AU2010100324A4 - Inflatable rescue raft - Google Patents

Description

- 1 AUSTRALIA PATENTS ACT 1990 COMPLETE SPECIFICATION FOR AN INNOVATION PATENT ORIGINAL Name of Applicants: Inflatable Systems Australia Pty Ltd Actual Inventor: Steve Kemp Address for Service is: SHELSTON IP 60 Margaret Street Telephone No: (02) 9777 1111 SYDNEY NSW 2000 Facsimile No. (02) 9241 4666 CCN: 3710000352 Attorney Code: SW Invention Title: INFLATABLE RESCUE RAFT The following statement is a full description of this invention, including the best method of performing it known to us: File: 65630AUP00 - la INFLATABLE RESCUE RAFT FIELD OF THE INVENTION The present invention relates to inflatable life and rescue rafts. The invention has 5 been developed in the preferred embodiment to provide a smaller lightweight open ended rescue raft that can have back pack maneuverability and increased functionality, and will be described herein with reference to this particular application. However, it will be appreciated that the invention is not limited to this particular field of use or intended application and that some or all of the advantages of the invention could be 10 applied to all forms of inflatable rescue rafts. BACKGROUND TO THE INVENTION Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field. 15 Inflatable rescue rafts are known having a range of different configurations. Typically, the rafts will include some form of peripheral inflatable tube element that provides at least part of the flotation capability, and/or operates to define the overall shape of the raft. Such rafts incorporate a floor element that includes the rescue platform on which the rescuers and/or persons to be rescued are supported. In most embodiments, 20 the floor element is also inflatable having a structure similar to that of most conventional inflatable mattresses, having upper and lower layers of material interconnected with bridging elements of the same or a similar material. In most embodiments the bridging is such that a pattern of interconnecting tubes or chambers are formed which together define a floor platform with a ribbed or dimpled structure. In order to achieve a 25 sufficient floor stiffness with these structures, a fairly thick floor element is needed with lots of bridging material which adds considerably to the overall weight of the raft. Other rafts have a non inflatable floor structure and the requisite rigidity is provided by insert panels of marine ply or other suitable rigid materials. Once again such structures can be heavy and cumbersome to transport. 30 Rescue rafts typically fall into two categories. The first type provides a basic life raft function that simply offers a floored enclosure to support one or more persons and keep them out of, or isolated from, underlying elements such as flood waters, rivers, -2 oceans, snow or mud flats etc. With such rafts, the structure is like a boat and entry is over the peripheral inflatable element or tube that defines the periphery of the raft. Often these rafts are designed primarily to support the occupants, rather than facilitate active rescue or enable post rescue conveyance. 5 The second category has a more focused structure designed to better assist rescuers in extracting persons from the underlying elements such as the flood waters. In this category the rafts have some form of close to water level floor platform that is accessible without the need navigate over any peripheral tube element. This has been achieved in one form by providing an open ended raft having a rectangular inflatable 10 floor element of the type described above with a connected peripheral tube structure which extends outwardly and upwardly in loops beyond the floor section, thereby providing access openings to the ends of the floor section. While this type of raft has proved effective in terms of the rescue function, the form of structures used to date has imposed design restrictions on shape and size which 15 has resulted in fairly cumbersome and/or at least relatively heavy rafts, thereby limiting the means by which the raft can be conveyed to the rescue location and their subsequent function. It is an object of the present invention to provide an inflatable rescue raft which overcomes or ameliorates one or more of the disadvantages of the prior art or which at 20 least offers a useful alternative. SUMMARY OF THE INVENTION According to a first aspect of the invention there is provided an inflatable rescue raft, the raft including: 25 an inflatable floor section formed from a coated drop stitch fabric; and an inflatable closed loop tube integrally secured to at least a portion of the peripheral inflatable floor section to provide stabilising support and additional flotation therefore. The term "coated drop stitch fabric" is used herein to refer to coated double cloth 30 fabrics with an interlocking warp resulting in two seperable layers interconnected with numerous individual filaments. Preferably the rescue raft includes a generally rectangular inflatable floor section defining two longitudinal sides interconnected by two opposing ends and the inflatable -3 closed loop tube is secured to the sides of the floor platform and extends beyond the ends to define bow and stern formations that extend outwardly and upwardly from the floor platform ends to define, with said floor ends, bow and stern rescue openings sized to provide direct floor level person access to the floor platform. 5 Preferably the floor thickness is about 50mm. In one preferred form the overall length of the raft is about 3.5m and the overall beam around 1.5m with an internal floor around .09m wide and Xm long.. Ideally, the overall weight is low enough to enable the raft to be readily carried in a back pack without unduly hindering the progress speed of a person carrying the pack. In one preferred form the raft weight is less than 20kgs and 10 more preferably is around 17kgs or less. According to a second aspect of the invention, the raft has an inflatable floor section and an inflatable closed loop tube integrally secured to at least a portion of the periphery of the inflatable floor section to provide stabilising support and additional flotation therefore, and further includes external carry handles, the handles ideally being 15 located at or near the outermost surfaces of the peripheral tubes the raft and is otherwise sized and configured for use as a stretcher on land. In one form a total of four handles are provided disposed ideally near the outer edge surfaces of the fore and aft regions of the respective two portions of the closed loop tube secured to the longitudinal sides of the floor section. Preferably these grab handles are rigid or semi rigid and desirably 20 ergonomically designed to assist lifting of heavy weights, particularly over long distances. Ideally the floor section is constructed from a coated drop stitch fabric as discussed above. According to a third aspect of the invention, the raft has an inflatable floor section and an inflatable closed loop tube integrally secured to at least a portion of the 25 periphery of the inflatable floor section to provide stabilising support and additional flotation therefore, and is otherwise sized and configured to have a total weight of no more than 20kgs and ideally around 17 kilos or less.. Ideally, the raft also includes internally located grab handles for use by the raft occupants and/or one or more peripheral grab lines. External anchor points may also be 30 provided for towing or securing the raft as required. In one preferred form a total of four anchor points are provided, two on each side, each one located adjacent the ends. This arrangement readily facilitates remote manhandling of the raft such as may be useful in a situation where the raft needs to be traversed across a fast narrow waterway.

-4 In preferred forms the raft floor section length to width ratio is approximately 2. Desirably at least the inflatable closed loop tube is constructed from a durable high strength material such as the chlorosulfonated polyethylene (CSPE) synthetic rubber (CSM) material sold under the trade mark Hypalon. 5 In preferred forms the raft may include an optional and desirably removable motor mounting frame, and for versions with open ends, an optional and desirably removable bow shield for search and rescue work. Preferred forms may also be provided with a variety of inflation devices including manual and electric pumps and/or an air tank inflation system for rapid 10 deployment. In yet other aspects of the invention there is provided an inflatable rescue raft that incorporates any one or more of the features described herein which in combination define an innovative step over the prior art. 15 BRIEF DESCRIPTION OF THE DRAWINGS A preferred form of the invention will now be described with reference to the accompanying drawings in which: Figure I is a front perspective view of an open ended rescue raft according to the invention; 20 Figure 2 is a side perspective view of the raft shown in Figure 1 incorporating the optional motor mount and bow wave shield; Figure 3 is a schematic sectional view of the drop stitch fabric used in the floor section of the preferred embodiment; and Figure 4 is a schematic view of an optional air tank inflation system for rapid 25 deployment of the raft. DESCRIPTION OF PREFERRED EMBODIMENTS Referring to Figures 1 and 2 there is illustrated an inflatable rescue raft shown generally at 1. The raft includes an inflatable floor section 2 and an inflatable closed 30 loop buoyancy tube 3. In this preferred embodiment, the raft is configured for active rescue from flood waters and the like. To this end the floor section 2 is generally rectangular with two longitudinal floor sides 4 interconnected by opposing floor ends 5. The buoyancy tube 3 -5 is sized to be larger than the periphery of the floor 2, such that when secured to the longitudinal floor sides 4, two open loops extend outwardly and upwardly beyond the floor ends 5 to define, with the floor ends, bow and stern rescue openings 6 and 7 respectively. With appropriate sizing this arrangement enables rescue personnel seated 5 on the floor of the raft to pull in victims from the water, for example, through the openings without having to haul them over the buoyancy tubes. In the preferred forms the floor is constructed from a coated drop stitch fabric, which is a double layered fabric with an interlocking warp stitch structure which has two separable layers interconnected with numerous lightweight filaments as shown in Figure 10 3. This results in a very lightweight yet rigid structure once inflated. The thickness of the floor in the preferred form is around 50mm which is significantly thinner and certainly lighter in weight than material web mattress type structures used in the prior art as discussed above. In one form the overall length of the raft is around 3.5m and the overall beam around 1.5m with an internal floor having 15 dimensions around 0.9m wide by about 1.95 to 2.Om long. The tube diameter is around 0.3m. It will be appreciated that the lowermost portions of the tube that are secured to the floor section extend beyond the floor length and that the ratio above relates solely to the floor section. Ideally, the overall weight is low enough to be readily carried in a back pack 20 when needed for use in hard to access areas. To this end the raft ideally has a total weight of less than 20kgs and more ideally is around 17kgs or less. In the preferred form shown the raft I also includes external carry handles 7, ideally located at or near the outermost surfaces of the side portions of the buoyancy tube 3. As shown, the raft preferably has four handles, two on each side located toward 25 the fore and aft regions. Preferably the handles are rigid or simi rigid moulded handles designed to assist in carrying the raft, with or without a victim on board, over reasonable distances if required. Similar internal handles 8 also may be provided for use by the occupants of the raft. The raft also includes one or more peripheral grab lines 9 and ideally also 30 includes a number of external anchor points 10 for towing or securing the raft as required. In one preferred form as shown, a minimum of four anchor points are provided, two on each side, each one located toward an adjacent end. This arrangement -6 facilitates remote manhandling of the raft via a system of multiple ropes such as may be useful in a situation where the raft needs to be traversed across a fast narrow waterway. The raft is preferably constructed to have a number of separate chambers. In the preferred form the floor comprises one chamber and the buoyancy tube as two separate 5 chambers. Inflation and pressure relief valves are provided as required. Preferably at least the inflatable closed loop tube is constructed from a durable high strength material such as the chlorosulfonated polyethylene (CSPE) synthetic rubber (CSM) material sold under the trade mark Hypalon. Referring next in particular to Figure 2 there is shown the raft with an optional 10 motor mounting frame 11 attached. The frame 11 has a generally v shaped element 12 which connects to the stern end 13 of the raft via, for example, means such as a hook and loop strapping arrangement, and a cross member 14 which connect to the sides of the buoyancy tube to extend just behind the stern floor end 5. In the form illustrated the cross member has at its ends two arm portions 15 which slide into corresponding pocket 15 formations 16 provided on the tube, prior to the apex portion of the v shaped element then being secured to the stern portion of the tube as described. A motor 16 can then be secured to the cross member 14 as shown. Also provided as an optional extra component for use when a motor is attached is a removable bow wave shield 17. The bow shield 17 can take any suitable form such as 20 a semi rigid flap section that secures to the floor and the buoyancy tube or may comprise a sock type cover that extends over the front portion of the raft. Referring next to Figure 4 there is shown a schematic view of an optional air tank inflation system that can be used for rapid deployment of the raft. The system includes a compressed air tank 18 with a safety catch or pin arrangement 19, a feed tube 25 20 and an operating handle 21 which needs to be depressed to operate the outlet valve ( not shown). In use the tube is connected to the inlet valve on the raft, the safety catch disarmed and then inflation is controlled by the operator by depressing the handle 21 which opens the valve and lets the air into the feed tube 20 and into the raft. In the past most rafts that have used compressed air inflation systems have the tanks built into the 30 rafts, and once the safety catches are released inflation is automatic and uncontrolled. One advantage of the current system is that the tank can be carried separately to the raft. Another is the added advantage of operator control which can be important in rugged or dangerous terrain where continuous rapid inflation could be hazardous. Naturally the -7 raft of the invention could also be inflated by any other suitable means using, for example, manual or electric pumps. The raft of the invention, particularly in the preferred form, has numerous advantages over the prior art. Firstly, the size and structure means that at around 17kgs 5 it is, to the applicants knowledge, the lightest rescue raft available that is rated for a crew of 2 and successfully tested with three on white water. The low weight makes it easy for the raft to be carried in a backpack when needed in hard to access areas. Every kilo makes a significant difference when conveying through difficult terrain like canyons etc. Prototype testing has also shown the craft to be incredibly stable due to the rigid 10 floor structure enabled in a light weight form by use of the drop stitch fabric. Furthermore, with the floor being low in height as well as flat and fairly rigid, the task of hauling incapacitated victims from the water is made a lot easier than with other rafts. Another advantage of the raft arises from the incorporation of external carry handles conveniently located at the peripheral sides of the buoyancy tubes fore and aft. 15 Combined with the rigid floor structure, the raft readily doubles as a very effective and easy to use stretcher when needing to carry a victim by foot from the water hazard area to a road based rescue facility. While prior art rafts have included grab lines such as those provide on the raft of the invention, these do not operate particularly effectively or comfortably as carrying handles for this purpose. 20 Yet a further advantage arises from the overall shape of the raft which has a preferred floor length to width ratio of around 2. Prior art rescue rafts have tended to be longer and narrower, possibly due to limitations imposed by the inferior floor structures. Such longer structures suffer from too much flex which limits their function and makes them less stable and less effective particularly in turbulent water conditions. 25 It will be appreciated that while the invention has been described in one particularly preferred raft structure, it can be embodied in many other ways without departing from the scope of the invention.

Claims (19)

1. An inflatable rescue raft, the raft including: an inflatable floor section formed from a coated drop stitch fabric; and 5 an inflatable closed loop tube integrally secured to at least a portion of the peripheral inflatable floor section to provide stabilising support and additional flotation therefore.

2. A rescue raft according to claim I wherein the floor section includes a generally 10 rectangular inflatable floor section defining two longitudinal sides interconnected by two opposing ends and the inflatable closed loop tube is secured to the sides of the floor platform and extends beyond the ends to define bow and stern formations that extend outwardly and upwardly from the floor platform ends to define, with said floor ends, bow and stern rescue openings sized to provide direct floor level person access to the 15 floor platform.

3. An inflatable rescue raft according to claim I or claim 2 wherein the floor thickness is about 50mm. 20

4. An inflatable rescue raft according to any one of the preceding claims where the raft weight is less than 20kgs.

5. An inflatable rescue raft according to claim 4 wherein the raft weight is around 17kgs or less. 25

6. An inflatable rescue raft wherein the raft has an inflatable floor section and an inflatable closed loop tube integrally secured to at least a portion of the periphery of the inflatable floor section to provide stabilising support and additional flotation therefore, and further includes external carry handles located and configured for use of the raft as a 30 stretcher on land.

7. An inflatable rescue raft according to claim 6 wherein a total of four handles are provided disposed near the outer edge surfaces of the fore and aft regions of the -9 respective two portions of the closed loop tube secured to the longitudinal sides of the floor section.

8. An inflatable rescue raft according to claim 7 wherein the grab handles are rigid or 5 semirigid.

9. An inflatable rescue raft according to any one of claims 6 to 8 wherein the floor section is constructed from a coated drop stitch fabric. provided a raft that incorporates any one or more of the features described herein which in combination define an 10 innovative step over the prior art.

10. An inflatable rescue raft including an inflatable floor section and an inflatable closed loop tube integrally secured to at least a portion of the periphery of the inflatable floor section to provide stabilising support and additional flotation therefore, wherein the 15 raft is otherwise sized and configured to have a total weight of no more than 20kgs.

11. An inflatable rescue raft according to claim 10 wherein the total weight is around I 7kgs or less. 20

12. An inflatable rescue raft according to any one of the preceding claims including one or more internally located grab handles for use by the raft occupants.

13. An inflatable rescue raft according to any one of the preceding claims where in the raft also includes one or more peripheral grab lines. 25

14. An inflatable rescue raft according to any one of the preceding claims including external anchor points for towing or securing the raft as required.

15. An inflatable rescue raft according to any one of the preceding claims wherein the 30 the raft floor section length to width ratio is approximately 2.

16. An inflatable rescue raft according to any one of the preceding claims wherein at least the inflatable closed loop tube is constructed from a durable high strength material - 10 such as the chlorosulfonated polyethylene (CSPE) synthetic rubber (CSM) material sold under the trade mark Hypalon.

17. An inflatable rescue raft according to any one of the preceding claims wherein raft 5 includes an optional and desirably removable motor mounting frame.

18. An air tank inflation system for rapid deployment of inflatable craft and the like, the system including: a tank of compressed air; 10 an outlet valve; a feed tube in fluid flow communication with the outlet valve; an actuator for opening the outlet valve; and a safety mechanism for preventing and permitting operation of the actuator. . 15

19. An inflatable rescue raft that incorporates any one or more of the features described herein which in combination define an innovative step over the prior art.