GB2253446A

GB2253446A - A gearchange lever with snap-fitted parts for a motor vehicle

Info

Publication number: GB2253446A
Application number: GB9204978A
Authority: GB
Inventors: Carlo Beccaris; Gianfranco Piovano
Original assignee: Valeo SE
Current assignee: Valeo SE
Priority date: 1991-03-08
Filing date: 1992-03-06
Publication date: 1992-09-09
Anticipated expiration: 2012-03-06
Also published as: FR2673733B1; GB2253446B; FR2673733A1; GB9204978D0; DE4206052A1

Abstract

A motor vehicle gearchange lever comprises a lower part (3) and an upper part (1) carried by the lower part (3), together with coupling means comprising a spigot (4) of the lower part of the lever fitted in mating relationship in an open cavity (40) which is delimited by a wall of a support or body member (100) defining an envelope. This element is part of the upper part (1) of the lever. The coupling means also include snap-fitting means comprising a pin (5) carried by the body member (100) and mounted slidingly in a hole formed in the envelope wall of the body member (100), together with a complementary socket formed in the spigot (4) for receiving the pin (5). The latter is attached to a spring clip (7) carried by the body member (100) and biassing the pin (5) into the cavity (40) for engagement of the pin with the socket (6). <IMAGE>

Description

1 A GEARCHANGE LEVER FOR A MOTOR VEHICLE 2 2 5 5 4 4 6

This invention relates to gearchange levers for motor vehicles, of the kind comprising: a downstream part adapted to be coupled to a control mechanism for a speed changing device, typically the gearbox of the vehicle; a downstream part carried by the upstream part and provided with a knob for actuation by the user (referred to in this description as the driver); and coupling means for coupling the upstream part with the downstream part and comprising a spigot of the downstream part fitted in mating relationship in an open cavity which is delimited by an envelope defined by an element of a support member which is fixed with respect to the upstream part or which is part of the upstream part.

The terms "upstream" and "downstream" relate to the direction in which force is transmitted between the hand of the driver and the gearbox control mechanism. In the rest of this description, and in the Claims, the upstream and downstream parts of the lever will be referred to as the upper and lower parts respectively.

A gearchange lever of the above kind is described in French published patent specification FR 2 575 707A, in Figure 1 of which the upper part of the lever is able to be displaced angularly with respect to the lower part of the lever. Force threshold detecting means are arranged to operate between the two parts of the lever, for the purpose of detecting pressure on the knob by the driver which indicates an attempt to manoeuvre the lever. These detecting means comprise electrical sensors together with resilient return means. The above mentioned spigot is part of a nose of the lower part of the lever, and is attached

2 by welding to the support member, which encloses the electrical sensors and defines the terminal end of the upper part of the lever.

Final assembly of the two parts of the lever is achieved by welding, which somewhat complicates the assembly operation. It is often desirable to make in one place a sub-assembly comprising the upper part of the lever together with various components such as the electrical sensors, with this sub-assembly being subsequently fitted on to the lower part of the lever in an easy and rapid manner, in a different part of the factory.

An object of the present invention is to satisfy this requirement in a simple and cost-effective manner by providing an arrangement whereby a sub-assembly comprising the upper part of the lever can quickly and easily be finally fitted on to its lower part.

According to the invention, there is provided a manual gearchange lever for a motor vehicle gearbox, comprising: a lower part adapted to be connected to an actuating mechanism for the gearbox; an upper part which is carried by the lower part and which has a knob adapted to be operated by a driver of the vehicle and a support member fixed with respect to the knob; and coupling means coupling the upper part with the lower part and comprising a spigot of the lower part mated in an open cavity which is delimited by an element of the support member, wherein the coupling means further include a pin, carried by the said support member and mounted for sliding movement in a hole formed in the said element of the support member, together with a complementary reception hole in the spigot for receiving the said pin and resilient return means carried 3 externally by the support member attached to the pin so as to bias the pin towards the cavity for engagement of the latter with the reception hole whereby to constitute a snap-fitting means.

The invention enables a sub-assembly to be created which consists of the knob with a cartridge type unit which contains any sensors that may be provided, with this subassembly being able to be taken elsewhere as a complete unit for final fitting on the spigot of the lower part of the lever. This fitting can be carried out blind, with the two parts being secured together by simple snap-fitting.

In one embodiment of the invention, the resilient return means are in the form of a broken ring of spring steel sheet mounted outside the element defining the cavity in the support member.

Disassembly of a lever according to the invention is also easy in all cases.

Preferably means are provided for absorbing clearances or play. These means may for example consist of 0-rings mounted in the base of the cavity and in its open end. This further facilitates the fitting operation.

A gearchange lever according to the prior art, and one in accordance with the present invention, will now be described and compared, the specific embodiment of the invention being described by way of example only, all with reference to the accompanying drawings, in which:-

Figure 1 is a view in cross section showing a compound gearchange lever of the kind described in French published patent specification No. FR 2 575 707A;

4 Figure 2 is a simplified view in cross section, generally similar to Figure 1 but showing part of a gear lever in accordance with the present invention; Figure 3 is.a view in cross section showing, on a larger scale, the lower part of the lever shown in Figure 2 in the fully fitted position; Figure 4 is a view in cross section taken on the line 4-4 in Figure 2 in the fully fitted position of the lever; Figure 5 is a view similar to Figure 3 but showing the lever in an intermediate fitting position; and Figure 6 is a view similar to Figure 4 but showing the lever in an intermediate fitting position.

In both the prior art arrangement shown in Figure 1 and the arrangement in accordance with the invention shown in Figures 2 to 6, the gearchange lever is a polarised gearchange lever. It includes force threshold detecting means acting between the upper and lower parts of the gear change lever (as defined above), for detecting an attempt by the driver to operate the lever. This force threshold detecting means comprises at least one electrical sensor together with resilient return means, which serve two purposes. Firstly, they restore the upper and lower parts of the lever into alignment with each other when the lever is not subject to hand pressure by the driver, and secondly they cause electrical signals to be generated by means of the sensor, beyond a predetermined force threshold when hand pressure is applied by the driver to the lever in either one of two opposed directions.

Referring first to Figure 1, in this known arrangement the upper part 11A of the gearchange lever includes a portion 191A of increased radial extent (referred to herein as a knuckle) associated with electrical contact zones 231 and 211, while the resilient return means consist of a coil spring 34 which is carried by a coaxial sleeve 33. The upper part-11A is mounted within a tubular body member 201. The spring 34 acts through the sleeve 33 to bias a shoulder 30 on the upper side of a part-spherical knuckle 181 of the upper part 11A, into engagement against an annular surface 32 of the body member 201, so as to provide a return facility. The body member 201 is fixed to a support element which is itself fixed with respect to the lower part of the gearchange lever. This support element is defined by an open cavity which is bounded by an envelope.

The electrical contact zones 211 and 231 consist of contact strips disposed in the body member 201. Thus, when a force is applied to the upper part 11A of the lever, the shoulder 30 becomes inclined with respect to the annular engagement surface 32, while a lower shoulder 31, formed on the lower side of the upper knuckle 181, remains in contact with the sleeve 33A, which tilts until it comes into contact with one or other of the contact strips 211 or 231 to complete the appropriate electrical circuit. This circuit transmits a signal to a computer (not shown) for controlling a clutch.

For more detail of the arrangement described in Figure 1, reference is invited to the above mentioned French patent specification No. FR 2 575 707A, which is incorporated in this specification by reference. Such an arrangement can be incorporated in the gearchange lever in accordance with the present invention, and will not be described in any further detail here.

6 Reference is now made to Figures 2 to 6, again showing a gearchange lever for controlling the changing of gear ratios in a motor vehicle gearbox. This lever comprises a lower part 3 which is adapted to be coupled in any known manner to a control mechanism for the gearbox (not shown), together with an upper part 1. The upper part 1 is carried by the lower part 3, and includes a knob 2 for engagement by the driver's hand, together with coupling means for coupling the upper part 1 with the lower part 3 of the lever. This coupling means comprise a spigot 4 of the lower part 3, in mating engagement in an open cavity 40 which is defined by a tubular wall 41 defining an envelope around the cavity 40 (Figures 3 to 6), the latter being part of a generally tubular body member 100 forming a fixed part of the upper part 1 of the lever.

The coupling means further include a radial pin 5 carried by the body member 100, and a complementary radial socket 6 which is formed in the spigot 4 and which receives the pin 5. The pin 5 is mounted for sliding movement in a radial hole 8 formed in the tubular wall 41 of the body member 100. The pin 5 is connected to a resilient return means 7 carried on the outside of the body member 100, and arranged to bias the pin 5 radially inwardly into the interior of the open cavity 40, so as to engage the pin in the socket 6.

In this particular example, the spigot 4 is in the form of a cylinder having a circular cross section and being part of a nose projecting upwardly from the remainder of the lower part 3 of the lever at the upper free end of the latter. The spigot 4 is here joined through a root radius and a radial shoulder to the shank of the lower part 3, as is best seen in Figure 3. The upper end of the spigot 4 has a penetrating head portion 44. This latter may have a 7 partial ogee shape, but in this example and as shown, it comprises a simple frusto-conical portion. The spigot 4 and cavity 40 are of complementary shapes.

The open cavity 40 consists of a coaxial blind hole formed in the lower free end of the body member 100. An annular groove 42 in the mouth of the blind hole 40 contains an 0ring 10 for absorbing clearances or play, in a manner described below. A further 0-ring 9 is fitted in the upper end, or base, of the hole 40. The hole 8, formed through the wall 41 of the body member 100, has a chamfered outer end, thus bringing the interior of the cavity 40 into communication with the outside. In this example the hole 8 is formed about halfway along the length of the cavity 40.

The pin 5, which like the complementary hole 8 is cylindrical, has a penetrating head portion 51 and a tail portion 52 which is coupled to the resilient return means 7. The latter embraces the envelope wall 41 surrounding the cavity 40 externally over at least part of the periphery of the wall 41. In this example the return means 7 are in the form of a spring clip which is circumferentially deformable and adapted to assume, in the fully assembled position, the retracted position shown in Figure 4, in which the clip 7 surrounds at least the greater part of the wall 41, while during assembly it can assume deployed positions as indicated in Figure 6. In these latter positions it is only partly in contact with the wall 41. In this example, the clip 7 is in the form of a broken ring made from a leaf of spring steel. It is generally in the form of a C. The head portion 51 of the pin 5 is chamfered, and is fastened to the clip 7 by its tail portion 52, which is formed with a rivet head 50 for this purpose. The pin 5 is attached to the clip 7 at the 8 middle of the latter in both the circumferential and transverse directions as seen in Figures 4 and 6, and in Figures 3 and 5, respectively. It can thus be seen that the pin 5 and clip 7 together form a movable sub-assembly, with the pin 5 being in piston-and-cylinder relationship with the radial hole 8.

In a modification (not shown), the clip 7 may be replaced by a ring of resiliently deformable material which is secured on the pin 5, with this ring completely surrounding the envelope wall 41 when fitting is completed.

The socket 6 formed in the spigot 4 is a blind hole, the position of which with respect to the free end of the socket 4 is a function of the depth of the cavity 40 and the position of the radial hole 8, so that in the assembled position shown in Figure 3, a slight clearance exists between the end of the spigot 4 and the base of the cavity 40. The socket 6 is cylindrical, with a shape complementary to that of the pin 5, so that assembly of the gearchange lever is easy to carry out blind by simple snapfitting, to achieve mounting of the lower part 3 of the lever in both the rotational and translational senses with respect to the body member 100, the spigot 4 being confined within the interior of the cavity 40.

In the assembly operation, after a sub-assembly comprising the upper part 1 of the lever, the knob 2, the body member 100, and, optionally, a device comprising force threshold detecting means has been made, this subassembly is taken for final assembly in a second step of the operation. This is carried out by fitting the wall 41 over the spigot 4 in the direction of the arrow A in Figure 2. Finally, the upper part 1 is rotated as indicated by the arrow B in 9 Figure 2, so as to bring the pin 5 into alignment with the socket 6 so that the assembly is completed by snap-fitting.

It will be noted that during the fitting operation the head portion 44 of the spigot 4 is brought into contact with the head portion 51 of the pin 5 (see Figure 5). As the spigot 4 penetrates further into the cavity 40, the pin 5 is pushed radially outwards against the force exerted by the spring clip 7, until it occupies the fully deployed position seen in full lines in Figure 6. on further penetration of the spigot 4 into the cavity 40, the pin 5 then remains in this fully deployed position, until after rotation, the socket 6 comes into alignment with the hole 8 and pin 5. At this moment, the clip 7 relaxes, so as to hug the wall 41 in the final, retracted, position shown in Figure 4, thus bringing the pin 5 into engagement in the blind socket 6.

As will have been understood from the foregoing, the size of the clip 7 is adapted to that of the wall 41, which is cylindrical in this example, and also to the length of the hole 8. The thickness of the wall 41 is therefore so chosen that the pin 5 does not escape from the hole 8 when in its fully deployed position seen in Figure 6. The clip 7 thus acts as a gripper, and initially, before fitting, it is closed up. It is caused to open when the head portion 44 enters into contact with the head portion 51, and subsequently to close for final assembly, with the pin 5 then carrying out a back and forth movement.

Disassembly is of course easy because all that is required for this purpose is to slide a suitable tool between the outer periphery of the wall 41 and the clip 7, as indicated by the arrow C in Figure 5. This opens up the clip 7 and thereby withdraws the pin 5. In the assembled position, the clip 7 is preferably under slight compression, and a clearance separates the base of the socket 6 from the head portion 51 of the pin 5 as seen in Figure 4.

The 0-rings 9 and 10 take up the play or clearances between the body member 100 and the spigot 4. More precisely, the 0-ring 9 is arranged to come into contact with the head portion 44 of the spigot 4, with a clearance then existing between the head portion 44 and the base of the cavity 40. The 0-ring 9 then limits the axial displacement of the spigot 4 with respect to the cavity 40, while the 0-ring 10 gives a gripping effect. It is thus ensured that the pin 5 will penetrate at all times into the interior of the socket 6 regardless of any manufacturing tolerances. In practice, the 0-ring 9 can be compressed by feel to a greater or lesser extent in such a way that the pin 5 will penetrate into the interior of its socket 6.

The present invention is of course not limited to the embodiment described above. In particular, the resilient means for taking up clearances may be in the form of a resilient ring carried by the shoulder which is formed in the junction zone between the spigot 4 and the shank of the lower part 3 of the lever, with this resilient ring being arranged to cooperate with the free end of the body member 100. In a further modification, the O-ring 9 may be replaced by, for example, a ring of the Belleville type. If desired, there may be a plurality of pins 5 and corresponding holes 6 and 8, as required. Finally, the cavity 40 may have a base which is reduced to a simple shoulder for reception of the O-ring 9.

Claims

1. A manual gearchange lever for a motor vehicle gearbox, comprising: a lower part adapted to be connected to an actuating mechanism for the gearbox; an upper part which is carried by the lower part and which has a knob adapted to be operated by a driver of the vehicle and a support member fixed with respect to the knob; and coupling means coupling the upper part with the lower part and comprising a spigot of the lower part mated in an open cavity which is delimited by an element of the support member, wherein the coupling means further include a pin, carried by the said support member and mounted for sliding movement in"a hole formed in the said element of the support member, together with a complementary reception hole in the spigot for receiving the said pin and resilient return means carried externally by the support member attached to the pin so as to bias the pin towards the cavity for engagement of the latter with the reception hole whereby to constitute a snap-fitting means.

2. A lever according to Claim 1, wherein the resilient return means embrace, at least partly, the outside of the said element delimiting the cavity.

3. A lever according to Claim 2, wherein the resilient return means are circumferentially deformable and are adapted to adopt, when assembled, a retracted position in which they at least partly grip the said element, and, during fitting, deployed positions in which they are only partly in contact with the said element.

4. A lever according to any one of Claims 1 to 3, wherein the resilient return means comprise a broken ring, the said pin being fixed to the said ring.

12

5. A lever according to any one of Claims 1 to 4, wherein further resilient means for taking up clearances are provided between the support member and the spigot.

6. A lever according to Claim 5, wherein the means for taking up clearances comprise at least one 0-ring carried in the said cavity.

7. A lever according to Claim 6, in which the cavity consists of a blind hole, and in which the spigot has a penetrating head portion, wherein a said 0-ring is mounted in the base of the cavity, for contact with the head portion of the spigot.

8. A lever according to any one of the preceding Claims, wherein the reception hole is in the form of a blind hole.

9. A lever according to any one of the preceding Claims, in which the spigot has a penetrating head portion, wherein the pin has a further penetrating head portion adapted to cooperate with the penetrating head portion of the spigot.

10. A gearchange lever for a motor vehicle, substantially as described in the foregoing description with reference to Figures 2 to 6 of the accompanying drawings.