GB2065994A

GB2065994A - Wedge for use in electric connectors

Info

Publication number: GB2065994A
Application number: GB8039551A
Authority: GB
Original assignee: BICC BURDNY Ltd
Current assignee: BICC BURDNY Ltd
Priority date: 1979-12-12
Filing date: 1980-12-10
Publication date: 1981-07-01
Also published as: GB2065994B

Abstract

A wedge forming part of an electrical connector of the tapered receptacle 3 and wedge 5 type is modified to provide on at least one of its wedge faces at least one cutting edge 6 capable of cutting and penetrating insulation 9 on the conductor it engages, and so making connection with the metallic conductor 10 therein. In this way, a wedge-type connector can be used on unstripped conductors. <IMAGE>

Description

SPECIFICATION Wedges for use in electric connectors This invention relates to wedges forming, or intended to form, part of an electrical connector and includes the wedges themselves, connectors incorporating them, the electric connecting method in which they are used, and the resulting connections.

In known technique for making connections between bare (or bared) conductors, two conductors are inserted in a tapered receptacle and a wedge is driven between them to connect them mechanically and electrically.

Conventionally, an explosive-actuated toolhas been used, but in another application being filed today (claiming priority from 7942768) we describe an alternative technique allowing hammering to be used effectively.

In accordance with the present invention, the wedge is modified in that at least one of its wedge faces incorporates at least one cutting edge capable of cutting and penetrating insulation on the conductor it engages and of making contact with the conductor therein.

The (or each) cutting edge may be longitudinal so as to cut like a knife; transverse or oblique so as to cut like a chisel; or curved (for example like a plough share). Especially (but not only) when longitudinal they may be serrated or subdivided.

The main application of connectors in accordance with the invention is in connecting a service tapping connector to an insulated (and possibly energised) main line, and in this case the tapping connector will usually be stripped at the end, so that the other wedge face can be of conventional concave form.

The main conductor may be a single insulated overhead line, or an insulated core of an underground or other distribution cable; an important application, however, is one in which the main conductor is a core of an aerial bundled distribution cable (with a long lay, allowing easy spreading of the conductors, and no overall sheath).

Apart from the provision of the cutting edge, the wedge may be of conventional design, and the receptacle may be of entirely conventional design; preferably however, the wedge and receptacle are generally as described in one or both of our applications nos. 7914543 and 7919682.

In the accompanying drawings Figure 1 illustrates a typical application of the invention, and Figures 2 and 4, 5 to 7, and 8 to 10 show three different forms of the invention.

Figure 1 shows a portidn of a bundled aerial conductor 1 consisting of four individually insulated conductors 2 laid up with a long lay length and without any common enclosure. A tapping connection is made to one of the four conductors by separating the conductors sufficiently to insert a C-section receptacle 3 with the conductor positioned in one of the ends. A tapping conductor 4, stripped at the end, is then inserted in the opposite (lower) end of the receptacle and a wedge 5 having an appropriate insulating piercing formation (not clearly shown in' Figure 1) is driven into the receptacle to make contact with both of the conductors and at the same time secure the parts in position.

Throughout the following description, the terms "upper" and "iower" refer to the orientation of the connector as shown in Figure 1.

Figure 2 is a transverse cross-section through the first form of connector in accordance with the invention, shown with the parts assembled but before the wedge is driven home; Figure 3 shows the upper part only of the connection as completed, and Figure 4 is a side elevation of the wedge 5. In this form of the invention, the upper edge of the wedge 5 is shaped to form two longitudinally continuous triangular section edges 6, spaced from the side faces 7 of the wedge and between them forming the effective upper wedge surface. On driving of the wedge, the sharp forward end 8 of each of these edges 6 penetrates the insulating covering 9 on the conductor 2 and becomes embedded in the metallic conductor 10 within (which may be stranded as shown or solid).

In this form of the invention, and in the others to be described shortly, the lower wedge surface 11 is of conventional concave form for contacting the stripped end of the tapping conductor 4 in the bottom of the receptacle 3.

Figures 5 to 7 are similar to Figures 1 to 4, save that the bottom part of the connector has been omitted from Figure 5. These Figures illustrate two independent modifications to the first form of the invention. Firstly guide splines 12 have been added to the upper corners of the wedge, and secondly the forward part of the piercing edges 6 have been formed into teeth 13 in order to provide multiple leading edges 8 to ensure cleaner slitting of the insulation 9.

In the remaining Figures, Figure 8 is a side view of a third form of the invention, and Figures 9 and 10 are respectively side and front elevations of the wedge used in this form of connection.

In this case both the wedge faces 11, 14 are concave, but the upper wedge face 14 is extended forwards to form a chisel edge 1 5 which cuts into the insulation 9 and pares back a section of it as shown at 1 5 in Figure 8 to gain the necessary access to the metallic conductor 1 0.

1. A wedge for an electrical connector which is modified in that at least one of its wedge faces incorporates at least one cutting edge capable of cutting and penetrating insulation on the conductor it engages and of making contact with the conductor therein.

2. A method of making a connection between two conductors, at least one of which is insulated, in which the two conductors are inserted in a tapered receptacle and a wedge is driven between them to connect them mechanically and electrically, the or each wedge face that engages an insulated conductor incorporating at least one cutting edge capable of cutting and penetrating

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Wedges for use in electric connectors This invention relates to wedges forming, or intended to form, part of an electrical connector and includes the wedges themselves, connectors incorporating them, the electric connecting method in which they are used, and the resulting connections. In known technique for making connections between bare (or bared) conductors, two conductors are inserted in a tapered receptacle and a wedge is driven between them to connect them mechanically and electrically. Conventionally, an explosive-actuated toolhas been used, but in another application being filed today (claiming priority from 7942768) we describe an alternative technique allowing hammering to be used effectively. In accordance with the present invention, the wedge is modified in that at least one of its wedge faces incorporates at least one cutting edge capable of cutting and penetrating insulation on the conductor it engages and of making contact with the conductor therein. The (or each) cutting edge may be longitudinal so as to cut like a knife; transverse or oblique so as to cut like a chisel; or curved (for example like a plough share). Especially (but not only) when longitudinal they may be serrated or subdivided. The main application of connectors in accordance with the invention is in connecting a service tapping connector to an insulated (and possibly energised) main line, and in this case the tapping connector will usually be stripped at the end, so that the other wedge face can be of conventional concave form. The main conductor may be a single insulated overhead line, or an insulated core of an underground or other distribution cable; an important application, however, is one in which the main conductor is a core of an aerial bundled distribution cable (with a long lay, allowing easy spreading of the conductors, and no overall sheath). Apart from the provision of the cutting edge, the wedge may be of conventional design, and the receptacle may be of entirely conventional design; preferably however, the wedge and receptacle are generally as described in one or both of our applications nos. 7914543 and 7919682. In the accompanying drawings Figure 1 illustrates a typical application of the invention, and Figures 2 and 4, 5 to 7, and 8 to 10 show three different forms of the invention. Figure 1 shows a portidn of a bundled aerial conductor 1 consisting of four individually insulated conductors 2 laid up with a long lay length and without any common enclosure. A tapping connection is made to one of the four conductors by separating the conductors sufficiently to insert a C-section receptacle 3 with the conductor positioned in one of the ends. A tapping conductor 4, stripped at the end, is then inserted in the opposite (lower) end of the receptacle and a wedge 5 having an appropriate insulating piercing formation (not clearly shown in' Figure 1) is driven into the receptacle to make contact with both of the conductors and at the same time secure the parts in position. Throughout the following description, the terms "upper" and "iower" refer to the orientation of the connector as shown in Figure 1. Figure 2 is a transverse cross-section through the first form of connector in accordance with the invention, shown with the parts assembled but before the wedge is driven home; Figure 3 shows the upper part only of the connection as completed, and Figure 4 is a side elevation of the wedge 5. In this form of the invention, the upper edge of the wedge 5 is shaped to form two longitudinally continuous triangular section edges 6, spaced from the side faces 7 of the wedge and between them forming the effective upper wedge surface. On driving of the wedge, the sharp forward end 8 of each of these edges 6 penetrates the insulating covering 9 on the conductor 2 and becomes embedded in the metallic conductor 10 within (which may be stranded as shown or solid). In this form of the invention, and in the others to be described shortly, the lower wedge surface 11 is of conventional concave form for contacting the stripped end of the tapping conductor 4 in the bottom of the receptacle 3. Figures 5 to 7 are similar to Figures 1 to 4, save that the bottom part of the connector has been omitted from Figure 5. These Figures illustrate two independent modifications to the first form of the invention. Firstly guide splines 12 have been added to the upper corners of the wedge, and secondly the forward part of the piercing edges 6 have been formed into teeth 13 in order to provide multiple leading edges 8 to ensure cleaner slitting of the insulation 9. In the remaining Figures, Figure 8 is a side view of a third form of the invention, and Figures 9 and 10 are respectively side and front elevations of the wedge used in this form of connection. In this case both the wedge faces 11, 14 are concave, but the upper wedge face 14 is extended forwards to form a chisel edge 1 5 which cuts into the insulation 9 and pares back a section of it as shown at 1 5 in Figure 8 to gain the necessary access to the metallic conductor 1 0. CLAIMS

2. A method of making a connection between two conductors, at least one of which is insulated, in which the two conductors are inserted in a tapered receptacle and a wedge is driven between them to connect them mechanically and electrically, the or each wedge face that engages an insulated conductor incorporating at least one cutting edge capable of cutting and penetrating the insulation on that conductor and of making contact with the conductor therein.

3. A wedge as claimed in Claim 1 or a method as claimed in Claim 2 in which the cutting edge is longitudinal so that it cuts like a knife.

4. A wedge as claimed in Claim 1 or a method as claimed in Claim 2 in which the or each cutting edge is transverse or oblique so that it cuts like a chisel.

5. A wedge as claimed in Claim 1 or a method as claimed in Claim 2 in which the or each cutting edge is curved.

6. A wedge or a method as claimed in anyone of the preceding claims in which the cutting edge is serrated or sub-divided.

7. A wedge or a method substantially as described with reference to Figures 2 to 4 or Figures 5 to 7 or Figures 8 to 10.

8. An electrical connection made using a wedge or a method as claimed in any one of the preceding claims.