WO2014037692A1

WO2014037692A1 - Improved lifejacket inflation system

Info

Publication number: WO2014037692A1
Application number: PCT/GB2013/000368
Authority: WO
Inventors: Brian Spence MACKENZIE
Original assignee: Mackenzie Brian Spence
Priority date: 2012-09-06
Filing date: 2013-09-03
Publication date: 2014-03-13
Also published as: GB2507032B; GB2507032A; GB201215938D0

Abstract

A lifejacket inflation system is described. The lifejacket inflation system comprises an inflation valve adapted to be attached to a lifejacket, the inflation valve defining an inlet adapted to engage the neck of a refillable gas cylinder. The inflation valve includes a pin, the pin being movable from a normal position to an extended position, in the extended position the pin being adapted, in use, to penetrate the refillable gas cylinder, the inflation valve defining an engagement surface, the engagement surface adapted to engage a refillable gas cylinder surface such that in the normal position the pin is spaced away from the refillable gas cylinder

Description

Improved Lifejacket Inflation System

Field of the Invention

This invention relates to improvements in life preservers, and in particular to the inflators of self-inflating lifejackets provided with a pressurised reservoir of gas which may be utilised to inflate the lifejacket when required.

Background to the Invention

Lifejackets provided in aircraft are generally stored in a deflated condition and, if required for use in an emergency, may be inflated by accessing a pressurised gas reservoir attached to a lifejacket inflation valve by piercing the cap on a small C0₂ gas cylinder. The cap is pierced by the application of a force to an inflation valve lever which in turn presses on a firing pin, creating a movement of the pin towards, and through, the gas cylinder cap. The lifejackets are single use items and are discarded after use. However, in many jurisdictions persons who work offshore are required to attend survival training courses during which they will practice using such lifejackets. In such circumstances lifejackets are used many times; after use

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lifejackets are deflated and the gas cylinders replaced. As the conventional gas cylinder is a single use item, the replacement is relatively expensive and may represent a significant outlay to the organisers of these safety training courses.

Adapters have been proposed to permit the use of refillable gas cylinders with self inflating lifejackets. An example is provided in GB 2268712 by the same applicant. However, adapters such as these have drawbacks. It has been found that over time the seal between the gas cylinder and the valve can become over compressed reducing the distance over which the firing pin can travel reducing the ability of the user to generate sufficient pin momentum for the pin to pierce the gas cylinder cap. As such, to maintain optimum performance, regular removal and replacement of the seals is required. This can be a time-consuming business.

Furthermore, if the seal replacement is part of a maintenance routine, the seal may be removed unnecessarily as it is found to be in perfect working condition when it is removed from the inflation valve.

Summary of the Invention

According to a first aspect of the present invention there is provided a lifejacket inflation system comprising: an inflation valve adapted to be attached to a lifejacket, the inflation valve defining an inlet adapted to engage the neck of a refillable gas cylinder, the inflation valve including a pin, the pin being movable from a normal position to an extended position, in the extended position the pin being adapted, in use, to penetrate the refillable gas cylinder, the inflation valve defining an engagement surface, the engagement surface adapted to engage a refillable gas cylinder surface such that in the normal position the pin is spaced away from the refillable gas cylinder.

By spacing the pin away from the refillable gas cylinder in the normal position, in at least one embodiment of the present invention, it is possible to provide a distance over between the tip of the pin in the normal position and the gas cylinder cap of suitable length for the user to generate sufficient momentum in the pin to pierce the gas cylinder cap more easily.

The inflation valve engagement surface may, in use, form a metal to metal contact with the refillable gas cylinder engagement surface.

The inflation valve may comprise a valve body and an adapter. The adapter may define a female inlet and a male outlet, the female inlet adapted to receive the neck of a refillable gas cylinder and the male outlet adapted to be received by the inflation valve body.

The inflation valve may further comprise a first seal for providing a seal, in use, between the neck of a refillable gas cylinder and the adapter inlet, and a second seal for providing a seal, in use, between the adapter outlet and the inflation valve.

In one embodiment, in use, the first seal is seated on the neck of the refillable gas cylinder and the second seal is seated on the adapter male outlet.

The first seal may be an O-ring.

The second seal may be an O-ring.

In one embodiment, the inflation system defines a flow path providing, in use,

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fluid communication between a refillable gas cylinder and a lifejacket. In this embodiment, the flow path comprises an inflation valve flow path and an adapter flow path.

Where there is an adapter flow path, the adapter flow path extends from an adapter inlet to the adapter outlet.

Where there is an inflation valve flow path, the flow path extends from an inflation valve inlet, adapted to receive the adapter outlet, to an inflation valve outlet, the flow path providing, in use, fluid communication between the adapter outlet and the lifejacket. In use, the inflation valve outlet is connected to the lifejacket and is in fluid communication with the lifejacket interior.

The pin may define an at least partially smooth surface. Alternatively or additionally the pin may define an at least partially spiral surface.

The pin may have a piercing end adapted to pierce, in use, the gas cylinder seal. The pin may have a head end, opposite the piercing end.

The inflation valve may further include a trigger mechanism comprising a trigger and a trigger actuation device. The trigger mechanism is provided to allow users to activate the inflation system, and is generally in the form of a toggle attached to a trigger, a sharp pull on the toggle activating the trigger system through the trigger.

The pin may be biased to the normal position. In the normal position, the pin head end is adjacent the trigger.

The pin may be biased to the normal position by means of a spring.

Activation of the trigger mechanism may move the pin, against the bias, to the extended position.

The pin may be located in the inflation valve flow path.

In the normal position, a pin portion may be located adjacent the inflation valve flow path outlet.

The pin portion may be configured to improve, in use, the flow of compressed air from the gas cylinder into the lifejacket.

The pin portion may define a reduced cross-sectional area.

The pin may extend into the adapter flow path.

The adapter may further include a pin guide.

The pin guide may extend into and/or define the adapter flow path.

The pin guide may be separate from the adapter. In an embodiment, the pin guide may be fixed to an internal surface of the adapter outlet.

The pin guide may be adapted to direct the pin, in use, towards the refillable gas cylinder seal as the pin moves from the normal position to the extended position. If the pin deviates from a substantially linear path, it may impact on the non-seal surface of the gasi cylinder potentially blunting the pin. Providing a guide improves the consistency of impact of the pin on the seal.

The guide may form an interference fit with the adapter body, particularly the adapter outlet.

The guide may be formed from a resilient material. The guide may be formed from spring steel for example. Where the guide is formed from spring steel, it may be rolled into a substantially tubular shape.

According to a second aspect of the present invention there is provided a lifejacket inflation system comprising:

an inflation valve adapted to be attached to a lifejacket, the inflation valve comprising a valve body and an adapter, the adapter defining a female inlet and a male outlet, the female inlet adapted to receive the neck of a refillable gas cylinder and the male outlet adapted to be received by the inflation valve body; and

a first seal for providing a seal, in use, between the neck of a refillable gas cylinder and the adapter inlet, and a second seal for providing a seal, in use, between the adapter outlet and the inflation valve;

wherein, in use, the first seal is seated on the neck of the refillable gas cylinder and the second seal is seated on the adapter male outlet.

Seating the first and second seals on the male surfaces of the connecting components permits inspection in situ by simply dismantling the lifejacket inflation system. As the system is dismantled, the seals remain in their seats on the male external surfaces. In this way, the seals are only removed from their seats and are only changed when they are showing signs of deterioration.

The inflation valve may comprise a pin. A pin is provided to pierce the seal of the refillable gas cylinder. According to a third aspect of the present invention there is provided a lifejacket inflation valve comprising:

a body adapted to be attached to a lifejacket, the body defining an inlet and an outlet; and

a pin, the pin being movable with respect to the body from a normal position to an extended position, the pin defining a pin portion which in the normal position is positioned adjacent the body outlet, the pin portion having a cross-sectional area, the pin portion cross-sectional area been less than the cross-sectional area than the average pin cross-sectional area.

Providing a pin portion of reduced cross-sectional area allows the flow of air from the inlet to the outlet to be subject to a minimal disruption and flow as is the case with conventional jackets.

The preferred and alternative features listed with respect to the first aspect of the invention may also be applicable to be second and third aspects but have not been repeated for brevity.

Brief Description of the Drawings

An embodiment of the present invention will now be described with reference to the accompanying Figures in which:

Figure 1 is a side view of a lifejacket inflation system according to an embodiment of the present invention;

Figure 2 is an exploded view of the lifejacket inflation system of Figure 1

Figure 3 is a section of the lifejacket inflation system of Figure 1 prior to firing;

Figure 4 is a section of the lifejacket inflation system of Figure 1 during firing; and Figure 5 is a section of the lifejacket inflation system of Figure 1 after firing.

Detailed Description of the Drawings

Reference is made to Figures 1 and 2, side and exploded views respectively of a lifejacket inflation system, generally indicated by reference numeral 5, according to a first embodiment of the present invention.

The lifejacket inflation system 5 comprises an inflation valve 10 adapted to be connected to a lifejacket (a portion of which is shown in broken outline) 12, and an adapter 14 having a body 28 defining a female inlet 16 and a male outlet 18, the female inlet 16 adapted to receive the neck 20 of a refillable gas cylinder 22 and the male outlet 18 adapted to be received by the inflation valve 12. The female inlet defines an engagement surface 17 adapted to engage a cylinder surface 19, the purpose of the engagement being described in due course.

The lifejacket inflation system 5, further includes a first seal 24 for providing a seal between the; gas cylinder neck 20 and the adapter inlet 16, and a second seal 26 for providing a seal between the adapter outlet 18 and inflation valve 10.

The gas cylinder neck 20 defines a recess 30 adapted to seat the first seal 24 such that when the cylinder 20 is removed from the adapter inlet 16, the first seal 24 remains associated with the gas cylinder 22 and can be visually inspected upon removal of the cylinder 22 from the adapter 14. This results in less time being spent on maintenance and more confidence on the part of the users that the lifejacket inflation system 5 will work correctly. It is counterintuitive to install the first seal 24 on the cylinder 22 as a conventional cylinder is an off-the-shelf item and doesn't include provision to accommodate an external seal. Whilst there is more work created by adapting the cylinder neck 20 to receive the first seal 24, the improvements and cost savings realised from having the first seal 24 on an exposed male surface as opposed to an unexposed female surface make the adaptions a worthwhile investment.

Similarly, the male adapter outlet 18 includes a recess 32 adapted to receive the second seal 26. Again this is to allow inspection of the first seal when the adapter is removed from a lifejacket inflation valve inlet 34, realising the same advantages as previously described.

The inflation valve 10 defines an inflation valve flow path 36 between the inflation valve inlet 34 and an inflation valve outlet 38 which is in fluid communication with the interior of the lifejacket 12, such that compressed gas flowing through the inflation valve flow path 36 can feed into the lifejacket 12 and inflate the lifejacket 12. The inflation valve 10 further includes a firing trigger 38, a pin 40 and a retention spring 42. The purposes of the trigger, pin and spring 38, 40, 42 will be described in due course. As will also be described, the adapter 14 includes a guide 46 to guide the pin 40 towards a gas cylinder seal 48 which seals an opening 50 defined by the gas cylinder 22. As the gas cylinder 22 reusable, after use the gas cylinder seal 48 can be replaced by removal of a bush 52 which traps the gas cylinder seal 22 in the cylinder neck 20.

The operation of the lifejacket inflation system 5 will now be described with reference to Figures 3, 4 and 5, sections of the lifejacket inflation system 5 of Figure 1 in pre-firing, during firing and post-firing configurations respectively.

In the pre-firing configuration shown in Figure 3, the pin 40 is located in the inflation valve flow path 36 defined by the valve 10 and extends into the adapter guide 46. The adapter guide 46 is a "c"-shaped, piece of spring steel which forms an interference fit with the adapter body 28 at the adapter outlet 18. The pin 40 and extends through the adapter guide 46 towards the gas cylinder seal 48 which is secured in the cylinder neck 20 by the cylinder bush 52. The cylinder bush 52 is threadedly attached to an internal surface of the cylinder neck 20 and is removed from the cylinder neck 20 by means of an allan key.

The pin 40 is biased to the position shown in Figure 3 by the spring 42. In this normal position, the force of the spring 42 against a lip 56 defined by the adapter body 58, pushes the pin 40 towards the firing trigger 44.

The firing trigger 44 is activated by means of a toggle 60 attached to the firing trigger 44 by a string 62. As the user pulls the toggle 60 downwards, the firing trigger 44 rotates about a pivot 64 and a firing trigger head 66 pushes against a pin head 68, moving the pin 40 in a substantially linear direction towards the gas cylinder seal 48 to an extended position. As can be seen from Figure 4, the spring 42 is compressed during this action however the force on the toggle 60 is sufficient to resist the bias of the spring 42 and the pin 40 pierces the gas cylinder seal 48.

Continued application of a pull force to the toggle 60 pivots the firing trigger 44 passed the pin head 68, and the pin 40 returns to the normal position under the action of the spring 42.

The metal to metal contact between the female inlet engagement surface 17 and the cylinder surface 19 provides a consistent spacing between the tip of the pin 41 and the gas cylinder seal 48. This is an advantage over the prior art in which the interface between the inflation valve and the cylinder is provided by a seal which, over time, compresses. If the seal compresses sufficiently, the pin is, in the normal position, very close to the gas cylinder seal and, as a result, it is difficult to get sufficient momentum into the pin by activation of the firing trigger to pierce the gas seal. The retraction of the pin 40 is also assisted by the rush of compressed air from the gas cylinder 22 through the cylinder neck 20 and adapter 14, and into the lifejacket (not shown) through the flow path outlet 38.

As can be seen from Figures 3 and 5, the pin 40 including narrowed portion 70 adjacent the flow path outlet 38 when the pin 40 is in the retracted position. This is to minimise the obstruction to the flow of air as it changes direction and flows into the lifejacket (not shown).

Claims

1 A lifejacket inflation system comprising:

an inflation valve adapted to be attached to a lifejacket, the inflation valve defining an inlet adapted to engage the neck of a refillable gas cylinder, the inflation valve including a pin, the pin being movable from a normal position to an extended position, in the extended position the pin being adapted, in use, to penetrate the refillable gas cylinder, the inflation valve defining an engagement surface, the engagement surface adapted to engage a refillable gas cylinder surface such that in the normal position the pin is spaced away from the refillable gas cylinder.

2. The system of claim 1 , wherein the inflation valve engagement surface, in use, forms a metal to metal contact with the refillable gas cylinder engagement surface.

3. The system of claim 1 or claim 2, wherein the inflation valve comprises a valve body and an adapter.

4. The system of claim 3, wherein the adapter defines a female inlet and a male outlet, the female inlet adapted to receive the neck of a refillable gas cylinder and the male outlet adapted to be received by the inflation valve body.

5. The system of claim 4, wherein the inflation valve further comprises a first seal for providing a seal, in use, between the neck of a refillable gas cylinder and the adapter inlet and the second seal for providing a seal, in use, between the adapter outlet and the inflation valve.

6. The system of claim 5, wherein the first seal is seated on the neck of the refillable gas cylinder and the second seal is seated on the adapter male outlet.

7. The system of claim 5 or 6, wherein the first seal is an O-ring seal.

8. The system of claim 5, claim 6 or claim 7, wherein the second seal is an O- ring seal.

9. The system of any of claims 3 to 8, wherein the inflation system defines a flow path providing, in use, fluid communication between a refillable gas cylinder and a lifejacket.

10. The system of claim 9, wherein the flow path comprises an inflation valve flow path and an adapter flow path.

11. The system of claim 10, wherein the adapter flow path extends from an adapter inlet to the adapter outlet.

12. The system of claim 11 , wherein where it is an inflation valve flow path, the flow path extends from an inflation valve inlet, adapted to receive the adapter outlet, to an inflation valve outlet, the flow path providing, in use, fluid communication between the adapter outlet and the lifejacket.

13. The system of any preceding claim, wherein the pin defines an at least partially spiral surface.

14. The system of any preceding claim wherein the pin has a piercing end adapted to pierce, in use, the gas cylinder seal and a head end, opposite the piercing end.

15. The system of claim 14, wherein the inflation valve further comprises a trigger mechanism comprising a trigger and a trigger actuation device.

16. The system of claim 15, wherein the pin is biased to the normal position, in the normal position the pin head end being adjacent the trigger.

17. The system of claim 16, wherein the pin is biased to the normal position by means of a spring.

18. The system of claim 17, wherein activation of the trigger mechanism moves the pin, against the bias, to the extended position.

19. The system of any of claims 10 to 18, when dependent on claim 10, wherein the pin is located in the inflation valve flow path.

20. The system of claim 19, wherein in the normal position, a pin portion is located adjacent the inflation valve flow path outlet.

21. The system of claim 20, wherein the pin portion is configured to improve, in use, the flow of compressed air from the gas cylinder into the lifejacket.

22. The system of claim 21 , wherein the pin portion defines a reduced cross- sectional area.

23. The system of any of claims 10 to 22, dependent on claim 10, wherein the pin extends into the adapter flow path.

24. The system of claim 23, wherein the adapter further includes a pin guide, the pin guide extending into and/or defining the adapter flow path.

25. The system of claim 24, wherein the pin guide is separate from the adapter.

26. The system of either of claims 24 or 25, wherein the pin guide is adapted to direct the pin, in use, towards the refillable gas cylinder seal as the pin moves from the normal position to the extended position.

27. The system of any of claims 24 to 26, wherein the pin guide forms an interference fit with the adapter body, particularly the adapter outlet.

28. The system of any of claims 24 to 27, wherein the guide is formed from a resilient material.

29. A lifejacket inflation system comprising:

30. The system of claim 29, wherein the inflation valve includes a pin, the pin being movable from a normal position to an extended position, in the extended position the pin being adapted, in use, to penetrate the refillable gas cylinder, the inflation valve defining an engagement surface, the engagement surface adapted to engage a refillable gas cylinder surface such that in the normal position the pin is spaced away from the refillable gas cylinder.

31. A lifejacket inflation valve comprising: