AU2008201499B2

AU2008201499B2 - Device for uni-directional flow of liquid into a reservoir

Info

Publication number: AU2008201499B2
Application number: AU2008201499A
Authority: AU
Inventors: Christopher Herbert Black; Holly Meredith Turner
Original assignee: Aerial Fire Control Int Pty Ltd
Current assignee: Aerial Fire Control International Pty Ltd
Priority date: 2007-04-04
Filing date: 2008-04-02
Publication date: 2012-11-29
Anticipated expiration: 2028-04-02
Also published as: AU2008201499A1

Abstract

A device (1) is disclosed fitted to a reservoir (13) of the type used as an aerial borne dump bucket for water bombing bush fires. The device (1) includes complementary inner (2a) and outer (2b) peripheral frame members 5 surrounding an open port (3) which extends through the side wall (4) of the reservoir (13). A plate (7) is pivotally attached to the inner surface of the inner frame member (2a). A flexible membrane (11) is fitted to that surface of the plate (7) which faces the port (3). The dimensions of the plate (7) and membrane (11) are such that, when the device is in the closed position, the 10 membrane (11) is a liquid seal to the port (3). The upper edge (12) of the plate (7) is angled inwards sufficient to abut the inner frame member (2a) at an inclination when the device is in its maximum open position to prevent further inward movement of the plate (7). As the reservoir is lowered into a body of water, a pressure differential opens the seal allowing ingress of water. 15 As the filled reservoir is raised from the body of water, a pressure differential closes the seal preventing egress of the contained water. *r .t..gge 1" A'WSTE!' -~C4 -c nct. '. 299 5Z 7 g;,. .192 COTR C Y- a 9 l 2 ' l d "-1 g0 ro FlF tS 7-7 COM I N: BMI.000025 le ia 419 usran. ma(Ho 2 0 O ('-

Description

TITLE: DEVICE FOR UNI-DIRECTIONAL FLOW OF LIQUID INTO A RESERVOIR THIS INVENTION relates to liquid carrying vessels. In particular, it is directed to a device to assist the entry of a liquid into, and retaining within, a reservoir. 5 The present invention finds especial, but not limiting, use in a dump bucket typically used in the release of water from an aerial-borne bucket, often a helicopter, over a forest, bush or similar fire in remote and/or inaccessible regions. Throughout this specification, unless the contrary is expressly stated, where 10 a document, act or item of knowledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was, at the priority date, publicly available, known to the public, part of the common general knowledge, or known to be relevant to an attempt to solve any problem with which this 15 specification is concerned. Most prior technology fire-fighting water-carrying vessels to be suspended beneath a helicopter comprise a reservoir to hold the water, at least one valve within the reservoir, usually at its base, through which the water can be dispensed, and a variety of mechanisms for the release of the water. The 20 vessels of this prior technology suffer one or more of the following disadvantages: (1) if the reservoir is manufactured from a rigid material, storage and transport of the "empty" vessel can be difficult, inconvenient and relatively costly; (2) there is insufficient flow around the dump valve to allow filling to take place through the open valve; (3) even if filling through a dump 5r valve is possible, the volume of the reservoir is sufficiently large that such filling is time consuming; (4) where the reservoir is made of a flexible material, its buoyancy is such that water will not flow through the open valve, thus limiting the reservoir to be filled from the open top of the reservoir only; (5) where the reservoir is made of a flexible material, its buoyancy is such that the reservoir will not submerge into the water, even when the dump valve is open and, in order to overcome this problem, weights - usually lead ingots - are 5 fitted around the upper rim of the reservoir, usually grouped in one position to effect a leading edge which then becomes the first section of the reservoir to be dragged under the water by the sheer weight of the ingots; (7) this use of weights fitted to the rim of the reservoir leads to a number of other disadvantages which include: (a) the increase in net weight of the vessel 10 reduces the water payload that can be carried; (b) poor flight characteristics are created; (c) damage to the reservoir fabric occurs through excessive loading at certain points; (d) the inherent imbalance of the reservoir causes the vessel to flip rapidly to one side resulting in the rigging lines attached to the top of the reservoir becoming entangled together and/or with other 15 hardware present to control the operation of the vessel; (e) leads to poor volume management as the reservoir normally is overfilled and the reduction in payload necessary to become airborne can only be achieved by either releasing the entire contents of the reservoir and attempting to refill the reservoir to a lesser degree or landing prior to filling and manually synching 20 the reservoir using a synch strap to carry a smaller payload. Accordingly, it is a general object of the present invention to overcome, or at least ameliorate, one or more of the above-discussed disadvantages. As a first aspect of the present invention, there is provided a device to assist the entry into and retaining of a liquid within a reservoir, said reservoir of the 25 type having a base, a substantially open top and a side wall connecting said top to said base, said reservoir being adapted to be filled with said liquid to a 3 required depth by immersing said reservoir in a body of said liquid, said device including: a support means essentially peripheral to a port that extends through said side wall or said base; and 5 a sealing means connected to said support means and adapted to move reversibly from a first closed position - sealing said port - to a second position inwards of said reservoir- opening said port - when the pressure exerted on said sealing means by said body of liquid exceeds the ambient pressure exerted on said sealing means within said 10 reservoir, and returns to said closed position when the pressure exerted on said sealing means by said liquid subsequently within said reservoir equals or exceeds the pressure exerted on said sealing means external of said reservoir. Preferably, said device is adapted to assist the entry of water into a reservoir. 15 As a second aspect of the present invention, there is provided a reservoir to hold liquid characterised in that said reservoir includes at least one said device as hereinbefore described. In one embodiment, said reservoir includes a multiple of said device. In those embodiments which include a multiple of said device, a said device 20 may be spaced laterally from an adjacent said device. In those embodiments which include a multiple of said device, a said device may be spaced vertically from an adjacent said device.

Preferably, said reservoir is an aerial-borne dump bucket of the type used in the release of water from said bucket over a forest. bush or similar fire. As a third aspect of the present invention, there is provided a method of filling a said reservoir with said liquid, said method including: 5 immersing said reservoir in a body of said liquid to a depth sufficient for said liquid to pass through said port of said at least one device to a required level within said reservoir; and subsequently removing said reservoir from said body of said liquid. A preferred embodiment of the present invention will now be described with 10 reference to the accompanying drawings, wherein: FIG. 1 is a schematic front view of a device of the present invention: FIG. 2 is a schematic side view of the device of FIG. 1; FIG. 3 is a schematic rear view of the device of FIGS. 1 & 2 when in a closed position; FIG. 4 is a schematic side view of the device of FIGS. 1 & 2 when in an open position; and FIG. 5 is a schematic cross-sectional view of two devices of FIGS. 1 to 4 installed in an aerial-borne fire-fighting dump bucket.

Referring now to the FIGS., the device (1) is fitted to a reservoir (13) of the type used as an aerial-borne dump bucket for water bombing bush fires. The device (1) includes complementary inner (2a) and outer (2b) peripheral frame members surrounding an open port (3) which extends through the side wall 5 (4) of the reservoir (13). Any convenient number of bolts (5) secure the inner and outer frames (2a,b) together. A plate (7) is pivotally attached to the inner surface of the inner frame member (2a) by a pair of suitable spaced pivot plates (8) and bolts (9) (FIGS. 2 & 3), A flexible membrane (11), substantially of complementary size to the plate (7), is fitted to that surface of the plate (7) 10 which faces the port (3). The dimensions of the plate (7) and membrane (11) are such that, when the device is in the closed position (FIG. 2), the membrane (11) is a liquid seal to the port (3). The plate (7) and membrane (11) are selected from any suitable material known in the art of sufficient weight to maintain the device (1) in this closed position when pressure on both 15 sides of the plate (7) are substantially equal, without the assistance of springs or any other tension-maintaining mechanisms, The upper edge (12) of the plate (7) is angled inwards sufficient to abut the inner frame member (2a) at an inclination when the device is in its maximum open position (FIG. 4) to prevent further inward movement of the plate (7). 20 In use (FIG. 5), for example, when the reservoir (13) is part of an aerial-borne bucket to be filled with water whilst attached to a helicopter, the water subsequently being dumped over a forest, bush or similar fire, the reservoir (13) is gradually lowered into a body of water, usually a lake, river or the sea. As the reservoir (13) is lowered, the hydraulic pressure subsequently exerted 2% by that body of water on the membrane (11)/plate (7) of the first lower device (1 a) exceeds the ambient pressure within the interior of the reservoir (13) and the membrane (11)/plate (7) moves inwards allowing water to enter through the port (3). As the reservoir (13) is continued to be lowered into the body of 6 water, the upper edge (12) of the plate (7) abuts the inner frame (2a) to prevent further movement of the membrane (11)/plate (7) as water continues to enter the reservoir (13). With the membrane (11)/plate (7) in its fully open position, the essential equality of the pressure exerted on those components 5 and, to a lesser extent, the inherent buoyancy of the membrane (11), the port (3) remains open as the reservoir (13) continues to be lowered into the body of water. A similar mechanism operates when the body of water reaches the second upper device (1b). When the required amount of water is in the reservoir (13), it is raised from the body of water. As the devices (1b), (1a) 10 become progressively exposed to the surrounding atmosphere, the higher pressure within the reservoir (13) being exerted by the water therein causes the respective membrane (11)/plate (7) to move to their closed positions, maintaining the membrane (11) in sealing contact with the port (3). The filled bucket is then flown to the required location and the water is released from the 15 reservoir (13) by opening any suitable valve(s) (14) known in the art for that purpose. The reservoir (13) is manufactured from any suitable flexible fabric-type material known in the art. The frame members 2(a,b), plate (7) and membrane (11) are also of any suitable material known in the art which can 20 be conformed to the curvature of the side wall or base of the reservoir (13) as required. This assists in significantly reducing the likelihood of any section of the device (1) becoming entangled with the rigging lines used to support the reservoir (13) under, for example, a helicopter. Further, the frame members 2(a,b) are manufactured from any suitable material known in the art that is 25 sufficiently rigid (a) to prevent slippage of the material of the reservoir (13) clamped between the frame members 2(a,b) when the reservoir (13) is filled with water; and (b) to avoid distortion of those frame members, and 7 consequently the membrane (11), when the reservoir (13) is full, thus maintaining the seal against the port (3). For a reservoir (13) of a larger volume, a multiple of devices (1) can be installed, preferably at different depths, to increase the rate of fill of the S reservoir (13) when immersed into a body of water. In such embodiments, when the multiple of devices are spaced vertically, each associated port (3) will progressively open as the water reaches each device (1) as the reservoir (13) is lowered into the water. The present invention offers a number of advantages which include: 10 the ability for a reservoir to be filled through both the normal valve used to fill that reservoir and through the instant device; the instant device decreases the fill time of the reservoir; multiple of the devices can be installed in a reservoir which all operate identically irrespective of their positions in the reservoir; 15 the instant device adds insignificantly to the overall weight of the reservoir and does not cause undue wear on the material(s) from which the reservoir is manufactured; and the instant device, when used in an aerial-borne water dump bucket, 20 enables the operator of the aircraft to maintain a level plane whilst filling the bucket; the bucket can be filled from very confined dams and the like as the bucket does not tip during filling; the net and gross weights of the bucket are not effected as installation of weights to assist 8 buoyancy whilst filling are not required; the absence of these weights also avoids adverse flight characteristics of the aircraft as the overall, weight of the filled bucket is more evenly distributed; rigging attached between the bucket and aircraft are less likely to become entangled as 5 filling is now undertaken vertically; the aircraft operator can better determine the volume of water in the bucket as the bucket is level during filling and can be lowered as much or as little as required by the operator. It will be appreciated that the above described embodiments are only 10 exemplification of the various aspects of the present invention and that modifications and alterations can be made thereto without departing from the inventive concept as defined in the following claims.

Claims

1. A device to assist the entry into and retaining of a liquid within a reservoir, said reservoir of the type having a base, a substantially open top and a side wall connecting said top to said base, said reservoir 5 being adapted to be filled with said liquid to a required depth by immersing said reservoir in a body of said liquid, said device including: a support means essentially peripheral to a port that extends through said side wall or said base; and a sealing means connected to said support means and adapted 10 to move reversibly from a first closed position - sealing said port to a second position inwards of said reservoir - opening said port - when the pressure exerted on said sealing means by said body of liquid exceeds the ambient pressure exerted on said sealing means within said reservoir, and returns to said closed position 15 when the pressure exerted on said sealing means by said liquid subsequently within said reservoir equals or exceeds the pressure exerted on said sealing means external of said reservoir.

2. A device as defined in Claim 1 wherein, said device is adapted to assist 20 the entry of water into said reservoir.

3. A reservoir to hold liquid characterised in that said reservoir includes at least one said device as defined in Claim 1 or Claim 2. 10

4. A reservoir as defined in Claim 3 which includes a multiple of said device.

5. A reservoir as defined in Claim 4 wherein, a said device is spaced laterally from an adjacent said device. 5

6. A reservoir as defined in Claim 4 wherein, a said device is spaced vertically from an adjacent said device.

7. A reservoir as defined in any one of Claims 3 to 6 which is an aerial borne dump bucket of the type used in the release of water from said bucket over a forest, bush or similar fire. 10

8. A method of filling a reservoir as defined in any one of Claims 3 to 7 with said liquid, said method including: immersing said reservoir in a body of said liquid to a depth sufficient for said liquid to pass through said port of said at least one device to a required level within said reservoir; and 15 subsequently removing said reservoir from said body of said liquid.

9. A device substantially as herein described with reference to the accompanying drawings.

10. A reservoir substantially as herein described with reference to the 20 accompanying drawings. 11

11. A method substantially as herein described with reference to the accompanying drawings.