U.S. patent application number 10/526241 was filed with the patent office on 2006-06-08 for inhaler for powdery, in particular, medical substances.
Invention is credited to Alfred von Schuckmann.
Application Number | 20060118106 10/526241 |
Document ID | / |
Family ID | 32087917 |
Filed Date | 2006-06-08 |
United States Patent
Application |
20060118106 |
Kind Code |
A1 |
Schuckmann; Alfred von |
June 8, 2006 |
Inhaler for powdery, in particular, medical substances
Abstract
Inhaler (1) for powdery, in particular medical substances (10),
having a suction air channel (12) leading to the mouthpiece (3),
and a storage chamber (11) for a substance (10). A linearly moving
dosing chamber (26) apportions a specific amount of substance from
the storage chamber (11) into the region of a transfer point to a
suction air stream (S) of the air channel. A component of the
suction air stream (S), that lies in the direction in which the
dosing chamber (26) extends, empties the dosing chamber (26).
Inventors: |
Schuckmann; Alfred von;
(Kevelaer, DE) |
Correspondence
Address: |
Martin A Farber
Suite 473
866 United Nations Plaza
New York
NY
10017
US
|
Family ID: |
32087917 |
Appl. No.: |
10/526241 |
Filed: |
September 16, 2002 |
PCT Filed: |
September 16, 2002 |
PCT NO: |
PCT/EP02/10353 |
371 Date: |
November 21, 2005 |
Current U.S.
Class: |
128/200.14 ;
128/200.12 |
Current CPC
Class: |
A61M 15/0006 20140204;
A61M 15/0065 20130101; A61M 2202/064 20130101 |
Class at
Publication: |
128/200.14 ;
128/200.12 |
International
Class: |
A61M 15/00 20060101
A61M015/00; A61M 11/00 20060101 A61M011/00 |
Claims
1-27. (canceled)
28. Inhaler (1) for powdery, in particular medical substances (10),
comprising: a mouthpiece (3) and a suction air channel (12) leading
to the mouthpiece (3), a storage chamber (11) for the substance
(10) and a linearly moving dosing chamber (26) for apportioning a
specific amount of substance from the storage chamber (11) into a
region of a transfer point (U) to a suction air stream (S) within
the air channel (12); wherein a component of the suction air stream
(S) that lies in the direction in which the dosing chamber (26)
extends empties the dosing chamber (26).
29. Inhaler according to claim 28, further comprising a spindle
(25), and wherein the dosing chamber (26) is disposed in the
spindle (25) and is configured as a transverse bore of the spindle
(25), which chamber (26) can be displaced by the spindle (25) in
dependence on a closure cap of the inhaler.
30. Inhaler according to claim 29, wherein the transverse bore is
conical.
31. Inhaler according to claim 29, further comprising an air
passage (40) adjoining the suction air stream (S), the air passage
(40) being associated with the dosing chamber (26).
32. Inhaler according to claim 31, wherein the air passage (40) is
respectively provided upstream of each of two openings of the
dosing chamber (26).
33. Inhaler according to claim 29, wherein the transverse bore has
a portion of larger diameter and a portion of smaller diameter, and
that associated with a larger clear diameter end of the dosing
chamber (26) is an air passage (40) of a smaller diameter than it
and associated with a smaller clear diameter end is an air passage
(40) of a larger diameter than it.
34. Inhaler according to claim 33, wherein the air passages (40)
are formed on a cup-shaped rotary part (22) guiding the spindle
(25) and are in flow communication with air inlets (42) in the
lateral wall (37) of the mouthpiece (3).
35. Inhaler according to claim 33, wherein the air passages (40)
are disposed axially offset in relation to the air inlets (42)
lying closer to the mouthpiece (3).
36. Inhaler according to claim 34, wherein the rotary part (22)
forms with its cup base the top (23) of the storage chamber (11),
the center of which has a guiding opening (24) for the spindle (25)
acting as a plunger slide.
37. Inhaler according to claim 34, wherein the spindle (25), which
is pointed at the end in the plunging direction in the manner of a
screwdriver blade, is rotationally connected to the rotary part
(22) by means of radial fins (33).
38. Inhaler according to claim 37, wherein a cup wall (35) of the
cup-shaped rotary part (22) has axial guiding slots (34) in which
the fins (33) are guided.
39. Inhaler according to claim 29, further comprising an extension
limiting stop (36) of the spindle (25) that is provided by the
mouthpiece (3), defining the ready-to-empty position of the dosing
chamber (26), which with its base wall portion provides the
transfer point (U).
40. Inhaler according to claim 29, further comprising a docking
point (28) between the spindle (25) and a closure cap (4) that lies
on the mouthpiece side and disengages if overloaded.
41. Inhaler according to claim 34, wherein the rotary part (22) has
a rotor (R) with which a stator (St) is associated, with a scooping
effect acting so as to carry substance into the dosing chamber (26)
when the rotary part (22) is reversed in its rotation.
42. Inhaler according to claim 34, further comprising web-carried
rotor blades (47) extending from an annular disk (49) of the base
of the rotary part (22).
43. Inhaler according to claim 42, wherein the rotor blades (47)
have a sickle-shaped outline.
44. Inhaler according to claim 42, wherein there are two of the
rotor blades (47) lying opposite each other.
45. Inhaler according to claim 42, wherein the rotor blades (47)
extend substantially on a quarter sector, with a flank (50)
directed radially toward the center of the spindle (25) and a blade
flank (51) lying approximately at right angles thereto in
tangential alignment with the spindle (25) in such a way as to
leave a gap.
46. Inhaler according to claim 45, wherein the flanks (50) lie in a
common diametral line (y-y).
47. Inhaler according to claim 41, wherein the rotor (R) engages
under the stator (St) in such a way that the stator (St) is formed
as a projection protruding radially inward from an inside wall of
the storage chamber (11) and extending freely into a rotational
path (54) of the rotor (R).
48. Inhaler according to claim 47, wherein the stator (St) has a
trapezoidal outline with a base in the inside wall of the storage
chamber (11).
49. Inhaler according to claim 47, wherein the rotational path (54)
is axially limited by the underside of an annular disk (49) of the
rotary part (22) and an inner side of the rotor blades (47) facing
it.
50. Inhaler according to claim 49, wherein the stator (St) lies in
outline beneath the quarter sector, leaving an interspace (55)
between two rotor blades (47).
51. Inhaler according to claim 36, wherein the guiding opening (24)
within the rotary part (22) is lined by a sealing bush (56)
enclosing the cylindrical portion of the spindle (25).
52. Inhaler according to claim 34, further comprising a sealing
ring (58) inserted with preloading between an inside wall of the
storage chamber (11) and a rotary part (22).
53. Inhaler according to claim 52, wherein the sealing ring (58) is
snap-fitted in annular grooves (59, 60) of both parts, the annular
groove (59) located on the rotary part (22) taking the form of a
V-shaped notched groove and the annular groove (60) of the storage
chamber (11), lying at the same height as said notched groove,
being of a semicircular form.
54. Inhaler according to claim 28, further comprising a closure cap
(4) that is formed as a screw cap and interacts with the mouthpiece
(3) via co-rotating means (45/46).
Description
[0001] The invention relates to an inhaler for powdery, in
particular medical substances, with a suction air channel leading
to a mouthpiece, also a storage chamber for the substance and a
linearly moving dosing chamber for apportioning a specific amount
of substance from the storage chamber into the region of a transfer
point to the suction air stream.
[0002] An inhaler of this type is known from DE-A 40 27 391. The
amount of substance to be discharged is transferred in a downwardly
tapering storage chamber to the dosing chamber, which is capable of
moving out. The delivery means is a linearly movable slide
comprising said dosing chamber. Placed into the channel of the
mouthpiece, a rearward space of the dosing chamber docks onto a
volume of air stored in a piston/cylinder unit. When the inhalation
takes place in the sense of a suction air stream, the volume of air
is abruptly set free and released. The suction stroke, mechanically
flow-assisted in this way, clears the dosing chamber in an emptying
manner. The expulsion of compressed air triggered by the reduced
pressure requires considerable structural complexity; for most
patients, it also takes some time and effort to get used to the
suddenly occurring surge of air.
[0003] An object of the invention is to form an inhaler of the
generic type in a structurally simple way, such that there is no
longer any need to provide an external air stream but nevertheless
a complete discharge of a reproducible portion is obtained.
[0004] This object is achieved first and foremost in the case of an
inhaler with the features of claim 1, it being provided that a
component of the suction air stream lying in the direction in which
the dosing chamber extends empties the dosing chamber.
[0005] As a result of such a configuration, a structurally simple,
functionally reliable inhaler is achieved. The inhalation produces
a reduced pressure for discharge that is adequate for the dosing
chamber to be emptied satisfactorily. The region where the dose is
administered lies close to the flow component, in a manner which is
extremely effective for the discharge. The linearly moving dosing
chamber operates with a drawing effect and, on reaching the
transfer point, is so detached from the storage region of the
powdery substance that it is no longer possible for any substance
to fall back. The prior art attempts to prevent this possible
source of unequally apportioned amounts by the use of a screen with
respect to the rearward space, that is with respect to the incoming
external air stream.
[0006] The subject matters of the further claims are explained
below with reference to the subject matter of claim 1, but may also
be of importance in their independent formulation. For instance, it
is further proposed that the dosing chamber is configured as a
transverse bore of a spindle which can be displaced in dependence
on a closure cap. In this way, the ready-to-discharge position is
as it were automatically brought about, simply by the customary
handling of closing and opening taking place. The preferably
continuous transverse bore can be cleared out from two sides. A
particularly effective measure is obtained by a conical transverse
bore. The apportioned amount of substance is transferred even more
quickly via the component of the suction air stream from the
widening end. To achieve conducting of the air of the component in
the direction in which the dosing chamber extends, it is of
significance that an air passage adjoining the suction air stream
is associated with the dosing chamber. This produces as it were a
localized zone of reduced pressure. It is advantageous for an air
passage to be respectively provided upstream of each of the two
openings of the dosing chamber. In the case of the conical
transverse bore, it is suitable also to provide that associated
with the larger clear diameter end of the dosing chamber is an air
passage of a smaller diameter than it and associated with the
smaller clear diameter end is an air passage of a larger diameter
than it. As a result of greater reduced pressure, substance is
therefore cleared predominantly from the widening side, that is
specifically in the direction in which there is no frictional
hindrance as a result of the correspondingly widening walls of the
dosing chamber. The invention then proposes that the air passages
are formed on a cup-shaped rotary part guiding the spindle and are
in flow communication with air inlets in the lateral wall of a
mouthpiece. The corresponding air inlets are disposed on the
lateral wall of the inhaler in such a way that they cannot be kept
closed either by the user's lips or by the gripping hand holding
the stick-shaped body of the inhaler. The risk of them being kept
closed is minimized moreover by a number of air inlets that are
spaced apart from one another being formed. For the purpose of good
distribution of the powdery substance in the suction air stream, it
is also provided that the air passages are disposed axially offset
in relation to the air inlets lying closer to the mouthpiece. This
produces an initially contra-acting flow path. Furthermore, it
proves to be advantageous for the rotary part to form with its cup
base the top of the storage chamber, the center of which has a
guiding opening for the spindle acting as a plunger slide. In this
way, the cup base is given a dual function: indirect or direct
cover and guiding hole for the spindle. Another advantageous
feature is for the spindle, which is pointed at the end in the
plunging direction in the manner of a screwdriver blade, to be
rotationally connected to the rotary part by means of radial fins.
On the one hand, the knife-like blade achieved in this way not only
brings about an effective rotationally loosening action in the
central region but at the same time also helps the spindle to
plunge into the mass of powder, and on the other hand it provides
welcome support for the spindle with respect to the rotary part,
and what is more makes it possible for the alignment of the air
passages with the dosing chamber to be retained. The necessary
relative linear movement of the spindle and the rotary part in
relation to each other is achieved by simple means, in that the cup
wall of the cup-shaped rotary part has axial guiding slots in which
the fins are guided. This solution is further characterized by an
extension limiting stop of the spindle that is provided by the
mouthpiece, defining the ready-to-empty position of the dosing
chamber, which with its base wall portion provides the transfer
point. The closure-cap dependent mounting of the spindle is further
characterized by a docking point between the spindle and the
closure cap that lies on the mouthpiece side and disengages if
overloaded. When the inhaler is closed again, renewed docking
between the spindle and the closure cap is conversely obtained. A
configuration that is even of independent significance is then
embodied by the fact that the rotary part has a rotor with which a
stator is associated, with a scooping effect acting so as to carry
substance into the dosing chamber when the rotary part is reversed
in its rotation. By this means, the replenishment and density of
the amount of powder in the dosing chamber can be kept consistent.
In addition to this there is a loosening effect in the surrounding
area, which rules out the chance of parts of the powder becoming
clogged. Reversed rotation means unscrewing of the closure cap and
the accompanying charging action of the, or on the, dosing chamber.
To be specific, the scoop assembly is formed by web-carried rotor
blades extending from an annular disk of the base of the rotary
part. Said blades have a lancet- or sickle-shaped outline. Two
rotor blades lying diametrically opposite each other are realized.
As far as the actual structure is concerned, it is also provided
that the rotor blades extend substantially on a quarter sector,
with a flank directed radially toward the center of the spindle and
a blade flank lying approximately at right angles thereto in
tangential alignment with the spindle in such a way as to leave a
gap. This rules out points of excessive compression. The medical
substance adhering for example to a carrier is not rubbed off from
it. It is then provided that the flanks lie in a common diametral
line. The further structural features are also conducive to the
scooping action but do not adversely effect the medicament, in that
the rotor engages under the stator in such a way that the stator is
formed as a projection protruding radially inward from the inside
wall of the storage chamber and extending freely into a rotational
path of the rotor. The stator has a trapezoidal outline and is
rooted with its base in the inside wall of the storage chamber. The
rotational path is axially limited by the underside of the annular
disk of the rotary part and the inner side of the rotor blades
facing it. Furthermore, a configuration that is advantageous in
terms of the association between parts consists in that the stator
lies in outline beneath the quarter sector, leaving an interspace
between two rotor blades. This produces an adequately large
mounting opening. It is advantageous both in terms of sealing and
in terms of guidance if the guiding opening within the rotary part
is lined by a sealing bush enclosing the cylindrical portion of the
spindle. It may comprise rubber or rubber-like material. Powdery
substance deposited on the stem of the spindle is wiped off by the
sealing bush. There is no falsification of the dose ready to be
discharged. A likewise sealing-related measure of the dispenser
mechanism is obtained by a sealing ring inserted with preloading
between the inside wall of the storage chamber and the rotary part.
Here, too, rubber or rubber-like material may be used. It is then
provided that the sealing ring is snap-fitted in annular grooves of
both parts, the annular groove located on the rotary part taking
the form of a V-shaped notched groove and the annular groove of the
storage chamber, lying at the same height as said notched groove,
being of a semicircular form. The said notched groove is involved
in the rotational guidance of the rotary part. Finally, it is
proposed that the closure cap is formed as a screw cap and
interacts with the mouthpiece via co-rotating means. The latter are
similar to a claw coupling and disengage when there is a separation
of the threads.
[0007] The subject matter of the invention is explained in more
detail below on the basis of an exemplary embodiment illustrated in
the drawing, in which:
[0008] FIG. 1 shows the inhaler according to the invention in a
vertical section, enlarged, in the basic position with the cap
closed,
[0009] FIG. 2 shows the plan view of this,
[0010] FIG. 3 shows the inhaler in side view,
[0011] FIG. 4 shows the inhaler in section, as in FIG. 1, but with
the closure cap removed and therefore embodying the ready-to-remove
position,
[0012] FIG. 5 shows an enlargement taken from FIG. 1 with the
spindle in an intermediate position, the dosing chamber extending
at the height of the stator,
[0013] FIG. 6 shows the section along the line VI-VI in FIG. 5,
[0014] FIG. 7 shows a detailed representation of the rotary part
with the rotor and the stator in a perspective view from below,
showing the knife-like shape of the lower end of the spindle,
and
[0015] FIG. 8 shows an exploded drawing of the parts forming the
inhaler, to be precise in vertical section with respect all the
parts, in partial section with regard to the spindle.
[0016] The inhaler 1 represented in the drawing is realized as a
conveniently portable pocket device in the form of a short stick. A
stepped, cylindrical housing 2 determines its shape.
[0017] The cylindrical housing 2, which is like a small tube,
passes at the top end of the inhaler 1 into an attached mouthpiece
3. This is flattened appropriately for a mouth and can be
protectively engaged over by means of a cup-shaped closure cap
4.
[0018] The closure cap 4 is realized as a screw cap. An internal
thread 5 associated with it engages in a corresponding external
thread 6 on the lateral wall of the housing 2. In the region where
the mouthpiece 3 is attached, a clip 7 is integrally formed on the
closure cap 4.
[0019] At the bottom end, the end edge of the cup-shaped closure
cap 4 butts against an annular shoulder 8 with a stop-limiting and
sealing effect, achieved on account of the aforementioned step of
the cylindrical housing 2.
[0020] Using the axial screw stroke of the engagement of the
threads 5/6, the closure cap 4 acts at the same time as an
actuating handle 9 for delivering a powdery substance 10 in
reproducible portions 10', which substance is accommodated in a
storage chamber 11 of the housing 2 in an optionally refillable
manner. The dosing device, respectively transporting the portion
10' to a transfer point U lying outside the storage chamber 11, is
designated as a whole by D.
[0021] With respect to the material that can be dosed, it is a
medical, powdery substance 10, for example of the nature that basic
substances (lactose) capable of being transported by suction stream
act as a vehicle for carrying the micronized fine particles of
medicament sticking to their surface.
[0022] Provided downstream of the dosing device D is a so-called
dispersing region, in which the user produces a suction air stream
S which completely carries away the exactly apportioned amount 10'
of the substance 10 at the transfer point U. The suction air
channel leading to the mouthpiece 3 has the reference numeral
12.
[0023] The lower termination of the storage chamber 11 is formed by
a cup-shaped pressure-exerting base 13. This is under spring
loading in the direction of the mouthpiece 3. The corresponding
compression spring has the reference numeral 14. It is supported by
the bottom end winding on a base cap 15 closing the housing 2
there. Said base cap is in latching engagement with the portion of
the housing 2 of larger cross-section there. The corresponding
latching collar 16 engages in a matching annular groove of the
housing 2.
[0024] The top end winding of the biased compression spring 14
loads an inner shoulder 17 of a hollow piston 18 of the
piston-shaped device 13/18.
[0025] The stepped cup-shaped pressure-exerting base 13 is
connected in a latching manner to the inner shoulder 17.
[0026] The cup edge of the pressure-exerting base 13 provides an
annular lip 19, which on account of its rubber-elastic material
wipes off the wall of the storage chamber 21 without any substance
being lost.
[0027] Then a central standing spigot 20 extends from the base cap
15. Said standing spigot is hollow and, together with the hollow
piston 18, forms a spring chamber 21 for the compression spring
14.
[0028] At the mouthpiece end, the storage chamber 11 terminates
with a cup-shaped rotary part 22. This forms by its cup base the
top 23 of the storage chamber 11 engaging over the housing 2.
[0029] A guiding opening 24 is left at the center of the top 23.
This indirectly or directly formed guiding opening 24 receives a
spindle 25, as the key component of the dosing device D. As a
result of being appropriately configured, said spindle acts as a
linearly moving dosing chamber 26 for the portion 10' to be lifted
out, representing a plunger slide. It moves in the longitudinal
center axis x-x of the substantially rotationally symmetrically
configured inhaler 1.
[0030] At its end remote from the mouthpiece 3, the spindle 25
forms a point similar to a screwdriver blade. On account of the
co-rotation of the spindle 25, this has a loosening effect on the
central region with respect to the mass of powdery substance 10.
The blade 27, virtually resembling a pointed roof, has two
mirror-symmetrical oblique flanks and, at the base, adjoins the
cylindrical stem of the spindle 25. The oblique flanks enclose an
angle of about 60.degree.. The cylindrical base cross-section of
the spindle 25 is retained in the region of the blade 27 (see FIG.
7) The stroke of the linearly moving dosing chamber 26 makes
allowance in both end positions of the spindle 25 for the
cross-section of the guiding opening 24 to be kept closed with a
doctor-blade or wiping-off effect, filling the dosing chamber, over
the length of said opening 24.
[0031] The end of the closure 4 toward the mouthpiece forms a
docking point 28 between the spindle 25 and the closure cap 4. The
latching means on the closure cap is in this case a ring of hooks
capable of resilient deflection. Inwardly directed lugs 29 of the
resilient tongues of the ring of hooks engage in a narrow
waist-like annular groove 30 of the stem 25. In the outward
direction, the annular groove 30 continues into a latching head 31.
This can be overcome in both directions by the lugs 29. The
accumulation of material forming the latching head is approximately
lenticular.
[0032] The lugs 29, or their resilient tongues, are realized on a
small tube 32 which protrudes into the mouthpiece opening 3' and
extends from the inner side of the top of the closure 4. It is
rooted therein.
[0033] The stem 25 is rotationally connected to the rotary part 22
by means of radial fins 33 formed in the manner of spokes. The fins
33 engage with their free end portions, crossing the suction air
channel 12, in axial guiding slots 34--three are already
sufficient--of the rotary part 22. The guiding slots 34,
distributed at equal angles, are located on the inside of the cup
wall 35 of the cup-shaped rotary part 22. The axial guiding slots
34 are, moreover, of such a length that the powder-drawing plunging
stroke of the stem 25 out f a filling plane in the storage chamber
11 to the described transfer point U above the top 23 is
ensured.
[0034] The defined ready-to-empty position of the dosing chamber 26
is obtained by an extension limiting stop of the spindle 25 that is
provided by the mouthpiece 3. That is the extreme end of a
turned-back wall of the mouthpiece 3, which in this way keeps the
outlet of the guiding slots 34 closed.
[0035] The mouthpiece 3 acts via a lateral wall 37 in an anchoring
manner on the neck of the housing 2. There, a latching point 38 is
formed between the two parts 2, 3. It may be an irreversible
latching point 38. Moreover, as can be gathered, the top 23 of the
rotary part 22 is engaged over in a supported manner by an annular
shoulder 39.
[0036] The dosing chamber 26 is realized as a transverse bore
running substantially perpendicularly in relation to the
longitudinal center axis x-x. Transferred into the ready-to-empty
position, the dosing chamber 26 is in the effective region of the
central suction air stream S. An air passage 40 adjoining the
suction air channel 12 is associated with the dosing chamber 26.
Said air passage is formed in the cup wall 35 of the rotary part
22. It comprises radial bores. They extend in the vicinity of the
base of the cup-shaped rotary part 22, that is at the height of, or
just above, the upper side of the top 23.
[0037] It can be gathered that such an air passage 40 is provided
upstream and at a radial spacing from both open ends of the dosing
chamber 26. One precaution in this connection is that associated
with the larger clear diameter end of the dosing chamber 26 formed
by a conical transverse bore is an air passage 40 of a smaller
diameter than it and associated with the smaller clear diameter end
of the dosing chamber 26 is an air passage 40 of a larger diameter
than it. This produces a greater reduced pressure with a
predominant discharging effect with respect to the administered
portion 10' downstream of the air passage 40 of smaller diameter.
Nevertheless, the discharge, i.e. emptying of the dosing chamber
26, takes place from both ends.
[0038] The passages 40 formed on the cup-shaped rotary part 22,
guiding the stem 25 in a sealed manner, are also in flow
communication via a rearward annular space 41 with air inlets 42
which are at a radial distance. These air inlets 42 are also
configured as bores and provide the connection to the atmosphere.
Said annular space 41 is located between the outer side of the cup
wall 35 of the cup-shaped rotary part 22 and the inner side of the
lateral wall 37 of the mouthpiece 3.
[0039] It can be gathered that the air passages 40 are disposed
axially offset in relation to the air inlets 42. The air inlets 42
lie closer to the mouthpiece 3. The described spatial distancing
leads to an initially contra-acting inflow of sucked-in air
following on from the main suction air stream S. This and the fact
that a component of the suction air stream S lying in the direction
in which the dosing chamber 26 extends is built up has the effect
that the dosing chamber 26 is completely emptied. The user inhales
a precise dose each time. The transfer point U is provided here by
the base portion of the dosing chamber 26.
[0040] Conducive to the corresponding emptying is the special way
developed here of keeping the powder substance 10 ready in the
drawing region: this is so because conditions are created here to
ensure the aimed-for isostructural or homogeneous "packing" of the
dosing chamber 26, fed from a surrounding area where the substance
has been loosened. The rotary part 22 is used in particular for
this purpose, by way of a development. It has a rotor R acting in
the upper region of the storage chamber 11. A stator St is
associated with said rotor. Using the rotation of the rotary part
22, not only is a loosening effect obtained but at the same time
also a scooping effect acting so as to carry powder into the dosing
chamber 26 when the rotary part 22 is reversed in its rotation,
i.e. when the closure cap 4 is unscrewed, using the same as an
actuating handle 9. The corresponding entrainment is also obtained
with respect to the spindle 25, which is rotationally secured
radially by means of the fins 33, so that there is no displacement
of the axis of the dosing chamber 26 in relation to the air
passages 40. Even the lateral wall 37 could be included in the
rotational fixing by connecting means with positive engagement.
Generally, even co-rotation with frictional engagement is
sufficient, for example by means of the annular collar 43 keeping
the annular space 41 closed toward the mouthpiece end. Said annular
collar extends from the lateral wall of the cup wall 35 and lies
with its outer edge against the inner side of the lateral wall 37
of the mouthpiece 3.
[0041] As FIGS. 1 and 4 reveal, the co-rotation between the
mouthpiece 3 and the closure cap 4, lifting off by an unscrewing
action, takes place by a claw coupling 44 between the two. This
comprises a longitudinal toothing 45 on the lateral wall 37 of the
mouthpiece 3, which longitudinal toothing engages in corresponding
tooth gaps 46 on the inner side of the closure cap 43.
[0042] The scoop is formed by two rotor blades 47. These have a
basically sickle-shaped outline. The two rotor blades 47 are
located diametrically opposite with respect to the longitudinal
center axis x-x of the inhaler 1. They are mounted on axially
running webs 48 spaced at a distance from the center. The webs are
rooted in the underside of an arm or an annular disk 49 of the
rotary part 22 providing the rotor R.
[0043] The freely extending rotor blades 47 protruding from he base
or the top 23 of the rotary part 22 on the storage chamber side are
positioned diametrically opposite in such a way that they are
sufficiently spaced apart in the circumferential direction.
Geometrically, they substantially take up a quarter sector of the
circular cross-section of the storage chamber 11. Reference should
be made to FIG. 6. The two rotor blades 47 each have a flank 50
aligned radially with the center of the spindle 25 and each have a
scoop flank 51 lying at right angles thereto. It runs at a distance
from the lateral wall of the spindle 25 in such a way as to leave a
gap. The gap has the symbol 52. In this way, an abrasive effect is
avoided. It can be gathered that the flanks 50 are diametral. The
common diametral line of the flanks 50 is designated in FIG. 6 by
y-y. The spatially parallel scoop flanks 51 extend perpendicularly
in relation to the diametral line y-y and spatially parallel to the
axis z-z of the transverse bore of the dosing chamber 26, which in
turn coincides with the axis of the bore of the air passages
40.
[0044] The annular disk 49 or two arms in which the rotor blades 47
are rooted continues via an annular wall 53 into the top 23 of the
rotary part 22.
[0045] FIG. 5 illustrates particularly clearly that the rotor R
engages underneath the stator St in such a way that the stator St
is formed as a projection protruding radially inward from the
inside wall of the storage chamber 11 and extending freely into a
rotational path 54 of the rotor R. It can be gathered that the
rotational path 54 is axially limited by the underside of the
annular disk 49 of the rotary part 22 and the inner side of the
rotor blades 47 facing it. The axial distance forming the
rotational path is significantly greater than the thickness of the
stator St, that is the projection, measured in this direction.
Therefore, mechanical loads with respect to the frictionally
sensitive powdery substance 10 to be discharged do not occur here
either.
[0046] The stator St has a trapezoidal outline. Its arcuate base is
rooted in the inside wall of the storage chamber 11. The base is
dimensioned such that the stator St narrowing radially inward in
its surface area lies in outline beneath the quarter sector,
leaving an interspace 55 between two rotor blades 47. As FIG. 6
reveals, this at the same time provides an adequate mounting
opening for the stator to engage in the rotational path 54.
[0047] The radial projection of the stator St in the inward
direction is of such a radial length that the plateau of the
trapezoid ends before the outer side of the web 48, likewise
forming a gap.
[0048] The scooping effect is clear from FIG. 6 if the arrows are
observed. Arrow a indicates the direction of reversed rotation of
the rotary part 22. The scoop flanks 51 therefore act as a face
pushing the powder lying in front of it. Arrow b shows the
approaching scooping-in direction with respect to the end of the
dosing chamber 26 having the larger clear diameter. Arrow c
indicates the corresponding action at the other rotor blade 47,
that is here also with respect to the scooping action of the scoop
flank 51. The stator St then stands as it were as a fixed chicane
in the way of the rotational path 54. The powdery substance 10 is
displaced with a rapidly chamber-filling effect by the scoop flank
51 lying closer to the directing-in flank of the trapezoid, so
that, as already stated, consistent filling conditions always
occur. The dosing chamber 26 moves in an ascending manner through
the zone of the dosing device D in a number of rotations until it
has reached with its transfer point U the upper side of the top 23
of the cup-shaped rotary part 22.
[0049] There is also no entrainment of powder material that may be
adhering to the lateral surface of the spindle, as a result of the
guiding opening 24 with a wiping-off effect. Said opening is not
formed directly by the rotary part 22, but by a sealing bush 56
lining this passage. Said sealing bush consists of rubber-elastic
material and is held by being clipped into the top 23 by latching
means 57. In terms of its plane, it reaches at the top up to the
height of the upper side of the annular disk 49.
[0050] However, there is also no radially outer escape hole for
powder losses, since there is likewise a sealing element between
the rotary part 22 and the housing 2 forming the storage chamber
11. This is achieved by a sealing ring 58 of rubber-elastic
material inserted between the inside wall of the storage chamber 11
and the rotary part 22. Said sealing ring 58 is inserted under
preloading. The sealing ring 58 is snap-fitted in annular grooves
of both parts 2, 22. The annular groove located on the annular part
22 has the reference numeral 59. It is realized as a V-shaped
notched groove. The opening angle of the annular groove 59 lying in
the region of the annular wall 53 is about 90.degree.. The groove
contour has a centering and rotationally guiding effect. The other
annular groove 60, lying at the same height, is located on the
inner side of the housing 2, to be precise in the upper inlet
region of the storage chamber 11. Here there is a semicircular
shape with respect to the cross-section of the peripheral annular
groove 60. Mounting is made easier by a rotationally symmetrical
run-up slope 61 provided in front of the annular groove 60.
[0051] The spindle 25, formed as a lifting spindle, can be varied
with respect to the volume of its dosing chamber 26, i.e. the key
component of the dosing device D merely has to be exchanged to
achieve a different, precisely reproducible dosing of portions
10'.
[0052] The pressure-exerting base 13, acting in the manner of a
piston, is not impaired in its ability to move with respect to the
cylinder space, provided by the central portion of the housing 2,
since there the housing has an air-equalizing opening 62 lying to
the rear of the annular lip 19.
[0053] The cup-shaped pressure-exerting base 13 has a central
indentation, directed away from the storage chamber 11. It is of
such a depth on the inside that the end portion of the spindle 25
projecting axially downward beyond the rotor blades 47 in the basic
position is accommodated in it.
[0054] All features disclosed are (in themselves) pertinent to the
invention. The disclosure content of the associated/attached
priority documents (copy of the prior patent application) is also
hereby incorporated in full in the disclosure of the application,
including for the purpose of incorporating features of these
documents in claims of the present application.
* * * * *