EP0406097B1 - Switch, especially for automotive vehicles - Google Patents

Description

The present invention relates generally to electrical switches, in particular for motor vehicles.

Such a switch is described in document FR-A-2 221 801, in accordance with the preamble of claim 1.

In it (Figure 4) a support carries fixed conductive stops and tilting supports. An elastically deformable conductive strip is pivotally mounted for contact with said stops.

An actuating member is mounted mobile on the support and includes a finger for punctual contact with said conductive strip and operation thereof. The conductive strip has two main arms, each for support with one of the tilting supports, as well as a secondary arm for cooperation with said finger of the actuating member.

The main arms form the branches of a U joined at their root by a central section, said secondary arm being disposed between the main arms and ensures contact pressure of the conductive blade in contact with the fixed stops.

In practice, the blade carries a movable contact passing selectively from a contact carried by one of the stops to a contact carried by the other stop, causing current breaks.

Oxidation phenomena occur as well as the formation, on the one hand, of craters, and, on the other hand, peaks at the level of the contacts.

All this is harmful both for the life of the switch and for its performance.

In addition, the finger of the drive member slides along the secondary arm to constrain the blade and tilt it, so that the control force is not as low as desired.

The object of the present invention is to overcome these disadvantages and therefore to create a switch with a long service life, while having a low operating force and providing other advantages.

This problem is solved according to the invention by the characterizing part of claim 1.

Thanks to the invention the elastic blade is axially movable by being driven by the finger of the actuating member cooperating with the tongue and a self-cleaning phenomenon occurs.

Indeed, during the operation of the switch at least one of the main arms first performs a translational movement in contact with the fixed conductive stop concerned, before occupying a second stable position in contact with said stop.

Thus the point of impact of the main arm with its associated stop is different from the point of contact therewith.

It will be appreciated that a low friction contact occurs between the blade and its supports, so that any seizure is avoided and that the operating forces are reduced.

Thanks to the fact that said bearings are in contact with the conductive blade but not to the support, and to the fact that the shaft is centrally in local contact with the support, it is possible to mount the bearings with low friction coefficient, so oscillating, relative to their support.

To do this in one embodiment, the ends of the shaft are each carried by an axial retaining cradle, said end not being in contact with the bottom of the cradle.

For local contact with the support, the tree can have a central barrel shape.

Thanks to this arrangement, the conductive strip finds a third point of contact with the support via the shaft, which improves the floating character.

Advantageously, the secondary arm has a U shape with branches connecting to the free ends of the main arms, said main arms forming the branches of a U inside of which the secondary arm is housed.

Thanks to this arrangement, the secondary arm has a great length and good flexibility, which is favorable for obtaining a good contact pressure of the blade in contact with the fixed stops.

The tongue crosses the plane of the blade and has an inclined portion favoring the tilting of the blade as well as possibly the establishment of a secondary circuit.

According to one characteristic, one of the arms has a projecting contact zone for cooperation with its associated fixed conductive stopper, while the other main arm is smooth for cooperation with a contact zone projecting by its fixed stopper. associated driver. The contact zones can be added contact pads or grains or alternatively tiled or curved zones.

Thanks to this arrangement and to the floating elastic blade according to the invention, the contacts alternate; a first contact area being allowed to enter into action the first, while the second is allowed after wear of the first contact area to cooperate later and vice versa.

The pusher can be capped by a styling element, or alternatively it can be subjected to the action of a rocker available to the user.

Advantageously, the support comprises two half-bodies provided with tracks each connecting to a central part by a hinge. The tracks also have thinned zones so that the assembly is carried out by folding in the manner of a wallet and closing of the two half-bodies by a base.

It becomes possible by changing the bases to obtain either a push button, or a single function rocker key, or a double function rocker key or grouping on a multi-function keyboard.

• la figure 1 est une vue en coupe d'un interrupteur selon l'invention pour l'une de ses positions stables ;
• la figure 2 est une vue en coupe selon la ligne II-II de la figure 1 ;
• la figure 3 est une vue en coupe selon la ligne III-III de la figure 1 ;
• la figure 4 reprend à plus grande échelle en partie la figure 1 ;
• la figure 5 est une vue analogue à la figure 1 pour une première application du type bouton-poussoir ;
• la figure 6 est une vue analogue à la figure 1 pour une application touche basculante simple fonction ;
• la figure 7 est une vue analogue à la figure 1 pour une application touche basculante double fonction ;
• la figure 8 est une vue de face montrant un groupement sur un clavier multi-fonctions ;
• la figure 9 est une vue en coupe selon la ligne IX-IX de la figure 8.

The description which follows illustrates the invention with reference to the appended drawings in which:

• Figure 1 is a sectional view of a switch according to the invention for one of its stable positions;
• Figure 2 is a sectional view along line II-II of Figure 1;
• Figure 3 is a sectional view along line III-III of Figure 1;
• Figure 4 shows on a larger scale in part Figure 1;
• Figure 5 is a view similar to Figure 1 for a first application of the push button type;
• Figure 6 is a view similar to Figure 1 for a single function rocker button application;
• Figure 7 is a view similar to Figure 1 for a dual function rocker button application;
• Figure 8 is a front view showing a grouping on a multi-function keyboard;
• FIG. 9 is a sectional view along the line IX-IX of FIG. 8.

In FIG. 1, the switch for motor vehicles comprises a support 1, preferably made of plastic, carrying fixed conductive stops 2 to 7, each ending in a connection plug, and tilting supports 8, 9.

Here the fixed stops 2 to 7 belong to conductive tracks described below.

An elastically deformable conductive strip 10 is pivotally mounted in the support 1 for contact with some 2.3 of the fixed stops 2 to 7.

An actuating member 20 is movably mounted on the support 1 and comprises a finger 21 for local contact with said conductive strip 10 and operation thereof.

The blade 10 comprises two main arms 22,23 respectively, for contact each with one of the tilting supports 8,9, as well as a secondary arm 24 disposed between the main arms 22,23, for contact with the finger 21. The main arms form the branches of a U by being joined at their roots by a central section 29, while the secondary arm ensures, as described below, a contact pressure of the blade 10 in contact with the fixed stops 2 , 3.

According to the invention said fixed stops 2,3 extend from the side of the free ends of the branches of the U of said blade 10 and are each associated with the free end 25,26 of a main arm 22,23 for cooperation with that -this. Said main arms 22, 23 are each supported on a bearing with a low coefficient of friction 8.9, forming the tilting support. Said bearings 8, 9 are connected and carried by a shaft 50 while being at a distance from the support 1. Punctual contact means are provided between the support 1 and the central part of the shaft 50, for radially oscillating mounting of the bearings 8, 9 and the shaft 50. Coupling means 31.67 are provided between the elastic blade 10 and the actuating member 20 for driving said blade 10 by the actuating member 20. The secondary arm 24 is connected to the free ends of the main arms 22,23. The secondary arm 24 carries centrally, radially projecting, between the two main arms 22, 23 on the side of the central section 29 of the U, a tongue 30 for cooperation with said finger 21 of the actuating member, said tongue 30 comprising a inclined zone 33 allowed to cooperate with the central portion of the shaft 50. The actuating member 20 consists of a pusher mounted movable in translation on the support 1 by means of connecting means to translation 61,62, said pusher 20 being subjected to the action of engagement means 40 urging it towards a first stable position, in which the conductive blade 10 extends away from the fixed contacts 2,3, and being able to occupy a second stable position for which a connection is established between the fixed contacts 2, 3 by the conductive strip 10 maintained in pressure against the latter by virtue of the secondary arms 24.

Thus the blade 10 is coupled by its secondary arm 24 to the pusher 20 for the formation of a movable assembly, said pusher being guided by the support 1.

In the following description, the bearing with a low coefficient of friction 8.9 will be referred to as an anti-friction bearing.

In Figure 1 the pusher 20 is axially movable against elastic engagement means 40 urging it to a first stable position.

In this figure, the anti-friction bearings 8.9 are rolling bodies and consist of rollers 8.9 connected and carried by a shaft 50, the ends of reduced diameter of which are journalled in axial retaining cradles 51 secured to the support. 1 excavated locally for passage of said rollers (Figures 1 to 4).

Here the rollers 8.9 are integral with the shaft 50 and form a single piece of conductive material, the rollers 8.9 being arranged in the vicinity of the internal face of the cradles 51, so that perpendicular to the plane of Figure 2 said cradles 51 constitute stops.

According to an important characteristic, the shaft 50 has a centrally domed barrel shape (FIG. 2) for punctual contact, here indirectly via a track 4, with the support 1.

This barrel part is opposite the tongue 30.

At the level of the cradles 51, the end of the shaft is not in contact with the bottom of the cradle 51, while the rollers 8, 9 are only in contact with the blade 10, the lower part of said rollers being at distance from support 1 thanks to the aforementioned local recesses of the support at the level of the rollers.

As will be understood from this arrangement, the shaft 50 with its rollers 8.9 forms a radially oscillating assembly, its axial movement being limited by the cradles 51.

The secondary arm 24 is connected to the free ends 25, 26 of the main arms 22, 23.

The fixed stops or tracks 2,3 extend parallel to the arms 22,23. Note the presence of track 4 between tracks 2 and 3 allowing the establishment of a function indicator circuit by cooperation with the convex part of the shaft 50.

The free end 25 of the arm 22 (FIG. 2) carries a contact zone 27, for cooperation with the associated stop or conductive track 2, said zone 2 being smooth, The free end 26 of the arm 23 is smooth and is suitable for cooperate with a contact area 28 carried by the other stop or conductive track 3. Here the contact areas 27, 28 consist of pads or contact grains added and provided with silver.

As a variant, the zones 27, 28 can be formed by curved or tiled parts of the parts 10, 3 concerned.

It will be noted that the secondary arm 24 is separated from the main arms 22, 23 by a slot 11, and that the two arms 22, 23 form the branches of a U by being joined at their root by a central section 29.

The arm 24 therefore also has a U shape, housed inside the U carrying the arms 22,23, with a base 12 parallel to the section 29 and branches parallel to the internal contour of the arms 22,23. These arms 22,23 widen in the direction of their free ends 25,26 to increase the contact surfaces with the conductive tracks 2,3 and stiffening of the connection with the branch concerned of the arm 24.

The tongue 30 is in the form of a hook and is erected centrally locally from the base 12 of the arm 24 (FIG. 2). It comprises a radial portion 31 for hooking with the pusher 20, said portion 31 extending by a rounded portion 32 for local and punctual contact with the finger 21 with rounded end.

This tongue 30 extends on the other side of the plane of the blade 10 and has an inclined zone 33 which is able to cooperate with the central barrel portion of the shaft 50.

The pusher 20, advantageously made of plastic, has two rounded local contact surfaces 41, 42 for cooperation with the support 1.

This pusher is of rectangular shape with a narrower front part and a rear part carrying the bearing surfaces 41,42 and connecting to the previous one by an inclined part (see Figures 3 and 4).

The engagement means 40 here consist of a coil spring bearing on the base 60 of the support 1 by surrounding an axial protuberance 61 of cruciform section penetrating into an opening 62 of complementary shape, which has the end or front face 63 of the pusher 20. This pusher 20 has an open upper face for passage of a control lamp 64 making it possible to illuminate the open rear face 65 of said pusher 20.

The bottom 66 of said pusher locally carries the finger 21 with a rounded end, as well as a flared opening 67 for penetration of the portion 31 and hooking of the latter with the pusher 20.

The pusher 20 constitutes a drive member, and the portion 31 with its opening associated 67, coupling means between the blade 10 and the pusher 20.

Thus the pusher 20 and the tongue 30 form an axially movable assembly in both directions, said blade 10 being hooked by its tongue 30 to the pusher 20 guided by the support 1.

The bottom 66 extends partly above the blade 10. One of the lateral faces of the pusher 20 has a labyrinth 70 provided with a central projection 71 and hooking zones 72,73. For the shape of labyrinth 70, refer to FIG. 4.

This form of labyrinth is commonly called "heart-shaped cam".

The support 1 has a slide 74 for sliding a part 75 carrying a hooking stud 76 passing through a slot in the slide 74 and suitable for cooperating with the labyrinth 70 by penetrating therein.

The support 1 has a central front end 80 open and delimited by the base 60. Inside this end are housed the sheets of the stops 2 to 7 here all forming tracks in the form of strips of material parallel to each other, the tracks 5 to 7 being intended in particular for supplying the lamp 64 and offset radially with respect to tracks 2 to 4.

Here the end 80 with its associated plugs, offset radially with respect to the tracks proper, forms the female part of a connection device.

This end 80, in addition to the axial protuberance 61, is integral with half-bodies 81.82 with the presence of thinned zones 83.84 at the connection of each of the half-bodies 81.82 with the base 60.

Tracks 2 to 7 also have thinned areas at this location. They can be overmolded with the half-bodies 81, 82, or as a variant be force-fitted with the presence of pins integral with the half-bodies for maintaining said tracks.

As will have been understood, said thinned zones form hinges so that after mounting of parts of the switch, the assembly of the support is done by folding the half-bodies 81, 82 and confronting them at the way of folding a wallet, the two half-bodies 81, 82 being originally arranged vertically in the plane of FIG. 4.

In this figure there is shown in dotted lines the position of the half-body 81 before folding.

It will be noted that the set of half-bodies 81, 82 thus assembled has a generally parallelepiped shape.

After this folding operation, the whole is locked by a base 90 for fixing to the vehicle, said base 90 comprising for this purpose fixing ears 91 with fixing holes, as well as an axial part for cooperation with the bearing surfaces of guide 41, 42 belonging to the bottom 66 and to the upper wall of the pusher 20.

In FIGS. 1 to 4, the switch is in its first stable position, the spring 40 urging the plunger 20 in contact with the stud 76, the latter being in contact with the attachment zone 72 of the labyrinth 70, the tongue 30 , as well as the finger 21 extending axially from the side of the axis of the shaft 50 turned away from the base 60.

In this configuration, the blade 10 extends at a distance from the tracks 2 and 3, which thus are not connected together so that the associated electrical circuit is open.

It will be noted that the pusher 20 has protuberances 68 for local contact with the ends 25, 26 of the arms 22, 23 in this position.

From the configuration of FIG. 1 if the pusher 20 is pressed, the finger 21 drives the blade 10 thanks to the tongue 30 and the stud 76 traverses the labyrinth until it comes into contact with the second zone of attachment 73 formed on the projection 71.

This configuration corresponds to the second stable position of the switch for which a connection is established between the tracks 2 and 3 by the blade 10 maintained in pressure against them by the arm 24.

During this phase the blade 10 crosses the axis of the shaft 50 and passing on the other side of said axis 50 rocks, one of its main arms 22, 23 coming into rubbing contact with its associated front track, the other main arm.

As will be understood the U-shaped geometry of the secondary arm 24 gives it flexibility so that the blade 10 is floating during its movement.

It will be appreciated that the blade 10 is allowed to first come into contact with one of the tracks, and that it recovers contact with the other track through the rollers 8,9 and the shaft 50 oscillating radially, in so that during its movement it finds three points of contact with the support 1, namely two points of contact with the tracks 2,3 and the third at the level of the central part of the shaft 50.

It will be noted that in this second position the blade 10 allows the establishment of an auxiliary electrical circuit thanks to the shaft 50, to the track 4 and in particular the portion 33 of the blade 10.

If the pusher is pressed again, the pin 76 is unlocked and it returns to its initial starting position under the action of the spring 40, the blade 10 being driven by the pusher 20 thanks to the portion 31.

Of course the pusher 20 can be coated with a style element 95 available to the user as shown in Figure 5, the operation of the switch being by depressing, according to the arrow in this figure.

Alternatively (Figure 6) the drawer can be subjected to the action of a rocker 96 available to the user.

In this case the presence of the labyrinth is no longer necessary and this is obtained by mounting a new base 100. Said base 100 then carries pivots 98 for tilting mounting of the rocker 96, which laterally carries projections 99 specific to s' each engage in a corresponding hole in the base 100 for each position of the pusher 200 and holding it in position.

To do this, the pusher 200 has an appendage 97 in the extension of its bottom 66.

During the operation of the rocker 96, the latter presses on the appendage 97 and moves the drawer 200.

By mounting head-to-tail the supports 130,140 with their pushers 201,202 and standard associated blade 10, it is possible to obtain (FIG. 7) a double function rocking key.

Of course (FIGS. 8 and 9) with a base 190 and supports with elastic blade and standard push-button, it is possible to obtain a multi-function keyboard with rocking keys single function or double function and keys of the push button type, subsequent mounting. of certain supports remaining possible.

Of course, the present invention is not limited to the embodiments described.

In particular, the rolling bodies may consist of ball bearings, and the anti-friction bearings in profiled bearings with a low coefficient of friction.

For example, said bearings can be radially interposed between the blade 10 and the ends of the shaft 50 while being immobilized in rotation by the cradles 51.

The rollers can be separated from each other. The coupling of the pusher 20 to the tongue 30 can be carried out using the finger 21 and an attached piece on the pusher and forming a hook engaging in the slot 11 for recalling the blade 10. Instead of 'a crossbar 61 of cross-section, one can use a translational connection by flat or other.

The secondary arm 24 may consist of a flexible strip connected to the main arm 22, 23. In all cases the current can pass from one main arm 22, 23 to the other, also through the secondary arm 24, so that the voltage drops are reduced.

As a variant, for the formation of a point contact, the shaft 50 may have a cylindrical shaped thickening centrally adapted to cooperate with a strip of material extending transversely with respect to said shaft.

In this case, as in that of FIG. 2 described above, provision is made for punctual contact between the support 1 and the central part of the shaft 50, this contact being made either directly or indirectly via from track 4.

Of course, the fixed stops 2, 3 may very well not be parallel to each other, because one carries a projection for cooperation with the blade 10.

Claims (12)

1. An interruptor, in particular for motor vehicles, of the kind comprising a support (1), carrying at least two fixed conductive abutment elements (2, 3) and tilt contact elements (8, 9), a tilting and resiliently deformable conductive strip (10) for contact with the said fixed abutment elements (2, 3), and an actuating member (20) which is mounted for movement on the support (1) and which comprises a finger (21) for local contact with the said conductive strip (10) and for manoeuvring the latter, wherein the said conductive strip (10) comprises, firstly, two main arms (22, 23) defining the branches of a U joined at their root by a central portion (29), for contact of each main arm with one of the tilt contact elements (8, 9), and secondly, a secondary arm (24) disposed between the main arms (22, 23) for cooperation with the said finger (21) of the actuating member (20), and for providing contact pressure for the conductive strip (10) in contact with the fixed abutment elements (2, 3), characterised in that the said fixed abutment elements (2, 3) lie beside the free ends of the branches of U of the said strip (10), each fixed abutment element being associated with the free end (25, 26) of one main arm (22, 23) for cooperation with the latter, in that each of the said main arms (22, 23) is in engagement on a bearing (8, 9) having a low coefficient of friction and constituting the tilt contact element, in that the said bearings (8, 9) are joined together and carried by a spindle (50), being spaced away from the support (1), in that point contact means are arranged between the support (1) and the central portion of the spindle (50), for mounting the bearings (8, 9) and spindle (50) for radial oscillation, in that attachment means (31, 67) are arranged between the resilient strip (10) and the actuating member (20), for operation of the said strip (10) by the actuating member (20), in that the secondary arm (24) is connected to the free ends of the main arms (22, 23), in that the secondary arm (24) carries, projecting radially between the two main arms (22, 23) beside the central portion (29) of the U, a central tongue (30) for cooperation with the said finger (21) of the actuating member (20), the said tongue (30) including an inclined zone (33) for cooperation with the central portion of the spindle (50), and in that the actuating member (20) consists of a push button which is mounted for linear movement on the support (1) by means of linearly displaceable coupling means (61, 62), the said push button (20) being subjected to the action of engagement means (40) urging it towards a stable first position, in which the conductive strip (10) lies away from the fixed contacts (2, 3), the push button being able to occupy a stable second position in which a connection is established between the fixed contacts (2, 3) by the conductive strip (10) being held under pressure against the latter by means of the secondary arms (24).
2. An interruptor according to Claim 1, characterised in that the secondary arm (24) is U-shaped and is joined to the free ends (25, 26) of the main arms (22, 23), being disposed inside that which comprises the main arms (22, 23), and in that the tongue (30) is carried by the base (12) of the U of the said secondary arm (24).
3. An interruptor according to Claim 1 or Claim 2, characterised in that the said bearings (8, 9) having a low coefficient of friction are connected to a spindle (50), the ends of which are mounted in cradle elements (51) for axial retention, having local openings for passage of the said bearings (8, 9), and hold the latter spaced away with respect to the support (1).
4. An interruptor according to Claim 3, characterised in that the bearings (8, 9) having a low coefficient of friction consist of rolling bodies in the form of rollers (8, 9), mounted on the ends of the spindle (50), the central portion of which is barrel-shaped.
5. An interruptor according to Claim 3 or Claim 4, characterised in that the central portion of the spindle (50) is adapted to cooperate with a supplementary power supply strip (4), and in that the said rollers (8, 9) and the said spindle (50) are of metal.
6. An interruptor according to any one of the preceding Claims, characterised in that the fixed conductive abutment elements (2, 3) consist of conductive contact strips (2, 3) which extend parallel to the main arms (22, 23), and in that one (22) of the main arms (22, 23) carries a projecting contact zone (27) for cooperation with its associated conductive strip (2), which is smooth, while the other main arm (23) is smooth for cooperation with a projecting contact zone (28) carried by its associated conductive strip (3)
7. An interruptor according to any one of Claims 1 to 6, characterised in that the tongue (30) is hook-shaped, and extends centrally and locally from the base portion (12) of the secondary arm (24), and in that the tongue (30) comprises a radial portion (31) penetrating into an aperture (67) of the push button (20) for hooking engagement with the latter.
8. An interruptor according to Claim 7, characterised in that the said radial portion (31) is extended by a rounded portion for local point contact with the finger (21) having a rounded end.
9. An interruptor according to any one of Claims 1 to 8, characterised in that the push button (20) is guided by an axial projecting element (61), having a cruciform cross section and fixed to the support (1), and in that the engagement means (40) consist of a coil spring which bears on the support (1) and on the push button (20), with the said spring (40) surrounding the said axial projecting element (61).
10. An interruptor according to any one of Claims 1 to 9, characterised in that the push button (20) has a lateral face formed with a labyrinth (70) having a central projection (71) and hooking zones (72, 73), the said labyrinth (70) being a heart-shaped cam.
11. An interruptor according to Claim 1, characterised in that the support (1) has a slide (74) for sliding movement of a member (75) carrying a hooking head (76), which extends through a slot in the slide (74) and which is adapted to cooperate with the labyrinth (70) by penetrating into the latter
12. An interruptor according to any one of the preceding Claims, characterised in that its support (1) comprises two half-body members (81, 82), each of which is joined to a central portion (80) through zones (83, 84) of reduced thickness.

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