GB2281769A

GB2281769A - Float operated valve

Info

Publication number: GB2281769A
Application number: GB9414633A
Authority: GB
Inventors: Barbara Holloway
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-09-04
Filing date: 1994-07-25
Publication date: 1995-03-15
Anticipated expiration: 2014-07-25
Also published as: GB2281769B; GB9414633D0

Abstract

A float valve for controlling the flow of slurry/dirty water comprises a duct or housing defining a flow port (1, 21) and a valve seat (2, 22), and a valve closure member (3, 23). The closure member has the form of a ball (3, 23), a conoid or a cylindrical or other curved-surface member and is mounted for movement towards and away from the valve seat (2, 22). Float means (7, 27) are provided for moving the valve closure member (3, 23) between the open and closed positions. The closure member may be rotatably mounted on an axle carried on a pair of spaced apart arms 4a and may have a non-stick coating. The closure member is preferably made of a resilient material e.g. rubber. <IMAGE>

Description

A FLOAT VALVE The present invention relates a float valve and particularly although not exclusively to a valve suitable for use in the control of the flow of slurry/dirty water from a slurry store into a reception pit.

It has recently become common practice to store agricultural slurry/dirty water in an above-ground storage tank and to have a reception pit adjacent thereto so that the contents of the pit may be pumped into the tank or the pit may be filled from the tank via an outlet pipe. A float valve is provided in the outlet pipe to control the flow of slurry/dirty water from the tank. If the valve malfunctions e.g. by becoming blocked, or if the operator fails to close the valve of if the pipe becomes blocked, there is a danger the slurry will overflow from the pit and cause serious damage.

In International Patent Specification Wo 94/05146 of G. & W. Lea (Nantwich) Ltd., which was published on 17 March 1994 (i.e. after the priority date of the present application) and has a priority claim of 5 September 1992, a pipe or housing is disclosed having a cylindrical concave lower end or valve seat and a closure member with cylindrically concave surface is pivotally mounted and displaceable by a float so that a straight edge moves across the valve seat to open and close the valve.

It is an object of the present invention to provide a float valve particularly suitable for controlling the flow of agricultural slurry/dirty water.

According to the present invention a float valve for controlling the flow of slurry/dirty water comprises a duct or housing defining a flow port and a valve seat, a valve closure member in the form of a round ball, a sphere or other conoid, cylindrical or other curved surface member, mounted for movement towards and away from the valve seat respectively between a closed position in which the port is closed by the curved surface moving into the port and into contact with the seat and an open position in which the port is open, and float means for moving the valve closure member between the open and closed positions.

It will be appreciated that the valve closure member does not present an edge moving solely across the seats as in "Lea" but rather moves partly into the port and into contact with the valve seat to close the valve in effect to plug or stop the flow port to provide for advantageous closure.

The valve seat may be provided at or simply comprise the end of a preferably rectilinear pipe portion which is preferably of circular cross section with the end lying in a plane at right angles to the central axis of the pipe or preferably the end is inclined to the central axis at preferably 45" and preferably said portion extends downwardly so that the inclined seat lies at 450 or substantially 45" to the vertical.

The valve closure member is preferably a round ball or sphere and preferably solid and preferably of resilient material such as rubber and the surface of the ball and of the seat will be complimentary to each other to provide good sealing.

The wall of the ball forms the closure means.

Preferably the closure member will be rotatably mounted and preferably such as to rotate on a spindle to provide easy passage for solids in slurry/dirty water flowing through the valve. Thus, if an obstruction occurs at a side of the closure member it will tend to rotate to free such and facilitate the closing.

The closure member, such as a sphere may be smaller relative to the edge of the valve seat to produce an improved plugging action as the closure member moves towards the valve to close the valve.

Preferably the outer circumference of the closure member is of about 10% larger than the circumference of the seat.

The valve closure member is preferably rotatably mounted on support means which are preferably in the form of two spaced apart arms or a bifurcated arm carrying an axle or other pivot mounting means for the closure member and said support means is preferably pivotally mounted on said housing or on one or more extension or spacing members mounted thereon. The support means is preferably rigidly connected to one or more float support arms so as to be displaceable therewith to open and close the valve. The float means or member may be of any suitable shape such as cylindrical, spherical or any other suitable shape and is preferably hollow. The float member is such as to float on the surface of the slurry/dirty water and to move up and down with that surface - thereby pivoting the valve closure member between open and closed positions.The float member may be provided with a nonstick surface, such as polytetrafluoroethylene or the like, to reduce any tendency of matter to stick thereto.

The invention will be described further, by way of example, with reference to the accompanying drawings, in which: Fig. 1 is a perspective view of float valve forming a first embodiment according to the invention; Fig. 2 is a side elevational view of the float valve of Fig. 1 in the fully open position; Fig. 3 is a side elevational view of the float valve of Fig. 1 in the fully enclosed position; Fig. 4 is a schematic illustration of the valve of Figs. 1 to 3 in a typical installation; Fig. 5 is a perspective view of float valve forming a second embodiment according to the invention; Fig. 6 is a side elevational view of the float valve of Fig. 5 in the fully open position; and Fig. 7 is a side elevational view of the float valve of Fig. 5 in the fully closed position.

A float valve is illustrated in Figs. 1 to 3 and comprises a tubular duct or housing 1 defining a valve flow port through which slurry/dirty water is to pass from a storage tank (not shown). The housing 1 is formed with a cylindrical end portion with a circular end face 2 lying in a plane at right angles to the central longitudinal axis of the cylindrical end portion and which end face effectively forms the valve seat of the valve.

A valve closure member in the form of a ball 3 is rotatably mounted on two spaced apart mounting arms 4 (only one shown) secured to housing 1 and extending therebelow for the mounting of the ball 3 and thereabove for supporting a spray limiting shield 5. Ball 3 is pivotally mounted on two spaced apart ball support arms 4A (only own shown to any degree) which are fixedly connected at their lower ends to move with float support arms 6 and both ball support arms 4 and float support arms 6 are pivotally mounted at the lower ends of the mounting arms 4. A buoyant float illustrated as a spherical ball 7 is rotatably mounted on arms 6 and is complimentary in shape to the surface of the valve seat 2.

The float 7 is disposed to float on the surface of the slurry/dirty water in a slurry pit 10 as shown in Fig. 4. The pit 10 is disposed adjacent a slurry storage tank 11. A pipe 12 leads from the pit 10 to the top of the tank and a motor driven pump 13 is provided for pumping slurry/dirty water from the pit through the pipe 12 into the tank 11. A further pipe 14 is provided leading to the pump 13 to enable slurry/dirty water to be pumped into a tanker. Tankers would normally be driven up to the pit 1 by means of tractors. The pit 10 is filled from the tank 11 via an outlet pipe 15 and the valve described with reference to Fig. 1 is disposed on the outlet end of pipe 15.

A grid 16 closes off the top of the pit 10. The float valve operates automatically to maintain the level of slurry/dirty water in the pit at a predetermined level. When the flow valve is open (as shown in Fig.

2), slurry/dirty water flows out through pipe 15. As the level of slurry/dirty water in the pit rises, so also does the float 7, which is floating on the surface.

This in turn rotates valve closure member or ball 3 to progressively close the flow valve. The closure valve or ball 3 being rotatably mounted acts to avoid or reduce the likelihood of blocking since it acts as a rotating plug diverting solid matter such as straw between it and the valve seat 2.

The float valve may be made of metal or synthetic plastics materials. To resist any tendency of the slurry/dirty water to stick to the ball 7 and/or 27 and thereby impair their function, the ball(s) may be coated with a non-stick material such as polytetrafluoroethylene.

In Figs. 5 to 7 an alternative and preferred embodiment is illustrated wherein instead of a horizontal end to housing 1 with spray shield as shown in Fig. 1, the end portion of the housing extends downwardly and the valve seat is inclined to the axis thereof. Thee float valve (18) comprises a tubular duct or housing 19 having a horizontal portion 20 and a vertically, downwardly extending portion 21 defining a valve port through which slurry/dirty water is to pass.

The portion 21 is of a cylindrical cross section and has an inclined end face (22) which effectively form the 45O valve seat (22). A valve closure member in the form of a ball 23 is rotatably mounted on two support arms 24A which are pivotally mounted on two mounting arms 24 extending beneath the housing 19. The two support arms 24A (only one of which is fully visible in Fig. 1) are connected to the downwardly extending portion 21 of housing 19. Ball 23 is rotatably mounted on arms 24A and is complimentary in shape to the end surface of portion 21 forming the valve seat 22. The two mounting arms 24A are fixed to the float support arms which have a buoyant float in the form of a ball 27 rotatably mounted at their ends.The arms 24A and 26 are pivotally mounted at the lower end of the mounting arms 24 so that displacement of the float upwardly causes the ball 23 to seat in seat 22 and close the valve 18 or open it in the opposite direction.

The float 27 is disposed to float on the surface of the slurry/dirty water in a slurry pit 10 in similar manner as shown in Fig. 4. The valve closure in the form of ball 27 also acts as a rotating plug diverting solid matter such as straw between it and the valve seat 22 to reduce the likelihood of blockages.

The float valve 19 may be made of metal or synthetic plastics materials. To resist any tendency of the slurry/dirty water to stick to the ball 23 and/or 27 and thereby impair it/their function, the ball(s) may be coated with a non-stick material such as polytetrafluoroethylene.

It will be appreciated that part of the valve closure member such as ball 3 or 23, moves towards and away from the valve seat and moves into and out of the space defined by the valve seat (2 or 22) rather than moving solely across the face thereof and as such effects a partial plugging action which enhances the closing action. It has been found that if the closure member has an effective diameter approximately 10% larger than that of the seat, a good closing action is achieved. The closure member may be hollow but is preferably a solid member but in any event of slightly resilient material and may be made of, for example, rubber or the like.

The support arms 4A,24A are mounted and of such dimension so that as float 7,27 is raised they cause the member 3,23 to locate on the seat 2,22. The mounting means 4,24 have the pivot mounting or parallel to the central axis of portion 21 to enable location of the closure member 3,23 on its respective seat. The port end and seat may be one and the same.

It will be appreciated that the above embodiments have been described by way of example only and that many variations are possible without departing from the scope of the invention. For example, the shapes of the valve seat, the valve closure member and the float may be changed as desired to any spherical, hemispherical or other conoid, cylindrical or other curved surface. The float may be spherical or any other suitable shape.

Claims

1. A float valve for controlling the flow of slurry/dirty water comprising a duct or housing defining a flow port (1,21) and a valve seat (2,22), a valve closure member (3,23) in the form of a round ball (3,23), a sphere or other conoid, cylindrical or other curved-surface member, mounted for movement towards and away from the valve seat (2,22) respectively between a closed position in which the port is closed by part of the curved surface member (3,23) moving into the port (1,21) and into contact with the seat (2,22) and an open position in which the port (1,21) is open, and float means (7,27) for moving the valve closure member (3,23) between the open and closed positions.

2. A valve as claimed in claim 1, in which the valve seat (2,22) is at the end of a rectilinear pipe portion (1,21) of circular cross section with the end or seat (2,22) lying in a plane at right angles to the central axis of the pipe (1,21) or inclined to the central axis.

3. A valve as claimed in claim 2, in which the seat (22) is inclined at 450 to the central axis of the pipe portion (21) which extends downwardly preferably said portion extends downwardly so that the inclined seat lies at 45" or substantially 45" to the vertical.

4. A valve as claimed in any of claims 1 to 3, in which the valve closure member is a round ball or sphere (3,23).

5. A valve as claimed in any of claims 1 to 4, in which the valve closure member (3,23) is solid or hollow and of resilient material such as rubber and the surface of the ball and of the seat will be complimentary to each other to provide good sealing.

6. A valve as claimed in any of claims 1 to 6, in which the valve closure member (3,23) is rotatably mounted to be rotatable about a central axis thereof.

7. A valve as claimed in any of claims 1 to 6, in which the closure member (3,23) is smaller relative to the valve seat to produce an improved plugging action as the closure member moves towards the valve to close the valve and preferably the outer circumference of the closure member is of about 10% larger than the circumference of the seat.

8. A valve as claimed in any of claims 1 to 8, in which the valve closure member (3,23) is rotatably mounted on support means (4A,24A) which are preferably in the form of two spaced apart arms (4A,24A) or a bifurcated arm carrying an axle or other pivot mounting means for the closure member.

9. A valve as claimed in claim 8, in which said support means (4A,24A) is pivotally mounted on said housing (1,21) or on one or more extension or spacing members (4,24) mounted thereon.

10. A valve as claimed in claims 8 or 9, in which the support means (4A,24A) is rigidly connected to one or more float support arms (6,26) so as to be displaceable therewith to open and close the valve.

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