GB2033550A

GB2033550A - Drain cocks

Info

Publication number: GB2033550A
Application number: GB7935121A
Authority: GB
Original assignee: B & C Water Fittings Ltd
Current assignee: B & C Water Fittings Ltd
Priority date: 1978-10-24
Filing date: 1979-10-10
Publication date: 1980-05-21

Abstract

A drain cock comprises a body 10 having an internal drain passage 14 leading to an outlet 15 of the body; and a valve member 20 movable to close the passage 14 by an actuating member 30 movable in the outlet 15, wherein the valve actuating member has an internal way 33, 42 which opens at one end into the outlet and leads to an opening 53 outside the body 10, so that when the passage 14 is not closed by the valve member liquid can flow from the passage 14 to the opening 53 via the outlet and the internal way 33, 42. The valve actuating member may have a fixed extension 34 or a rotatable extension to accept a hose. <IMAGE>

Description

SPECIFICATION Drain cock This invention concerns drain cocks, for example for radiators of central heating systems, to allow a drain passage to be opened.

One well known type of drain cock of simple form comprises a drain passage having a removable screw-in plug to close the passage. This type of cock is compact, but it does not enable a drain hose to be fitted prior to removal of the plug.

Another well known type of drain cock comprises a drain passage, having an inlet and an outlet, and a valve member which normally blocks the passage between the outlet and the inlet. Although a drain hose can be fitted to the outlet prior to actuation of the valve member to open the passage, this type of drain cock needs to be fitted in an otherwise unobstructed location to provide access to the valve member and the outlet.

An object of the invention is to provide an improved drain cock which can be constructed so as to be compact, to be easy to actuate, and to accept a drain hose prior to actuation.

According to the present invention there is provided a drain cock having a body provided with an internal drain passage; wherein a valve member is supported in the drain passage on a valve actuating member so as to be movable about an axis relative to the valve actuating member; wherein the valve actuating member is actuable manually to move the valve member bodily along said axis to engage a valve seat in the body around a closable portion of the passage, which closable portion is disposed between an inlet and an outlet of the drain passage; wherein the valve actuating member extends into said outlet from outside the body, and has an internal way extending from said outlet to an opening outside said body, so that when said valve member is disengaged from said valve seat fluid can flow from said inlet to said opening via said closable portion, said outlet and said internal way.

The outlet is preferably internally threaded, and the valve actuating member preferably has a main portion which is externally threaded to engage the internal thread of the outlet, so that the valve actuating member is actuable by being rotated relative to the body.

Sealing means is preferably provided in the outlet to prevent or hinder fluid escaping via any clearance between said internal and external threads.

Said opening may be provided at a free end of an extension provided on the valve actuating member.

The extension is preferably adapted to have a drain hose fitted thereto, and may be rotatable about said axis relative to the rest of the valve actuating member.

The valve member is preferably of composite construction, e.g. comprising a washer and a washer plate, and is preferably captively retained by the valve actuating member.

The body may be constructed as a T-peice, for connectinn into oioework, in which the passage forms one limb of the T-piece; or may be constructed in any appropriate manner as a fitting for insertion or incorporation into a radiator, boiler, hot water tank or other fluid containing vessel or apparatus.

The invention will be described further, by way of example, with reference to the accompanying drawings, wherein: Figure 1 is an exploded sectional diagram showing the component parts of a drain cock of the invention; Figure 2 shows the drain cock in side elevation; and Figure 3 shows a modified form of valve actuating member for use in the drain cock.

The drain cock comprises a body 10, a valve member 20 and a valve actuating member 30.

The body 10 is in the form of a casttpiece machined to provide a main duct 11, a drain passage and a valve seat 12 disposed in a closable portion 13 of the passage. The passage includes an inlet 14, which extends from the duct 11 to the portion 13, and an outlet 15. The outlet 15 has an internal thread 16 as shown in Figure 1.

The valve member 20 comprises a washer 22 and a jumper. The jumper comprises a washer plate 21 integral with an axial jumper shank 23 which is stepped to produce a waist 24 around the root of the shank 23. The washer 22 is retained on the washer plate by a head on a further shank co-axial with and remote from the jumper shank 23.

The valve actuating member 30 has a head portion 31 which projects axially from one end of a main portion 32. The main portion 32 has an axial bore 33 which extends through an extension 34. The extension 34 projects axially from the other end 35 of the main portion 32. The other end 35 is externally shaped to provide flats 36 (Figure 2) for engagement by a spanner. The extension 34 is externally shaped to accept a drain hose.

The head portion 31 bridges the bore 33, and is provided with an axial socket 40 which is partially defined by a thin walled part cylindrical nose 41 of the head portion. The head portion 31 is provided with one or more non-axial bores 42 (two are shown in Figure 1), so as to connect with the bore 33, said bores 33 and 42 together serving an internal way through the valve actuating member 30.

During assembly of the drain cock the jumper shank 23 is inserted into the socket 40, and the nose 41 is constructed slightly to enter the waist 24 to hold the jumper captive on the head portion 31, whilst permitting relative axial rotation therebetween.

Sealing means, in the form of a plastics ring 50 is provided in an annular slot which interrupts an external thread 51 on the main portion 32.

During assembly the valve member and valve actuating member are inserted into the outlet to engage the threads 16 and 51, and said members are moved axially along a common axis 52, by rotating the valve actuating member 30, until the washer 22 firmly abuts the seat 12 to block the drain passage.

In use, the cock can be opened by a reverse rotation of the valve actuating member 30 until the washer 22 leaves the seat to allow fluid to flow from the inlet 14 through the portion 13, the outlet 15, the bores 42 and the bore 33 to an opening 53 at the end of the extension 34, the ring 50 serving to prevent leakage between said thread.

A detachable cover 54 of cup form may be clipped or pressed onto the extension to conceal and protect the outlet and valve actuating member, as shown in Figure 2.

Referring to Figure 3, the modified valve actuating member 30A is similar to the valve actuating member 30 and includes the head and main portions 31 and 32, the bore 33 and the flats 36. The valve actuating member 30A differs from the valve actuating member 30 in that is has: (a) an end 35A which is grooved to provide a first annular channel 60 and a second annular channel 61: (b) an extension 34A having a hollow interior 62 which, together with the bores 33 and 42, serves as a way connecting the outlet 15 with the opening 53A at one end of the extension 34A; having an internal flange 63 at the end remote from the opening 53A, which flange 63 engages in the channel 60 to locate the extension rotatably on and co-axial with the end 35A; and having an external surface shaped to accept a hose: (c) an O-ring 64 located in the channel 61 to serve as a seal between the end 35A and the extension 34A; and (d) an uninterrupted external thread 51A which is arranged to engage sealing means in the form of an O-ring 50A located at the end of the outlet 15 as indicated in broken lines in Figure 1.

This modified valve actuating member has the advantage that the main portion 32 can be rotated with a hose connected to the extension 34A without requiring the hose to be rotated also.

The invention is not confined to the precise details of the foregoing examples, and many variations are possible within the scope of the invention as defined by the appended claims. For example, a knob may be secured to or provided on the valve actuating member to obviate the need to use a spanner for opening and closing the cock. The valve actuating member may have provided thereon a peripheral extension or collar having a cylindrical portion which surrounds the part of the body around the outlet; which part may be externally threaded to engage an internal thread in the cylindrical portion, to obviate the threads 16 and 51, the ring 50 being optionally retained to provide the sealing means between the confronting cylindrical surfaces of the outlet and main portion or replaced by a ring interrupting the external thread on said part of the body. The sealing means could be in the form of a layer of elastomeric plastics, grease or other suitable material disposed between the valve actuating member and the body.

Claims

1. A drain cock having a body provided with an internal drain passage; wherein a valve member is supported in the drain passage on a valve actuating member so as to be movable about an axis relative LU tilC valve dULUdLisly Ill#llI;#I# YV;lt#lc#;ll lid valVe: actuating member is actuable manually to move the valve member bodily along said axis to engage a valve seat in the body around a closable portion of the passage, which closable portion is disposed between an inlet and an outlet of the drain passage; wherein the valve actuating member extends into said outlet from outside the body, and has an internal way extending from said outlet to an opening outside said body, so that when said valve member is disengaged from said valve seat fluid can flow from said inlet to said opening via said closable portion, said outlet and said internal way.

2. A drain cock as claimed in claim 1, wherein the outlet is internally threaded, and the valve actuating member preferably has a main portion which is externally threaded to engage the internal thread of the outlet, so that the valve actuating member is actuable by being rotated relative to the body.

3. A drain cock as claimed in claim 1 or 2, wherein sealing means is provided in the outlet to prevent or hinder fluid escaping via any clearance between said internal and external threads.

4. A drain cock as claimed in claim 3, wherein the sealing means comprises a resilient O-ring.

5. A drain cock as claimed in claim 1,2,3 or 4, wherein the opening is provided at a free end of an extension provided on the valve actuating member.

6. A drain cock as claimed in claim 5, wherein the extension is adapted to have fitted to it a drain hose.

7. A drain cock as claimed in claim 4 or 5, as appended to claim 2, wherein said extension is rotatable, about said axis, relative to the main portion of the valve actuating member.

8. A drain cock as claimed in any preceding claim, wherein the valve member comprises a washer mounted on a washer plate.

9. A drain cock as claimed in any preceding claim, wherein the valve member is captively retained by the valve actuating member.

10. A drain cock substantially as hereinbefore described with reference to Figures 1 and 2, or Figures 1 and 2 as modified by Figure 3 of the accompanying drawings.