GB2286728A

GB2286728A - Electrical connector

Info

Publication number: GB2286728A
Application number: GB9500765A
Authority: GB
Inventors: David Alan Croton; John Kitching; Trevor Elam
Original assignee: Sicame Electrical Developments Ltd
Current assignee: Sicame Electrical Developments Ltd
Priority date: 1994-01-15
Filing date: 1995-01-16
Publication date: 1995-08-23
Anticipated expiration: 2015-01-16
Also published as: GB2286728B; GB2294597A; GB2294597B; GB9500765D0; GB9600565D0

Abstract

An electrical connector is provided for connecting at least one conductor of a cable to the connector and to another conductor. The connector includes an open channel 8 to receive the cable and a sleeve 4 that is movable to enclose the cable in the channel. The sleeve 4 can slide along the connector between channel open and closed positions, while captured to the connector by a pin 14 and groove 12. Alternatively, the sleeve is resilient 47 and longitudinally slotted, to be sprung over the channel. A bridge cover 24, 51 can cover the channel and meet it with different angles of contact. The conductor is held in position by shear bolts 11, which can be staggered radially, and a second conductor can be provided into a through or blocked port 6 in a non open part 2, 55 of the connector. <IMAGE>

Description

Improvements Relating to Electrical Conductor Connectors This invention relates to improvements in connectors for the connection of conductors such as, for example, the ends of the conductor cores of electrical cables.

The invention is particularly directed toward the provision of connectors for the straight or in-line connection of the conductor cores of cables. There are currently available several different types of connectors for the purpose of connecting the conductor cores of cables. One such connector comprises a connector body with two longitudinal ports defined therein, each with an opening at respective ends of the connector for the reception of a cable conductor core.

The connectors are also provided with threaded apertures which pass into the ports for the reception of locking bolts therein which are tightened onto the cable conductor core ends to hold the same in position within the connector and electrically connect the same. A disadvantage with this form of connector is that, when used to connect higher voltage, ie 11/33kV, cables it is difficult to bend the second of the cables to be connected to a sufficient degree to allow the core to be inserted into the connector port.

This problem led to the development of a connector as described in British Patent no. GB2251984. This patent discloses the provision of a connector with at least one removable bridge cover such that the connector includes an open channel as opposed to a port for the reception of a cable conductor end therein. The provision of an open channel allows the conductor end to be placed in the channel without the need to bend or manipulate the cable to allow insertion. In order to allow the conductor end to be held in place the bridge cover is moved to lie over the open channel to close the same. A sleeve member is provided to slide into position over the bridge cover and the connector body to hold the cover in position and both the sleeve member and the bridge cover are provided with apertures for the reception of locking bolts to hold the sleeve, bridge cover and conductor end in a fixed position in relation to the connector body.

When one considers that each cable can have one, two, three or more conductors, each of which is required to be connected via a connector, it is clear that there is a need for an easy to use connector which uses a minimum of space.

There are at least five main disadvantages with this form of connector, the first is that the bridge cover and the sleeve tend to slip along the connector body and this can lead to a reduction in the fixing strength on the conductor end. In order to overcome this attempts have been made to provide location means between the bridge cover and the connector body but this requires further machining operations to be performed on the connector and increases the cost of production.

A second problem relates to the provision of the sleeve which is required to be moved from a position where it is located on the cable prior to the placing of the cable conductor end in the open channel on the connector, to a position to locate the bridge cover and conductor end in position. This causes considerable problems when the connectors are used for the connection of high voltage cables. These cables typically have a considerable amount of insulating material surrounding each conductor and the outer diameter of the cable is greater than the outer diameter of the connector. This means that the sleeve cannot be of sufficient diameter to pass over the cable and still provide secure location for the bridge cover and the conductor so that in order for the connector to be usable a section of insulating material adjacent the conductor end which is to be placed in the connector must be removed at least to a diameter which allows the sleeve to be placed thereon and then slid from the cable into place on the connector. This requirement is a serious disadvantage with the connector currently available as it leaves a section of cable core exposed after connection and represents an extra operation required during the connection of the cables.

The connection of the cable conductor ends is typically effected in situ and can be in areas with very limited access and in inclement conditions.

A third problem is that even when used with conductors having an insulation thickness such that the sleeve will pass over the same, there is a risk that the action of sliding the sleeve over the insulation may damage the insulation so as to produce longitudinal cuts or score marks in it. This is particularly likely where for instance the sleeve is a tight fit on the insulation or where the conductor itself has been bent in order such as is required to position it correctly relative to another to which it is to be joined. For conductors used at relatively high potentials such as ilks, any insulation damage is a potentially serious problem since it can lead to premature failure, and this is particularly the case with plastic insulation such as is used on certain new cable types.

A fourth problem is that of practical usage where, unless the person using the connector remembers to place the sleeve over the conductor before commencing the process of fitting the connector they will have to disassemble a partly completed connector to correct the omission. Indeed it is considered most desirable for connectors to have as few loose pieces as possible to reduce the risk of incorrect assembly.

A fifth problem is that in use of the conventional connectors an amount of conductor disturbance is unavoidable. For example when connectors as described in British patent no.

GB2251894 are used to connect the conductors of a cable having three of said conductors the conductors are arranged at 120 degrees angle relative to each other with the locking bolts used in each connector facing generally radially outwards from the centre point of the three conductors. All three conductors are positioned in their final positions with one conductor end placed in a port in a connector and prepared for the insertion of the second conductor end in the open channel at the other end thereof. Since the open channel into which the other conductor end is to be placed faces that part of the connector where the locking bolts are located, one of the following three methods has to be adopted in order to facilitate the placement of the conductor end in the open channel.

1) The second conductor end must be moved outwards from its final position and to one side before it is then placed in the open channel.

2) The first conductor end when positioned in the connector port must be moved inwards from its final position and to one side before being moved back such that the conductor can be positioned in the open channel.

3) The connector must be rotated on the first conductor end such that the open channel faces towards the centre point of the three conductors. However the bolts will also then be facing towards the centre point and hence be inaccessible for tightening. The first conductor end and the connector are then moved towards the centre line of the three conductors such that the second conductor enters the open channel. It is then necessary to rotate the connector again such that the bolts are again accessible for subsequent tightening.

All three of the above procedures necessitate moving both first and second conductor ends or moving the first conductor end initially outwards then inwards although it is particularly inconvenient to move conductors towards the centre point and may well be impossible because of restricted space or involves rotating the connector. All three methods are inconvenient and overly complicated.

The aim of the present invention is to avoid the disadvantages as described above and provide a connector for the connection of at least two cable conductors and to provide the connector with at least one open channel for the reception of an end of a conductor therein and to provide a sleeve member which is movable within the confines of the length of the connector.

The present invention provides a connector for the electrical connection of at least one conductor thereto, said connector comprising a body with at least one open channel for the location of a conductor end therein, and a sleeve member, said open channel and/or sleeve provided with at least one aperture for the location of a locking bolt therein and wherein the sleeve member is provided for movement between a first position on the connector body to allow the conductor end to be placed in the open channel, and a second position on said body to at least partially enclose said conductor end and open channel and allow electrical connection of the conductor end to the connector by insertion of the locking bolt to secure the conductor end in the connector.

In one embodiment of the invention the sleeve and body are provided with matching location means which define the path of the sleeve between the first and second positions and means for retaining the sleeve within the connector body length.

In one embodiment the location means comprise a pin provided in either of the body or sleeve and a longitudinal slot defined in the other, along which the pin slides. Preferably the longitudinal slot includes locking sections such that the pin can be locked in the first or second position until a positive movement is exerted thereon to release same from the locking section.

Preferably the sleeve is releasable from the locking position to allow the same to be removed from the second position to allow the conductor end to be released.

In one aspect of the invention the connector comprises a body with at least one open channel for the location of a conductor end therein; a bridge cover and a sleeve member, said sleeve and/or body and/or bridge cover provided with at least one aperture for the reception of a locking bolt therein to secure the conductor end and wherein the sleeve member is provided for movement between a first position on the connector body to allow the conductor end to be placed in the open channel and the bridge cover to be placed thereover and, a second position to at least partially enclose the bridge cover and allow electrical connection of the conductor end to the connector by insertion of the locking bolt to secure the conductor end in the connector.

In one embodiment when the bridge cover is placed on the open channel a substantially circular section port is formed and the side walls of the open channel rise to a point above the horizontal centre line of the same such that with the bridge cover removed a longitudinal slot is defined. Typically the angle of interface between the edge walls of bridge cover and the edge of the side walls of the open channel is between 0 and 180 degrees included angle. Preferably the included angle of the walls of the interface is 40 degrees. Preferably the width of the open channel elongate slot is substantially the same as the largest width of the cross section of the conductor end to be placed into the channel.

In one embodiment the connector body comprises an open channel at one end and a closed or straight through port at the other end such that a conductor end of a first cable can be slid into the port with a conductor end of a second cable placed into the open channel.

The connector body preferably includes at least one aperture for the reception of a locking bolt to secure a conductor end in the port at one end of the connector and at least one aperture to secure a conductor end in the open channel at the other end of the connector. Typically there is provided two sets of two apertures and both allow the insertion of locking bolts therein to secure the respective conductor ends and in one embodiment the apertures are threaded.

Preferably the sleeve member is provided with at least one aperture for the reception of locking bolts, provided such that when the sleeve is in a position substantially enclosing the open channel portions of the locking bolts can pass through the sleeve apertures to secure the conductor end in the open channel to electrically connect the end to the connector.

In one embodiment there is provided a first set of two apertures in the sleeve and a second set of matching apertures in the body and wherein the apertures in each set are axially and/or radially displaced.

Typically the locking bolts will have provision to shear at a specified torque and the conductors are the cores of electrical cables an end of which is insertable into the connector. In one embodiment the shear bolts are drivable by a tool to ensure the location of the plane of shear.

There is provided a method for the connection of two conductor'ends comprising placing an end of a first conductor into a port defined in one end of a connector and placing the end of the second conductor into an open channel defined in the other end of the connector, sliding a sleeve from a first position on the connector adjacent the open channel to a second position to substantially enclose the open channel and the sleeve and/or body are provided with apertures for the reception of locking bolts therein to secure and electrically connect the conductor ends to the connector and hence to each other.

The method also in one embodiment includes the intermediate step of moving a bridge cover into position over the open channel once a conductor end is in position therein and then moving the sleeve to the second position.

In a further aspect of the invention there is provided a connector comprising a connector body with at least one open channel therein, a bridge cover and a sleeve having a longitudinal aperture and wherein said sleeve is resiliently movable to locate the bridge cover on the connector body by pressing the connector body through the aperture to expand the same to contact and locate the sleeve with the bridge cover to hold the same in position on the connector.

Preferably the sleeve is formed from resilient sheet material such that the aperture returns to its original size after expansion.

Preferably the sleeve and bridge cover and/or connector body are provided with matching location means which when in engagement maintain the sleeve in a position locking the connector body and bridge in position.

In whichever embodiment of the invention it is preferred that both the port and open channel are provided with serrated inner surfaces to improve electrical contact and mechanical retention of the conductor ends.

Specific embodiments of the invention are now described with reference to the accompanying drawings wherein; Figures 1A, lB,lC and 1D illustrate the component parts of the invention in a first embodiment; Figures 2A, 2B and 2C illustrate end elevations of three alternative embodiments for the interface between the bridge cover and the walls of the open channel; Figures 3A, 3B and 3C illustrate the component parts of the connector in a second embodiment; Figures 4A, 4B and 4C illustrate component parts of the invention in a third embodiment; Figures 5A, 5B and 5C illustrate the connector in a further embodiment; Figure 6A illustrates an end elevation of the components of the embodiment shown in Figures 5A, 5B and 5C; and Figure 6B illustrates an end elevation of the asembled components of Figure 6A.

Referring firstly to Figures 1A, 1B, 1C, 1D there is illustrated the components of the connector of a first embodiment wherein the components are a connector body 2, a sleeve 4 and bridge cover 24. The connector body includes a port 6 which is shown including a block which is provided at the end of the port 6. The port 6 is provided for the reception of a first conductor end which in this case is a cable core end and the block is provided to prevent contamination between the port 6 and an open channel 8 at the other end of the connector provided for the reception of a second cable core end. The walls surrounding both the port and the channel have formed therein threaded apertures 10A, 10B which are adapted to allow locking bolts 11 to pass therein by screwing of the same such that continued screwing causes the bolts to and bite into and secure the conductor ends 20A, 20B as shown in Fig 1B to secure the same in the connector and hence achieve electrical contact and mechanical retention of the cores. The connector body is provided with at least one longitudinal slot 12 running at least partially along the length of the connector body for the reception therein of a pin 14A which is fitted into aperture 14 provided in the sleeve 4. The sleeve is also provided with apertures 16 which, when the sleeve is in its second position enclosing the bridge cover 24 and open channel 8, register with the apertures 10A on the body. Although not shown the invention is equally applicable when a straight through port 6, without a contamination block, is used and wherein the port joins into the open channel 8.

Screwing of the locking bolts 11 into the apertures 10A and 16, at least one set of which are threaded, secures the conductor end 20B in position in the connector. In this case the apertures are aligned longitudinally on the connector as in conventional connectors.

Figures lA, 1B, 1C and 1D show the components being assembled to form the connector. In Fig 1B the sleeve 4 is moved to its first position on the body 2. When in this position a pin 14A is knocked through an aperture 14 in the sleeve to pass into the slot 12 defined along the body 2 to form a guide and retension means to prevent relative rotation of the sleeve and body and define the path of the sleeve along the connector body. The sleeve is now permanently mounted on the connector body to be movable from a first position as shown in Figures 1B and 1C to a second position as shown in 1D.

With the cable core ends in position in the connector, the bridge cover 24 is moved into position to enclose the open channel 8 and cover the conductor end 20B as shown in Figs 1C and with the conductor end omitted in Fig 1D. With the bridge cover in position the sleeve 4 is moved along the slot 12 to a second position as shown in Figure 1D to lie over the bridge cover and conductor end and, by means of the insertion and tightening of the locking bolts 11, the conductor ends 20A, 20B and the bridge cover 24 are secured in position relative to the body 2. The completed connector is shown in Figure 1D with the exception that the bolts can be further driven to an extent that shearing of the bolt heads occurs to leave a substantially smooth surfaced connector.

Figures 2A, 2B and 2C illustrate alternative arrangements for the interface between the edges of bridge cover 24 and the connector body 2. In each embodiment the walls surrounding the open channel 8 pass the horizontal centre line 13 of the connector to form a slot 26 for the reception of a conductor end 20B and the slot is preferably of a width substantially the same as the width of the widest part of the cross section of the conductor end to be placed therein. In Figure 2A the angle of the walls is such that a 90 degree interface 27 is created by the insertion of the bridge cover 24 to close the slot 26. In Figure 2B the angle of the walls creates a 40 degree included angle interface 27' and in Figure 2C a O or 180 degree interface 27" is created. In the preferred embodiment of Figure 2B the angle of the interface is such that the bridge cover is drawn into location with the open channel walls to fit securely therein.

In the embodiment of the invention shown in Figures 3A, 3B and 3C, the pairs of apertures 10A, lOB and 16 are provided such that one of the apertures in each pair is axially and radially displaced from the other thus allowing the overall length of the connector to be reduced.

Figures 4A, 4B and 4C illustrate an end view of a third embodiment of the connector comprising a sleeve 33 in position over an open channel 35 in a connector body 37. The two components are shown individually in Figures 4B and 4C.

When fitted, the sleeve serves to provide a surface 39 against which the conductor end 20B is secured and electrical contact achieved by locking bolts 11 which pass into apertures 41 in the sleeve and threaded apertures 43 in the body which when tightened, serve to contact the conductor and secure the same in the connector against sleeve surface 39.

The inner surface 45 of the top of the sleeve acts against the body to provide a secure connector and achieve electrical connection.

Figures 5A, 5B,5C, 6A and 6B illustrate an alternative sleeve arrangement for a connector of the invention wherein the sleeve 47 is formed of resilient sheet material and is provided with a longitudinal aperture 49. In order to locate the bridge cover 51 in position the sleeve 47 is moved from a position as shown in Figures 5A, 5B and 6A as indicated by arrow 53 in Figure 6A in conjunction with the aperture being opened out to pass over the body 55 and cover 51 to contact and secure the bridge cover to hold the components in position as shown in Figures 5C and 6B. To increase the locating effect provided by the sleeve, location means 57A and 57B are provided to allow the sleeve, when in its holding position as shown, to be located in that position and restrain any movement of the bridge cover relative to the body.

The embodiments of the current invention provide a connector for the connection of the conductors such as the cores of electrical cables.Said connectors comprise at least one, but, if required, two, open channels which allow ease of insertion of at least one of the conductor ends. This connector eliminates the problems of conventional connectors with high voltage cables as discussed by providing a sleeve which in its second position holds the cable core and/ or bridge cover in position and wherein the sleeve is movable between a first position which is within the length of the connector to the said second position. The invention therefore eliminates the need for the sleeve to first be placed around the cable and then slid from the cable onto the connector and also the need to remove insulating material from high voltage cables due to the larger diameter of the cable relative to the sleeve. Indeed it is also apparaent that the ease of use of the connector according to the invention is improved over conventional connectors and furthermore that the resistance of the connector is not unduly affected by the number of interfaces between the components of the connector when connecting conductor ends in comparison with the conventional connectors. Therefore the advantages of the connector of this invention can be achieved without affecting the other required performance characteristics for connectors.

Claims

1. A connector for the electrical connection of at least one conductor thereto, said connector comprising a body with at least one open channel for the location of a conductor end therein, and a sleeve member, said open channel and/or sleeve provided with at least one aperture for the location of a locking bolt therein to secure said conductor end and wherein the sleeve member is provided for movement between a first position on the connector body to allow the conductor end to be placed in the open channel, and a second position on said body to at least partially enclose said conductor end and open channel and allow electrical connection of the conductor end to the connector by insertion of the at least one locking bolt to secure the conductor end in the connector.

2. A connector according to claim 1 wherein the sleeve and body are provided with matching location means which define the path of the sleeve between first and second positions.

3. A connector according to claim 2 wherein the location means include retention means for retaining the sleeve within the connector body length.

4. A connector according to either of claims 2 and 3 wherein the location means comprise a pin provided in either of the body or sleeve and a longitudinal slot defined in the other of the body or sleeve along which the pin slides.

5. A connector according to claim 4 wherein the longitudinal slot includes a locking section such that the pin is locked in the first and/or second positions until a positive movement is exerted thereon.

6. A connector for the electrical connection of at least one conductor thereto, said connector comprising a body with at least one open channel for the location of a conductor end therein; a bridge cover and a sleeve member, said sleeve and/or body and/or bridge cover provided with at least one aperture for the reception of a locking bolt therein, to secure the conductor end and wherein the sleeve member is provided for movement between a first position on the connector body to allow the conductor end to be placed in the open channel, and the bridge cover to be placed thereover, and a second position to at least partially enclose the bridge cover, and, in this position, allow electrical connection of the conductor end to the connector by insertion of the at least one locking bolt to secure the conductor end in the connector.

7. A connector according to claim 6 wherein with the bridge cover in position a substantially circular section port is formed and the side wall of the open channel rises to a point above the horizontal centre line of the same to define a longitudinal slot into the open channel and into which the conductor end is placed.

8. A connector according to claim 7 wherein the angle of interface between the edge walls of the bridge cover and the edge of the side walls of the open channel is between 0 and 180 degrees included angle.

9. A connector according to claim 8 wherein the included angle of the interface is 40 degrees.

10. A connector according to either of claims 8 or 9 wherein the width of the open channel aperture is substantially the same as the largest width of the cross section of the conductor end to be placed in the open channel.

11. A connector according to any of the preceding claims wherein the connector body comprises an open channel at one end for the reception of a first conductor end and a closed or straight through port at the other end for the reception of a second conductor end to provide electrical connection between the conductors.

12. A connector according to claim 11 wherein the connector body includes at least one aperture for the reception of a locking bolt therein to secure a conductor end in a port at one end of the connector and at least one aperture for the reception of a locking bolt to secure a second conductor end in the open channel at the other end of the connector.

13. A connector according to any of the preceding claims wherein the sleeve member is provided with at least one aperture for the reception of at least one locking bolt such that when the sleeve is in a position substantially enclosing the open channel of the body of the connector, a portion of the at least one locking bolt passes through the sleeve aperture to secure and electrically connect the conductor end to the connector.

14. A connector according to claim 13 wherein a first set of two apertures are provided on the sleeve and a second set of two matching apertures are provided on the body wherein the apertures in each set are axially and/or radially displaced from each other.

15. A connector according to any of the preceding claims wherein the locking bolts are shear bolts which shear at a specified torque and the conductor end is the end of a core of an electric cable.

16. A connector according to claim 15 wherein the locking bolts are drivable by a tool which ensures the location of the plane of shear of the same relative to the connector.

17. A method for the connection of two conductor ends comprising placing an end of a first conductor into a port defined in one end of an electrical connector and placing the end of the second conductor into an open channel defined in the other end of the connector, sliding a sleeve provided on the connector from a first position adjacent the open channel to a second position to substantially enclose the open channel member, and the sleeve and body are provided with apertures for the reception of locking bolts therein to secure and electrically connect the conductor ends to the connector and hence to each other.

18. A method according to claim 17 wherein there is provided an intermediate step of moving a bridge cover into position over the open channel once the conductor end is in position in the same and then moving the sleeve to the said second position.

19. A connector for the electrical connection of at least one conductor end thereto comprising a connector body with at least one open channel therein, a bridge cover and a sleeve having a longitudinal aperture, said conductor end received in the open channel and the bridge cover moved to cover the said open channel and conductor end and wherein said sleeve is resiliently movable to locate the bridge cover on the connector body by pressing the connector body through the longitudinal aperture by expanding the same in the sleeve to contact and locate on the bridge cover to hold the cover in position on the connector.

20. A connector according to claim 19 wherein the sleeve is formed from resilient sheet material such that the aperture returns to its original width following expansion.

21. A connector is hereinbefore described with reference to Figures 5A-C, and 6A-B.

21. A connector is hereinbefore described with reference to Figures 1A-D, 2A-C, 3A-C, and 4A-C.