GB2060275A

GB2060275A - Two-part electrical coupling

Info

Publication number: GB2060275A
Application number: GB7934425A
Authority: GB
Original assignee: Smiths Group PLC
Current assignee: Smiths Group PLC
Priority date: 1979-10-04
Filing date: 1979-10-04
Publication date: 1981-04-29
Also published as: GB2060275B

Abstract

Two-part electrical couplings for screening leads of the kind having a number of individual pin or socket terminals in one coupling part, the other coupling part providing complimentary pins and/or sockets, has an earth continuity connection comprising a screen termination ring (19) of a size adapted to be introduced between adjacent ends of said screening (8) and said one coupling part (1, 11) to provide an electrical connection there-between, a flying lead (21) electrically connected to said termination ring, and a pin or socket connector (18) electrically connected to the free end of said flying lead, the arrangement being such that the flying lead can be readily bent around to introduce its pin or socket into a required axially extending pin or socket location within said one coupling part. <IMAGE>

Description

SPECIFICATION Improvements relating to two-part electrical couplings This invention relates to two-part electrical couplings for screened leads and has application to couplings of the kind in which a number of individual leads, e.g. a wire harness, provide terminals in the form of pins or sockets in one coupling part, the other coupling part providing complimentary pins and/or sockets.

To ensure the complete absence of electrical interference it is necessary to ensure earth continuity of the screening and many arrangements are known to provide an adequate earth continuity between the screening and the body of the coupling part to which it is connected.

An object of the present invention is to provide an arrangement in which earth continuity can be achieved reliably and simply between the screening and a pin/or socket of its coupling part.

According to one aspect of this invention there is provided an earth continuity connection for a two-part electrical coupling for screened leads of the kind in which a number of individual leads are provided which present terminals in the form of pins or sockets at spaced axially extending positions in one coupling part, the other coupling part providing complimentary mating pins and/or sockets, said connection comprising a screen termination ring of a size adapted to be introduced between adjacent ends of said screening and said.

one coupling part to provide an electrical connection there-between, a flying lead electrically connected to said termination ring, and a pin or socket connector electrically connected to the free end of said flying lead, the arrangement being such that the flying lead can be readily bent around to introduce its pin or socket into a required axially extending pin or socket location within said one coupling part.

According to a second aspect of this invention, there is provided an electrical two-part coupling for screened leads of the kind in which a number of individual leads are provided which present terminals in the form of pins or sockets at axially spaced positions in one coupling part, the other coupling part providing complimentary mating pins and/or sockets, fitted with an earth continuity connection according to the first aspect of the invention.

Preferably, said screening encloses a conduit of protective material for the individual leads e.g. a material such as "PTFE", which is resistant to most chemicals and contaminents. In such a case, adjacent ends of the conduit and screening may conveniently be fixed to a tubular metallic end fitting one end of which provides an annular abutment surface, between which and a complimentary end surface of said one coupling part, the screen termination ring is sandwiched.

In order that the invention may be readily understood, a two-part electrical coupling incorporating an earth continuity connection in accordance with the invention, will now be described with reference to the accompanying drawings in which: Figure 1 is a fragmentary half-sectional view of one part of the coupling, Figure 2 is a view of the screen termination ring used with the coupling, and, Figure 3 is a view of a modified screen termination ring.

Referring to Figure 1, only one part of the two part electrical coupling is shown which is itself in two pieces. One piece comprises a connector grommet 1 in the form of a casing filled with moulded insulating material defining a number of spaced generally axially extending apertures 2, into each of which the end of an electrical lead 3 is inserted, each lead end providing a bared end 4.

The other piece 11 comprises an outer casing 1 5 which encloses a moulded body 1 6 of insulating material, which body provides axially extending passages at positions complimentary to those of the connector grommet 1 in which socket or pin connectors 1 8 are located to which the bared ends 4 of respective leads 3 are crimped or soldered.

The electrical leads 3 are housed within a protective conduit 5 which is of a material, such as PTFE, to be resistant to most chemicals and contaminents. The end of the conduit 5 is rolled to provide a thread 6 by which it can be screwed onto a tubular end fitting 7. The screening for the conduit comprises a braided metal sleeve 8 fitting over the conduit 5, the end of which is detachably secured onto the end fitting 7 by a suitable securing clip 9. A preferred clip for this purpose, which enables the connection to be readily assembled in the field, is an "Oetiker" clip. In known manner such a clip comprises an oversized metal ring having a pair of opposed portions which can be pinched together to reduce the size of the ring radially and hence urge it into gripping contact with braided sleeve 8.The mouth of the end fitting 7 is flared as shown and provides a flange 10 which, when the two pieces 1 and 11 of said one coupling part are connected, abuts the adjacent end of the piece 1 via a sealing washer 12; the coupling pieces and the end fitting 7 are urged together by a back nut 13 which at one end is held slidably captive on the end fitting 7 between the clip 9 and flange 10. The back nut 13 threads onto a mating thread 14 provided on the outer casing 1 5.

Referring also to Figure 2, in accordance with the invention, an earth continuity connection is used to provide a positive connection between the braided screening sleeve 8 and a selected pin or socket connector 1 8 via the end fitting 7. This is achieved simply and reliably by the use of a screen termination ring 1 9 having three equi-spaced locating lugs 20 for locating over the end of the connector grommet piece 1 (in known couplings the end of this piece is usually provided with a number of flats around its circumference generally 6 or 12 flats); the lugs 20 are located on the ring 1 9 so that they slidably fit onto three spaced flats of the end piece, thereby to ensure that the ring is held positively against rotation on said end piece. An insulated flying lead 21 is connected at one end to the ring 1 9 and its other end presents a bared end 4a which can be readily crimped or soldered onto the required one of the socket or pin connectors 18, the flying lead being suitably bent round to lie within the mouth of the end fitting 7.

In a modification of the screen termination ring 19 shown in Figure 3, it may be formed with a skirt 22 which is pressed or otherwise has formed on its inner face a number of flats 23 to correspond with the flats provided on the coupling end, so as to provide a more positive location on the latter. Also, instead of providing a singie connecting tag on the ring 19, the ring is formed with an annular connecting skirt 24 so that the connection may be made at any appropriate point around the periphery.

Claims

1. An earth continuity connection for a two-part electrical coupling for screened leads of the kind in which a number of individual leads present terminals in the form of pins or sockets at spaced axially extending positions in one coupling part, the other coupling part providing complimentary mating pins and/or sockets, said connection comprising a screen termination ring of a size adapted to be introduced between adjacent ends of said screening and said one coupling part to provide an electrical connection there-between, a flying lead electrically connected to said termination ring, and a pin or socket connector electrically connected to the free end of said flying lead, the arrangement being such that the flying lead can be readily bent around to introduce its pin or socket into a required axially extending pin or socket location within said one coupling part.

2. An earth continuity connection as claimed in Claim 1 , wherein the screen termination ring has three equi-spaced locating lugs for locating onto three spaced flats at the end of a connector grommet piece normally forming part of said twopart coupling.

3. An earth continuity connection as claimed in Claim 1, wherein the screen termination ring is formed around its inner periphery with a skirt which presents a number of flats on its inner face for locating onto corresponding flats of a connector grommet piece normally forming part of said two-part coupling.

4. An earth continuity connection as claimed in Claim 2 or 3, wherein the screen termination ring is formed around its outer periphery with a further skirt to which the flying lead can be attached at any appropriate point.

5. An electrical two-part coupling for screened leads of the kind in which a number of individual leads are provided which present terminals in the form of pins or sockets at axially spaced positions in one coupling part, the other coupling part providing complimentary mating pins and/or sockets, fitted with an earth continuity connection according to Claims 1 to 4.

6. A two-part coupling according to Claim 5, wherein said screen encloses a conduit of protective material for the individual leads which is resistant to most chemicals and contiminents, and where adjacent ends of the conduit and screening are fixed to a tubular metallic end fitting, one end of which provides an annular abutment surface, between which and a complimentary end surface of said one coupling part, the screen termination ring is sandwiched.

7. A two-part electrical coupling constructed, arranged and adapted for assembly substantially as hereinbefore described with reference to the accompanying drawing.