GB2151860A

GB2151860A - Pin-gripping electrical socket contact

Info

Publication number: GB2151860A
Application number: GB08430120A
Authority: GB
Inventors: Gianpiero Guzzeloni
Original assignee: Individual
Current assignee: Individual
Priority date: 1983-12-20
Filing date: 1984-11-29
Publication date: 1985-07-24
Also published as: DE3445152C2; GB8430120D0; BR8406520A; IT1210048B; IT8342923A0; FR2556889A1; DE3445152A1; FR2556889B1; GB2151860B

Abstract

An electrical connector comprises a U-shaped bent plate provided with an opening to receive a contact pin and with tongues (33, 35) to grip an electrical lead (33, 35). The plate is also provided with two part-conical recesses so arranged as to axially envelope the pin when inserted through the opening. <IMAGE>

Description

SPECIFICATION Electrical connector The present invention relates to an electrical con nector, especially a connector utilizable in conjunc tion with an electric motor such as a hermetically sealed electric motor.

Such a motor may be hermetically sealed in a casing with a set of pins extending from the out side of the inside of the casing for coupling with a corresponding number of electric connectors in or der to supply current for the motor. Each connec tor comprises a first portion for connection with a cable from the motor and a second portion for connection with one of the pins, which is con nected to a current supply source.

At present, at least two principal types of con nectors are known. One type is characterised by I the fact that the coupling with the pin is obtained by embracing the pin by a tongue, which makes the connector reliable but very expensive because of the material cost and the complexity of bringing about the connection. The other type is character ised by the fact that its coupling with the pin is ob tained in a U-shaped tongue with its two larger sides parallel and with sizes little smaller than that of the pin, so that when they are connected the two sides resiliently engage the pin.This latter type of connector, even if it is easy to construct and cheap, is not always satisfactory for repeated connections of the pins and, moreover, as the elec trical contact takes place only at a point any loss in resilience due to repeated vibration in unfavoura ble conditions (for example temperature variations) may lead to a break of the pin-connector coupling.

Such a drawback is most serious in the case of connectors employed in conjunction with hermeti cally sealed motors, for example for refrigeration compressors, because disruption of electrical con tact may lead to failure of the motor and thus of the compressor.

It would thus be desirable to overcome the above-described drawbacks by way of an electrical connector of low material requirement and simple application and which ensures contact with the pin in a durable manner.

According to a first aspect of the present inven tion there is provided an electrical connector com- prising a plate bent to be of U-shaped cross section, portions of the arms of the U-shape being formed as tongues bendable to grip an electrical lead to be electrically connected to the connector and the plate being provided with an opening to enable insertion of an electrical contact pin be tween the arms and with means to axially enve lope an inserted pin.

According to a second aspect of the present in vention there is provided a sealed motor unit com- prising a casing, an electric motor hermetically sealed in the casing, and an electrical coupling ar ranged in the wall of the casing and comprising a plurality of connectors each according to the first aspect of the invention, each of the connectors being connected by an electrical lead to the motor and being so arranged that said opening is positioned for reception of an electrical contact pin inserted from externally of the casing.

According to a third aspect of the invention there is provided a blank for formation of a connector according to the first aspect of the invention, the blank comprising a plate having a central portion and two outlying portions bendable relative to the central portion to form a U-shape, the central portion being provided with an opening and each of the two outlying portions being in part shaped as a tongue and being provided with a recess adjoining the opening at a respective one of two opposite sides thereof.

An embodiment of the present invention will now be more particularly described by way of example with reference to the accompanying drawings, in which: Fig. t is a view of part of a sealed motor unit incorporating an electrical coupling with connectors embodying the present invention; Fig. 2 is a perspective view of the connector with connected electrical lead; Fig. 3 is a cross-section of the coupling in Fig. 1 showing the location of the connector of Fig. 2; Fig. 4 is a plan view of a blank for formation of the connector of Fig. 2; Fig. 5 is a side view of the connector; Fig. 6 is a plan view of part of the connector; and Fig. 7 is a sectional view of part of the connector, showing a pin connected thereto.

Referring now to the drawings, there is shown in Fig. 1 part of a sealed motor unit comprising a casing 10 in which is hermetically sealed a motor compressor which includes an electric motor 12 supported by a support block 14. Mounted in the casing is an electrical coupling comprising pins 16 which extend from the outside to the inside of the casing for the supply of current to the motor 12 and which are connected to individual connectors 22 (Figs. 2 and 3) in a housing 18. The housing 18 has cavities 20 receiving the connectors 22. A flexible tongue 24 keeps each connector 22 in position when inserted into the respective cavity 20 and the housing is provided to the wall opposite to the tongues 24 with holes 26 to receive the pins 16.

Each connector 22 (Figs. 2 to 7) is formed by a plate 31 in which tongues 33 and 35 and an opening 37 are cut. Formed in the plate 31, at opposite sides of the opening 37, are two symmetrical partconical recesses 39, the function of which will be later explained.

After forming of the opening 37, tongues 33 and 35 and recesses 39, the plate is bent along axes 40 and 41 (Fig. 4) in such a way as to impart a Ushaped cross-section to the plate.

After bending of the plate 31, the tongues 33 and 35 can be bent to engage an electrical wire 42 (Figs. 2 and 3) and its insulating sheath 44 respectively, so that a secure contact between the wire 42 and the connector 22 is obtained. When the plate 31 is bent into U-shape, the recesses 39 assume a vertical position and form two part-cones with the opening 37 as a common base. Such an arrange ment of the recesses causes the pin 16, when inserted through the hole 26 in the housing 18 and the opening 37 in the connector, to move towards the vertex of a notional cone defined by the recesses 39. In such a way, because the upper end of this cone has a smaller diameter with reference to that of the pin 16, the pin presses the ends of the recesses 39 causing the side walls of the plate 31 to rotate outwards about the axes 40 and 41. This rotation has the effect that the inner walls of the recesses 39 envelop the pin 16 axially so as to ensure a secure contact between the connector 22 and the pin 16.

When the pin is disconnected from the connector 22, the plate 31 returns resiliently in the position of Fig. 5.

On pushing of the pin 16 completely into the connector 22 the conic conformation of the recesses 39 causes a secure contact to always be obtained even after several pin-connector couplings during the mounting phase of the motor-compressor. This contact security withstands even the vibrations which load the connector during the working of the motor-compressor when installed in, for example, refrigerating apparatus.

Claims

1. An electrical connector comprising a plate bent to be of U-shaped cross-section, portions of the arms of the U-shape being formed as tongues bendable to grip an electrical lead to be electrically connected to the connector and the plate being provided with an opening to enable insertion of an electrical contact pin between the arms and with means to axially envelope an inserted pin.

2. A connector as claimed in claim 1, said means comprising two mutually facing part-conical recesses arranged one in each arm with the base of each cone adjoining said opening.

3. A connector as claimed in claim 2, wherein those ends of the two recesses that are remote from the opening lie on a circle having a diameter smaller than a given diameter of such pin thereby to cause the arms to be bent away from each other on insertion of the pin through the opening and along the recesses to between said ends thereof.

4. An electrical connector substantially as hereinbefore described with reference to the accompanying drawings.

5. A sealed motor unit comprising a casing, an electric motor hermetically sealed in the casing, and an electrical coupling arranged in the wall of the casing and comprising a plurality of connectors as claimed in any one of the preceding claims, each of the connectors being connected by an electrical lead to the motor and being so arranged that said opening is positioned for reception of an electrical contact pin inserted from externally of the casing.

6. A sealed motor unit substantially as hereinbefore described with refernce to the accompanying drawings.

7. A blank for formation of an electrical connector as claimed in claim 1, comprising a plate having a central portion and two outlying portions bendable relative to the central portion to form a U-shape, the central portion being provided with an opening and each of the two outlying portions being in part shaped as a tongue and being provided with a recess adjoining the opening at a respective one of two opposite sides thereof.

8. A blank as claimed in claim 7, wherein each of the recesses is part-conical and adjoins the opening at the base of the cone.

9. A blank substantially as hereinbefore described with reference to and as illustrated by Fig.

4 of the accompanying drawings.