GB2135615A

GB2135615A - Improvements relating to spanners

Info

Publication number: GB2135615A
Application number: GB08403493A
Authority: GB
Inventors: Philip Corke; William Glyndwr Jones
Original assignee: Design & Manufacture Ltd
Current assignee: Design & Manufacture Ltd
Priority date: 1983-02-16
Filing date: 1984-02-10
Publication date: 1984-09-05
Also published as: GB8403493D0

Abstract

A spanner is designed for fitting connectors between main electrical cable conduits (1) and their branches (6), such connectors having a hex head (9) which has to be gripped within the main conduit. The spanner has an elongate body (11), tubular at the grip end (12) and merging into a U-shape (13) at the other end, the flanges of the U being locally extended by lugs (14) to form one of the jaws. The other jaw (17) is provided by a cylindrical pin which is a bent out extremity of a rod (16) lying along within the spanner body and adjustable by a screw device (18, 19) at the grip end. This other jaw (17) or pin is maintained in its correct attitude by the flanges of the U, while its cylindrical outer surface has comfortable engagement with the interior of a tubular connector. <IMAGE>

Description

SPECIFICATION Improvements relating to spanners This invention relates to spanners. It is primarily concerned with a spanner for use in making a connection between ductwork for electrical cables and branch conduits through which individual cables are led off from the main duct.

Such ductwork is generally in the form of channel members with inturned flanges along the free edges. A cover strip may be secured to these.

It is fixed to a wall or ceiling by fasteners through its base, and where a branch conduit is required a hole is provided in one of the flanges. A connector in the form of an externally screw-threaded tubular spigot with a hexagonal head at one end is passed through such a hole from inside the duct, so that the shoulder below the head engages the inside of the flange. The conduit can then be screwed on to the projecting spigot or the spigot into the end of the conduit. This requires the head to be gripped. The confined space inside the duct and the inturned flanges make it impossible to use conventional spanners of the flat or socket type effectively, and many fitters improvise with screwdrivers and hammers, often with harmful results.

It is therefore an aim of this invention to provide a tool capable of gripping and manipulating such a connector.

According to the present invention there is provided an adjustable spanner comprising an elongate body for gripping at one end and jaws generally transverse thereto at the other end, one of said jaws having a working surface convex in cross-section.

Preferably, said one jaw will be movable in relation to the body of the spanner while the other jaw can be integral therewith.

For the connector referred to previously, said one jaw will be on the remote side of the other jaw in relation to the grip end and will be entered into the spigot from the head end while the other jaw engages the periphery of the head, but only over a limited extent on one side, towards the mouth of the channelled ducting.

Conveniently, said one jaw is an element at the end of a longitudinal adjustment member housed largely within the body. It may take the form of a cylindrical pin provided by the end portion of a rod bent substantially at right angles to the main portion, which extends down inside the body towards the grip end. There it can have screwthreaded engagement with an adjusting nut or bolt and a spring may be fitted to urge the jaws apart against the screw adjuster.

The body is preferably tubular at the grip end, merging into U-shape at the jaws end. The other jaw may then be provided by lugs locally extending the U-section, while said one jaw is kept in alignment by being at least partially embraced by the flanges of the U-section.

For a better understanding of the invention one constructional form will now be described, by way of example, with reference to the accompanying drawing, in which: Figure 1 is a perspective view of a junction being made between cable ducting and a branch conduit, using a spanner according to the invention, Figure 2 is a perspective view of the spanner body, and Figure 3 is a cross-section of the jaws end of the spanner.

Cable ducting is in the form of a U-shaped channel member 1 with a base 2 fixed to the wall, upper and lower flanges 3, 4 and an inturned narrow flange or rim 5, at least on the lower flange, narrowing the mouth of the channel. A branch conduit 6 is to carry a cable down from the ducting and is fitted to the lower flange by a connector 7. This is a tubular member with an externally screw-threaded spigot 8 and a hexagonal head 9. The spigot passes closely through a hole in the lower flange 3 from inside the ducting until the shoulder below the head 9 bears on the inside of the flange. The upper end of the conduit 6 is internally screw-threaded to receive the spigot.

Generally it will be the connector 7 that is turned to make the connection tight. A spanner 10 for doing this has an elongate body 11 with a tubular handle portion 12 at one end and a Usection portion 1 3 at the other, these merging together at about the mid-length. A short distance back from the extreme end of the portion 1 3 there are lugs 1 4 integrally formed from the body, locally extending the U-section. These together form a jaw of the spanner.

A rod 1 5 bent into an L-shape has its main, longer arm 1 6 extending down the body from the U-section end, with its short arm 17, confined by the flanges of that end, projecting proud of them.

This arm 1 7 is a cylindrical, pin-like member which forms the other jaw of the spanner. It can be adjusted by a knob 1 8 which forms the head of a screw 19 threaded into the end of the main arm 1 6, within the tubular portion 12. The shaft of the screw 1 9 passes through a guide-ring 20 captive within the portion 12, and a coil spring 21 surrounding the shaft acts between this ring and the end face of the rod 1 5 to urge the jaws apart and keep the knob 18 firmly against the end of the body 11.

In use, the pin 17 is entered into the bore of the connector 6 until the shoulders adjacent the lugs 14 bear on the head 9, and the knob 18 is turned to tighten the lugs against the periphery of the head. They may both engage the same flat, or they may engage adjacent ones. The spanner can therefore be set on the head with finer angular adjustment than one with normal, parallel jaws, an advantage when it can only have a limited arc of movement.

As well as adjustment for this purpose, the spanner can of course be used on a range of differently sized connectors.

Claims

1. An adjustable spanner comprising an elongate body for gripping at one end and jaws generally transverse thereto at the other end, one of said jaws having a working surface convex in cross-section.

2. A spanner as claimed in claim 1, wherein said one jaw is movable in relation to the body of the spanner.

3. A spanner as claimed in claim 2, wherein the other jaw is integral with said body.

4. A spanner as claimed in claim 1, 2 or 3, wherein said one jaw is on the remote side of the other jaw in relation to said one end.

5. A spanner as claimed in any preceding claim, wherein the adjustment is provided by screw means at said one end.

6. A spanner as claimed in any preceding claim, wherein spring means urge the jaws apart.

7. A spanner as claimed in any preceding claim, wherein said one jaw is an element at the end of a longitudinally extending adjustment member housed largely within the body.

8. A spanner as claimed in claim 7, wherein said one jaw is a cylindrical pin provided by the end portion of a rod bent substantially at right angles to the main portion, which extends down inside the body towards the grip end.

9. A spanner as claimed in claim 7 or 8, wherein the body is tubular at the grip end, merging into U-shape at the jaw end.

10. A spanner as claimed in claim 9, wherein said other jaw is formed by lugs locally extending the U-section.

1 A spanner as claimed in claim 9 or 10, wherein said one jaw is kept in alignment by being at least partially embraced by the flanges of the U-section.

1 2. A spanner substantially as hereinbefore described with reference to the accompanying drawing.