U.S. patent application number 13/921779 was filed with the patent office on 2014-01-02 for inhalation device for drugs in powder form.
The applicant listed for this patent is ALMIRALL, S.A.. Invention is credited to Martin Herder, Gerhard Ludanek, Ingo Mett.
Application Number | 20140000602 13/921779 |
Document ID | / |
Family ID | 38290985 |
Filed Date | 2014-01-02 |
United States Patent
Application |
20140000602 |
Kind Code |
A1 |
Herder; Martin ; et
al. |
January 2, 2014 |
INHALATION DEVICE FOR DRUGS IN POWDER FORM
Abstract
To provide an inhalation device which has improved use
properties, particularly advanced moisture protection while in use,
an inhalation device (1) for powder drugs is proposed comprising at
least one storage chamber (13) for accommodating a plurality of
drug powder doses and a dosing device which includes at least one
dosing slider (15) which is movable approximately with a
translatory movement in a dosing slider passage (16) at least from
a filling position into an emptying position, wherein the
inhalation device (1) further includes a device for
inhalation-triggered automatic movement of the dosing slider (15)
from its filling position into the emptying position and a return
device for automatic movement of the dosing slider (15) back into
the filling position.
Inventors: |
Herder; Martin; (Rodgau,
DE) ; Ludanek; Gerhard; (Nidderau, DE) ; Mett;
Ingo; (Frankfurt, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ALMIRALL, S.A. |
Barcelona |
|
ES |
|
|
Family ID: |
38290985 |
Appl. No.: |
13/921779 |
Filed: |
June 19, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12520252 |
Aug 11, 2009 |
8567394 |
|
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PCT/EP2007/011372 |
Dec 21, 2007 |
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13921779 |
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Current U.S.
Class: |
128/203.15 |
Current CPC
Class: |
A61M 2202/064 20130101;
A61M 15/0096 20140204; A61M 15/0076 20140204; A61M 2205/583
20130101; A61M 15/007 20140204; A61M 15/0065 20130101; A61M 15/0081
20140204; A61M 15/008 20140204; A61M 15/0026 20140204; A61M
2205/8293 20130101; A61M 15/0091 20130101; A61M 15/0015
20140204 |
Class at
Publication: |
128/203.15 |
International
Class: |
A61M 15/00 20060101
A61M015/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 22, 2006 |
DE |
102006062196.4 |
Claims
1. An inhalation device for powder drugs comprising at least one
storage chamber for accommodating a plurality of drug powder doses
and a dosing device which includes at least one dosing slider which
is movable approximately with a translatory movement in a dosing
slider passage at least from a filling position into an emptying
position, wherein the inhalation device further includes a device
for inhalation-triggered automatic movement of the dosing slider
from its filling position into the emptying position and a return
device for automatic movement of the dosing slider back into the
filling position.
2. An inhalation device according to claim 1 wherein the dosing
slider passage with the at least one dosing slider and the storage
chamber is sealed off relative to the environment at least in the
filling position of the dosing slider.
3. An inhalation device (1) according to claim 1 wherein said at
least one storage chamber has at least one outlet opening through
which the powder drug can issue under the influence of the force of
gravity and the dosing slider has at least one dosing cavity,
wherein the dosing cavity in the filling position is under the
outlet opening and the dosing slider is movable out of its filling
position into the emptying position approximately transversely with
respect to the outflow direction of the drug powder from the outlet
opening of the at least one storage chamber.
4. An inhalation device according to claim 3 further comprising a
mouthpiece having an inhalation opening and an air passage which is
in flow communication with the mouthpiece and through which a
patient can suck an airflow for inhalation, wherein the dosing
cavity in the emptying position of the dosing slider is in the air
passage.
5. An inhalation device according to claim 4 wherein arranged in
the air passage is a trigger device for signalling when a
predetermined minimum airflow in the air passage is exceeded.
6. An inhalation device according to claim 5 further comprising a
valve device in the air passage in order to substantially close the
air passage, wherein the valve device is operatively connected to
the trigger device for inhalation-triggered opening of a
substantial part of the flow cross-section of the air passage when
a predetermined minimum airflow in the air passage is signalled as
being exceeded.
7. An inhalation device according to claim 6 wherein the valve
device is part of the device for inhalation-triggered automatic
movement of the dosing slider.
8. An inhalation device according to claim 5 wherein the trigger
device comprises a pivotably mounted, directly or indirectly
spring-loaded flap arranged in the air passage and the air passage
in the region of the flap is of a cross-sectional area which is
large in relation to the inhalation opening.
9. An inhalation device according to claim 8 wherein the flap is
pivotable about a pivot axis and the pivot axis extends through or
close to the centre of gravity of the flap.
10. An inhalation device according to claim 8 wherein the flap is
coupled to a thrust rod which is operatively connected to the
device for inhalation-triggered automatic movement of the dosing
slider in such a way that the device for inhalation-triggered
automatic movement of the dosing slider is held in a biased
position by the thrust rod when the flap is in its rest position
and the thrust rod releases the device for inhalation-triggered
automatic movement of the dosing slider when the flap is deflected
out of its rest position at least by a predetermined amount.
11. (canceled)
12. An inhalation device according to claim 8 wherein the flap is
pivotable about an axis and has a claw which is pivotable together
with the flap about the axis and which holds a spring-loaded
securing element and the contact face of which, with the securing
element, is formed by a sliding or rolling pairing, wherein the
securing element is operatively connected to the device for
inhalation-triggered automatic movement of the dosing slider in
such a way that the device for inhalation-triggered automatic
movement of the dosing slider is held in a biased position by the
securing element when the flap is in its rest position and the
securing element releases the device for inhalation-triggered
automatic movement of the dosing slider when the flap is deflected
out of its rest position by at least a predetermined amount.
13. An inhalation device according to claim 5 wherein the trigger
device has a piston connected to the air passage and the air
passage in the region of the piston has a cross-section which is
large in relation to the inhalation opening, wherein the piston is
coupled to a thrust rod which is operatively connected to the
device for inhalation-triggered automatic movement of the dosing
slider in such a way that the device for inhalation-triggered
automatic movement of the dosing slider is held in a biased
position by the thrust rod when the piston is in its rest position
and the thrust rod releases the device for inhalation-triggered
automatic movement of the dosing slider when the piston is
deflected out of its rest position by at least a predetermined
amount by a predetermined minimum airflow in the air passage, which
is initiated by a user of the inhalation device.
14. An inhalation device according to claim 1 wherein the device
for inhalation-triggered automatic movement of the dosing slider
out of its filling position into the emptying position has a drive
element which can be moved into a readiness position against the
force of a biasing spring and which has at least one sliding guide,
an entrainment portion or a cam portion which is operatively
connected to the dosing slider in its filling position and is
releasably arrested in its readiness position by a trigger device,
wherein the sliding guide, the entrainment portion or the cam
portion is so designed that the drive element upon a movement out
of the readiness position into a rest position moves the dosing
slider at least into the emptying position thereof by way of
entrainment portions.
15. An inhalation device according to claim 14 wherein the trigger
device has an engagement portion interacting with a stepped stop
element of the drive element, wherein the stepped stop element has
a first step and the drive element is arrested in an intermediate
position when the engagement portion of the trigger device
interacts with the first step, and a second step and the drive
element is held in its rest position when the engagement portion of
the trigger device interacts with the second step.
16. An inhalation device according to claim 15 wherein the dosing
slide is held in the emptying position by entrainment portions of
the drive element and the dosing slide, respectively, in the
intermediate position of the drive element.
17. An inhalation device according to claim 14, further comprising
a return device for automatic movement of the dosing slider back
into the filling position, the return device including a return
spring.
18. An inhalation device according to claim 17 wherein the dosing
slider is connected to the return spring and the sliding guide, the
entrainment portion or the cam portion is also so designed that in
the rest position of the drive element the dosing slider can return
into the filling position due to the force of the return
spring.
19. An inhalation device according to claim 17 wherein the drive
element in its rest position is out of engagement with the dosing
slider.
20. An inhalation device according to claim 14 wherein the drive
element is formed by a linearly movable sliding guide carrier.
21. An inhalation device according to claim 14 further comprising a
return device for automatically moving the dosing slider back into
the filling position, wherein the return device includes a further
sliding guide portion.
22. An inhalation device according to claim 14 wherein the sliding
guide or the cam portion is of a rectilinear configuration.
23. An inhalation device according to claim 14 wherein the sliding
guide or the cam portion is of a curved configuration, in
particular of an eccentrically curved configuration or of a helical
configuration.
24. An inhalation device according to claim 14 wherein the drive
element is formed by a drive rocker pivotable about a first pivot
axis.
25. An inhalation device according to claim 14 wherein the biasing
spring and/or the return spring is a spring selected from a group
of springs consisting of a coil spring, a spiral spring, a torsion
spring, an elastically deformable shaped body and a compressed air
storage means, wherein preferably the biasing spring has a
non-linear characteristic.
26. An inhalation device according to claim 14 further comprising a
rotary knob which is operatively connected to the drive element and
which has an operating handle, wherein the drive element can be
moved into its readiness position against the force of the biasing
spring by a user with the rotary knob.
27. An inhalation device according to claim 14 further comprising
an actuating button operatively connected to the drive element,
wherein the drive element can be moved into its readiness position
against the force of the biasing spring with the actuating button
by a user.
28. An inhalation device according to claim 4 further comprising a
closure cap for the mouthpiece, wherein the closure cap is
non-losably connected to the inhalation device and is movable from
a closure position in which the closure cap covers the mouthpiece
into an operative position in which the mouthpiece is accessible to
a patient.
29. An inhalation device according to claim 28 wherein the device
for inhalation-triggered automatic movement of the dosing slider
out of its filling position into the emptying position has a drive
element which can be moved into a readiness position against the
force of a biasing spring and which has at least one sliding guide,
an entrainment portion or a cam portion which is operatively
connected to the dosing slider in its filling position and is
releasable arrested in its readiness position by a trigger device,
wherein the sliding guide, the entrainment portion or the cam
portion is so designed that the drive element upon a movement out
of the readiness position into a rest position moves the dosing
slider at least into the emptying position thereof by way of
entrainment portions; wherein the drive element is formed by a
linearly movable sliding guide carrier; and wherein the closure cap
or the sliding guide carrier has one or more entrainment portions
and the closure cap is movable out of the closure position and is
pivotable into the operative position, wherein the closure cap or
the sliding guide carrier has a sliding guide complementary to the
entrainment portion or portions in such a way that the sliding
guide carrier is movable by the movement of the closure cap out of
the closure position into the operative position against the force
of the biasing spring from its rest position into its readiness
position.
30. An inhalation device according to claim 29 wherein the
complementary sliding guide has a track for the entrainment portion
or portions so that the closure cap is also movable in the
readiness position of the sliding guide into the closure
position.
31. An inhalation device according to claim 30 wherein the track is
such that the sliding guide carrier is fixed in its readiness
position by entrainment portions of the closure cap independently
of the trigger device when the closure cap is in its closure
position.
32. An inhalation device according to claim 29 wherein the
complementary sliding guide is inclined with respect to the guide
at an angle .alpha. of between 15.degree. and 45.degree..
33. An inhalation device according to claim 29 wherein the
complementary sliding guide extends non-rectilinearly.
34. An inhalation device according to claim 29 wherein the closure
cap has at least one entrainment portion and the closure cap is
movable out of the closure position along a guide substantially
rectilinearly into an intermediate position and is pivotable out of
the intermediate position into the operative position, wherein the
inhalation device further has an eccentric disc operatively
connected to the sliding guide carrier so that the eccentric disc
is rotated by the entrainment portion of the closure cap upon the
rectilinear movement thereof about a fixing axis in such a way that
the sliding guide carrier is movable from its rest position into
its readiness position by the movement of the closure cap out of
the closure position into the intermediate position by way of the
eccentric disc against the force of the biasing spring.
35. An inhalation device according to claim 29 wherein the closure
cap has a pressure lever and the closure cap is pivotable out of
the closure position into the operative position, wherein the
pressure lever of the closure cap is pivotable about an axis in
such a way that the sliding guide carrier is movable from its rest
position into its readiness position by the movement of the closure
cap out of the closure position into the operative position by way
of the pressure lever against the force of the biasing spring.
36. An inhalation device according to claim 24 wherein further
comprising a closure cap for the mouthpiece, wherein the closure
cap is non-closably connected to the inhalation device and is
movable from a closure position in which the closure cap covers the
mouthpiece into an operative position in which the mouthpiece is
accessible to a patient; and wherein the closure cap has at least
one entrainment portion and a transmission rocker which is
operatively connected to the driver rocker and which is pivotable
about a second pivot axis and the closure cap is pivotable out of
the closure position into the operative position about a third
axis, wherein the at least one entrainment portion of the closure
cap co-operates with at least one operative end of the transmission
rocker in such a way that the drive rocker is movable out of its
rest position into its readiness position by the movement of the
closure cap about the third axis out of the closure position into
the operative position by way of the transmission rocker against
the force of the biasing spring.
37. An inhalation device according to claim 36 wherein the drive
rocker and the transmission rocker are in mutual engagement in such
a way that their rotation takes place in opposite relationship
about the first and second pivot axes.
38. An inhalation device according to claim 37 wherein the moment
of inertia of the drive rocker about the first pivot axis and the
moment of inertia of the transmission rocker about the second pivot
axis are approximately equal.
39. An inhalation device according to claim 36 wherein the at least
one operative end of the transmission rocker is of such a
configuration that the operative end is connected in positively
locking relationship by the at least one entrainment portion of the
closure cap upon movement of the closure cap out of the closure
position into the operative position about the third axis and
transmits the moment applied by the at least one entrainment
portion to the transmission rocker and elastically evades the
entrainment portion upon movement of the closure cap out of the
operative position into the closure position.
40. An inhalation device according to claim 36 wherein the
transmission rocker has two rocker elements which are arranged on
both longitudinal sides of the inhalation device pivotably about
the second pivot axis and are connected together with at least one
yoke, wherein the thrust rod holds the transmission rocker in the
biased position of the drive rocker by engagement with the yoke
when the flap is in its rest position and the thrust rod enables
the travel movement of the yoke when the flap is deflected out of
its rest position at least by a predetermined amount so that the
transmission rocker and the drive rocker are movable by the biasing
spring out of their readiness position into their rest
position.
41. An inhalation device according to claim 15 wherein there is
further provided a counting device for detecting the number of
delivered drug doses, wherein the counting device individually
detects each dosing operation and is connected to a locking device
which blocks the closure cap upon the attainment of a predetermined
number of delivered doses so that the closure cap is no longer
movable into the closure position.
42. An inhalation device according to claim 41 wherein the counting
device is connected to the engagement portion of the trigger device
and that the stepped stop element of the drive element has an
opening or recess, and the drive element is urged by the biasing
spring to a blocking position, when the engagement portion engages
with the opening or recess.
43. An inhalation device according to claim 42 wherein the drive
element in its blocking position engages blockingly into the path
of the closure cap so that the closure cap can no longer be moved
into the closure position.
44. An inhalation device according to claim 41 wherein the counting
device includes a dose-accurate display.
45. An inhalation device according to claim 41 wherein the locking
device has a spring-loaded locking element which engages into a
groove which is opened at a predetermined number of doses and in
that case blockingly engages into a sliding guide of the mechanism
of the closure cap so that the closure cap can no longer be moved
into the closure position.
46. An inhalation device according to claim 45 wherein the locking
element of the locking device is coupled to a signal plate which is
displayed upon blocking engagement of the locking device.
47. An inhalation device according to claim 41 wherein the locking
device has a spring-loaded blocking rod which is movable from a
rest position into a blocking position upon the attainment of a
predetermined number of delivered doses and in its blocking
position engages blockingly into the path of the closure cap so
that the closure cap can no longer be moved into the closure
position.
48. An inhalation device according to claim 1 wherein the at least
one storage chamber has at least one outlet opening through which
the powder drug can issue under the influence of the force of
gravity, and a filling opening which is disposed substantially in
opposite relationship to the outlet opening, wherein the filling
opening is sealingly closed.
49. An inhalation device according to claim 48 wherein the filling
opening is closed with an aluminium blister film and sealed with a
LDPE layer.
50. An inhalation device according to claim 1 wherein the dosing
slider passage has at its one end towards the environment an
opening through which a part of the dosing slider can pass and a
contact surface for a seal is provided around the opening, wherein
the dosing slider has a sealing surface which is provided in a
plane approximately in transverse relationship with its direction
of movement out of the filling position into the emptying
position.
51. An inhalation device according to claim 50 wherein an elastic
seal is provided on the dosing slider and/or the contact surface,
wherein the elastic seal is formed by injection on the dosing
slider passage and/or the dosing slider.
52. An inhalation device according to claim 51 wherein the elastic
seal can be formed by a sealing rib on the dosing slider passage
and/or the dosing slider, which is sealingly deformable by a
biasing force which holds the dosing slider in the dosing slider
passage.
53. An inhalation device according to claim 1 wherein the
inhalation device further has a display for signalling inhalation
readiness and/or successful delivery of the medicament.
54. An inhalation device according to claim 4 further comprising a
breaking-down device for breaking down agglomerates and the like in
the drug powder in flow communication with the mouthpiece, wherein
the mouthpiece and the breaking-down device are removable for
cleaning by the user and the mouthpiece and the breaking-down
device are so adapted that they can only be removed or fitted
together or are of a one-piece nature.
55. An inhalation device according to claim 1 wherein the at least
one storage chamber is provided by a cartridge holder device and a
lid, wherein the lid has a shape capable of receiving the drug
powder content of the storage chamber in an upside-down position of
the inhalation device.
56. An inhalation device according to claim 55 wherein the lid is
sealingly fixed onto the cartridge holder by snap connectors.
57. An inhalation device according to claim 55 wherein the
cartridge holder device comprises two storage chambers each covered
by a lid, wherein the cartridge holder device comprises a twin
dosing slider.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Divisional of U.S. patent application
entitled INHALATION DEVICE FOR DRUGS IN POWDER FORM, Ser. No.
12/520,252 filed Aug. 11, 2009, which is a U.S. National Stage
application based on International Application No.
PCT/EP2007/011372 filed Dec. 21, 2007 entitled INHALATION DEVICE
FOR DRUGS IN POWDER FORM, which is based on German Application No.
102006062196.4 filed Dec. 22, 2006, the entire content of which is
expressly incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention concerns an inhalation device for drugs in
powder form comprising at least one storage chamber for
accommodating a plurality of drug powder doses and a dosing device
which includes at least one dosing slider which is movable
approximately with a translatory movement in a dosing slider
passage at least from a filling position into an emptying
position.
[0004] 2. Description of the Related Art
[0005] In the field of treating bronchial diseases but also other
diseases in which medication can be effected by way of the
respiratory tract, it is known to apply medicaments in powder form,
besides the atomisation of solutions or suspensions to afford
inhalable aerosols, Many different examples of such medicaments are
described in the literature, purely by way of example we refer to
WO 93/11773, EP 0 416 950 A1 and EP 0 416 951 A1. A usual form of
application in that respect is a supply by way of an inhalation
device or inhaler.
[0006] In the case of inhalers for powder drugs, such inhalers are
known both for the application of an individual dose, and also
inhalation devices which have a store for a multiplicity of drug
doses. In regard to the latter it is known either to provide
separate storage chambers for a respective individual dose or an
individual receiving chamber for accommodating a plurality of doses
of a medicament.
[0007] In the case of inhalers which have a plurality of individual
doses in separate storage chambers, those are known in which
individual chambers of the inhaler are respectively filled with a
drug dose. An example of such an inhaler is described in U.S. Pat.
No. 5,301,666 A. It is however also known for a plurality of drug
powder doses to be respectively separately disposed in the spaces
or chambers of so-called blister packs. An example of such a
blister pack for use with an inhaler is described in DE 44 00 083
C2. Such a blister pack which at the same time is in the form of a
disposable inhaler is described for example in DE 44 00 084 A1.
[0008] An inhalation device into which blister packs can be fitted
which include respective separate storage chambers for individual
doses of a powder drug and which can be emptied successively by
means of the inhalation device is described for example in DE 195
23 516 C1.
[0009] Many different examples of inhalers with a storage chamber
for a plurality of drug doses are described in the state of the
art. An example with a replaceable storage container is described
in German patent specification 846 770, and another one is
described in WO 95/31237.
[0010] A serious problem in inhalation systems in which a plurality
of doses of a medically effective substance is disposed in a common
storage chamber is apportioning an individual close for an
individual inhalation operation. A large number of proposed
solutions have been set forth in that respect as described for
example in U.S. Pat. No. 2,587,215 A and U.S. Pat. No. 4,274,403 A.
Other forms of arrangements for dosing an individual drug powder
dose from a storage chamber for a plurality of drug doses are also
described in WO 92/09322, WO 93/16748, WO 93/03785, U.S. Pat. No.
6,029,661 A and DE 35 35 561 C2 as well as GB 2 165 159 A. An
interchangeable cartridge for accommodating a plurality of doses of
a drug powder with an integrated dosing slider is known from DE 195
22 415 A1.
[0011] A further serious problem in the inhalation of drug powder
is the breakdown of the galenic powder formulations into particles
which can reach the lungs. The active substances administered in
that way are generally brought together with carrier substances in
order to achieve reasonable dosability of the medically active
substance and in order to set further properties of the drug powder
which for example can involve storage capability.
[0012] Approaches involving the design configurations of powder
inhalers which are intended to provide for the provision of
particles which are capable of reaching the lungs in an air flow
are described for example in EP 0 640 354 A2, U.S. Pat. No.
5,505,196 A, U.S. Pat. No. 5,320,714 A, U.S. Pat. No. 5,435,301 A,
U.S. Pat. No. 301,666 A, DE 195 22 416 A1 and WO 97/00703. In that
respect proposals are also known for using auxiliary energy for
producing the airflow, for example from ZA-A 916741.
[0013] It is quite generally also known in regard to the use of
medicaments for inhalation in powder form for active substances to
be combined by the application of prefabricated active substance
mixtures. Corresponding proposals are to be found in EP 0 416 951
A1 and WO 93/11773, for example for the combination of salmeterol
with fluticasone or formoterol with budesonide.
[0014] WO 00/74754 and many other publications over more than
twenty years describe that a serious problem arises in regard to
moisture, particularly with powder inhalers. In that respect
moisture can not only have a disadvantageous effect on the
pharmaceutically active medicament composition but in particular
can adversely affect the interplay of physical and chemical
parameters of the combination of active substance and adjuvant
substances. As a result for example lumps can occur or breakdown of
the inhaled powder into particles capable of reaching the lungs can
be impeded. All those circumstances can lead to problems in regard
to dosability and the effectiveness of administration of a
medicament powder.
[0015] To alleviate those disadvantages various attempts have
already been made in the past to reduce the penetration of moisture
into a powder inhaler by the use of seals. In addition attempts
were made to reduce the detrimental effects of moisture which has
penetrated into the inhaler, by the provision of drying agents in
order to absorb the moisture and in particular to keep down the
level of air humidity in the storage chambers. Sealed dosing
cavities in a multi-dose powder inhaler as well as a multi-digit
counting mechanism are known from WO 92/00771. It will be noted
however that dosing is only described by way of a rotary movement
of a frustoconical dosing member.
[0016] Measures for moisture protection of medicament in powder
form for inhalation in respect of dosing by means of a dosing
slider are described for example in DE 102 02 940 A1, US 2003
0136405 A and WO 03/061742 A2.
[0017] Particularly with conventional aerosol inhalers, it was in
many cases considered that actuation for dose delivery from the
aerosol container and the fact of sucking in an airflow by the
patient using it has to be co-ordinated, was a disadvantage. That
considerably reduces the reliability of application of the
medicament into the lung. Many different solutions have therefore
been proposed in order to decouple actuation by the patient from
the inhalation process and thus application of the dose. The
difficulty in synchronizing the inhalation with the manual
operation of the distributor part of an inhaler is for instance
discussed in U.S. Pat. No. 5,239,992 A.
[0018] Numerous inventors have therefore already concerned
themselves with the problem of inhalation-triggered dose delivery
in the case of inhalers, for decades. For example DE 39 01 963 C1
discloses automatic actuation of a valve of an aerosol container.
In that respect the invention described in that document includes
sensor devices as well as an electronic control and various
proposals for an actuating mechanism driven by electric motor
means. In the Figures the patent specification includes a whole
series of proposals for possible design configurations of the
actuating mechanism which are all based on a rotary drive movement
by means of an electric motor and provide for conversion into very
small travel movements which are required for the actuation of a
valve of an aerosol container which is under pressure.
[0019] However, from U.S. Pat. No. 5,113,855 A a proposal is known
to at all separate the dosing and aerolization of medicament powder
totally from the inhalation step to avoid the need for any
triggering.
[0020] An inhalation-triggered opening and closing movement of a
closure of a dosing passage is known from WO 99/47199 and WO
99/06092. In accordance with the disclosures in those documents, a
spring-loaded closure of a dosing passage is moved by way of a
valve flap which is disposed in a main air passage and which is
actuated by the inhalation flow of the patient. The closure is
pulled away upon corresponding deflection of the valve flap from
the opening of the dosing passage and returns due to spring force
into its starting position when the valve flap is no longer held
open by the airflow. It will be appreciated however that this
arrangement also does not have any seal as that dosing flap is only
intended to close a dosing passage and is not in communication with
a storage container for powder drugs. The actual dose delivery
operation is effected by opening an individual dose blister in
well-known form. Evidently the aim is only to ensure that no
medicament powder passes into the air passage extending straight
from the front rearwardly through the device, and probably trickles
out when the inhaler is in an inclined position.
[0021] FR 2 709 653 A discloses a dosing device which is spring
loaded from depressing a knob by the user, and the dosing device is
released by a flap to move to a discharge position when a patient
exerts suction in the inhalation duct.
[0022] Inhalation-triggered delivery of a dose from an aerosol
container under pressure is known for example by prior use by
Fujisawa Deutschland GmbH. In the case of the aerosol inhaler which
is marketed by that corporation under the mark Junik.RTM.
Autohaler.RTM. the aerosol container is biased by the user prior to
the inhalation operation, insofar as a lever is used to compress a
compression coil spring which presses against the container. The
aerosol container is held by a movable frame connected to an air
flap. When the air flap is deflected by the inhalation suction of
the patient or otherwise mechanically, the frame is pivoted away to
such an extent that the aerosol container can move with respect to
the dosing valve which is held in a firm seat, to such an extent
that the dosing valve opens to deliver a dose. In that respect the
biasing of the spring is sufficient to overcome the closing force
of the dosing valve. The aerosol container remains in the last
position until the lever is pivoted back into its starting position
again by the user. What is very troublesome for the user is the
relatively hard and loud triggering impact upon activation of the
dosing operation due to the quite high spring biasing and the
comparatively large mass of the aerosol container, which is moved
in the triggering operation.
[0023] Another inhalation-triggered opening of an aerosol container
for dosing purposes by means of a spring which is activated by the
actuation of a protective cap is known from WO 93/24167 (Norton
Health Care Ltd., GB). The aerosol container is held in a readiness
position by an evacuated and sealed intermediate chamber against
the force of the spring. The dosing operation is effected by way of
an airflow-actuated valve which permits venting of the intermediate
chamber and thus release of the spring and a downward movement of
the aerosol container. As the dosing valve of the aerosol container
is held fast the movement of the container leads to an opening
movement of the valve and thus delivery of an aerosol dose. That
patent application at the same time also describes dose counting
with an index ring which is advanced by way of a stepping mechanism
with each dosing stroke movement. When a predetermined number of
doses have been taken the ring disappears from the viewing window
and can show an "empty" marking Biasing of the spring is effected
by way of a pivotal movement of a cap which actuates a receiving
holding means for the aerosol container by way of a cam disc and a
linkage, and in so doing compresses the spring.
[0024] The connection of a display formed by a ring which is moved
progressively behind a viewing window, with an interchangeable
powder cartridge, with a device for blocking the inhaler, is known
from EP 1 616 592 A1. The blocking device is controlled by way of a
groove in the ring and engages into the actuating mechanism for
powder dosing. Similarly to the above-described document, the
display however does not afford any possible way of dose-accurately
reading off the doses which are still present in the storage
container. Intervention of the blocking device can also not be
predicted in accurate dosing relationship.
[0025] An MDPI in which the dosing element is actuated by way of a
protective cap, with a refillable storage container having a plug
which can serve as a container for a drying agent, and a dose
counting mechanism, are known in principle from WO 93/03782.
[0026] EP 0 865 302 B1 discloses an inhaler in which a filled
dosing cavity passes into a closure means upon further opening of a
protective cap, and is closed by the closure means. A valve plate
is releasable from its rest position in order to advance the
closure means, in which case the advance movement of the closure
means is permitted, against adjustable arresting means, only upon
the application of a defined minimum intensity of inhalation by a
patient, and the dosing cavity is opened only with the advance
movement of the closure means so that the dose of medicament powder
can be inhaled. That arrangement is highly special and complicated
and expensive but does not prevent the loss of a dose which has not
yet been inhaled, without affording particular protection from
moisture, Upon actuation by a patient without inhalation occurring,
the apportioned drug dose can remain for any period of time outside
the storage means and in that case is exposed to atmospheric
influences.
[0027] DE 198 25 434 C2 and EP 1 051 212 B1 disclose inhalers which
each have a rotating dosing drum and a biasing mechanism which both
activates a spring and also compresses an air volume, the mechanism
being actuated by pivotal movement of a non-removable protective
cap. Also described is a variant in which the biasing force for the
metering operation is only produced by way of a rotary leg spring.
The leg spring, triggered by the inhalation flow, drives the dosing
drum of the inhaler from a filling position into an emptying
position.
[0028] It is known from WO 95/31237 A1 to provide a spring on a
dosing slider of an inhaler. The dosing slider can be pressed
directly by hand by the user from a filling position into an
emptying position against the force of a spring so that, after the
dosing slider is released, it is pushed back by the spring into the
filling position again.
[0029] None of the known documents however describes an arrangement
which would make it possible for the drug supply including the dose
pending for delivery to be protected from moisture and other
detrimental influences independently of the operating behaviour of
the patient as the user.
SUMMARY OF THE INVENTION
[0030] Therefore the problem of the invention is to provide an
inhalation device which has improved use properties.
[0031] In accordance with the invention that problem is solved by
an inhalation device for powder drugs comprising at least one
storage chamber for accommodating a plurality of drug powder doses
and a dosing device which includes at least one dosing slider which
is movable approximately with a translatory movement in a dosing
slider passage at least from a filling position into an emptying
position, wherein the inhalation device further includes a device
for inhalation-triggered automatic movement of the dosing slider
from its filling position into the emptying position and a return
device for automatic movement of the dosing slider back into the
filling position.
[0032] Unlike the situation with previously known inhalers, the
invention makes it possible for the first time for a dose of a
powder medicament to be kept within the particularly
moisture-protected region of the storage chamber, independently of
any operating actions on the part of a patient, until actual
inhalation. It is thus possible for the drug powder dose to be
protected from ambient moisture for as long as possible and to
avoid corresponding disadvantageous effects. In addition the
automatic return of the dosing slider into its filling position
immediately after dose delivery ensures that the hermetic moisture
protection for the storage chamber is interrupted only for the
shortest possible period, namely the moment of dispensing the
apportioned drug dose. That provides that the remaining stored
supply of drug is particularly effectively protected from
moisture.
[0033] The inhaler according to the invention for the first time
offers for a medicament stored supply with a plurality of drug
powder doses, practically the same protection from ambient
influences, as was hitherto only possible in individual dose
blisters. In comparison with known inhalers for blister packs
however it was possible to achieve a greater degree of economy, as
well as better dose dispensing and thus better reproducibility of
the medication. In addition the configuration of an inhalation
device according to the invention affords the further advantage
that overdosing of drug by multiple activation of the inhaler
without effective inhalation is not possible. Finally, it cannot
happen with the inhalation device according to the invention that,
by virtue of actuation by the patient, a drug dose is presented
which, upon careless or awkward handling with the inhalation
device, could trickle out of the device prior to actual inhalation
or could collect at unsuitable locations in the device. That
therefore also affords particular protection against unintended
under-dosing of the medicament upon inhalation by the user.
[0034] Preferably an inhalation device according to the invention
is characterised in that the dosing slider passage with the at
least one dosing slider and the storage chamber is sealed off
relative to the environment at least in the filling position of the
dosing slider.
[0035] In a particularly desirable embodiment of the invention the
at least one storage chamber has at least one outlet opening
through which the powder drug can issue under the influence of the
force of gravity and the dosing slider has at least one dosing
cavity, wherein the dosing cavity in the filling position is under
the outlet opening and the dosing slider is movable out of its
filling position into the emptying position approximately
transversely with respect to the outflow direction of the drug
powder from the outlet opening of the at least one storage
chamber.
[0036] In order to provide for breath-triggered dosing and
application of the drug powder, which is independent of the actual
mechanical biasing of the inhaler by the patient, the inhaler
preferably further includes a mouthpiece having an inhalation
opening and an air passage which is in flow communication with the
mouthpiece and through which a patient can suck an airflow for
inhalation, wherein the dosing cavity in the emptying position of
the dosing slider is in the air passage.
[0037] Desirably arranged in the air passage is a trigger device
for signalling when a predetermined minimum airflow in the air
passage is exceeded. Thus dosing of the drug powder can be
triggered when a predetermined minimum airflow is exceeded.
[0038] In a particularly advantageous feature the inhalation device
has a valve device in the air passage in order to substantially
close the air passage, wherein the valve device is operatively
connected to the trigger device for inhalation-triggered opening of
a substantial part of the flow cross-section of the air passage
when a predetermined minimum airflow in the air passage is
signalled as being exceeded, in particular the valve device is part
of the device for inhalation-triggered automatic movement of the
dosing slider. By virtue of that arrangement, upon an inhalation by
the patient, firstly a suction airflow is built up in the suction
passage, which is already ready upon inhalation-triggered opening
of the dosing passage cross-section and thus ensures complete
emptying of the one dosing cavity of the dosing slider.
[0039] In a preferred embodiment the trigger or valve device
comprises a pivotably mounted, directly or indirectly spring-loaded
flap arranged in the air passage, wherein the air passage in the
region of the flap is of a cross-sectional area which is large in
relation to the inhalation opening, in order to ensure reliable
reproducible triggering even if a weakened patient can only inhale
at a low flow rate.
[0040] Particularly advantageously the flap is pivotable about a
pivot axis and the pivot axis extends through or close to the
centre of gravity of the flap. That provides that the flap is
balanced about the pivot axis and thus in the event of an impact
against the device, for example if the device is dropped, no
moments induced by the mass of the flap occur about the pivot axis,
thus preventing improper triggering of the device for
inhalation-triggered automatic movement of the dosing slider.
[0041] In another advantageous embodiment of the invention the flap
is coupled to a thrust rod which is operatively connected to the
device for inhalation-triggered automatic movement of the dosing
slider in such a way that the device for inhalation-triggered
automatic movement of the dosing slider is held in a biased
position by the thrust rod when the flap is in its rest position
and the thrust rod releases the device for inhalation-triggered
automatic movement of the dosing slider when the flap is deflected
out of its rest position at least by a predetermined amount.
[0042] The coupling between the flap and the thrust rod can be
formed for example by way of a toothed ring segment on the flap and
a portion on the thrust rod, which is in the form of a rack. The
term thrust rod may be understood in the context of the present
application to also include other forms than a rod, e.g. the shape
of a bent fork.
[0043] It can also be advantageous if the flap is pivotable about
an axis and has a claw which is pivotable together with the flap
about the axis and which holds a spring-loaded securing element and
the contact face of which, with the securing element, is formed by
a sliding or rolling pairing, wherein the securing element is
operatively connected to the device for inhalation-triggered
automatic movement of the dosing slider in such a way that the
device for inhalation-triggered automatic movement of the dosing
slider is held in a biased position by the securing element when
the flap is in its rest position and the securing element releases
the device for inhalation-triggered automatic movement of the
dosing slider when the flap is deflected out of its rest position
by at least a predetermined amount.
[0044] In another embodiment which is of an advantageously short
structure the trigger device has a piston connected to the air
passage and the air passage in the region of the piston has a
cross-section which is large in relation to the inhalation opening,
wherein the piston is coupled to a thrust rod which is operatively
connected to the device for inhalation-triggered automatic movement
of the dosing slider in such a way that the device for
inhalation-triggered automatic movement of the dosing slider is
held in a biased position by the thrust rod when the piston is in
its rest position and the thrust rod releases the device for
inhalation-triggered automatic movement of the dosing slider when
the piston is deflected out of its rest position by at least a
predetermined amount by a predetermined minimum airflow in the air
passage, which is initiated by a user of the inhalation device.
[0045] In a particularly preferred embodiment of the invention the
inhalation device according to the invention is characterised in
that the device for inhalation-triggered automatic movement of the
dosing slider out of its filling position into the emptying
position has a drive element which can be moved into a readiness
position against the force of a biasing spring and which has at
least one sliding guide, an entrainment portion or a cam portion
which is operatively connected to the dosing slider in its filling
position and is releasably arrested in its readiness position by a
trigger device, wherein the sliding guide, the entrainment portion
or the cam portion is so designed that the drive element upon a
movement out of the readiness position into a rest position moves
the dosing slider at least into the emptying position thereof by
way of one or more entrainment portions.
[0046] In a particularly preferred embodiment of the invention the
inhalation device according to the invention is characterised in
that the trigger device has an engagement portion interacting with
a stepped stop element of the drive element, wherein the stepped
stop element has a first step and the drive element is arrested in
an intermediate position when the engagement portion of the trigger
device interacts with the first step, and a second step and the
drive element is held in its rest position when the engagement
portion of the trigger device interacts with the second step,
preferably, if the dosing slide is held in the emptying position by
entrainment portions of the drive element and the dosing slide,
respectively, in the intermediate position of the drive element.
Such embodiment is particularly favourable in providing exact
dosing of powdered medicaments to a patient as this embodiment does
not only allow to deliver the drug powder from the storage chamber
once the patient has established an inspiration flow sufficient to
activate the trigger design, thus preventing the drug powder from
being exposed to the atmosphere longer than needed, but also to
present the drug powder to the inhalation air flow as long as the
inspiration flow exceeds a predetermined threshold. Because of that
removal of the full dose of drug powder presented is ensured during
inhalation, thus providing best possible lung deposition at very
little variations, so that the administration of medicaments via
inhalation will also be possible for applications where exact
reproduction of the prescribed dose is required.
[0047] Preferably the inhalation device further includes a return
device for automatic movement of the dosing slider back into the
filling position, the return device including a return spring. In
that respect the return of the dosing slider into its filling
position is not dependent on the inertia of the drive element and
not substantially on the position of the inhalation device. The
dosing slider is preferably connected by means of a return spring
and is moved thereby back into the filling position, wherein the
sliding guide, the entrainment portion or the cam portion is also
so designed that in the rest position of the drive element the
dosing slider can return into the filling position due to the force
of the return spring. That ensures secure reliable sealing
integrity for the stored drug supply, which is independent of
component tolerances.
[0048] That sealing integrity is particularly reliably maintained
if the drive element in its rest position is out of engagement with
the dosing slider.
[0049] In an advantageous embodiment of the invention the
inhalation device is characterised in that the drive element is
formed by a linearly movable sliding guide carrier.
[0050] The return device for automatically moving the dosing slider
back into the filling position can include a further sliding guide
portion. Such an arrangement affords a positive guidance effect, as
in the case of the forward movement. With such an arrangement, it
is possible to prevent temporary opening of the seal at the dosing
slider if for example the device falls to the ground.
[0051] It is particularly simple if the sliding guide or the cam
portion is of a rectilinear configuration. Adaptation of the
transmission between for example a drive spring and the dosing
slider in dependence on the actuating travel can be obtained if the
sliding guide or the cam portion is of a curved configuration, in
particular of an eccentrically curved configuration.
[0052] Preferably a resilient element is used for storage of the
energy necessary for the dosing movement.
[0053] A particularly compact arrangement with a torsion or rotary
leg spring can be achieved if the sliding guide or the cam portion
is of a helical configuration.
[0054] In a particularly preferred embodiment of the invention the
drive element is formed by a drive rocker pivotable about a first
pivot axis. That arrangement makes it possible to achieve a
particularly reliable mode of operation substantially independently
of manufacturing tolerances and there is a reduced risk of
operational disturbances, for example after the inhalation device
has been dropped.
[0055] Particularly in terms of simple and inexpensive assembly of
an inhalation device according to the invention it is advantageous
if the biasing spring and/or the return spring is a spring selected
from a group of springs consisting of a coil spring, a spiral
spring, a torsion spring, an elastically deformable shaped body and
a compressed air storage means.
[0056] A particularly desirable adaptation in respect of the
kinematics of the sliding guide carrier can be achieved if the
biasing spring has a non-linear characteristic.
[0057] An inhalation device according to the invention is protected
particularly well from inadvertent actuation if there is provided a
rotary knob which is operatively connected to the sliding guide
carrier and which has an operating handle, wherein the sliding
guide carrier can be moved into its readiness position against the
force of the biasing spring by a user with the rotary knob.
Rotational actuating movements do not occur randomly and
unintentionally under usual conditions, for example when putting a
hand into a jacket pocket in which an inhalation device according
to the invention is to be found, so that unintentional biasing of
the device is avoided.
[0058] An inhalation device according to the invention can be
reliably operated for patients suffering from degenerative diseases
on the hands such as for example severe rheumatism, gout or
arthrosis, if there is provided an actuating button operatively
connected to the sliding guide carrier, wherein the sliding guide
carrier can be moved into its readiness position against the force
of the biasing spring with the actuating button by a user.
[0059] An embodiment of an inhalation device according to the
invention, which is particularly preferred and operationally
reliable and safe in respect of incorrect operation is
characterised by a closure or protective cap for the mouthpiece,
wherein the closure cap is non-losably connected to the inhalation
device and is movable from a closure position in which the closure
cap covers the mouthpiece into an operative position in which the
mouthpiece is accessible to a patient. In that way it is impossible
to use the inhalation device without previously activating it.
[0060] Activation of the biasing device for the sliding guide
carrier by opening or closing the closure cap can be implemented if
the closure cap or the sliding guide carrier has one or more
entrainment portions and the closure cap is movable out of the
closure position into the operative position substantially
rectilinearly, or rotationally, or with a combined movement.
[0061] In an embodiment the closure cap or the sliding guide
carrier has a sliding guide complementary to the entrainment
portion or portions in such a way that the sliding guide carrier is
movable by the movement of the closure cap out of the closure
position into the operating position against the force of the
biasing spring from its rest position into its readiness
position.
[0062] An inhalation device according to the invention is
particularly suitable in practical use if the complementary sliding
guide has a track for the entrainment portion or portions so that
the closure cap is also movable in the readiness position of the
sliding guide into the closure position. That ensures untroubled
functioning even if for any reasons the device is closed again
without successful inhalation and the closure cap is later opened
again.
[0063] A particularly high level of safeguard against malfunctions,
particularly upon being dropped, for an inhalation device according
to the invention is achieved if the track is such that the sliding
guide carrier is fixed in its readiness position by entrainment
portions of the closure cap independently of the trigger device
when the closure cap is in its closure position.
[0064] In that respect it is particularly desirable if the
complementary sliding guide is inclined with respect to the guide
at an angle a at which no self-locking can occur, in particular
between 15.degree. and 45.degree., in particular if the
complementary sliding guide extends non-rectilinearly.
[0065] For making use of a pivotal movement for biasing the biasing
spring for the sliding guide carrier it is advantageous if the
closure cap has at least one entrainment portion and the closure
cap is movable out of the closure position along a guide
substantially rectilinearly into an intermediate position and is
pivotable out of the intermediate position into the operative
position, wherein the inhalation device further has an eccentric
disc operatively connected to the sliding guide carrier so that the
eccentric disc is rotated by the entrainment portion of the closure
cap upon the rectilinear movement thereof about a fixing axis in
such a way that the sliding guide carrier is movable from its rest
position into its readiness position by the movement of the closure
cap out of the closure position into the intermediate position by
way of the eccentric disc against the force of the biasing
spring.
[0066] Alternatively it may also be advantageous if the closure cap
has a pressure lever and the closure cap is pivotable out of the
closure position into the operative position, wherein the pressure
lever of the closure cap is pivotable about an axis in such a way
that the sliding guide carrier is movable from its rest position
into its readiness position by the movement of the closure cap out
of the closure position into the operative position by way of the
pressure lever against the force of the biasing spring.
[0067] In an embodiment which is particularly simple to operate for
the user the biasing of the dosing mechanism is achieved by a
purely rotational mover-rent of the protective cap.
[0068] In another particularly preferred and advantageous
embodiment of the invention the closure cap has at least one
entrainment portion and a transmission rocker which is operatively
connected to the driver rocker and which is pivotable about a
second pivot axis and the closure cap is pivotable out of the
closure position into the operative position about a third axis,
wherein the at least one entrainment portion of the closure cap
co-operates with at least one operative end of the transmission
rocker in such a way that the drive rocker is movable out of its
rest position into its readiness position by the movement of the
closure cap about the third axis out of the closure position into
the operative position by way of the transmission rocker against
the force of the biasing spring.
[0069] That enables even patients who are under severe stress
reliable and secure inhalation without particular handling
operations having to be implemented. As a result an inhalation
device according to the invention is also particularly suitable for
patients suffering from severe acute asthma attacks or patients who
must still reliably inhale a medicament under exceptional
psychological and physical conditions.
[0070] It is particularly desirable if the drive rocker and the
transmission rocker are in mutual engagement in such a way that
their rotation takes place in opposite relationship about the first
and second pivot axes. That arrangement provides that the moments
involved upon triggering drug delivery substantially cancel each
other out so that the patient is only slightly adversely affected
by return forces which are perceived as a knock and corresponding
noise. As a result acceptance of a medication with an inhalation
device is markedly improved. That is the case in particular if the
moment of inertia of the drive rocker about the first pivot axis
and the moment of inertia of the transmission rocker about the
second pivot axis are approximately equal.
[0071] In a particularly advantageous configuration the inhalation
device according to the invention is characterised in that the at
least one operative end of the transmission rocker is of such a
configuration that the operative end is connected in positively
locking relationship by the at least one entrainment portion of the
closure cap upon movement of the closure cap out of the closure
position into the operative position about the third axis and
transmits the moment applied by the at least one entrainment
portion to the transmission rocker and elastically evades the
entrainment portion upon movement of the closure cap out of the
operative position into the closure position. By virtue thereof it
is possible for the closure cap to be moved over the mouthpiece
again in a protective position even if a drug dose has not been
taken.
[0072] In a particularly operationally reliable configuration the
inhalation device according to the invention is characterised in
that the transmission rocker has two rocker elements which are
arranged on both longitudinal sides of the inhalation device
pivotably about the second pivot axis and are connected together
with at least one yoke, wherein the thrust rod holds the
transmission rocker in the biased position of the drive rocker by
engagement with the yoke when the flap is in its rest position and
the thrust rod enables the travel movement of the yoke when the
flap is deflected out of its rest position at least by a
predetermined amount so that the transmission rocker and the drive
rocker are movable by the biasing spring out of their readiness
position into their rest position.
[0073] In an embodiment of an inhalation device according to the
invention which is particularly protected against unintended
under-dosing, there is further provided a counting device for
detecting the number of delivered drug doses, wherein the counting
device individually detects each dosing operation and the counting
device is connected to a locking device which blocks the inhalation
device upon the attainment of a predetermined number of delivered
doses so that further use is no longer possible and in particular
the closure cap is no longer movable into the closure position.
That can prevent a patient by mistake seeking to inhale from an
inhalation device which no longer has a sufficient stored supply of
medicament. In that way a possibly life-threatening incorrect
dosage can be very substantially avoided. In a different embodiment
of the invention the same advantage will be obtained if the
counting device is connected to the engagement portion of the
trigger device and the stepped stop element of the drive element
has an opening or recess, and the drive element is urged by the
biasing spring to a blocking position, when the engagement portion
engages with the opening or recess. More preferably, the drive
element in its blocking position engages blockingly into the path
of the closure cap so that the closure cap can no longer be moved
into the closure position. Advantageously the counting device
includes a dose-accurate display.
[0074] An inhalation device according to the invention operates
particularly reliably in that respect if the locking device has a
spring-loaded locking element which engages into a groove which is
opened at a predetermined number of doses and in that case
blockingly engages into the mechanism of the actuating element so
that further use of the inhaler is prevented and in particular the
closure cap can no longer be moved into the closure position.
[0075] Particularly clear signalling for an exhausted stored supply
of medicament is achieved even for visually impaired patients if
the locking device is coupled to a signal plate which is displayed
upon blocking engagement into the mechanism of the actuating
element or the actuating element is clearly visibly blocked.
[0076] Particularly preferably the locking device has a
spring-loaded blocking rod which is movable from a rest position
into a blocking position upon the attainment of a predetermined
number of delivered doses and in its blocking position engages
blockingly into the path of the closure cap so that the closure cap
can no longer be moved into the closure position. That arrangement
provides that both a particularly clear signalling action is
achieved and also (futile) further use of the inhalation device and
thus undesirable under-dosing is prevented.
[0077] To provide for efficient moisture protection for the powder
drug disposed in a storage chamber of an inhalation device
according to the invention, it is advantageous if the at least one
storage chamber has at least one outlet opening through which the
powder drug can issue under the influence of the force of gravity,
and a filling opening which is disposed substantially in opposite
relationship to the outlet opening, wherein the filling opening is
sealingly closed.
[0078] In that respect an optimum sealing action which is
independent of component tolerances is achieved if the filling
opening is closed with an aluminium blister film and sealed with a
LDPE layer.
[0079] For short series or for individual operations of filling the
storage chamber, for example in the case of especially produced
galenic preparations of a medicament, it is desirable, in relation
to manual filling, if the filling opening is closed with a cover
which screws to the wall of the storage chamber surrounding the
filling opening and which is sealed in relation to the wall of the
storage chamber with a seal fitted between the cover and the
wall.
[0080] An embodiment of an inhalation device according to the
invention which is both suitable for automation and also better
protected from subsequent manipulation is characterised in that the
filling opening is closed with a cover which is connected by an
injection connection to the wall of the storage chamber which
surrounds the filling opening, wherein an elastic seal or a
yielding sealing rib on the cover and/or the wall is sealingly also
braced between the cover and the wall.
[0081] Particularly good protection from moisture for the powder
medicament is achieved if the storage chamber is at least partially
enclosed by a wall which includes a material with a high level of
water vapour diffusion resistance.
[0082] In a particularly advantageous embodiment which affords
particularly good long-term moisture protection for the medicament
the dosing slider passage has at its one end towards the
environment an opening through which a part of the dosing slider
can pass and a contact surface for a seal is provided around the
opening, wherein the dosing slider has a sealing surface which is
provided in a plane approximately in transverse relationship with
its direction of movement out of the filling position into the
emptying position.
[0083] In that respect it is particularly desirable if an elastic
seal is provided on the dosing slider and/or the contact surface.
Errors upon assembly can be reduced in that respect if the elastic
seal is formed by injection on the dosing slider passage and/or the
dosing slider.
[0084] Alternatively sealing integrity can be formed by a sealing
rib on the dosing slider passage and/or the dosing slider, which is
sealingly deformable by a biasing force which holds the dosing
slider in the dosing slider passage.
[0085] Keeping the medicament dry is improved without mechanically
loading or compacting the medicament powder when shaking the
inhalation device if an encapsulated drying agent is disposed in
the storage chamber, wherein the drying agent body or the drying
agent capsule is fixedly pressed or latched in the cartridge
body.
[0086] Particularly good acceptance in respect of an inhalation
device according to the invention is achieved if the inhalation
device further has a display for signalling inhalation readiness
and/or successful delivery of the medicament.
[0087] An application of particles which can pass to the lungs,
such application being reliable throughout the entire intended
period of use of an inhalation device, even in the event of only
occasional use and cleaning by the user, to achieve satisfactory
hygiene, can be attained by a breaking-down device for breaking
down agglomerates and the like in the drug powder in flow
communication with the mouthpiece and the dosing passage, wherein
the mouthpiece and the breaking-down device are removable for
cleaning by the user and the mouthpiece and the breaking-down
device are so adapted that they can only be removed and fitted
together or are of a one-piece nature.
[0088] The inhalation device of the invention is particularly
useful in a number of medical applications if the at least one
storage chamber is provided by a cartridge holder device and a lid,
wherein the lid has a shape capable of receiving the drug powder
content of the storage chamber in an upside-down position of the
inhalation device. That allows pre-mounting of the cartridge holder
and the dosing slider during manufacture of the inhalation device
including testing. The lid may serve as an open-top cartridge and
filled with the appropriate amount of drug powder in the
pharmaceutical manufacturing line, and directly inserted into the
inhalation device held upside down. So the inhalation device can be
delivered ready to use from the medicament manufacturer.
Preferably, the lid is sealingly fixed onto the cartridge holder by
snap connectors.
[0089] A especially useful embodiment of the inhalation device
according to the invention is characterised in that the cartridge
holder device comprises two storage chambers each covered by a lid,
wherein the cartridge holder device comprises a twin dosing slider.
This allows easy and accurate dosing from two different drug
reservoirs, for instance for the combination of medicaments which
may not be stored together to avoid degradation.
[0090] An inhalation device for powder drugs including at least one
storage chamber for accommodating a plurality of drug powder doses
and a dosing device which includes at least one dosing slider which
is movable approximately with a translatory movement in a dosing
slider passage at least from a filling position into an emptying
position, wherein the inhalation device further includes a device
for inhalation-triggered automatic movement of the dosing slider
from its filling position into the emptying position and a return
device for automatic movement of the dosing slider back into the
filling position.
BRIEF DESCRIPTION OF THE DRAWINGS
[0091] The above mentioned and other features and objects of this
invention, and the manner of attaining them, will become more
apparent and the invention itself will be better understood by
reference to the following description of embodiments of the
invention taken in conjunction with the accompanying drawings,
wherein:
[0092] FIG. 1 shows a perspective view of an embodiment of an
inhalation device according to the invention with the closure cap
closed;
[0093] FIG. 2 shows a perspective view of an embodiment of an
inhalation device according to the invention with the closure cap
opened;
[0094] FIG. 3 shows a perspective view of the cartridge of an
embodiment of an inhalation device according to the invention
illustrating the principle involved;
[0095] FIGS. 4 to 7 show diagrammatic views in section of various
embodiments according to the invention of a closure of a cartridge
from FIG. 3;
[0096] FIG. 8 shows a perspective partial view of an alternative
configuration of the cartridge from FIG. 3;
[0097] FIG. 9 shows a perspective view of a dosing slider for a
cartridge as shown in FIG. 3;
[0098] FIG. 10 shows a diagrammatic view in section of an
alternative arrangement of a dosing slider in a dosing slider
passage of a cartridge as shown in FIG. 3;
[0099] FIG. 11 shows a perspective view of an embodiment of an
inhalation device according to the invention after engagement of
the locking device with the housing removed, with further
components being partially omitted;
[0100] FIG. 12 shows a perspective view of a further embodiment of
an inhalation device according to the invention with the housing
removed, with further components being partially omitted;
[0101] FIG. 13 shows a perspective sectional view of selected
components of FIG. 12;
[0102] FIG. 14 shows a diagrammatic view showing the principle of a
trigger arrangement of an inhalation device according to the
invention;
[0103] FIG. 15 shows a diagrammatic view showing the principle of
another trigger arrangement of an inhalation device according to
the invention;
[0104] FIG. 16 shows a diagrammatic view showing the principle of a
further trigger arrangement of an inhalation device according to
the invention;
[0105] FIG. 17 shows a perspective view of an embodiment of an
inhalation device according to the invention with the closure cap
in the closure position with the housing removed, with further
components being partially omitted;
[0106] FIG. 18 shows a perspective view of an embodiment of an
inhalation device according to the invention with the closure cap
in the operative position with the housing removed, with further
components being partially omitted;
[0107] FIG. 19 shows a perspective view of another embodiment of an
inhalation device according to the invention with the closure cap
in the closure position with the housing removed, with further
components being partially omitted to increase legibility;
[0108] FIG. 20 shows a sectional view of the inhalation device of
FIG. 19;
[0109] FIG. 21 shows an enlarged view of a part of the embodiment
of an inhalation device of FIG. 19 with the housing removed;
[0110] FIG. 22 shows a diagrammatic view showing the principle of
an alternative sliding guide arrangement on a sliding guide carrier
of an inhalation device according to the invention;
[0111] FIGS. 23 to 27 show diagrammatic views showing the principle
of alternative arrangements for the actuation of the dosing slider
on a sliding guide carrier as a drive element of an inhalation
device according to the invention;
[0112] FIGS. 28 and 29 show a perspective view of the embodiment of
an inhalation device of FIG. 19 according to the invention with the
closure cap slightly opened with the housing removed;
[0113] FIG. 30 shows a perspective view of the embodiment of an
inhalation device of FIG. 19 according to the invention with the
closure cap fully opened, with the housing removed;
[0114] FIG. 31 shows a sectional view of the inhalation device of
FIG. 30;
[0115] FIGS. 32 to 36 show diagrammatic views illustrating the
principle of alternative arrangements for the actuation of the
sliding guide carrier;
[0116] FIGS. 37 to 47 show the inhaler from FIGS. 11, 17 and 18 in
various operating conditions in a usual use procedure;
[0117] FIGS. 48 to 54 show the inhalation device from FIGS. 19-21
and 28-31 in various operating conditions in a usual use
procedure;
[0118] FIG. 55 shows an enlarged detailed sectional view of
actuation of a counting device according to the invention with the
embodiment of the inhalation device from FIGS. 19-21, 28-31 and 48
to 54; and
[0119] FIG. 56 is a perspective view of the embodiment of an
inhalation device according to the invention as shown in FIGS. 11,
17 and 18.
[0120] Corresponding reference characters indicate corresponding
parts throughout the several views. Although the exemplifications
set out herein illustrate embodiments of the invention, in several
forms, the embodiments disclosed below are not intended to be
exhaustive or to be construed as limiting the scope of the
invention to the precise forms disclosed.
DETAILED DESCRIPTION
[0121] FIG. 1 shows a perspective view of an embodiment of an
inhalation device according to the invention indicated generally by
reference 1. Such an inhalation device 1 is also referred to as an
inhaler. The inhalation device 1 according to the invention is
provided for the delivery of a large number of individual doses of
a drug in powder form. Special inhalation devices of that kind are
therefore also referred to as powder inhalers and often abbreviated
to MDPI (multi-dose powder inhaler). The inhaler 1 includes a
housing 2. The housing 2 desirably comprises two halves with a
separation line along the central axis along the inhaler 1. That
means that the housing portions can be easily manufactured using
plastic injection moulding and it has been found that, with such an
arrangement, a powder inhaler 1 is simple to assemble. The housing
2 can also include a separate housing cover so that a separate drug
powder cartridge 3 can be subsequently inserted into the assembled
inhaler. The housing cover can then close the housing 2 for example
with a snap connection which is no longer to be released from the
exterior. Such a housing cover can also be removable if it is
desired that the drug powder cartridge 3 is to be replaceable. The
inhaler 1 further includes a closure cap 4 which according to the
invention is non-losably connected to the housing 2. The closure
cap 4 can be pivoted from its closure position into its operative
position by suitable user involvement, about an axis 7. In another
embodiment (FIGS. 12 and 13) the closure cap 4 can be pulled a
distance away from the housing 2 in the longitudinal direction of
the inhaler and preferably pivoted downwardly in order to clear a
mouthpiece 5 disposed therebeneath. An inhalation opening 6 is to
be found in the mouthpiece 5.
[0122] A patient can inhale a drug in powder form through the
mouthpiece 5 by embracing the mouthpiece 5 with his lips and
breathing in through the inhalation opening 6. After inhalation the
closure cap is desirably pivoted back from its operative position
(FIG. 2) into its closure position (FIG. 1) again and possibly
pushed so that it again covers over the mouthpiece 5. In that way
the interior of the inhaler 1 is well protected and preferably
sealingly closed so that no dirt can penetrate into the interior of
the inhaler. As respiration air is usually sucked out of the
inhaler by the patient and thus particles which are disposed in a
movable condition in the interior of the inhaler pass into the
respiratory tract, keeping the interior of an inhaler 1 clean is
extremely important. Furthermore, the ingress of water droplets
into the interior of the inhaler 1 can be substantially prevented
by the closed closure cap 4, for example if a patient is handling
his inhaler in the open air in rainy weather. It is precisely under
such weather conditions that there is frequently a need for
medicational treatment of respiratory tract diseases.
[0123] Furthermore a transparent window 9 for a display 10 of a
counting device 11 is also disposed in the housing 2 of the inhaler
1 on the side at which the mouthpiece 5 and the closure cap 4 are
disposed in the closure position thereof, which hereinafter is
referred as the front side 8 of the inhaler 1. By virtue thereof, a
patient using the inhaler 1 can simply read off the accurate-dosage
number of drug doses which have already been delivered from the
drug supply stored in the inhaler or preferably an accurate-dosage
number of the drug doses still available from the drug supply is
displayed in such a way that it can be easily read off. In that
fashion the patient is in a position to attend to replacement in
good time if for example the number of remaining doses is no longer
sufficient for the duration of a vacation journey. Experience has
shown that such powder inhalers 1 are used in particular in
relation to chronic diseases of the respiratory tract or other
chronic diseases in relation to which medicaments can be
administered by way of the respiratory tract, and frequently
regular inhalation of a medicament is vitally necessary for the
patient. A high degree of reliability in terms of the drug doses
available by way of the inhaler 1 is therefore essential for such
patients.
[0124] Furthermore, also displayed at the front side 8 at the
inhaler 1 is a readiness display 12 which can also be seen through
a transparent window 9 for showing that the inhaler 1 is ready to
deliver a drug dose, and for displaying that a drug dose has been
successfully dispensed from the inhaler 1. Preferably operational
readiness or successful administration of a drug dose is signalled
by a colour change, in which respect a green representation has
proven appropriate for displaying operational readiness and a
colour change to a red representation has proven appropriate for
displaying successful administration. At the same time the red
representation signals that the inhaler 1 is first to be prepared
for renewed inhalation. In the case of the inhaler 1 according to
the invention that is particularly preferably effected by actuating
the closure cap 4 from the closure position into the operative
position.
[0125] The provision of transparent windows 9 instead of usual
openings affords particular protection from the ingress of
contamination and impurities and moisture. The arrangement of the
windows 9 for the display 10 and the readiness display 12 as well
as the closure cap 4 which is preferably pivoted downwardly in the
operative position also encourages a patient to hold the inhaler 1
correctly upon inhalation so as to ensure reliable dosing and
delivery of a powder drug. Preferably in that respect the
dimensioning is so selected that, when the inhaler is held
inverted, the closure cap 4 which in the operative position
collides with the nose of the patient if the latter endeavours to
close the lips around the mouthpiece 5.
[0126] Alternatively the display 10 and/or the readiness display 12
can also be so arranged that they are covered over by the closure
cap 4 in the closure position thereof. That makes it possible to
achieve good protection from the ingress of contamination and water
droplets even without additional transparent window elements.
[0127] In its interior the inhaler 1 includes a storage chamber 13
for accommodating a plurality of drug powder doses. The storage
chamber 13 can desirably be formed in a cartridge 3. The
arrangement of the storage chamber 13 in a separate cartridge 3 has
the advantage that the inhaler 1 according to the invention can be
manufactured and assembled independently of filling thereof with
the powder drug and that manufacturing and assembly procedure does
thus not have to be implemented under pharmaceutical cleanliness
conditions. The separate cartridge 3 can be filled under suitable
cleanliness conditions and later fitted to the inhaler 1. In
addition that concept makes it possible to offer an inhaler 1 with
different powder drugs without this meaning that manufacture and
assembly of the inhaler, except for the cartridge 3, have to be
implemented at the location of manufacture or filling of the
corresponding drug. In addition this concept makes it possible for
example for inhalers 1 to be kept in stock without the cartridge 3
and for cartridges 3 possibly even to be individually filled with
galenic individual preparations of medicaments and fitted into the
inhaler 1 from the supply in stock and made available to the
patient.
[0128] The drug powder cartridge 3 shown in FIG. 3 with the storage
chamber 13 includes an outlet opening 14 through which the powder
drug can issue under the influence of the force of gravity.
Furthermore a dosing device which includes a dosing slider 15 is
desirably integrated into the cartridge 3. The dosing slider 15 can
occupy in a dosing slider passage 16 a filling position (as can be
seen for example in FIG. 17) in which a dosing cavity 17 is under
the outlet opening 14 so that the powder medicament 18 in the
storage chamber 13 can pass into the dosing cavity 17 under the
influence of the force of gravity. Furthermore the dosing slider 15
is movable in the dosing slider passage 16 into an emptying
position (shown in FIG. 3) in which the outlet opening 14 is closed
by the dosing slider 15 and the dosing cavity 17 issues from the
dosing slider passage 16 to such an extent that the drug powder can
be taken from the dosing cavity 17 by an air flow. The movement of
the dosing slider 15 from the filling position into the emptying
position and from the emptying position into the filling position
is effected with a translatory motion along the axis of the dosing
slider passage 16. The dosing slider passage 16 has a closed bottom
which at the same time forms the bottom of the dosing cavity 17
during the operation of filling the dosing cavity 17 in the filling
position of the dosing slider 15.
[0129] In addition the storage chamber 13 of the cartridge 3 has a
filling opening 19 which is desirably disposed in opposite
relationship to the outlet opening 14. The opening 19 serves to
introduce the powder medicament into the storage chamber 13 in the
required number of doses. The filling opening 19 is sealingly
closed after the filling operation in order to ensure the purity of
the medicament powder and to prevent the ingress of foreign
substances. Desirably the filling opening 19 is closed with an
aluminium blister layer 20 and the latter is sealed with an LDPE
layer 21 comprising a low density polyethylene (FIG. 4). That
manner of closing the opening can be carried out particularly well
automatically and also affords the great advantage that that
closure of the filling opening 19 is very substantially
impenetrable for water vapour.
[0130] In practice it has been found that it is particularly
important for the drug supply in the storage chamber 13 to be
protected as well as possible from the ingress of moisture. There
are a number of reasons for that. On the one hand the medicament
can alter with interaction with moisture and in particular the
medical effectiveness thereof can be impaired while on the other
hand absorption of moisture in the drug powder easily results in
lump formation so that it is difficult to achieve reproducible
reliable dosage of the drug in use. Frequently such inhalers 1 are
also used for diseases which do not constantly require medicament
administration but in respect of which a suitable medicament has to
be kept in readiness. In particular allergic diseases of the
respiratory tract are to be considered in that respect. That means
that the medicament 18 in the stored supply must remain stable and
reliably dosable over a long period of time, even if a patient
daily carries such an inhaler 1 about his person in his jacket
pocket. The closure according to the invention for the filling
opening 19 provides such long-term protection for the stored supply
of medicament from the ingress of moisture.
[0131] Particularly for the individual preparation of medicaments
and filling thereof into a suitable cartridge 3, as already
referred to hereinbefore, it may also be desirable for the filling
opening 19 to be closed after the filling operation with a screw
cover 22 and for a corresponding screwthread to be provided in the
wall 23 of the cartridge 3, surrounding the filling opening 19
(FIG. 5). Desirably fitted between the cover 22 and the wall 23 is
a seal 24 which for example can be made from a suitable TPE.
Instead of an elastic seal 24 however it is also possible to
provide a sealing rib 25 on the cover 22 or the wall 23 (see FIG.
6) which, when the cover 22 is fitted, is sealingly also braced
between the cover 22 and the wall 23 and in that case is
elastically or plastically deformed. By virtue of the arrangement
with a screw cover 22, it is also possible for short series of
cartridges 3 to be filled with a given medicament by hand and
closed.
[0132] For automated filling however it may also be desirable to
provide a cover 26 instead of a screw cover 22 and to join it to
the wall 23 for example by ultrasound welding or to glue it in
place (FIG. 6).
[0133] Particularly in filling processes which are carried out on a
large technical scale however it may also be desirable for the
cover to be in the form of a snap cover 27 and for a hook
arrangement 28 and a groove 29 to be provided in the wall 23 and
the snap cover 27 respectively, thus forming a spreading latching
engagement or snap connection (FIG. 7). Preferably the groove 29
and the hook arrangement 28 are so arranged that, after fitment of
the snap cover 27, as far as possible they can no longer be reached
even with a tool so that after fitment the snap cover 27 can no
longer be removed without destroying the cartridge. In the case of
such a latching connection also it is desirable for an elastic seal
24 or a sealing rib 25 which upon assembly is also sealingly braced
to be provided between the snap cover 27 and the wall 23.
[0134] Since, as already mentioned, the aim is to achieve a high
level of sealing integrity for the cartridge 3 in relation to the
ingress of moisture out of the ambient atmosphere it is desirable
if the wall 23 includes a material which affords a particularly
high level of water vapour diffusion resistance. Preferably however
that material should still be suitable for processing by
appropriate inexpensive production processes, for example by
injection moulding. Some suitable materials are described for
example in US 2003 013 64 05 A, to which reference is hereby
directed.
[0135] Furthermore, for comprehensive moisture protection for the
medicament 18 in the storage chamber 13 of the cartridge 3, it is
advantageous in accordance with the invention that the dosing
slider passage 16 has a corresponding opening 30 at its open end
through which the dosing slider 15 can issue with the dosing cavity
17, wherein a contact surface 31 for a seal 32 is provided around
the opening 30 and wherein the dosing slider 15 further has a
sealing surface 33 which is arranged in a plane in approximately
transverse relationship with the direction of movement out of the
filling position into the emptying position (FIG. 8). In that
respect it is equivalent from the point of view of the sealing
function whether the elastic seal 32 is disposed on the contact
surface 31 or the sealing surface 33 of the dosing slider 15, as
shown in FIG. 9. Desirably the elastic seal 32 comprises a
thermoplastic elastomer which is preferably injection moulded in a
multi-component injection moulding procedure directly on the dosing
slider 15 or the dosing slider passage 16. It will be appreciated
however that it is also possible to provide a separate seal. The
arrangement of the dosing slider 15 in the dosing slider passage 16
with the seal 32 can be seen from FIG. 3. Desirably the dosing
slider 15 is also secured in its filling position by spring
elements 34 so that the seal 32 is always slightly prestressed when
the dosing slider 15 is in its filling position. That is
particularly advantageous as long as the cartridge 3 is stored or
transported outside the inhaler 1 in order always to achieve an
optimum sealing action.
[0136] As an alternative to the elastic seal 32 a sealing rib 35
can also be formed on the dosing slider passage 16 or the dosing
slider 15, as shown in FIG. 10. In that case the sealing rib 35
will be sealingly deformed by the biasing force which holds the
dosing slider 15 in its filling position in the dosing slider
passage 16 (FIG. 10).
[0137] So that, in spite of the above-described numerous and
effective measures which very substantially prevent moisture from
penetrating into the storage chamber 13 of the cartridge 3, any
residual moisture can be absorbed or a moisture level which is
required by virtue of particular properties of the medicament 18
can be set, a drying agent body or an encapsulated drying agent 36
can be disposed in the storage chamber 13 of the cartridge 3.
Desirably the drying agent body or the drying agent capsule is
pressed or latched in the storage chamber 13 of the cartridge 3.
That measures holds the drying agent 36 away from the medicament
powder 18 and in particular prevents the medicament powder 18 being
mechanically loaded by the drying agent 36 in the event of
vibration, shaking or shocks, in particular to prevent the
medicament powder 18 from being compacted. That means that
particularly reproducible dosing of the medicament powder 18 is
possible, and also bridge formation of the medicament powder 18
over the outlet opening 14 is prevented and thus the overall
reliability of the inhaler 1 according to the invention is
improved.
[0138] Instead of the above-described preferred arrangement of a
drying agent 36 in the storage chamber 13, a solid drying agent
body, for example an injection moulded body of plastic material in
which a drying agent is embedded, can be fixedly fitted in the form
of a sleeve into the storage chamber 13. In addition a drying agent
body can also be fixedly integrated in the cover 22, 26 or 27.
Finally a drying agent 36 can also be incorporated as a component
in a multi-component injection moulding procedure for manufacturing
the wall 23 of the storage chamber 13.
[0139] The structure in greater detail of an embodiment of an
inhaler 1 according to the invention can be seen in FIG. 12. For
the purposes of description the housing 2 and some further parts
have been omitted from the illustrated view. FIG. 13 shows a
sectional view of the inhaler 1 of FIG. 12. By way of example, but
not necessarily so, the cartridge 3 with the storage chamber 13 for
accommodating the plurality of drug powder doses is arranged in the
rear region of the inhaler housing 2, as already described in
detail hereinbefore. In addition the inhaler 1 includes a device
for inhalation-triggered automatic movement of the dosing slider 15
out of a filling position into the emptying position and a return
device for automatic movement of the dosing slider 15 back into the
filling position within the dosing slider passage 16.
[0140] Those devices are described in greater detail hereinafter.
Provided at the front end of the inhaler is the mouthpiece 5 which,
as already mentioned, can be covered over by a closure cap 4. The
inhalation opening 6 is provided in the mouthpiece 5. The
mouthpiece 5 with the inhalation opening 6 is in flow communication
with a dosing passage 38. A patient can suck an airflow through the
dosing passage 38 upon inhalation and, by way of the dosing
passage, receives the applied dose of a drug powder which is
apportioned with the dosing cavity 17 of the dosing slider 15. In
addition the mouthpiece 5 is in flow communication with an air
passage 39. Provided within the mouthpiece 5 is a breaking-down
device 40, for example in the form of a cyclone arrangement (see
FIG. 13). The breaking-down device 40 is connected to the dosing
passage 38 so that an airflow loaded with the medicament powder
passes into the breaking-down device 40 from the dosing passage 38.
The airflow is preferably strongly deflected a plurality of times
in the breaking-down device 40 in order to break down agglomerates
or similar accumulations of medicament powder so that the patient
very substantially receives through the mouthpiece 5 drug particles
which are of a uniform lung-negotiating particle size. In the
embodiment shown in FIG. 13, with a parallel flow feed for the air
in the dosing passage 38 and the air passage 39, the airflows
thereof are brought together in the mouthpiece 5. In the embodiment
shown inter alia in FIGS. 11, 17 and 18, the parallel flow path is
omitted and the dosing passage 38 forms a part of the air passage
39.
[0141] In long-lasting use it is advantageous if the patient can
remove and easily clean the mouthpiece S and the breaking-down
device 40 without a tool, for example under a water tap. That is
desirable in order for example to remove residues formed by
respiration moisture, saliva or the like, with drug powder, from
the mouthpiece and the breaking-down device 40. Bacteria or the
like can also be introduced into the mouthpiece by the patient by
way of the mouth, and they can also be removed in that fashion. In
that respect it may also be desirable for the patient to be
afforded for example a suitable cleaning solution.
[0142] After cleaning and possibly drying of the mouthpiece 5 and
the breaking-down device 40 the patient re-fits those parts into
the inhaler 1 in order to restore the inhaler 1 to full operability
again. In that respect it is extremely important in terms of the
effectiveness of medicament absorption that the breaking-down
device 40 is in actual fact also fitted again and not for example
the mouthpiece 5 without the breaking-down device 40. If the
breaking-down device 40 is missing, there is the risk that the
medicament powder is not sufficiently broken down into particles
which can pass into the lungs, and accordingly the effectiveness of
medicament administration is unexpectedly reduced. In order to
prevent operating errors by patients who are also clumsy or
unskilled the inventors found that it is desirable for the
mouthpiece 5 and the breaking-down device 40 to be designed in such
a way that they can only be removed and re-fitted jointly. That can
be achieved by for example the mouthpiece 5 and the breaking-down
device 40 being joined together upon assembly of the inhaler 1, by
the formation of a snap-action connection, in such a way that a
patient can no longer take those parts apart without destroying
them. That is particularly suitable when the mouthpiece 5 and/or
the breaking-down device 40 are of a configuration which is
complicated from the production engineering point of view as that
arrangement affords the advantage that the two parts can be
manufactured separately. Particularly to reduce assembly costs and
to avoid gaps and joins which possibly cannot be correctly cleaned
or then dried, it is desirable for the mouthpiece 5 and the
breaking-down device 40 to be produced in one piece for example by
suitable shaping processes.
[0143] When a patient begins to draw in an airflow through the
mouthpiece the dosing passage 38 is firstly closed by a valve
device 41, in which respect the valve device can also be formed by
another part of the inhaler being pushed in the manner of a slider
into the flow path of the dosing passage 38 or by a corresponding
opening being covered over. When now a patient begins with
inhalation, a corresponding reduced pressure or airflow is firstly
built up in the air passage 39.
[0144] Disposed in the air passage 39 is a trigger device which is
described in greater detail hereinafter. That trigger device serves
to signal when a predetermined minimum airflow in the air passage
39 is exceeded, in which case that minimum airflow can also be
formed by the production of a predetermined reduced pressure in the
air passage 39. Preferably, the air passage 39 is of a markedly
enlarged flow cross-section in the region of the trigger device. In
that way it is possible to produce comparatively high and uniform
control forces with an element which for a large part closes the
flow cross-section, even in the event of a comparatively low
reduced pressure and with a low degree of scatter. In a preferred
embodiment the trigger device includes a flap 42 pivotably mounted
in the air passage 39. As already mentioned, in the region of the
flap 42 the air passage 39 is of a cross-section which is
particularly large in relation to the dosing passage 38. The flap
42 is held in the starting position preferably directly or
indirectly by a spring loading. In a particularly advantageous
feature the flap 42 is pivotable about a pivot axis 80 and the
pivot axis 80 extends through or close to the centre of gravity of
the flap 42. That provides that the flap 42 is balanced about the
pivot axis 80 and thus, in the event of a knock against the inhaler
1, for example if the inhaler 1 is dropped, no moments induced by
the mass of the flap 42 are generated around the pivot axis 80.
[0145] As can be seen from the diagrammatic view in FIG. 13 the
flap 42 is coupled to a thrust rod 43. The thrust rod 43 is
operatively connected to a device for inhalation-triggered
automatic movement of the dosing slider 15, wherein the device for
inhalation-triggered automatic movement of the dosing slider 15 is
held directly or indirectly in a biased position by the thrust rod
43 when the flap 42 is in its rest position. The thrust rod 43 is
actuated by the flap 42 when the flap 42 is moved by an inhalation
flow in the air passage 39 by the patient. As will be described in
greater detail hereinafter the thrust rod 43 releases the device
for inhalation-triggered automatic movement of the dosing slider 15
when the flap 42 is deflected out of its rest position at least by
a predetermined amount. That provides that the device for
inhalation-triggered automatic movement of the dosing slider 15 is
activated when a certain minimum airflow or minimum air pressure
has been built up in the air passage 39 by the patient. The
magnitude of the required minimum airflow or minimum reduced
pressure in the air passage 39 can be set in that case by the
effective cross-section of the flap 42 and a closing force which is
to be overcome. In that respect the closing force can desirably be
applied by a spring 99, connected to the flap 42 or the thrust rod
43 and holding the flap 42 in its rest position and therewith the
thrust rod 43 in the position in which the device for
inhalation-triggered automatic movement of the dosing slider 15 is
held in its biased position by the thrust rod 43. In that case the
thrust rod 43 can be directly or indirectly connected to the device
for inhalation-triggered automatic movement of the dosing slider 15
and can be for example angled, or may have a shape of a bent fork,
depending on how the device for inhalation-triggered automatic
movement of the dosing slider 15 is respectively structurally
designed and in what direction the thrust rod 43 is displaced by
the flap 42.
[0146] As will be described in greater detail hereinafter that
makes it possible to administer an appropriate close of medicament
to the patient at a time when the patient has built up a
sufficiently great inhalation airflow in order to ensure that the
greatest part of the medicament powder which is inhaled can pass
into the lungs. In that way the moment of dose administration of
the drug powder can be optimised completely independently of the
operating behaviour and the co-ordination capabilities on the part
of the patient and a very high level of reliability and efficiency
in terms of medicament delivery to the patient is achieved
irrespective of the capabilities or understanding on the part of
the patient for the processes involved during inhalation. That not
only enables an inhaler 1 according to the invention to be used in
relation to a particularly wide circle of people, but an inhaler 1
according to the invention is therefore also particularly suitable
for patients with whom medicament administration has to be effected
reliably when shock conditions occur or under other panic
conditions, for example in the case of spontaneous attacks. With
the inhaler according to the invention a patient needs to do
nothing other than suck on the mouthpiece 5 in order to receive an
administration of the medicament powder which is adapted for
optimum lung-negotiating capability.
[0147] A particularly compact arrangement and simple assembly can
be achieved in that respect if the coupling between the flap 42 and
the thrust rod 43 is formed by a toothed ring segment 44 on the
flap 42 and a portion 45 on the thrust rod 43, that is in the form
of a toothed rack. That arrangement and the arrangement of the
dosing passage 38 and the air passage 39 can be clearly seen from
FIG. 13.
[0148] The connection between the flap 42 and the thrust rod 43 can
also be made in another suitable fashion, for example by means of a
groove or opening into which an entrainment portion of the
respective other part engages (FIG. 14). in an alternative
embodiment which is diagrammatically shown in FIG. 15 the flap 42
is pivotable about an axis 46, wherein the axis is arranged at some
distance from an end of the flap 42. The flap 42 has a claw which
is pivotable together with the flap 42 about the axis 46 and which
holds a spring-loaded securing element 47 and the contact face of
which with the securing element 47 is formed by way of a sliding or
rolling pairing, for example by a roller 48. The securing element
47 is in turn operatively connected to the device for
inhalation-triggered automatic movement of the dosing slider 15, as
already described hereinbefore, so that the device for
inhalation-triggered automatic movement of the dosing slider 15 is
released when the flap 42 is deflected out of its rest position by
at least a predetermined amount by virtue of the inhalation flow on
the part of the patient.
[0149] The trigger device can also have a piston 49 which is
connected to the air passage 39 so that the face of the piston is
acted upon by the reduced pressure which is applied by the patient.
With such an arrangement the thrust rod is desirably formed by a
piston rod 50. Desirably the piston in turn is of a comparatively
large cross-sectional area in order reliably to release the device
for inhalation-triggered automatic movement of the dosing slider 15
when the piston is deflected out of its rest position at least by a
predetermined amount by the predetermined minimum airflow initiated
by the patient in the air passage 39. Such an arrangement is
diagrammatically shown in FIG. 16.
[0150] The device for inhalation-triggered automatic movement of
the dosing slider 15 out of its filling position into the emptying
position will be described in greater detail hereinafter with
reference to the embodiment shown in FIGS. 12 and 13 of an inhaler
1 according to the invention. Desirably the dosing slider 15
includes entrainment projections 51, preferably at both sides
transversely with respect to the direction of movement of the
dosing slider 15. Those entrainment projections 51 of the dosing
slider 15 co-operate with corresponding recesses of an actuating
device for the dosing slider in the inhaler. In an advantageous
embodiment those recesses are formed by two sliding guides 52 in a
sliding guide carrier 53 as a drive element. The sliding guide
carrier 53 is formed by a kind of frame which desirably embraces
the lower region of the cartridge 3 on both sides (FIG. 12).
[0151] The sliding guide carrier 53 can assume a rest position, in
the illustrated embodiment this involves an upper position. The
sliding guide carrier 53 is held in that rest position by a biasing
spring 54, wherein the biasing spring 54 is almost or completely
relieved of stress when the sliding guide carrier 53 is in its rest
position. The sliding guide carrier 53 can be moved into a
readiness position, in the illustrated example in the lower
position, against the force of the biasing spring 54. In that
arrangement the sliding guide 52 includes a sliding guide portion
55 which is vertical in the position of use of the inhaler so that
a relative movement is possible between the sliding guide carrier
53 and the entrainment projection 51 of the dosing slider 15
without the dosing slider 15 being moved out of its filling
position.
[0152] Desirably the region of the sliding guide carrier 53 which
includes the vertical sliding guide portion 55 is elastically
deformable transversely with respect to the direction of movement
of the sliding guide carrier 53. The vertical sliding guide portion
55 is of a depth which decreases in an upward direction and which
in the upper region 56 of the vertical sliding guide portion forms
a step, above which the sliding guide is again of the initial
depth. When now the sliding guide carrier 53 is moved out of its
rest position downwardly into its readiness position, the wedge
effect of the upwardly decreasing depth of the vertical sliding
guide portion 55 of the corresponding regions of the sliding guide
carrier provide that the entrainment projections 51 of the dosing
slider 15, which run in the vertical sliding guide portion 55, are
elastically spread and snap back into their original position again
as soon as the entrainment projections 51 have reached the upper
region 56 of the vertical sliding guide portion 55 and have thus
passed the step.
[0153] That arrangement is intended to ensure that, in a return
movement of the sliding guide carrier 53 from its readiness
position into its rest position, that is to say upwardly in the
selected example, the entrainment projections 51 of the dosing
slider 15 cannot run back in the vertical sliding guide portion
55.
[0154] The upper region 56 of the sliding guide 52 is connected to
an oblique sliding guide portion 57 which is inclined with respect
to the vertical sliding guide portion 55. When now the sliding
guide carrier 53 moves out of the lower readiness position into the
upper rest position, that is to say upwardly, the entrainment
projections 51 of the dosing slider 15 are guided in the inclined
sliding guide portion 57 so that, with a transmission relationship
determined by the inclination of the inclined sliding guide portion
57 with respect to the direction of movement of the sliding guide
carrier 53, the dosing slider 15 is entrained from its filling
position into its emptying position in positively guided
relationship. Disposed between a lower end of the inclined sliding
guide portion 57 and the lower end of the vertical sliding guide
portion 55 is a horizontal sliding guide portion 58 which connects
the lower end of the inclined sliding guide portion 57 to the lower
end of the vertical sliding guide portion 55. When the sliding
guide carrier 53 reaches its upper rest position the dosing slider
15 can move with its entrainment projections 51 in the horizontal
sliding guide portion 58 between its emptying position and its
filling position. Desirably the dosing slider 15 is connected to a
return spring 59 which draws the dosing slider 15 back into its
filling position, when the upper rest position of the sliding guide
carrier 53 is reached.
[0155] In its readiness position a portion 41 of the sliding guide
carrier 53 covers over the dosing passage 38 above the location at
which the dosing slider 15 briefly issues into the dosing passage
38. The sliding guide carrier therefore serves as a valve device 41
in order substantially to close the dosing passage 38 as long as
the sliding guide carrier 53 is in its readiness position. As soon
as the trigger device in the form of the flap 42 and the thrust rod
43 releases the sliding guide carrier 53 and therewith the valve
device 41 and the sliding guide carrier 53 moves in a direction
towards its rest position, the substantial part of the flow
cross-section of the dosing passage 38 is opened. As a result, upon
the beginning of an inhalation by a user of the inhalation device,
a suction airflow is firstly built up in the air passage so that,
upon inhalation-triggered opening of the dosing passage
cross-section, there is already a suction airflow and the air does
not have to be first accelerated and a reduced pressure built up.
As the air passage 39 is substantially closed by the deflected flap
42, the substantial part of the airflow through the dosing passage
38 and in particular through the dosing cavity 17 of the dosing
slider 15 now takes place during the time in which the dosing
slider 15 is moved by the sliding guide carrier 53 into its
emptying position. As a result, within a short period of time, it
is possible to ensure complete emptying of the dosing cavity 17 and
efficient introduction of the medicament in powder form into the
lungs of a patient can be achieved.
[0156] The desirable embodiment is described with a sliding guide
carrier 53 guided linearly in the housing 2. To avoid friction and
jamming with unsuitable material pairing which can be caused by
manufacture for example or can be caused by virtue of particular
properties of the medicament, the drive element can also be in the
form of a drive rocker 82. In order to achieve a movement which is
as little curved as possible, it is desirable for the length of the
rocker to be selected to be as great as possible. The possible
rocker length however is greatly limited by the structural length
of the inhaler 1. The effective rocker length can be markedly
increased in relation to the actual available structural length by
means of a multi-link arrangement as is known from the vehicle
industry by the term Paralever. That however entails a
corresponding increase in expenditure in terms of individual parts
and assembly insofar as the links cannot be embodied by integral
film hinges.
[0157] It is basically also conceivable for the dosing slider 15 to
be connected directly to the flap 42 so that a movement of the flap
42 is transmitted directly to the dosing slider 15. It will be
noted however that this requires complicated assembly procedures
and the cartridge 3 cannot be so easily subsequently fitted into a
completely pre-assembled inhaler 1.
[0158] Instead of the described sliding guide configuration and
return of the dosing slider 15 to its return position by way of a
return spring 59, the sliding guide 52 of the sliding guide carrier
53, instead of the inclined sliding guide portion 57, can have a
v-shaped sliding guide portion 60 which, for the entrainment
projections 51 of the dosing slider 15, forms a positive guidance
means for movement from its filling position into its emptying
position and back into the filling position when the sliding guide
carrier is moved out of the readiness position into the rest
position (FIG. 22). The vertical sliding guide portion 55 is
however also required in that case so that the sliding guide
carrier 53 can be moved against the force of the biasing spring 54
into its readiness position without the dosing slider 15 leaving
its filling position.
[0159] The sliding guides can also be in the form of cam portions
in particular in conjunction with a dosing slider 15 which is
loaded by a return spring 59. It is particularly desirable if the
sliding guide portions are of a rectilinear configuration. However,
to achieve a desired transmission ratio, for example to take
account of the travel-dependent actuating force when moving the
sliding guide carrier 53 out of its readiness position into the
rest position, it may also be desirable for the sliding guides to
be of a curved configuration, in particular eccentrically curved.
In conjunction with a rotational movement it may also be desirable
if the sliding guide or the cam portion is of a helical
configuration.
[0160] The dosing slider 15 can also be moved from its filling
position into the emptying position by a cyclically controlled cam
or sliding guide wheel and can desirably be retracted by the return
spring 59. In the case of a rotational arrangement the sliding
guide carrier 53 can also have an eccentrically dosed sliding guide
and can positively guide the dosing slider 15 between the filling
and emptying positions by way of the entrainment projections 51. In
the case of a rotating sliding guide carrier 53 it is also possible
to provide a cam arrangement, by way of which the dosing slider is
moved out of the filling position into the emptying position and
desirably retracted by the return spring 59. It is also possible to
provide a corresponding arrangement with an eccentric cam disc.
Corresponding arrangements are diagrammatically shown in FIGS. 23
to 27.
[0161] Direct coupling of the dosing slider 15 and the flap 42 or
piston 59 for movement of the dosing slider out of the filling
position into the emptying position, preferably in conjunction with
the return spring 59, is also conceivable.
[0162] The actuating energy for the movement of the sliding guide
carrier 53 out of its readiness position into the rest position is
desirably afforded by way of the biasing spring 54. By means of
suitable actuating devices a user of the inhaler 1 can store that
necessary actuating energy in the device insofar as the sliding
guide carrier 53 is moved from its rest position into its readiness
position against the force of the biasing spring 54. That is
described in greater detail hereinafter.
[0163] The sliding guide carrier 53, as part of the device for
inhalation-triggered automatic movement of the dosing slider 15 out
of its filling position into the emptying position, is arrested in
its readiness position by the trigger device which has already been
further described in greater detail herebefore. Desirably for that
purpose the thrust rod 43 which has already been described in
greater detail engages into a corresponding recess or projection of
the sliding guide carrier 53 as soon as the sliding guide carrier
53 has reached its readiness position. The sliding guide carrier 53
can only return to its rest position when, by virtue of a
sufficiently high level of inhalation suction flow, the flap 42 is
deflected and the thrust rod 43 is moved sufficiently far that it
comes out of engagement with the sliding guide carrier 53 and the
sliding guide carrier 53 can be moved by the force of the biasing
spring 54 out of its readiness position into the rest position.
[0164] Desirably the biasing spring 54 is in the form of a leaf
spring (see FIG. 56) or a shaped spring. Such a spring can be
easily produced, it can be of a contour which is adapted to the
space circumstances in the inhaler and it can possibly be formed by
a suitable plastic material which is also fibre-reinforced, and can
be in one piece with other components of the inhaler, for example
by injection moulding. Such a one-part configuration together with
the sliding guide carrier 53 or a part of the housing 2 would be
desirable. In the same fashion the return spring 59 for the dosing
slider 15 can also be in the form of a leaf spring or shaped
spring.
[0165] When constricted lateral space circumstances are involved,
it may also be desirable if the biasing spring 54 and/or the return
spring 59 is in the form of a coil spring. In particular that
structural configuration is appropriate for the return spring 59.
It may also be desirable, in particular in conjunction with a
rotationally actuated drive rocker 82, if the biasing spring 54
and/or the return spring 59 is a spiral spring or a torsion spring.
Particularly for the return spring 59 but also for the biasing
spring 54, it may also be desirable if it is an elastically
deformable shaped body. For that purpose, for example in relation
to the return spring 59, it is appropriate to injection-mould on
the dosing slider 15 such a shaped body, for example in the form of
a suitable thermoplastic elastomer, which can then serve as a
fraction spring. It may also be desirable for the biasing spring 54
if it is injection-moulded for example in the form of an
elastically deformable shaped body on the sliding guide carrier 53
or the bottom of the housing 2.
[0166] In particular for the biasing spring 54 it is also
appropriate for that spring to be formed by a compressed air
storage means. Here for example a part of the sliding guide carrier
53 can be in the form of a piston which engages into a hermetically
closed cylinder so that the volume of air in the cylinder is
compressed when the sliding guide carrier 53 is moved from its rest
position into the readiness position. As soon as the sliding guide
carrier 53 is released by the trigger device the volume of air in
the cylinder can expand and thus drive the sliding guide carrier 53
into its rest position.
[0167] In order to achieve uniform actuating forces for the dosing
slider 15 it may be desirable for the biasing spring 54 to have a
non-linear spring characteristic.
[0168] In accordance with the invention there are a number of
possible options for operating devices, by which a user of the
inhaler 1 can move the sliding guide carrier 53 from its rest
position into its readiness position against the force of the
biasing spring 54. One possible option is for the biasing force to
be applied by means of a rotary knob 61 coupled to an entrainment
portion 62, by way of which the sliding guide carrier 53 is
displaced out of its rest position into the readiness position when
the rotary knob 61 is turned. The actuating force can be altered,
with the biasing force of the biasing spring 54 remaining the same,
by the spacing of the entrainment portion 62 from the axis of
rotation of the knob 61. It will be appreciated however that
limitations in terms of structural space are to be taken into
consideration. Such an arrangement is shown in the diagrammatic
view in FIG. 32.
[0169] Actuation of the sliding guide carrier can also be effected
by way of an actuating button 63 which can act directly with a
translatory movement on the sliding guide carrier 53 or which can
act on the sliding guide carrier 53 by way of rotary pivot point.
In the last-mentioned variant the actuating force required with a
given biasing force of the biasing spring 54 can be set by
adjustment of the lever lengths. It will be appreciated that such
an arrangement also involves a limitation due to the structural
space in the housing 2 of the inhaler 1. Such a view is shown in
principle in FIG. 33.
[0170] It is particularly preferred in accordance with the
invention however for actuation of the sliding guide carrier 53
from its rest position into the readiness position to be coupled to
the movement of the closure cap 4 out of the closure position into
the readiness position. As already mentioned the protective or
closure cap 4 is non-losably connected to the inhalation device.
Desirably the closure cap 4 includes two pairs of entrainment
portions 64 which are arranged at the rearward portion 65 of the
closure cap 4. In the embodiment of an inhaler 1 according to the
invention as shown in FIGS. 12 and 13 a pair of those entrainment
portions 64 run in a sliding guide 66 in the housing 2. That
firstly makes it possible for the closure cap to be guided in the
longitudinal direction from the front side 8 of the inhaler 1 until
the closure cap 4 can be pivoted downwardly past the mouthpiece 5.
In that case longitudinal mobility of the closure cap 4 with
respect to the housing 2 is achieved by way of the preferably
linear sliding guide 66. A further pair of entrainment portions 64
co-operate with an actuating sliding guide 67, which is
complementary thereto, in the sliding guide carrier 53. In that
arrangement the actuating sliding guide 67 includes an inclined
sliding guide portion which is so inclined that it falls away
rearwardly, as viewed from the front side 8 of the inhaler, and is
open downwardly. When the sliding guide carrier is in its rest
position and the closure cap is in its closure position the
entrainment portion 64 engages into the rear lower end of the
inclined sliding guide portion. If now the closure cap 4 is pulled
forwardly in order to be pivotable past the mouthpiece 5, the
sliding guide carrier 53 is actuated by the longitudinal movement
of the closure cap and therewith the pair of entrainment portions
64, by way of the inclined sliding guide portion 68, from its rest
position into the readiness position downwardly against the force
of the biasing spring 54. The closure cap 4 can now be pivoted into
its operative position and the mouthpiece 5 is accessible to the
patient to carry out an inhalation process. When inhalation is
successfully effected the sliding guide carrier 53 moves back into
its rest position. The closure cap can now be pivoted upwardly and
pushed rearwardly into the inhaler. In that case the entrainment
portions 64 come into engagement again with the rear lower end of
the inclined sliding guide portion 68 of the sliding guide carrier
53. That can be seen from the diagrammatic view in FIG. 34.
[0171] The actuating sliding guide 67 in the sliding guide carrier
53 desirably also has a second sliding guide portion 69 which
extends substantially horizontally, in particular parallel to the
sliding guide 66 in the housing 2. That second sliding guide
portion 69 does not have a direct function but only serves to
afford the patient the possible option of being able to move the
closure cap 4 into the closure position again without successful
inhalation having been effected. With that configuration the
sliding guide carrier 53 is still in its lower readiness position
and without the second sliding guide portion 69 the closure cap 4
could not be pushed rearwardly, with the entrainment portions 64.
Such a functional extent is particularly desirable to provide that
for example a pharmacist can demonstrate handling of the inhalation
device without a dose having to be directly taken therefrom. As a
dose could only be inhaled by an adequate inhalation airflow, that
would otherwise have the result that a patient would have to inhale
a dose of a medicament, at a time which is possibly not prescribed
by the physician. Desirably, the second sliding guide portion 69 is
closed at its end so that, when the sliding guide carrier 53 is in
its readiness position and the closure cap 4 in the closure
position, the sliding guide carrier 53, in addition to being
securely held in its readiness position by the thrust rod 43 of the
trigger device, is additionally secured in its readiness position
by the entrainment portions 64 of the closure cap 4 so that, even
for example when an inhaler 1 in the stressed condition is dropped,
the entrainment portions 64 of the closure cap 4, by way of the
second or complementary sliding guide portion 69, reliably prevent
delivery of a dose of the drug into the dosing passage. Desirably
the actuating or complementary sliding guide 67 is inclined through
an angle a of between 15.degree. and 45.degree. with respect to the
sliding guide 66 in the form of a guide means, in the housing 2.
For adaptation of the actuating forces to the travel-dependent
biasing force of the biasing spring 54, it may also be desirable if
the complementary or actuating sliding guide 67 extends in a
non-rectilinear configuration. As an alternative to the arrangement
involving entrainment portions 64 and the actuating or
complementary sliding guide 67, the closure cap 4 can also have a
pressure lever, by way of which a sliding guide carrier 53 can be
directly or indirectly moved into its readiness position. That is
appropriate in particular when, in comparison with the arrangement
described as the preferred one, the readiness position of the
sliding guide carrier 53 is disposed above the rest position. Such
an arrangement is diagrammatically shown in FIG. 35.
[0172] It may however also desirable for an eccentric disc to be
actuated by way of the entrainment portions 64 on the closure cap
4, in which case the rectilinear actuation of the closure cap is
converted into a rotary movement about the fixing axis of the
eccentric disc 70 and the sliding guide carrier 53 is moved by way
of the eccentric disc into its readiness position against the force
of the biasing spring 54. That is appropriate in particular in
conjunction with a biasing spring 54 in the form of a coil spring
or a torsion spring. Such an arrangement is diagrammatically shown
in FIG. 36.
[0173] In another particularly preferred embodiment of an inhaler 1
according to the invention the biasing of the dosing mechanism is
achieved by a purely rotational movement of the protective cap 4.
That embodiment can be particularly clearly seen in FIGS. 1, 2, 11,
17 and 18. In that respect FIGS. 1 and 17 show the inhaler 1 with
its closure cap 4 in its closure position. For the sake of clarity
the view in FIG. 17 omits the housing 2 and some further parts of
the inhaler 1. FIGS. 2 and 18 show the inhaler 1 with its closure
cap 4 in its operative position, that is to say with the protective
cap 4 open. For the sake of simplicity of the drawing the housing 2
and some further parts of the inhaler 1 are also omitted from FIG.
18. FIG. 17 shows the arrangement of the individual parts of the
inhaler 1 with the dosing mechanism in the released condition, that
is to say the biasing spring 54 (not shown in this Figure) is
relieved of stress and the drive element in the form of the drive
rocker 82 is in its rest position. FIG. 18 shows the arrangement of
the individual parts of the inhaler 1 with the dosing mechanism
stressed by opening of the closure cap 4, that is to say the
biasing spring 54 (not shown in this Figure) is stressed and the
drive element in the form of the drive rocker 82 is in its
readiness position. In that operative condition of the inhaler 1
inhalation can be effected by the patient at any time, by the
patient drawing in air through the mouthpiece and triggering a
dosing operation when a trigger airflow is exceeded, as described
hereinbefore.
[0174] The closure cap 4 has at least one entrainment portion 64
and a transmission rocker 85 which is operatively connected to the
drive rocker 82 pivotable about a first pivot axis 83, the
transmission rocker 85 being pivotable about a second pivot axis
84, while the closure cap is pivotable out of the closure position
into the operative position about the (third) axis 7. The at least
one entrainment portion 64 of the closure cap 4 engages behind at
least one operative end 86 of the transmission rocker 85 upon
opening of the closure cap 4 so that the drive rocker 82 is movable
by the movement of the closure cap 4 about the third axis 7 out of
the closure position into the operative position by way of the
transmission rocker 85 against the force of the biasing spring 54,
out of its rest position into its readiness position.
[0175] The drive rocker 82 and the transmission rocker 85 are in
engagement with each other in such a way that their rotation about
the first and second pivot axes 83 and 84 takes place in opposite
relationship. As a result the moments of inertia upon triggering of
drug delivery substantially cancel each other out so that the
patient is only slightly adversely affected by return forces which
are perceived as a knock and corresponding noise. Advantageously in
that respect the drive rocker 82 and the transmission rocker 85 are
of such a design configuration and dimensions that the moment of
inertia of the drive rocker 82 about the first pivot axis 83 and
the moment of inertia of the transmission rocker 85 about the
second pivot axis 84 are of approximately equal magnitude.
[0176] Advantageously the at least one operative end 86 of the
transmission rocker 85 is so designed that, upon actuation of the
closure cap 4 from the closure position into the operative position
about the third axis 7 the operative end 86 is engaged in
positively locking relationship by the at least one entrainment
portion 64 of the closure cap 4 and the moment applied by the at
least one entrainment portion 64 is transmitted to the transmission
rocker 85 if the dosing mechanism is not already prestressed. Upon
the return of the closure cap 4 from the operative position into
the closure position and of the transmission rocker 85 which is
returned to the rest position by triggering of a dosing operation,
the operative end 86 elastically evades the entrainment portion 64.
For that purpose the operative end 86 is connected to the rest of
the transmission rocker 85 by way of a film hinge 87 arranged at
the end more remote from the mouthpiece 5. In that way it is
possible for the closure cap to be moved into a protecting
condition over the mouthpiece again even when a drug dose has not
yet been taken.
[0177] Desirably the transmission rocker 85 is of a symmetrical
configuration relative to the longitudinal central plane of the
inhaler 1 and includes two rocker elements which are arranged on
both longitudinal sides of the inhalation device pivotably about
the second pivot axis 84 and are connected together with at least
one yoke 86, wherein the thrust rod 43 holds the transmission
rocker 85 in the prestressed position of the drive rocker 82 by
engagement with the yoke 88 when the flap 42 is in its rest
position and the thrust rod 43 clears the travel of the yoke 88 and
therewith the transmission rocker 85 when the flap 43 is deflected
out of its rest position at least by a predetermined amount so that
the transmission rocker 85 and the drive rocker 82 are movable from
their readiness position into their rest position by the biasing
spring 54.
[0178] As already mentioned hereinbefore an inhaler 1 according to
the invention includes a counting device 11 for accurate-dose
representation preferably of the number of doses which can still be
taken from the stored drug supply, by way of the display 10. For
that purpose the counting device 11 can advantageously be formed by
a known two-digit or three-digit drum counter. Such drum counters
can be inexpensively made from plastic material and can therefore
also be easily disposed of with the inhaler 1 after the expiry of
the working life thereof. In comparison with an electronic counter
which has already been proposed for such purposes, this has the
advantage that the inhaler 1 does not have to be broken up as an
expensive and complicated procedure after the expiry of its useful
fife so that electronic components can be sent separately for
specific processing and disposal in accordance with the prescribed
procedure. The drum counter can in the usual fashion be driven by
way of a stepping switching mechanism 37 by the sliding guide
carrier and is advanced by 1 with each stroke movement performed by
the sliding guide carrier 53, see FIG. 55. Advantageously in that
respect the arrangement is such that the counting device counts
downwards to represent the doses that still remain. The starting
value of the display 10 must therefore be set to a value
corresponding to the filling amount of doses of the drug in the
storage chamber 13 of the cartridge 3 less a safety value to take
account of fluctuations in the filling amount or possible settling
effects in the drug powder. After a predetermined number of doses
have been counted down, an index is displayed, for example in the
form of a coloured emphasis which indicates a consumed supply of
drug. A sequence of the last three actuations of such an inhaler is
depicted in FIG. 21, steps A, B and C.
[0179] Furthermore the preferred inhaler 1 according to the
invention is provided with a locking device which, upon the
attainment of a predetermined number of delivered doses, blocks the
closure cap 4 in such a way that the closure cap 4 is no longer
movable into the closure position. The locking device includes a
locking stirrup 71 which comprises two limbs 72 connected by a yoke
73. The yoke 73 of the locking stirrup 71 is pressed against the
drum counter by a spring 74, preferably a leaf or shaped spring,
see FIG. 12.
[0180] Desirably the drum counter is of such a design that each
drum has a groove 75 so that the grooves 75 of the drums are
aligned when a displayed counter state 000 is reached. The locking
stirrup 71 is arranged in such a way that the yoke 73 is engaged by
the spring 74 into the aligned grooves 75 of the drums and thus the
entire locking stirrup 71 is displaced by a distance. In that case
the ends of the limbs 72, which are not connected by the yoke 73,
engage into the path of movement of the entrainment portions 64 of
the closure cap 4 and/or into the sliding guide of the housing 2 so
that the entrainment portions 64 can no longer be displaced along
the sliding guide 66 and thus the closure cap 4 can no longer be
moved into the closure position. Desirably the engagement by the
limbs 72 of the locking stirrup 71 is so far removed from the
closure position of the closure cap 4 that the closure cap 4
projects from the housing 2 so markedly detectably (FIGS. 11, 54)
that even a less well-informed patient clearly perceives that and
knows that the stored supply of drug in that inhaler 1 is
consumed.
[0181] Finally, it is possible to mount to the yoke 73 of the
locking device 71 a signal plate 76 so that, upon blocking
engagement of the locking device 71 or upon engagement of the yoke
73 into the grooves 75, the signal plate 76 is pivoted in front of
the display 10. The signal plate 76 can carry a signal colour
and/or can be labelled with an item of text "EMPTY" or a similar
item of information which unmistakeably indicates to the patients
that the stored supply of drug in that inhaler 1 has been exhausted
and no further dose is to be obtained from that inhaler 1. Instead
of a drum counter it is also possible to use a strip running
mechanism as the display 10. Instead of the grooves 75, a hole can
be provided in the strip at a suitable location so that a pin or
the like on the yoke 73 can engage into the hole in the strip in
order to actuate the locking device 71 and the signal plate 76.
[0182] In the particularly preferred embodiment of an inhaler 1 as
shown in FIGS. 11 and 17 the locking device has a spring lever
blocking rod 81 which, upon the attainment of a predetermined
number of delivered doses, is movable from a rest position (FIGS.
17, 18) into a blocking position and which in its blocking position
engages in blocking relationship into the path of the closure cap 4
so that the closure cap 4 can no longer be moved into the closure
position (FIG. 11). That arrangement provides for both particularly
clear signalling and also prevents (futile) further use of the
inhalation device 1 and thus unwanted under-dosing. In that
arrangement the blocking rod 81 can be coupled in spring-loaded
relationship to the counting device 11, as described hereinbefore,
and is arrested in its blocking position for example by a locking
pawl (not shown) or a latching tooth so that the blocking rod 81
cannot be pushed back into its rest position against the force of
its actuating spring. That ensures that the blocking condition
cannot be undone without destroying component parts of the inhaler
1. In that case the blocking rod 81 can be designed with a signal
colour so that the blocked condition is more clearly
perceptible.
[0183] For the particular situation of use of an inhaler 1
according to the invention for emergency medicine the locking
element in the form of the locking stirrup 71 or the blocking rod
81 can be omitted in order to comply with corresponding
regulations. More specifically the view is sometimes taken that, in
this specific situation of use, the possible option of still being
able if necessary to inhale residual amounts from the storage
chamber 13, even if the nominal number of doses has already been
taken, should have priority over protection from under-dosing when
there is an insufficient stored supply of drug, such protection
being ensured by the blocking action.
[0184] The procedure involved in a usual process of using a
preferred embodiment of an inhaler 1 according to the invention is
shown in FIGS. 37 to 47. The illustrated embodiment and the view
represented correspond to the embodiment in FIGS. 1, 2, 11, 17 and
18. For the sake of better visibility of the different positions of
the components therefore the references from FIGS. 11, 17 and 18
have not been repeated here.
[0185] FIG. 37 shows the inhaler 1 with closed closure cap 4 and
with the dosing mechanism in the relieved condition, that is to say
the biasing spring 54 (not shown in this Figure) is relieved of
stress and the drive element in the form of the drive rocker 82 is
in its rest position.
[0186] FIG. 38 shows the inhaler 1 during a first phase of pivoting
the closure cap 4 open. In the pivotal movement of the closure cap
4 about the (third) pivot axis 7 entrainment portions 64 of the
closure cap 4 engage behind the operative end 86 of the
transmission rocker 85 and thereby pivot the transmission rocker 85
about the second pivot axis 84. The transmission rocker 85 engages
with entrainment portions 89 into an opening 90 in the drive rocker
82 and entrains it in the pivotal movement of the transmission
rocker 85 so that the drive rocker 82 is pivoted about the first
pivot axis 83 against the force of the biasing spring 54 (FIG. 56).
Arms 79 of the drive rocker 82 move relative to the entrainment
projections 51 of the dosing slider 15, which are in the form of a
ramp in the direction of movement of the dosing slider 15, so that
the arms 79 are spread open by the ramp. As soon as the arms 79
have passed the ramp of the entrainment projections 51 of the
dosing slider 15, they snap together again (FIG. 39) and can
subsequently entrain the dosing slider 15 in movement in the
opposite direction.
[0187] When the operative position of the closure cap 4 is reached
(see FIG. 18) the dosing mechanism is stressed and the transmission
rocker 85 and the drive rocker 82 are secured in the biased
readiness position by the thrust rod 43.
[0188] When now a patient sucks an airflow through the inhaler 1
the flap 42 is deflected out of its rest position (FIG. 40). In
that operative condition the dosing slider 15 is still in its
filling position and the cartridge 3 is sealed off with respect to
the ambient atmosphere.
[0189] When the predetermined minimum airflow in the air passage 39
is exceeded by the patient breathing in and thus the flap 42 is
deflected beyond the trigger threshold, as shown in FIG. 41, the
thrust rod 43 is pulled forward by the movement of the flap 42
beyond the trigger threshold to such an extent that it comes out of
engagement with the yoke 88 of the transmission rocker 85 and thus
the automatic movement of the dosing mechanism is enabled. Driven
by the force of the biased biasing spring 54 the drive rocker 82
and the transmission rocker 85 pivot back in the direction of the
rest position. In that case the arms 79 of the drive rocker 82 push
the dosing slider 15 out of its filling position into its emptying
position by way of the entrainment projections 51 of the dosing
slider 15 so that the drug powder is discharged out of the dosing
cavity 17 of the dosing slider 15 by means of the airflow produced
by the patient and finally discharged through the inhalation
opening 6 of the mouthpiece 5.
[0190] After the emptying position of the dosing slider 15 is
reached further pivotal movement of the drive rocker 82 and the
transmission rocker 85 provides that the arms 79 of the drive
rocker 82 come out of engagement with the entrainment projections
51 of the dosing slider 15 and the dosing slider 15 is pushed back
into its filling position by the force of the return spring 59 and
thus sealing integrity of the cartridge 3 is ensured again (FIGS.
42 and 43). Hermetic sealing integrity of the cartridge 3 and in
particular the storage chamber 13 is therefore interrupted only for
fractions of a second, namely the period of time required for the
dosing slider 15 to be conveyed out of the filling position into
the emptying position and back again. That period of time is only
determined by the configuration of the device and cannot be
influenced by the user.
[0191] The patient can now pivot the closure cap 4 back into the
closure position again (FIG. 44). In that case the entrainment
portions 64 of the closure cap 4 knock against the operative ends
86 of the transmission rocker 85 (FIG. 45). In that case the
operative ends 86 move away from the entrainment portions 64 by
virtue of pivoting by way of the film hinges 87 (FIG. 46) and
pivoting back into their starting position again after passing the
entrainment portions 64 (FIG. 47) as soon as the closure cap 4 is
closed so that it is engaged by the entrainment portions 64 again
in the next activation. That arrangement also ensures that the
closure cap 4 can be opened and closed again even when the dosing
mechanism is in a stressed condition with the transmission rocker
85 and the drive rocker 82 in the readiness position.
[0192] The embodiment of an inhalation device according to the
present invention shown in FIGS. 19-21, 28-31 and 48 to 55 is
particularly useful in a number of medical applications if the at
least one storage chamber 13 is provided by a cartridge holder
device 100 and a lid 101, wherein the lid 101 has a shape capable
of receiving the drug powder content of the storage chamber 13 in
an upside-down position of the inhalation device 1. That allows
pre-mounting of the cartridge holder 100 and the dosing slider 13
during manufacture of the inhalation device including testing. The
lid 101 may serve as an open-top cartridge and filled with the
appropriate amount of drug powder in the pharmaceutical
manufacturing line, and directly inserted into the inhalation
device 1 held upside down. So the inhalation device can be
delivered ready to use from the medicament manufacturer. The lid
101 is sealingly fixed onto the cartridge holder by snap connectors
102.
[0193] As can be seen from FIGS. 19-21, 28-31 and 48 to 55 the
cartridge holder device 100 comprises two storage chambers each
covered by a lid 101, wherein the cartridge holder device 100
comprises a twin dosing slider 15. This allows easy and accurate
dosing from two different drug reservoirs 13, for instance for the
combination of medicaments which may not be stored together to
avoid degradation. Further, with the embodiment shown in FIGS.
19-21, 28-31 and 48 to 55, the cartridge holder device 100
comprises two storage chambers 13 each covered by a lid 101,
wherein the cartridge holder device 100 comprises a twin dosing
slider 15.
[0194] In the inhalation device 1 the trigger device 43 has an
engagement portion 90 interacting with a stepped stop element 91 of
the drive element 53, 82, wherein the stepped stop element 91 has a
first step 97 and the drive element is arrested in an intermediate
position when the engagement portion 90 of the trigger device 43
interacts with the first step 97. In this state, dosing of the
medicament will take place. The stepped stop element 91 has a
second step 98 and the drive element 53, 82 is held in its rest
position when the engagement portion 90 of the trigger 43 device
interacts with the second step 98. In this state the closure cap 4
is closed, the drive element 53, 82 is in rest position and the
flap 42 closed, as shown in FIGS. 19 and 20.
[0195] When starting from the rest position of the drive element
53, 82 the closure cap 4 will be opened, the cap 4 rotates about
axis 84. The entrainment portion 94 of the cap 4 engages with the
sliding guide 93 formed at the bottom edge of the drive element 53,
82, thus, moving the drive element 53, 82 upwardly against the
force of biasing spring 54, as shown in FIGS. 28 and 29.
[0196] When the operative position of the closure cap 4 is reached
as shown in FIGS. 30 and 31, the dosing mechanism is tensioned and
the drive element 53 is secured by the engagement portion 90 of the
trigger device 43 interacting with projection 96 of the drive
element 53. The flap 42 is closed. In this position it is possible
to close and re-open the closure cap 4 without adverse effects. The
inhalation device is now ready for inhaling.
[0197] When a patient starts inhaling through the mouthpiece 5, the
flap 42 starts to pivot about a pivot axis 80 against the force of
spring 99 thereby retracting engagement portion 90 of the trigger
device 43 interacting with projection 96 of the drive element 53,
see FIGS. 48 and 49.
[0198] On release of the drive element 53 from engagement portion
90 of the trigger device 43 interacting with projection 96 drive
element 53 starts travelling downwards, thereby engaging
entrainment projections 51 of the dosing slider 15 for movement of
the dosing slider 15. Those entrainment projections 51 of the
dosing slider 15 co-operate with corresponding recesses of an
actuating device 53 for the dosing slider in the inhaler, see FIG.
50. So, the dosing slider 15 will be retracted from the dosing
slider channel 16 until the slider 15 reaches his emptying
position, FIG. 51. At the same time engagement portion 90 of the
trigger device 43 engages with the first step 97. As long as the
flap 42 keeps fully open due to inhaling, the drive element 53 is
arrested in an intermediate position when the engagement portion 90
of the trigger device 43 interacts with the first step 97, thus
keeping the dosing slider 15 in its emptying position, see FIG.
52.
[0199] Once the inhalation process is completed and the flap 42
returned to its initial position, second step 98 and the drive
element 53, 82 is held in its rest position when the engagement
portion 90 of the trigger 43 device interacts with the second step
98. In this state the closure cap 4 may be closed, and the cycle
completed, as shown in FIG. 53 compared to FIGS. 19 and 20 at the
beginning.
[0200] The counting device 11 is connected to the engagement
portion 90 of the trigger device 43 and the stepped stop element 91
of the drive element 53, 82 has an opening or recess 92, and the
drive element 53, 82 is urged by the biasing spring 54 to a
blocking position as shown in FIG. 54, when the engagement portion
90 engages with the opening or recess 92, once removal of a
predetermined number of doses has been removed from the inhalation
device 1, thus the storage chamber 13 is considered empty, and the
device should no longer be used.
[0201] While this invention has been described as having a
preferred design, the present invention can be further modified
within the spirit and scope of this disclosure. This application is
therefore intended to cover any variations, uses, or adaptations of
the invention using its general principles. Further, this
application is intended to cover such departures from the present
disclosure as come within known or customary practice in the art to
which this invention pertains and which fall within the limits of
the appended claims.
* * * * *