GB2256832A - Covers for inflatable bladders - Google Patents

Abstract

A lifejacket (10) comprises an inflator (20) protected in the uninflated condition by a cover (18), which is maintained in position by female press studs (35a, 35d) mounted on release straps (36) and passing through apertures (34) in edge portions of the cover (18) to engage male studs (32a, 32d) mounted on overlying cover portions. On inflation, the direct effect of the expanding inflator (20) tending to burst the press studs (32, 35) apart is supplemented by a pull on each strap (36) exerted by the expanding inflator neck portion (22) around which an end of each strap (36) passes. <IMAGE>

Description

IMPROVEMENTS RELATING TO COVERS FOR INFLATABLE BLADDERS This invention relates to means for disengaging one or more fasteners securing a cover or other enclosure around an inflatable bladder.

In many applications, for example, in inflatable lifejackets, an inflatable bladder is contained in its uninflated condition within a cover and is arranged on inflation to burst out of the cover, disengaging the fasteners which secured the cover around the bladder. For example, in the case of an inflatable lifejacket an inflator is contained within an outer cover which is secured in position around the inflator by press studs mounted along overlapping marginal edge portions of the cover. It is very difficult to arrange the position and inter-engagement of the press studs so that they will retain the lifejacket in its compact condition for normal wear without accidental disengagement of the studs, and yet ensure that all the studs will consistently disengage on inflation.

It is an aim of the present invention to provide means which will ensure consistent disengagement of fastening means securing a cover in place around an uninflated inflatable bladder on inflation of the bladder.

According to the present invention there are provided release means for releasing fastening means for securing a cover around an uninflated bladder, the release means comprising means for exerting on the fastening means a disengaging force generated by inflation of the bladder and which is in a direction different from the disengaging force directly exerted on the fastening means by the inflating bladder.

Preferably the fastening means take the form of a series of female press studs mounted along one marginal edge portion of the cover and a corresponding series of male studs mounted along an overlapping portion of the cover. The means for exerting a further disengaging force on the pairs of engaged studs may take the form of a strap secured to the cover along the row of female studs and having an upper extension arranged around a neck portion of the lifejacket inflator such that, on inflation, the female studs are pulled upwards relatively to the male studs to provide a disengaging force which supplements the force acting in the circumferential direction to burst the studs apart.More preferably one set of fasteners is mounted on the strap itself, each projecting through an aperture formed in the underlying edge portion to engage a cooperating fastener mounted on the overlying edge portion.

The release means of the present invention may be applied to forms of fastening means other than press studs, for example "touch and close fasteners sold under the name "Velcro"; rip cords; and tear strips. It will be appreciated that the strap or other member for exerting a disengaging force need not necessarily be mounted inside the cover although this protected position is generally preferable from the practical point of view, for example to reduce the risk of accidental snagging.

It is often advantageous that the additional disengaging force should not be exerted simultaneously on all of a series of fastenings, and successive application of the disengaging force may be arranged by leaving a slack length of strap or other flexible member between one or more adjacent pairs of attachment points.

Although the preferred forms of the invention have been described with particular reference to lifejackets, it is stressed that the invention is applicable to all applications in which an inflatable bladder is contained within a cover.

Although the invention may be carried out in many different ways one particular embodiment thereof will now be described, by way of example, with reference to the accompanying drawings in which Figure 1 is a front elevation of an inflatable lifejacket according to the invention; Figure 2 is a rear view, partly cut away, of the jacket of Fig. 1; Figure 3 is a section on the line A-A of Fig. 2; and Figure 4 is a front elevation of the jacket in the inflated condition.

As shown in Figs. 1 and 2 an inflatable lifejacket 10 has the general shape of an inverted V and comprises a neck portion 12 and two arm portions 14,16 of constant width which overlie the respective sides of a wearer's chest, the jacket being attached to the wearer by means of a conventional arrangement of straps (not shown).

The jacket 10 comprises a cover 18 which normally contains an uninflated inflator 20 which is arranged to be inflated when required by manual and/or automatic inflation means (not shown) which include a cylinder of compressed gas. The inflator 20 comprises a neck portion 22 and two lobes 24,26. As will be seen from Fig. 4 the lobes 24,26 are considerably wider than the arm portions 14,16 and are normally folded as shown in Fig. 3 so as to be accommodated within the respective sleeve portions 28,29 of the cover 18, the sleeve portions 28,20 being bridged at their upper ends by a neck portion 31 closed by press studs 30.

In a conventional lifejacket of the above-described type the edges of each cover arm portion are held together around the folded lobe by means of a series of press studs.

In the lifejacket 10 a series of four male press studs 32a-32b (see Figs. 2 and 3) is mounted down the overlying edge portion of each sleeve portion 28,29 of the cover 18 while a series of corresponding apertures 34 is provided down the other, underlying edge portion (not visible in Fig. 2). The two edge portions are held together by the engagement of the male studs 32a-32d with corresponding ones of a series of female studs 35a-35d mounted on a release strap 36. Each strap 36 is secured only at its upper end to an attachment point at the inside front of the neck portion 31 of the cover 18. Each strap is arranged to pass upwards over the front of the inflator neck portion 22 and then downwards over the rear thereof where it passes freely through a retaining strap 38.It will be noted that the top female stud 35a and the next lower stud 35b are mounted on the strap 36 at a greater distance apart than the coresponding male studs 32a,32b so as to leave a slack portion 40 of the strap 36.

On inflation of the inflator the expansion of the lobes 24,26 exerts a force which acts generally outwards and tends to separate each pair of male and female studs 32a-d,35a-d in the normal way. However, the inflation of the inflator neck portion 22 exerts an upward force on the studded length of each strap 36. Because of the slack portion 40 this upward force is initially concentrated on each top female stud 35a, thus providing an additional separating force on the studs where less expansive force is exerted by the inflator lobes 24,26 which are narrower at this point. After the top pairs of studs 32a,35a have separated, the slack at portion 40 is taken up and an upward pull is exerted on the remaining three female studs 35b,35c, 35d ensuring that each inflator lobe 24,26 bursts out fully and the jacket assumes the fully inflated condition shown in Fig. 4.

It will be appreciated that the arrangement of the present invention supplements the conventional separating force acting in the circumferential direction of the sleeves 28,29 by a force acting in the longiudinal direction of the sleeves 28,29, thus providing for great consistency in achieving timely and complete separation of the cover fastenings on inflation.

Claims (11)

CLAIMS:

1. Release means for releasing fastening means for securing a cover around an uninflated bladder, the release means comprising disengaging means for exerting on the fastening means a disengaging force generated by inflation of the bladder and which is in a direction different from the disengaging force directly exerted on the fastening means by the inflating bladder.

2. Release means as claimed in claim l, in which the disengaging means comprise a flexible member arranged to transmit a disengaging force generated by inflation of a part of the bladder remote from the fastening means.

3. Release means as claimed in claim 2, in which the fastening means comprise one or more fastener elements mounted along one marginal edge portion of the cover, and one or more co-operating fastener elements mounted along an overlying portion of the cover, the flexible member being secured to the cover along - said marginal edge portion thereof.

4. Release means as claimed in claim 2, in which the fastening means comprise one or more fastener elements mounted on the flexible member, the or each element projecting through an aperture formed in an underlying marginal edge portion of the cover, and one or more co-operating fastener elements mounted on an overlying edge portion of the cover and engageable with said fastener elements.

5. Release means as claimed in claim 3 or 4, in which said fastener elements are female press studs and said co-operating elements are male press studs.

6. Release means as claimed in any one of claims 2 to 5, in which said flexible member is arranged with a slack length between one or more adjacent pairs of points of attachment to the cover or fastening means.

7. A life jacket incorporating release means as claimed in any preceding claim.

8. A life jacket incorporating release means as claimed in any one of claims 2 to 6, in which the flexible member is arranged to transmit a disengaging force generated by inflation of a neck portion of the life jacket inflator.

9. Release means as claimed in claim l and substantially as herein described.

10. Release means substantially as hereinbefore described with reference to the accompanying drawings.

11. The features hereinbefore described, or their equivalents, in any novel, patentable selection.