GB2047545A

GB2047545A - Respirators

Info

Publication number: GB2047545A
Application number: GB7847779A
Authority: GB
Original assignee: UK Secretary of State for Defence
Current assignee: UK Secretary of State for Defence
Priority date: 1977-12-09
Filing date: 1978-12-08
Publication date: 1980-12-03
Also published as: GB2047545B

Abstract

A respirator of the type used by aircrew comprises a hood 20 and visor 21 combination adapted to envelop the head of the user, a breathing mask 22 carried in the visor, and means which enable the user to unblock his ears during change of altitude by occluding his nose. The noise occlusion means comprises a pair of impingement members 10, preferably of spheroidal surface, and a sling formed of reticulated fabric, and is arranged so that the sling will, under pressure from the nasal septum, bring the impingement members 10 to bear on the user's nose lobes when the visor 21 is pushed up along the user's face. <IMAGE>

Description

SPECIFICATION Improvement in a relating to respirators The present invention relates to headgear to be worn by personnel for protection against unpleasant or toxic substances in their local atmosphere, such as radioactive, chemical and/or bacterial substances. As it is fundamental to such headgear that safe breathing supplies are maintained, headgear in accordance with the invention are hereinafter called respirators.

Co-pending UK patent application No 20135/76 describes a respirator for protection against undesirable substances in a local atmosphere and which comprises a hood and a visor both made of material impervious to the undesirable substance, attached one to another in a manner impervious to the undesirable substance and adapted to fit and envelop closely the head of a wearer, means for permiting a wearer to breathe acceptable air and/or oxygen, means for maintaining a gas pressure within the respirator greater than local environmental pressure, and seal means for preventing atmosphere outside thereof from reaching the interior of the respiratory via the neck aperture thereof.

The primary utility of such respirators is in the protection of aircrew, particularly military aircrew, and it is a feature of that invention, and indeed of the invention the subject of the co-pending patent application 44022/78 Serial No. 2045090 that such respirators may be used at all altitudes. Now a significant proportion of aircrew find it necessary to occlude their noses to unblock their ears during change of altitude. The present invention provides in a respirator of the type described in co-pending patent application No 20135/76 means whereby a user may occlude his nose.

According to the present invention, a respirator of the type comprising a hood and visor combination for closely enveloping the head of a user and an oronasal mask contained or formed within the hood for delivering breathable gas to the user's nose and mouth has manually operable nose occlusion means comprising within the mask a pair of nose impingement members operable in use to pinch together onto the sides of a user's nose, and nose operable lever means for operating the impingement members, the arrangement being such that in use the user may move his respirator in relation to his face to obtain operation of the nose occlusion means.

According to a feature of the invention spring means may be included for restoring the occlusion means to a non-impingement configuration. Alternatively natural resilience of the user's nose or of the respirator mask, especially is the latter is formed of a rubber, may be relied upon for relaxation of the occlusion means.

According to another feature of the invention the lever means may comprise a sling.

The sling may be formed of a woven or nonwoven fibre fabric, of plastics film fabric, or of one reinforced with the other. As it is preferred, however, that the sling extends across the nasal septum, it may be formed of a fabric so reticulated as neither significantly to block the nostrils against normal breathing nor painfully to press against highly localised regions of the nose when in use. The sling is preferably detachably attached to the impingement members so that it can be replaced.

In embodiments where the lever means is arranged for operation by the nasal septum it will be appreciated that this operation can be obtained by moving the mask or visor member upwards parallel to the user's face.

Each impingement member preferably has a spheroidal impingement surface and may comprise a ball or part thereof.

In respirators wherein the visor is an exoskeleton adapted to cover substantially the whole of a user's face and supports the mask the occlusion means may usefully be mounted in the visor. To cater for variations in the shape of the human face the occlusion means have an adjustable mounting such as for example extensible arm members or members which can readily be bent by the user to a preferred configuration during initial fitting of the respirator.

Apparatus according to the present invention will now be described by way of example with reference to the accompaiiying drawings of which: Figure 1 is a general arrangement of a nose occlusion device, and Figure 2 illustrates the mount of that device in a respirator.

The nose occlusion device shown in Fig. 1 has a pair of nose impingement members 10 pivotally attached one to the extremity of each arm of an extensible bracket 11. Springs 1 2 urge the members 10 outwards. A sling 1 3 extends between edges of the members 10 remote from the pivot attachment. The sling is made of reticulated man made fibre fabric.

The nose impingement members 10 have spherical impingement surfaces and are mounted so that these surfaces face one another in use. The bracket 11 is made of metal sheet material which may readily be bent to vary the symmetry of the device and the degree of projection thereof from its mounting.

The device is mounted, as shewn in Fig. 2, within a respirator of the type comprising a close fiting hood cowl 20, an exoskeleton forming a face visor 21, and an oronasal mask 22. The bracket 11 is adapted to be attached to the respirator at attachment points for the mask to the exoskeleton.

With the device so mounted within a respirator.a user will, before donning the respirator check the configuration of the device. The desired configuration is that normally with the respirator fully donned the sling 1 3 comfortably underlies the nasal septum, yet that upward movement of the respirator parallel to the user's face which will be permitted by the shape thereof and the constraints imposed by a flying helmet will be sufficient for the nasal septum to bear on the sling and for the latter to pull the impingement members 10 inwards to pinch the nose in that fleshy region just above the nostril orifices and to occlude the orifices.

Thus, when an aircrewman wearing an enveloping respirator desires to unblock his ears by occluding his nose, for example as a result of changing altitude, he may do so by pushing his respirator up his face, perhaps first rocking his helmet back somewhat in order to maximise the movement freedom of the respirator.

Claims

1. A respirator of the type comprising a hood and visor combination for closely enveloping the head of a user and an oronasal mask contained or formed within the hood for delivering hreathable gas to the user's nose and mouth having manually operable nose occlusion means comprising within the mask a pair of nose impingement members operable in use to pinch together onto the sides of a user's nose, and nose operable lever means for operating the impingement members, the arrangement being such that in use the user may move his respirator in relation to his face to obtain operation of the nose occlusion means.

2. A respirator as claimed in claim 1 and having spring means for restoring the occlusion means to a non-impingement configuration.

3. A respirator as claimed in claim 1 or claim 2 and wherein the lever means comprises a sling.

4. A respirator as claimed in claim 3 and wherein the sling is formed of a fabric so reticulated as neither significantly to block the nostrils against normal breathing nor painfully to press against highly localised regions of the nose when in use.

5. A respirator as claimed in claim 3 or claim 4 and wherein the sling is detachably attached to the impingement members so that it can be replaced.

6. A respirator as claimed in any one of claims 1 to 5 and wherein the lever means is operable by the nasal septum, this operation being obtainable by moving the mask or visor member upwards parallel to the user's face.

7. A respirator as claimed in any one of the preceding claims and wherein each impingement member has a spheroidal impingement surface.

8. A respirator as claimed in any one of the preceding claims, and wherein the visor is an exoskeleton adapted to cover substantially the whole of a user's face and supports the mask and the occlusion means is mounted on the visor.

9. A respirator as claimed in any one of the preceding claims and wherein the occlusion means have an adjustable mounting.

1 0. A respirator substantially as hereinbefore described with reference to the accompanying drawings.