WO2011121271A1

WO2011121271A1 - Electrical connection

Info

Publication number: WO2011121271A1
Application number: PCT/GB2011/000371
Authority: WO
Inventors: Raymond Wild
Original assignee: Raymond Wild
Priority date: 2010-03-30
Filing date: 2011-03-17
Publication date: 2011-10-06
Also published as: GB201005392D0; GB2479163A

Abstract

A method for quickly connecting together, without the use of tools, two or more bared electric wires or for connecting one or more bared wires to a terminal. The method uses a conductive strap (3) which is deformed by a forming element (6) in order that it be clamped onto and partially wrapped around the wire or wires (5) to make the electrical connection. The method permits any number of wires, up to a maximum, to be connected and enables wires of different sizes and different types to be connected, when required.

Description

Electrical connection

The invention relates to electrical connections, specifically the connection of electrical wires and the connection of wires to terminals

A common method for connecting electrical wires requires that the bared ends of the two or more wires to be connected be placed in a hole in a terminal and clamped together by means of a screw which bears on the wires. The same method is often used to connect a wire to a fixed conducting electrical terminal or pin, for example in an electrical plug. This method is a form of clamping. It allows for the use of solid and multi-strand wires. This method of connection allows for the connection to be dismantled and remade but it suffers from several disadvantages. It requires the use of a tool - typically a screwdriver - to make the connection, which may be a relatively time consuming process. The connection may be, or may become, loose if not properly made or as a result of vibration. The size of the hole may limit the number and/or size of the wires that can be

accommodated. Because of the number of components and the number of manufacturing operations required, it is a relatively complex and expensive means for fulfilling the function.

As an alternative to the use of a screw for the connection of a wire to a terminal or pin, several proposals have been made for a means to provide a connection by placing a bared wire in a hole and distorting a part of the terminal in such a way as to trap the wire in position. UK Patent application GB 2173361 describes such a method, in which the pin is distorted, whilst application GB 2004707 describes a method in which part of the pin is partially sheared in order to clamp the wire. Patent Application GB 2279821 describes a method involving the combination of distortion and shear. Such methods are appropriate for the permanent connection of wires to conducting terminals. They do, however, suffer some disadvantages. Because of the precision required in the process of distortion or shear it normally necessitates the use of a single wire of a predetermined size, as the hole in the pin or terminal is intended to accommodate a particular wire size only. Further, the use of multi-strand wires is not normally possible as the method of making the connection can cause some of the separate strands to be severed. The method also requires the use of special tools such as a punch or press to distort or shear the terminal.

Other clamping methods, in addition to those referred to above, can also be used for connecting wires together and for connecting wires to a terminal. Typically the wires to be connected together are laid side by side within a conductive component. A tool is then used to press the component onto the wires in such a way as to distort, or crimp it and the wires and thus make a connection. The same method can be used to connect a wire to a terminal or to terminate a wire such that it can then be connected by some other means to a terminal. Patent application GB 2008/050789 describes such a method in which a sleeve type component clamps onto the wire and also partly cuts into those wires. A special tool is required for clamping wires in this way and usually each application is intended for a particular, predetermined size of wire. Nonnally two wires are connected together in this way or one wire is terminated. US 3,437,979 describes a different method of making connections by clamping. Here a pair of wire clamping jaws are used. They form two levers hinged together such that the jaws may be opened to receive the wires, and brought together to clamp the wires. This approach has the benefit of not needing special tools to make the connection. Moreover the connection may be dismantled and remade. However, in order to make a secure connection the jaws will be intended only for a specific size and number of wires.

Another method used for connecting wires and for connecting a wire to a terminal involves the use of a 'V shaped slot in a conductive component. The sides of the slot are sharp or serrated such that when the wire is pushed into the slot these edges penetrate the conducing wire and thus make an electrical connection. If appropriate, such connection is made without the need to bare the ends of the wire as the 'V shaped component may also cut through the insulation. Patent application 11992471 describes a coupler which employs such an approach. Whilst a single 'V component connected to a terminal can be used to connect a wire to that terminal, to make an electrical connection between wires using this method will normally require the use of two 'V components which are interconnected. The principal reason for this is that it is not normally possible to secure more than one wire in the component. Moreover

the ^¾ V component will normally be designed to accommodate one predetermined size of solid wire. It is inappropriate for the use of multi strand wires as some of the strands could be severed in the connecting process.

A wrapping method is also available in which the wire to be connected is wrapped in a coil like manner around a conductive terminal or pin. Whilst two wires might be connected in this way it is more difficult to ensure a good wrapped connection, hence the method is normally used for connecting a single wire to a fixed pin. This method requires the use of a wrapping tool which in turn may make the connection of wires in this way relatively time consuming . The method is more appropriate for use with solid wires which have greater rigidity than multi-strand wire and thus make a better connection. As the wrapped connection requires several twists of the wire around the pin, the resulting connection may be relatively large.

A method of connecting by twisting a component onto wires or the wires into a component provides a similar approach. Patent application US 2008121409 deploys a moulded twist-on cap. It would be possible to make a connection between wires by applying the twisting component to two or more wires. However this approach may not ensure as secure a connection as other methods and may be appropriate only for predetermined wire sizes and types. US 2004067696 also offers a twisting method of connection - using a pair of threaded components each of which carry a wire and are screwed together. This is likely to provide a more secure connection but can only be used for predetermined wire sizes and types.

Push fit connections are also available. Typically these involve the pushing of a wire into a component which has some internal means, such as teeth, to grip the wire. Patent application WO 2008051354 offers such a method. It relies on the wire being pushed into a hole in a component to be held there by friction. Such methods might be appropriate for making a connection involving a single wire of a predetermined size, as the grip on the inserted wires might be compromised if more than one wire is to be inserted. Such connections may not be very secure and the wire or wires might become loose οτ be pulled out.

It will be evident from the above that current methods for connecting electric wires and for connecting one or more wires to a terminal have several characteristics that can be disadvantageous in certain circumstances. The need for tools to make a connection may restrict the type of situation for which a method might be used. The time required to make a connection, the space required for it and the cost of making the device are also potential disadvantages of particular methods. The requirement that only a predetermined number, size and type of wire might be accommodated will substantially limit the extent to which a device using a particular method might be used. For this reason also, most existing methods do not permit the connection of a mix of wire types or sizes. With some methods the connection afforded may not be very secure and be liable to loosening.

The intention of the present invention is to provide a quick, economic and secure method of making a connecting between two or more wires and connecting one or more wires to a terminal which overcomes the above disadvantages.

According to the invention a means is provided for connecting together two or more bared electric wires or connecting one or more bared electric wires to a terminal. The method requires three elements, namely a locating element to position the wire or wires to be connected; a strap to connect the wires together, or connect the wires or wires to a terminal; and a forming element to act upon the said strap to make the connection.

The said locating element and the said strap are held in positions fixed relative to each other, the lower part of the strap being fixed and the upper part free to move. One way, but not the only way, to achieve this is by attaching both to a base component. The forming element is required to move in a predetermined manner relative to the other two elements, in such a way as to engage with and to distort the upper part of the said strap, and to form a connection between the strap and the wire or wires positioned in the locating element.

One way, but not the only way, to provide the locating element is in the form of a slot in the non conductive material of a base component. The slot will have a width sufficient to accommodate the diameter of the largest bared wire for which the connection is intended. It will have a depth sufficient to accommodate the maximum number of bared wires of the maximum diameter for which the connection is intended. At a position along the length of the slot there will be a cut-away portion for the depth of the slot, which will expose the wires located in the slot.

The strap will comprise a thin strip of conductive, ductile material. It will be positioned such that its longest dimension - its length - is perpendicular to the longitudinal axis of the locating element. Its width will be slightly less than the width of the cut-away in the locating element, and positioned parallel to the longitudinal axis of the locating element and close to one side of the slot of that element. Its thickness will be sufficient to allow bending without fracture. Its size and material composition will enable it to retain its new form when bent. In applications of the method intended for the connection of one or more wires to a terminal, the said strap will also be connected to that terminal or held in contact with it. In such applications where an intermediate component, such as a fuse, is incorporated between the wire or wires to be connected and a terminal, the strap will connect directly or via another component to the appropriate part of the intermediate component. The position of the strap relative to the locating element will enable its upper part, under the action of the forming element, to be bent over and to clamp down on the top of the uppermost wire in the locating element and to pass down the exposed side, or sides, of the wire or wires. The length of the strap will be sufficient to make contact in this manner with the maximum number of wires of the maximum diameter for which the connection is intended when fully acted upon by the forming element. Adequate space will be provided adjacent to and below the locating element to accommodate the strap when fewer wires or smaller wires than the maximum allowed are connected.

The forming element, made of a non conductive material, will move in a predetermined manner relative to the strap and locating elements. One way, but not the only way, to achieve this is through a hinge mechanism. The hinge axis may be parallel to the longitudinal axis of the locating element. The acting face of the locating element will be parallel to the width of the strap and of the wire or wires to be connected. The face will be of a similar width to that of the strap. The method of forming the connection requires that the bared wires are positioned in the locating element, the strap is then manually bent over the top wire and the forming element is then activated. The acting face of the forming element first engages with the strap and as it is moved to its final, closed, position it clamps the strap over the top wire, and for more than one wire clamps the wires together, and positions the strap along the exposed side, or sides, of the wire or wires being connected. When fully in position the forming element is held in that final, closed, position.

Specific embodiments of the invention will be described by way of examples. Each example relates to a single connection between wires, or between one or more wires and a terminal. Devices using the connection method of this invention will provide for one or more such connections. Reference is made to the accompanying drawings all of which show enlarged views and are not to scale, wherein -

Figure 1 shows a locating element 1 formed as a slot in a non conductive base component 2. The locating element provides space 4 for access to the wire or wires in the locating slot. Also shown is the strap 3 with its lower part fixed in the base and located relative to the slot.

Figure 2 shows a cross section through the strap 3 and locating slot 1.

Figure 3 is as Figure 2 but with three wires 5, being the maximum number of wires and maximum diameter for which this application is intended, positioned in the locating element

Figure 4 is a cross section through the strap, the locating slot and wires, as Figure 3, but showing also the forming mechanism 6 as a pivoted element, with the pivot axis 7 parallel to the wires, in the initial open position, relative to the wires and strap.

Figure 5 shows cross sections, for the arrangement shown in Figure 4, showing the steps involved in making the connection, namely- a. the strap is bent manually over the top wire

b. the forming element is moved to a position in which it engages with the strap

c. the forming element is moved to its final, closed, position and the strap is clamped down onto, and along the sides the wires

Figure 6 is as for Figure 5c where only two wires are to be connected

Figure 7 is a cross section as Figure 5c but showing the connection of 3 wires of different sizes, including one wire of the maximum diameter intended for this particular application.

Figure 8 is a cross section showing one wire connected to a terminal 8 which in this case is a pin fixed in and through the base 2. The strap is connected, in this case by means of a pin 9, to the terminal .

Figure 9 is a cross section as Figure 4, but showing the forming element as an integral part of a lid or cover 10 which pivots on the base 2 by means of a hinge 11.

The location of the strap is shown in all the Figures. It is shown here secured to the base in such a way as to enable it to bent over and subsequently clamped down on the top wire in the location slot, whether there be just one wire or more. The recess provided below the wires enables the strap to be accommodated when fewer than the maximum number and/or sizes of wires are used, as shown in Figures 6 and 8.

The forming element is shown here as a hinged item. The acting surface is that part which makes contact with the strap during its full movement from open to closed position. Its dimensions and the shape of its acting surface are such as to enable it to bend the strap tightly over the top wire, and to position the strap down the side of the exposed wire or wires, as shown in Figures 5, 6 and 7. One, but not the only, means to provide the forming element is to incorporate it in a lid or cover component hinged to the base, such that during closure, the forming element performs the function described, and when closed the lid is secured to the base.

Where two or more wires are to be connected together, the electrical connection is made by the strap clamping down on the top wire and thus also clamping the wires together. Secondary contact may be made between the strap and the sides of one or more of the wires. Where two or more wires are to be connected to a terminal, the connection is made in this manner and with the strap connected also to the terminal. Where one wire is to be connected to a terminal, the connection is made by the strap clamping down on the wire and the strap also being connected to the terminal.

Claims

1. A method for connecting together two or more bared electric wires, comprising; a locating element to hold in position the said wires to be connected whilst also exposing part of the said wires; an electrically conducting strap which in order to form the connection is deformed to act on the exposed part of the said wires electrically to connect the wires together and to the strap; and a forming element to act upon the said strap to deform it in such a way as to make the connection, whereby the said locating element and the lower part of said strap are held in positions fixed relative to each other with the upper part of the said strap free to be deformed, whereas the forming element is required to move in a predetermined manner relative to the wires positioned in the locating element and the said strap, in such a way as to engage with, act upon and to deform the said strap such that the said strap will clamp and hold the wires positioned in the said locating element to form an electrical connection between the strap and the wires.

2. A method for connecting one or more bared electric wires to a terminal,

comprising; a conductive terminal; a locating element to hold in position the said wire or wires to be connected whilst also exposing part of the said wire or wires; an electrically conducting strap which in order to form the connection is deformed to act on the exposed part of the said wire or wires electrically to connect the said wire to the strap, or the wires together and to the strap; and a forming element to act upon the said strap to deform it in such a way as to make the connection, whereby the said locating element and the lower part of said strap are held in positions fixed relative to each other with the upper part of the said strap free to be deformed, the strap also being electrically connected or held in such contact from its fixed part with the said terminal, whereas the forming element is required to move in a predetermined manner relative to the wire or wires positioned in the location element and the said strap, in such a way as to engage with, act upon and to deform the said strap such that the said strap will clamp and hold the wire or wires positioned in the said locating element to form an electrical connection between the strap and the wire or wires.

3. A method for connecting one or more bared electric wires to a terminal via an intermediate component, comprising; a conductive terminal; an intermediate component forming part of the electrical circuit from the wire or wires to the terminal; a locating element to hold in position the said wire or wires to be connected whilst also exposing part of the said wire or wires; an electrically conducting strap which in order to form the connection is deformed to act on the exposed part of the said wire or wires electrically to connect the wire to the strap, or the wires together and to the strap; and a forming element to act upon the said strap to deform it in such a way as to make the connection, whereby the said locating element and the lower part of said strap are held in positions fixed relative to each other with the upper part of the said strap free to be deformed, the strap also being electrically connected to or held in such contact from its fixed part to the said intermediate component and thus electrically via that component to the terminal, whereas the forming element is required to move in a

predetermined manner relative to the wire or wires positioned in the locating element and the said strap, in such a way as to engage with, act upon and to deform the said strap such that the said strap will clamp and hold the wire or wires positioned in the said locating element to form an electrical connection between the strap and the wire or wires.

4. A method as defined in Claims 1 , 2 and 3 wherein a non conductive base is

provided to which a part of the strap is fixed and in which the location element is formed as a slot positioned perpendicular to the plane of the base.

5. A method as defined in Claims 1 , 2 and 3 wherein a non conductive base is

provided to which is secured a conductive component to comprise the locating element having a slot perpendicular to the plane of the base, and to which a part of the strap is fixed.

6. A method as defined in Claims 1,2,3, 4 and 5 wherein the forming element is provided as a component hinged to the base, its hinge axis placed parallel to the longitudinal axis of the wire or wires to be connected.

7. A method as defined in Claims 1 ,2,3,4 and 5 wherein the forming element is provided as a component hinged to the base, its hinge axis placed at right angles to the longitudinal axis of the wire or wires to be connected

8. A method as defined in Claims 1 ,2,3,4 and 5 wherein the forming element is provided in such a way as to move in a direction perpendicular to the wire or wires to be connected and parallel to the slot provided for the wire or wires in the locating element

9. A method as defined in all the above Claims wherein a lid or cover is provided which when in place in a closed position engages with the base to form an enclosed space, where also the forming element is a part of the said lid

10. A method as defined in all of the above Claims wherein the strap is in the form of a conductive wire

1 1. A method as defined in Claims 1,2,3,4,5,6,7,8 and 9 wherein the strap is in the form of a thin strip of conductive material.

12. A method as defined in Claims 1,4,5,6,7,8 and 9 wherein the strap is comprised of non conductive material

13. A method as defined in all of the above Claims wherein one surface of the strap is serrated, grooved or otherwise textured such that when the strap is deformed by the forming element the said serrated, grooved or textured surface of the strap engages with a similarly serrated, grooved or textured surface on the acting surface of the forming element.

14. A method as defined in all the above Claims wherein the strap is removable and replaceable

15. A method as defined in Claims 1,2,3,4,5,6,9,10,11,12,13, and 14 in which a

locating element provides a slot the depth of which has a curved form with the centre of its radius of curvature at the hinge of a forming element which has its hinge axis parallel to the longitudinal axis of the wire or wires to be connected.