GB2291152A

GB2291152A - Radiator valve tailpiece

Info

Publication number: GB2291152A
Application number: GB9513526A
Authority: GB
Inventors: Melvyn Holdsworth
Original assignee: Pegler Ltd
Current assignee: Pegler Ltd
Priority date: 1994-07-04
Filing date: 1995-07-03
Publication date: 1996-01-17
Also published as: GB9413415D0; GB9513526D0

Abstract

A tailpiece 50 for connecting a radiator valve body 80 to a radiator 60 comprises an externally threaded tail portion 52 for connection to the radiator 60 and a union 70 for connection to the radiator valve body 80. The union 70 has a sealing surface 68 for sealing engagement with a co-operative surface 84 of the valve body 80 and a union nut 64 surrounding the tailpiece for threaded engagement with a portion of the valve body 80. Tightening the nut 64 brings the sealing surfaces 68, 84 into close contact with one another. Retention means such as a clip 76 or a threaded sleeve (figure 3) is applied to the tailpiece 50 to retain the union nut 64 thereon. The tailpiece 50 also has a drain passage 56. <IMAGE>

Description

RADIATOR VALVE TAILPIECE The present invention relates to radiator valve tailpieces.

In central heating systems, water is heated by a boiler and pumped through connecting pipes to a plurality of radiators, each being effective to transfer heat from the water to its surroundings. Typically, each radiator has a water inlet and a water outlet, each of which is provided with a valve by which water in the pipes may be isolated from the radiator.

It is normal for each valve to be connected to the radiator by a tailpiece. With reference to Figures 1 and 2, a tailpiece typically comprises a tail 10 of tubular section, a sealing surface 12, a collar 14 or similar, to retain a union nut 16. The tail 10 is threaded for connection to the radiator, while the union nut 16 serves to connect the tailpiece to a radiator valve body in a watertight manner. Two arrangements of connection are well known. As shown in Figure 1, the connection may comprise a ball and collar union. Alternatively, it may comprise a compression joint as shown in Figure 2. Both these types of union are in regular use.

From time to time, a radiator must be removed from the system for maintenance or other operations. It is often convenient to do this without draining the entire heating system. In order to do this, the radiator must first be isolated from its connecting pipes: this is easily achieved by closure of its inlet and outlet valves. Then, the water contained within the radiator must be drained safely before the valves can be disconnected from the tailpiece. This second procedure has traditionally posed problems, being carried out simply by slackening the connection between the valve body and the tailpiece, and making whatever arrangements are possible to catch water which then emerges from the tailpiece. A solution to this problem, as disclosed in UK Patent Application No. 2149886, provides a closable drain passage on the tailpiece.However, the presence of the drain passage means that a conventional ball and collar union cannot be provided since the union nut cannot pass over the drain passage into position behind the collar on assembly of the tailpiece.

An aim of the present invention is to provide a tailpiece having a union with a ball and collar type construction and which may be provided with a drain passage.

According to the invention, there is provided a tailpiece for connecting a radiator valve body to a radiator comprising an externally threaded tail portion for connection to a radiator and a union for connection to a radiator valve body, the union comprising a sealing surface for sealing engagement with a co-operative surface of the valve body, a union nut surrounding the tailpiece for threaded engagement with a portion of the valve body and arranged, on tightening, to bring the sealing surfaces into close contact with one another, and retention means applicable to the tailpiece to retain the union nut thereon.

The retention means may. be applied to the tailpiece after the union nut has been placed on the tail so avoiding the need to pass the union nut onto the tailpiece from the tail end. Where the tailpiece includes a drain passage, this significantly facilitates assembly of the tailpiece.

The retention means may comprise a tubular extension of the tailpiece attached thereto by, for example, brazing. In such embodiments, the sealing surface is typically formed on the extension.

More preferably, the retention means comprises clip means applied to the tailpiece and retained axially thereon by an abutment. The abutment typically comprises an external groove on the tailpiece and the clip means may comprise a C-shaped clip, a wire circlip, or any other suitable similar device.

Embodiments of the invention will now be described in detail, by way of example, with reference to the accompanying drawings in which: Figure 1 and Figure 2 are examples of conventional tailpieces, and have already been described; Figure 3 is a part-sectional side view of a tailpiece being a first embodiment of the present invention; and Figures 4 and 5 are part-sectional side views of a radiator valve assembly mounted on a radiator each incorporating a tailpiece being, respectively, second and third embodiments of the invention.

With reference first to Figure 3, a radiator tailpiece constitutes a first embodiment of the present invention.

The tailpiece comprises a tubular body 20, a first end portion of which constitutes a tail 22 which is externally taper threaded in a manner well known to those skilled in the art, for connection to a radiator.

Adjacent the tail 22, the body 20 is formed externally with a plurality of flats 24 to facilitate tightening of the tailpiece on connection with a radiator.

Intermediate the ends of the body 20, there is provided a closable drain passage 26, by means of which a radiator to which the tailpiece is attached may be conveniently drained of water. The function and construction of a suitable drain passage is fully described in UK Patent Application No. GB-A-2149886 of the present applicant.

An end portion 30 of the body 20 remote from the tail 22 is externally threaded. Onto this end portion 30 there is mounted a ferrule 32 which constitutes an extension of the tailpiece. In an alternative embodiment, the said end portion is internally threaded to receive an externally threaded portion of the ferrule.

The ferrule 32 is secured on the body 20 by threaded engagement with the end portion 30 and, optionally sealed as by brazing or adhesive as shown at 34. The ferrule 32 has an external surface formed, in a first portion, with a ball sealing surface 36 for sealing with a complimentary surface in a radiator valve body. Remote from the sealing surface 36, the ferrule 34 has an external cylindrical portion 38 which is bounded, at its extremity nearest the sealing surface 36, by a radially projecting integral collar 40.

The tailpiece further comprises a union nut 44 mounted on the ferrule 20. The union nut 44 has a cylindrical portion 46 which is internally threaded for threaded engagement with an externally threaded spigot of a valve body. At an axial end portion of the union nut 44, an annular flange 48 projects radially inwardly of the cylindrical portion 46.

The tailpiece is assembled by first placing the union nut 44 over the end portion of the tailpiece remote from the tail 22. The union nut 44 is arranged with its flange 48 close to the drain passage 26, its threaded portion 46 extending therefrom. The ferrule 32 is then assembled onto the body as described. The ferrule 32 and union nut 44 are mutually dimensioned such that the flange 48 of the union nut 44 closely surrounds the cylindrical surface 38 of the ferrule 32, and such that the flange 48 is of a diameter less than the collar 40, interaction of the collar 40 and flange 48 thus preventing removal of the union nut 44 from the body 20 while the ferrule 32 is in position.Further, on tightening of the union nut 44 onto a spigot of a radiator valve body, the flange 48 and collar 40 co-act as to urge the sealing surface 36 into contact with a cooperative surface of the valve body. The union nut 44 and the ferrule 32 thus constitute a ball and collar union of the tailpiece.

With reference now to Figure 4, a tailpiece being a second embodiment of the invention, comprises a body 50 having a tail 52, flats 54, and a drain passage 56, substantially as described with reference to Figure 3.

As shown in Figure 4, the tail 52 is in threaded engagement with a complimentarily threaded hole 58 in a radiator 60.

Remote from the tail 52, the tailpiece further comprises a union nut 64, also substantially as described with reference to Figure 3.

An end portion 66 of the body 50 remote from the tail 52 is formed with increased external diameter. This end portion 66 has an outer surface which has a portion remote from the tail 52 which is formed as a sealing surface 68 and a further portion 70 extending from the sealing surface 68 towards the tail 52 being generally cylindrical in shape. In this cylindrical portion 70, there is formed a circumferential groove 72 of rectangular section.

A clip 76 being generally C-shaped and of square section metal (such as steel or brass) is provided, and located within the groove 72. The clip 76 has an internal diameter closely corresponding to the external diameter of the groove 72, and has an external diameter closely corresponding to the core diameter threaded portion of the union nut 64.

To assemble the tailpiece, the union nut 64 is first passed over the end portion 66 of the body 50 with its flange towards the drain passage 56. The clip 76 is then applied to the groove 72, thus preventing removal of the union nut 64 from the body 50. The clip 76 is dimensioned such that it is a close fit within the threaded portion of the union nut 64, and of sufficient depth within the groove 72 to prevent its coming out of the groove under load. The clip 76, the end portion 66 of the body 50 and the union nut 64 thus constitute a ball and collar union of the tailpiece.

As will be seen from Figure 4, the tailpiece may be attached to a valve body 80 by threaded attachment of the union nut 64 to a threaded spigot 82 of the valve body 80. An end surface 84 of the spigot 82 is shaped to be complimentary with the sealing surface 68 of the tailpiece. On tightening of the union nut 64 onto the spigot 82, the body 50 is urged by the flange of the union nut 64, acting through the clip 76 towards the spigot 82, the sealing surfaces 68,84 of the body 50 and the spigot 82 being urged into contact with one another, so as to form a water-tight seal.

With reference to Figure 5, there is shown a third embodiment of the invention, being similar in construction to the second embodiment described above and having corresponding features indicated by corresponding reference numerals. In this embodiment, the end portion 66 of the body 50 is provided with a groove 90 of rounded section, in which is located a circlip 92 of round section, resilient wire. The circlip 92 serves to retain in place the union nut substantially as does the clip 76 of the second embodiment.

Claims

CLAIMS:

1. A tailpiece for connecting a radiator valve body to a radiator comprising an externally threaded tail portion for connection to a radiator and a union for connection to a radiator valve body, the union comprising a sealing surface for sealing engagement with a co-operative surface of the valve body, a union nut surrounding the tailpiece for threaded engagement with a portion of the valve body and arranged, on tightening, to bring the sealing surfaces into close contact with one another, and retention means applicable to the tailpiece to retain the union nut thereon.

2. A tailpiece for connecting a radiator valve body to a radiator according to claim 1 in which the retention means may be applied to the tailpiece after the union nut has been placed on the tail.

3. A tailpiece for connecting a radiator valve body to a radiator according to claim 1 or claim 2 in which the retention means comprises a tubular extension of the tailpiece attached thereto.

4. A tailpiece for connecting a radiator valve body to a radiator according to claim 3 in which the sealing surface is formed on the extension.

5. A tailpiece for connecting a radiator valve body to a radiator according to claim 1 or claim 2 in which the retention means comprises clip means applied to the tailpiece and retained axially thereon by an abutment.

6. A tailpiece for connecting a radiator valve body to a radiator according to claim 5 in which the abutment comprises an external groove on the tailpiece.

7. A tailpiece for connecting a radiator valve body to a radiator according to claim 1 in which the clip means comprises a C-shaped clip, a wire circlip, or any other suitable similar device.

8. A tailpiece for connecting a radiator valve body to a radiator according to any preceding claim which incorporates a drain passage.

9. A tailpiece for connecting a radiator valve body to a radiator substantially as herein described with reference to any one of Figures 1, 2 or 3 of the accompanying drawings.

10. A radiator valve incorporating a tailpiece according to any preceding claim.