EP0371858B1 - Individual respiratory and contamined environment protective equipment - Google Patents

Description

The subject of the invention is personal protective equipment in an environment likely to present contamination of nuclear, biological or chemical origin, so-called NBC protective equipment.

It relates more particularly to individual respiratory and protective equipment comprising an oro-nasal respiratory mask provided with a conduit for connection to an external source of respiratory gas, a helmet having a rigid shell and detachable padding and a hood provided with a visor, intended to separate the head from the atmosphere and provided with ventilation air supply means.

There are already various individual pieces of equipment of the type defined above intended for crew members of aircraft capable of operating at high altitude, which requires the wearing of a respiratory mask supplied by an external source of oxygen-enriched mixture or even of pure oxygen.

For reasons of comfort, personnel should only be equipped with an NBC protective hood for missions where it may become necessary. Consequently, the use of an inseparable set of hood-respiratory mask (US-A-4 404 969) is not acceptable in practice: it leads to the provision of two separate complete pieces of equipment.

Two types of hood independent of the mask and helmet are used today.

A first type of hood is provided to be donned by the wearer of the equipment over the helmet and the mask. This solution makes it possible to ventilate without difficulty the interior of the hood and reduces the discomfort it brings (EP-A-0 153 247). But in return, this solution has drawbacks: The wearer's downward field of vision is greatly reduced by the size of the bulge in the hood necessary to wrap both the mask and the entire helmet. No device can be fixed directly to the helmet shell, which notably prohibits the use of a helmet visor. The wearer no longer has access to the mask attachment harness and can no longer adjust it.

The second type of hood currently used is intended to be put directly on the head, in contact with the skin. This solution makes it difficult to ventilate the hood and demist the visor by circulating fresh air. Wearing the hood is very uncomfortable. The hood does not protect the helmet from contamination. However, if the rigid shell is easily decontaminated, it is not the same for the padding and the elements that it carries, such as the headphones of the communication system, and the pocket (or pockets) intended to be put in overpressure at very high altitude.

The present invention aims to provide individual equipment of the above defined type which better meets the requirements of the practice than those previously known; more particularly, it aims to provide equipment which can be used with or without a hood, the use of which with a hood only results in reduced discomfort; for this purpose, the invention proposes in particular an equipment characterized in that the padding and the shell of the helmet are provided so as to be able to adapt to one another as well directly as through the hood interposed between them and in that the hood is provided with means for sealingly crossing the connection conduit.

The hood is advantageously provided with a ventilation gas supply duct connected to a ramp visor defogging. In the padding of the helmet can then be provided ventilation channels opening facing the ramp so as to be supplied by the latter when the equipment is worn with the hood.

It is desirable that the mask is directly attached to the shell of the helmet to avoid untimely movements, especially during sudden changes. To allow this fixing, the hood is advantageously provided with means for crossing the mask fasteners on the shell which does not make the seal disappear. These crossing means may in particular be constituted by means of local attachment of the hood on the mask and on the straps or connecting rods on the helmet in an adjustable position.

It can be seen that, in such equipment, the hood prevents contamination of the padding, of the elements which it wears and of the mask. Only the rigid shell and its visor (s) must be decontaminated after a mission, which does not raise any serious problem.

The invention will be better understood on reading the following description of a particular embodiment, given by way of non-limiting example.

• la figure 1 montre schématiquement un équipement de protection, destiné à un pilote d'avion de combat ;
• les figures 2, 3, 4 et 5 sont des vues en élévation montrant respectivement la coque et le rembourrage du casque de la figure 1, la cagoule et le masque ;
• la figure 6 est une vue en perspective du rembourrage de la figure 3, destinée à mieux faire apparaître certains de ses constituants.

The description refers to the accompanying drawings, in which:

• FIG. 1 schematically shows protective equipment, intended for a pilot of a combat aircraft;
• Figures 2, 3, 4 and 5 are elevational views respectively showing the shell and the padding of the helmet of Figure 1, the hood and the mask;
• Figure 6 is a perspective view of the padding of Figure 3, intended to better show some of its constituents.

The respiratory equipment shown schematically in Figures 1 to 6 includes a helmet consisting of a shell 10 and padding 12. The shell 10 carries receptacles 14 intended to receive the fasteners 16 for fixing a respiratory mask 18, the constitution of which may be conventional. Finally, the equipment includes a hood 20, used or not depending on the type of mission. These various components will be successively described.

The shell 10 of the helmet is made of rigid molded material. It can have one of the constitutions known at present. In the embodiment shown in Figures 1 and 2, this shell is provided with two movable visors 22, by tilting around axes 24, between a retracted position (Figure 2) and a position where it comes to bear against the mask 18 (Figure 1). In the case shown in FIG. 2, the visors retract in a clearance arranged between two walls of the shell 10. But the visors might as well be folded over a simple shell.

The padding 12 must be provided so that it can be mounted in the shell 10, either directly or through the hood 20, and remain integral with the shell when all of the equipment is in place. In particular, the padding and / or the shell may be provided with adhesive strips of the type known under the brand "Velcro". One can also use other solutions allowing temporary hanging, for example snaps. The padding 12 carries, conventionally, the headphones 26 of the communication system with the wearer. In the embodiment illustrated in FIG. 2, pockets provided around the earphones allow an ear protection overpressure to be established in the event of external depressurization, as described in document US-A-4,172,455. These pockets extend behind the padding to form a pocket capable of being pressurized by admission of pressurized gas through a line 28 to press the mask against the face and avoid detachment when the wearer of the equipment is supplied with overpressure respiratory gas. A cable 30 terminated by a connector 32 allows the power supply to the headphones 26 (FIG. 6).

In the external face of the padding 12 shown in FIGS. 3 and 6, ventilation channels 34 are formed, whose role and operation will appear below.

The mask 18 (FIG. 5) conventionally comprises a semi-rigid shell intended to cover the nose and the mouth, provided with fasteners which may have, for example, the constitution described in patent application FR-88 04616 of the applicant. To the shell is fixed a pipe 35 for supplying the respiratory gas, terminated by a connector 36. This pipe is for example connected, when the equipment is used, to a regulator, according to an arrangement which may be that described in the document EP-A-0 153 247 already mentioned. The fasteners 16 are connected to the shell of the helmet by detachable fasteners, allowing the hood to be inserted.

The hood 20 (Figures 1 and 4) is intended to wrap the head, the padding 12 with its accessories and the mask 18 while allowing the watertight exit of the various necessary connections.

This hood 20, made of flexible and waterproof material such as vinyl, has a shape which fits on the padding 12 and the mask 18. Several sizes of hoods can be provided to adapt to different helmets. The hood generally has a folded collar 38 (Figure 4) applying to the neck, the role of which is to reduce gas leaks from the inside of the hood and to prevent leaks from the outside.

The hood is equipped with a transparent visor 40 fixed in a sealed manner at the edge of an opening made in the part of the hood which is made of flexible and opaque material. It is desirable that the visor be as close to the eyes as possible and allow for extended downward vision. For this, as shown in Figure 4, the visor has a flange 42 glued under the edges of the opening.

The hood must be maintained by ventilation at slight pressure compared to the ambient atmosphere to prevent the entry of contaminants. In addition, it is desirable to sweep the visor with a flow of air to avoid the formation of fogging interfering with vision. The two results are achieved by providing the hood with an internal demister ramp 44 (FIG. 4) placed against the upper part of the rim of the hood visor and connected to a pipe 46 for supplying filtered air. The ramp is pierced with holes which direct an air flow over the interior of the visor, as indicated by arrows in FIG. 4. The pipe 46 can in particular be supplied with filtered air by a device of the type described in the document. EP-A-0 153 247 already mentioned.

When channels 34 are provided in the padding (FIGS. 3 and 6), ventilation air outlet orifices are advantageously drilled in the ramp 44 opposite these channels, to create cooling ventilation for the scalp.

The hood must be fitted with means for substantially sealing the passage 35 for supplying respiratory gas to the mask. In the case illustrated in FIGS. 1 and 4, these means consist of a sheath 48 in one piece with the hood, of diameter at rest such that it is applied in a substantially sealed manner on the supply pipe 35 (figure 1).

The hood 20 is also equipped with substantially leaktight crossing means making it possible to fix the fasteners 16 to the shell of the mask 18. A first solution consists in providing the hood with a through nipple 50 (FIG. 4) which can be hooked on the mask and receive the attachment point of the fastener 16. Another solution is to provide an annular crossing seal. In all cases, it remains possible to fix the clip on the mask shell, either directly or through the hood 20.

A separate passage can be provided for the output cable 52 of the microphone equipping the mask 18. Another solution consists in providing the sheath 48 to allow the simultaneous exit of the pipe 35 and the cable 52.

A calibrated valve 54 will generally be provided on the hood to limit the overpressure that prevails inside and evacuate the exhalation gases and the filtered ventilation air. It will be advantageous to provide the hood with temporary fixing means on the shell 10 and on the padding 12: these means will be chosen according to those which, in the absence of the hood, allow the padding to be fixed directly to the helmet.

Such a constitution of the equipment makes it possible to use it with and without a hood, without the use of the hood significantly complicating the dressing: when the hood is to be used, the mask 18 and the padding 12 are first placed inside the hood 20. The connections with the outside are made. The wearer can then don the hood-mask assembly. The shell 10 of the helmet is placed last over all, and the mask can be hung on the receptacles 14 of the shell without difficulty.

In practice, a very small number of hood sizes, and sometimes even a single size, suffices, provided you have padding of several sizes. Similarly, it will generally suffice for three shell sizes to meet all of the requirements.

We see that the equipment described allows, by using only simple means, use in NBC conditions as well as in normal conditions, bringing only reduced discomfort to the user and without the need for duplication equipment.

Claims (6)

1. An individual breathing and protective apparatus in a contaminated environment, comprising a breathing mask (18) for nose and mouth, fitted with a duct (35) for connecting to an external source of respiratory gas, a helmet having a rigid shell (10̸) and detachable padding (12), and a hood (20̸) with a visor, together with means for supplying air for ventilation,
   characterised in that the padding (12) and the shell (10̸) are adapted to fit in one another, either directly or via the hood (20̸) inserted between them, and the hood (20̸) has sealing-tight lead-in means (48) for the connecting duct (35).
2. Apparatus according to claim 1, characterised in that the hood has lead-in means (50̸) for the securing tips of fasteners (16) of the mask on to the helmet.
3. Apparatus according to claim 1 or 2, characterised in that the sealing-tight lead-in means (48) comprise a bush in one piece with the hood.
4. Apparatus according to claim 1, 2 or 3, characterised in that the hood has a duct (46) for supplying ventilation gas and connected to a manifold for demisting the hood visor.
5. Apparatus according to claim 4, characterised in that ventilation channels (34) are formed in the padding and open opposite the manifold.
6. Apparatus according to any of the preceding claims, characterised in that the padding (12) and/or the shell (10̸) have means for temporarily securing one to the other.

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