FR2767754A3 - CONTROL UNIT FOR PARTICULARLY A VEHICLE COMPONENT - Google Patents

Abstract

The unit has a panel (12), a control button (18) movable therein with front wall (48) and side wall (54) projecting from its rear face. Behind the panel (12) is arranged a plate (24) with for each control key (18) a light source of search lighting (30) for a symbol panel (50), and a light source of function (32 ) for the function display element (52) of the control button (18). Between the plate (24) and the panel (12) is arranged a switching mat having a base (38) provided with recesses (44) associated with each button for the two light sources (30, 32). The base (38) has, for each key, a light masking rib (72) between the two recesses (44, 46), associated with the key and overlapping the free end (74) of the light masking wall (56 ) and parallel to it.

Description

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  The invention relates to a control unit, in particular for a vehicle component, such as for example a control device.

  control of a vehicle air conditioning system.

  To be able to control a device, an installation or the like, a control unit is required which has several keys

  command to set parameters and operating modes.

  In order to be able to recognize the parameters or the operating modes that can be adjusted with the control buttons, even in the dark or in a dimly lit environment, it is advantageous for the control buttons to have symbol panels capable of being lit by the back. For a multitude of applications, it is also advisable to display via a display element of each control (function) key if the function that can be activated with this control key is switched on or off. To such a control key are therefore associated two light sources whose light must be mutually masked so that the display element and the panel

  symbol are optically decoupled.

  Optical decoupling is relatively simple to carry out when the light sources of a control key are arranged in different planes. This is for example then the case when the light source for the function display element is on the plate. The use of discrete switches is however very expensive, which is why the manufacturing costs are all the higher for a control unit having a multitude

control elements.

  The manufacturing costs for a control unit can be reduced if a flexible switching mat is used as switches which has push elements connected by a sheet, which are associated with the individual control keys and can be recalled. The switching mat rests with its base on a plate which has for each push element a pair of

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  switch contact surfaces to be electrically bridged. The pusher elements are coated with a conductive material so that the switching contact surfaces are electrically connected

  when these are contacted by the associated push element.

  The use of a switching mat, however, implies that the two light sources associated with a control key with search lighting and optical lighting for switching on the functions, are arranged in a common plane, namely on the plate. Here, there is a risk that part of the light from the search light source for the illumination from the rear of the symbol panel falls on the extinguished lamp of the button function display element. and vice versa. This risk is all the greater if one uses as light sources 1 5 light-emitting diodes mounted on the surface which are easy to mount, which moreover, because of their large angle of radiation of approximately are advantageous from the point of view of an illumination of the symbol panel and the display element over a relatively large area. The invention aims to create a control unit, in particular for a vehicle component, and preferably for the control device of a vehicle air conditioning installation which, while illuminating the symbol panel and the function display element, has sufficient reciprocal masking of

  the light from the two light sources.

  To achieve this objective, a control unit is proposed according to the invention, in particular for a vehicle component, such as for example a control device for a vehicle air conditioning installation comprising - a front panel, - at least one button. control unit movable in the front panel, which has a front wall with front and rear faces and a peripheral side wall projecting from the rear face of the front wall, the front wall having a

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  symbol panel capable of being illuminated from the rear and a function display element visualizing from an optical point of view the activation of a function capable of being switched on and off by the control button, and a light masking wall connected to the side wall projecting from the rear face of the front wall between the symbol panel and the function display element, the side wall and the light masking wall each having a free end diverted from the front wall, a plate arranged behind the front panel, which has, for each control key, a search light source for illuminating the symbol panel from behind, a function light source for the function display element and at least one pair of switching contact surfaces for making an electrical connection each time the keys are pressed mmande, and - a flexible plastic switching mat arranged between the plate and the front panel, the switching mat having a base resting on the plate, which is provided with recesses associated with each control button for the light source d search lighting and for the light source of functional lighting and provided with at least one pushing element capable of being recalled, also associated with each control key, for contacting said

  at least one pair of switching contact surfaces.

  This control unit is characterized according to the invention in that: the base of the switching mat has, for each control key, a first projecting rib for masking light, which extends between the two recesses of the base, associated at the control button, overlapping the free end, diverted from the front wall, from the light masking wall of the

  control and being parallel to the light masking wall.

  The control unit according to the invention is provided with a front panel on which several control keys are arranged mobile and guided, at least one of the control keys having

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  also, in addition to a symbol panel capable of being lit from behind, a display element which displays whether the function which can be selected with the control key is switched on or off. The symbol panel and the function display element are arranged in the front wall of the cap-shaped control button which has a peripheral side wall projecting from the front wall. The switching function of this at least one control key is carried out by means of a switching mat which is made of an elastic plastic material and which has a sheet as well as push elements which are capable of being recalled and which are flexibly connected to the base. The switching mat is located on a plate which has pairs of switching contact surfaces associated with the push elements. Due to their elastic connection on the sheet, the pusher elements can be moved in the direction of the plate, which occurs by pressing the control keys. On their ends opposite to the plate, the pusher elements are coated with an electrically conductive material or provided with a conductive contact pad and ensure electrical bridging of the switching contact surfaces when these ends of the pusher elements

  come into contact with the switching contact surfaces.

  To illuminate the symbol panel of the control keys as well as of the function display element, light sources are provided in the form of light-emitting diodes with surface-mounted components which are arranged on the plate. Since the switching mat rests on the plate, it has two recesses for each control button in which the light sources are located. For the optical appearance of the front panel and in particular for the rear lighting of control buttons fitted with a symbol or a function display element, it is important that the light source associated with the symbol does not does not radiate into the function display element and vice versa. For this reason, this control button of the control unit according to the invention is provided with a light masking wall which, like the side wall, protrudes from the front wall of the control button and is connected to the side wall. In order to improve the reciprocal masking of the light of the symbol panel and of the function display element, it is provided according to the invention that the switching mat has for each control key provided with a symbol or a function display element (hereinafter called function key) a first protruding light masking rib, which is arranged between the two recesses of the base associated with this control key and extends overlapping the end free, diverted from the front wall, from the light masking wall of the control button as well as parallel to the light masking wall of the control button. The first light masking rib of the base is therefore offset laterally with respect to the light masking wall of the associated function key, so that its penetration is not hampered by the first light masking rib. The first light masking rib and the overlapping light masking wall in each key position ensure that diffuse light from, for example, the light source associated with the symbol panel does not reach the region of the element function display button

  function control and vice versa.

  In the case of the control unit according to the invention, the switching function of the control keys is advantageously carried out, from the cost point of view, thanks to a flexible switching mat, as is known from a multitude of electronic keyboard devices. It is ensured according to the invention that in the case of control buttons with optical feedback, when the selected function is activated, to obtain an optical decoupling of the symbol panel and of the function display element by providing the ribs light masking base and the light masking walls of the control keys, which cooperate with each other and overlap at their respective free ends in each position

of the button.

  To advantageously improve the invention, it is provided that the base of the switching mat has, for each function key, in addition to the first light masking rib, a

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  second light masking rib. This second light masking rib is connected (preferably in one piece) to the first light masking rib and extends relative thereto at an acute angle, in particular at a right angle. The second light masking rib is arranged so that it overlaps the free end of the side wall of the associated function key. Both the first light masking rib and the second light masking rib extend here on the interior faces oriented towards the symbol panel of the light wall.

  hiding light and the side wall of the function key.

  The two light masking ribs provide a barrier to

  screw light, L-shaped top view, which prevents that according to the arrangement of the recesses of light sources in the bases of the switching mat of direct or reflected diffuse light from a light source does not reach the function display element or on the symbol panel, respectively, which is associated with another light source. By providing this second light masking rib, the light masking is further improved, which is particularly important when the light sources are

  arranged in different rows on the plate.

  The light masking is further improved by the fact that the base of the switching mat has a third light masking rib which is parallel to the second light masking rib and which, like this one, is connected (d 'one piece) at the first light masking rib. The three light masking ribs together form a U-shaped light barrier which extends along three sides of the base recess for the light source associated with the light symbol panel. the function key. Like the other two light masking ribs, the third light masking rib also overlaps the side wall protruding from the front wall of the function key. The three light masking ribs are all arranged in the region of the function key which is delimited by

  the side wall and through the light masking wall.

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  As mentioned above, the control keys are guided movable on the front panel. The control keys are in particular lift keys which can be moved vertically relative to the plate. In addition to or in place of such lifting keys, the front panel can also have control keys in the form of rocking keys. All the control keys are arranged inside recesses of the front panel, these recesses being delimited by an edge parallel to the side wall of the control key. The edge itself protrudes from the front panel towards the plate and is made peripheral. The edge is used on the one hand for mechanical guidance of the control button and on the other hand also for light masking. To facilitate the handling of the front panel equipped with the control keys during assembly of the control unit according to the invention, it is advisable for the control keys to be provided on the front panel so as not to unexpectedly exit from the recesses. For this purpose, the front panel has for each control key a retaining tab oriented from the edge of its respective recess towards the plate, which is provided with a retaining lug. Each control button has a recess in which the retaining tab is located when the control button is mounted on the front panel. Inside the side wall of the control button is a retaining cavity for receiving the tongue retaining element. By the cooperation between the tongue retaining element and the retaining cavity, the control key is ensured

  towards an unexpected detachment outside the front panel.

  To prevent diffuse light from escaping from the interstices between the side walls of the control button and the edges of the front panel defining the recesses, it is advantageous that the recesses of the front panel are slightly smaller than the region bounded by the edges associated with the recesses, so that a flange defining the recess is obtained, which prevents the light from coming out

  through the gap between the control button and the front panel.

  However, in order to keep the costs for the tooling for manufacturing the front panel as low as possible, with regard to the fixing described above of the control keys on the panel

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  front by means of retaining tabs and retaining lugs which engage in recess retaining cavities formed in the side walls of the control keys, it is advisable that the tabs

  retainers protrude directly from the edge of the recess.

  In this case, to manufacture the front panel by injection molding, in fact no injection mold is required with slides or the like. However, in the recess region in the side wall of each control button, a direct, albeit narrow, passage is formed from the front face of the front panel to the plate arranged behind it, so that diffuse light may escape. To avoid this, a preferred embodiment of the invention provides for extending the side wall of each control key in the region of its hollow, so that a protruding region is formed. This protruding region cooperates with a protruding region receiving recess made in the sheet of the switching mat in which it is immersed. Alternatively, it is sufficient for the base of the switching mat to have raised light masking edges which are laterally supported on the regions projecting from the side walls of the control buttons and which are arranged to overlap therewith. The fact of providing a recess for receiving the protruding region in the base of the switching mat has the advantage that the structural height of the control unit is reduced since the front panel and the plate can now be assembled closer one from the other, since the region beyond a control key can sink into the recess in the base of the switching mat

  arranged on the board when this button is pressed.

  It is further provided, as an advantageous improvement of the invention, in the region between the side wall and the light masking wall of a function key, in which the function display element is located, of arranging a fiber optic element which preferably terminates in the front wall of the function key so that its light output end which is arranged therein forms the function display element. The light entry end of the fiber optic element is arranged opposite the light source for the function lighting and is made in

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  particular in the form of an optical element, for example spherical and by

  therefore in the form of a convex lens.

  An exemplary embodiment of the invention will be explained below using the figures. These show figure 1 the front view on a front panel of a control device for a vehicle air conditioning installation, figure 2 a top view on the plate arranged behind the panel

  front shown in figure 1, with switching mat placed on it

  Ci, partially cut away, and Figures 3 and 4, sections along lines III-III and V-V of Figures 1 and 2. In Figure 1 is shown a top view on a unit of

  control 10 for a vehicle air conditioning installation.

  The control unit 10 has a front panel 12 with a front wall 14 in which a multitude of recesses 16 are made for control keys 18 and a recess 20 for a display 22. Behind the front panel 12 is a plate 24 on which rests a switching mat 26 of elastic plastic, in particular silicone rubber. The plate 24 is provided with various electronic components, for example an integrated circuit 28 for controlling the display 22 as well as a multitude of first and second light-emitting diodes 30, 32. The plate 24 also has a multitude of pairs contacts

  switching 34. which each include two contact surfaces 36.

  The switching mat 26 is constituted by a base section 38 with push elements 40 flexibly connected thereto, which are elastically movable connected with the base section 38. In their initial position, the push elements 40 have a distance from the plate 24. When a force acts on the pusher elements in the direction of the plate, the pusher elements 40 can be brought into contact with the plate 24. Since the pairs of switching contacts 34 are arranged in face of the push elements 40 and that these are provided with an electrically conductive coating 42 on their ends opposite to the plate 24 i2767754 (see FIG. 3), the switching contact surfaces 36 of the pairs of switching contacts 34 are short circulated when the push elements 40 come to bear on the pairs of switching contacts 34, so that a switching pulse occurs ion. The base 38 of the switching mat 26 also has first recesses 44 in which the first light sources 30 of the plate 24 rest freely, and second recesses 46 in

  which the second light sources 32 rest freely.

  As seen in the representations of Figures 1, 3 and 4, each control button has a front wall 48 on which is formed a symbol panel 50 which is capable of being lit from the rear. Out of the front wall, one or more actuating lugs 51 protrude, which are supported on one or more push elements 40 of the switching mat, associated with the corresponding control key 18, and which press against the plate 24 when presses the control key 18. The first light source 30 (light source for lighting the symbol panel) is used to back light the symbol panel 40 of each control key. In addition to the symbol panel 50, some of the control keys 18 have in their front wall 46 a function display element 52 which displays from an optical point of view whether the function, capable of being activated by the corresponding control 18 of the device presenting the control unit, is switched on or off. The second light sources 32 (light sources for lighting the function display) serve to illuminate the function display elements 52 of the control keys 18 (insofar as these have such display elements of

functions).

  The control keys 18 provided with function display elements 52 (hereinafter called function keys) have a peripheral lateral edge 54 which projects from the front wall 48 up to the plate 24. In the region between the panel symbol and the function display element 52, each function key is provided with a light masking wall 56 which projects from the front wall 48 of the control key 18 as far as towards

  the plate 24 and which is connected in one piece with the lateral edge 54.

  The purpose of the light masking wall 56 is to prevent light from the light source 30 provided for illumination from the back of the symbol panel from a function key 18 from reaching the element function display 52. Likewise, the light masking wall 56 of a function key 18 prevents light from the light source 32 for lighting the function display from reaching the symbol panel 50 of the function key 18. The light sources 30 and 32 are surface mount light emitting diodes which have a relatively large radiation angle of approximately 120. Such light-emitting diodes make it all the more necessary to ensure reciprocal light masking of the symbol panels 50 and of the

  function display elements 52 of the function keys.

  As seen in particular in Figure 3, there are in the parts of the function keys 18 in which the function display elements are arranged, fiber optic elements 58 which have a light input end 60 spherical oriented towards the light sources 32 for lighting the function elements and a light output end 62, said fiber elements

  optics forming the function display elements 52.

  As explained above, the control keys 18 are produced in the form of linear displacement keys which are guided movably in the recesses 16 of the front panel 12. For this purpose, the front panel 12 has peripheral walls 64 starting from their front wall. 14, oriented towards the plate 24 and extending up to the sheet 38 of the switching mat 26, said walls 64 being provided for each recess 16. Between the recesses 16 and the walls 64 are flanges which cooperate with flanges 68 corresponding to the side edges 54 of the control keys 18. Thanks to these flanges 66, 68, it is prevented that the control keys 18 do not fall out of the front panel 12. In addition, the flanges 66, 68 ensure tracing by

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  Z-shaped section of the slot 70 between the side walls 54 of the control keys 18 and the walls 64 of the front panel 12, so that diffuse light cannot reach through the slot 70

  up to the front of the front panel 12.

  As seen in particular in Figure 2, light masking ribs protruding from the base 48 of the switching mat extend around the recesses 44 for the light sources 30 for lighting the symbol panels. First light masking ribs 72 here extend between a first and a respective second recess 44, 46, the height of which is such that they protrude above the free ends 74 of the light masking walls 56 when the function keys are not pressed (see Figure 3). Second and third light masking ribs 76, 78 extend parallel to each other and transversely to the first light masking ribs 72, with the ends of which they are connected. These second and these third light masking ribs 76, 78 extend beyond the free ends 80, oriented towards the plate 24, from the lateral edges 54

  function keys 18, which is shown in particular in FIG. 4.

  All these light masking ribs 72, 76 and 78 are arranged and dimensioned so that they are arranged inside the part of the switching mat 26 which is opposite to the symbol panel 50 of a function key. 18. In other words, for each function key 18, its lateral edge 54 as well as the light masking wall 56 are located outside the

  region defined by the light masking ribs 72, 76 and 78.

  Thanks to the light masking ribs 72, 76 and 78, the co-operation between the lateral edges 54 and the light masking walls 56 of the control keys 18 gives optimum masking of the light from the light-emitting diodes mounted in surface 30 and 32, so that the incidence of diffuse light is avoided in regions of the control keys 18 which are not respectively associated with these light sources. Thanks to this, the symbol panels 50 and the function display elements 52 of the control keys 18

  are optically decoupled.

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  As seen in particular using FIG. 4, the control keys 18, to prevent them from sliding out of the front panel 12, are provided on their rear face, before and during assembly, by tongues retaining 82 elastic with snap lugs 84 which are immersed in grooves 86 of the side walls 54 of the control keys 18. These grooves 86 terminate at a distance from the front wall 48 of the control keys 18, so that at level of the reference number 88 is formed a stop cooperating with the retaining lugs 84. For reasons of simplification of the structure of the plastic injection molding tool, used for the manufacture of the front panel 12, the retaining tabs 84 are aligned with the edges of the recesses 16. Thanks to this, a slit 90 is obtained in this region up to the switching mat 26, through which the diffuse light can escape from the front panel 12. To avoid this, each side wall 52 has in the region of its groove 86 a protruding region 92 beyond the free end 80, which plunges into a recess 94 in the base 38 of the switching mat 26. These recesses 94 receiving the protruding region have raised light masking edges 96 on both sides and are aligned with

  the light masking ribs 76 of the switching mat 26.

  By virtue of the extension of the lateral edges 54 of the control keys 18 in the region of their grooves 86 and thanks to the production of the recesses 94 for receiving the region beyond the switching mat 26, it is prevented that diffuse light reaches into the ends oriented towards the switching mat 26, front grooves 86 open, so that diffuse light can not escape from the front panel 12 in the

slot region 90.

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  List of reference numbers control unit 12 front panel 14 front wall 16 recesses for the control keys 18 control keys recess for the display panel 22 display panel 24 circuit board 26 switching mat 28 integrated circuit light source for the lighting from the back of the symbol panel 1 5 32 light source for lighting the function display 34 pair of switching contacts 36 switching contact surfaces 38 base of the switching mat push elements 42 coating of the push elements 44 first recesses 46 second recesses 48 front wall of the control keys symbol panel 51 actuating lug 52 function display element 54 side edge 56 light masking wall 58 fiber optic element 60 spherical entry end of the light

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  62 light outlet end of the fiber optic element 64 wall 66 flange in the wall 68 flange in the side wall 70 slot between control button and recess for the display panel 72 first light masking rib 74 free end of the light masking wall 76 second light masking rib 78 third light masking rib free end of the lateral edge 82 retaining tab 84 retaining lug 86 groove in the lateral edge 88 stop in the groove slot 92 protruding region 94 recess in the sheet to receive the protruding region 96 light masking edges on both sides of the recess

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Claims (11)

Claims   1. Control unit, in particular for a vehicle component, such as for example a control device for a vehicle air conditioning installation comprising - a front panel (12), - at least one control button (18) arranged movable in the front panel (12), which has a front wall (48) with front and rear face and a peripheral side wall (54) projecting with respect to the rear face of the front wall (48), the front wall ( 48) having a symbol panel (50) capable of being lit from the rear and a function display element visualizing from an optical point of view the activation of a function capable of being switched on and off by the control button (18), and a light masking wall connected to the side wall (54) projecting from the rear face of the front wall (48) between the symbol panel (50) and the element d 'function display (52), the side wall (54) and the light masking wall (56) each having a free end (74, 80) diverted from the front wall (48), - a plate (24) arranged behind the front panel (12), which has, for each control key (18), a search light source (30) for back lighting the symbol panel (50), a function light source (32) for the display element function (52) and at least one pair (34) of switching contact surfaces (36) for making an electrical connection each time the control keys are actuated, and - a switching mat (26) made of flexible plastic material arranged between the plate (24) and the front panel (12), the switching mat (26) having a base (38) resting on the plate (24), which is provided with recesses (44) associated with each control key ( 18) for the search light source (30) and for the light source function lighting (32) and provided with at least one push-back element (40) capable of being recalled, also associated with each control key (18), for contacting said at least one pair (34) of surfaces switch contact (36), characterized in that the base (38) of the switch mat (26) has for each control button (18) a first protruding light masking rib (72) which extends between the two recesses (44, 46) of the base (38), associated with the control button (18), overlapping the free end (74), diverted from the front wall (48), from the masking wall light (56) of the control button (18), and   being parallel to the light masking wall (56).   2. Control unit according to claim 1, characterized in that the base (38) of the switching mat (26) has for each control button (18) a second light masking rib (76) which is connected to the first light masking rib (72) and which is arranged by overlapping the free end (80), diverted from the front wall (48), from the side wall (54) of the control button (18). 3. Control unit according to claim 2, characterized in that the base (38) of the switching mat (26) has for each control button (18) a third light masking rib (78) which is connected to the second light masking rib (76) and which is arranged by overlapping the free end (80), diverted from the front wall (48), from the side wall (54) of the control button (18).   4. Control unit according to any one of claims 1 to 3,   characterized in that the front panel (12) has for each control button (18) a recess (16) with an edge (64) parallel to the side wall (54) and in that a retaining tab (82) elastic oriented towards the plate (24) protrudes out of the recess (16) with a retaining lug (84) and in that the side wall (54) of the control button (18) has a recess (86) receiving the retaining lug (84).   5. Control unit according to claim 4, characterized in that the side wall (54) has in the region of its hollow (84) a protruding region (92) and in that the base (38) of the switching mat (26) has for each control key (18) a receiving recess (94) of protruding region for receiving the protruding region (92) of the side wall (54) of the control (18).   6. Control unit according to claim 5, characterized in that the base (38) of the switching mat (26) has locally for each receiving recess (94) of the protruding region a raised light masking edge (96) which is in alignment with the edge of the receiving recess (94) of the protruding region and which   overlaps the protruding region (92) of the side wall (54).   7. Control unit according to claim 5, characterized in that the base (38) of the switching mat (26) has, for each protruding region (92) of the side wall of the control keys (18), edges masking light (96) raised which each overlap the protruding regions (92) of the side walls of the control buttons (18).   8. Control unit according to claim 7, characterized in that the light masking edges (96) are in alignment with the edges of the receiving recesses (94) of the region projecting from the base (38) of the switching mat. (26), the receiving recesses (94) of the protruding region being in alignment with the regions of   protrusion (92) of the side walls (54) of the control keys (18).   9. control unit according to claims 2 and 6 or 2 and 8,   characterized in that for each control key (18), the second light masking rib (76) is arranged between the recess (44) of the base (38) of the switching mat (26) for the light source d search lighting (30) and the receiving recesses (94) of the region projecting from the base (38) of the switching mat (26) and is locally in alignment with the edge of the   receiving recesses (94) of the overshoot region.   10. Control unit according to any one of claims 1 to   9, characterized in that each control key (18) provided with a function display element (52) has a fiber optic element (58) whose light entry end (60) is diverted from the front wall (48) of the control button (18) and whose light output end (62) faces the function display element (52) and in particular forms the element function display.   11. Control unit according to any one of claims 1 to   , characterized in that the light sources (30, 32) for search and functional lighting are each produced from   light-emitting diodes of the surface-mounted component type.