GB1576765A

GB1576765A - Buoyancy aid

Info

Publication number: GB1576765A
Application number: GB3353977A
Authority: GB
Original assignee: CROMPTON A D Ltd; Crompton Ltd
Current assignee: CROMPTON A D Ltd; Crompton Ltd
Priority date: 1978-05-19
Filing date: 1978-05-19
Publication date: 1980-10-15

Description

(54) AN IMPROVED BUOYANCY AID (71) We, A. D. CROMPTON LIMITED, a British Company of Sovereign Street Salford, M6 6PJ, Lancashire, do hereby declare the invention, for which we pray that a Patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The invention concerns buoyancy aids, and has more particular reference to jacket-type buoyancy aids and the like.

Buoyancy aids of the kind to which the invention relates are known which comprise inner and outer plies of a reinforced platics material, for example, a polyvinyl chloride sheet material such as that sold under the Trade Mark "WAVELOCK", between which are located insert members comprising shaped blocks of a synthetic plastics foam disposed within a sheath of water-impermeable sheet plastics material, the sheaths being shaped to conform to the relevant panel of the garment and containing one or more such blocks. Each sheath is itself formed from superimposed plies of polyvinyl chloride sheet material, the plies being joined about their edges by high-frequency welding, and in the event that more than one foam block is included, the plies are additionally joined, again by high-frequency welding, between the individual blocks.

Whilst buoyancy aids having insert members as aforesaid have met with widespread acceptance, such aids do give rise to various problems. For example, in addition to the discomfort arising from the rigidity of the insert members, the extent to which the buoyancy is adversely affected on rupture of a sheath is significant, and can, in some instances, be such as to endanger the life of the wearer, even though the reduction in buoyancy is not such as to result in a buoyancy inadequate to support the wearer. Thus, for example, failure of an insert member or part thereof in the front of the garment may destroy the inherent ability of such garment to turn a wearer onto his back thus to keep his face out of the water, with obvious consequences especialy if the wearer is unconscious in the water.

The primary object of the present invention is to provide an improved buoyancy aid wherein the adverse effect on buoyancy in the event of sheath rupture from whatever cause is minimal.

A further object of the invention is to provide a buoyancy aid which allows of a greater freedom of movement and gives rise to less discomfort in wear than conventional such aids.

According to the invention there is proposed a buoyancy aid comprising inner and outer plies shaped to define a garment and a buoyancy means disposed between such plies, characterised in that the buoyancy means comprises a plurality of individual buoyancy sachets in each garment panel, each such sachet including a block of foamed synthetic plastics material and a water impermeable covering thereto, and the buoyancy of each sachet is less than one pound.

The sachets may be separate from one another, or a plurality thereof may be provided in joined edge-to-edge disposition.

In this latter case the individual sachets are separable as complete units without adversely affecting the integrity of the adjacent sachets.

The invention also includes a sachet for use as aforesaid.

The invention will now be described further, by way of example only with reference to the accompanying drawings illustrating one embodiment thereof and in which: - Fig. 1 is a diagrammatic perspective view, partly broken away, of a buoyancy aid having a buoyancy means in accordance with the invention; and Fig. 2 is a broken perspective view, drawn to a larger scale of the sachet of the invention.

Referring now to the drawing, a buoyancy garment comprises inner and outer plies 11, 12 of a reinforced, polyvinyl chloride sheet material, for example, such as that sold under the Trade Mark "WAVELOCK", having buoyancy material receiving pockets 13, 14 as defined by lines of weld 15 joining the inner and outer plies. Th lower edges of the pockets 13, 14 are closed after positioning of the buoyancy material by joining the plies, as by welding, and an edging tape 16 is applied.

In contradistinction to the prior art, wherein the buoyancy means comprises a block or blocks of a synthetic plastics foam material provided within a common closed 'sheath of air impermeable plastics sheet material, the blocks being shaped and dimensioned according to the shape and dimensions of the panel to which the same are to be applied, in accordance with the invention the buoyancy material is provided in the form of individual sachets 17 of a constant predetermined size and in a number appropriate to the shape and dimensions of the respective pockets 13, 14.

Each sachet 17 comprises a block 17cur of foamed, synthetic plastics material disposed within a repsective envelope 17b, such envelope being formed by superimposed plies of suitable material, which plies are joined about the periphery of the block as by high freqnency welding. The block comprises an open cell polyurethane foam of rectangular form five inches long, three inches wide and approximately on one and a quarter inches thick, whilst the envelope is formed from air and water impermeable sheet polyvinyl chloride material eight thousandths of an inch thick. Alternatively, the envelope may be formed from reinforced plastics sheet material, for example, that sold under the Trade Mark WAVELOCK", of an equivalent performance. Other foamed plastics materials, whether of open or closed cell form, may be used.The welding together of the superimposed plies of sheet polyvinyl chloride or alternative material will preferably be so effected that the corners are radiussed.

The number and distribution of the sachets will vary according to the dimensions and shape of the pocket concerned, a typical arrangement being as shown in Fig.

1 of the drawing.

By using a sachet of the size hereinproposed we are able to achieve a buoyancy appropriate to the garment concerned in a ready manner by selection of the appropriate number and distribution of sachets and, more importantly, are able accurately to determine and to obtain a requisite buoyancy in any particular instance. The buoyancy derivable from a single sachet, being less than llb. buoyancy (preferably 0.71bs. buoyancy), has been found to lend itself readily to utilisation in a range of garment sizes accurately to give a buoyancy appropriate to the garment according to the number of sachets utilised.

By providing individual sachets each complete in itself, the extent to which buoyancy is reduced on rupture of a sachet is limited to the buoyancy derived from such sachet, which buoyancy is relatively small. In the case of conventional arrangements, rupture of a sheath may well result in the loss of buoyancy attributable to the block or all of the blocks within that sheath. If the blocks of the prior arrangements are separated by weld lines, then a rupture in the region of such separating weld line will result in the loss of buoyancy of the whole sheath in exactly the same way that such buoyancy will be lost if there are no separating weld lines.

The provision of multiple sachets as hereinproposed will reduce the restriction imposed on movement of the wearer, and will result in a more comfortable garment.

While we have described the invention in the context of individual and separate sachets, the invention is not limited to the use of such sachets. For example, the sachets may be provided and used in multiple units subject to the proviso that adjacent sachets are separable as a whole.

WHAT WE CLAIM IS: - 1. A buoyancy aid comprising inner and outer plies shaped to define a garment, and a buoyancy means disposed between such plies, characterised in that the buoyancy means comprises a plurality of individual buoyancy sachets in each garment panel, each such sachet including a block of foamed synthetic plastics material and a water-impermeable covering thereto, and the buoyancy of each sachet is less than one pound.

2. A buoyancy aid as claimed in claim 1, wherein the buoyancy of each sachet is approximately 0.7 pounds.

3. A buoyancy aid as claimed in claim 1 or claim 2, wherein the sachets are provided as individual and separate elements in the garment.

4. A buoyancy aid as claimed in claim 1 or claim 2, wherein some at least, of the sachets are provided as multiple units each separable from another as a complete sachet.

5. A buoyancy aid as claimed in any one of the preceding claims, wherein the block of foamed synthetic plastics material com

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. aid having a buoyancy means in accordance with the invention; and Fig. 2 is a broken perspective view, drawn to a larger scale of the sachet of the invention. Referring now to the drawing, a buoyancy garment comprises inner and outer plies 11, 12 of a reinforced, polyvinyl chloride sheet material, for example, such as that sold under the Trade Mark "WAVELOCK", having buoyancy material receiving pockets 13, 14 as defined by lines of weld 15 joining the inner and outer plies. Th lower edges of the pockets 13, 14 are closed after positioning of the buoyancy material by joining the plies, as by welding, and an edging tape 16 is applied. In contradistinction to the prior art, wherein the buoyancy means comprises a block or blocks of a synthetic plastics foam material provided within a common closed 'sheath of air impermeable plastics sheet material, the blocks being shaped and dimensioned according to the shape and dimensions of the panel to which the same are to be applied, in accordance with the invention the buoyancy material is provided in the form of individual sachets 17 of a constant predetermined size and in a number appropriate to the shape and dimensions of the respective pockets 13, 14. Each sachet 17 comprises a block 17cur of foamed, synthetic plastics material disposed within a repsective envelope 17b, such envelope being formed by superimposed plies of suitable material, which plies are joined about the periphery of the block as by high freqnency welding. The block comprises an open cell polyurethane foam of rectangular form five inches long, three inches wide and approximately on one and a quarter inches thick, whilst the envelope is formed from air and water impermeable sheet polyvinyl chloride material eight thousandths of an inch thick. Alternatively, the envelope may be formed from reinforced plastics sheet material, for example, that sold under the Trade Mark WAVELOCK", of an equivalent performance. Other foamed plastics materials, whether of open or closed cell form, may be used.The welding together of the superimposed plies of sheet polyvinyl chloride or alternative material will preferably be so effected that the corners are radiussed. The number and distribution of the sachets will vary according to the dimensions and shape of the pocket concerned, a typical arrangement being as shown in Fig.

1 of the drawing.

prises a block of open-cell polyurethane foam.

6. A buoyancy aid as claimed in any one of the preceding claims, wherein each block is of rectangular form.

7. A buoyancy aid as claimed in any one of the preceding claims, wherein the water-impermeable covering to the block comprises sheet polyvinyl chloride material.

8. A sachet for use in conjunction with other like sachets in providing buoyancy in a buoyancy aid, comprising a block of foamed synthetic plastics material, and a water-impermeable covering thereto, and wherein the sachet has a buoyancy of not more than one pound.

9. A sachet as claimed in claim 8, wherein the sachet has a buoyancy of approximatley 0.7 pounds.

10. A sachet as claimed in claim 8 or claim 9, wherein the block is of rectangular form, and the covering fits closely thereabout.

11. A sachet as claimed in any one of claims 8 to 10, wherein the block is a block of open-cell polyurethane foam.

12. A sachet as claimed in any one of the claims 8 to 11, wherein the covering sheet polyvinyl material.

13. A sachet as claimed in any one of claims 8 to 12, secured to a like sachet in adjacent juxtaposition relative thereto, and wherein each sachet is separable from the other without destroying the integrity of either.

14. A buoyancy aid substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

15. A sachet for use in conjunction with other like sachets in providing buoyancy in a buoyancy aid substantially as hereinbefore described with reference to and as illustrated in Fig. 2 of the accompanying drawings.