GB2238849A - Push tap - Google Patents

Abstract

A press operated adaptor comprises an insert body 11 inserted within a tap body 10, said insert body having a central bore within which is slidably and sealingly located an actuator rod 14 including a central fluid flow bore 17 and intersecting diametric bore 18 to enable fluid flow through said actuator rod into a chamber at the lower end of said central bore of said insert body 11. The insert body also includes fluid flow apertures 19 to enable fluid to flow from said central chamber out through the outlet of said tap in the open position of the actuator rod 14. Biassing means, spring 15 is provided to return the actuator rod to its closed position upon release such that O-rings sealingly isolate the diametric bore 18 from the chamber of the insert body to shut off the flow. Delay means comprising a piston 29 and cylinder 22 arrangement may be provided for delaying the return action of the actuator rod 14 to enable the tap to remain on for a predeterminable period following release after actuation. <IMAGE>

Description

PUSH TAP The present invention relates to a tap, or more particularly a water tap, particularly suitable for use in public buildings where it is desired to avoid wastage of water.

At present, a variety of arrangements are known for avoiding excess use and wastage of water, examples of which include flow restrictors incorporated within a tap body or push taps which, when released, automatically close off the water supply. Of the various prior art arrangements, the majority include the need for replacement of an existing tap with a new tap incorporating the water saving features, but in older installations, this may be troublesome, in that replacement of taps can occasionally damage the fixtures to which they are attached. Further, the replacement of a complete tap is relatively expensive, and many of the prior push tap devices have been subject to failure, with consequent loss of use of the tap and subsequent cost of repair and maintenance.

It is the object of the present invention to supply a push tap arrangement for adapting existing taps in a relatively simple and economical manner which also provides E reliable low maintenance installation.

According to the present invention there is provided a press-operated adaptor for taps comprising, an insert body locatable in a tap body in use, said insert body having a central bore, in which is located an actuator rod which,when depressed, opens a fluid flow path for liquid, but which, when released, is biassed to automatically close the fluid flow path.

Preferably, the insert member is sealingly seated within the valve body and is provided with fluid flow apertures to provide a restricted flow of fluid therethrough and out of the tap in which it is located, and further preferably, the actuator rod includes a central bore and an intersecting diametric bore to allow fluid to flow through the actuator rod and then through the fluid flow apertures in the insert body.

In a preferred embodiment of the invention a delay means is provided to slow down the return of the actuator rod to the closed position and may comprise pressure differential means and/or friction means and/or a weaker spring and/or reduced pressure means acting on the actuator rod. The delay means may comprise an extension of said actuator rod sealingly slidable in a sealed air or water containing chamber in which at least the pressure of air in said chamber acts to slow down the return of the rod to the closed position.Preferably the delay means comprises a piston - cylinder arrangement with respectively said piston or cylinder connected to said actuator rod or said cylinder or piston rod to be mounted to be held stationary and with a portion of said cylinder having a water chamber acting to slow down the return of said actuator to the closed position closing the fluid flow path.

The present invention will be described further, by way of example, with reference to the accompanying drawings, in which Fig. 1 is a section through a push tap and a push tap adaptor of the present invention; and Fig. 2 is an enlarged fragmentary section of the tap of Fig. 1 with a modification of the adaptor.

A tap body 10 of conventional design is shown, in which is threadingly inserted an insert member 11, which is sealingly seated on a washer 12, located within the valve body 10, said insert member II having a central bore 13 in which is located an actuator rod 14. The actuator rod 14 is secured to a cap 15 and a spring 16 is positioned between the cap 15 and the insert body 11, so as to bias the actuator rod and the cap 15 upwardly into a "normally closed" position.

In the embodiment shown, the tap is in an open state i.e. fluid is enabled to flow through the tap via a central bore 17 in the actuator rod 14 and out through a diametric bore 1B in the actuator rod 14 and then out through at least one radial bore 19 in the insert body 11. When pressure on the cap 15 is released, a combination of the biassing of the spring 16 and the water pressure acting on the lower surface of the actuator rod 14 causes the actuator rod to be upwardly displaced until the bores 1B are effectively closed by the 0-ring 20 engaging the internal wall of the bore 13 in the insert member 11 and continues to be displaced upwardly until the 0-ring 21 engages against the internal wall of the bore 13 to provide a secure seal.Additional 0-rings are provided above the bore and below the 0-ring 21, to prevent egress of the water around the end or along the shaft of the actuator rod 14.

The insert member and actuator rod 11 and 14 are each preferably made of plastics material, whilst the cover 15 is preferably made of chrome plated brass and may include a cap to cover the retaining screw in the top thereof, which may be suitably colour coded to indicate whether such relates to a hot or cold tap. Although the internal components are of plastics material, the provision of a metal cap ensures that such is relatively vandal-proof, in that the plastics material components are protected within the metal of the tap and cover, whilst the use of plastics material for the internal components renders such reasonably inexpensive to produce and requires little or no maintenance, other than the possible renewal of 0-rings periodically, if such should become excessively worn.

Further, since the flow of water is via a series of bores, i.e. either axially or radially in both the actuator rod and the insert member, the flow rate can be reasonably precisely controlled, according to prevailing local water pressure, by adjusting the size and number of bores provided. Finally, since such can be readily inserted into an existing tap fitting with no modification, the arrangement is simple and cheap to instal.

In the modification illustrated in Fig. 2, means are provided to delay return of the actuator rod 14 and includes a tubular insert 22 having an upper outwardly projecting collar 23 seated on the valve seat (possibly via the intermediary of a sealing washer 12 (not shown in Fig. 2) as in Fig. 1 ) and being clamped in position thereon by the end of insert member 11 threaded at 11'. The upper end of tubular insert 22 is open to bore 17 whilst the side walls have a plurality of apertures 24 (only two shown) communicating the interior of the insert 22 with the pressure and source side 25 of the tap to permit inflow of water.

The lower end of tubular insert 22 is closed apart from a threaded bore 26 in which a threaded shaft of a large headed screw 27 sealingly cooperates and is provided to enable the water in lower tubular insert portion 28 to be adjusted.

A plunger or piston 29 is slidable in the inside bore of insert 22 and is sealed relative thereto by ring 30 or other sealing means. The piston is suspended from the actuator rod 14 by a piston rod 31 which extends with clearance from the walls of bore 17 in rod 14 and is bonded to rod 14 at the upper end of bore 17.

The operation of the tap of Fig. 2 is the same'as that of Fig. 1 except that after the cap 15 has been manually depressed and then released, the reduced water pressure effect of chamber portion 28, pressure of water on the flat upper surface of ring 30 and piston 29 together with the frictional effect of the ring 30 on the walls of tubular insert 22 acts to delay return of the rod 14 and its lower seal into engagement with the sealing face of insert member 11 to close the tap. Figs. I and 2 show the tap in the closed position. The screw 27 enables the device to be adjusted so that as the piston moves upwards a reduced pressure effect thus created slows down the return to make the tap operate more satisfactorily. In practice when depressed, the lower end of rod 14 stops slightly above the collar 23 of insert 22. Also the water chamber (portion 28) may be of greater relative length than illustrated. The chamber 28 will normally contain only water although some air may be present without disadvantage.

It is to be appreciated that the delay means may be effected by many different aspects including the damping effect caused by water slowly seeping or flowing into chamber 28 possibly past ring 30 or through threaded bore 26 which creates an hydraulic suction delay effect.

Claims (8)

1. A press-operated adaptor for taps comprising, an insert body locatable in a tap body, in use, said insert body having a central bore, in which is located an actuator rod, which, when depressed opens a fluid flow path for liquid, but which, when released, is biased to automatically close the fluid flow path.

2. An adaptor as claimed in claim 1 in which said insert body is sealingly seated within the tap body and said fluid flow path comprises fluid flow apertures to provide a restricted flow of fluid therethrough.

3. An adaptor as claimed in claim 2 in which the actuator rod includes a central bore and an intersecting diametric bore to allow fluid to flow through the actuator rod into the central bore of the insert body and then through the fluid flow apertures to enable flow from the tap when in the open position.

4. An adaptor as claimed in any preceding claim in which the actuator rod supports a plurality of sealing O-rings to sealingly locate such within the central bore of the insert body to prevent the egress of fluid and additionally to provide seating and sealing means in the closed position of the actuator rod.

5. An adaptor as claimed in any preceding claim in which delay means -is provided to retard the return of the actuator rod to the closed position following actuation.

6. An adaptor as claimed in claim 6 in which the delay means comprises a piston and cylinder arrangement, said piston forming an extension of the actuator rod and being sealingly slidable in a cylindrical chamber, which chamber is formed as an extension of the insert body, and in which at least the pressure of air or water in said chamber acts to slow the return of the actuator rod to the closed position following actuation.

7. A press operated adaptor for taps substantially as hereinbefore described with reference to the accompanying drawings.

8. A push tap including an adaptor as claimed in any preceding claim.