GB2461345A

GB2461345A - Connector with tapered pin and socket elements

Info

Publication number: GB2461345A
Application number: GB0812235A
Authority: GB
Inventors: John Anderson
Original assignee: Smiths Group PLC
Current assignee: Smiths Group PLC
Priority date: 2008-07-04
Filing date: 2008-07-04
Publication date: 2010-01-06
Anticipated expiration: 2028-07-04
Also published as: GB0812235D0; GB2461345B

Abstract

A connector comprises: a male pin element 60 and a female socket element 30 with a hyperboloid configuration of spring wires 50 extending along its length, wherein the pin element and socket element are both tapered (e.g. between 2 and 10 degrees) along their length. In further embodiments, the socket element has an open end a closed end 36, wherein open end has a larger diameter than the closed end. The connector may be an electrical connector and include a means for positively engaging the pin element with the socket element when fully inserted, e.g. interlocking detents on the sockets and pin components or a twisting locking ring on one component to lock on to a surface formation on the other component.

Description

S

CONNECTORS

This invention relates to connectors.

The invention is more particularly concerned with electrical connectors, especially electrical connectors for high current applications.

One form of conventional electrical connector comprises a socket with an hyperboloid arrangement of spring contact wires extending generally longitudinally of the socket. The connector is completed by a mating pin contact of cylindrical shape that is inserted in the socket to make a sliding electrical contact with the socket contact wires.

Existing hyperboloid connectors are all of a cylindrical configuration, that is, the male pin and female socket both have a constant diameter along their length when the contact wires are engaged by the pin. Connectors of this kind have been sold for many years under the HYPERTAC trade mark (HYPERTAC is a registered trade mark) by Hypertac Limited and its related companies. Such connectors can produce a very reliable contact, have a low insertion force, low and stable contact resistance and a high contact life after repeated insertions. The connectors are used primarily for low current, signal applications but can also be used for high current, power applications. EP1638 170 describes a modified form of hyperboloid connector for high current application. One problem with such connectors in high current applications is that a relatively large force is needed to insert the mating pin against the relatively high resilient forces exerted by the relatively large diameter contact wires. This leads to increased wear of the contact wires and a lower number of reliable insertion cycles than is desirable.

It is an object of the present invention to provide an alternative connector.

According to one aspect of the present invention there is provided a connector having a male pin element and a female socket element of the kind having an hyperboloid configuration of spring wires extending along its length, the pin element and socket element being tapered along their length.

According to another aspect of the present invention there is provided a connector having a male pin element and a female socket element of the kind having an hyperboloid configuration of spring wires extending along its length, the socket element having an open end and a closed end, the open end having a larger diameter than the closed end and the pin element being tapered to make contact with the socket element along its length when fully inserted.

The connector is preferably an electrical connector and the spring wires are preferably arranged to make electrical contact with the pin element. The socket is preferably tapered along the length of the spring wires with an angle between about 2° and 100, and preferably with an angle about 6°. The connector may include means positively engaging the pin element with the socket element when fully inserted.

According to a further aspect of the present invention there is provided a socket element for a connector according to the above one or other aspect of the present invention.

According to a fourth aspect of the present invention there is provided a pin element for a connector according to the above one or other aspect of the present invention.

An electrical connector for power applications will now be described, by way of example, with reference to the accompanying drawings, in which; Figure 1 is a perspective view of a conventional hyperboloid socket and pin of cylindrical shape; Figure 2 is a cross-sectional side elevation view of the connector of the present invention; and Figure 3 is a graph illustrating mating force against insertion depth for a standard hyperboloid connector and the tapered connector of the present invention.

With reference to Figure 1, a conventional hyperboloid connector has a male pin element 1 of cylindrical shape and constant diameter along its length with a rounded free end 2. The connector has a female socket 3 provided by a plurality of spring contact wires 4 attached at opposite ends to circular ring supports 5 and 6 of equal diameter. The wires 4 extend in a hyperboloid configuration along the length of the socket 3 so that they define a bore along the socket that, in its natural state has a smaller diameter midway along its length, which is less than the external diameter of the pin element 1. When the pin element 1 is inserted in the socket 3, the contact wires 4 are expanded outwardly by contact with the pin element to contact the pin element along its length so that, when fully inserted, the contact wires take up the cylindrical shape of the pin element.

With reference now to Figure 2, the socket 30 of the present invention has a machined metal outer body 31 with a generally cylindrical external shape. At its left-hand end the body 31 is drilled with an axial bore 32 arranged to receive an exposed conductor at the end of an electrical wire (not shown) by which electrical connection to the socket is made. Alternatively, a slot, tapped hole or other means could be provided for attaching a cable or busbar. A radial cross-bore 33 intersects the axial bore 32 about midway along its length and receives some means for retaining the conductor in the axial bore, such as solder or a fastener. The opposite, right-hand end of the body 31 is open and is formed with a cylindrical bore 34, which is reduced in diameter towards its left-hand end to form an annular step 35 and a reduced diameter closed end portion 36.

The main part of the bore 34 receives within it a metal support sleeve 40. The outside of the support sleeve 40 is of a substantially cylindrical shape and constant diameter apart from a central section 41 of enlarged diameter that is a close sliding fit within the bore 34.

The central section 41 spaces the left and right end regions 42 and 43 slightly from the wall of the bore 34 to form two annular clearance regions 44 and 45 respectively. The outside of the central Section 41 of the sleeve 40 and the bore 34 are both formed with annular grooves 46 and 47 that align with one another and are retained in the body by an interference fit. The left-hand end of the sleeve 40 locates against the annular step 35 in the bore 34. The inside 48 of the sleeve 40 is smooth, of circular section and is tapered along its length with the right-hand, open end being wider than the left-hand towards the closed end of the bore 34.

Typically the taper along the inside of the sleeve 40 is about 6° but this could be anywhere in the range of about 2° to 100.

The sleeve 40 supports several spring contact wires 50 extending generally longitudinally of the sleeve. Opposite ends of the wires are wrapped around respective opposite ends of the sleeve 40 and locate in the respective clearance regions 44 and 45 between the outside of the sleeve and the bore 34. The spring contact wires 50 are arranged in a hyperboloid configuration similar to that shown in Figure 1 but having an overall taper along their length. In their natural state, without a pin being inserted, they do not lie in contact against the inside surface of the sleeve 40 but are spaced from it, with the spacing being greatest midway along its length.

The male contact pin 60 of the present invention differs from previous pin elements used in hyperboloid connectors in that it is tapered along the length of its forward region 61, along the part of the pin that extends, in use, within the socket 30. The taper along the forward region 61 matches that of the socket sleeve 40, being about 6°. The left-hand, free end tip 62 of the pin 60 is slightly rounded. The pin element 60 shown has a rear region 63 of cylindrical shape and constant cross-section. The diameter of the pin is about 12mm and its insertion length is about 35mm.

It can be seen that, when the tip 62 of the pin 60 is presented up to the open end of the socket 30, there will be a relatively large clearance between tip of the pin and the socket opening so that the pin can be inserted initially into the socket with a very low insertion force. As the pin 60 is inserted further it will contact the contact wires 50 and push them outwardly towards the inside surface of the sleeve 40. Figure 3 illustrates how the insertion force varies with depth, the lower line "A" showing the connector of the present invention and the upper line "B" showing a conventional hyperboloid connector of cylindrical configuration. It can be seen that the mating force is considerably less for the present connector and that the major part of the insertion force is only required when the pin is almost fully inserted in the socket. Wear on both the contact wires and the contact pin is considerably reduced compared with conventional connectors because of the reduced forces employed. This increases the long-term performance of the connector and gives an increased life. Because the major part of the insertion force is only applied when the two parts of the connector are close to being fully mated, it ensures that correct alignment is achieved between the two parts before large forces need to be applied. This can reduce the risk of misalignment damage.

One possible problem with the tapered configuration is that effective interconnection is only made between the pin and socket when the pin is almost fully inserted whereas, by contrast, in conventional connectors, interconnection is established even when incompletely inserted. In order to ensure that full interconnection is made with the connector of the present invention, it is desirable for the socket and pin to be provided with some form of positive engagement or latching arrangement to make it apparent that full mating has been achieved and to maintain full mating. Any conventional latching arrangement could be used such as simple interlocking detents on the socket and pin components that snap into engagement, or a locking ring on one component that is twisted to lock on a surface formation on the opposite component.

The connector is particularly suitable for high current, power applications where relatively large diameter and stiff contact wires are used since the tapered arrangement enables contact wear to be reduced and contact life to be increased. The connector described above is suitable for currents of up to around 500A. The invention, however, is not confined to connectors for power applications since it could be used in signal applications. Typically, the diameter of the pin and socket could be between about 3mm and 25mm. The socket length could be anything up to around 50mm. The invention is not confined to electrical connectors but could be used with fibre optic or other connectors.

Claims

Claims 1. A connector having a male pin element and female socket element having an hyperboloid configuration of spring wires extending along its length, the pin element and socket element being tapered along their length.
2. A connector having a male pin element and a female socket element having an hyperboloid configuration of spring wires extending along its length, the socket element having an open end and closed end, the open end having a larger diameter than the closed end and the pin element being tapered to make contact with the socket element along its length when fully inserted.
3. A connector as claimed in claim 1 or claim 2 in which the connector is an electrical connector. *.S. * * * ** S S...
4. A connector as claimed in claim 3, in which the spring wires are arranged to make electrical contact with the pin element.
5. A connector as claimed in any preceding claim, in which the socket element is tapered along the length of the spring wires with an angle S..between 2° and 10°.
6. A connector as claimed in claim 5 in which the angle is about 6°.
7. A connector as claimed in any preceding claim in which the connector further includes means for positively engaging the pin element with the socket element when fully inserted.
8. A connector as claimed in claim 7, in which the means for engagement are selected from interlocking detents on the sockets and pin components, and a locking ring on one component that is twisted to lock on to a surface formation on the other component.
9. A socket element for a connector according to any preceding claim.
10. A pin element for a connector as claimed in any preceding claim.
11. A connector substantially as described and shown in figure 2.