GB2453885A

GB2453885A - Mask with valve closure mechanism

Info

Publication number: GB2453885A
Application number: GB0901104A
Authority: GB
Inventors: Ian Trevor Dampney
Original assignee: Helmet Integrated Systems Ltd
Current assignee: Helmet Integrated Systems Ltd
Priority date: 2004-06-29
Filing date: 2004-06-29
Publication date: 2009-04-22
Anticipated expiration: 2024-06-29
Also published as: GB2415634B; GB2453885B; GB2415634A; GB0414563D0; GB0901104D0

Abstract

A breathing mask has an outlet port 10, an exhalation valve associated with the outlet port capable of being closed by the wearer in order to allow him to equalise pressure in the ear canals. The outlet may be covered by a figure piece 9 retained by spigot 11 and arranged to close when depressed.

Description

BREATHING EQUIPMENT

The present invention relates to breathing equipment and in particular to breathing masks, such as those worn by the pilots of military aircraft.

The pilot of a military aircraft typically wears a breathing mask which is attached by straps for, example, to a helmet. In order to provide environmental protection, it may be necessary to provide the pilot with a hood worn either under or over the helmet.

The mask has to be located within the hood so that a problem arises when connecting the mask to the helmet, in the event that the hood is worn under the IS helmet. If openings are provided in the hood to receive straps connecting the mask to the helmet, the openings will need to be sealed to ensure the integrity of the hood. If the seals become damaged or distorted in use, the health of the pilot may be placed at risk. Similar problems may arise in the case of breathing masks provided for use of those working in toxic atmospheres.

According to one aspect of the present invention the breathing mask has a component for location within the hood and a component for location externally of the hood, one of the components being provided or associated with a projection capable of being pressed into the material of the hood, and the other component having an opening for receiving and retaining the projection and the portion of the hood to which it is applied.

Preferably the projection has an enlarged head which, together with the portion of the hood, is retained in the opening eg. as a snap-fit. The projection may be of mushroom-like form and be provided on a face piece of the mask for reception, together with the portion of hood covering it, in an opening in a cover located on the outside of the hood. The cover is provided with fitments for attachment of straps securing the cover to the helmet. Although the opening in which the projection is received may pass entirely through the cover, it will be appreciated that the opening may be in the form of a depression in the cover, the depression having a constricted rim to grip the projection.

A problem experienced by the wearers of breathing masks is that changes of external air pressure lead to an imbalance in air pressure across the ear drum, and to discomfort for the wearer. Some way of equalising the air pressure is therefore needed and typically this is achieved by pinching the nose, clenching the lips and exerting pressure as by exhaling, a technique known as valsalva. In the case of a pilot or worker who is required to wear goggles, pinching the nose may not be practicable. The ability to pinch the nose effectively may also be restricted if thick gloves are being worn. A conventional breathing mask includes an outlet port provided with an expiratory valve which opens as the wearer exhales and through which the exhalate is vented. According to a second aspect of the invention, the port may be provided with a part which may be depressed by finger or thumb pressure to close the port. The cover may be so shaped by, for example, being dished, so as to allow the wearer to locate it with ease, even when wearing thick gloves. With the port closed, the wearer may exhale vigorously, and it is found that the effect of this is to equalise the pressure in the ear canals.

The first and second aspects of the invention need not be employed together, but either may be employed in a breathing mask without the other.

Embodiments of the above-mentioned aspects of the invention will now be described by way of example with reference to the accompanying drawings in which: -Figure 1 diagrammatically shows a mask embodying the first aspect of the invention, Figure 2 is an axial section through the fixing arrangement for the mask, and Figure 3 diagrammatically shows a mask embodying the second aspect.

Referring to Figure 1, a pilot is provided with an environmental protection hood 3 worn under a helmet 4. A breathing mask incorporates a face piece which is worn under the hood (and not visible in Figure i) and a cover 2 which is worn externally of the hood and is connected to the helmet by strapping, 5 and a bayonet fitting a which is retained in a receiver 5b attached to the helmet 4, as for example in GB 2313399. A hose 6 supplies air to the face piece of the mask.

The face piece is secured to the cover by an arrangement incorporating a stud 1 provided on the face piece and capable of inter-fitting with an opening 7 in the cover. The stud is of mushroom- like shape and has an enlarged head as shown in Figure 2 so as to be a snap- fit in the opening, with the material of the hood trapped between the stud and the cover. The stud may be readily snapped into the opening and released from it, but reliably secures the two parts of the mask is when interlocked with it.

Referring now to Figure 3, a breathing mask is provided with an expiratory valve having an outlet port 10 covered by a finger piece 9. The construction of the valve may be as described in UK Patent Application No. 0311338.8, but may alternatively be of any suitable known type. It is arranged to close as the wearer inhales, and to open as the wearer breathes out. When in its normal position the cover 9 does not interfere with this manner of operation but may be depressed to close the port 10 when it would normally be open.

In order to ease discomfort in the ears, the wearer of the mask may use the finger piece 9 to close the port and at the same time endeavour to exhale strongly.

Exhalation is prevented due to the port 10 being closed, resulting in elevated pressure in the wearer's respiratory system, thereby equalising or at least reducing the pressure difference across this ear drums. The wearer then releases the finger piece.

The finger piece may take the form of a cover for the outlet port retained by a central spigot ii and arranged to close the port when depressed. Alternatively -4..

the finger piece may be coupled to the valve and serve to over-ride and close it --when it would normally be open. The finger piece may be so shaped as to be easily identifiable by touch, as by being dished.

S Each feature disclosed in this specification (which term includes the claims) and/or shown in the drawings may be incorporated in the invention independently of other disclosed and/or illustrated features.

The text of the abstract filed herewith is repeated here as part of the

o specification.

A breathing mask has a face piece to be worn within a hood 3 and a cover 2 to be worn outside the hood, and a stud 1 for attaching the face piece to the hood. The stud is pressed into but not through the material of the hood, and both are retained in a clip formed in the cover 2 externally of the hood. According to a second aspect, a breathing mask has an outlet port capable of being closed by the wearer in order to allow him to equalise pressure in the ear canals.

The present disclosure also includes the following numbered clauses: 1. A breathing mask for use with a helmet and a hood worn within the helmet, the mask including a component for location within the hood and a component for location externally or the hood, one of the components being provided or associated with a projection capable of being pressed into the material of the hood, and the other component having an opening for receiving and retaining the projection and the portion of the hood to which it is applied.

2. A breathing mask as claimed in clause 1, wherein the projection has an enlarged head which is shaped to be retained in the opening.

3. A breathing mask as claimed in clause 2, wherein the opehing is defined by resilient material so that the projection is a snap-fit therein.

4. A breathing mask comprising a face piece to be worn within a hood and a cover to be worn externally of the hood and attachable to the helmet, the face piece being provided or associated with a stud with an enlarged head, the stud being retainable within an opening in the cover with a portion of the hood trapped between the stud.

and the cover.

Claims

Claims: 1. A breathing mask having an outlet port, a valve associated with the outlet port, the valve opening when a wearer of the mask exhales, and means operable by the wearer for closing the port when the wearer exhales.
2. A breathing mask as claimed in Claim I, wherein said means comprises a cover for the port, the cover being capable of being depressed or otherwise moved manually to close the port.
3. A breathing mask, as claimed in Claim 2, wherein the cover is so shaped as to be readily identifiable by touch.
4. A breathing mask having an outlet port capable of being closed by the wearer at will.
5. Breathing apparatus substantially as hereinbefore described with reference to and as illustrated in Figure 3 of the drawings.

5. Breathing apparatus substantially as hereinbefore described with reference to and as illustrated in Figure 3 of the drawings. *1

Amendments to the claims have been filed as follows Claims: 1. An aircrew breathing mask having an outlet port, a valve associated with the outlet port, the valve opening when a wearer of the mask exhales, and means operable by the wearer for closing the port when the wearer exhales to thereby facilitate pressure equalisat ion across the ear drums of the wearer.

2. A breathing mask as claimed in Claim 1, wherein said means comprises a cover for the port, the cover being capable of being depressed or otherwise moved manually to close the port.

3. A breathing mask, as claimed in Claim 2, wherein the cover is so shaped as to be readily identifiable by touch. 0)

4. An aircrew breathing mask having an outlet port capable of being closed by the wearer at will to facilitate pressure equalisation across the ear drums of the wearer.