GB2277433A - Aperture seal system for use in clothing and other wearable articles - Google Patents

Abstract

An inflatable controlled aperture seal system for use in, eg, survival suits, worksuits, artic clothing, fire-fighter's clothing, helmets and medical dressings and appliances. The system comprises an annular elastic tube (1) sealed to the wearable article and being inflatable and deflatable so that, upon deflation while wearing the article, the tube radially contracts to an extent sufficient to seal around a body portion of the wearer. Thus the system incorporates a fail-safe mode of operation in that, if failure of the system should occur, then the seal(s) will remain effective. The system also provides considerable advantages in comfort and ease of use. A preferred arrangement of a zip in a suit is described with reference to Fig. 7. Also, a manual air pump is described with reference to Fig. 8. <IMAGE>

Description

APERTURE SEAL SYSTEM FOR USE IN CLOTHING AND OTHER WEARABLE ARTICLES The present invention relates to wearable articles incorporating improved aperture seals. Such articles include any where a seal may need to be maintained permanently or temporarily around a body part of the wearer, such as, for example, survival suits (particularly those for which normal wear is also required), work-suits for dockside and waterside workers, arctic clothing, fire-fighters' clothing and helmets, dangerous sports clothing and helmets (e.g. for racing drivers), and medical dressings and appliances such as compression bandages, tourniquets and emergency splint systems for medical use.

The majority of cold water immersion survival suits currently in service depend for their safe performance on excluding penetration of the suit by substantially all external water. About 200ml of water entering the suit is the total amount normally permissable.

Although it is relatively simple to waterproof the fabric on construction, there has always been a serious problem with achieving an efficient seal at the neck, face, wrist and ankle apertures.

Currently, tight elastic latex seals are generally utilised. Such seals, although effective, have a number of limitations.

Firstly, they are extremely uncomfortable, particularly when not immersed in water, and due to this discomfort are often deliberately damaged to reduce tightness.

Secondly, if the size of the seal does not correspond to the body size of the user, the suit may either leak or be unbearably uncomfortable, and indeed in extreme cases may even restrict normal processes of swallowing and respiration. It must be remembered that most survival suits are provided to personnel on an emergency requirement basis and so sizing of the suit to the recipient is fairly random.

Thirdly, the closure of the apertures, particularly the neck aperture, increases the thermal strain on the user by preventing warm air and water vapour evacuating the suit in dry use.

Recent attempts to solve these problems have included the use of so-called inflatable cuff seals.

These cuffs, constructed from hollow latex rubber tubes, are inflated when required, to provide a seal at the aperture. This mechanism has certain advantages, as in the deflated mode it does not result in excessive discomfort. However, it still suffers from a number of limitations.

Firstly, there is a maintenance requirement. The seals and their inflation mechanism must be examined and tested regularly for performance. Even within a rigorous testing regime, there can be no guarantee that the cuff will inflate at the required moment.

Secondly, there is no guarantee that the cuff will stay inflated, particularly if accidental damage is likely, as in helicopter evacuation.

Thirdly, the inflated cuffs increases the buoyancy of the suit, and this is of major importance during helicopter evacuation.

All these factors relate directly to overall safety, and naturally some reluctance is inevitable to trusting one's life to a small inflated tube.

In view of recent marine accidents, where lives have been lost as a direct result of failure in performance of suit aperture seals, considerable effort is being dedicated to providing a practicable solution to these problems.

In view of the above state of the art, it is an object of the present invention to provide a fail-safe aperture seal system.

It is a further object of the invention to provide an aperture seal system which is potentially infinitely adjustable to accommodate different fit requirements of wearers of clothing and other wearable articles.

It is a further object of the invention to provide an aperture seal system in which the sealing function can be deactuated when not required.

To achieve these and other objects, the invention provides an aperture seal system for use in clothing and other wearable articles, the system comprising annular elastic tube means sealed to the wearable article to define the aperture, the tube means being inflatable and deflatable via valve means connected thereto so that, upon deflation while wearing the article, the tube means radially contracts to an extent sufficient to at least substantially seal around a body portion, e.g. a limb or neck, of the wearer.

The wearable article is preferably an overall having torso, arm and leg portions. The inflatable tube means according to the invention may advantageously be provided at each wrist and ankle as well as at the neck of the overall. The overall may have a hood portion, in which case the inflatable tube means may be provided around the face aperture of the hood. If desired, one or more apertures may be sealed via conventional sealing systems, provided that at least one aperture is sealed via the system of the present invention.

To achieve the maximum watertightness at an aperture, the overall should be constructed so that there are no zip or other fastener terminations at any of the apertures. Zip or other slide fasteners should preferably be provided diagonally across the torso portion of the overall, to allow it to be put on and taken off.

The valve means may be manually or automatically operable. Thus, for example, manually-operable valve means will allow the wearer to adjust the size of the apertures during normal wear; automatically operable valve means will suitably be arranged to open when required so that the aperture self-closes. For example, valve means arranged to open automatically on contact with salt water may be employed with aperture seal systems in a water-immersion survival suit. The tube means may, of course, be connected to both types of valve or to a combination valve which is actuable both manually and automatically.

The tube means are suitably inflated by a conventional pump or compressed gas (e.g. air or carbon dioxide) source, which may be external to, or incorporated within, the wearable article and operable by the wearer. The compressed gas source may, for example, comprise a small compressed gas storage container incorporated in the wearable article and connected to the valve(s) of the tube means. Pump means may suitably be hand-operable by the wearer and incorporated in the article, for pumping a gas or liquid to the tube means.

During normal wear and storage, the tube means at the apertures are suitably kept in a relatively inflated condition. The exact degree of inflation can be adjusted by the wearer using the manually actuated valve(s) and inflation means already mentioned.

The tube means are suitably constructed from a natural or synthetic rubber (e.g. latex rubber), as an annular tube sealed to the fabric of the wearable article via conventional waterproof bonding. An intermediate elastomeric membrane skirt or collar is preferably provided between the tube and the fabric of the wearable article to accommodate, by stretching and relaxing as the appropriate, variations in tube size on inflation and deflation. The skirt or collar is suitably sealed both to an envelope, which loosely retains the tube, and to the wearable article, by conventional waterproof bonding, e.g. via adhesives. The envelope is suitably annular and made of a similar rubber to that of the tube.

To achieve the necessary radial expansion/ contraction of the tube it is required that longitudinal expansion of the tube means is relatively favoured during inflation but that corresponding circumferential expansion of the tube transverse section is relatively disfavoured. Such a system can be arranged to maintain a strong grip on the body part of the wearer in the deflated condition and yet to relax its grip in the inflated condition. Such expansion/ contraction properties may suitably be achieved by providing relatively inelastic structures (e.g. fibres or integrally moulded portions) associated with the tube, which restrict or prevent expansion and/or contraction of the tube in directions other than the longitudinal direction.

In one preferred form, the tube means can be moulded, as well understood in rubber technology, in such a way as to favour longitudinal extension over radial expansion of the tube means.

In another preferred form, the tube means may have a fabric laminated thereto or located adjacent thereto as a sheath without substantial mutual bonding or lamination. The fabric has one predominant line of stretch, and is orientated so that this line of stretch corresponds at least approximately to the longitudinal direction of the tube means. By providing a fabric externally of the tube means, such a system can also improve wear comfort (where not further enclosed within a rubber envelope as described above) and can afford protection to the elastomeric material of the tube.

The tube should preferably undergo a longitudinal expansion of about 50% to about 200%, preferably about 100%, on inflation. The tube should preferably undergo a circumferential expansion in the transverse crosssection of 0% to about 50%, preferably about 10%, on inflation.

The aperture sealing system is constructed so that in the deflated condition the resting diameter is less than the body part of the wearer, so ensuring a tight grip in the deflated condition and an adequate waterproof seal for the survival suit.

Due to the elastic nature of natural and synthetic rubbers, relatively few sizes of aperture should be required, with one "normal" size being potentially able to accommodate all but the largest or smallest of each neck, face, wrist or ankle etc dimension, as the case may be.

For ease of understanding the invention, and to show how the same may be put into effect, embodiments will now be described, purely by way of example and without limitation, with reference to the accompanying drawings, in which: Figure 1 shows latex rubber tubes in longitudinal section, illustrating the difference between (a) circumferential and (b) longitudinal inflation of such tubes; Figure 2 shows such tubes in transverse section, illustrating the effect on the tube diameter, as between (a) the deflated and (b) inflated condition, of incorporating a bias towards longitudinal extension on inflation; Figure 3 shows schematically how the aperture seals of a survival suit are pneumatically operated; Figure 4 shows in detail the neck region of the survival suit of Figure 3; Figure 5 shows the neck region of the suit of Figure 3 in (a) a tube-inflated condition for normal wear and (b) a tube-deflated condition for wear in a survival situation;

Figure 6 shows schematically t details of the construction and attachment of (a) a first arrangement and (b) an alternative arrangement including an inflatable tube, to the fabric of the suit of Figure 3; Figure 7 shows alternative zip arrangements for the suit of Figure 3, with the zip located across (a) the back and (b) the front of a torso portion of the suit; and Figure 8 shows in cross-section details of the manual pump system for the suit of Figure 3.

Referring to the drawings, an endless latex rubber tube 1 forms a ring sealed in waterproof manner into the neck portion of a survival suit 2 of generally conventional construction.

The tube 1 is sealed to the fabric of the suit 2 via an intermediate elastic (e.g. latex) rubber membrane skirt or collar 3.

In a first possible arrangement, shown in Figure 6(a), the elastic skirt 3 is sealed both to the tube 1 and the suit 2 fabric by conventional waterproof bonding. The bonding to the tube may be by adhesive or by integral moulding with the tube; the bonding to the fabric may be by adhesive.

In a second possible arrangement, shown in Figure 6(b), the elastic skirt 3 is sealed to the suit 2 fabric by conventional waterproof bonding and carries an annular envelope portion 3a which encircles the tube 1 loosely

and includes an aperture to allow 8 (described in more detail below) to pass through the envelope wall.

The tube 1 is moulded (Figure 6(a) or, more preferably, provided with an external sheath 1A of a oneway stretch fabric which is not laminated or otherwise substantially bonded to the tube 1 (Figure 6(b)), so that longitudinal extension of the tube (illustrated schematically by arrows A in the case of a straight tube 4 in Figure l(b)) is favoured over circumferential expansion of the tube walls (illustrated schematically by arrows B in the case of a straight tube 5 in Figure l(a)). In Figure 1 the solid lines illustrate a relatively inflated condition of the tube wall, while the dotted lines illustrate a relatively deflated condition.

The stretch direction of the fabric of the external sheath la of Figure 6(b) is aligned in the longitudinal direction of the tube 1.

The effect of such construction on the inflation properties of an endless annular tube 1 of the rubber material is illustrated in Figure 2. In the deflated condition shown in Figure 2(a) the tube walls are relatively thick, whereas in the inflated condition shown in Figure 2(b) the tube walls are thinner, with the transverse sectional diameter of the tube 1 slightly increased. However, the radial diameter of the annulus formed by the tube increases significantly on inflation, as shown in more detail in Figure 4.

Referring now particularly to Figures 3 to 5, a wearer's neck 6 protrudes trough an aperture of the survival suit 2 provided with a seal arrangement in accordance with the invention. The wearer's limbs protrude through apertures of the arms and legs of the suit, provided with corresponding seal arrangements.

The suit is initially put on with each tube 1 inflated. Inflation is achieved via a small manually operable pump 7 incorporated into the suit 2 under the outer surface thereof, and connected to each tube by a small air line 8 under the outer surface of the suit 2.

For ease of illustration, the pneumatic system is shown in Figure 3 without the outer portion of the suit, which in reality shields and protects the pneumatic system.

Inflation of the tube 1 can either be carried out immediately prior to putting the suit on, or the tube can be kept for extended periods of time in an inflated condition. The inflated tubes widen the apertures of the suit considerably, and facilitate putting the suit on, especially in an emergency.

During normal wear each tube 1 is typically kept inflated, although partial deflation to the condition shown in Figure 4 may take place if it is desired to partially close the apertures of the suit, e.g. to control ventilation of the suit. So long as a gap is left between the suit and the wearer's neck, for example, the interior of the suit will remain well ventilated and warm most air will rise up and evacuate the suit. A relatively high degree of comfort and user acceptability can be achieved, even in prolonged dry use, to the level expected for constant-wear survival and work suits.

If, during normal use, the tubes slowly deflate through air leakage, or if the wearer wishes to open the apertures of the suit further, the wearer can simply reinflate the tubes via the pump 7.

Referring particularly to Figures 3 and 8, the pump 7 comprises a rubber bulb 9 which constitutes an air reservoir for the pump. The bulb 9 is arranged to be evacuated by hand compression.

The pump 7 is connected to the neck and limb aperture sealing systems of the suit via the branched system of air lines 8.

To inflate the tubes 1, a conventional screwoperated control valve 10 associated with exhaust port 11 is first closed to close the port, and the bulb 9 is manually compressed. Air is thereby pumped through a conventional non-return valve 12 into air line 8, and thence into the tubes 1 of the aperture sealing system.

Upon release of the manual compression of the bulb 9, the bulb expands elastically and is replenished with air through a conventional ball valve 13, non-return valve 12 preventing air from returning to the bulb from the air lines. The pumping operation can then be repeated if desired.

To deflate the tubes 1, the system is evacuated by manually opening the control valve 10. In an alternative system (not shown) the control valve 10 may be automatically openable when a defined survival situation (e.g. water immersion) is encountered by the wearer, by means of a conventional automatic override actuated in response to signals provided by sensors (e.g. salt water sensors) in the suit.

All parts of the pneumatic system are suitably constructed from non-corrodible materials such as natural or synthetic rubbers, plastics, brass or stainless steel.

The annular diameter of each tube reduces on deflation and grips the wearer's neck 6 and limbs, as shown in Figure 5(b), by virtue of the fact that the minimum deflated annular diameter is selected to be less than the diameter of the wearer's neck or limb, as the case may be. Thus, in the deflated condition of the tube 1 a waterproof seal is achieved around the wearer's neck for limb, as the case may be, and the tightness of this seal can be adjusted by the wearer whilst in the water, via pump 7.

The system is fail-safe, in that failure (deflation) of the seal in the event of a puncture of the tube 1 or leakage of valve 10 will still result in an effective aperture seal in a survival situation. This is a prime advantage of the present invention.

Furthermore, the wearer will become aware of (and hence be able to cure) any leaks prior to donning the suit, or during normal use, and not after the survival situation has commenced.

Referring finally to Figure 7 in particular, alternative preferred zip or slide fastener arrangements for the suit are illustrated in Figures 7(a) and Figure 7(b). It is important that zip or slide fasteners do not interfere with, or terminate at, any of the apertures, or the seal action of the apertures can be compromised. In the arrangement shown in Figure 7(a) a zip fastener 14 extends across the shoulder part of the back side of the torso portion of the suit 2. In the arrangement shown in Figure 7(b) which is the more preferred, a zip fastener 14 extends diagonally across the front side of the torso portion of the suit 2 from one shoulder to the opposite hip.

Without intending to limit the potential applications of this invention in any way, the following examples of possible uses of the aperture seal system may be particularly mentioned: Clothing 1. All types of constant-wear and abandonment survival suits; 2. Dockside/waterside work suits; 3. Arctic exploration clothing systems; 4. Fire-fighting clothing systems; 5. Fire fighting helmet systems; 6. Racing-drivers' helmets, to provide a fireproof membrane between the helmet and neck (may be activated with a built-in oxygen or air supply).

Medical 1. Post-traumatic emergency compression bandage; 2. Variable pressure tourniquet; 3. Temporary/emergency splint systems.

The foregoing broadly describes the invention without limitation to any particular embodiment.

Variations and modifications as will be readily apparent to those skilled in this art are intended to be encompassed within the invention.

Claims (18)

1. An aperture seal system for use in clothing and other wearable articles, the system comprising annular elastic tube means sealed to the wearable article to define the aperture, the tube means being inflatable and deflatable via valve means connected thereto so that, upon deflation while wearing the article, the tube means radially contracts to an extent sufficient to at least substantially seal around a body portion of the wearer.

2. An aperture seal system according to Claim 1, wherein the said annular elastic tube means comprises a closed endless annular tube.

3. An aperture seal system according to Claim 1 or Claim 2 wherein the tube means is adapted so that longitudinal expansion thereof on inflation is relatively favoured, compared with corresponding circumferential expansion thereof, which is relatively disfavoured.

4. An aperture seal system according to Claim 3, wherein the tube means includes relatively inelastic structures associated with the tube means, which restrict or prevent expansion and/or contraction of the tube in directions other than the longitudinal direction of the tube means.

5. An aperture seal system according to Claim 4, wherein the tube means includes portions integrally moulded therewith, which restrict or prevent expansion and/or contraction of the tube in directions other than the longitudinal direction of the tube means.

6. An aperture seal system according to Claim 4, wherein the tube means has associated therewith a fabric which has one predominant line of stretch, the fabric being orientated so that such a line of stretch corresponds at least approximately to the longitudinal direction of the tube means.

7. An aperture seal system according to claim 6, wherein the fabric comprises an external fabric sheath for the tube means.

8. An aperture seal system according to any one of the preceding claims, wherein the tube is adapted to undergo a longitudinal expansion of about 50% to about 100% and a circumferential expansion of 0% to about 50%, on inflation.

9. A wearable article having portions defining an aperture to receive a part of a wearer's body, the article including an aperture seal system for said aperture comprising annular elastic tube means sealed to the said aperture-defining portions, the tube means being inflatable and deflatable via valve means connected thereto so that, upon deflation while wearing the article, the tube means radially contracts to an extent sufficient to at least substantially seal around the body portion of the wearer.

10. A wearable article according to Claim 9, when in the form of a survival suit including an overall having torso, arm and leg portions, the said elastic tube means being provided at one or more of wrist, ankle and neck apertures of the overall.

11. A wearable article according to Claim 10, wherein pump means for inflating the tube means are provided to be manually operable by the wearer, the pump means being connected to the tube means via said valve means.

12. A wearable article according to Claim 10, wherein a single pump is provided for supplying fluid to all tube means present in the survival suit.

13. A wearable article according to Claim 11 or Claim 12, wherein some or all of the tube means present in the survival suit are connected to each other via fluid lines and to the pump means, and control valve means are provided associated with the fluid lines, whereby one tube means can be deflated simultaneously with some or all of the or any other(s) to activate the aperture sealing system.

14. A wearable article according to Claim 13, wherein further valve means are provided associated with the fluid lines, whereby one tube means can be deflated independently of any other(s), if desired by the wearer.

15. A wearable article according to Claim 9, when in the form of a helmet, the said elastic tube means being provided at neck and, if present, face apertures of the helmet.

16. A wearable article according to Claim 9, when in the form of a medical dressing or appliance.

17. An aperture seal system substantially as herein described, with reference to Figures 1, 2 and 6(a) or 6(b) of the accompanying drawings.

18. A wearable article substantially as herein described, with reference to Figures 1, 2, 4 and 5 of the accompanying drawings optionally with further reference to Figure(s) 3 and/or 6(aj and/or 6(b) and/or 7(a) and/or 7(b) thereof.