GB2355863A

GB2355863A - Electrical earth connector

Info

Publication number: GB2355863A
Application number: GB9925366A
Authority: GB
Inventors: Roger Timothy Chew
Original assignee: Philex PLC
Current assignee: Philex PLC
Priority date: 1999-10-27
Filing date: 1999-10-27
Publication date: 2001-05-02
Anticipated expiration: 2019-10-27
Also published as: GB2355863B; GB9925366D0

Abstract

An electrical earth connector comprises a body 6 having a channel (2) in it, a bolt (13), and one or two clamping plates 8 and 10. The body has teeth 5 to bite into a metallic member, such as a radiator fin, placed in the channel. Tightening the bolt causes plate 8 to clamp against the metallic member. An earthing lead can be connected, either by placing it too in the channel or by placing it between plates 8 and 10 - either way, the connector and the lead can be fitted by tightening a single bolt.

Description

2355863 ELECTRICAL EARTH CONNECTOR

Field of the Invention

The present invention relates to connectors for electrically earthing metallic items such as, for example, central heating radiators and other electrically conductive household or industrial items that if electrified could otherwise present a hazard.

Backaround to the Invention

Electrical earth connectors are a commonplace safety feature associated with metallic pipework such as central heating plumbing in both domestic and industrial environments. One particularly important role that they perform is to protect against the risks of electrification of the pipework and radiators in the case that mains electrical cables are accidentally exposed and come into contact with the pipework.

The conventional approach to suitably earthing radiators and the like, generally involves dismounting the radiator, or other metallic item to be earthed, and fastening an earthing connector with an earthing lead to the mounting before putting the radiator, or other item, back into place.

In the prior art proposals have been made for simplifying the task by providing electrical earth connectors that are adapted to be screw clamped to a radiator, fin or other sheet metal element and in which one screw grinds into the radiator fin to make electrical contact and hold the connector in place while another screw is provided for mounting of an earthing lead. Such connectors are a substantial improvement on the commoner earthing connectors but require two screws independently adjusted in order to secure the connector and earthing lead in place. Furthermore, the point of contact with the radiator fin or other metallic member is localised to the end of this screw.

It is a general objective of the present invention to provide an electrical earthing connector that may be installed quickly and simply and may be easily adjusted and which suitably has well distributed points of contact with the radiator fin or other metallic member.

1 Summa[y of the Invention According to a first aspect of the present invention there is provided an electrical earth connector which comprises a rigid connector body defining a channel therein, a clamping bolt means threadedly engaged with a threaded aperture in the body intersecting the channel and having a clamping plate thereon at the end of the bolt within the channel and extending transversely of the bolt, the bolt being rotatable within its mounting to the clamping plate whereby tightening of the bolt advances the plate across the channel to clamp a radiator fin or other metallic member slotted within the channel, in use, against an opposing wall of the channel and further to clamp an earthing lead in place within the connector, the connector body having one or more sharp projections to bite into the radiator fin or other metallic member and providing a path for conduction of electricity from the radiator fin or other metallic member therethrough and to the earthing lead.

In one preferred embodiment the one or more sharp projections, or "teeth", project from the opposing wall of the channel, Preferably there are several such projections at spaced intervals on the opposing wall of the channel. By providing multiple such teeth spaced apart on the opposing wall of the channel the effect of any localised obstructions to good electrical contact can be minimised.

Preferably the connector has in addition to said clamping plate a further clamping plate that is held captive relative to the said clamping plate and generally plane parallel therewith and slidably movable towards or away therefrom whereby the said clamping plate may be advanced across the channel toward the said further clamping plate to grip an earthing lead therebetween and to grip a said radiator fin or a said other metallic member against the opposing wall of the channel between the further said clamping plate and the opposing wall of the channel.

Preferably the clamping plate and/or the further clamping plate is/are mounted directly or indirectly to the clamping bolt with a degree of freedom to move in a 2 rocking motion. This facility enables the connector to accommodate for uneven surfaces to be clamped.

Brief description of the drawings

Preferred embodiments of the present invention will now be more particularly described, by way of example, with reference to the accompanying drawings, wherein:

Figures 1A-11) are, respectively, rear, side, bottom and front elevation views of a connector body forming a component of a connector of the present invention; Figures 2A-21D are, respectively, rear, side, bottom and front elevation views of a secondary clamping plate of the connector; Figure 3A and 3B are, respectively, a rear elevation view and transverse sectional view of a primary clamping plate of the connector; Figures 4A-4C are, respectively, a rear elevation view, a side elevation view and a 20 front elevation view of a clamping bolt of the connector; Figure 5 is a part cut away view similar to that of Figure 4B but showing the primary clamping plate secured to the clamping bolt by the compressed rivet end of the clamping bolt; Figures 6A and 6B are, respectively, a side elevation view and top plan view of the assembled connector.

Description of the preferred embodiments

Referring firstly to Figures 1 A to 1 D, the connector body 1 is a rigid generally Ushaped structure that is suitably formed of metal or metal alloy and having a central channel 2 defined between a front wall 3 and opposing wall 4 which is separated by a stepped base wall 6. The front wall 3 is referred to as "front" only for convenience 35 and may, of course, face in any orientation subject to where it is installed.

3 The front wall 3 has a threaded aperture 7 extending through it toward the channel 2 and opposing wall 4 and is adapted to receive and screw threadedly co- operatively engage with the threaded shank 15 of clamping bolt 13 as illustrated in Figures 6A and B. The opposing wall of the connecter body 1 notably has a set of four sharp projections 5 facing inwardly of the channel 2 toward the front wall 3. These sharp projections 5 serve as teeth that bite into the radiator fin or other metallic member that the connector is mounted to in use.

Turning to Figures 2A to 2D, these illustrate another U-shaped component of the connector made of metal or metal alloy - in this case the secondary clamping plate 8 that in use closely opposes the opposing wall 4 of the connector body to clamp the radiator fin 17 or other member therebetween within the channel 2, as can best be seen in Figure 6.

The secondary clamping plate 8 has large rectangular apertures 9 in its front and rear faces. These apertures 9 are mounting apertures by means of which the secondary clamping plate 8 may be captively mounted to the primary clamping plate that is illustrated in Figures 3A and 3B.

In the assembled connector as illustrated in Figures 6A and 6B the secondary mounting plate 8 can be seen coupled to the primary mounting plate 10 with the lugs 11 of the primary mounting plate 10 projecting through the respective apertures 9 of the secondary mounting plate 8. This relative loose coupling of the primary 10 and secondary 8 mounting plates enables a secondary mounting plate 8 to move forwardly across the channel 2 to a limited extent ahead of the primary mounting plate 10 to enable an earthing lead 18 to be inserted between the primary clamping plate 10 and secondary clamping plate 8 and the primary clamping plate 10 to then be advanced to clamp the earthing lead 18 against the secondary clamping plate 8 and, in turn, to press the secondary clamping plate 8 against the radiator fin 17 and then against the sharp projections 5 thereby clamping the whole connector with the earthing lead onto the radiator.

4 The primary clamping plate 10 in the assembled connector is mounted to the end of the clamping bolt 13 that projects into the channel 2 of the connector body 1. As can be seen from Figure 5, the outer end of the clamping bolt 13 has a hexagonal head 14 to enable it to be turned by a spanner. Suitably it may be adapted to be turned substantially solely by a dedicated spanner in order to minimise the risk of tampering.

The alternate end of the clamping bolt 13 has a narrow tip that is adapted to serve as a rivet joint 16 that co-operatively engages with a counter-sunk aperture 12 in the primary clamping plate 10. Sufficient clearance is provided between the rivet formation 16 of the end of the clamping bolt 13 and the corresponding socket 12 of the primary clamping plate 10 to allow for relatively free relative rotation therebetween. This enables the clamping bolt 13 to be rotated within the screw threaded aperture 7 of the connector body I and thereby advance therethrough or retract therefrom. In the assembled connector although the clamping bolt 13 is free to rotate in the threaded aperture 7 and socket 12 of the primary clamping plate 10 the primary clamping plate 10 and the secondary clamping plate 8 are themselves prevented from rotating by the base wall 6 of the connector body 1.

As will be appreciated, the configuration of the present invention allows the connector to be mounted to the radiator fin or other metal member and clamped in place simultaneously clamping the earthing lead without need for two independent screwing operations, and the provision of the spaced apart teeth 4 provides a broadly distributed set of points of contact with the metal of the radiator fin or the like. This has been found to be extremely efficient and effective in use.

The degree of freedom of the primary and secondary clamping plates to rock relative to the longitudinal axis of the clamping bolt 13 is a further useful feature that enables the connector to accommodate for uneven surfaces of the earthing lead 18 and the radiator fin 17.

Although the present invention has been described above with respect to one preferred embodiment numerous alternative embodiments are conceivable within the scope of the invention. These may include, for example, arrangements in which there are one or more teeth provided on the secondary clamping plate rather than the primary clamping plate to clamp the earthing lead in place and to secure the connector to the radiator fin or other metallic member.

6

Claims

Claims

I An electrical earth connector which comprises a rigid connector body defining a channel therein, a clamping bolt means threadedly engaged with a threaded aperture in the body intersecting the channel and having a clamping plate thereon at the end of the bolt means within the channel and extending transversely of the bolt means, the bolt means being rotatable within its mounting to the clamping plate whereby tightening of the bolt means advances the plate across the channel to clamp a radiator fin or other metallic member slotted within the channel, in use, against an opposing wall of the channel and further to clamp an earthing lead in place within the connector, the connector body having one or more sharp projections to bite into the radiator fin or other metallic member and providing a path for conduction of electricity from the radiator fin or other metallic member therethrough and to the earthing lead.

2. An electrical earth connector claimed in Claim 1, wherein the one or more sharp projections, or "teeth", project from the opposing wall of the channel.

3. An electrical earth connector as claimed in Claim 2, wherein preferably there are several such projections at spaced intervals on the opposing wall of the channel.

4. An electrical earth connector as claimed in any preceding claim, wherein the connector has in addition to said clamping plate a further clamping plate that is held captive relative to the said clamping plate and generally plane parallel therewith and slidably movable towards or away therefrom whereby the said clamping plate may be advanced across the channel toward the said further clamping plate to grip an earthing lead therebetween and to grip a said radiator fin or a said other metallic member against the opposing wall of the channel between the further said clamping plate and the opposing wall of the channel.

7 5. An electrical earth connector as claimed in any preceding claim, wherein the clamping plate and/or the further clamping plate is/are mounted directly or indirectly to the clamping bolt with a degree of freedom to move in a rocking motion. 5 6. An electrical earth connector substantially as herein before described with reference to the accompanying drawings.

8 Amendments to the claims have been filed as follows Claims 1. An electrical earth connector for mounting to a radiator fin, pipe or other metallic member of an installation such as a central heating installion without need for dismounting a part of the installation, which connector comprises: a rigid connector body defining a U shaped channel therein, which is shaped to slot over a radiator fin, pipe or other metallic member of a said installation; a clamping bolt means threadedly engaged with a threaded aperture in the body intersecting the channel and having a clamping plate thereon at the end of the bolt means within the channel and extending transversely of the bolt means; the bolt means being rotatable within its mounting to the clamping plate whereby tightening of the bolt means advances the plate across the channel to clamp a radiator fin or other metallic member slotted within the channel, in use, against an opposing wall of the channel and further to clamp an earthing lead in place within the connector, the connector body having one or more sharp projections to bite into the radiator fin or other metallic member and providing a path for conduction of electricity from the radiator fin or other metallic member therethrough and to the earthing lead.
2. An electrical earth connector as claimed in Claim 1, wherein the one or more sharp projections, or "teeth", project from the opposing wall of the channel.
3. An electrical earth connector as claimed in Claim 2, wherein there are several such projections at spaced intervals on the opposing wall of the channel.
4. An electrical earth connector as claimed in any preceding claim, wherein the connector has in addition to said clamping plate a further clamping plate that is held captive relative to the said clamping plate and generally plane parallel therewith and slidably movable towards or away therefrom whereby the said clamping plate may be advanced across the channel toward the said further clamping plate to grip an earthing lead therebetween and to grip a said q.
radiator fin or pipe or a said other metallic member against the opposing wall of the channel between the further said clamping plate and the opposing wall of the channel.

An electrical earth connector as claimed in any preceding claim, wherein the clamping plate and/or the further clamping plate is/are mounted directly or indirectly to the clamping bolt with a degree of freedom to move in a rocking motion.
6. An electrical earth connector substantially as herein before described with reference to the accompanying drawings.

it.