US2998588A - Two-part electrical connectors - Google Patents

Description

2 Sheets-Sheet 1 Filed Aug. 10, 1959 luv- g- 29, 1961 J. J. CHAMBERLAIN 2,998,588

TWO-PART ELECTRICAL CONNECTORS Filed Aug. 10, 1959 2 Sheets-Sheet 2 UNLOCKED 12km." UWWQIMW United States Patent 2,998,588 TWO-PART ELECTRICAL CONNECTORS John Joseph Chamberlain, Benington, England, assignor to The English Electric Company, Limited, London, England, a British company Filed Aug. 10, 1959, Ser. No. 832,774 6 Claims. (Cl. 339-7 This invention relates to two-part electrical connectors.

The invention essentially consists in a twopart electrical connector having at least one contact pin and cooperating resilient contact sleeve, and provided with a clamping member through an aperture in which the contact sleeve passes at least when the two parts of the connector are in engagement, the walls of the aperture acting on movement of the clamping member from a released to a clamped position to deform the contact sleeve to cause it to grip the contact pin.

Although the invention may be applied to connectors having only a single pin and sleeve contact pair, it is more particularly applicable to multi-point connectors, such as may be used for the interconnection of electronic or communication apparatus, in which it is desired to combine consistently good electrical contact between the pins and the sleeves with ease of separation and engagement of the two parts of the connector. In such a construction the clamping member will of course be common to all the contact pairs, each contact sleeve passing through a separate aperture in the clamping member.

Other features of the invention will be evident in the following description of various forms of electrical connectors embodying preferred forms of the invention. The description refers to the accompanying drawings, in which:

FIG. 1 is a side elevation, partly sectioned, of a multipoint two-part connector;

FIG. 2 is a transverse cross-section of the connector shown in FIG. 1 on the line marked 2P-2 in that figure;

FIGS. 3a and 3b show respectively a plan and a crosssection of part of a clamping member included in the construction of FIG. 1;

FIG. 4 shows details of the mating contact parts of the connector;

FIG. 5 is an external view of the complete connector; and

FIG. 6 shows a cross-section through the mating contact parts of a fiurther form of connector.

The general arrangement of the connector shown in FIGS. 1-5 of the drawings will be evident from a consideration of FIGS. 1 and 2. The two parts of the connector, which may be distinguished as the plug part 10 and the socket part 11, each consist of a composite body member 12 carrying the contact members, an outer casing formed by a cable sleeve 13 for receiving the incoming cables to the connector, and a retaining ring 14 by means of which the body 12- is clamped against an end face of the cable sleeve 13. The two parts of the connector are circular in cross-section, the retaining ring 14 being screwed on to the cable sleeve 13. Threaded studs 15 pass throughthe retaining ring 14 and bear against the wall of the cable sleeve 13 to prevent relative rotation of these parts. Further threaded studs 16 prevent relative rotation of the body member 12 and the retaining ring 14.

Each of the body members 12 comprises two discs 12a and 12b of moulded insulating material with a resilient sealing disc 17 compressed between them. A series of holes, with their centres disposed on three circles co-axial with the connector, are provided in these components for the plug contacts 18 or socket contacts 19 of the connector. Each hole in the outer plate 12a of the body member is counterbored to provide a location for a shoulder 20 formed on the contact. With this construction, damaged contacts may be very easily replaced, while the seal 17 prevents the ingress of moisture to the interior of the connector part through the apertures in the body members.

The body members 12 may, of course, be moulded each from a single piece of insulating material, the contacts being permanently inserted within the body member during the moulding process.

The exposed parts of the plug contact members 18 form contact pins 21, and those of the socket contact members 19 form sleeve contacts 22; these parts will be described in more detail with reference to FIG. 4, it being sufii-cient here to mention that the contact pin 21 is a solid pin while the sleeve 22 is sufficiently thin to be resilient and readily deformable.

A generally circular clamping plate 23 is pivotally secured to the socket part 11 of the connector by means of a screw 24, both the plate 23 and the screw 24 being moulded in insulating material. The clamping plate has formed in it a series of slots 25, one for each cooperating contact pair of the connector. The slots 25 are arcua-te in form, their side walls being formed by I arcs of constant angular length having their centres on the axis of the connector; one end of each slot is closed by a semicircular portion having the same diameter as the separation of the arcuate slot Walls, while the other end of the slot is closed by a part-circular portion of rather greater diameter. This slot formation does not extend for the full depth of the clamping plate 23, the slots 25 being widened as shown at 26 where they open on to the inner face of the clamping plate 23 to provide a clearance for the contacts. The formation of each of the slots 25 is shown in plan and in cross-section in FIGS. 3a and 3b respectively.

Since, as will be clear from FIG. 2, the formation of the slots 25 in the clamping plate repeats the formation of the connector contact members, movement of the clamping plate 23 about its central pivot through an angle of about 10 degrees will cause each contact sleeve 22 to move from one end to the other of the associated slot 25. In the released position of the clamping plate 23, each sleeve contact 22 lies in the enlarged end portion 25a of its associated slot, the diameter of this end portion being such as to allow a slight clearance around the contact sleeve and thus to permit the ready insertion or removal of the associated contact pin 21. When the clamping plate 23 is moved to its clamped position, the arcuate side walls of the narrower portion of the slot, which are separated by a distance slightly less than the normal diameter of the contact sleeve 22, deform the cont act sleeve to cause it to grip the contact pin. Since the contact sleeves lie at the extreme end of the narrower portion of the slot 25, between parallel parts of the slot walls, when the clamping plate 23 has completed its movement to its clamped position, there is no tendency for the clamping plate to return of its own accord to its released position.

The locking action of the clamping plate 23 is assisted by the formation of the contact pins 21 and sleeves 22. An enlarged view of these components is shown in FIG. 4 of the drawings on a larger scale. The contact members are here shown side by side but in the same relative position as in their normal engaged position.

The contact pin 21 is a solid copper pin of circular cross-section, having -a tip portion 27 of constant diameter and a reverse-tapered portion 28 between the tip 27 and the pin root. The sleeve contact 22 is a thin-walled copper sleeve having a pair of diametrically opposed slots 29 running longitudinally from its open end and terminating each in a circular hole 30. As will be seen from FIG. 4, the bottom of each cut 29, formed by the hole 30, is situated when the contact pin and sleeve are in normal engagement at a point well down the constant diameter tip portion 27 of the contact pin. Comparison with FIG. 1 shows that the action of the clamping plate 23 in deforming the contact sleeve 22 consists in bending the upper part of the contact sleeve over the shoulder formed in the contact pin 21 by the conjunction of its constant diameter tip portion 27 and its reverse-tapered portion 28. A positive locking etfect is thus achieved.

It will be evident that in addition to its locking function the clamping plate 23 also provides protection for the contact members against inadvertent damage, and particularly protects the thin-walled sleeve contacts 22 against damage when the two parts of the connector are separated. Seals to prevent the ingress of moisture into the space between the body members 12 and the clamping member 23 when the parts of the connector are engaged, are formed by walls 31 of part-circular cross-section. projecting from the face of each body member 12 and completely surrounding the contact area; these walls bear against the adjacent face of the clamping plate 23 to provide a seal. It will be noted that, except for its central boss. which receives the securing screw 24, the face of the clamping plate 23 adjacent to the socket part of the connector is relieved to provide a clearance.

In many applications, it is necessary to provide a mechanical retaining device between the two halves of the connector in addition to that provided by the contact clamping means; for example safety regulations for a particular application may specify that a mechanical retaining device between the halves of the connector should be completely independent of the electrical connections. The connector shown in the drawings is therefore provided with a bayonet-union type retaining device, shown in the general view which forms FIG. 5. A bayonet locking sleeve 32 can revolve about the plug part of the connector, to which it is secured, its skirt projecting beyond the plug part 10 to receive the socket part 11. Four axial slots 33, and corresponding circumferential slots 34, leading out of them, co-operate with the heads of the studs (which lock the body retaining ring 14 of the socket part 11 to its cable sleeve 13) to lock the two parts of the connector together. The axis slots 33 in the locking sleeve extend beyond the corresponding circumferential slots 34 for approximately half the length of the sleeve to receive four corresponding studs 35 projecting radially from the circumference of the clamping plate 23, of which they form integral parts.

The angular motion of the locking sleeve 32 necessary to cause the co-operating studs 15 to pass from the axial slots 33 to their engaged positions at the end of the circumferential slots 34 thus also moves the clamping plate 23 from its released to its clamped position. A single movement of the locking sleeve 32 thus mechanically locks the two parts of the connector together by virtue of the bayonet-union type retaining device it embodies, and also effects the individual clamping of each co-opcrating contact pair of the connector through the medium of the clamping plate 23. The simultaneous release of the contacts and of the bayonet union is efiected in the same way.

On engagement of the two parts of the connector, the bayonet locking sleeve 32, which is free to rotate on the plug part 10 of the connector, is placed over the socket part 11 with the clamping plate studs 35 passing up its axial slots 33; the engagement of these slots with the co-operating studs 15 on further engagement of the parts ensures that the clamping plate 23 is in its released position before engagement of the contact pins and sleeves occurs. It will be seen from FIG. 2 that a completely symmetrical disposition of the contacts is employed, correct location of the two body members 12 of the connector prior to engagement of the contact pins and sleeves being ensured by a pair of locating tabs 36, of different sizes, extending from one connector part to enter corresponding recesses formed in the other part. Engagement of the contact pins and sleeves presents no difficulty, since the clearance afforded by the enlarged ends 25a of the locking slots in the clamping plate 23 permits slight movement of the contact sleeves to accommodate the pins.

In a modified version of this connector, the composite construction of the two parts of the connector, involving the assembly of a number of component parts and also involving the use of such devices as moisture seals and cable anchorages, is abandoned in favour of a one piece moulded construction for each part of the connector; each connector part then comprising a solid block of moulded insulating material in which the plug or socket contact members are embedded together with the conductors connected to them. In a construction similar to that shown in the drawings, for example, the clamping plate 23 and the bayonet locking sleeve 32 would be the only removable parts of the connector.

Although the connector shown in the drawings is employed for connecting together the free ends of a pair of multi-core cables, it is evidently equally suitable for connecting such a cable to a piece of apparatus, one part of the connector being then provided with a flange for receiving it to the apparatus.

FIG. 6 of the drawings shows a cross-section through the mating contact pairs of a further form of connector, in which a contact clamping plate is again arranged for limited movement in a direction normal to the axes of the co-operating contact pins and sleeves 81 to effect its clamping and unclamping action. In this version of the connector, however, the clamping plate 80 is arranged for limited rectilinear movement, being a rectangular plate slidably mounted within a rectangular body member 82 of one part of the connector. The pins and sleeves 81 are arranged in three similar rows and the corresponding tapered slots 83 formed in the plate 80 for each contact pair communicate with each other to form three irregular slots running along the length of the plate 80. The plate is slightly longer than the corresponding dimension of the body member 82, so that in either operative position it projects at one side of the body member.

As in the versions previously described, the clamping plate 80 may be arranged to co-operate with, or to form part of, a mechanical locking means for the two parts of the connector.

What I claim as my invention and desire to secure by Letters Patent is:

1. An electrical connector comprising a first connector part having at least one contact pin having a tip portion and a second portion of reduced thickness compared with the tip portion, a second connector part having at least one corresponding hollow contact sleeve engaging over the contact pin and being slotted and inwardly-deformable at least over that portion engaging the reducedthickness portion of the pin, a clamping member formed with at least one slot having an enlarged portion of a dimension greater than the free dimension of the slotted portion of said sleeve and a narrower portion of a dimension less than said free dimension, said clamping mem her being movable transversely of said pin and sleeve between a released position in which the inwardlydeformable portion of the sleeve co-operates with the enlarged portion of the slot and a clamped position in which the inwardly-deformable portion of the sleeve lies within the narrower portion of the slot thereby to be deformed inwardly to grip the reduced-thickness portion of the pin.

2. An electrical connector as claimed in claim 1 comprising pivotal mounting means whereby the clamping member is pivotally mounted on one connector part for angular movement between its released and clamped" positions.

3. An electrical connector as claimed in claim 2 comprising a slotted locking sleeve rotatably mounted on one connector part, projections on the other connector part co-operating with said locking sleeve, and an operative connection between the locking sleeve and the clamping member, at least when the connector parts are engaged, whereby rotation of the locking sleeve rotates the clamping member between its released and clamped" positions.

4. An electrical connector comprising a first connector part having a plurality of aligned contact pins, each pin having a tip portion and a second portion of reduced thickness compared with the tip portion, a second connector part having a plurality of corresponding aligned hollow contact sleeves each sleeve engaging over a contact pin and each sleeve being slotted at least over that portion engaging the reduced-thickness portion of the pin, a clamping member formed with a plurality of slots, each slot having an enlarged portion of a dimension greater than the free dimension of the slotted portion of said sleeve and a narrower portion of a dimension less than said free dimension, said clamping member being movable transversely of said pins and sleeves between a released position in which the slotted portion of the sleeve co-operates with the enlarged portion of the slot and a clamped position in which the slotted portion of the sleevelies within the narrower portion of the slot thereby to be deformed inwardly to grip the reduced-thickness portion of the pin.

5. An electrical connector as claimed in claim 4 comprising pivotal mounting means whereby the clamping member is pivotally mounted on one connector part for angular movement between its released and clamped positions.

6. An electrical connector as claimed in claim 5 comprising a slotted locking sleeve rotatably mounted on one connector part, projections on the other connector part co-operating with said locking sleeve, and an operative connection between the locking sleeve and the clamping member, at least when the connector parts are engaged, whereby rotation of the locking sleeve rotates the clamping member between its released and clamped posi tions.

References Cited in the file of this patent UNITED STATES PATENTS

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