U.S. patent application number 10/137007 was filed with the patent office on 2003-11-06 for aerosol medication inhalation system.
This patent application is currently assigned to PRE HOLDING, INC.. Invention is credited to Gallem, Thomas, Gowanlock, Kevin Grant, Lynch, Robert Carlton.
Application Number | 20030205226 10/137007 |
Document ID | / |
Family ID | 29215686 |
Filed Date | 2003-11-06 |
United States Patent
Application |
20030205226 |
Kind Code |
A1 |
Gallem, Thomas ; et
al. |
November 6, 2003 |
Aerosol medication inhalation system
Abstract
An apparatus for use in conjunction with a metered dose inhaler
which includes a novel valve system to aid in the delivery of
aerosolized medicament to a subject. The apparatus also includes a
novel rotational flow generator to aid in the useable delivery of
said medication and avoid its loss either in the apparatus or by
non-useful delivery to said subject.
Inventors: |
Gallem, Thomas; (Munchen,
DE) ; Gowanlock, Kevin Grant; (London, CA) ;
Lynch, Robert Carlton; (Apex, NC) |
Correspondence
Address: |
MERCHANT & GOULD PC
P.O. BOX 2903
MINNEAPOLIS
MN
55402-0903
US
|
Assignee: |
PRE HOLDING, INC.
2943 Oak Lake Blvd.
Midlothian
VA
23112
|
Family ID: |
29215686 |
Appl. No.: |
10/137007 |
Filed: |
May 2, 2002 |
Current U.S.
Class: |
128/200.14 ;
128/203.12 |
Current CPC
Class: |
A61M 15/0016 20140204;
A61M 15/0018 20140204; A61M 15/009 20130101; A61M 15/0086 20130101;
A61M 2206/16 20130101; A61M 15/0021 20140204; A61M 2205/0233
20130101 |
Class at
Publication: |
128/200.14 ;
128/203.12 |
International
Class: |
A61M 011/00; A61M
015/00; A61M 016/10 |
Claims
What is claimed is:
1. An apparatus for aerosol medication delivery, comprising: a
holding chamber having a first and second ends, the first end being
adapted to accept a source of aerosol medicament; and a mouthpiece
member provided at the second end of the holding chamber, for
delivering aerosol medicament to a subject, the mouthpiece member
comprising: a housing defining a passage through which aerosol
medicament can be supplied to a subject and comprising a sidewall
in which an opening is formed that opens to the outside of the
housing; and a one-piece valve member comprising a first valve
element in the passage that permits delivery of aerosol to a
subject during inhalation and blocks the passage during exhalation
and a second valve element that blocks the opening in the sidewall
of the housing during inhalation and is movable away from the
opening to permit the flow of air to the outside of the housing
from the passage during exhalation.
2. The apparatus of claim 1, wherein the housing defining the
passage comprises a delivery member and an adaptor member, the
adaptor member is provided at the second end of the holding
chamber, and the delivery member is releasably connected to the
adaptor member.
3. The apparatus of claim 2, wherein the opening in the sidewall of
the mouthpiece member is provided in the adaptor member.
4. The apparatus of claim 2, wherein the opening in the sidewall of
the mouthpiece member is provided in the delivery member.
5. The apparatus of claim 2, wherein the opening in the sidewall is
defined by a notch defined in an edge of the adaptor member and a
notch defined in an edge of the delivery member.
6. The apparatus of claim 2, wherein the delivery member is
releasably connected to the adaptor member by a quick-release
mechanism.
7. The apparatus of claim 6, wherein the quick-release mechanism
comprises a flexible wall disposed on one of the adaptor member or
the delivery member, the flexible wall comprising an engaging
member that releasably engages the other of the adaptor member or
the delivery member.
8. The apparatus-of claim 7, wherein the flexible wall comprises a
positioning element adapted for a human digit, placed to define a
location for flexing the wall to release the engaging member.
9. The apparatus of claim 1, wherein the mouthpiece is sized and
shaped to fit a human mouth.
10. The apparatus of claim 1, wherein the delivery member is
provided with a ridge.
11. The apparatus of claim 10, wherein the ridge is adapted for
attaching a mask.
12. The apparatus of claim 1, wherein the housing has a stop
element that limits the range of motion of the second valve element
in the direction of the passage.
13. The apparatus of claim 12, wherein the stop element is disposed
on the delivery member.
14. The apparatus of claim 1, wherein the first valve element is a
duck-bill valve.
15. The apparatus of claim 1, wherein the valve element is composed
of a flexible material.
16. The apparatus of claim 1, wherein the second valve element is a
hinged flap that seats adjacent the opening in the sidewall.
17. The apparatus of claim 2, wherein the first valve element and
the second valve element are joined together at a valve base.
18. The apparatus of claim 17, wherein the valve base forms a
substantially airtight seal between the delivery member and the
adaptor member.
19. The apparatus of claim 2, wherein the adaptor member and the
delivery member define first and second opposed surfaces and the
valve member is held between the first and second opposed
surfaces.
20. The apparatus of claim 19, wherein one of the delivery member
and the adaptor member comprises a plurality of pins that extend
from one of the first and second opposed surfaces and the other of
the delivery member and the adaptor member comprises openings for
accepting the pins.
21. The apparatus of claim 20, wherein the valve member is provided
with openings through which the pins extend.
22. The apparatus of claim 5, wherein the notch of the delivery
member and the notch of the adaptor member are aligned radially
when the mouthpiece is assembled.
23. The apparatus of claim 22, wherein the second valve element is
disposed between the notches.
24. The apparatus of claim 2, wherein one of the delivery member or
the adaptor member comprises a pair of radially spaced walls and
the other of the delivery member or the adaptor member comprises a
wall that extends into the space between the spaced walls.
25. The apparatus of claim 1, wherein the mouthpiece member has a
first end adapted to the second end of the holding chamber and a
second end for delivery of the aerosol medicament, which has an
oval shape in lateral cross section.
26. The apparatus of claim 1, wherein the housing of the mouthpiece
member has inner and outer walls disposed at and in contact with
the holding chamber such that the second end of the holding chamber
extends into a space between the inner and outer walls.
27. The apparatus of claim 1, wherein the mouthpiece member is
connected to the holding chamber by an adhesive.
28. The apparatus of claim 1, wherein the mouthpiece is formed of a
transparent material.
29. The apparatus of claim 1, wherein the housing is formed from a
transparent material.
30. The apparatus of claim 2, wherein the adaptor member is
substantially frustoconical in shape.
31. The apparatus of claim 2, wherein the adaptor member is formed
from a transparent material.
32. The apparatus of claim 2, wherein the delivery member is formed
from a transparent material.
33. The apparatus of claim 1, wherein the holding chamber is
cylindrical.
34. The apparatus of claim 33, wherein the holding chamber is
formed of metal.
35. The apparatus of claim 1, wherein the holding chamber is
treated with an anti-electrostatic coating.
36. The apparatus of claim 1, further comprising a receptacle
member at the first end of the holding chamber, having an opening
adapted to receive an outlet of an aerosol generating device.
37. The apparatus of claim 36, wherein the opening in the
receptacle member is capable of accepting outlets of different
aerosol generating devices.
38. A mouthpiece member for aerosol medicament delivery, having
first and second ends, the first end being adapted to accept a
source of aerosol medicament and the second end being adapted for
delivering aerosol medicament to a subject, the mouthpiece member
comprising: a housing defining a passage through which aerosol
medicament can be supplied to a subject and comprising a sidewall
in which an opening is formed; and a one-piece valve member
comprising a first valve element that permits delivery of aerosol
to a subject during inhalation and blocks the passage during
exhalation and a second valve element that blocks the opening in
the sidewall of the housing during inhalation and is movable away
form the opening to permit the flow of air to the outside of the
housing from the passage during exhalation.
39. The mouthpiece of claim 38, wherein the housing comprises a
substantially frustoconical section.
40. An apparatus for aerosol medication delivery, comprising: a
mouthpiece member for delivering aerosol medicament to a subject, a
holding chamber having first and second ends, the mouthpiece member
being disposed at the second end of the chamber and a receptacle
member being disposed at the first end of the chamber, the
receptacle member comprising: an opening adapted to accept a source
of aerosol medicament, a vent permitting fluid communication for
the entry of outside air into the holding chamber, and a means for
imparting a rotational flow to the outside air entering the holding
chamber.
41. The apparatus of claim 40, wherein the opening of the
receptacle creates an airtight seal around the source of aerosol
medicament.
42. The apparatus of claim 40, wherein the receptacle member is
formed of a flexible material such that the receptacle member may
be removed from and replaced on the holding chamber without loss of
functionality.
43. The apparatus of claim 40, wherein the receptacle member has a
plurality of vents, disposed equidistantly around the receptacle
member.
44. The apparatus of claim 40, wherein the receptacle member
directs outside air to the wall of the interior of the holding
chamber, thus creating a flow of such air along the wall of the
holding chamber and reducing particulate deposit from the aerosol
medicament within the holding chamber.
45. The apparatus of claim 40, wherein the means to impart
rotational flow comprises at least one baffle disposed on the
receptacle member to direct air entering the holding chamber
through a vent into a rotational flow within the chamber.
46. The apparatus of claim 42, wherein the receptacle member has a
lip around the perimeter of the receptacle member, which encloses
the first end of the holding chamber.
47. The apparatus of claim 40, wherein the mouthpiece member
comprises support ribs for supporting the source of aerosol
medicament.
48. The apparatus of claim 47, wherein the opening of the
receptacle member is defined by a collar that extends inward and
may be pushed up against the support ribs for retaining the source
of aerosol medicament.
49. The apparatus of claim 48, wherein the support ribs are
oriented radially when viewed in lateral cross section.
50. The apparatus of claim 45, wherein the baffle is a cyclone
baffle.
Description
BACKGROUND
[0001] The present invention is directed to apparatus for
delivering aerosol medicament to a subject in need of the
medicament. Delivery systems start with an aerosol-generating
device. One common example of such devices is a pressurized metered
dose inhaler (MDI). MDIs use pressurized gases to disperse
medicament as tiny particles or droplets for delivery to the
subject. By depressing the MDI, a known quantity of gas, and
thereby of medicament, is ejected from the MDI. MDIs have been used
with various types of diverse apparatus, in attempts to improve the
delivery of this known quantity of medicament to the subject. Some
problems associated with the delivery of medicament in an aerosol
form include, but are not limited to, wastage of medicament in the
delivery apparatus, delivery at too high speeds so that medicament
sticks to the back of the subject's throat or is inhaled into the
subject's sinuses rather than being received into the lungs,
ejection of medicament out of the apparatus towards a subject
without inhalation thereby, and ejection of medicament from the MDI
upon exhalation by the subject into the apparatus prior to
inhalation.
SUMMARY OF THE INVENTION
[0002] In one aspect, the present invention provides a mouthpiece
with a valve for controlling the delivery of aerosolized medicament
to a subject. The mouthpiece includes a housing that defines a
passage through which the medicament flows to the subject. The
housing has a one-piece valve system that permits passage of
medicament aerosol to the subject during inhalation, but does not
permit the passage of the subject's breath in the upstream
direction during exhalation, with the exhaled breath being expelled
through an opening in the sidewall of the housing.
[0003] Another aspect of the present invention combines this
mouthpiece and valve system with a holding chamber, which is
disposed between the mouthpiece and the source of aerosol. In a
further feature of this aspect of the invention, the interior of
the holding chamber has anti-electrostatic properties to reduce the
amount of medicament adhering to the walls of the holding chamber
and thereby increase the delivery efficiency of the system.
[0004] In a further aspect of the present invention, a holding
chamber is provided with a receptacle member adapted to accept a
source of aerosol medicament. The receptacle member may aid in the
efficient delivery of medicament to the subject, for example by
being vented to allow outside air to be mixed with the medicament
aerosol in the holding chamber. In addition, if a rotation is
imparted to the outside air brought into the holding chamber, the
adhesion of medicament to the walls of the holding chamber can be
reduced and the effort necessary to inhale through an apparatus of
this type may be reduced.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is an assembled view of an example of the aerosol
medicament delivery apparatus of the present invention.
[0006] FIG. 2 is a perspective exploded view of the apparatus.
[0007] FIG. 3 is a side view of the delivery member used in the
apparatus.
[0008] FIG. 4 is a bottom perspective view of the delivery
member.
[0009] FIGS. 5a and 5b are top and bottom views of the valve
element used in the apparatus.
[0010] FIG. 6 is a top perspective view of the delivery member.
[0011] FIG. 7 is a sectional side view of the adaptor member used
in the apparatus.
[0012] FIG. 8 is a top perspective view of the adaptor member.
[0013] FIGS. 9a and 9b are top and bottom views of the receptacle
member used in the apparatus.
DETAILED DESCRIPTION
[0014] Referring to FIGS. 1 and 2, the aerosol medicament delivery
apparatus 10 of the present invention is composed of a holding
chamber 200 with first and second ends. At the first end of the
holding chamber is a receptacle 300 for connection to a source of
aerosol medication. For the purposes of the present invention,
aerosol medicament or aerosol medication is intended to include
finely divided solid or liquid materials that are carried by a gas
for delivery to a subject's respiratory tract, especially to the
lungs. This includes nebulized materials. The medicament and
carrier gas aerosol composition can be prepared prior to use if it
exhibits sufficient physical and chemical stability, or it can be
prepared in situ from sources of solid or liquid medicament
materials (either in pure form or combined with a suitable solid or
liquid solvent, excipient or diluent) and pressurized gas.
[0015] At the second end is a mouthpiece member 100 for delivering
aerosol medicament to a subject through a valve 150. The mouthpiece
member includes a housing 101 that defines a passage 102 through
which aerosol medicament can be supplied to a subject and has an
opening 103 that opens to the outside of the housing. The valve,
discussed below, is of one-piece construction. During inhalation
the valve permits the flow of aerosol medicament from the holding
chamber to the subject, while blocking the inflow of outside air to
the passage 102 through the sidewall of the housing of the
mouthpiece member. During exhalation, the valve blocks the flow of
exhaled air upstream in the direction of the holding chamber, and
permits the exhaled air to be exhausted through the sidewall of the
housing.
[0016] In an exemplary embodiment, the housing 101 is composed of a
delivery member 110 and an adaptor member 170. The opening 103 may
be defined, as it is in part in the exemplary embodiment, by a
notch 186 in the adaptor member. The delivery member and adaptor
member may be releasably connected by a quick release mechanism
182. In the exemplary embodiment, the quick release mechanism is a
flexible wall, upon which a positioning element 175 may be located.
Also, in the exemplary embodiment, the housing is transparent. This
has the advantage that it allows for the subject to visually verify
the operation of the valve, to ensure opening and closing during
treatment.
[0017] Referring to FIG. 3, the delivery member 110 may include a
subject side section 120, a connecting ring 130, and an adaptor
side section 140. In the exemplary embodiment, the subject side
section of the delivery member of the mouthpiece is sized and
shaped to fit a human mouth, e.g. having an oval shape. The subject
end section is defined by a housing composed of a sidewall having a
height 124, and upon which may be provided at least one ridge 125.
Positioning pins 141 may be provided on the adaptor side section of
the delivery member.
[0018] Referring to FIG. 4, the adaptor side section 140 of the
delivery member 110 in this exemplary embodiment has walls 142
arranged around an opening 145. One or more openings, for example
the illustrated notches 147, is formed in the wall 142 and can
define an exhaust opening from the delivery member for exhaled air.
This opening is closed by the valve during inhalation, and the
opening may be provided with an element to assist in seating a
valve member, for example protrusion 146. The end face 144 of the
wall can be used as a surface for holding the valve in place when
the apparatus is assembled, in cooperation with an opposed surface
on the adaptor member. Also, in this embodiment, the four
positioning pins 141 extend from the end face of the wall 142.
[0019] Referring to FIGS. 5a and 5b, the one-piece two-way valve
system 150 allows for inhalation and exhalation with a single
valve. The valve has a base 151, a first valve element 152, which
has a duck-bill shape in this embodiment, and a second valve
element 153, which is shaped like a hinged flap 153 in this
embodiment. In the exemplary embodiment, the valve is composed of a
flexible material and there are two hinged flaps 153. The two valve
elements may be joined at or carried on a common base 151. The base
has a thickness 154 that is less than the height of the positioning
pins of the mouthpiece, so that the pins may pass therethrough.
There is an opening 155 in the base, which may be defined as the
perimeter of contact between the duck-bill and the base. The
exemplary embodiment has four positioning holes 156 placed near the
perimeter of the base, each being sized to admit the matching
positioning pins. Thus, when the apparatus is assembled, the
positioning pins of the mouthpiece penetrate the positioning holes
of the valve base and the valve base forms a substantially airtight
seal between the delivery member and the adaptor member.
[0020] The duck-bill is a shape predominantly that of a wedge with
a very narrow split across the apex of the wedge. The split is
narrow enough that the two edges forming the ends of the duck-bill
are substantially in contact when there is no external pressure on
the duck-bill. The duck-bill has a span, a height, and a thickness.
The height of the duck-bill is the vertical distance between the
apex of the wedge where the split is located and the base. The span
is the distance of the split across the thin edge of the wedge and
the height. The span is sufficiently narrow that the apex of the
duck bill will fit within the delivery member without contacting
it. Thus, the dead zone within the delivery member is minimized by
the valve extending therein. The valve may be as wide as possible
to provide for easier inhalation, but just narrower than the
passage so that the duck-bill sides do not receive pressure and the
lips of the duck-bill are not parted except by inhalation.
[0021] Dead space refers to the volume of the apparatus containing
air which is rebreathed. Dead space is inherent in any valve-based
system enclosed within a mouthpiece or mask; it is the space
between the mouth of a subject and the valve. Any subject has a
limited volume of air that may be inhaled, and which then is
exhaled. This is the subject's tidal volume. The inhalation air
will contain both oxygen and medicament. The exhalation air will
contain carbon dioxide. In a sealed system, all inhalation air will
come through the valve and will contain a preferable mixture of
medicament laden air. However, this inhalation air will be combined
with whatever gases remain sealed within the dead space on their
way to being actually inhaled into the subject's respiratory tract.
Similarly, when the subject exhales, all air must pass through this
dead zone on the way out the exhaust portion of the valve
system.
[0022] Because the subject will be incapable of forcing a complete
vacuum within this sealed system, the dead space will contain gases
that then will be re-inhaled during the next breathing cycle. Given
that the volume of the subject's lungs is fixed, the larger the
volume of the system's dead space, the smaller the volume of
medicament laden air the subject will receive with each breathing
cycle. Thus, the larger the volume of dead space, the less
efficient the system because increasing dead space causes a buildup
of carbon dioxide and rebreathing. Rebreathing carbon dioxide can
have an adverse effect on breathing rates and patterns, especially
for small children who have very small tidal volumes. Duck-bill
valves are more efficient than diaphragm valves because the volume
encompassed by the duck-bill is subtracted from space that
otherwise would be dead space in a diaphragm-based system.
[0023] The duck-bill is thin enough that the sides of the wedge
will flex when the atmospheric pressure on the opposite side of the
base from the duck-bill is greater than that above the duck-bill.
This causes the edges of the duck-bill to part, letting air flow
through the duck-bill in the direction from the base to mouthpiece.
Thus, in the present embodiment, air is permitted to flow through
the mouthpiece to a subject during inhalation. The duck-bill closes
automatically at the end of inhalation when the atmospheric
pressure differential is removed. Thus, the flow of exhaled air
upstream of the valve to the holding chamber is prevented during
exhalation.
[0024] The exemplary embodiment of the present invention provides
two hinged flaps 153 extending from on or near the perimeter of the
base. Each hinged flap 153 is sized so as to be able to cover a
corresponding notch 147 when assembled. Each flap is placed on the
base at such a position and at such an angle that when the base is
placed onto the positioning pins of the mouthpiece, the flap covers
one of the notches 147. The flap is hinged onto the base so that it
may cover the notch 147 during inhalation, thereby preventing the
flow of outside air into the interior of the housing through the
opening in the sidewall of the housing. When the mouthpiece of the
apparatus of the exemplary embodiment is assembled, the notch of
the delivery member 147 and the aforementioned notch of the adaptor
member 186 may be aligned radially, and the hinged outgas flap 153
is disposed between these notches. The flexible material forming
each of the outgas flaps is sufficiently thin to allow an outgas
flap to flex through at least a few degrees of flexibility when
differences in relative atmospheric pressure caused by human
breathing exert flexing pressure on said flap, thereby moving the
flap away from the notch 147 during exhalation and allowing exhaled
air to pass out of the mouthpiece through the notch 186.
[0025] Referring to FIG. 6, the subject side section 120 of the
delivery member may be formed by a sidewall 128 that is generally
cylindrical in shape with an oval cross section. The exemplary
embodiment has two side points 122, opposite each other on the
sidewall, and two lip points 123, opposite each other on the
sidewall. Each lip point is equidistant between the two side
points. There is a contact end 126 where the sidewall is joined to
the connecting ring and a lip end 127 opposite the contact end. The
upper opening of the sidewall 121 at the lip end is oval. There is
a lower opening of the sidewall at the contact end, through which
the tip of the duck-bill valve passes.
[0026] Ridges 125 may be provided for placement of the subject's
lips, or to aid in the placement of an adaptor mask on the outside
of the delivery member. Shaped correctly, a ridge 125 may be used
to seal and mount such a mask with a tight pressure fit. These
ridges are placed approximately halfway down the upper section, and
are wedge shaped in the exemplary embodiment. Specifically, they
are formed by the upper and lower thickness measurements being
equal at the side points and the lower thickness being greater than
the upper thickness at the lip points.
[0027] Referring to FIGS. 4 and 6, the connecting ring 130 between
the adaptor side and subject side sections of the delivery member
has an interior opening 135, which may be equal in size to and
substantially continuous with the opening of the sidewall of the
subject side section. It has an exterior limit 131 that is greater
than the interior opening, and a surface 132 where the connecting
ring is joined to the subject side section. The surface 132 extends
from the sidewall 128 outwards toward the exterior limit 131 where
it joins with an exterior wall 133.
[0028] The exterior wall 133 may be substantially parallel to the
sidewall 128 and extends from the top surface in a direction away
from the lip end of the subject side section. The exterior wall has
an interior surface and an exterior surface, the interior surface
being closer to the interior opening of the connecting ring. In the
exemplary embodiment, there are two contact openings 134 in the top
surface, which are disposed approximately equidistantly around the
circumference of the top surface. Each contact hole is adapted to
accept a portion of the adaptor member, to help hold the two
members of the mouthpiece securely together. On the interior
surface of the exterior wall, there may be provided two engaging
members 136, or catches, each being below a contact hole. They are
wedge shaped and oriented with the thin end of the wedge towards
the adaptor side for ease in connecting and resistance to
disconnecting. In the exemplary embodiment, each has a width less
than that of the corresponding contact opening above the catch, a
length less than that of the distance between the top and bottom of
the exterior wall of the connecting ring, and a height less than
the length.
[0029] Referring back to FIGS. 3 and 4, the width 143 of each
section that makes up the wall 142 is approximately as wide as a
contact opening in the top surface of the connecting ring. Each
wall section is disposed along the interior opening substantially
adjacent to a contact opening, thus providing a limit to the
flexing of the walls of the adaptor member, which is discussed
below. In the exemplary embodiment, each wall section has two
positioning pins 141 placed along the end face of the wall,
extending in the same direction. They are placed near the edge of
the wall sections, and can be placed as far apart from each other
as the width of a contact opening in the surface of the connecting
ring. Due to their height, the sections of the wall 142 extend into
the space of the adaptor member when the apparatus is assembled.
Protrusions 146 may be disposed on the perimeter of the opening
forming the passage for exhalation air flow (notches 147). These
protrusions act as stop elements for the exhaust flap portions of
the one-piece valve, limiting their travel in an inward direction.
As will be seen in more detail below, when the subject inhales,
these exhaust flaps are pressed by suction against the stop
elements and form a seal so that the pressure of inhalation is
fully directed towards drawing the medicament laden air from the
holding chamber.
[0030] Referring to FIG. 7, the adaptor member 170 may be generally
frustoconical in shape, thereby providing for the smooth change in
diameter from the holding chamber to the delivery member. In the
exemplary embodiment, it is both frustoconical and transparent. A
transparent embodiment of the present invention has the additional
advantage of allowing the subject to visually verify the presence
of the medicament during delivery to the patient. The adaptor
member may have a base end 171, a conical midsection 172, four wall
sections, and a delivery side end 173. The base end is adapted to
cooperate with the edge of the holding chamber, for example forming
an exterior wall extending from the end of the cone. The base end
of the adaptor member also may have an inner wall 174 extending
from the end of the cone. In the exemplary embodiment, each of
these two walls having a height of at least 0.5 mm to define a
groove for accepting the edge of the holding chamber. In this case,
the walls are shaped and positioned such that, when the chamber is
positioned between the inner and outer walls and a thin layer of
adhesive is applied between the walls, a substantially airtight
seal may be formed between the holder and the chamber. Other
systems for joining the adaptor member and holding chamber may be
used, including permanent bonding or releasable connections. The
releasable connection may not be needed when the delivery member is
made of two readily-separated components that allow for easy
cleaning and for replacement of the valve when necessary, as in the
illustrated embodiment.
[0031] Referring to FIGS. 7 and 8, the wall arising from the
frustoconical midsection 172 of the adaptor member 170 may be
divided into four sections, including two catch walls 176 and two
vent walls 177 in the exemplary embodiment. These may be placed
alternately around the delivery side end of the adaptor member.
Each catch wall 176 may have a catch opening 178 sized to admit one
of the catches 136 of the connecting ring 130 of the delivery
member 110. A catch wall 176 is positioned on the adaptor member
such that its opening 178 is adapted to fit a catch 136 when the
two adaptor and delivery members are joined. The end 179 of the
catch wall 176 may fit a contact opening 134 of the connecting ring
130 of the delivery member 110. The catch walls 176 may be
flexible, so that they may be bent by the subject applying pressure
at the positioning points 175 to release the catch 136 from the
opening 178. This allows the two members of the exemplary housing
101 to be joined and separated in a quick-release fashion. Each
valve wall 177 in the exemplary embodiment is U shaped. That is, it
is a wall on the long side of the oval opening with a notch 186 in
it. Other systems for connecting the adaptor member and delivery
member can be used. In addition, the catch and opening could be
reversed, i.e. the opening provided on the connecting ring and the
catch provided on wall section of the adaptor member.
[0032] The delivery side end of the conical adaptor member may have
an opening 185 of substantially the same size as the opening 155.
An airtight seal may be formed between the opposing surfaces of the
adaptor member and the delivery member by the valve. That is, the
valve base 151 may have opposing surfaces arranged to meet those of
the adaptor member and the delivery member and form an airtight
seal when the apparatus is assembled. The exemplary embodiment's
adaptor member 170 has a rim 180 around the opening 185 with four
positioning openings 181 in the rim, one for each pin 141. Thus,
when the two members are joined, the four pins of the delivery
member drop into these openings in the exemplary embodiment.
[0033] Referring to back FIGS. 1, 2 and 7, the cylindrical holding
chamber 200 may be defined by a length of cylindrical tube that
extends between the mouthpiece 100 and a source of aerosol
medicament and includes the receptacle 300 accepting an outlet from
a source of aerosol medicament such as a metered dose inhaler or
the like. The tube wall 201 may be sized to fit between the inner
wall 174 and the outer wall 171 of the base of the mouthpiece. In
the exemplary embodiment, the holding chamber is made of a
lightweight metal or alloy, such as aluminum or an alloy
thereof.
[0034] The use of such material reduces the risk of resistance to
medicament flow by static attraction between the particles of
medicament and the holding chamber wall. Alternatively, the surface
of a holding chamber of any material may be treated with an
anti-electrostatic coating or process to achieve this advantage. In
the exemplary embodiment using a metal tube, the tube is anodized
which provides the advantage of sealing the micro-porosity of such
a tube's surface and stabilizing it against oxidation.
[0035] Referring to FIGS. 9a and 9b, the receptacle 300 may include
a base with a lip 310, an opening 350 for accepting a source of
aerosol medicament in the base with a collar 370 extending into the
chamber 200, an air vent 320, and a supporting wall 340 that
surrounds the opening arising from the base into the chamber. The
exemplary embodiment has four vents. The receptacle base is sized
to fit within the tube of the holding chamber. It may be formed of
a resilient and flexible material such that it may be removed from
the chamber tube (e.g., for cleaning) and replaced many times
without loss of functionality, such as maintenance of structural
integrity or the ability of the receptacle to form a substantially
airtight seal with the tube, throughout the life of the apparatus.
In the exemplary embodiment, the receptacle may be removed and
replaced hundreds of times without ripping, tearing or otherwise
harming the functionality of the apparatus. This removal resilience
also applies to the removal and replacement of the source of
aerosol medicament from the apparatus. The lip 310 of the
receptacle fits around the perimeter of the base of the member so
that the lip extends beyond the edge of the tube. The lip may be
sized such that it forms a substantially airtight seal with the
tube. Other systems can be used to join the receptacle to the tube
if desired.
[0036] The opening 350 of the receptacle of the exemplary
embodiment may be sized to accept several different types of
aerosol medicament sources such as MDIs. The collar 370 is
sufficiently long and flexible to form a seal with the aerosol
medicament source when one is admitted into the receptacle. The
supporting wall 340 of the exemplary embodiment is provided with
cyclone baffles 330 placed upon the outside of the wall (relative
to the opening) and support ribs 360 radially placed upon the
inside of the wall. The support ribs 360 extend from the wall
towards the collar 370. They are sized so that there is space for
the collar to be pressed up against the ribs when a typical MDI is
inserted into the opening. Thus, an airtight seal may be formed
around the source of the aerosol medicament. The support ribs of
the exemplary embodiment provide support to the source of aerosol
medicament by holding that source against the structure of the
collar.
[0037] The vents 320 allow outside air to be drawn into the holding
chamber during inhalation. This helps to push the aerosol
medicament to the subject during inhalation. Each cyclone baffle
330 extends towards the base and is aligned with a vent 320 so that
the point where the baffle reaches the base is just beyond the
vent. The baffle thus covers the vent. The baffle may have a width
sufficient to form a seal between the supporting wall and the tube
wall of the chamber. By using the baffle to direct airflow coming
through the vents, a rotational flow is imparted to the air
entering the chamber through the vents. In the exemplary
embodiment, the placement of the cyclone baffles above the vents
and next to the wall of the holding chamber wall directs outside
air to and along the wall of the holding chamber. This reduces the
tendency for medicament to adhere to the wall of the holding
chamber. Although each of the four vents have been provided with a
cyclone baffle in the present embodiment, this may not be necessary
in all cases.
[0038] The exemplary embodiment of the present invention is steam
autoclavable either assembled or disassembled. This advantage
arises from both the choice of materials used, as herein discussed,
and the materials and methods of assembling the components of the
invention, such as the quick release mechanism 182 and the use of
high-temperature adhesive at the junction of adaptor member 170 and
holding chamber 200. Further, the present invention is easily
disassembled for cleaning and parts replacement by a non-technical
person.
[0039] While a detailed description of the present invention has
been provided above, the invention is not limited thereto.
Modifications that do not depart from the scope and spirit of the
invention will be apparent to those skilled in the art. The
invention is defined by the claims that follow.
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