VEHICLE HORN CONTROL DEVICE

Abstract

Vehicle horn control device, embedded on a vehicle steering wheel, comprising: a base part (10); a control part (20), movable between a rest position and a depressed position; elastic return means (31), for pushing back the control part (20) to the rest position,—positioning means (41); an electrical circuit with at least one switch comprising a second contact terminal (51; 151; 251a, 251b; 21, 452), embedded on the control part (20), and a first contact terminal (52; 152; 252; 441), secured to the base part (10), characterized in that the positioning means (41) comprises the initial contact terminal (52; 152; 252; 441) arranged to position the control part (20) in the rest position, so as to close the switch when the control part (20) is in the rest position.

Claims

1. Vehicle horn control device, arranged to be embedded on a vehicle steering wheel, comprising: a base part, a control part, movable with respect to the base part between a rest position and a depressed position, at least one elastic return feature, arranged to push back the control part from the depressed position to the rest position, at least one positioning feature, arranged to impose the rest position to the control part, an electrical circuit with at least one switch comprising a second contact terminal, embedded on the control part, and an initial contact terminal, secured to the base part, characterized in that the positioning feature comprises the initial contact terminal which is arranged to position the control panel in the rest position, so as to close the switch when the control part is in the rest position.

2. Control device according to claim 1, wherein the positioning feature is a stopping feature comprising the first contact terminal which is arranged to form a mechanical stop at the control part returned to the rest position by the elastic return feature.

3. Control device according to claim 1, wherein the positioning feature is a guide feature wherein: one from the first contact terminal or from the second contact terminal is part of a sliding bar and the other from the first contact terminal or second contact terminal is part of a slide, so as to guide the control part recalled to the rest position by the elastic return feature.

4. Control device according to claim 3, wherein the sliding bar comprises a terminal portion which conducts electricity, and an electrically insulating portion, the slide is formed by a female part arranged at least partially around the sliding bar.

5. Control device according to claim 1, wherein the positioning feature comprises a rod forming the first contact terminal, which conducts electricity and which is part of the electrical circuit.

6. Control device according to claim 5, wherein the rod is shouldered.

7. Control device according to claim 1, wherein the base part is in electrically conducting material and is part of the electrical circuit.

8. Control device according to claim 7, wherein the base part is arranged to be electrically insulated from the mass of the vehicle

9. Control device according to claim 1, wherein the positioning feature comprises an insulation part, which is electrically insulating, wherein one from the first contact terminal or second contact terminal is a metal portion formed on the insulation part, and wherein the other from the first contact terminal or second contact terminal is a conducting part, arranged to be in contact with the metal portion when the control part is in the rest position.

10. Control device according to claim 1, wherein the positioning feature comprises an insulation part, which is electrically insulating, wherein one of the first contact terminal or the second contact terminal comprises two electrical tracks formed on the insulation part, and wherein the other from the first contact terminal or from the second contact terminal is a conducting part, arranged to be in contact with the two electrical tracks when the control part is in the rest position.

11. Control device according to claim 1, comprising a plurality of switches each having an initial contact terminal and a second contact terminal, wherein the positioning feature comprises a plurality of positioning units, wherein each positioning unit comprises one of the first contact terminals.

12. Control device according to claim 1, wherein a stroke of the control part between the rest position and the depressed position is lower than 1 mm.

13. Control device according to claim 1, wherein the elastic return feature is arranged to exert a return force greater than 20N.

14. Control Device in accordance claim 1 in combination with a vehicle steering wheel.

15. Control device according to claim 1 in combination with a motor vehicle.

Description

[0037] Other features and benefits of the present invention will be seen more clearly from reading of the following detailed description of several implementations of the invention, provided by way of a non-limiting example and illustrated by the appended drawings, wherein:

[0038] FIG. 1 represents an initial embodiment of a horn control device, in a rest position;

[0039] FIG. 2 represents the control device from FIG. 1 in a depressed position;

[0040] FIG. 3 represents a second embodiment of a horn control device, in a rest position;

[0041] FIG. 4 represents the control device from FIG. 3 in a depressed position;

[0042] FIG. 5 represents a third embodiment of a horn control device, in a rest position;

[0043] FIG. 6 represents the control device from FIG. 5 in a depressed position;

[0044] FIG. 7 represents a detail of the control device from FIG. 5;

[0045] FIG. 8 represents a detail of the control device from FIG. 1;

[0046] FIG. 9 represents a detailed view of a component of the control device of FIG. 1;

[0047] FIG. 10 represents a fourth embodiment of a horn control device, in a rest position;

[0048] FIG. 11 represents the control device from FIG. 8 in a depressed position;

[0049] FIG. 1 represents a horn control device mounted on a steering wheel, according to a first embodiment of the invention, and which comprises:

a frame 10 of the steering wheel, forming a base part,
a shoulder screw 41, attached to the frame 10,
a panel 20 comprising a plate 21 with an over-molding 22, guided by a cylindrical part of the shoulder screw,
a washer 51, embedded on panel 20 as it is held by hooks 24 of the over-molding 22,
a spring 31 forming return means and using the frame 10 as a support to push back the washer 51 from the panel 20 against the shouldering of the shoulder screw 41.

[0050] The plate 20 is therefore pushed upwards from FIG. 1 by the spring 31, it is therefore in the rest position, and the plate 20 may slide along the shoulder screw 41 to reach a depressed position, as shown in FIG. 2. The panel 20 thus forms a control part which can be pushed from the rest position in FIG. 1 to the depressed position in FIG. 2 by a user when s/he wants to beep the horn. A contact 23 forms a stopper at the end of the stroke supporting itself on the frame 10.

[0051] In other words, the shoulder screw 41 with the washer 51 form positioning means and in particular stopping means, for positioning the panel 20 in the rest position, since it is pushed back there by spring 31.

[0052] Typically, the panel 20 has an embedded safety module (an air bag) and the user presses on the latter to activate the horn. The safety module is therefore embedded on the panel 20 and is movable with respect to the frame of the steering wheel. However, the control part may be only a lid or a hood of the safety module in another embodiment.

[0053] To detect the movement of the panel, the invention proposes to form an electrical switch with the washer 51 which forms a second contact terminal, and a surface 52 of the shoulder of the shoulder screw 41, which then forms a first contact terminal.

[0054] An electrical circuit is then formed by:

the frame 10,
the shoulder screw 41,
the initial contact terminal (surface 52),
the second contact terminal (washer 51),
an electronics unit 53 linked on one hand to the frame 10 and on the other to the washer 51, and which is arranged to detect the opening of the electrical circuit, i.e. the moment when the washer 51 is no longer in physical and/or electrical contact with the surface 52.

[0055] In other words, the first contact terminal (surface 52) is part of a sliding bar (shoulder screw 41), and the second contact terminal (washer 51) is part of a slide (over-molding 22). However, an inverse construction may be envisaged, i.e. that the first contact terminal can be part of a slide, which could encircle and slide with respect to the second contact terminal which would then be part of a sliding bar.

[0056] As a consequence, the control detection takes place the moment the panel 10 is moved, which procures very rapid detection, and this helps keep the stroke (depicted by clearance “j” on FIG. 1) of the panel at very low values, i.e. lower than 1 mm. It is therefore possible to increase the stiffness of the spring 31 to limit the vibrations, as the stroke is small (therefore the elastic effort slightly increases alongside this small stroke), and it is not even necessary to reach the stopper at the end of the stroke to set off the horn.

[0057] In particular, it is possible to design a stroke less than or equal to 1 mm and preferentially to 0.5 mm, and, even, less than or equal to 0.3 mm. As a consequence, at the level of the movable trim parts there can be a smaller clearance with the static trim parts of the steering wheel than those seen in the prior art. For the prior art, there's a clearance of around 4 mm, and the invention therefore allows this clearance to be reduced to values lower than 2 mm, which improves the quality perceived by the client.

[0058] Alternatively, a clearance “j” can be provided between the movable and static trim parts.

[0059] Several shoulder screws 41 (typically three) can of course be implemented to guide the plate 20, to form several positioning units or terminal units, with the option of forming a switch at the level of each terminal unit. All these switches can be implemented in series, or in parallel from the same electrical circuit with a single electronics unit 53, or an electrical circuit for each switch of each terminal unit can be implemented with an electronics unit 53 to provide several horn activation options: as soon as at least one switch is on, at least two switches are on, or all of the switches are on.

[0060] In this embodiment we can see that the positioning means comprise the rod of the shoulder screw 41 which seen from above, blocks two translations in X and Y, and the surface 52, which blocks a degree of freedom in Z (axis shoulder screw 41). They also comprise the over-molding 22 which blocks a degree of freedom of rotation. With respect to FIG. 1 or 2, it must be understood that the positioning means comprise moreover, for example, an index or another sliding bar/slide subset for blocking seen from above a rotation around the axis of the shoulder screw 41, or axis Z.

[0061] FIGS. 3 and 4 depict a second embodiment of the invention. This second embodiment only differs from the first embodiment in terms of the electrical circuit. The features already described will not be described again.

[0062] In the present case, the electrical circuit is formed by:

a washer 151 embedded on the panel 20, and forming a second contact terminal,
a washer 152 secured to the shoulder screw 41, and forming a first contact terminal,
the electronics unit 53 linked on one hand to the washer 151 and on the other hand to washer 152.

[0063] In the present case, insulation means in the form of a protection 154 are inserted between the head of the shoulder screw 41 and the washer 152. As a consequence, the electrical circuit does not include the shoulder screw 41, nor the frame 10. Likewise, for the first embodiment above, the first contact terminal and the second contact terminal form stopping means and enter into mechanical abutment to close the electrical circuit as soon as the panel 20 returns to the rest position (FIG. 3). The contact is lost as soon as the panel is moved to go into the depressed position (FIG. 4).

[0064] FIGS. 5 to 7 depict a third embodiment of the invention. This third embodiment only differs from the second embodiment in terms of the electrical circuit. The features already described will not be described again.

[0065] In the present case, the electrical circuit is formed by:

two tracks 251a and 251b formed on an insulating washer 255 embedded on the panel 20, and forming a second contact terminal,
a washer 252 secured to the shoulder screw 41, and forming a first contact terminal,
the electronics unit 53 linked on the one hand to the track 251a and on the other hand to the track 251b.

[0066] In the present case, insulation means in the form of a protection 154 are inserted between the head of the shoulder screw 41 and the washer 252 on one hand, and between the two contact tracks 251a and 251b on the other hand (this is the insulating washer 255). As a consequence, the electrical circuit does not include the shoulder screw 41, nor the frame 10. As in the first and second embodiment above, the first contact terminal and the second contact terminal form stopping means and enter into mechanical abutment to close the electrical circuit as soon as panel 20 returns to the rest position (FIG. 5). The contact is lost as soon as the panel 20 is moved to go into the depressed position (FIG. 6). In particular, the washer 252 contacts simultaneously the tracks 251a and 251b, so as to conduct the current from one to the other. This implementation simplifies the connection cabling with the electronics unit since the cabling is only supported by a single part, the panel 20.

[0067] Typically, the horn is supplied with strong current (greater than 4 amps), whereas the electrical circuit of the control device is supplied with weak current (less than 1 amp) to limit any risk of electric arc between the first contact terminal and the second contact terminal.

[0068] FIG. 7 depicts a view from above of the insulating washer 255, with the two tracks 251a and 251b, which can be printed, engraved or bonded to the insulating washer 255.

[0069] FIG. 8 represents an exploded view of the control device in FIG. 1, which comprises in total three positioning units (herein stopping units), each comprising a shoulder screw 41, a washer 51 and a spring 31, so as to guide and put and position the panel 20 into abutment with the frame 10.

[0070] FIG. 9 represents a view of the washer 51, which comprises an electrical connection interface, and two clips to be attached to the panel 20. Thus we can see that the device from FIG. 8 comprises three guide units with each one a first contact terminal (shoulder screw 41), and a second contact terminal (washer 51), so as to form three different switches.

[0071] FIGS. 10 and 11 depict a fourth embodiment of the invention. In the case depicted, the shoulder screw 41 only forms stopping means. A clearance can be observed between the shoulder screw 41 and the over-molding 22 of the panel 20. In this embodiment, a shoulder positioning screw 441 comprises an insulating tube 453 around its cylindrical part, and thus forms a cylindrical positioning contact which cooperates with a cylinder bore 452 of the panel 20 to form positioning means which are guiding means. In effect, in this embodiment, the screw 441, the insulating tube 453 and the cylinder bore 452 of the plate 21 cooperate to block two degrees of freedom of the panel 20 (two translations X-Y, seen from above), and the shoulder screw 41 blocks for its part a degree of freedom (the translation following its axis), so that we see the clearance between the over-molding 22 and the rod of the shoulder screw 41.

[0072] In the present case, the electrical circuit is formed by:

the plate 21 which forms with the cylinder bore 452 a second contact terminal,
the extreme part of the positioning contact (the head of the positioning shoulder screw 441) at the level of its cylindrical lateral surface which forms a first contact terminal,
the electronics unit 53 linked on one hand to the plate 21 and on the other hand to the positioning shoulder screw 441. In other words, the positioning means include the first contact terminal (the head of the screw 441) and the second contact terminal (the cylinder bore 452 of the plate 21). The positioning means also include the insulating tube 453.

[0073] When the panel 20 is in the rest position (FIG. 10), the first contact terminal and the second contact terminal are in electrical contact to close the electrical circuit. The contact is lost as soon as the panel 20 is moved to go into the depressed position (FIG. 11). As a consequence, the electronics unit 53 detects an opening of the electrical circuit and can control the functioning of the horn.

[0074] It will be understood that various modifications and/or improvements obvious to those skilled in the art can be made to the different embodiments of the invention described in the present description, without going beyond the scope of the invention as defined by the appended claims.