GB2048436A - Fluid flow control valve - Google Patents

Abstract

A radiator valve, is provided with a drainage valve which comprises a body portion 11 which screw-threadedly engages an axially bored nozzle 15. The body portion 11 has a valve seat 13 and the inner end of the nozzle 15 has a valve closure 18 co-operable with the seat 13. Normally, the drainage valve is closed with the closure 18 sealing engaging the seat 13 but may be opened by rotating the nozzle 15 relative to the body portion 11 whereupon fluid can drain from the nozzle via the main control valve body 1, the seat 13 and the axial bore 9 in the nozzle 15. The body portion 11 is preferably integral with the main valve body 1. <IMAGE>

Description

SPECIFICATION Fluid flow control valves This invention relates to fluid flow control valves, particularly but not exclusively to valves for radiators of wet central heating systems.

According to the present invention there is provided a fluid flow control valve comprising a main hollow body having an inlet and outlet connectable in a fluid flow path and housing a main valve seat and a main valve closure movable into and out of sealing engagement with said valve seat for controlling the flow of fluid between the inlet and outlet, characterised in that the main body is provided with a drainage valve comprising an auxiliary hollow body housing an auxiliary valve seat defining an auxiliary outlet in communication with- the interior of the main hollow body, the auxiliary body engaging, and housing an end portion of, an elongate axially bored nozzle having at the end thereof within the auxiliary body an auxiliary valve closure, said nozzle being axially movable between a first position in which the auxiliary valve closure seals against the auxiliary valve seat thereby closing the auxiliary outlet and second position in which the auxiliary outlet is open and communicates the interior of the main hollow body with the axial bore of the nozzle whereby, when the nozzle is in said second position, fluid in at least a part of the flow path can drain from the nozzle via the main hollow body, the auxiliary outlet, the auxiliary hollow body and the axial bore in the nozzle.

In a preferred embodiment, the auxiliary body is integral with the main body and both may be simultaneously formed by, for example, a hot stamping process.

Also in a preferred embodiment, the axial bore of the elongate nozzle extends from the outer end thereof but terminates short of the end having the auxiliary valve closure, there being one or more radial bores in the nozzle which communicate the axial bore with the interior of the main body, via the auxiliary hollow body and the auxiliary outlet, when the drainage valve is in its open position.

Preferably, the nozzle is screw-threadedly engaged in the auxiliary body and is movable between said first and second positions by rotating it relative to the auxiliary body.

A fluid flow control valve of the invention may advantageously be used in conjunction with a wet central heating radiator for which it affords a simple means of draining such a radiator should it be necessary to do so, for example if the radiator needs to be removed for redecoration purposes. It is to be understood, however, that a valve of the invention may be used in a variety of alternative contexts, for example as a stopcock in a water or other fluid pipeline from which, from time to time, it may be necessary to drain the water or other fluid.

A fluid flow control valve of the invention will now be described by way of example only, with reference to the accompanying drawing which is a side elevation partly in section of a conventional radiator valve incorporating a drainage valve.

Referring to the drawing, the radiator valve comprises a main hollow body 1 having a pair of mutually perpendicular, externally screwthreaded, bosses 2 and 3. The bosses 2 and 3 have respective screw-threaded nuts 4 and 5 associated with them and the nut 4 retains an olive 6 in boss 2 whereby a copper feed or return pipe may be connected to the valve in a well known manner, i.e. as a compression fit. The nut 5 also connects an adaptor piece 7 to the valve body 1, also in a well known manner, the end of the piece 7 remote from the body 1 being externally screw-threaded for connection to a central heating radiator.

The main body 1 houses a valve seat 8 and a valve closure member 9, the valve closure being manually operable by a spindle 10 the upper end of which is provided with a handle (not shown). Alternatively, the valve could be of the thermostatically operated type. The aforementioned features are conventional in the art and need not be described in more detail in this specification.

Integral with the main body 1 is a hollow cylindrical body 11 forming part of a drainage valve. The interior of the body 11 communicates with the interior of body 1 through a passageway 1 2 of circular cross-section. The internal surface of the body 11 immediately adjacent to the passageway 1 2 constitutes a drainage valve seat 1 3. The interior wall of part of the length of the body 11 is formed with screw-threads, as shown at 14, and engages an externally screw-threaded, elongate member 15, the innermost end portion 1 6 of which is of reduced external diameter so leaving an annular space 1 7 between the portion 1 6 and the internal wall of body 11.

The end face of the portion 1 6 is tapered and forms a closure 1 8 co-operable with the seat 1 3. The member 1 5 has an axial bore 1 9 extending from its outermost end which bore terminates just short of the closure 1 8 and communicates with the annular space 1 7 via a pair of radial bores 20 in the member 1 5.

The member 1 5 is formed adjacent to the screw-threads thereon with a pair of spaced annular flanges 21, 22 which retain between them a sealing O-ring 23.

In use, normally the valve closure 1 8 engages the seat 13, ie the drainage valve is closed. However, if necessary, the radiator may be very simply drained without, for example, the need to drain other parts of the central heating system, by closing the main radiator valve and opening the drainage valve by rotating the member 1 5 so as the with draw the closure 18 from its seat 1 3. The drawing shows the two valves in these positions. Water can then drain from the radiator along the path indicated by arrows, the water finally issuing from the outermost end of the member 1 5. Needless to say, it may be necessary to close the other of the usual two main radiator valves.If desired a drain tube amy be secured to the outermost end portion of the member 1 5 and this may be facilitated by providing the external surface of that portion with a "firtree" profile as shown at 24.

The radiator valve shown in the drawing is so designed that it may be manufactured at a cost that is very little more than the cost of a similarly sized valve not having drainage facilities. For example, the integral bodies 1 and 11 may be hot stamped in a single stage and thereafter machined and the member 1 5 may be machined from rod. As will be appreciated, the valve may be made of any suitable material(s). For example, the bodies 1 and 11 and the member 1 5 may be of brass.

Whilst the axis of body 11 is shown extending perpendicularly to the axis of body 1, it may be inclined, preferably downwards, thereto.

Claims (6)

1. A fluid flow control valve comprising a main hollow body having an inlet and outlet connectable in a fluid flow path and housing a main valve seat and a main valve closure movable into and out of sealing engagement with said valve seat for controlling the flow of fluid between the inlet and outlet, character ised in that the main body is provided with a drainage valve comprising an auxiliary hollow body housing an auxiliary valve seat defining an auxiliary outlet in communication with the interior of the main hollow body, the auxiliary body engaging, and housing an end portion of, an elongate axially bored nozzle having at the end thereof within the auxiliary body an auxiliary valve closure, said nozzle being axially movable between a first position in which the auxiliary valve closure seals against the auxiliary valve seat thereby closing the auxil iary outlet and a second position in which the auxiliary outlet is open and communicates the interior of the main hollow body with the axial bore of the nozzle whereby, when the nozzle is in said second position, fluid in at least a part of the flow path can drain from the nozzle via the main hollow body, the auxiliary outlet, the auxiliary hollow body and the axial bore in the nozzle.

2. A valve according to Claim 1 wherein the auxiliary hollow body is integral with the main hollow body.

3. A valve according to Claim 1 or Claim 2 wherein the axial bore of the elongate nozzle extends from the outer end thereof and terminates short of the end thereof having the auxiliary closure, there being one or more radial bores in the nozzle which communicate the axial bore with the interior of the main hollow body via the auxiliary hollow body and auxiliary outlet when said nozzle is in its second position.

4. A valve according to any one of Claims 1 to 3 wherein the nozzle is screw-threadedly engaged in the auxiliary hollow body and is axially movable between said first and second positions by rotating the nozzle relative to the auxiliary body.

5. A valve according to any one of Claims 1 to 4 for controlling the flow of water into or out of a wet central heating radiator wherein said inlet or outlet is adapted to be connected to such a radiator and wherein the arrangement is such that, at least when the main valve closure sealingly engages the main valve seat, water can drain from the radiator out of the nozzle when the latter is in its second position.

6. A wet central heating radiator control valve substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.