RESPIRATORY MASK ASSEMBLY FOR DELIVERING BREATHABLE GAS

MASQUE RESPIRATOIRE POUR L'ADMINISTRATION D'UN MELANGE GAZEUX RESPIRABLE

English Abstract

A respiratory mask assembly for delivering breathable gas to a patient
includes a
mask frame having a first cooperating interlocking structure. A cushion clip
having a
second cooperating interlocking structure is selectively detachable to the
mask frame.
The first and second cooperating interlocking structures interlock with one
another in a
cooperating relationship to secure the cushion clip on the mask frame. A mask
cushion
has a portion positioned between the mask frame and the cushion on the mask
frame.

French Abstract

Masque respiratoire pour l'administration d'un mélange gazeux respirable à un patient, qui comprend un cadre de masque muni d'une première structure interreliée coopérative. Une agrafe de coussinets comportant une seconde structure interreliée est sélectivement amovible du cadre du masque. Les deux structures interreliées coopératives s'enclenchent l'une à l'autre de manière coopérative pour fixer l'agrafe de coussinets sur le cadre du masque. Un coussinet de masque comporte une partie placée entre le cadre de masque et le coussinet sur le cadre du masque.

Claims

8

The embodiments of the invention in which an exclusive property of privilege
is claimed
are defined as follows:


1. A respiratory mask assembly for delivering breathable gas to a patient,
comprising:

a mask frame having a first cooperating interlocking structure;

a cushion clip having a second cooperating interlocking structure and being
selectively attachable to and detachable from the mask frame, the first and
second
cooperating interlocking structures interlocking with one another in a
cooperating
relationship to secure the cushion clip on the mask frame; and

a mask cushion having an outer peripheral portion positioned between the mask
frame
and the cushion clip so as to retain the mask cushion on the mask frame,

wherein the mask frame includes a plurality of recesses that provide the first

cooperating interlocking structure and the cushion clip includes a plurality
of tabs that is
equal in number to the plurality of recesses in the mask frame and provides
the second
cooperating interlocking structure, each of the plurality of tabs engaging a
respective
recess to secure the cushion clip on the mask frame.

2. A respiratory mask assembly according to claim 1, wherein the mask assembly
is
a full-face mask and wherein the mask frame includes six recesses.

3. A respiratory mask assembly according to any one of claims 1-2, wherein the

mask frame includes a rib extending around the periphery thereof and the mask
cushion
includes a groove extending around the periphery thereof, the groove of the
mask cushion
receiving the rib of the mask frame.



9

4. A respiratory mask assembly according to claim 3, wherein the mask cushion

includes an outwardly extending portion that provides the groove on one side
thereof, an
opposite side of the outwardly extending portion providing a shoulder that
engages a flange
on the cushion clip to retain the mask cushion on the mask frame.

5. A respiratory mask assembly according to any one of claims 1-4, wherein the

mask cushion includes a rearwardly extending portion structured to space the
mask frame
from the patient's face.

6. A respiratory mask assembly according to any one of claims 1-5, wherein the

frame includes a first side structured to accommodate the cushion, and a
second side,
opposite the first side, and wherein the cushion clip and frame are configured
to cooperate
with one another such that the cushion clip is selectively attachable to the
frame in a first
direction defined generally from the first side to the second side of the
frame, to thereby
secure the cushion between the cushion clip and the frame.

7. A respiratory mask assembly according to claim 6, wherein the cushion clip
and
frame are configured to cooperate with one another such that the cushion clip
is selectively
detachable from the frame in a second direction, opposite the first direction,
defined generally
from the second side to the first side of the frame, to thereby allow removal
of the cushion
from the frame.

8. A respiratory mask assembly for delivering breathable gas to a patient,
comprising:




a mask frame having a first cooperating interlocking structure;

a cushion clip having a second cooperating interlocking structure and being
selectively attachable to and detachable from the mask frame, the first and
second
cooperating interlocking structures interlocking with one another in a
cooperating
relationship to secure the cushion clip on the mask frame; and

a mask cushion having a portion positioned between the mask frame and the
cushion
clip;

wherein the mask frame includes a plurality of recesses that provide the first

cooperating interlocking structure and the cushion clip includes a plurality
of tabs that is
equal in number to the plurality of recesses in the mask frame and provides
the second
cooperating interlocking structure, each of the plurality of tabs engaging a
respective
recess to secure the cushion clip on the mask frame.

9. A respiratory mask assembly according to claim 8, wherein the frame
includes a
first side structured to accommodate the cushion, and a second side, opposite
the first side,
and wherein the cushion clip and frame are configured to cooperate with one
another such
that the cushion clip is selectively attachable to the frame in a first
direction defined generally
from the first side to the second side of the frame, to thereby secure the
cushion between the
cushion clip and the frame.

10. A respiratory mask assembly according to claim 9, wherein the cushion clip
and
frame are configured to cooperate with one another such that the cushion clip
is selectively
detachable from the frame in a second direction, opposite the first direction,
defined generally
from the second side to the first side of the frame, to thereby allow removal
of the cushion
from the frame.



11

11. A respiratory mask assembly according to any one of claims 8-10, wherein
the

first and second interlocking structures are engagable when the cushion clip
is moved in a
first direction defined generally from a first side of the frame that supports
the cushion
towards a second side of the frame opposite the first side, to thereby secure
the cushion
between the cushion clip and the frame.

12. A respiratory mask assembly according to claim 11, wherein the first and
second
interlocking structures are disengagable when the cushion clip is moved in a
second direction
defined generally from the second side towards the first side of the frame, to
thereby allow
removal of the cushion from the frame.

13. A respiratory mask assembly according to claim 12, wherein each said tab
is
resiliently movable in a third direction that is substantially transverse to
the first and second
directions, upon selective engagement and disengagement between the cushion
clip and the
frame.

14. A respiratory mask assembly for delivering breathable gas to a patient,
comprising:

a mask frame having a first cooperating interlocking structure;

a cushion clip having a second cooperating interlocking structure and being
selectively attachable to and detachable from the mask frame, the first and
second
cooperating interlocking structures interlocking with one another in a
cooperating
relationship to secure the cushion clip on the mask frame; and

a mask cushion provided to the mask frame,



12

wherein the mask frame includes at least a first recess positioned along a
first side of

the frame and a second recess positioned along a second side of the frame, the
first and
second recesses providing the first cooperating interlocking structure, and
wherein the
cushion clip includes at least a first tab positioned along a first side of
the cushion clip and a
second tab positioned along a second side of the cushion clip, the first and
second tabs
providing the second cooperating interlocking structure, the first and second
tabs being
engagable with the first and second recesses, respectively, to secure the
cushion clip on the
mask frame.

15. A respiratory mask assembly according to claim 14, wherein the frame
includes a first side structured to accommodate the cushion, and a second
side, opposite the
first side, and wherein the cushion clip and frame are configured to cooperate
with one
another such that the cushion clip is selectively attachable to the frame in a
first direction
defined generally from the first side to the second side of the frame, to
thereby secure the
cushion between the cushion clip and the frame.

16. A respiratory mask assembly according to claim 15, wherein the cushion
clip
and frame are configured to cooperate with one another such that the cushion
clip is
selectively detachable from the frame in a second direction, opposite the
first direction,
defined generally from the second side to the first side of the frame, to
thereby allow removal
of the cushion from the frame.

17. A respiratory mask assembly according to any one of claims 14-16, wherein
the mask frame includes a rib extending around the periphery thereof and the
mask cushion



13

includes a groove extending around the periphery thereof, the groove of the
mask cushion
receiving the rib of the mask frame.

18. A respiratory mask assembly according to claim 17, wherein the mask
cushion includes an outwardly extending portion that provides the groove on
one side thereof,
an opposite side of the outwardly extending portion providing a shoulder that
engages a
flange on the cushion clip to retain the mask cushion on the mask frame.

19. A respiratory mask assembly according to any one of claims 1-7, wherein
the
cushion clip is selectively attachable to and detachable from the cushion.

20. A respiratory mask assembly for delivering breathable gas to a patient,
comprising:

a mask frame having a first cooperating interlocking structure;

a cushion clip having a second cooperating interlocking structure and being
selectively attachable to and detachable from the mask frame, the first and
second
cooperating interlocking structures interlocking with one another in a
cooperating
relationship to secure the cushion clip on the mask frame; and

a mask cushion having an outer peripheral portion positioned between the mask
frame
and the cushion clip so as to retain the mask cushion on the mask frame,

wherein the cushion clip is selectively attachable to and detachable from the
cushion,
and

wherein the mask frame includes a rib extending around the periphery thereof
and the
mask cushion includes a groove extending around the periphery thereof, the
groove of the
mask cushion receiving the rib of the mask frame



14

21. A respiratory mask assembly according to claim 20, wherein the mask
cushion

includes an outwardly extending portion that provides the groove on one side
thereof, an
opposite side of the outwardly extending portion providing a shoulder that
engages a flange
on the cushion clip to retain the mask cushion on the mask frame.

Description

CA 02519452 2010-08-06

1
RESPIRATORY MASK ASSEMBLY FOR DELIVERING BREATHABLE GAS
BACKGROUND OF THE INVENTION

This invention relates to improvements in patient gas delivery apparatus of
the kind
used in the analysis and treatment f respiratory disorders. The invention will
be
described with particular reference to patient gas delivery apparatus used in
the
treatment of respiratory disorders such as Obstructive Sleep Apnea (OSA) but
it is not
intended to be limited thereto.

Patient gas delivery apparatus of the kind having a mask worn by a patient and
a gas
delivery conduit attached to the mask, is commonly used in the analysis and
treatment
of respiratory disorders. The gas conduit delivers a gas under pressure to the
patient.
It is necessary that the gas conduit is detachable from the mask to facilitate
cleaning.

Patient gas delivery apparatus typically includes at a minimum, a gas delivery
conduit
and a nose or full face mask. In sop cases it is a clinical requirement that
additional
components be included, such as means for CO washout, for example, vents, anti-

asphyxia valves and the like. In some cases, these additional components must
be
assembled in between the gas delivery conduit and the mask. Problems with
prior art
assemblies include:

(a) They may be inadvertently assembled without the additional components
(b) They may be incorrectly assembled, for example, incorrectly aligned

(c) During the course of treatment, the patient may inadvertently remove or
dismantle the assembly and incorrectly reassemble it.

SUMMARY OF THE INVENTION
The present invention is directed towards solving or ameliorating one or more
of these
problems. The invention will be described with reference to a full face mask
and an


CA 02519452 2000-02-08

2
anti-asphyxia valve, though other forms of mask and additional components may
be
used.

In one form, the invention resides in a patient gas delivery apparatus
including a mask
adapted for communication with a patient's airways, a gas flow generator and
gas
delivery conduit means, further including an assembly connected in series
between the
conduit means and the mask, said assembly being formed in at least two parts
connected by interengaging connecting means, said assembly further including
means
for connection to the mask, wherein connection of the assembly to the mask
prevents
disengagement of the interengaging connecting means such that said at least
two parts
of the assembly cannot separate whilst the assembly is connected to the mask.

In a further form of the invention, there is provided an assembly for
connection in
series between a gas delivery conduit means and a patient mask in a patient
gas
delivery apparatus, the assembly being formed in at least two parts connected
by
interengaging connecting means, said assembly further including means for
connection to the mask, wherein connection of the assembly to the mask
prevents
disengagement of the interengaging connecting means such that said at least
two parts
of the assembly cannot separate whilst the assembly is connected to the mask.
Preferably, the means for connection to the mask includes locking means
located on
the inner side of the mask, that is in the region of the mask that lies
adjacent the
patient's face, such that the assembly cannot be disconnected from the mask
until the
mask has been substantially removed from the patient.
Preferably also, the interengaging means connecting the two parts of the
assembly
includes detent means on a first of the parts which releasably engage a second
of the
parts, the detents being held in an engaged position by the mask whilst the
assembly is
connected to the mask.
Desirably, the mask and conduit are not adapted for direct interconnection
without the
assembly.


CA 02519452 2000-02-08

3
In one preferred form of the invention, the assembly may form a housing for
one or
more internal components, for example a valve member or a flow sensor.

Further preferred embodiments of the invention will now be described by way of
example only with reference to the accompanying drawings in which:

Figure 1 is a perspective view showing the mask, anti-asphyxia valve housing
and
conduit connection assembly;

Figure 2 is an exploded view of the anti-asphyxia valve and conduit connection
assembly; and

Figure 3 is an exploded view of the mask assembly.

In Figure 1 a mask frame is shown generally at 10. The mask is designed to be
worn
on a patient's face and is secured by means of straps (not shown) received by
attachment points 18.

A conduit end assembly is shown generally at 20, including an elbow part 26
having
at one end thereof a combined vent/connector piece 28. The elbow and
vent/connector piece together form a housing for an anti-asphyxia valve or
other
internal components (not shown). At the other end of the elbow is a detachable
swivel
tube 29 for connection of the gas delivery conduit 71 connected to a gas flow
generator 70 structured to supply pressurized gas (see Figure 1).
The mask 10 includes a circular aperture 12 sized to receive a mating portion
22 of
the vent/connector piece 28. The mating portion 22 has an annular groove 23
formed
therein that receives a locking means 30 in the form of a C-shaped clip
attached after
mating to the mask. The clip 30 has an outside diameter greater than the width
of the
aperture 12 and an inner diameter adapted to ensure a snug fit within the
annular
groove 23. The clip 30 is resilient and can expand sufficiently to allow the
clip to be
fitted into and removed from the groove 23. As shown in Figure. 1, the clip 30
is


CA 02519452 2000-02-08

4
located onto the mating portion 22 on the inside of the mask 10. In this
position, the
clip 30 is inaccessible while the mask is being worn by a patient. Once the
mating
portion 22 of the vent/connector piece 28 has been inserted through the
aperture 12
and the locking clip placed in the annular groove, the conduit end assembly 20
and the
mask 10 cannot be separated without first removing the mask from the patient.
An exploded view of the anti-asphyxia valve and conduit connector assembly is
shown in Figure 2.

The end of the elbow 26 adjacent the mask 10 is fitted with an anti-asphyxia
valve
arrangement that provides an air passage to the patient in the event of
failure of the
gas flow generator 70, including a valve membrane 27 fitted into the end of
elbow 26
and vents 31 in the vent/connector piece 28. During proper operation of the
gas flow
generator 70, the valve membrane remains in the orientation shown in FIG. 2,
closing
off the vents 31. In the event of a drop in pressure below a predetermined
level, the
valve membrane 27 flips to a reverse orientation, opening the vents 31.

Resilient detents 42 on the elbow 26 pass through and engage behind slot-
forming
formations 44 in the vent/connector piece 28 to provide releasable engagement
of the
two parts.

The vent/connector piece has a collar 47 that abuts a corresponding surface of
the
mask 10 to limit the distance that the vent/connector piece can be inserted
into the
mask aperture 12 (Figure 1). The corresponding surface is an annulus 50 having
a
protruding rim 51 the outer circumference of which preferably engages the
inner
surface of the detents 42 on insertion of the mating portion 22 into the
aperture 12.
This engagement prevents the detents from being pushed radially inwards
sufficiently
for the detents to disengage from behind the slot-forming formations 44, thus
preventing the elbow 26 and vent/connector piece 28 from separating whilst
still
attached to the mask frame 11, for example during patient treatment. The
result of this
is that the anti-asphyxia valve arrangement cannot be disassembled without
first
removing the elbow and vent/connector piece assembly from the mask. However,


CA 02519452 2006-03-15

once disconnected from the mask, the assembly may be readily separated for
cleaning
and then reassembled.

The other, distal end of elbow 26 has an enlarged diameter portion which
receives the
5 swivel tube 29, onto which a flexible gas conduit 71 may be fitted. The
swivel tube 29
has a pair of flanges 56 and 57 defining an annular groove 58 therebetween.
The end of
swivel tube 29 is inserted into the elbow 26 until the end flange 57 abuts an
inner surface
(not shown) within elbow 26. In this position the annular groove 58 is at
least partially
aligned with an annular groove 61 in the exterior of the elbow, which receives
a swivel
clip 41.

The swivel clip 41 has an inner diameter only slightly greater than the
diameter of the
groove 61, to ensure a snug fit within the groove. The clip 41 is resilient to
permit
sufficient expansion for attachment and removal of the clip from the groove.
The groove
61 has slots 59 which receive lugs 62 on the clip. These lugs rotatably engage
in the
groove 58 between flanges 56 and 57 of the swivel tube. The swivel tube
arrangement
thus acts as a rotatable coupling between the conduit and the elbow whilst
allowing
quick attachment and removal of the gas conduit from the elbow regardless of
whether
the assembly is attached to the mask at the time.

As shown in Figure 3, the mask includes a mask frame 11, cushion 13 and
cushion clip
14. The cushion is received on a rib 15 extending around the periphery of the
mask frame
11. The cushion is held to the rib by the cushion clip 14. The mask frame
includes
attachment points 18 that receive straps (not shown) for attaching the mask to
the patient,
an aperture 16 for receiving an air vent 17, and measurement ports 19.

The mask frame 11 includes a plurality of recesses 11.1 that provide a first
cooperating
interlocking structure and the cushion clip 14 includes a plurality of tabs
14.1 that is
equal to a number of recesses in the mask frame 11 and provides a second
cooperating
interlocking structure. The plurality of tabs 14.1 engages a respective recess
11.1 to
secure the cushion clip 14 on the mask frame 11.


CA 02519452 2006-03-15

6
The mask assembly, in the example shown in Figure 3, is a full face mask. As
shown in
Figure 3, the frame includes top and bottom recesses, two left side recesses
and two right
side recesses (not shown). The cushion clip 14 includes corresponding top and
bottom
tabs 14.1 as well as two right side tabs (both shown) and two left side tabs
(only one
shown).

The mask cushion includes a groove 13.1 extending around the periphery thereof
and the
groove of the cushion receives the rib 15 of frame 11.

The cushion 13 includes an outwardly extending portion 13.2 that provides the
groove
13.1 on one side thereof. An opposite side of the out en portion 13.2 provides
a shoulder
13.3 that engages a flange 14.2 on the cushion clip 14 to retain the cushion
13 on frame
11.

The cushion includes a rearwardly extending portion designated by reference
number
13.4. The cushion serves to seal the mask assembly on the patients face, and
is structured
to space the mask frame 11 from the patient's face.

The frame 11 includes a first side 11.2 structured to accommodate cushion 13
and a
second side 11.3. The cushion clip 14 and frame 11 are configured to cooperate
with one
another such that the cushion clip 14 is selectively attachable to the frame
11 in a first
direction 11.4 defined generally from the first side 11.2 to the second side
11.3 of the
frame, to thereby secure the cushion 13 between the cushion clip 14 and the
frame 11.
The cushion clip 14 and frame 11 are configured to cooperate with one another
such that
the cushion clip is selectively detachable from the frame 11 in a second
direction 11.5
opposite to the first direction 11.4 defined generally from the second side
11.3 to the first
side 11.2 of the frame 11, to thereby allow removal of the cushion 13 from
frame 11.
Each tab 14.1 is resiliently movable in a third direction 14.3 that is
substantially
transverse to the first and second directions 11.4 and 11.5. Tab portions 14.1
move in the
direction indicated by arrows 14.3 when the tab portions are snapped or flexed
into place
within recesses 11.1 and when they are removed therefrom.


CA 02519452 2006-03-15
7

While particular embodiments of this invention have been described, it will be
evident to
those skilled in the art that the present invention may be embodied in other
specific
forms without departing from the essential characteristics thereof. The
present
embodiments and examples are therefore to be considered in all respects as
illustrative
and not restrictive, the scope of the invention being indicated by the
appended claims
rather than the foregoing description, and all changes which come within the
meaning
and range of equivalency of the claims are therefore intended to be embraced
therein.

Representative Drawing