GB2331796A

GB2331796A - Inflatable bladder valve

Info

Publication number: GB2331796A
Application number: GB9825774A
Authority: GB
Inventors: David John Cole
Original assignee: ENVIROVALVE Ltd
Current assignee: ENVIROVALVE Ltd
Priority date: 1997-11-27
Filing date: 1998-11-26
Publication date: 1999-06-02
Anticipated expiration: 2018-11-26
Also published as: GB2331796B; GB9724988D0; GB9825774D0

Abstract

The invention provides a fluid control valve comprising a bladder and means for inflating the bladder so as to close, or substantially close, a pipe or duct. The bladder 106 can be inflated from a pressurised fluid source via pressure control valve 114 which is float operated. When the float rises the means 114 may open to cause the bladder to be inflated and when it falls the bladder may be connected to the exhaust by the means 114. Alternatively, in different circumstances, the reverse arrangement may be useful. The bladder may be used where an associated fluid outlet allows diversion of flow from the pipe or duct when the bladder is inflated. The bladder may be inflated from a manual pump or a gas cylinder.

Description

1 VALVE 2331796 The invention relates to a low pressure fluid control

valve for diverting or restricting a flow of fluid for example in domestic plumbing applications and sewage systems. The invention also finds application in industrial drainage and effluent control systems.

According to one aspect of the invention there is provided a fluid control valve comprising a bladder, means for operably positioning the bladder in a pipe or duct and means for inflating the bladder substantially to fill the cross-sectional area of the pipe or duct thereby to restrict flow of fluid through the pipe or duct. Beneficially, a fluid outlet can also be provided for diverting the flow of fluid when the bladder is inflated.

The means for inflating the bladder can comprise a manually operated pump for example, such as a bicycle pump, or a hand operated bladder comprising a flow control valve.

According to a preferred form of the invention for industrial sewage or drainage systems, the inflating control means can comprise a pressurised gas cylinder actuated manually by a depressable knob for t 2 example or automatically such as by a float valve to pressurise or depressurise the bladder. 'Ite fluid used to inflate the bladder can be a gas such as carbon dioxide, or a liquid foam for example if the inflation is to last any length of time.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

Figures 1,2,3 and 4 are side elevation views of a first embodiment of a control valve according to the invention in different states of operation; Figures 6,7 and 8 are elevation views of a second embodiment of a valve according to the invention; Figures 9 and 10 are side elevation view of a third embodiment of part of a valve according to the invention; and Figures 11 and 12 are side elevation views of a fourth embodiment of part of a valve according to the invention.

3 Figures 13 and 14 are a perspective view and sectional diagranunatic elevation of a fifth embodiment.

Referring to figures 1 to 4 there is shown a valve 10 according to the invention comprising a body portion 12 and pipe connectors 14 and 16 at each end. Connectors 14 and 16 enable valve 10 to be connected to existing pipes P such as the waste water downpipe from a domestic bath for example. They can be push-fittings comprising gaskets or 0-rings for C5 zn example. Valve 10 further comprises an inflatable bladder 18, such as a rubber balloon, which bladder 18 is attached at an inlet collar 20 to one side of body portion 12 and at a holding collar 22 on the opposite side of body 12. Part of bladder 18 protrudes beyond collar 22. An overflow outlet 24 is provided for diverting the flow of fluid F when bladder 18 is inflated as shown in figure 2. In that configuration, bladder 18 fills the cross-sectional area of body portion 12 instead of extending merely diametrically thereby to restrict flow of fluid S beyond the bladder. The build up of fluid above the bladder causes the fluid to exit at overflow 24.

Accordingly, fluid can be directed to a different location. In the case of domestic waste water, for example bath water, this can be diverted for use in watering a garden via outlet 24. Figure 4 shows a tube 26 0 Z 4 connecting a hand pump 28 to inlet 20 of bladder 18. Figure 5 shows a plan view of the bladder 18 in a deflated and merely diametric state as shown in figure 1. Fluid can accordingly flow around bladder 18 in this configuration.

Referring to figures 6,7 and 8, there is shown a valve 40 comprising an nonreturn valve 42, connector 44, locking ring 46, 0-ring 48, and bladder cartridge 50. There is further provided an 0-ring 52 which operably sits on ledge 53 within a collar 54. Collar 54 further comprises an inner threaded portion 56 and is attached to a resilient clamping device 58. Valve 40 is assembled by positioning 0-ring 52 on ledge 53, lowering cartridge 50 above 0-ring 52 and clamping it in position by fastening locking ring 46 into threaded region 56 of collar 54 thus compressing 0-ring 48 between locking ring 46 and cartridge 50, and 0-ring 52 between cartridge 50 and ledge 53. Connector 44 and non return valve 42 provide an inlet for fluid such as pressurised gas into C> cartridge 50 thereby to enable inflation of a bladder 60 held therein.

Figures 7 and 8 show respectively a cross sectional view of a valve 40 attached to a pipe P, wherein bladder 60 is in a deflated and inflated state respectively. Inflation of bladder 60 can be actuated for example by connecting a pressurised gas cylinder to non-return valve 42 and actuating a depressible button or other device in order to effect transfer of gas into bladder 60. Bladder 60 thereby inflates leaving cartridge 52 and filling a cross-sectional region of pipe P thereby to restrict flow of fluid in direction F shown in figure 8.

Such a fluid control valve is particularly beneficial in industrial applications where a pipe P for effluent drainage can be exposed and an aperture A created therein to allow entry for bladder 60 into the pipe. The valve 40 can be clamped to the pipe by resilient clamping device 58 comprising an open-ended cylindrical structure cut along its longitudinal surface to provide a C-shape in cross-section.

The resilient device 58 can therefore clamp over the sides of pipe P and enable positioning of collar 54 and cartridge 50 above aperture A. In the event of accidental spillage of toxic fluids such as oils or acids in an industrial workshop or factory, valve 40 can be actuated to inflate bladder 60 thereby to prevent passage of toxic fluid through pipe P which might lead to a public sewage system or river for example. Accordingly, a company can mitigate against passing toxic fluid into the public water t> system and thereby avoid payment of significant fines.

6 In another embodiment of the invention shown in figures 9 and 10, a valve 70 comprises a connector 44, locking ring 46, 0-ring 52, collar 54 and clamping device 58, substantially similar to device 40. However, in valve 70, connector 44 is connected directly to a bladder 72 which depends from connector 44 but in a non-inflated ftate does not significantly inhibit flow of fluid through pipe P.

Bladder 72 can be pre-shaped to rest against the upper surface of a pipe P even in its deflated state. When inflated for example using a pressurized fluid canister or a hand pump, bladder 72 inflates to fill the cross-sectional area of pipe P thereby to restrict flow of fluid through the pipe.

In a further embodiment of a valve according to the invention, (figures 11, 12) valve 80 comprises a bladder 82 connected to a inflation device by a tube 84. Tube 84 merely has to pass through a small aperture in pipe P to provide access to an inflation device such as a hand pump or pressurized fluid canister. In normal use, bladder 82 is sufficiently small so that it does not restrict flow of fluid through pipe P but when inflated as shown in figure 12, can fill the cross-sectional area of pipe P thereby to restrict flow of fluid therethrough.

7 In the fifth embodiment shown in figures 13 and 14, the system of the invention is installed in a collection pit intended to catch spilt fluid. The pipe 100 drains the pit and may extend to a public sewer or to effluent control equipment. The invention is used to control flow into the pipe 100 from the pit.

Turning to figure 14, the valve comprises a body 102 closed by cap 104. Bladder 106 lies in a housing 108 held in position in the body by a spacer sleeve I 10. The bladder is connected by supply line 112 to control means 114 which is connected in turn both to a supply line from the source of fluid pressure 116 and to exhaust for example into ambient atmosphere 118.

In this embodiment the valve is controlled by float 120 carried on arm 122 pivoted on a cross-pin (124) on the cap 104.

The intention here is that when the liquid level in the chamber or pit, generally indicated by the reference 126 rises from the sloping floor 128 the float will actuate the means 114 to allow flow of pressurising fluid to inflate the bladder and thereby close the pipe 100. When the float falls, the means 114 may automatically revert to a condition in which it 8 allows the bladder to deflate and reopen the pipe.

The bladder maybe arranged so that it effects incomplete closure of the pipe so as to allow a controlled rate of flow along the pipe. This may be significant in industrial situations where an effluent discharge of a low or intermittent rate may be permissable but where a continuous or large volume discharge may be impermissible. However, control of discharge rate may additionally or alternatively be effected by the relative position of the float within the pit or chamber 126 in that when the liquid level in the chamber is sufficiently low that the float hangs freely, the bladder maybe deflated to allow that volume to drain freely through the pipe. When the volume in the chamber is sufficient that the float valve is raised, the reduced rate of flow will occur.

The limit flow rates may be achieved by providing a bladder which when fully inflated does not occupy the total volume of the pipe, or by alternative means.

One possibility, not shown in the drawings, is to provide a pressure limiting valve in the pipe supplying the bladder, and this possibility exists in all of the described embodiments. The limit may normally be set to a 9 condition in which the bladder can be inflated to completely close the pipe in question, or may be set to a lower figure allowin a controlled rate of ty 9 flow past the bladder.

Alternatively, the means 114 may be arranked so that when the level is low and the float valve is ineffective, the bladder is in the inflated condition allowing limited flow through the pipe, but when the float valve is actuated by rising liquid level the bladder is deflated to allow increased flow through the pipe.

C Suitable materials for manufacture of the bladders are elastomers which have a suitable tensile strength, elongation and temperature resistance characteristics, depending on the application. It is also preferable that the elastomer is resistant to oil and grease and such an elastomer is butadiene acrylonitrile. Other suitable elastomers with good all round properties are polychloroprene, Fluorosilicone and polysulphide. Where there is no risk of contact with oil or grease, suitable elastomers are natural rubber, butadiene styrene and polypropylene oxide (PPO).

Claims

1. A fluid control valve comprising a bladder, means for operably positioning the bladder in a pipe or duct and means for inflating the bladder substantially to fill a cross-sectional area bf the pipe or duct thereby to restrict flow"of fluid through the pipe or duct.

2. A valve as claimed in claim 1 wherein a fluid outlet is associated with the bladder allowing diversion of flow from the pipe or duct when the bladder is inflated.

3. A fluid control valve as claimed in claim 1 wherein the bladder is arranged to allow a controlled flow past the bladder when inflated in the pipe or duct.

4. A control valve as claimed in any of claims 1-3 where the bladder is provided or associated with a manually operated pump.

5. A control valve as claimed in any of claims 1-3 wherein the bladder is associated with a pressurised gas cylinder for bladder inflation.

11

6. A control valve as claimed in any preceding claim wherein the bladder is connected to a fluid pressure control valve.

7. Fluid control valve as claimed in claim 6 wherein the pressure control valve is arranged to be float-actuated.

8. A fluid control valve substantially as described and with reference to any of the accompanying drawings.