The use of a bi-directional flow TRV allows the valve to operate normally regardless of the direction of flow of water through the valve, and allows the valve to be fitted to either end of a central heating radiator in either the horizontal or vertical position without loss of performance.

With traditional TRV designs the flow of water must follow the direction of the arrow provided on the valve body otherwise the valve can become prone to hammering and chattering. If this happens the only solution is to remove the valve and change its position to follow the flow direction arrow. This can result in high costs for installers who have to return to sites to rectify the problem.

The use of a bi-directional flow TRV design means that the valve is not flow directionally sensitive and should result in significantly reduced call back charges for installers. This is particularly relevant in replacement or upgrade situations where the inlet and outlet pipes are not always easily identifiable.

Previous attempts at providing a bi-directional TRV have been only partially effective in eliminating vibration in the valve such that some hammering and chattering still occurs.

It is an object of the present invention to provide an improved form of bi- directional flow TRV.

According to the present invention there is provided a thermostatic radiator valve comprising a valve body having a valve seat disposed between input and output connections to said valve, a valve closure member adjustably disposed adjacent said valve seat for controlling flow through said valve, a valve spindle spring mounted in said valve body on one end of which said valve closure member is disposed, a thermostatic radiator valve head mounted on said

valve body and being operable on the other end of said valve spindle for controlling the operation of said valve, said valve closure member comprising a bush, typically of brass, having a resilient member for contacting said valve seat rigidly secured to it, said bush being disposed on a reduced diameter end portion of said spindle and being rigidly attached to said spindle.

In a preferred valve in accordance with the present invention, said resilient member is bonded to said bush and said one end of said spindle is mechanically deformed e. g. by staking to retain said bush on said reduced diameter portion thereof.

An exemplary embodiment of the invention will now be described, reference being made to the accompanying single figure drawing which is a cross-sectional view of a thermostatic radiator valve, apart from the valve head, in accordance with the present invention.

The valve shown in the drawing is designed for use with a conventional thermostatic radiator valve head which, for convenience, is not shown in the drawing.

The valve shown comprises a valve body 1 of substantially conventional form having a first input/output connection 2 and a second input/output connection 3. A passage 4 is provided in the valve body 1 between the input and output connections 2 and 3, the upper perimeter of the passage 4 constituting a valve seat 5.

Disposed above the valve seat 5 is a valve closure member 6 consisting of an inner bush 7, typically of brass, to the periphery of which is bonded a disc- shaped resilient e. g. rubber member 8, the lower peripheral surface 9 of which is contoured for making sealing contact with the valve seat 5.

The brass bush 7 of the closure member 6 is mounted on a reduced diameter end portion 10 of an operating spindle 11 the end of which is staked in order to securely fix the brass bush 7 and thus the closure member 6 on the spindle 11.

The operating spindle 11 is spring mounted in an insert body 12, typically

made of brass, which is screwed into an upper aperture 13 in the valve body 1.

The spindle 11 is retained in the insert body 12 by means of a retainer member 14 which is screwed into an upper aperture 15 in the insert body 12 and through the centre of which an upper end 16 of the operating spindle 11 extends.

An"O"ring seal 17 is provided between the spindle 11 and the retainer member 14 to prevent water leakage around the periphery of the spindle 11.

The operating spindle 11 is spring mounted in the insert body 12 by means of a spring 18 contained within the insert body 12 and which acts on a plastic spring retainer 19 which is moulded onto a central shouldered portion 20 of the spindle 11, the action of the spring 18 being to urge the operating spindle 11 in an upwards direction as viewed in the drawing, so that the closure member 6 is maintained in a valve open position relative to the valve seat 5.

The upper end 16 of the operating spindle 11 is acted upon in the usual way by a thermostatic radiator valve head (not shown) which in practice would be screwed onto the threaded upper part 21 of the valve body 1. The action of the valve head is to thermostatically control the position of the closure member 6 relative to the valve seat 5, to control flow between the input/output connections 2 and 3.

By ensuring that the disc-shaped resilient member 8 is securely bonded to the brass bush 7 and that the brass bush 7 is securely mechanically fixed to the operating spindle 11, any vibrational effects in the valve are greatly reduced.

This is further enhanced by ensuring that the spring retainer 19 is also firmly secured on the operating spindle 11.

The thermostatic radiator valve described with reference to the drawing therefore lends itself to connection in either end of a radiator installation with the consequent installation advantages.

The bi-directional flow TRV which has been described has been given by way of example only and although a so-called"angle"valve has been described, the invention is equally applicable to so-called"straight"and"inverted angle" valves, and to such valves of different sizes, e. g. l5mm, 25mm, etc.