GB2281456A

GB2281456A - Cable lead-through of electrical connector casing

Info

Publication number: GB2281456A
Application number: GB9417276A
Authority: GB
Inventors: Joerg Aschoff; Harry Fleig; Edgar Rapp; Uwe Velte; Erik Maennle
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 1993-08-31
Filing date: 1994-08-26
Publication date: 1995-03-01
Anticipated expiration: 2014-08-26
Also published as: FR2709615A1; GB2281456B; DE4329291A1; FR2709615B1; GB9417276D0; DE4329291C2

Description

2281456 ELECTRICAL CONNECTOR FOR AN ELECTRICAL UNIT The present invention

relates to an electrical connector for an electrical unit, for example a setter or a sensor.

An electrical connector for an electrical unit is known (DE-PS 34 11 456) in which a pot-shaped contact member, which can be plugged onto a housing at an end face, serves for the connection of electrical components of a rotational angle transmitter. In that case, a multicore connecting cable is led through a passage opening of an outward wall of the member into a connecting chamber of the transmitter. For the relief of tension, the cable is laid into an annular cable guide formed at the outward wall surface and retained by squeezing by means of a detent clamp pushed onto it. For the electrical connection of the electrical components, the stripped cable ends of the connecting cable are soldered to contact tags at - the housing side, whereafter the connecting chamber or the pot shaped contact member is, for sealing, filled completely by a casting mass consisting of synthetic material. The filling by casting,. however, causes appreciable production effort, since on the one hand long standing times during the setting of the casting mass prolong the production cycle and on the other hand suction devices are necessary for reasons of environmental protection in order to filter out thd components evaporating during the setting of the casting mass.

W_ - 2 - According to the present invention there is provided an electrical connector for an electrical unit, the connector comprising a member of synthetic material having an outer wall surface and an inner wall surface, the inner wall surface bounding a connecting chamber in the member, and a connecting cable which extends from the outer wall surface to the inner wall surface and into the chamber and is moulded into the material of the member between the inner wall surface and the outer wall surface.

An electrical connector embodying the invention may have the advantage that production of a connection with an electrical component of an electrical unit is possible in a simple mode and manner, wherein the connecting cable isefficiently relieved of tension and sealed off without squeezing. It is particularly advantageous that, by comparison with the prior art, filling of the connecting chamber by casting material is not necessary, so- that shortened production cycles and a lower production effort permit manufacture at favourable costs. Advantageously, checking by a simple visual check and, if desired, further treatment of the electrical connector are possible at any time. It is also of advantage that the electrical connector makes a kit mode of construction possible in the case of a mass production of units, in particular of sensors and setters, as different connecting plugs can be provided in simple manner.

It is of advantage that an unintentional disassembly may be excluded by a simple detent connection, which is not accessible.from outside, of the member and a body of an electrical unit, so that 3 operational reliability is increased. The connector is universally suitable for a large number of body shapes and is distinguished by, in particular, a capability for rapid assembly, in which case the connecting cable is protected to a large extent against the risk of kinking.

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. 1 is a partly sectioned plan view of an electrical 10 connector embodying the invention, fitted - to a rotary angle transmitter; Fig. 2 is a detail view, to enlarged scale, of an area within the chain-dotted line II of Fig. 1;.and Fig. 3 is an end view of the electrical connector and 15 rotary angle transmitter.

Referring now to the drawings there is shown in Fig. 1 an electrical connector for, in this instance, a -rotary angle transmitter 1, which can function as an electronic engine control sensor to convert the setting of a vehicle accelerator pedal to corresponding electrical signals. These signals, fed to an electronic control device, can serve for the drive control of a setting motor of a throttle device in order to regulate the performance of the engine.

The rotary angle transmitter 1 illustrated in Fig. 1 comprises a cylindrical housing 2, for example of plastics material, in which a shaft 5 is mounted to be rotatable about a longitudinal axis 4 of W' - 4 - the housing 2. The housing 2 at one end face 7 has a sleeve-shaped projection 9, into which the shaft "5 is pushed and from which it projects by a free first shaft end 11 illustrated at the left in Fig. 1. A shaft sealing ring 15, which is, for example, laid into an annular groove of the projection, and a sealing cap 14, which is pushed onto the shaft end 11 and encloses the projection, serve for sealing of the shaft 5. For actuation of the transmitter 1, the shaft end 11 has a notched cone to receive, for example, an actuating lever which is secured by a nut and serves for rotation of the shaft 5.

Mechanical components of the transmitter 1 are accommodated within the housing 2 between the end face 7 and a second shaft end 12, which lies in the interior of the housing 2 and is shown at the right in Fig. 1. Restoring springs can be provided as mechanical components which, connected with the shaft 5, exert a restoring force on an accelerator pedal connected with the transmitter 1, whilst corresponding friction discs influence the pedal force according to the pedal setting. A detailed description of the mechanical components and their functions is not provided, as this will be known to the expert, for example from DE-PS 34 11 456.

The shaft 5 has splines 17 at the shaft end 12 in order to receive an electrical component, for example a wiper 18 of a precision potentiometer 20. The wiper 18 has, for example, four brush-like metallic wiper contacts 19, which extend in axial direction and are lightly pressed against a resistance surface 23, which is provided with resistance tracks and faces the shaft end 12, of a substrate-like resistance disc 22 in order to set a certain - resistance value according to the rotational setting of the shaft-5.

The resistance disc 22 is retained' in an annular groove of a pot shaped receiving sleeve 24 and has, on a surface 25 remote from the shaft end 12, for example four contact tags 26, which are disposed in electrical contact with the resistance tracks of the resistor surf ace 23. The sleeve 24 is connected with the housing 2 and extends in axial direction, starting from the region of the shaft end 12, somewhat beyond an annular end face 31 of the housing 2 and terminates with an annular end face 27. For the installation of the disc 22, this is initially rotatably mounted by wedging under radial bias in the annular groove of the sleeve 24. By simple rotation of the disc 22, a given resistance value can be set, for example an idling resistance value of the transmitter 1, or compensation for tolerances of the potentiometer 20 can be carried out. Af ter setting the value or adjustment of the potentiometer tolerance, a permanent radial fixing of the disc 22 relative to the receiving sleeve 24 is effected by, for example, swaging, in particular hot swaging or ultrasonic swaging, of cut-outs provided at the circumference of the surface 25 of the disc 22. Since the swaging is carried out opposite the wiper 18 and the resistance surface 23 at the circumference of the disc surface 25, contamination by plastics material parts, such as droplets occurring in the hot swaging, between the wiper 18 and the resistance surface 23 is excluded. Due to the mounting of the disc 22 in the sleeve 24, an axial spacing between the wiper 18 and the disc 22 is producible with a small tolerance so that the potentiometer 20 can have a very small eccentricity.

7W 6 An annular contact member 35 of plastics material is provided for making contact with the electrical component, in this embodiment the potentiometer 20. The member 35 is placed on the open end 8 bounded by the end face 31 of the housing 2, so that the member 35 has an-annular end face 36 disposed in the interior of the housing 2 and an annular end face 37 disposed outside the housing. For sealing of the member 35, the member has a radial widening of an outward wall surface 39 in the form of a bead 44 in order to form an annular groove 41, which extends in axial direction from the end face 36 to about the disc surface 25 and in which a sealing ring 50, for example an O-ring, is located. During mounting of the member 35, the sealing ring 50 is pressed against the end face 31 of the housigg 2 and covers this, so that an inner annular surface 42 of the groove 41 extends in axial direction by way of an inner annular surface 51 of the sealing ring 50 into the housing 2 and partially lies against an inner casing surface 32 of the housing 2. In addition, an outer annular surface 43, which is provided at the bead 44, of the groove 41 extends about to the end face 31 of the housing 2. The outer groove surface 43 surrounds an outer annular surface 52 of the sealing ring 50 at a radial spacing thereby to form a free intermediate space which permits elastic deformation of the sealing ring 50 during the pressing of the member 35 into position.

The contact tags 26 of the potentiometer 20 are electrically connected with a connecting plug 65, which is arranged outside the housing 2, of the transmitter 1 by way of a connecting cable 60 having, for example, several cores. As is evident from the Fig. 3, 7 - the cable 60 has, for example, four individual strands 62 of insulated wire, which are sheathed' by an outer casing 61. The strands 62 project out of an inward wall surface 38, which in the illustrated embodiment is cylindrical, of the member 35 and into a connecting chamber 56, which is surrounded by the inward wall surface 38, of the member. When the member is placed on the housing end 8, the resistance disc 22 bounds the connecting chamber 56 at the housing side and the contact tags 26 project into the chamber.

For relief of tension and guidance of the cable 60, the r 35 has a lug-shaped moulded-on portion 40 of its outward wall 39, which - starting from a circularly arcuate portion of this wall - extends transversely to the longitudinal axis 4 and narrows radially outwards to define a sleeve-shaped end 70. The portion 40 is constructed approximately in T-shape. The cable 60 is embedded in the constituent plastics material of the portion 40 so that an efficient relief of tension and sealing is provided.

Advantageously, the casing 61 of the cable extends from the sleeve shaped end 70 to about halfway between the inward wall surface 38 and the free end of the portion 40. The casing 61 is removed from this halfway point to the ends of the strands 62, so that the strands are completely embedded in the plastics material as far as the inward wall surface 38 and then project individually out from that surf ace. After the member 35 has been placed on the open housing end 6, the strands 62 can be soldered at stripped ends thereof to the contact tags 26 in the connecting chamber 56.

8 - During production of the member 35, one end of the cable 60 is laid, by its outer casing 61 and the individual insulated strands 62, into an injection-moulding mould, whereafter the member 25 is moulded in plastics material in the mould. Advantageously, the connecting plug 64 can also be molded onto the cable in a second or in a common injection-moulding mould during the production of the member 35. Different plugs 65 with, for example, an identically structured member 35 are producible by different inject-ion -moulding moulds, so that setters and sensors can be produced in kit fonn at favourable costs.

For fastening of the member 35 to the housing 2 the former can be provided with, for example, three resilient fastening lugs 73, which -extend parallel to the longitudinal axis 4 from the end face 36 at the housing side to about the shaft end 12 when the member 35 is placed on the housing and have at their free ends arrow-shaped detent heads 74, which each point outwardly and have a slide surface extending parallel to the axis 4 and detent surface 76 oriented transversely thereto. During the mounting of the member 35, each detent head 74 slides in axial direction by the slide surface 75 under radial bias along the inner casing surface 32 of the housing 2 in order to detent in a longitudinal groove 81, which is machined into the inner casing surface 32 of the housing 2 and extends partially in axial direction. In that case the detent surface 76 bears against an end surface 80 at the end of the groove 81. The grooves 80, for example three in number, are arranged concentrically to the longitudinal axis 4andthe angular spacing of about 12W at the circumference of the housing. The fastening lugs 73 are correspondingly arranged at the circumference of the member 35.

The connecting chamber 56 or the member 35 is sealingly closed off after a simple visual check of the electrical contact-making between the contact tags 26 and the strands 62. Serving for this purpose is a closure lid 85, which is placed onto the member 35 and in the-installed state lies by its outer end surface 96 in alignment with the end surface 37 of the member 35. For the reception and sealing of the closure lid 85, an annular web 91 is provided at the inward wall surface 38 in the intermediate space between the end surface 27 of the contact sleeve 24 and the end surf ace 37 of the member 35. The web 91, which is shown to an enlarged scale in Fig.

2, has a radial surface 92, which faces the shaft end 12 and reduces the radius of the inward wall surface 38, and an annular sealing surface 87 facing the lid 85. The sealing surface 87 enlarges the radius of the inward wall surface 38 so that a second sealing ring 86, pressed at its annular end surfaces, bears against the sealing surface 87 and against an inward surface 95, which faces the housing 2, of the closure lid 85.

For fastening of the lid 85, this has, for example, three elastically resilient fastening lugs 88, which are formed similarly to the lugs 73 of the member 35, project axially out from the inner end surface 95 of the lid 85 and are arranged at an angular spacing of about 12C in circumferential direction. At their ends facing the second shaft end 12, the lugs 88 have arrow-shaped detent heads 89, which each point outwardly and - during plugging-on of the lid 85 - slide by an axially oriented slide surface 93 along an axial web surface 94, which is disposed between the surfaces 92 and 87 and reduces the radius of the member 35, in order to detent at the surface 92 by a detent surface 90 extending transversely to the axis 4.

- 10 W

Claims

CLAIMS il 1. An electrical connector for an electrical unit, the connector

' comprising a member of synthetic material having an outer wall surface-and an inner wall surface, the inner wall surface bounding a connecting chamber in the member, and a connecting cable which extends from the outer wall surface to the inner wall surface and into the chamber and is moulded into the material of the member between the inner wall surface and the outer wall surface.

2. A connector as claimed in claim 1, wherein at least one individual insulated strand of the cable projects from the inner wall surface of the member and into the chamber.

3. A connector as claimed in claim 1, wherein the cable comprises an outer casing extending in the member and has at least individual insulated strand moulded around by the material of the member.

4. A connector as claimed in claim 3, wherein the member is provided at its outer wall surface with an integral projection and the cable is moulded into the projection.

5. A connector as claimed in any one of the preceding claims, wherein the member is annular in shape.

6. A connector as claimed in any one of the preceding claims, wherein the member is provided with fastening lugs extending from an end face thereof.

-W 7. A connector as claimed in any one of the preceding claims, wherein the member has an encircling bead bounding an annular groove for a sealing ring.

8. A connector as claimed in claim 1, wherein the member is closed at one end thereof by a closure cover element plugged into position.

9. A connector as claimed in claim 8, wherein the cover element has fastening lugs detented at an annular surface portion of the member.

10. A connector as claimed in claim 6 or claim 9, comprising three such fastening lugs disposed at an angular spacing of substantially 1200.

11. A connector substantially as hereinbefore described with reference to the accompanying drawings.

12. An electrical unit comprising a body containing an electrical component and a connector as claimed in any one of the preceding claims fastened to the body, the cable being electrically connected to the component. 13. A unit as claimed in claim 12, wherein the connector is claimed 20 in claim 6 and the fastening lugs are engaged in a recess or recesses in the body.

12 14. A unit as claimed in claim 12 or claim 13, wherein the unit is a setter or a sensor.

15. An electrical unit substantially as hereinbefore described with reference to the accompanying drawings.

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