GB1563331A - Flow control device - Google Patents

Description

(54) FLOW CONTROL DEVICE (71) We BAILEY GILL PRODUCTS LIMITED, formerly known as WILLIAM BAILEY (BIRMINGHAM) LIMITED, a British Company, of Noose Lane, Willenhall, Staffordshire do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to rising spindle fluid flow control valves.

In rising spindle taps it is conventional practice to provide the washer on a jumper which is formed separately from the spindle and is carried thereby in a manner permitting its rotation relative to the spindle. The jumper usually has a stub shaft extending into a blind, axial bore in the end of the spindle. Suitable arrangements must then be made to retain the jumper shaft in the spindle bore. These usually comprise projections on the spindle extending into grooves in the jumper shaft.

The present invention provides a fluid flow control valve including a valve seat and a valve closure member that is movable towards and away from the valve seat by rotation of a spindle, about its axis, connected to the valve closure member, the end face of the spindle nearer to the closure member being flat and the closure member comprising or being attached to an element having a resilient socket with a flat base, an end portion of the spindle being a snapfit within the socket with the flat face of the spindle facing the flat base of the socket, and the spindle being rotatable about its axis relative to the closure member.

The said element may comprise an integral sealing surface for forming a seal against the valve seat when the valve is in its closed position. Alternatively, the element may have attached thereto a separately formed sealing washer for forming a seal against the valve seat when the valve is in its closed position.

In the latter embodiment, the sealing washer is preferably attached to the element by conventional means, for example a "fir-tree" which may be formed integrally with the element.

The socket preferably comprises a plurality of radially separable members and may have one or more inwardly directed projections which engage, as a snap fit, an external shoulder on the spindle. The or each projection may be in the form of a flange and the external shoulder may be part of a circumferential recess formed in the spindle.

If desired, the element may have guide means for guiding axial movement thereof relative to the spindle. For example, the element may have a shaft that projects into an axial bore in the spindle.

In the case where the element has an integral sealing surface, the element may be made of a suitable resilient plastics material, for example Kematal (Registered Trade Mark), Nylon (Registered Trade Mark), polypropylene or ABS. In the case where there is a separately formed sealing washer, the element may be made of a plastics material, for example Kematal.

A thrust bearing member or a wear resistant member may be interposed between the said end face of the spindle and the base of the socket.

By way of example, two embodiments of the invention will now be described with reference to the accompanying diagrammatic drawings in which: Figure 1 shows a partially sectioned elevation of the end of a spindle of a rising spindle tap in accordance with the invention, Figure 2 shows a plan view of the washer mounting element shown in Figure 1, and Figure 3 shows an assembly of a spindle and a washer snap fitted directly thereon.

The spindle shown in Figure 1 comprises an externally screw threaded portion 10 adapted to co-operate with corresponding screw threads provided in the body of a conventional rising spindle tap. An externally smooth portion 12 of the spindle extends away from the portion 10, through a packed gland in the body of the tap. Projecting away from the portion 10 in the opposite direction to the portion 12 is a portion 14 the end face of which is flat and which receives a washer mounting 16 to be described further below. Portion 14 comprises an external groove 18 between the screw threaded portion 10 and an end flange 20 on the spindle.

Washing mounting 16 comprises a disc 22 provided on one of its faces with a conventional integral firtree 24. In use, a conventional washer can be snapped over the projecting flange on the firtree to be retained between that flange and the disc 22. On its face opposite flrtree 24, disc 22 is provided with socket 26 having a flat base, the walls of which socket have a degree of radial resilience. This resilience may be due solely to the material from which the socket is made, or may be increased by the provision of radial slits 28 indicated in dotted lines in the plan view shown in Figure 2. In the following description, it will be assumed that such slits are unnecessary.

The wall of socket 26 has an inwardly projecting flange 30 at its end remote from the disc 22. Due to the radial resilience of the socket, flange 30 can be expanded radially as the mounting 16 is forced axially of the spindle as viewed in Figure 1. Thus, flange 30 will snap over flange 20 on the spindle to lie in the groove 18 on the spindle and retain the washer mounting thereon.

The dimensions of the socket in relation to the dimensions of the flange 20 are such that the mounting 16 can rotate relative to the spindle.

It may be required that the mouting 16 be given positive guidance relative to the spindle in case it becomes detached from the spindle in use. If so, the mounting may have an integral stub shaft 32 indicated in dotted lines on the drawings. This shaft may be located in a corresponding aligned bore 34 in the end of the spindle. Thus, if the mounting 16 does become detached, shaft 32 will remain in bore 34, so that the mounting can move only axaially of, and rotationally about the vertical longitudinal axis of the spindle.

The mounting 16 is preferably moulded from a plastics material, for example that sold by ICI under the trademark "Kematal".

However, the invention is not limited to use of plastics material for the washer mounting.

The spindle may be made of metal, and can be machined from bar stock. It will be noted that the retaining groove 18 can be formed on the bar stock in a machining operation which is continuous with the formation of the external screw threads on the portion 10.

Thus, when a spindle is separated from the bar stock, it can be virtually complete, unless an axial bore 34 is required as referred to above. This is in contrast with production methods for conventional rising spindles, in which it is frequently necessary to machine the face of the spindle adjacent to the washer after separation of the spindle from the stock.

Such machining may be required, for instance, to provide retaining ridges to enable retention of the conventional jumper.

Figure 3 shows an alternative embodiment of the invention in which the washer is snap fitted directly on the spindle. The concept of a directly mounted washer, and one arrangement for mounting the washer directly on the spindle, is described in our prior British Patent Specification 18425/75, Serial No 1 539 881 the full disclosure of which is hereby incorporated in the present specification by reference.

In Figure 3, the spindle is indicated by the numeral 34, and its screwthreads are indicated at 36. Spindle 34 has an extension 38, the lower face of which is flat, with a flange 40 at its free end. The washer 42 snap fits over the flange 40 by means of an integral resilient socket 44, having a flat base, similar to the socket 26 on the mounting element of Figure 1.

The washer 42 and its integral socket 44 are made of a suitable plastics material, which must be arranged to form an adequate seal with the seat of a tap or other fluid flow device in which the spindle is to be used.

A thrust bearing washer 46 is located between the end face of the flange 40 and the corresponding face of the washer 42.

Washer 46 is made of a wear resistant material to reduce the possibility of loosening of the grip of the socket 44 on the flange 40 due to relative rotation of the spindle and the washer during closing and opening of the tap or other fluid flow valve.

A suitable material for the washer 46 is Nylon (RTM).

Since the material of washer 42 is inherently resilient, it is unlikely that the socket 44 will have to be split as shown by the dotted lines in Figure 2, but such splits may be used if desired. Similarly, the washer 42 may have a stub shaft similar to the shaft 32 (Figure 1) and a corresponding bore may be provided in the spindle. Clearly, the washer 46 must then be annular.

Where the socket has splits as shown in Figure 2, it effectively becomes a plurality of radially separable members for gripping the spindle. There may be simply a plurality of such members spaced angularly about the axis of the washer, with substantial discontinuities between them, and this arrangement is considered to lie within the term "socket'' used herein since the plurality of members is as effective as a socket.

It will be appreciated that the illustrated embodiments provide a simple, direct connection between a washer, or washer mounting, and an operating spindle. There is no necessity for additional elements such as Orings to make the snap fit connection. Further, the connection is a positive one, ensured by an interference fit between the connecting parts, rather than a frictional connection. In order to facilitate mounting of a washer mounting such as mounting 16 (Figs 1 and 2) on a spindle such as spindle 12, one or both may have suitable chamfers on their engaging portions. A suitable chamfer is shown on portion 40 of spindle 34 (Fig 3) and a chamfer may be provided alternatively or in addition in socket portion 44 of the washer.

WHAT WE CLAIM IS: 1. A fluid flow control valve including a valve seat and a valve closure member that is movable towards and away from the valve seat by rotation of a spindle, about its axis, connected to the valve closure member, the end face of the spindle nearer to the closure member being flat and the closure member comprising, or being attached to, an element having a resilient socket with a flat base, an end portion of the spindle being a snap-fit within the socket with the flat face of the spindle facing the flat base of the socket, and the spindle being rotatable about its axis relative to the closure member.

2. A valve as claimed in Claim 1 wherein said element comprises an integral sealing surface for forming a seal against the valve seat when the valve is in its closed position.

3. A valve as claimed in Claim 1 wherein said element has attached thereto a separately formed sealing washer for forming a seal against the valve seat when the valve is in its closed position.

4. A valve as claimed in Claim 3 wherein the sealing washer is attaced to said element by a "fir-tree".

5. A valve as claimed in any preceding claim wherein there is a thrust-bearing member or a wear resistant member disposed between said end face of the spindle and the base of the socket.

6. A valve as claimed in any preceding claim wherein the socket comprises a plurality of radially resilient members.

7. A valve as claimed in any preceding claim wherein the socket has one or more inwardly directed projections which engage as a snap-fit an external shoulder on the spindle.

8. A valve as claimed in Claim 7 wherein the or each projection is in the form of a flange.

9. A valve as claimed in Claim 7 or Claim 8 wherein the shoulder is part of a circumferential recess formed in the spindle.

10. A valve as claimed in any preceding claim wherein said element has guide means for guiding axial movement thereof relative to the spindle.

11. A valve as claimed in Claim 10 wherein the guide means comprises a shaft that projects into an axial bore in the spindle.

12. A fluid flow control valve as claimed in claim 1 wherein the closure member is substantially as hereinbefore described with reference to and as illustrated in Figure 1, Figure 2 or Figure 3 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (12)

**WARNING** start of CLMS field may overlap end of DESC **. "socket'' used herein since the plurality of members is as effective as a socket. It will be appreciated that the illustrated embodiments provide a simple, direct connection between a washer, or washer mounting, and an operating spindle. There is no necessity for additional elements such as Orings to make the snap fit connection. Further, the connection is a positive one, ensured by an interference fit between the connecting parts, rather than a frictional connection. In order to facilitate mounting of a washer mounting such as mounting 16 (Figs 1 and 2) on a spindle such as spindle 12, one or both may have suitable chamfers on their engaging portions. A suitable chamfer is shown on portion 40 of spindle 34 (Fig 3) and a chamfer may be provided alternatively or in addition in socket portion 44 of the washer. WHAT WE CLAIM IS:

1. A fluid flow control valve including a valve seat and a valve closure member that is movable towards and away from the valve seat by rotation of a spindle, about its axis, connected to the valve closure member, the end face of the spindle nearer to the closure member being flat and the closure member comprising, or being attached to, an element having a resilient socket with a flat base, an end portion of the spindle being a snap-fit within the socket with the flat face of the spindle facing the flat base of the socket, and the spindle being rotatable about its axis relative to the closure member.

2. A valve as claimed in Claim 1 wherein said element comprises an integral sealing surface for forming a seal against the valve seat when the valve is in its closed position.

3. A valve as claimed in Claim 1 wherein said element has attached thereto a separately formed sealing washer for forming a seal against the valve seat when the valve is in its closed position.

4. A valve as claimed in Claim 3 wherein the sealing washer is attaced to said element by a "fir-tree".

5. A valve as claimed in any preceding claim wherein there is a thrust-bearing member or a wear resistant member disposed between said end face of the spindle and the base of the socket.

6. A valve as claimed in any preceding claim wherein the socket comprises a plurality of radially resilient members.

7. A valve as claimed in any preceding claim wherein the socket has one or more inwardly directed projections which engage as a snap-fit an external shoulder on the spindle.

8. A valve as claimed in Claim 7 wherein the or each projection is in the form of a flange.

9. A valve as claimed in Claim 7 or Claim 8 wherein the shoulder is part of a circumferential recess formed in the spindle.

10. A valve as claimed in any preceding claim wherein said element has guide means for guiding axial movement thereof relative to the spindle.

11. A valve as claimed in Claim 10 wherein the guide means comprises a shaft that projects into an axial bore in the spindle.

12. A fluid flow control valve as claimed in claim 1 wherein the closure member is substantially as hereinbefore described with reference to and as illustrated in Figure 1, Figure 2 or Figure 3 of the accompanying drawings.