U.S. patent application number 09/840875 was filed with the patent office on 2001-08-16 for inhalation device.
This patent application is currently assigned to AstraZeneca AB. Invention is credited to Burns, Stephen.
Application Number | 20010013342 09/840875 |
Document ID | / |
Family ID | 20411958 |
Filed Date | 2001-08-16 |
United States Patent
Application |
20010013342 |
Kind Code |
A1 |
Burns, Stephen |
August 16, 2001 |
Inhalation device
Abstract
An actuator for a pressurized metered dose inhaler, including: a
tubular section (38) providing an outlet through which medicament
is in use inhaled; and a nozzle block (42) including a tubular
element (44) having a free end over which the valve stem (14) of a
canister (2) is in use located and a spray orifice (50) in fluid
communication with the tubular element (44) for directing a spray
into the tubular section (38).
Inventors: |
Burns, Stephen; (Derby,
GB) |
Correspondence
Address: |
Nixon & Vanderhye P.C.
8th Floor
1100 North Glebe Rd.
Arlington
VA
22201
US
|
Assignee: |
AstraZeneca AB
|
Family ID: |
20411958 |
Appl. No.: |
09/840875 |
Filed: |
April 25, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
09840875 |
Apr 25, 2001 |
|
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|
09380294 |
Aug 31, 1999 |
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Current U.S.
Class: |
128/200.23 |
Current CPC
Class: |
A61M 15/009
20130101 |
Class at
Publication: |
128/200.23 |
International
Class: |
A61M 011/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 3, 1998 |
SE |
9802398-9 |
Jul 1, 1999 |
SE |
PCT/SE99/01198 |
Claims
1. An actuator for a pressurised metered dose inhaler, including: a
tubular section (38) providing an outlet through which medicament
is in use inhaled; and a nozzle block (42) including a tubular
element (44) having a free end over which the valve stem (14) of a
canister (2) is in use located and a spray orifice (50) in fluid
communication with the tubular element (44) for directing a spray
into the tubular section (38).
2. The actuator of claim 1, wherein the tubular element (44) is
configured such that an outer radial surface thereof is a close fit
with an inner radial surface of the valve stem (14) of the canister
(2).
3. The actuator of claim 2, wherein the tubular element (44) is
configured such that an outer radial surface thereof is a tight fit
with an inner radial surface of the valve stem (14) of the canister
(2).
4. The actuator of any of claims 1 to 3, wherein the tubular
element (44) is of circular section.
5. The actuator of any of claims 1 to 4, wherein the nozzle block
(42) includes an abutment against which in use bears the distal end
of the valve stem (14) of the canister (2).
6. The actuator of claim 5, wherein the abutment comprises a
surface (49) which extends radially outwardly of the tubular
element (44).
7. The actuator of any of claims 1 to 6, wherein the nozzle block
(42) includes a further tubular element (46) co-axial with the
first-mentioned tubular element (44) such that the tubular elements
(44, 46) define an annular channel (48) in which the valve stem
(14) of the canister (2) is in use located.
8. The actuator of claim 7, wherein the further tubular element
(46) is configured such that an inner radial surface thereof is a
close fit with an outer radial surface of the valve stem (14) of
the canister (2).
9. The actuator of claim 8, wherein the further tubular element
(46) is configured such that an inner radial surface thereof is a
tight fit with an outer radial surface of the valve stem (14) of
the canister (2).
10. The actuator of any of claims 7 to 9, wherein the further
tubular element (46) is of circular section.
11. A pressurised metered dose inhaler comprising the actuator of
any of claims 1 to 10 and a canister (2) including a valve stem
(14) extending therefrom.
Description
[0001] The present invention relates to an actuator for a
pressurised metered dose inhaler and a pressurised metered dose
inhaler including the same.
[0002] In using conventional pressurised metered dose inhalers with
some hydrofluoroalkane (HFA) formulations being developed by the
applicant company it has been found that medicament tends to
deposit in the valve stems of the canisters thereof. It will be
appreciated that this deposition could lead to the user receiving
an unusually high dose of medicament if the deposit were at least
in part to break away or, indeed, result in the valve stems
becoming blocked, thereby rendering the pressurised metered dose
inhalers inoperative. Ideally, one would simply Just wash the
canisters to remove the deposit. Unfortunately, however, it is not
possible to wash the canisters as the formulations are sensitive to
moisture and would as a result of washing be contaminated.
[0003] Accordingly, the present invention provides an actuator for
a pressurised metered dose inhaler, including: a tubular section
providing an outlet through which medicament is in use inhaled; and
a nozzle block including a tubular element having a free end over
which the valve stem of a canister is in use located and a spray
orifice in fluid communication with the tubular element for
directing a spray into the tubular section.
[0004] By providing the nozzle block of the actuator with a tubular
element over which the valve stem of a canister is located,
medicament will deposit on the inner radial surface of the tubular
element and not in the valve stem of the canister. In this way, the
user is able to prevent the build up of any appreciable amount of
deposit by washing the actuator regularly: the actuator being
washable when separated from the canister.
[0005] Preferably, the tubular element is configured such that an
outer radial surface thereof is a close fit with an inner radial
surface of the valve stem of the canister.
[0006] More preferably, the tubular element is configured such that
an outer radial surface thereof is a tight fit with an inner radial
surface of the valve stem of the canister.
[0007] Preferably, the tubular element is of circular section.
[0008] Preferably, the nozzle block includes an abutment against
which in use bears the distal end of the valve stem of the
canister.
[0009] More preferably, the abutment comprises a surface which
extends radially outwardly of the tubular element.
[0010] In a preferred embodiment the nozzle block includes a
further tubular element co-axial with the first-mentioned tubular
element such that the tubular elements define an annular channel in
which the valve stem of the canister is in use located.
[0011] Preferably, the further tubular element is configured such
that an inner radial surface thereof is a close fit with an outer
radial surface of the valve stem of the canister.
[0012] More preferably, the further tubular element is configured
such that an inner radial surface thereof is a tight fit with an
outer radial surface of the valve stem of the canister.
[0013] Preferably, the further tubular element is of circular
section.
[0014] The present invention also extends to a pressurised metered
dose inhaler comprising the above-described actuator and a canister
including a valve stem extending therefrom.
[0015] A preferred embodiment of the present invention will now be
described hereinbelow by way of example only with reference to the
accompanying drawings, in which:
[0016] FIG. 1 illustrates a front view of an actuator of a
pressurized metered dose inhaler in accordance with a preferred
embodiment of the present invention;
[0017] FIG. 2 illustrates a side view of the actuator of FIG.
1;
[0018] FIG. 3 illustrates a vertical sectional view of the actuator
of FIG. 1; and
[0019] FIG. 4 illustrates a vertical sectional view the pressurised
metered dose inhaler of the preferred embodiment of the present
invention.
[0020] The pressurised metered dose inhaler comprises an actuator 1
and an aerosol canister 2 fitted therein.
[0021] The canister 2 comprises a body 4 which defines a storage
chamber 6 for holding a suspension or solution of a medicament in a
propellant under pressure. The body 4 includes a head 8 which
includes a housing 10 that defines a metering chamber 12 and a
valve stem 14 that is movably disposed in the housing 10 and
extends from the head 8. The valve stem 14 is movable between an
extended, closed position (as illustrated) and a depressed, open
position (not illustrated), the valve stem 14 normally being biased
by a compression spring 16 disposed in the housing 10 into the
closed position. The valve stem 14 includes a first conduit 18
which includes a first, outlet opening 20 located at the distal end
of the valve stem 14 and a second, inlet opening 22 located in the
side wall of the valve stem 14. The valve stem 14 further includes
a second conduit 24 in that part thereof which is always disposed
within the body 4. The second conduit 24 includes first and second
axially-spaced openings 26, 28 located in the side wall of the
valve stem 14 and enables communication between the storage chamber
6 and the metering chamber 12 via bores 30 in the housing 10. In
this regard. it will be noted that the structure of the metering
chamber 12 and the valve stem 14 of the canister 2 is known per
se.
[0022] The actuator 1 comprises a first, main tubular section 32,
one, the upper, end of which is open and provides an opening 34
into which the canister 2 is in use inserted and the other, lower,
end of which is closed by a wall member 36. The actuator 1 further
comprises a second tubular section 38 which extends substantially
laterally from the other, that is, the lower, end of the main
tubular section 32; the second tubular section 38 acting as a
mouthpiece which is in use gripped in the lips of a user and
including an opening 40 at the distal end thereof through which
medicament is in use inhaled. The actuator 1 still further
comprises a nozzle block 42 which extends upwardly from the wail
member 36 into the main tubular section 32. The nozzle block 42
includes a first tubular element 44, in this embodiment of circular
section, over which the valve stem 14 of the canister 2 is located.
The first tubular element 44 is configured such that the radial
dimension of the outer radial surface thereof is a close fit with
the inner radial surface of the first conduit 18 in the valve stem
14. In this way, no appreciable amount of medicament can build up
between the outer radial surface of the first tubular element 44
and the inner radial surface of the first conduit 18 in the valve
stem 14. In a preferred embodiment the first tubular element 44 is
configured such that the radial dimension of the outer radial
surface thereof is a tight fit with the inner radial surface of the
first conduit 18 in the valve stem 14. In this way, material cannot
escape between the outer radial surface of the first tubular
element 44 and the inner radial surface of the first conduit 18 in
the valve stem 14. The first tubular element 44 is further
configured to be of such a length as to extend within the first
conduit 18 in the valve stem 14 to a position adjacent that part of
the second opening 22 in the valve stem 14 which is axially closest
to distal end of the valve stem 14. In this way, the second opening
22 in the valve stem 14 is always open. The first tubular element
44 is located on the longitudinal axis of the main tubular section
32. In this way, the valve stem 14 will always be aligned with the
first tubular element 44 on insertion of the canister 2 into the
actuator 1, thereby allowing easy fitting and removal. The nozzle
block 42 further includes a second tubular element 46, in this
embodiment also of circular section, which is co-axial with the
first tubular element 44 and is disposed such that the outer radial
surface of the first tubular element 44 and the inner radial
surface of the second tubular element 46 define an annular channel
48, the bottom surface 49 of which provides an abutment for the
distal end of the valve stem 14. The second tubular element 46 is
configured such that the radial dimension of the inner radial
surface thereof is a close fit with the outer radial surface of the
valve stem 14. In this way, lateral movement of the valve stem 14
is prevented, thereby ensuring that the first tubular element 44
cannot be damaged by such lateral movement of the valve stem 14. In
a preferred embodiment the second tubular element 46 is configured
such that the radial dimension of the inner radial surface thereof
is a tight fit with the outer radial surface of the valve stem 14.
In this way, material cannot escape between the outer radial
surface of the valve stem 14 and the inner radial surface of the
second tubular element 46. The nozzle block 42 still further
includes a laterally-directed spray orifice 50 which is in fluid
communication with the first tubular element 44 and configured to
direct a spray into the second tubular section 38 acting as the
mouthpiece.
[0023] In use, a user grips the mouthpiece provided by the second
tubular section 38 in the lips. The user then depresses the base of
the body 4 of the canister 2 which extends out of the opening 34 in
the main tubular section 32 so as to release a dose of medicament
from the canister 2 and at the same time inhales so as to inhale
the dose of medicament.
[0024] In this embodiment the actuator 1 is formed entirely of a
plastics material, typically by moulding. In an alternative
embodiment the first tubular element 44 could be provided by a
preformed thin-walled metal tube, such as a stainless steel tube,
to which is fitted or moulded a component providing the remainder
of the actuator 1.
[0025] Finally, it will be understood that the present invention
has been described in its preferred embodiment and can be modified
in many different ways without departing from the scope of the
invention as defined by the appended claims.
* * * * *