Control device, automatic gearbox including a control device, and steering wheel including a control device

Abstract

A control device (100) is proposed, comprising a fixed part (110) including a light source (111) and a light sensor (112), a movable part (120), and an elastic return means interposed between the movable part and the fixed part. The movable part is configured to move against the elastic return means between a first position and a second position along a direction of movement (D'). The movable part includes a reflective portion (121) configured to reflect a beam of light from the light source towards the light sensor when the movable part is in the first position and not to reflect said beam of light towards the light sensor when the movable part is in the second position. The invention also proposes an automatic gearbox and a steering wheel, each comprising such a control device. Figure for the abstract: Fig. 1

Description

Title of the invention: Control device, automatic gearbox comprising a control device and steering wheel comprising a control device technical field

[0001] The present invention relates to the technical field of electronics, and in particular to sending a command using an optical signal.

[0002] The invention relates more particularly to a control device comprising a fixed part and a moving part and configured to send a control signal.

[0003] It also relates to an automatic gearbox comprising such a control device. It also relates to a steering wheel comprising such a control device.

[0004] The invention finds a particularly advantageous application in the control selection of a motor vehicle. Technological background

[0005] Motor vehicles offer more and more adjustable options to their users. In order to control these settings, more and more buttons, switches or control devices are needed in the passenger compartment of the motor vehicle.

[0006] These control devices often operate mechanically. Mechanical operation has two drawbacks. First, the control device wears out and breaks with repeated use. Second, the control device is bulky and cannot be installed in confined spaces. Summary of the invention

[0007] In order to remedy the aforementioned drawbacks of the prior art, the present invention proposes a control device operating by means of optical detection and using a minimum of components, allowing robustness and use in confined spaces.

[0008] More particularly, the invention proposes a control device comprising a fixed part, a moving part and an elastic return means interposed between the moving part and the fixed part, the moving part being configured to move against the elastic return means between a first position and a second position along a direction of movement, the fixed part comprising a light source and a light sensor.

[0009] The moving part includes a reflective portion configured to reflect a A beam of light from the light source is directed towards the light sensor when the moving part is in the first position. The reflective portion is configured not to reflect this beam of light towards the light sensor when the moving part is in the second position.

[0010] Thus, thanks to the invention, the control device uses an optical signal. Furthermore, the control device uses few components, allowing for minimal bulk.

[0011] According to one embodiment, the light source and the light sensor are fixed on a printed circuit board.

[0012] In addition, the direction of movement can be parallel to the printed circuit board.

[0013] In addition, the control device can be configured to send a control signal when the moving part is in one of the two positions.

[0014] The control signal can be sent when the light sensor detects a signal variation greater than a threshold variation.

[0015] In one embodiment, the light source and the light sensor are aligned along the direction of movement. The light source may have a principal direction of illumination perpendicular to the direction of movement. Furthermore, the light sensor may include a photosensitive surface parallel to the direction of movement.

[0016] The light source can generate a cone of illumination around the main direction of illumination.

[0017] For example, the reflective portion may be in this illumination cone when the moving part is in the first position and / or outside this illumination cone when the moving part is in the second position.

[0018] In addition, the first position can be a relaxed position and the second position can be a pressed position.

[0019] The movable part may include an opening configured to allow light from the light source to pass through when the movable part is in the second position.

[0020] For example, the opening can be located outside the illumination cone when the moving part is in the first position and / or in the illumination cone when the moving part is in the second position.

[0021] In addition, the reflective portion can be formed from polished white plastic.

[0022] According to one embodiment, an air gap may be provided between the fixed part and the reflective portion, the moving part may then include a part projecting at an interface of the fixed part and the moving part configured to cover at least part of the air gap.

[0023] The elastic return means may include elastomeric membranes.

[0024] The invention also relates to a gearbox comprising at least one control device as proposed above and configured to send a control signal to a control unit of a motor vehicle.

[0025] The invention also relates to a steering wheel comprising at least one control device as proposed above and configured to send a control signal to a control unit of a motor vehicle.

[0026] The different features, variants and embodiments of the invention can be combined with each other in various ways insofar as they are not incompatible or mutually exclusive. Brief description of the figures

[0027] In addition, various other features of the invention become apparent from the attached description made with reference to the drawings which illustrate non-limiting embodiments of the invention and where:

[0028] [Fig-1] is a schematic representation of part of a control device according to an embodiment of the invention in a first configuration,

[0029] [Fig.2] is a schematic representation of part of the control device of [Fig. 1] in a second configuration,

[0030] [Fig.3] is a schematic representation of the control device of the [Fig.1],

[0031] [Fig.4] is a schematic representation of an automatic gearbox according to an embodiment of the invention,

[0032] [Fig.5] is a calibration curve of the control device of [Fig.1] representing a force required to move from the first position to the second position as a function of the displacement of the moving part, and

[0033] [Fig.6] is a calibration curve of the control device of the [Fig.1] representing the optical signal received by the light sensor of the control device as a function of the displacement of the moving part.

[0034] It should be noted that in these figures the structural and / or functional elements common to the different variants may have the same references. Detailed description

[0035] A control device according to the invention, as schematically represented in Figures 1, 2 and 3 and designated as a whole by reference 100, is a device enabling the sending of a control signal.

[0036] The control device 100 can be implemented in an automatic transmission 200 of a motor vehicle, as shown in [Fig. 4]. The automatic transmission 200 shown here comprises two control devices for sending control signals to trigger adjustments of vehicle transmission ratios. The control devices here are intended to trigger the "P" and "M" positions corresponding respectively to the vehicle's transmission ratio settings in parking mode and manual mode.

[0037] Alternatively, the control device 100 can, for example, be implemented in a steering wheel of the motor vehicle. The steering wheel allows the motor vehicle to be steered. The steering wheel may include at least one control device 100. The control device 100 can be configured to send a control signal to a control unit of the motor vehicle. The control signal can enable the activation of vehicle settings or options, such as sound or headlight controls, for example.

[0038] In general, the control device 100 can be used for any application requiring at least one setting.

[0039] The control device 100 comprises a fixed part 110, a moving part 120 and an elastic return means 130.

[0040] The elastic return means 130 is interposed between the moving part 120 and the fixed part 110. Thus, the elastic return means 130 tends to move the moving part 120 along a direction of displacement D' and in a particular direction in the absence of any other stress.

[0041] The elastic return means 130 here comprises elastomer membranes. These membranes also make it possible to define a pressure profile that is comfortable for the user when pressing on the moving part 120.

[0042] An example of a pressure profile, i.e. the force F required to be applied to the moving part 120 to generate a displacement d along the direction of displacement D' and in the opposite direction to the particular direction mentioned above, as a function of the displacement d is shown in [Fig.5].

[0043] Alternatively, the elastic return means 130 can be a spring.

[0044] The fixed part 110 here comprises a printed circuit board 113, a light source 111 and a light sensor 112.

[0045] The light source 111 and the light sensor 112 are here directly fixed to the printed circuit board 113. The light source 111 and the sensor 112 are represented as a common assembly.

[0046] The printed circuit board 113 is a flat surface extending along two perpendicular principal directions. One of the principal directions is parallel to the direction of movement D' of the moving part 120. The other principal direction is perpendicular to the direction of movement D'.

[0047] The light source 111 and the light sensor 112 are here aligned along the direction of movement D'.

[0048] The light source 111 emits a light beam having a principal direction illuminance perpendicular to the direction of movement D'.

[0049] The light source 111 is here a light-emitting diode (commonly called an LED).

[0050] The light sensor 112 is, for example, a photodiode. The light sensor 112 can be any other instrument that converts an optical signal OS into an electrical signal. The electrical signal output from the light sensor 112 is called the control signal.

[0051] The light sensor 112 includes a photosensitive surface parallel to the direction of displacement D'.

[0052] The movable part 120 can move against the elastic return means 130 between a first position and a second position according to the direction of movement D'.

[0053] The movable part 120 here comprises a hollow tubular element 125, a main plate 124 and an outer element 126.

[0054] The main plate 124 includes a reflective portion 121. The main plate 124 is fixed to the tubular element 125 by means of a clip and includes a part which closes the recessed passage formed by the tubular element 125. The main plate 124 is here in contact with the membranes of the elastic return means 130.

[0055] The main plate is here made (in one piece) of plastic material, for example by molding.

[0056] The reflective portion 121 is here formed from white plastic (the same as that of the main plate) with a high level of polishing (for example, a mirror polish). This polishing makes it possible to obtain a high reflectivity. The reflective portion 121 can, for example, have a reflectivity greater than 90%.

[0057] Alternatively, the reflective portion 121 can be a mirror or any other surface capable of reflecting light.

[0058] The reflective portion 121 is configured to reflect a beam of light from the light source 111 towards the light sensor 112 when the movable part 120 is in the first position.

[0059] The light brush is included in the light beam exiting the light source.

[0060] The reflective portion 121 is configured so as not to reflect the light beam from the light source 111 towards the light sensor 112 when the movable part 120 is in the second position.

[0061] In other words, when the moving part 120 is in the second position, the reflective portion 121 is outside the optical path.

[0062] For example, the light source 111 can generate a cone of illumination. The reflective portion 121 can be located within the cone of illumination when the movable part 120 is in the first position. Similarly, the reflective portion 121 can be located outside the cone of illumination when the movable part 120 is in the second position.

[0063] Alternatively, the reflective portion 121 can reflect rays from the light beam exiting the light source in directions other than the light sensor 112.

[0064] Some light rays may be reflected by the rest of the moving part 120 and generate a parasitic optical signal OS at the level of the light sensor 112.

[0065] Consequently, the moving part 120 here includes an aperture 122 positioned in the optical path of the light source 111 when the moving part 120 is in the second position. The aperture 122 allows light from the light source 111 to pass through, thus minimizing unwanted optical signals in the light sensor 112.

[0066] In order for the movable part 120 to be able to move without friction between the two positions, a space called an air gap is provided between the fixed part 110 and the reflective portion 121.

[0067] The movement of the moving part 120 can here be activated by the push of a user on the external element 126 of the moving part 120 in the direction of movement D' against the elastic return means.

[0068] The moving part can, for example, form a push button.

[0069] Alternatively, the displacement d could also be generated by a mechanical device.

[0070] To avoid contamination of the light sensor 112 by dust or a liquid drop, for example, the moving part 120 may include a projecting part 123 forming a protective surface above the air blade.

[0071] Here, the projecting part is included in the main plate. The projecting part 123 can emerge from the main plate 124 of the movable part 120 and extend partly into the gap formed between the fixed part 110 and the movable part 120.

[0072] This protruding part 123, covering at least partially the air gap, protects the light sensor 112 from any external contaminant.

[0073] The control device 100 is configured to send the control signal when the moving part 120 is in one of two positions. Here, the control device 100 is configured to send the control signal when the moving part 120 is in the second position.

[0074] The control signal is sent when the light sensor 112 detects a signal variation greater than a threshold variation.

[0075] In the embodiment described here, the first position is a relaxed position, that is to say that no force F is applied on the moving part 120. The control device 100 is at rest.

[0076] In this same embodiment, the second position is a supported position. That is to say, a force F is exerted on the moving part 120 along the direction of movement. The control device 100 is active and the elastic return means are in compression.

[0077] When no force F is applied to the moving part 120, the moving part 120 can automatically return to the released position by means of the elastic return means 130.

[0078] In this configuration, when the control device 100 is at rest, the light beam is reflected by the reflective portion 121 towards the light sensor 112. The optical signal OS is therefore maximum in the first position (i.e. here the released position).

[0079] When the control device 100 is active, the moving part 120 is moved along the direction of movement D', and the reflective portion 121 is therefore outside the optical path of the light source 111. The displacement d brings the aperture 122 onto the optical path of the light source 111. The light beam is then transmitted through the aperture 122 and does not reach the light sensor 112. The optical signal OS then decreases sharply when the moving part 120 is in the second position (i.e. here the pressed position).

[0080] The control device 100 then sends a control signal when it detects a drop in the optical signal OS.

[0081] Alternatively, the first position could be the pressed position and the second position could be the released position. In this case, the aperture 122 would be on the optical path of the light beam when the movable part 120 is in the released position, and the reflective portion 121, which reflects the light beam towards the light sensor 112, would be positioned on the optical path of the light beam by means of the movement of the movable part 120.

[0082] In this case, the control device 100 sends a control signal when it detects an optical OS signal and not when it detects a signal drop.

[0083] In order to adjust the threshold value Vs triggering the sending of the control signal, for example, a calibration of the control device 100 is carried out.

[0084] Calibration makes it possible to take into account in particular the variation of the sensor (the value of the nominal signal can vary from one sensor to another), the variation of the intensity of the light source 111 or even mechanical variations (the location of the components relative to each other).

[0085] To calibrate the control device 100, it is necessary to ensure that the haptic curve, that is to say the curve of the force F applied on the moving part 120, as a function of the displacement d of the moving part 120 and of which an example is illustrated in [Fig.5], is synchronized with the curve of the optical signal OS as a function of the displacement d, as represented in [Fig.6].

[0086] On the curves in Figures 5 and 6, points PO, PI, P2, and P3 allow verification of the synchronization of the two curves. At point PO, no force F is applied to the moving part 120, the displacement d is zero, and the optical signal OS is at its maximum. The control device 100 is at rest.

[0087] At point PI, the force F exerted on the moving part 120 is significant but not maximum, as shown in [Fig. 5]. The moving part 120 is not in the pressed position. The graph of curve 6 clearly shows a drop in the optical signal OS at point PI, but the value of the optical signal OS is above the threshold value Vs and does not trigger the transmission of a control signal.

[0088] At point P2, a dip in the force F exerted on the moving part 120 can be observed in [Fig. 5]. This dip allows a support position to be maintained with a pleasant user experience. [Fig. 6] shows that the optical signal OS is zero at point P2. Since the optical signal OS is then below the threshold value Vs, the control device 100 sends a control signal.

[0089] At point P3, the displacement d is maximum (as seen in [Fig.5]) and the optical signal OS is zero (as seen in [Fig.6]). The control device 100 is active.

[0090] During the calibration of the control device 100, the threshold value Vs of the optical signal is defined so as to be between the values ​​of the optical signal OS at positions PI and P2.

[0091] Since the signal can vary depending on external parameters (such as temperature or component aging, for example), it may be necessary to measure the maximum optical signal OS when the control device 100 is at rest in order to adjust the threshold value Vs that triggers the control signal. In other words, the signal considered for comparison with the threshold value Vs is a relative value with respect to the maximum value measured previously, and not an absolute value.

Claims

Demands

1. Control device (100) comprising a fixed part (110), a movable part (120) and an elastic return means (130) interposed between the movable part (120) and the fixed part (110), the movable part (120) being configured to move against the elastic return means (130) between a first position and a second position along a direction of movement (D'), the fixed part (110) comprising a light source (111) and a light sensor (112), the control device (100) being characterized in that the movable part (120) comprises a reflective portion (121) configured to reflect a beam of light from the light source (111) towards the light sensor (112) when the movable part (120) is in the first position,in that the reflective portion (121) is configured so as not to reflect said light beam towards the light sensor (112) when the movable part (120) is in the second position and in that the light source (111) and the light sensor (112) are aligned along the direction of movement (D'), the light source (111) has a principal direction of illumination perpendicular to the direction of movement (D'), and the light sensor (112) comprises a photosensitive surface parallel to the direction of movement (D').

2. Control device (100) according to claim 1, wherein the light source (111) and the light sensor (112) are fixed on a printed circuit board 113.

3. Control device (100) according to claim 2, wherein the direction of movement (D') is parallel to the printed circuit board (113).

4. Control device (100) according to any one of claims 1 to 3, wherein the control device (100) is configured to send a control signal when the moving part (120) is in one of two positions.

5. Control device (100) according to claim 4, wherein the control signal is sent when the light sensor (112) detects a signal variation greater than a threshold variation.

6. Control device (100) according to any one of claims 1 to 5, wherein the first position is a released position and the second position is a pressed position.

7. Control device (100) according to any one of claims 1 to 6, wherein the movable part (120) includes an opening (122) configured to allow light from the light source (111) to pass through when the movable part (120) is in the second position.

8. Control device (100) according to any one of claims 1 to 7, wherein the reflective portion (121) is formed by polished white plastic.

9. Control device (100) according to any one of claims 1 to 8, wherein there is an air gap between the fixed part (110) and the reflective portion (121), and wherein the movable part (120) includes a projecting part (123) configured to at least partially cover the air gap.

10. Control device (100) according to any one of claims 1 to 9, wherein the elastic return means (130) comprises elastomer membranes.

11. Automatic gearbox (200) comprising at least one control device (100) according to any one of claims 1 to 10, the control device (100) being configured to send a control signal to a control unit of a motor vehicle.

12. Steering wheel comprising at least one control device (100) according to any one of claims 1 to 10, the control device (100) being configured to send a control signal to a control unit of a motor vehicle.

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