FR2780474A1 - Mechanical locking device for vehicle automatic gearbox control lever - Google Patents

Abstract

The locking device comprises a pivoting catch (12) able to occupy immobilizing or releasing positions of the lever (8). The catch is operated by a traction cable (19) connected at one end to the catch and at the other to a push button (23) on which an angled rod (27) is supported. The rod tips around an axis (5) around which pivots the compensator (2) of the brake pedal (1).

Description

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  The present invention relates to a device which makes it possible to lock or unlock on demand the pivoting lever of a gear selector of an automatic gearbox for a motor vehicle, in particular when this lever is brought into a determined position and more particularly in that which corresponds to the "Parking" of this vehicle, the box then being disconnected from the engine components. Current regulations for manufacturers impose on vehicles that include a gearbox of this kind, the presence of a system known by the English term "Shift-Lock", whose role is to prevent the lever is only extracted from the "Parking" position of the selector if the brake pedal is

pressed by the user.

  In addition, this system must allow, when this position is reached again, that the locking of the lever

takes place automatically.

  Many systems, in particular with electromagnetic control of the selector lever locking lock, have already been proposed in the art, as also entirely mechanical devices, such as for example that described in the European patent application

published EP-A-0 372 858.

  This document illustrates a device for controlling the brake pedal causing the displacement of a locking finger against a spring, this finger normally being engaged in a housing forming a keeper, formed in a locking wheel which immobilizes the gear selector lever. When the pedal is depressed and the wheel is released by being able to turn on itself, it releases the lever which can then be maneuvered to

  select another position in the box.

  With regard to fully electromagnetic systems, such a device has the advantage of being simpler since it requires no electrical connection, no more than the implementation of a backup mechanism in the event of

  failure of the electrical part.

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  However, when the brake pedal is depressed strongly, which frequently happens during the use of the vehicle, the elements of the device are subjected to stresses.

  significant, hence a risk of premature wear.

  The subject of the present invention is an entirely mechanical device which avoids these drawbacks, by making it possible to decouple the blocking system from

  the brake pedal beyond a certain stroke of it

  Ci, this system thus only undergoing the efforts which are

  strictly necessary for locking the lever.

  To this end, the device in question, comprising a pivoting lock capable of occupying two opposite positions depending on whether it ensures the immobilization or the release of the control lever of the automatic gearbox, the operation of the lock being carried out by a tied pulling cable to the lock at one of its ends, is characterized in that the other end of the traction cable is secured to a pusher on which a bent rod rests, pivotally mounted around an axis which is preferably that around which pivots the lifter of the vehicle brake pedal, the bent rod being in contact with this lifter so that the pivoting of the latter, by depressing the pedal, allows at the start and during a limited fraction of the stroke of this lifter , the tilting of the rod, and produce a tensile force on the cable,

  releasing the bolt from the lever.

  According to another characteristic, the pusher secured to one end of the cable is permanently subjected to the thrust of a spring, axially traversed by the cable and

which rests on a fixed stop.

  According to another characteristic, the calibration of the spring is provided to limit the tilting of the bent rod,

  following the pivoting of the lifter.

  Preferably, the traction cable is sheathed, the sheath of this cable being integral, at a first

end, of the fixed stop.

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  Advantageously, a complementary spring is provided between an additional stop mounted at the opposite end

sheath and latch.

  According to a preferred embodiment, the lock comprises a flat heel, suitable for engaging under a span

  of the control lever to block its rotation.

  Also preferably, the lock is extended by a support, which can rotate about a fixed axis, this axis being able to be perpendicular to the pivot axis of the

spreader.

  According to another characteristic finally, the bent rod has a general S-shaped profile, one of the branches of which is parallel to the pivot axis of the lifter of the brake pedal, and the other rests on the edge

superior of this spreader.

  Other characteristics of a mechanical device for locking a control lever of a gearbox for a motor vehicle, established in accordance with

  the invention will also appear through the description

  which follows of an exemplary embodiment, given by way of non-limiting example, with reference to the appended drawing in which the single figure schematically illustrates, seen in

perspective, such a device.

  In this figure, the reference 1 designates a conventional brake pedal for a motor vehicle comprising a lifting beam 2 and a bearing surface 3, suitably profiled, advantageously provided with a non-slip coating 4, of rubbery or other material, on which the user applies his sole to exert a force on the pedal causing the spreader to rotate around

  a transverse axis 5, in the direction of arrow 6.

  The lifter comprises a sleeve 7 for tilting around the axis 5 and is associated with a conventional return system (not shown), allowing the pedal 1 to return to the initial rest position by pressing on a fixed stop (also not shown). ), when

  the user stops pressing on the support surface 3.

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  Also shown in the figure is a reference 8, comprising a connecting stud 9 with a lever (not shown) forming part of a gear selector of an automatic gearbox with which the vehicle is equipped, the operation of this lever ensuring the pivoting of reference 8 around a

  axis of rotation 10 in the direction of the double arrow 11.

  In what follows, the reference 8 will be assimilated to the lever of

  selector control, to which it is thus connected.

  Conventionally, this lever can occupy various exactly different positions, in each of which the gearbox controls the vehicle's gear ratios, or even completely disconnects the clutch in the so-called "Neutral" position, or finally can be placed in a

another position, called "Parking".

  To extract the lever from the latter and according to the construction rules in force, the vehicle must have

brake pedal depressed.

  The invention therefore aims to provide a locking system for the lever of the gear selector, therefore in the example shown of the reference 8 linked to this lever, when the latter

  is brought to the "Parking" position.

  To this end, the device comprises a lock 12, provided with a flat heel 13, one edge of which is suitable for coming against a bearing surface 14 of the reference 8 of the control lever, to prevent rotation thereof around the axis 10. The latch 12 has an extension forming a support, provided with a head 16 which can rotate about an axis 17, which, in the example described here, is substantially perpendicular to the axis 5 of pivoting of the lifter, the bolt thus moving in its plane between a position o it releases the reference 8 and a position o its heel 13

  blocks the latter, by cooperating with the bearing surface 14.

  At its opposite end, the lock 12 is provided with an end piece 18 for connection with the end of a traction cable 19, housed in a sheath 20, which is secured at its two ends with stop parts,

21 and 22 respectively.

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  The cable 19, beyond these abutment parts, is linked, on the one hand to the end piece 18, on the other hand to a pusher 23,

  whose role is defined below.

  A spring 24 is mounted between the abutment piece 21 and the end piece 18 to allow, as the case may be, the displacement of the lock 12 following a tensile force on the cable 19, this lock releasing the reference 8 by escaping its heel 13 in range 14, that is to say the reverse of this lock in the position for blocking the return, these movements being shown diagrammatically in the figure

by the double arrow 25.

  At its opposite end, the traction cable 19 is surrounded by another spring 26, mounted between the stop piece 22 and the pusher 23, this spring normally exerting a traction force on the cable, holding the lock 12

  in the position where it releases the reference 8.

  According to the invention, the pusher 23 is designed to cooperate with a bent rod 27, having a general S-shaped profile and one end 28 of which, which extends substantially parallel to the pivot axis 5 of the lifter 2, ends in a support rim 29, applied to the pusher 23 due to the presence and mounting of the

spring 26.

  At its opposite end, the bent rod 27 comprises a transverse branch 30, the end part of which 31

  rests on the upper edge of the lifter 2.

  The bent rod 27 is thus held at its two ends 29 and 31 and is supported on the sleeve 7 around which it can tilt according to the respective movements, either of the pusher 23 which causes an upward movement of its end 29 or of the lifter 2 which allows its end 31 to fade down over a given stroke when the brake pedal is depressed, or of the lifter 2 which causes an upward movement of its end 31 when the brake pedal is released. The double arrow 32 diagrams the corresponding displacements of the

bent rod.

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  The operation of the device described above is as follows: It is assumed that, in the "Parking position, which corresponds to that illustrated in the figure, the heel 13 of the lock 12 is in contact with the bearing surface 14 of the reference 8 and

  This therefore blocks the gear selector lever.

  If the brake pedal 1 is depressed, the bent rod 27, which initially accompanies the movement of the latter, switches with the lifter 2, its end 29 allowing the pusher 23 to move upward, exerting on the cable 19 , thanks to the spring 26, a tensile force, which in turn rotates the lock 12 around the axis 17 and

  releases reference 8, therefore the selector lever.

  When the brake pedal is released and the gear lever is not in the "Parking" position, the heel 13 is applied to the gear 8 without immobilizing it until the bearing 14 comes opposite of the heel and allows it, under the effect of the thrust of the spring 24, to

  engage against this scope by blocking the dismissal.

  The advantage of the device lies in the fact that, thanks to the presence of the springs 24 and 26, the brake pedal 1 no longer acts on the bent rod 27 beyond a

certain race.

  Thus, the traction exerted on the cable no longer corresponds to that which would be due to the pivoting movement of the brake pedal 1, if the pusher 23 was directly

linked to it.

  With the invention, the action exerted on the cable is due, not directly to the pedal, but to the assembly constituted by the bent rod and the two springs, the effect of the pedal being decoupled from the rod au- beyond a race

  given, function of spring setting 24.

  The proposed device therefore makes it possible to limit the tensile forces on the cable 11 and on the locking mechanism, by an entirely mechanical assembly which does not require

no adjustment during operation.

  Note that the bent rod 27 may be provided heavier, relative to the axis 5, either on the side of its

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  end 29, ie on the side of its end 31. In the first case, it remains in permanent contact with the plunger 23 and separates from the brake pedal beyond a certain stroke of the latter. In the second case, it remains permanently in contact with the pedal and separates from the pusher 23 when the spring 26 is at its maximum extension. This latter arrangement avoids noise due to contact of the lifting beam 2 on the rod if the pedal

is released abruptly.

  Of course, it goes without saying that the invention is not limited to the embodiment more specifically described above with reference to the accompanying drawing; she in

  on the contrary embraces all variants.

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Claims (7)

  1 - Mechanical device for locking the control lever (8) of an automatic gearbox for a motor vehicle, comprising a pivoting lock (12) capable of occupying two opposite positions depending on whether it immobilizes or releases the lever , the operation of the lock being carried out by a traction cable (11) linked to the lock at one of its ends, characterized in that the other end of the traction cable is secured to a pusher (23) on which a bent rod (27), pivotally mounted around an axis (5) which is preferably that around which the lifter (2) of the vehicle brake pedal (1) pivots, the bent rod being in contact with this lifter so that the pivoting thereof, by depressing the pedal, allows at the start and during a limited fraction of the stroke of this lifter, the tilting of the rod, and produces a tensile force on the cable, releasing the lock vis-à-vis the the sink.   2 - Device according to claim 1, characterized in that the pusher (23) integral with one end of the cable (19) is permanently subjected to the thrust of a spring (26), axially traversed by the cable and which rests on a fixed stop (22).   3 - Device according to claim 2, characterized in that the calibration of the spring (26) is provided to limit the tilting of the bent rod (27), following the pivoting of the lifting beam (2).   4 - Device according to one of claims 2 or 3,   characterized in that the traction cable (11) is sheathed, the sheath (20) of this cable being integral, at a first   end, of the fixed stop (22).   - Device according to claim 4, characterized in that a complementary spring (24) is provided between an additional stop (21) mounted at the opposite end of the sheath (20) and latch (12). 9 2780474   6 - Device according to any one of   Claims 1 to 5, characterized in that the lock (12)   has a flat heel (13), suitable for engaging against a bearing surface (14) of the control lever (8) to block its rotation. 7 - Device according to any one of   Claims 1 to 6, characterized in that the lock (12)   is extended by a support (15) which can rotate around a fixed axis (17).   8 - Device according to claim 7, characterized in that the fixed axis (17) extends perpendicularly to   the pivot axis of the lifter (2).   9 - Device according to any one of   Claims 1 to 8, characterized in that the bent rod   (27) has a general S-shaped profile, one of the branches of which is parallel to the pivot axis of the lifter (2) of the brake pedal, and the other rests on the   upper edge of this lifter.