GB2311360A

GB2311360A - Float operated flow control valve

Info

Publication number: GB2311360A
Application number: GB9626110A
Authority: GB
Inventors: John Charles Barker
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-03-23
Filing date: 1996-12-16
Publication date: 1997-09-24
Also published as: GB9626110D0; GB9606164D0

Abstract

A valve body 13 is coupled to a float 1 via a pivoted arm 10. The float has a sealed buoyancy chamber 2 and an open-topped liquid chamber 3 provided with a restricted outlet 6, 7. The valve controls flow of liquid from a port 16 into the chamber 3 so that when the float falls with a level of liquid 17 the weight of liquid in the chamber 3 causes the float to drop to a relatively low level. The filling rate is therefore increased. When the water level rises and flow stops, the chamber 3 drains through the holes 6 and 7 so that the float rises relative to the liquid level 17 and produces a swift, noise-free termination of flow. The arm 10 is arranged to conduct liquid from the valve outlet to the chamber 3.

Description

FLOAT-OPERATED FLOW CONTROL VALVE TECHNICAL FIELD OF THE INVENTION This invention relates to float-operated valves, and in particular, but not exclusively, those used in reservoirs where it desirable for the entry of liquid to be controlled by the volume of liquid in said reservoir.

BACKGROUND In the main, floats and valves are arranged in such a way that when the fluid level drops in a reservoir the float will faithfully follow the fluid level causing the valve to open simultaneously. The operation of such known valves is to a large extent determined by the size and shape of the float. Changes in operation are generally brought about by the design of the valve or changes in the mechanical advantage between the valve and float.

An aim of the present invention is to provide a new and improved form of float-operated valve.

SUMMARY OF THE INVENTION The present invention proposes a float-operated flow control valve comprising a valve body having an inlet port and an outlet port for liquid, a valve member being movable within the valve body to co-operate with a seat to control flow of liquid through the valve body, an operating linkage movably connected to the valve body and carrying a float arranged to move up and down with a level of liquid, said linkage being operably arranged to permit the valve member to sealably co-operate with the seat such as to cut off the flow of liquid through the valve body when the float rises, and in which the float comprises a sealed buoyancy chamber and a liquid chamber which is arranged to receive liquid flowing from the outlet port, the liquid chamber including outlet means which permits liquid to drain from the said liquid chamber at a controlled rate.

BRIEF DESCRIPTION OF THE DRAWINGS The following description and the accompanying drawings referred to therein are included by way of non-limiting example in order to illustrate how the invention may be put into practice. In the drawings: Figure 1 is a general view of a float-operated flow control valve in accordance with the invention.

DETAILED DESCRIPTION OF THE DRAWINGS Referring to Fig. 1, the valve is mounted in a cistern or other container to control the filling of the container with water (or for that matter any other liquid). The main problems of known assemblies of this nature pertain to achieving a positive opening and closing of the valve without hissing and similar noises produced by water flow.

A valve body 13 has a water inlet port 20 and contains a valve body (not shown) which co-operates with a valve seat in known manner to control the flow of liquid into the container yia a pipe 15. The pipe 15 is arranged to discharge through an outlet port 16 above an arm 10 which is pivoted to the valve body at 14 for angular movement in a substantially vertical plane. The arm is formed as an upwardly open channel 11 and, as shown, is straight, although it could also be cranked horizontally and/or vertically provided there is generally a downward slope away from the valve body.

At the remote end of the arm 10 is mounted a float 1. The float is generally of upright cylindrical shape, although other shapes are possible. The bottom part of the float is partitioned off by walls 4 and 5 to form a sealed buoyancy chamber 2, above which there is an open-topped liquid chamber 3. The chamber 3 is provided with a drainage hole 6 in the bottom of its side wall, and a larger outlet hole 7 is provided at a higher level in the side wall. As shown, the hole 7 is in the form of an axial slot, although other shapes are possible.

When the valve in body 13 is open, water flows from pipe 15 into the channel 11 and thence flows into the liquid chamber 3 before passing into the container.

In use, starting with the water at its highest level, the valve will be held closed by a push rod or like projection (not shown) on the arm 10. The float 1 is thus in the position as shown in Figure 1, by virtue of the body of water in the container applying force to float 1 due to the buoyancy chamber 2. When the water level 17 drops, e.g. due to water being drawn off from the container, the float 1 will fall with the water level 17 in direction B. As this takes place the push rod will allow the valve to open under pressure of water which flows into the valve in direction A, through the pipe 15 and down the channel-shaped arm 10 to enter the chamber 3.

The flow of fluid into the chamber 3 is initially greater than can flow from hole 6 and slot 7 so that chamber 3 will fill with water and eventually overflow.

In this condition the weight of water in the liquid chamber 3 acts to increase the weight of the float so that the float sinks to a low level in the water and ensures that the valve is held fully open. The rate at which the container fills may thus be greater than with normal float-operated valves.

As the container fills with water the water level 17 will again rise in direction C, thereby lifting the float and starting to close the valve. Eventually the.flow of fluid from channel 11 becomes less than that flowing from slot 7 whereupon float 1 will rise in a steady stable fashion until the valve becomes fully closed.

However, water continues to flow from hole 6 and slot 7, and in doing, allows the buoyancy of the float to steadily increase until the chamber 3 is completely empty. This causes additional closing pressure to be applied to the valve body and ensures a swift and effective termination of flow.

Amongst other advantages of this configuration is a positive stable action of float 1 on the valve 13, with the result that noises caused by fluid flow during filling are substantially reduced or eliminated.

It will be appreciated that the arm 10 need not conduct water to the float chamber 3. The pipe 15 could, instead, be arranged to discharge directly into the float chamber.

Changes in the operating characteristics of the float-operated valve can easily be achieved by altering the relative size, shape and number of the outlet holes 6 and 7.

Whilst the above description lays emphasis on those areas which, in combination, are believed to be new, protection is claimed for any inventive combination of the features disclosed herein.

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Claims

CLAIMS 1. A float-operated flow control valve comprising a valve body having an inlet port and an outlet port for liquid, a valve member being moveable within the valve body to co-operate with a seat to control flow of liquid through the valve body, an operating linkage movably connected to the valve body and carrying a float arranged to move up and down with a level of liquid, said linkage being operably arranged to permit the valve member to sealably co-operate with the seat such as to cut off the flow of liquid through the valve body when the float rises, and in which the float comprises a sealed buoyancy chamber and a liquid chamber which is arranged to receive liquid flowing from the outlet port, the liquid chamber including outlet means which permits liquid to drain from the said liquid chamber at a controlled rate.
2. A flow control valve according to Claim 1, in which said outlet means is arranged to permit the liquid chamber to substantially drain free of liquid.
3. A flow control valve according to Claim 1 or 2, in which the operating linkage comprises an arm which is pivotally coupled to the valve body for angular movement in a substantially vertical plane.
4. A flow control valve according to Claim 3, in which the said arm operates the valve member via a push rod.
5. A flow control valve according to Claim 3 or 4, in which said arm is arranged to conduct liquid from the outlet port to the liquid chamber.
6. A flow control valve according to any of Claims 1 to 4, in which said outlet port is disposed above said liquid chamber.
7. A flow control valve according to any preceding claim, in which the liquid chamber has an open top.
8. A float-operated flow control valve substantially as described with reference to the drawings.