GB2152617A

GB2152617A - Mechanical cable control with an automatic adjustment device and an electrical actuation detector

Info

Publication number: GB2152617A
Application number: GB08430092A
Authority: GB
Inventors: Jean Deligny
Original assignee: DBA SA
Current assignee: DBA SA
Priority date: 1983-12-22
Filing date: 1984-11-28
Publication date: 1985-08-07
Also published as: FR2557228B1; GB8430092D0; IT8424087A0; IT1178766B; ES8605621A1; GB2152617B; FR2557228A1; ES538960A0; IT8424087A1; DE3446938A1

Abstract

The mechanical cable control, incorporating a device for automatic adjustment (10, 8-7, 6,4) between a first portion (2) of the sheathing tube of the cable (1) and a second portion of the sheathing tube possessing a control member (8, 7) associated to the cable (1) so as to be displaced when the control is actuated, comprises an electrical line means (21,21') incorporating a pair of interacting electrical contacts (20, 20', 16) carried respectively by the control member (8, 7) and an element (4) of the locking device solid with the first portion (2) of the sheathing tube. <IMAGE>

Description

SPECIFICATION Mechanical cable control with an automatic adjustment device and an electrical actuation detector The present invention relates to mechanical controls by means of a cable sliding in a flexible sheathing tube incorporating an automatic adjustment device for compensating play, more particularly for controlling the friction clutch of a motor vehicle, of the type possessing a locking device which, when the mechanical control is actuated, selectively fixes to one another, by wedging them releasably, two successive portions of the sheathing tube which are stressed so as to move apart from one another, and which possesses a control member associated to the cable so that it can be displaced when the mechanical control is actuated.

A mechanical control of this type is described for instance in document EP-A-O 055 649 in the applicant company's name, the content of which is assumed to be included herein for reference.

Such a mechanical cable control is intended to connect an actuating member, typically a pedal, and a member to be actuated, typically the fork of a friction clutch of a motor vehicle, and offers the advantage that it allows automatic compensation of play by means of an adjustment device located at any intermediate point of the mechanical control, therefore without the need for any special adaptation at the ends of the cable or of the sheathing tube, whilst ensuring that the actuating cable remains integral over- the entire length of the mechanical control.

The object of the present invention is to propose a mechanical control of this type, which utilises the kinematics of the automatic adjustment device in order to provide an indication of the actuation of the member to be actuated by this mechanical control, without substantially modifying the general arrangement of this mechanical control and whilst preserving its characteristics of robustness and reliability.

For this purpose, according to a characteristic of the invention, the mechanical control possesses an electrical line means incorporating a pair of interacting electrical contacts carried respectively by the member controlling the automatic adjustment device and by an element of this automatic locking device solid with a first portion of the sheating tube.

More specfically, according to another characteristic of the invention, the electrical line means comprises at least one electrical line portion extending in the said first sheathingtube portion.

By means of such an arrangement, the relative displacement between the control member, capable of being driven by the cable when the latter is actuated, and the element solid with the first sheathing-tube portion, typically a sleeve forming a cam for actuating locking balls carried by a cage part of the control member, makes it possible to supply an electrical indication of the actuated or nonactuated state of the member to be actuated, without the need to provide contacts or other detection members at the level of the actuating member or the member to be actuated.

Where a mechanical clutch control is concerned, the closing of the electrical line means via the interacting contacts during a clutch release phase thus makes it possible to provide a signal capable of being processed in an electronic unit controlling ignition, injection or an automatic change in gear ratio.

Other characteristics and advantages of the present invention will emerge from the following description of embodiments given as an illustration but in no way limiting, this description being made with reference to the attached drawings in which: Figure 1 is a diagrammatic view, in partial longitudinal section, of a first embodiment of a mechanical cable control according to the invention; and Figures 2 and 3 are diagrammatic views of another embodiment of the mechanical control according to the invention, respectively showing the state of rest and the actuated state of the mechanical control.

In the following description and in the drawings, identical or similar elements bear the same reference numerals, if appropriate, with an index symbol.

The mechanical control illustrated in the drawings comprises a length of cable 1 fitted to slide axially in a flexible sheathing tube consisting of two successive separate portions 2 and 2'. The end of the first portion 2 is fitted into a central cylindrical housing 3 of a sleeve 4, through which the cable 1 passes and which has, at its end opposite the first portion 2 of the sheathing tube, a frustoconical peripheral surface 5 forming an actuating cam for wedging balls 6 carried by a cylindrical cage 7, in which the sleeve 4 is received so as to slide and which forms part of a control member 8 interacting by means of a frictional connection with the bare cable portion 1 between the two portions 2 and 2' of the sheathing tube, as described in the document EP-A-O 055 649 mentioned above.The cage 7 is itself received so as to slide in a closed chamber 9 defined in a composite housing 1 0, into a first end of which is fitted the end of the second portion 2' of the sheathing tube, the first portion 2 of the sheathing tube extending, so as to slide in a way made leak-proof by a gasket 11, through the other front end of the housing 1 0. It will easily be understood that a relative displacement between the cage 7 and the sleeve 4 results in locking by wedging (or in releasing) between this sleeve 4 and the housing 10, that is to say between the two separate portions 2 and 2' of the sheathing tube.A spacer spring 12 is arranged coaxially round the first portion 2 of the sheathing tube, between a collar 1 3 fastened to an intermediate zone of this first portion 2 of the sheathing tube and the adjacent end of the housing 10 (if appropriate, with a washer 1 4 being interposed).

According to the invention, the cage 7, typically made of insulating plastic, possesses, at its end opposite the friction piece 8, that is to say, adjacent to the end of the first portion 2 of the sheathing tube, an annular front wall, on the inner face of which is made at least one metallic electrical contact 20 capable of interacting, by coming up against it to make electrical contact, with the adjacent front face 1 6 of the sleeve 4 typically made of metal, for example steel.Connected to the contact 20 is one end, projecting from the first portion 2 of the sheathing tube, of an electrical line 21 consisting of an advantageously insulated wire extending in the thickness of the first portion 2 of the sheathing tube beyond the collar 13, in the opposite direction to the sleeve 4, and ending in a lug 22 for connection to another electrical line 23 connected to equipment on board the motor vehicle..

Typically, the sheathing tube 2, 2' comprises a plastic inner sliding tube, a helical metal winding 1 7 and a plastic peripheral covering sheath 1 8. Advantageously, the end of the first portion 2 of the sheathing tube, intended to be fitted into the housing 3 of the sleeve 4, is stripped of its peripheral covering sheath 18, thus making it possible on the one hand, to make it easier to connect the inner end of the electrical line 21 to its associated contact 20 and, on the other hand, during fitting to make suitable electrical contact between the turns of the sheathing winding 1 7 and the metal block of the sleeve 4.

Thus, in the embodiment illustrated in Fig.

1, the electrical line means, opened or closed when the contact 20 comes in contact with the front face 1 6 of the sleeve 4, comprises, in addition to the line 21, the helical metal winding 1 7 of the first portion 2 of the sheathing tube, a line portion 210 being connected, in a zone of this first sheathingtube portion 2 beyond the collar 13, to the helical winding 1 7 for the purpose of connection to another terminal of the equipment on board the vehicle.

In the embodiment of Figs. 2 and 3, the electrical line means comprises two separate line portions 21, 21' which are connected respectively to a corresponding contact 20, 20' in the cage 7 and which are provided at their opposite ends, with connecting lugs 22, 22', the latter serving for connection to a second line 23' connected to the other termi nal of the equipment on board the vehicle.

The lines 21 and 21' are advantageously embedded by being moulded over when the plastic peripheral covering sheath 1 8 is fitted round the winding 1 7.

The sequence illustrated in Figs. 2 and 3 shows clearly how the detection device of the mechanical control according to the invention is put into effect. In the rest position illustrated in Figs. 1 and 2, the connection between the two cable-tube portions, that is to say, between the housing 10 and the sleeve 4, is released, and the two portions 2, 2' of the sheathing tube are stressed by the spring 1 2 so as to move apart from one another. In this case, the sleeve 4 bears against the contacts 20, 20', maintaning contact by means of its face 1 6. The circuit formed by the lines 21 and 21' is closed. When the mechanical control is actuated, for example for a clutch release operation, a pull is exerted on the cable 1 which is displaced in the direction of the arrow F1 in the automatic adjustment device (Fig. 3).The first portion 2 of the sheathing tube is subjected, by reaction, to a displacing force in the opposite direction F2. As a result of this, the sleeve 4 is displaced in the cage 7, thus locking the connection as a result of wedging between the sleeve 4 and the housing 10, the front face 1 6 of the sleeve 4 then moving away from the contacts 20' a distance 20, e.

thereby opening the electrical circuit. When the mechanical control is released, the elements resume their position shown in Figs. 1 and 2, compensating, if appropriate, the play which has arisen in the mechanical control.

Although the present invention has been described in relation to particular embodi ments, it is not limited thereby, but on the contrary is capable of undergoing modifications and having alternative forms which will appear to a person skilled in the art. In particular, in the alternative form according to Fig. 1, contact with the sleeve 4 can be made, via the balls 6, by means of the inner metal lining of the housing 10, so that the electrical circuit is normally open at rest and closed during actuation.

Claims

CLAIMS 1. Mechanical cable control (1) sliding in a flexible sheathing tube (2, 2'), incorporating an automatic adjustment device comprising a locking device (6, 7) which, when the me chanical control is actuated, selectively fixes to one another, by wedging them releasably, two successive portions (2, 2') of the sheath ing tube which are stressed so as to move apart from one another, and which possesses a control member (8) associated to the cable (1) so that it can be displaced when the mechanical control is actuated, characterised in that it possesses an electrical lines means (21-21', 17, 210) incorporating a pair of interacting electrical contacts (20, 20'; 16) carried respectively by the control member (8, 7) and an element (4) of the locking device solid with a first portion (2) of the sheathing tube 2.Control according to Claim 1, characterised in that the electrical line means comprises at least one electrical line portion (21, 21', 17) extending in the first sheathing-tube portion (2). 3. Control according to Claim 1 or Claim 2, incorporating a locking device with wedging balls (6) carried by a cage part (7) of the control member (8), characterised in that the said element of the locking device consists of a metal sleeve (4) received in the cage part (7) and possessing, at one end,a frustoconical peripheral surface (5) forming a cam for actuating the wedging balls (6), a first contact of the said pair of contacts being formed by a front face (16) of the sleeve (4) capable of interacting withat least one second contact (20, 20') of the said pair of contacts, which is attached to an adjacent axial end wall (15) of the cage (7). 4. Control according to one of Claims 2 and 3, charactrised in that it incorporates a spacer spring (12) arranged between an intermediate zone (13) of the first sheathing-tube portion (2), coaxially with the latter, and a housing element (10) of the adjustment device solid with the second sheathing-tube portion (2'). 5. Control according to Claim 4, characterised in that the electrical line portion (21, 21', 1 7) extends in the first sheathing-tube portion (2) beyond the intermediate zone (13) of the first sheathing-tube portion (2) in the opposite direction to the housing element (10). 6. Control according to Claim 5, characterised in that the electrical line portion (21, 21', 17-210) projects outside the first sheathingtube portion (2) beyond the said intermediate zone (13) of the latter and possesses a means of connection (22, 22') to an outer electrical line (23, 23'). 7. Control according to one of Claims 3 to 6, characterised in that it incorporates two separate electrical line portions (21, 21', 17) extending in the first sheathing-tube portion (2). 8. Control according to Claim 7, characterised in that the two separate line portions (21, 21') are connected respectively to two second separate contacts (20, 20') attached to the said cage (7). 9. Control according to Claim 7, incorporating a sheathing tube provided with a helical metal winding (1 7) which is sheathed (18), characterised in that the end of the first sheathing-tube portion (2) is fitted into a housing (3) of the sleeve (4), with the metal winding (17) bared in electrical contact with the wall of the housing (3), this metal winding (17) forming one of the two electrical line portions. 10. Mechanical cable control substantially as hereinbefore described with reference to and as illustrated in, the accompanying drawings. CLAIMS Amendments to the claims have been filed, and have the following effect: Claims 1 to 10 above have been deleted or textually amended. New or textually amended claims have been filed as follows:-

1. A mechanical cable control with a cable (1) sliding in a flexible sheathing tube (2, 2'), incorporating an automatic adjustment device comprising a locking device (6, 7) which, when the mechanical control is actuated, selectively and releasably interconnect a portion (2) of the sheathing tube and a surrounding structure (10) which are biased away from one another, and including a control member (8) movable with the cable (1) when the mechanical control is actuated, characterized in that it comprises an electrical line means (21-21', 17,210) incorporating a pair of interacting electrical contacts (20,20';1 6) carried respectively by the control member (8, 7) and an element (4) of the locking device fixedly connected to said first portion (2) of the sheathing tube.

2. A mechanical cable control according to Claim 1, characterised in that the electrical line means comprises at least one electrical line portion (21, 21', 17) extending in the first sheathing-tube portion (2).

3. A mechanical cable control according to Claim 1 or Claim 2, incorporating a locking device with wedging balls (6) carried by a cage part (7) of the control member (8), characterised in that the said element of the locking device consists of a metal sleeve (4) received in the cage part (7) and possessing, at one end, a frustoconical peripheral surface (5) forming a cam for actuating the wedging balls (6), a first contact of the said pair of contacts being formed by a front face (16) of the sleeve (4) capable of interacting with at least one second contact (20, 20') of the said pair of contacts, which is attached to an adjacent axial end wall (15) of the cage (7).

4. A mechanical cable control according to one of Claims 2 and 3, characterised in that it incorporates a spacer spring (12) arranged between an intermediate zone (13) of the first sheathing-tube portion (2), coaxially with the latter, and said surround structure (10).

5. A mechanical cable according to Claim 4, characterized in that the electrical line portion (21,21', 17) extends in the first sheathing-tube portion (2) beyond the intermediate zone (13) of the first sheathing-tube portion (2) in the opposite direction to said surround structure (10).

6. A mechanical cable control according to Claim 5, characterised in that the electrical line portion (21, 21', 17-210) projects outside the first sheathing-tube portion (2) beyond the said intermediate zone (13) of the latter and possesses a means of connection (22, 22') to an outer electrical line (23, 23').

7. A mechanical cable control according to one of Claims 3 to 6, characterised in that it incorporates two separate electrical line portions (21, 21', 17) extending in the first sheathing-tube portion (2).

8. A mechanical cable control according to Claim 7, characterised in that the two separate line portions (21, 21') are connected respectively to two second separate contacts (20, 20') attached to the said cage (7).

9. A mechanical cable control according to Claim 7, incorporating a sheathing tube provided with a helical metal winding (17) which is sheated (1 8), characterised in that the end of the first sheathing-tube portion (2) is fitted into a housing (3) of the sleeve (4), with the metal winding (17) bared in electrical contact with the wall of the housing (3), this metal winding (1 7) forming one of the two electrical line portions.

10. A mechanical cable control according to any of the preceding claims, charactrised in that said surrounding structure is a tubular housing (10) fixedly connected to a second portion (2') of said sheathing-tube axially offset from said first portion (2) of said sheathing-tube.

11. A mechanical cable control substantially as hereinbefore described with reference to and as illustrated in, the accompanying drawings.