Abstract:
The invention pertains to an onboard indicator ( 1 ) with luminous needle ( 10 ) , which indicator is mounted on a dashboard electronic card ( 21 ), the needle comprising an arm movable in rotation with a light source ( 13 ) and the card a source ( 22 ) for energizing the light source. It is characterized in that the light source comprises a support of flexible material ( 30 ) with a first part ( 30′ ) covered with a photophore substance ( 13 ) subjected to an electric voltage from the energizing source to which it is linked electrically by a flexible electrical link ( 30, 31, 32 ) formed by a second part ( 30″ ) of the insulating flexible support ( 30 ) serving as substrate for at least two conducting tracks ( 31, 32 ). 
     The solution of the invention makes it possible to produce a very flat indicator with a minimum of components.

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS 
       [0001]    The present Application is a National Stage of Application PCT/EP2004/01837 entitled, “Onboard Indicator Needle with Luminescent Lighting” filed on Jul. 13, 2004 which published under PCT Article 21(2) on Jan. 27, 2005 as WO 2005/008185 A2 in the French language, which claims priority to French Patent Application No. 03/08676 filed on Jul. 16, 2003, the disclosures of which are incorporated herein by reference in their entirety. 
       BACKGROUND 
       [0002]    The invention relates to the field of onboard indicators with luminous needles for motor vehicle dashboards and more particularly the mounting and the connection of these luminous needles. 
         [0003]    Luminous needles exist on numerous motor vehicle dashboard indicator dials. They are designed to indicate, as a function of their angular swing over a determined sector of the dial, a physical quantity relating to the vehicle. 
         [0004]    The luminous needles may, on the basis of a fixed light source close to their rotational spindle, receive their light by virtue of light guides provided in their hub and be arranged so as to diffuse the light over their length. In this case, in their rotational motion to indicate a physical quantity, the light source remains fixed and there is no problem with its electrical energizing (or ability to receive power). However, this mode of lighting requires a hub of complex design and the brightness of the needle is not optimal. 
         [0005]    Luminous needles may also contain their own light source, which is then energized electrically by conductors provided in the hub. This method eliminates the drawback above, but the electrical link between the two sources is dynamic since the light source turning with the needle and the electrical energizing source is fixed on the electronic card of the dashboard. 
         [0006]    The proposal has been contemplated, for example in U.S. Pat. No. 5,797,345, to mount sliding contacts linked to the light source on the hub of the needle and fix the contacts linked to the energizing source in contact with the sliding contacts. 
         [0007]    This second solution has the drawback however of requiring the presence of sliding contacts which may be prone to wear by friction and mishandling even to the extent of cutting off the energy supply to the light source. Additionally, the complexity of the mounting of the electrical circuits gives rise to additional cost considerations. 
       SUMMARY 
       [0008]    The present vehicle dashboard proposes, for this second solution, an improvement aimed at eliminating the presence of any sliding contact while ensuring simple mounting of the needle. 
         [0009]    In one exemplary embodiment, an onboard indicator includes a luminous needle. The indicator is mounted on a dashboard electronic card and the needle comprises an arm rotatable with a light source. The dashboard electronic card is configured to provide an energizing source for the light source and the light source comprises a support composed of flexible material having a first part and second part. The first part is covered with a photophore substance and is configured to be subjected to an electric voltage from the energizing source. The first part is linked electrically by a flexible link formed by the second part of the flexible support and wherein the second part serves as substrate for at least two conducting tracks. 
         [0010]    In another exemplary embodiment, a vehicle dashboard comprises a dashboard electronic card, an indicator mounted with respect to the dashboard electronic card, a needle mounted with respect to the indicator and configured to illuminate. The needle comprises a rotatable arm having a light source and the dashboard electronic card is configured to provide electric power to the light source. A flexible support has a first part and a second part, the first part having a photophore substrate. The first part is flexible and configured to receive an electronic voltage from the dashboard electronic card. At least two conductive tracks are coupled to the second part and the first part is configured to electrically link the second part and the dashboard electronic card. 
         [0011]    In yet another exemplary embodiment, is a method of operating a needle of an onboard indicator suitable for a dashboard of a motor vehicle. The needle rotates with respect to the dashboard. The method comprises: providing an electronic card with the electronic card coupled to the onboard indicator; providing a light source, with the light source rotatable and the electronic card configured to power the light source through at least two conductive tracks; providing an electrically conductive support with pins mounted with respect to the electronic card (the pins are configured to be in contact with at least one of the two conductive tracks); providing a flexible electrical link between the conductive tracks and the electrically conductive support; and powering the light source from the electronic card through the flexible electrical link. 
         [0012]    For this purpose, the vehicle dashboard relates to an onboard indicator with luminous needle in which indicator is mounted on a dashboard electronic card. The needle comprises an arm movable in rotation with a light source and the electronic card a source for energizing the light source. The indicator has a light source which comprises a first part of a support of flexible material covered with a photophore substance subjected to an electric voltage from the energizing source which it is linked electrically by a flexible electrical link (or flexible link) formed by a second part of the insulating flexible support. The second part of the insulating flexible support serves as substrate for at least two conducting tracks. 
         [0013]    In particular, the second part of the flexible support is attached to at least two pins so that can each be fitted into an electrical contact attached to the electronic card. Each pin is in contact with one of the two conducting tracks. 
         [0014]    When the indicator is activated (or called on to indicate a physical quantity), the needle pivots about its spindle and the electrical link unwinds around the hub of the needle. Therefore, the need for a sliding contact has been eliminated. 
         [0015]    The needle comprises a minimum of components to be mounted with the space of the vehicle dashboard. 
         [0016]    Preferably, at its end attached to the electronic card, the flexible film is attached to at least two pins that each can be fitted into an electrical contact on the electronic card. Each pin is in contact with one or other of the two conducting tracks. 
         [0017]    This arrangement allows mounting of the indicator in a single operation by plugging in the electrical connections of the light source into the needle with the energy supply. 
         [0018]    Advantageously, the pins are assembled on a support of pins which can be secured into a housing thereby retaining the support provided in the needle to facilitate mounting. 
         [0019]    Advantageously, the pins support retaining housing and the electrical contacts of the electronic card are arranged so as to enable the pins to be plugged into the contacts in the mounted position of the indicator. To avoid the colliding of the housing for retaining the pins support with the pins support the indicator is positioned not to block the operation thereof or hinder the swing of the indicator during operation. 
         [0020]    Advantageously still, the pins support and the retaining housing are arranged so as to be detached upon the powering-up of the motor of the indicator. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0021]    The invention will be better understood by virtue of the following description of exemplary embodiments of an onboard indicator and of the accompanying drawings: 
           [0022]      FIG. 1  represents a sectional profile view of the needle of the onboard indicator according to one exemplary embodiment of the vehicle dashboard. 
           [0023]      FIG. 2  represents a view from below of the needle in the same position, the electronic card and the dial being removed, according to one exemplary embodiment of the vehicle dashboard; 
           [0024]      FIG. 3  represents a perspective view of the pins support according to one exemplary embodiment of the vehicle dashboard; 
           [0025]      FIG. 4  represents a sectional profile view of the needle of the onboard indicator of the vehicle dashboard, according to one exemplary embodiment of the vehicle dashboard; and 
           [0026]      FIG. 5  represents a view from below of the needle in the same position as  FIG. 4  according to one exemplary embodiment of the vehicle dashboard. 
       
    
    
     DETAILED DESCRIPTION  
       [0027]    With reference to  FIG. 1 , the onboard indicator  1  of the vehicle dashboard comprises a dial  14 , made of polycarbonate materials for example, bearing graduations indicative of physical quantities relating to the progress of the vehicle. In the centre of the onboard indicator an opening  40  (or orifice) is defined through which there passes a hub  15  attached to a spindle  19  of a motor  20 . The motor may be a stepper motor for example mounted on an electronic card  21 . 
         [0028]    The hub  15  is extended by a needle  10  running towards the graduations of the dial  14  through an arm  11  which is at least partially covered by a transparent fairing  12  (or smooth surface). The stepper motor  20  is arranged so as to make the needle pivot as a function of the physical quantity to be displayed on the dial. 
         [0029]    An adhesive is utilized between the visible part of the arm  11  and the fairing  12  and applied onto the arm in which case a first part  30 ′ of a support is partially covered with a layer of photophore material. In one exemplary embodiment the material is an electroluminescent ink applied over a determined area so as to form the pointer of the needle. 
         [0030]    According to an exemplary embodiment of the onboard indicator  1  includes a support  30  which runs beyond the arm  11  of the needle  10  through a second band-shaped part  30 ″ extending along the hub  15 . The support  30  is free to pass through the dial  14  via the opening  40  and travel around the hub  15  along an ‘S’ shaped spiral surrounding the hub underneath the dial. To accomplish this, the support  30  is folded over on itself at 90° at approximately the height of the hub, forming a fold  45 . 
         [0031]    The support  30  is electrically insulating. The second part of the support comprises two parallel conducting tracks  31  and  32  linked to either side of the pointer so as to energize it electrically in a suitable manner and to enable the pointer to extend without interruption up to its free end. On the first part  30 ′ of the support  30  these two conducting tracks act as electrodes over the entire length of the needle or at least its visible part and enables the excitation of the electroluminescent ink. One of the tracks  31  abuts contact  41  with a pin  23  attached to the support  30 , and the other track  32  abuts contact  42  with another pin  24  which is also attached to the support  30 . The contacts  41  and  42  are fairly distant from the support  30  so as to provide for mounting. In one exemplary embodiment, as illustrated in  FIG. 2 , the ‘S’ shaped spiral is formed by the band  30 ″ around the hub  15  and the layout of the pins ( 23  and  24 ) attached to its free end. As the band  30 ″ is flexible, the pins  23 ,  24  are held in parallel with respect to one another by means of a pins support  25 , as is illustrated in  FIG. 3 . 
         [0032]    The pin support  25  comprises a central spigot  26 , and two equidistant holes (or apertures)  43  and  44  in which the ends  33  and  34  of the pins  23  and  24  are inserted. The pins  23 ,  24  run out of the support  25  away from the central spigot  26 . 
         [0033]    The band  30 ″ is glued to the pins  23  and  24 . In one exemplary embodiment, in order to avoid an electrical short-circuit, insulating bushings  51  and  52  have been disposed on the pins  23  and  24  to insulate the pin  23  from the track  32  and to insulate pin  24  from the track  31 . Thus the pin  23  is in electrical contact at  41  only with the track  31  and the pin  24  is in electrical contact at  42  only with the track  32 . 
         [0034]    Under the needle  10 , a spigot  16  has been provided in such a way as to be fairly close to the hub  15  so as to pass into the opening  40  in which a housing  17  retaining the support  25  of the pins  23  and  24  has been made. 
         [0035]    The spigot  16  of the needle  10  is of such a length that when the spigot  26  of the pin support  25  is engaged in the housing  17  the pins  23  and  24  can be plugged into the electrical contacts  22  attached to the electronic card  21 . The housing  17  is arranged, as in  FIG. 5 , so as to retain the spigot  26  by lateral snap-fastening. 
         [0036]    When in a mounted position of the needle, the spigots  16  and  26  are aligned and the pins are plugged into the contacts  22 , the needle is situated outside of its operating range on the dial. Consequently, the length of the band  30 ″ is sufficient to allow the needle to pivot not only over the entirety of the operating range, but also beyond the mounted position of the needle. 
         [0037]    During normal operation of the indicator  1 , as illustrated in the exemplary embodiment of  FIG. 4 , the needle  10  is in an operating position situated somewhere in a sector determined by its swing about its spindle  19 . In general, the swing covers an angle of 180° or more. In this case, the support  25  of the pins  23 ,  24 , which are plugged into the contacts  22 , is not situated in the sector. The support  25  remains out of reach of the spigot  16  of the needle  10  thereby not hindered in its motion. 
         [0038]    For the mounting of the needle, the spigot  26  of the support  25  of the pins  23 ,  24  is engaged into the housing  17  and the pins are plugged into the contacts  22  . Simultaneously the hub  15  is plugged into the spindle  19  of the motor  20 . The needle is then placed in a mounted position as in  FIG. 1 , outside of the sector determined by its sweep while operating. 
         [0039]    For placement in the operating position, the needle  10  is forced, to turn, manually or automatically by starting up the motor  20 , so as to bring the needle into the sector. Through this action, the spigot  26  is forced to leave the spigot  16 . 
         [0040]    During operation, the electrodes of the first part  30 ′ of the support provide for the excitation of the photophore material which becomes luminous. Regardless of the position of the needle, the energizing of the first part is provided for by the electrodes on the second part which by virtue of the flexibility of the support  30 ″ follow the motion thereof while remaining connected to the source. 
         [0041]    It should be understood that the construction and arrangement of the elements of the onboard indicator in the exemplary embodiments are illustrative only. Although several embodiments of the onboard indicator have been described in detail in this disclosure, many modifications are possible without materially departing from the novel teachings and advantages of the subject matter recited in the claims. Accordingly, all such modifications are intended to be included within the scope of the present onboard indicator as defined in the appended claims. Unless specifically otherwise noted, the claims reciting a single particular element also encompass a plurality of such particular elements. Moreover, claims reciting that one element is coupled to another should be interpreted to mean that the elements are selectively coupled to each other and may be uncoupled or disconnected at a ny point. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. In the claims, any means-plus-function clause is intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. Other substitutions, modifications, changes and/or omissions may be made in the design, operating conditions and arrangement of the preferred and other exemplary embodiments without departing from the spirit of the present invention as expressed in the appended claims.