GB2213330A

GB2213330A - Electrical continuity in plastics-bodied fittings

Info

Publication number: GB2213330A
Application number: GB8828186A
Authority: GB
Inventors: Gerald Alfred John Springer
Original assignee: DEREVE
Current assignee: DEREVE
Priority date: 1987-12-02
Filing date: 1988-12-02
Publication date: 1989-08-09
Anticipated expiration: 2008-12-02
Also published as: GB2213330B; GB8828186D0; GB8728209D0

Abstract

A plastics valve housing of electrically non-conductive material is provided with inlet and outlet couplings (15) made from an electrically conductive material. Each coupling (15) is provided with a retaining strap (20) which straps are secured together by bolts (24) also made from an electrically conductive material. The electrically conductive couplings (15) may be made from a metallic material which provides strength and, through the retaining means, also provides electrical continuity between the inlet and the outlet. <IMAGE>

Description

Title: "Fitting" Description of Invention The present invention relates to a fitting to which at least one element may be coupled.

The invention is primarily, but not exclusively, concerned with the connection of pipes for fluid flow to each other or to valves or other fittings.

Valves and such fittings for controlling fluid flow such as water, gas and other fluids, are commonly made from metallic material such as brass, copper or iron. There is however an increase in the number of fittings made from plastics material, which fittings can show appreciable cost saving in manufacture.

There are however two problems that occur with plastics fittings: (a) the strength of the fitting is not normally as great as that of a metal fitting: (b) plastics material is electrically non-conductive and it is often required for plumbing or other pipework installations to constitute an electrically conductive path.

It is an object of the present invention to provide a new or improved fitting that overcomes or minimises the problems mentioned above.

According to one aspect of the present invention we provide a fitting made at least in part of an electrically non-conductive material, said fitting being provided with a coupling, at least part of which is made from electrically conductive material.

Preferably, said coupling is secured to said fitting by a retaining member made from electrically conductive material.

Preferably, the fitting is provided with a pair of couplings and wherein said at least electrically conductive part of each of said couplings are connected to each other through the or each electrically conductive retaining member.

Preferably said pair of couplings are connected to each other in a manner to secure said couplings to said fitting.

The fitting may be provided in part with an electrically conductive material and the or each fitting is connected at least electrically to said electrically conductive material.

In a case where the fitting is provided with electrically conductive material, the fitting may be made from a plastics material and said part of electrically conductive material may be subsequently secured thereto or alternatively may be moulded in position during the moulding of the fitting.

Said coupling is preferably capable of connection to a pipe and said coupling may comprise one part of a compression joint, a solder joint or threaded joint or any other type of joint used in fluid flow pipework.

The fitting may comprise a fluid flow valve and may be made completely, or at least partly of a plastics material.

The or each coupling may be made from a metallic material such as brass, copper, iron, stainless steel or any other suitable electrically conductive material.

The fitting may have two couplings, each having at least a part made of electrically conductive material, attached thereto by said at least one retaining member and the or each retaining member may have an electrically conductive part to effect an electrical connection between said parts of the coupling made of electrically conductive material.

The retaining member may comprise a strap or band which may be made of metal such as brass connected, for example by brazing, to a coupling and the straps being adapted to co-operate to encompass a part of the fitting and to be connected together to clamp the part of the fitting therebetween and thus connect the couplings to the fitting.

The retaining means may detachably connect a coupling or couplings to the fitting.

Accordingly, if it is desired a fitting may have an existing coupling which is connected thereto replaced by a different form of coupling, for example, to accommodate a different size of element such as a water flow pipe.

The connection between the straps may include a fastening means which may be adapted to permit an electrical conductor to be connected thereto.

For example, where the fitting is a plumbers fitting such as a valve to control water flow at least the external body of the valve may be made of a synthetic plastics material and two couplings by which water flow pipes are connected to the valve may be made of brass. Such a fitting has the advantage that the body may be made of synthetic plastics material which is adequately strong for its purpose and is relatively economical whereas the couplings are made of brass which is adequately strong to withstand the loads imposed thereon in service.

Preferably sealing means are provided to ensure sealing engagement between said fitting and the or each coupling.

Conveniently said sealing means may comprise an 0-ring made from an elastomeric material such as neoprene.

The invention will now be described by way of example with reference to the accompanying drawings wherein, FIGURE 1 is a vertical cross-section through a valve body embodying the invention; FIGURE 2 is a section on the line A-A of Figure 1: FIGURE 3 is a side elevation of a coupling and retaining member for use with the body shown in Figures 1 and 2; FIGURE 4 is a view of the valve body and coupling members shown in Figures 1 to 3 shown in connected position: FIGURE 5 is a view of an alternative valve shown schematically having conductive members secured therein; FIGURE 6 is an end view of the valve shown schematically in Figure 5.

Referring to the drawings a fitting 10 comprises a valve having a valve body 11 made as a moulding in suitable synthetic plastics material such as nylon. The detailed construction of the valve body and the other components of the valve are not particularly significant in the present invention and hence will not be described further.

The valve body is provided with a first cylindrical recess 12 and a diametrically opposite second cylindrical recess 13 within each of which is received a nose part 14 of an inlet and outlet coupling 15. One such coupling is shown in Figure 3 and it will be appreciated that the other coupling is identical. A nose part 14 has an annular groove 16 therein in which is received a conventional 0 ring, not shown, to provide a liquid tight connection between the nose part 14 and the cylindrical surface of the respective recess 12, 13.

The nose part 14 is connected to or formed integrally with the male part 17 of a conventionally configured compression coupling having an external thread 18 with which a conventional compression coupling nut, not shown, may be engaged so as to connect a pipe to the fitting.

Alternatively, a conventional swivel joint may be connected to the external thread 18 to secure a pipe thereto.

The nose part 14 extends through a circular aperture 19 formed in a brass strap or band 20 of a shape which conforms to the shape of the body 11 in the region peripherally adjacent the recesses 12 and 13. The strap 20 is provided, at each end with outwardly extending lugs 21 which are apertured, as shown at 22.

To secure the couplings 15 to the valve body 11, the nose part 14 complete with 0-rings are inserted into the inlet and outlet recesses 12 and 13 as shown in Figure 4. Two bolts 24 pass through the respective aligned apertures 22 and lugs 21 and the couplings are secured to the fitting by tightening nuts 25 onto the bolts 24.

The straps associated with the inlet and outlet couplings engaged in the recesses 12 and 13 are hence fastened together to clamp the part 23 of the body 11 which is encompassed by the straps 20 therebetween so as to firmly attach the couplings 15 to the body 11.

The couplings now firmly secured to the fitting also, provide an electrically conductive path between the inlet and the outlet providing the bolts are made from an electrically conductive material.

The sealing of the couplings 15 to the fitting by the provision of the 0rings enables the couplings to absorb shock and minor displacement or distortion relative to the fitting without impairing the fluid-tight engagement between the coupling and the fitting.

By virtue of making the body 11 as a moulding in a suitable synthetic plastics material the body can be made economically whilst by providing the couplings in a suitable strong material, such as brass, the connections can withstand the loads imposed upon them in use. For example, the considerable tightening torque conventionally applied by a plumber when tightening a compression joint which they may not be able to accommodate if made of an economically suitable synthetic plastics material.

Furthermore, the body may be provided with a desired pair of couplings without requiring any modification to the body. Moreover, a body provided with a particular pair of couplings may have one or more of the couplings replaced by a different coupling or couplings for example, a coupling to accommodate a different size of pipe. Still further, if a coupling becomes damaged in use, it may be replaced.

In addition, the attachment members provide an electrical connection between the inlet and outlet couplings thereby effecting an electric connection between the couplings irrespective of the electrically insulating properties of the body.

One or both of the fastenings which clamp the lugs 21 together may be used to attach a further electrical connection, for example an earth connection of an electric circuit, to the fitting.

Referring now to Figures 5 and 6, an alternative fitting is shown. The fitting comprises a body 30 and couplings 31 and 32.

The body 30 is made from a plastics material and has either moulded therein or subsequently inserted therein two tube-like members 33 made from an electrically conductive material such as copper or brass. Each tube-like member 33 has a threaded portion at each end thereof.

The couplings 31 and 32 are each provided with a flange 34 and 35 respectively, which flange is made from an electrically conductive material, for example copper or brass. The flange 34 is provided with a pair of apertures 36 and 37 and the flange 35 is also provided with a pair of apertures 38 and 39.

To secure the couplings 31 and 32 to the body 30 of the fitting the couplings are placed into position, as shown in Figure 5. Threaded fasteners 40 and 41 are then passed through the apertures 36 and 37 to secure the inlet coupling 32 to the body. The threaded fasteners engage within the threaded portion of the electrically conductive tube-like members 33.

The outlet coupling is similarly secured to the body 30 by fasteners 42 and 43 passing through the apertures 38 and 39 in the flange 35 and engaging with the threaded end portions of tube-like members 33.

The couplings are thus firmly secured to the body of the fitting, the 0rings illustrated providing sealing engagement between the couplings and the fitting and the provision of the electrically conductive tube-like members 33 and the electrically conductive couplings 31 and 32 ensuring that electrical continuity can be made between any pipes connected to the couplings 31 and 32.

It will be appreciated that in the embodiment shown, the tube-like members do not have to be secured relative to the body but merely located therein since the connection of the couplings to the tube-like members 33 will ensure that they remain securely in position.

The valve body may be any desired valve such as a stop cock or a valve in an electric water heater or a shower or the like. Although the example described hereinbefore is a fitting in a domestic or industrial plumbing system the invention may be applied to other fluid flow systems where the fluid is, for example, hydraulic fluid or gaseous fluid such as air.

Although it is preferred that the part of the fitting with which the couplings are engaged is made of plastics material which is electrically insulating the invention may be applied to a fitting the body of which is made of an electrically conductive material there being retained the advantages of interchangability of the couplings and also the possibility of making the couplings of a different material, for example a different metal such as brass, instead of a metal, such as aluminium, of which the body is made since the metal of which the couplings are made may be more suitable for that purpose than the metal of which the body is made.

Although in the present example the couplings may be compression fittings, where a nut when screwed onto a male thread on the coupling deforms a sealing member such as a copper olive onto a pipe to be connected to the coupling to secure the pipe to the coupling in a fluid type fashion other coupling arrangements may be provided.

If desired the retaining member may comprise other than a brass strip.

For example, retaining member may comprise a strip of electrically insulating material which may itself be provided with a separate electrical conductor in those cases where it is desired to connect the coupling in an electric circuit. In such a case alternatively, a separate electrical connection may be provided.

If desired only parts of the fittings may be made of electrically insulating material and if such parts interrupt electrical connection with a coupling the or at least one retaining member may be electrically conductive to provide an electric connection to the or at least one coupling member.

The features disclosed in the foregoing description, or the accompanying drawing, expressed in their specific forms or in terms of a means for performing the disclosed function, or a metal or process for attaining the disclosed result, or a class or group of substances or compositions, as appropriate, may, separately or any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

CLAIMS:

1. A fitting made at least in part of an electrically non-conductive material, said fitting being provided with a coupling, at least part of which is made from electrically conductive material.

2. A fitting according to Claim 1 wherein said coupling is secured to said fitting by a retaining member made from electrically conductive material.

3. A fitting according to Claim 2 wherein said fitting is provided with a pair of couplings and wherein said at least electrically conductive part of said couplings are connected to each other through the or each electrically conductive retaining member.

4. A fitting according to Claim 3 wherein said pair of couplings are connected to each other in a manner to secure said couplings to said fitting.

5. A fitting according to Claim 1 or Claim 2 wherein said fitting is provided with a part made of an electrically conductive material and wherein the or each coupling is connected at least electrically to said electrically conductive material.

6. A fitting according to Claim 5 wherein said fitting is made of a plastics material and said part of electrically conductive material is secured therein.

7. A fitting according to any one of the preceiding claims wherein said fitting is adapted for use in a fluid flow circuit.

8. A fitting according to Claim 7 wherein said fitting comprises a fluid flow valve.

9. A fitting according to any one of the preceding claims wherein said fitting is made primarily from a plastics material.

10. A fitting according to any one of the preceding claims wherein the or each coupling is made primarily of a conductive material.

11. A fitting according to Claim 10 wherein said coupling is made from brass.

12. A fitting according to any one of the preceding claims wherein the or each coupling is provided with sealing means to enable sealing engagement between said coupling and said fitting.

13. A fitting according to Claim 12 wherein said sealing means comprises an 0-ring.

14. A fitting according to any one of the preceding claims wherein said fitting is provided with two couplings connectable to each other through said retaining members, connection of said retaining members to said coupling attaching said couplings to said fitting.

15. A fitting substantially as hereinbefore described with reference to and as illustrated in Figures 1 to 4 of the accompanying drawings.

16. A fitting substantially as hereinbefore described with reference to and as illustrated in Figures 5 and 6 of the accompanying drawings.

17. A fitting including any novel feature or novel combination of features disclosed herein and/or illustrated in the accompanying drawings.