GB2032580A - Flow restrictor device - Google Patents

Abstract

In a pillar tap comprising an annular valve 5 which is seated when the tap is closed and is displaced to open the tap, a cylindrical member 9 displaceable with the valve reduces the cross-sectional area of the outlet end of the inlet conduit 2 of the tap in any position of the valve. The member 9 is made of a material unaffected by the liquid flowing through the tap. Such a device is intended to reduce the amount of liquid wastage if a tap is accidentally or deliberately left open. <IMAGE>

Description

SPECIFICATION Improvements in or relating to flow restrictor devices The present invention relates to a device for restricting the flow of liquids, in particular for restricting the flow of water.

The wastage of water is usually only highlighted in drought conditions. However, water wastage can be costly to an industrial user who is charged a water rate in dependance upon the amount of water used. Moreover, such wastage can also waste energy. Thus, for example, if a hot water tap is left running when hot water is not required, energy will be wasted in heating the water.

In theory, it is possible to prevent such water wastage by educating the population to turn taps off when water suppiy is not required. However, there will obviously be occasions upon which a tap is accidently, or even deliberately, left running.

Hitherto, in so-called pillar taps, such water wastage has been regarded as an unavoidable hazard.

In an attempt to overcome this problem, taps have been proposed in which the water-flow through the tap is caused by the user applying pressure to a valve stem. Such pressure removes a valve from its seat, thereby permitting water to flow through the tap. Upon removal of the manually applied pressure, the valve returns to its seat and the water flow is stopped. It will readily be seen that such an arrangement provides the advantage that the tap cannot be accidentally left running. However, such a tap has certain disadvantages. Firstly, such a tap is not suited for industrial use where it is required to run water continuously for a relatively lengthy period of time.

On a smaller scale, such taps find uses in domestic plumbing systems and in the plumbing installations found in some public installations such as public conveniences and motorway service stations. However, in such latter places, the plugs for the washbasins may be vandalized or stolen. Accordingly, the user of a washbasin fitted with such a tap can only maintain the water flow by applying continuous pressure to the valve stem.

This obviously makes personal washing somewhat difficult. It would not, of course, be unduly difficult to provide such a tap with a device which maintained a constant flow of water once the valve had been removed from its seat. However, it will be readily appreciated that the provision of such a device would negate the water saving advantage of such a tap, In view of the virtual impossibility of educating the general public to ensure that taps are completely turned off when not in use, or to provide a water suppiy system which does not waste water and is simple and convenient to use, the present invention seeks to provide a device for limiting the amount of wastage of water rather than to completely eliminate such wastage.

According to the present invention there is provided a liquid flow restrictor device suitable for using in a pillar tap, the device comprising annular valve means displaceable so as, in use, to permit or preclude the passage of liquid from the inlet conduit of the tap to the outlet conduit therof, said valve means having associated therewith an insert member movable with said valve means and being so dimensioned as to, in use, reduce the crosssectional area of the flow path within or adjacent to the inlet conduit, the insert member being made of a material which is substantially unaffected by the liquid employed.

Preferably, the insert member projects, in use, into the inlet conduit.

Advantageously, the insert member is made of a plastics material. Desirably, the insert member is detachably connected to the valve means.

Alternatively, the insert member may be integral with the valve means.

if the insert member is detachably connected to the valve means, the connection between such parts is preferably a screw threaded connection.

The insert member may be of any desired shape but, for commercial reasons, is advantageously provided with a substantially cylindrical external configuration. The exterior surface may be smooth but is preferably provided with a fluting. Such fluting may extend parallel to the longitudinal axis of the insert member but, preferably, subtends a small angle with the longitudinal axis. By so doing, if the valve means and insert member are detachably connected together, the action of the flowing liquid tends to tighten the insert member against the valve means.

The invention will further described, by way of example, with reference to the accompanying informal drawing, the single figure of which shows a longitudinal section through a portion of a conventional pillar tap having a flow restrictor device in accordance with the present invention located therein.

In the drawing, there is shown a conventional pillar tap generally referenced 1. Such a tap includes an inlet conduit 2 and an outlet conduit or spout 3. In use, liquid is located in the inlet conduit 2 and is either prevented or permitted to flow into the outlet conduit or spout 3 in dependence upon the position of a valve arrangement, generally referenced 4, located at the junction of the inlet and outlet conduits 2 and 3. In a conventional pillar tap, the valve 4 comprises a washer 5, usually made of natural or synthetic rubber and locatable on a seat 7, mounted on a valve stem or jumper 6. The upper end of the valve stem 6 is acted upon by a spindle 8 leading to a handwheel, spider or other gripping member (not shown) whilst the valve is being closed and when the washer 5 is located on its seat.As is well known, the tap is operated by rotating the handwheel or other gripping member.

By so doing, the valve stem or jumper 6 is released from the constraining influence of the spindle 8 and the water pressure causes the washer 5 to be lifted off its seat, thereby permitting flow of liquid from the inlet conduit 2 into the outlet conduit 3.

The valve stem or jumper 6 in a conventional pillar tap comprises a spindle having an annular collar intermediate its ends. In use, the washer 5 abuts against the collar.

Such an arrangement is modified to provide a flow restrictor device in accordance with the present invention by providing the spindle with an external screw thread extending from one end thereof to the region of the annular collar. A generally cylindrical insert member 9 having a tapped blind bore formed in one of its end faces is screwed onto the corresponding screw-threaded portion of the valve stem.

From the drawing, which shows the tap in its closed position, it can be seen that the entire length of the insert member 9 is located in the inlet conduit 2 and greatly reduces the effective cross-sectional area thereof. The insert member 9 must have sufficient length to ensure that when the washer 5 is lifted off its seat 7 to the maximum permitted extent, at least a portion of the insert member remains located in the inlet conduit 2. It will, of course, be readily appreciated that when the washer is raised, the insert member is raised therewith.

Since the insert member greatly reduces the effective cross-sectional area of the inlet conduit, it will be readily appreciated that, in use if the tap is accidentally or delibrately left running, the amount of water which passes through the outlet conduit 3, and is therefore wasted, is considerably less than would be the case if the restrictor were not present. It will also be appreciated that the weight of the assembly must be sufficiently low to enable the restrictor device to be raised by the pressure of the liquid.

It will be readily apparant that various minor modifications can be made to the device of the present invention without departing from the scope thereof. Thus, for example, the exterior surface of the insert member could be fluted, the fluting extending in a direction generally parallel to the longitudinal axis of the insert member but partially around the curved surface thereof. By so doing, liquid flowing past the restrictor tends to tighten the insert member against the washer and hence the collar.

The device of the present invention should be freely rotatable to permit any scale carried in the water to be ejected therefrom. In addition, the end face of the insert member opposite to that provided with the tapped blind bore may also be provided with a blind bore. By providing such a further blind bore, the restrictor device of the present invention can act as a dust trap to remove any dust, or other small particles, carried by the liquid passing through the tap.

Claims (13)

1. A flow restrictor device suitable for use in a pillar tap for restricting the flow of liquid, the device comprising substantially annular valve means displaceable between a seated position in which through flow of liquid from the inlet to the outlet of the tap is prevented and a fully open position in which maximum through flow can occur, the valve means carrying an insert member which is displaceable with the valve means, the insert member extending from said valve in a direction towards the inlet of the tap and being so dimensioned as to reduce the cross-sectional area of the flow path for the liquid at the outlet end of the inlet conduit of the tap in any position of the valve means, the insert member being made of a material which is substantially unaffected by the liquid flowing through the tap.

2. A device as claimed in claim 1 wherein the insert member is so dimensioned that the free end face thereof remote from said valve means lies flush with the outlet end face of the inlet conduit of the tap when said valve means is displaced into its fully open position.

3. A device as claimed in claim 1 wherein the insert member is so dimensioned as to project into the inlet conduit irrespective of the location of the valve means.

4. A device as claimed in any preceding claim wherein the insert member is made of a plastic material.

5. A device as claimed in any preceding claim wherein the insert member is integrally formed with the valve means.

6. A device as claimed in any one of ciaims 1 to 4 wherein the insert member is detachably affixed to the valve means.

7. A device as claimed in any preceding claim wherein the insert member has a substantially cylindrical external configuration.

8. A device as claimed in claim 7 wherein the external surface of the insert member is fluted.

9. A device as claimed in claim 8 wherein said fluted portions extend between the end faces of the cylinder and around at least a portion of the curved surface of the cylinder.

10. A device as claimed in claim 9 wherein the insert member is detachably affixed to the valve means by a screw-threaded connection, the fluted portions being so directed that the passage of liquid flowing past the insert member tends to tighten the insert member against the valve means.

11. A device as claimed in any preceding claim wherein said valve means and insert member are freely rotatable about their longitudinal axes when said valve means is displaced from its seated position.

12. A device as claimed in any preceding claim wherein the free end face of the insert member remote from said valve means has a longitudinally extending blind bore formed therein, said blind bore acting, in use, as a trap for dust or other small particles carried by the liquid flowing through the tap.

13. A flow restrictor device constructed and arranged to operate substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.