Patent Publication Number: US-7591573-B2

Title: Headlight lamp holder equipped with claws oriented tangentially with respect to the wall of the lamp holder

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The invention concerns a headlight lamp holder, in particular for a motor vehicle, which is intended to carry a lamp, the cap of which is connected to a high-voltage connector. 
   2. Description of the Related Art 
   In headlights using a high-voltage lamp, the lamp emits an electromagnetic field that charges the reflector of the headlight with static electricity, increasing its electrical potential. In order to prevent the electrical potential increasing too much and causing sparks, the reflector must be electrically connected to the vehicle earth. 
   For this purpose, the lamp holder is produced from an electrically conductive material. The lamp holder is then electrically connected to the body of the high-voltage connector of the lamp, which is itself electrically connected to the vehicle earth. To electrically connect the lamp holder to the body of the connector of the lamp, equipping the lamp holder with contact claws is known. 
   Lamp holders of this type are already known. The lamp holder is generally equipped with claws that extend longitudinally towards the rear, projecting with respect to the rear end edge of the lamp holder. The claws thus extend in a ring over at least three quarters of the circumference of the rear end edge. 
   For their fixing to the lamp holder, the claws are generally produced in one piece with a clamping collar that is clamped around the external cylindrical wall of the lamp holder. This operation of clamping the claws on the lamp holder constitutes an additional operation in the assembly process, time-consuming, expensive, and liable to give rise to rejects. 
   However, such a design makes it difficult to mount the lamp on the lamp holder. This is because, in this arrangement, the claws partially block the rear orifice of the lamp holder in which the lamp must be inserted. It is in particular necessary to separate the claws in order to separate the lamp, and then actuate the means of fixing the lamp in the lamp holder. This operation requires in particular for the operator to be able to have access visually to the lamp holder in order to guide his actions. 
   In addition, in this arrangement, the size of the claws towards the rear is liable to pose problems for arranging the lamp holder in the engine. 
   In addition, the bayonet fixing of the connector on the lamp, and in particular the pivoting movement about the principal axis of the lamp holder, requires a relatively high force because the claws rub on the external wall of the body of the connector without being able to move away automatically. 
   What is needed therefore, is a lamp holder that overcomes one or more of the aforementioned problems. 
   SUMMARY OF THE INVENTION 
   The invention therefore proposes to resolve these problems by proposing a lamp holder of the type described above, wherein the claw extends in a tangential direction with respect of the lamp holder and perpendicular with respect to the longitudinal principal axis. 
   The invention concerns more particularly a lamp holder for a headlight, in particular for a motor vehicle, which is intended to carry a lamp whose cap comprises means for the bayonet mounting of a high-voltage connector, the lamp holder comprising:
         a body delimited radially by a roughly cylindrical tubular wall with a longitudinal principal axis, produced from an electrically conductive material;   means of fixing the cap of the lamp coaxially in the lamp holder so that the body of the high-voltage connector, when it is mounted on the lamp, extends longitudinally towards the rear from a rear end edge of the wall of the lamp holder;   at least once claw electrically connected to the wall of the lamp holder and intended to be in contact with the body of the high-voltage connector, when it is mounted, so as to discharge the lamp holder, which is electrically charged by an electromagnetic field emitted by the lamp.       

   According to other characteristics of the invention:
         the claw is carried by a rear end portion of a longitudinal finger that is fixed to an external face of the wall of the lamp holder and extends projecting with respect to the rear end edge of the wall of the lamp holder;   the claw extends from the finger in a tangential direction with respect to the wall of the lamp holder in the direction of the pivoting movement for the bayonet mounting of the high-voltage connector;   the lamp holder has a plurality of claws that are carried by at least one finger;   the claws are arranged on the rear end portion of the finger, longitudinally one behind the other and parallel to each other so as to form a comb;   the claws are elastically deformable in flexion in a radial direction with respect to the principal axis of the lamp holder;   the finger is fixed to the wall of the lamp holder by means of a fixing flange;   the finger is fixed to the wall of the lamp holder by a elastic snapping of the front end portion of the finger in a housing of complementary shape;   the housing is formed by at least one carrier arranged on the external cylindrical face of the lamp holder so that the front end portion of the finger is mounted in a longitudinal sliding movement from rear to front between the external cylindrical face of the lamp holder and the carrier;   the front end portion of the finger comprises a lug that extends radially so as to be received by elastic deformation in an associated aperture carried by the wall of the lamp holder in order to lock the sliding of the finger towards the rear;   the aperture is carried by the carrier;   the front end portion of the finger has a radial shoulder face intended to be in contact with an opposite face of the carrier in order to lock the sliding of the finger towards the front;   the lamp holder is of the type in which the lamp is intended to be introduced from rear to front coaxially with the wall of the lamp holder until the cap is in abutment against a radial shoulder face of the lamp holder, and of the type in which the means of fixing the lamp cap comprise two parallel arms that extend in a radial plane inside the lamp holder and that are mounted so as to pivot about a common transverse axis arranged substantially tangentially to the wall of the lamp holder, between a front position and a rear position, the arms being mounted so as to be articulated with respect to the pivot axis between a first closed position in which the three ends of the arms are close to each other and a second open position in which the free ends of the arms are separated from each other, towards which they are elastically returned so that, in a closed front locking position, the arms lock the cap of the lamp against the shoulder face of the lamp holder, and so that, in a rear open release position, the cap is able to slide longitudinally towards the rear, the rotation of the arms about the pivot axis towards the rear being limited by a stop, wherein the stop is produced in one piece with the wall of the lamp holder;   the stop is produced by the rear lip of an opening produced in the cylindrical wall of the lamp holder;   the opening is produced in the vicinity of the free end of the arms;   the common pivot axis is produced in one piece with the arms.       

   Other characteristics and advantages will emerge during a reading of the following detailed description, for an understanding of which reference will be made to the accompanying drawings, amongst which: 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an exploded perspective view that depicts a motor vehicle headlight comprising a reflector and a lamp holder produced in accordance with the teachings of the invention, in which a lamp equipped with a high-voltage connector is mounted; 
       FIG. 2  is a detail view to a larger scale that depicts a finger of the lamp holder of  FIG. 1  carrying claws; 
       FIG. 3  is a view in perspective that depicts the lamp holder of  FIG. 1  comprising two fingers equipped with claws and comprising a means of fixing the lamps; 
       FIG. 4  is a plan view of the lamp holder in  FIG. 3 , the means of fixing the lamp being in the open position. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   For the remainder of the description, longitudinal, vertical and transverse orientations indicated by the trihedron L, V, T, in  FIG. 1  will be adopted. The longitudinal orientation is directed from rear to front in the direction indicated by the arrow “L” of the trihedron. Hereinafter, similar analogous or identical elements will be designated by the same reference numbers. 
     FIG. 1  depicts a motor vehicle headlight  10 . The headlight  10  comprises a reflector  12  and a lamp holder  14 . 
   The reflector  12  has here the shape of a dome open longitudinally towards the front. The reflector  12  comprises here a longitudinal optical axis “A”. The rear end top of the reflector  12  comprises a orifice  16  for a lamp  18  to pass. 
   The lamp holder  14  comprises a body with a roughly cylindrical tubular shape with a longitudinal principal axis “A” and is delimited radially by a roughly cylindrical wall  24 . 
   For the remainder of the description, the radial orientations will all be defined with respect to the principal axis “A” of the lamp holder  14 . Thus a radial plane will be orthogonal to the principal axis “A”. Tangential orientations that extend in a radial plane tangent to the cylindrical wall  24  of the lamp holder  14  are also defined. 
   A front end portion  20  of the lamp holder  14  is conformed so as to be able to be inserted longitudinally towards the front in the rear orifice  16  of the reflector  12 , then fixed during an operation of mounting the lamp holder  14 . 
   The wall  24  of the lamp holder  14  is then in electrical contact with the reflector  12 . 
   When the lamp holder  14  is mounted in the reflector  12 , a rear end portion  22  of the lamp holder  14  projects longitudinally towards the rear with respect to the reflector  12 . 
   The cylindrical wall  24  of the rear end portion  22  of the lamp holder  14  has an external cylindrical face. The rear end portion  22  is delimited longitudinally towards the rear by a circular rear end  26 . 
   The lamp  18  is here an arc lamp that is intended to be mounted in the lamp holder  14 . The lamp  18  has a front cylindrical bulb  27  that is fixed in a rear cap  30  axisymmetric with respect to the principal axis “A”. The rear cap  30  comprises a radial collar with a diameter greater than that of the bulb  27 . 
   The rear end of the rear cap  30  has means of electrical connection to a high-voltage connector  32  so as to be supplied with electricity. 
   The high-voltage connector  32  comprises connection means complementary to those of the cap  30  which are arranged at the front of the body of the high-voltage connector  32 . 
   In a known manner, for mounting the high-voltage connector  32  on the cap  30  of the lamp  18 , the cap  30  of the lamp  18  has first bayonet mounting means that cooperate with second bayonet mounting means carried by the high-voltage connector  32 . In the example depicted in  FIG. 1 , the cap  30  of the lamp  18  has radial lugs that cooperate with grooves in the shape of an “L” (not shown) carried by the connector  32 . 
   The lamp holder  14  has an internal radial shoulder face  28  that separates the front end portion  20  from the rear end portion  22 . The shoulder face  28  is sized so that the bulb  27  of the lamp  18  can pass longitudinally towards the front portion  20  through the lamp holder  14  but so that the collar of the cap  30  comes into abutment against the shoulder face  28 . 
   The lamp holder  14  also comprises means of fixing the cap  30  of the lamp  18  in a mounted position, which will be described in more detail below. 
   When the lamp  18  is mounted in the lamp holder  14 , the lamp  18  is inserted coaxially from rear to front inside the lamp holder  14 , the bulb  27  being directed towards the front, until the cap  30  is in abutment against the shoulder face  28 . The lamp  18  is then fixed to the lamp holder  14  by means of the spring  58 . The cap  30  of the lamp  18  is thus housed inside the rear end portion  22  of the lamp holder  14 , whilst the bulb  27  projects longitudinally towards the front with respect to the lamp holder  14  inside the reflector  12 . 
   The high-voltage connector  32  is then mounted on the cap  30  of the lamp  18  after the lamp  18  has been mounted in the lamp holder  14 . 
   During the operation of mounting the connector  32 , the cap  30  is inserted axially in the front connection means of the high-voltage connector  32 , and then the connector  32  is fixed to the cap  30  by pivoting about the principal axis “A”, for example by pivoting a quarter of a turn in the clockwise direction. 
   In order to electrically connect the lamp holder  14  to the high-voltage connector  32 , the lamp holder  14  is equipped with claws  34  that are arranged so as to be in contact with a portion  43  of the body of the high-voltage connector  32  referred to as the contact portion  43 . 
   The claws  34  are more particularly in contact with an external surface portion  33  of the connector  32  and produced from an electrically conductive material and electrically connected to the vehicle earth. 
   According to the teachings of the invention, the claws  34  are carried by longitudinal fingers  36  and extend in a tangential direction with respect to the cylindrical wall  24  of the rear of the end portion  22  of the lamp holder  14 . 
   The lamp holder  14  comprises here two fingers  36  that each carry three claws  34 . In the example depicted in the figures, the fingers  36  are arranged at two diametrically opposed points on the lamp holder  14 . According to the type of connector used, they can of course be disposed on the portion  22  in a different non-symmetrical configuration. This has the advantage of greater flexibility in the design of the lamp holder according to the invention. 
   Each finger  36  has a front end portion  38  that is fixed against the external cylindrical face of the wall  24  of the lamp holder  14 . Each finger  36  also comprises a rear end portion  40  that extends longitudinally towards the rear with respect to the rear end  26  of the lamp holder  14 , and which carries the claws  34 . 
   The finger  36  and claws  34  are produced from an electrically conductive material such as copper. 
   Advantageously, the claws  34  and the finger  36  that carries them are produced in one piece. 
   The claws  34  extend here from the finger  36  in a tangential direction that is orientated in the direction of pivoting for the bayonet mounting of the high-voltage connector  32 . The claws  34  carried by a finger  36  are arranged parallel to one another and longitudinally one behind the other so that the rear end portion  40  and the claws  34  form a comb, as depicted in  FIG. 2 . 
   Each claw  34  has a free end portion  42  curved so that the convex face of the claws  34  is directed towards the principal axis “A” of the lamp holder  14 . These curved portions  42  are intended to be in electrical contact with the contact portion  43  of the mounted high-voltage connector  32 . 
   The contact portion  43  of the external surface of the body of the connector that is opposite the claws  34  has a cylindrical shape so that the curved portion  42  of the claws  34  slides over the body of the connector  32  when it pivots. 
   The claws  34  are elastically deformable in flexion in a radial direction so that, when the connector pivots for its bayonet mounting or removal, the claws  34  are able to flex to facilitate pivoting. The curved portions  42  thus guide the claws  34  in flexion like a cam against a cam follower. 
   The elasticity of the claws  34  in particular makes it possible to reduce the friction of the claws  34  against the body of the connector  32 . 
   In addition and non-limitingly, the contact portion  43  of the body of the connector  32  can also comprise angular location means in relief, for example protrusions, in which the curved portions  42  of the claws  34  can fit in the mounted position of the connector  32 . 
   The front end portion  38  of the finger  36  is pressed against the external cylindrical face of the wall  24  of the lamp holder  14  so as to be in electrical contact with the wall  24  of the lamp holder  14 . 
   The finger  36  is fixed to the cylindrical wall  24  of the rear end portion  22  of the lamp holder  14  by elastic fitting of the front end portion  38  of the finger  36  in a housing with complementary shapes carried by the lamp holder  14 . 
   The housing is here formed by a first rear carrier  44  and a second front carrier  44  that are arranged longitudinally one behind the other on the external cylindrical face of the wall  24  of the lamp holder  14  so that the front end portion  38  of the finger  36  is mounted in a longitudinal sliding movement from rear to front between the external cylindrical face of the wall  24  of the lamp holder  14  and the carriers  44 . 
   The carriers  44  are here produced by cropping and pressing of the wall  24  of the lamp holder  14 . 
   The front end portion  38  of the finger  36  has a radial shoulder face  28  intended to be in contact with a facing rear end edge  48  of the rear carrier  44  in order to lock the forward sliding of the finger  36 . The shoulder face  46  is here carried by two opposite lugs  50  that extend perpendicular to the finger  36 . 
   The front end portion  38  of the finger  36  also has a lug  3252  that extends radially towards the outside so as to be received by elastic deformation in an associated aperture  54  carried by the lamp holder  14  in order to lock the rearward sliding of the finger  36 . The aperture  54  is here delimited longitudinally towards the front and towards the rear by the two carriers  44 . 
   The finger  36  is thus locked longitudinally in the mounted position by the shoulder face  46  and by the lug  52 . 
   According to a variant of the invention that is not shown, the lug  52  can be produced in the external cylindrical face of the wall  24  of the lamp holder  14 , and the lug  52  can then extend radially towards the inside of the lamp holder  14 . 
   According to a variant, not shown, of the means of fixing the finger  36 , the finger  36  is fixed to the wall  24  of the lamp holder  14  by means of a fixing clamp that is clamped or crimped around the external cylindrical face of the wall  24  of the rear end portion  22  of the lamp holder  14 . 
   The cylindrical contact portion  43  ( FIG. 1 ) of the body of the high-voltage connector  32  having a diameter greater than that of the rear end portion  22  of the lamp holder  14 , the finger  36  comprises here an inclined intermediate portion  56  ( FIG. 2 ) so that the rear end portion  40  of the finger  36  is offset radially towards the outside with respect to the front end portion  38  of the finger  36  so that the claws  34  of one finger  36  are sufficiently separated from the claws  34  of the other finger  36  to allow passage of the body of the high-voltage connector  32 . The outward offset of the rear end portion  40  with respect to the front end portion  38  of the finger  36  will of course depend on the type of high-voltage connector used. 
   To increase the rigidity of the finger  36 , the finger  36  comprises a longitudinal rib that extends from the rear front end portion  38  as far as the rear end of portion  40 , running along the immediate portion  56 . Thus only the claws are liable to deform during the operation of mounting the high-voltage connector  32  whilst the finger  36  are not deformed. 
   According to another aspect of the invention depicted in  FIGS. 3 and 4 , the lamp holder  14  also comprises means for fixing the lamp  18  to the lamp holder  14 . More particularly, the lamp holder  14  has a spring  58  that has a transverse pivoting axis  60  that is received in a hinge  62  in the lamp holder  14  so that the pivot axis  60  extends substantially tangentially with respect to the cylindrical wall  24  of the lamp holder  14 . 
   The spring  58  also comprises two arms  64  that extend symmetrically with respect to a mid-plane of the pivot axis  60  from the ends of the pivot axis  60  in a plane substantially radial with respect to the principal axis “A”, passing through the internal circular space delimited radially by the cylindrical wall  24  of the lamp holder  14 . Each arm thus has a first end  66  for connection with the pivot axis  60  and a second free end  68 . 
   The arms  64  are produced in one piece with the pivot axis  60 , preferably by folding a wire produced from a metal material having elastic properties. 
   Thus the end  66  of each arm  64  connecting with the pivot axis  60  is elastically deformable in flexion so that the arms  64  can be controlled between a closed position in which the free ends  68  are close to each other and an open position in which the free ends  68  are separated from each other and towards which the arms  64  are returned elastically. 
   For this purpose, the free ends  68  of the arms  64  are conformed so as to be able to be gripped between two fingers of an operator. 
   As depicted in broken lines in  FIGS. 3 and 4 , when the arms  64  of the spring  58  are in the closed position, the cap  30  of the lamp  18  is able to be locked in the stop position against the shoulder face  28  of the lamp holder  14  by the arms  64 , which bear on the rear face of the collar of the cap  30 . 
   As depicted in  FIGS. 3 and 4 , in their open position the arms are arranged laterally on each side of the cap  30  so as to allow the longitudinal sliding of the lamp  18  towards the rear with respect to the lamp holder  14 . 
   Moreover, the cylindrical wall  24  of the rear end portion  22  of the lamp holder  14  has an opening  70  arranged so as to be diametrically opposed to the hinge  62 . The opening  70  is for example obtained by cropping the wall  24 . The opening  70  is intended to allow the passage of the free ends  68  of the arms  64  through the wall  24  of the lamp holder  14  towards the outside. 
   The opening  70  is delimited laterally by two lateral longitudinal walls  71  and longitudinally by a front edge and a rear edge  75 . 
   Each lateral wall  71  comprises a first front notch  72  and a second rear notch  74  that are formed in the cylindrical wall  24  of the lamp holder  14  and that are intended to receive an associated arm. The front  72  or respectively rear  74  notch in a lateral wall  71  is arranged opposite the front  72  or respectively rear  74  notch in the opposite lateral wall  71 . 
   The front notch  72  is less deep than the rear notch  74 . The front notch  72  is intended to lock the arms  64  in their closed position whilst the second rear notch is intended to lock the arms in the open position. 
   For passage of the arms  64  from one notch to the other, the spring  58  pivots about its pivot axis  60  and thus the arms are mounted so as to be able to move between a closed front position for locking the lamp  18  in the mounted position and a closed rear position for removing the lamp  18 . 
   In the open rear position, the pivoting of the arms about the pivot axis  60  is locked in both directions by the front and rear lips of the rear notch  74 . 
   Likewise, in the closed front position, the pivoting of the arms about the pivot axis  60  is locked in both directions by the front and rear lips of the front notch  72 . 
   For mounting the arms  64  in the opening  70 , a longitudinal slot  76  is produced in the wall  24  between the rear end  26  of the lamp holder  14  and the rear edge  75  of the opening  70 . The slot  76  is more particularly arranged at the center of the rear edge  75  of the opening  70 . 
   The bottom mounting slot  76  has a width less than the width of the rear edge  75  of the opening  70 , so that, when the arms  64  pass from their closed front position to their open rear position, the pivoting of the arms  64  about the pivot axis  60  towards the rear is limited by the rear edge  75  arranged between the slot  76  and the notch  74 . 
   In addition, the slot has a width such that only one arm at a time can pass through the slot  76 . 
   Thus the rear lip of the rear notches  74  and the rear edge  75  of the opening  70  form stops that are able to limit the rearward pivoting of the arms  64  with respect to the pivot axis  60  in order to prevent the arms encumbering the space situated at the rear of the lamp holder  14  when the spring  58  is in its open position, and thus preventing the arms  64  constituting an interference in this open position. 
   In addition, the free ends  68  of the arms  64  being held in determined positions by the front  72  and rear  74  notches, an operator can perform the mounting and removal operation with a single hand without necessarily seeing the lamp holder  14 . 
   Advantageously, the rear end  26  of the lamp holder  14  is beveled on each side of the slot  76  so as to guide the arms  64  towards the slot  76  when the spring  58  is being mounted on the lamp holder  14 . 
   When the lamp  18  is mounted in the lamp holder  14 , the spring  58  ( FIG. 1 ) is in the separated rear position ( FIG. 4 ). The lamp  18  is then inserted longitudinally from rear to front inside the lamp holder  14  ( FIG. 4 ), with the bulb  27  towards the front. 
   Then, when the cap  30  is in abutment against the shoulder face  28 , the spring  58  is controlled towards its front closed position so that the lamp  18  is fixed in +the lamp holder  14 . The free ends  68  and the arms  64  are gripped by an operator so that each of the arms  64  emerges from the associated rear notch  74 . 
   The arms  64  are then free to pivot about the pivot axis  60  towards the front. Their pivoting towards the rear is in fact limited by the rear edge  75  of the opening  70 . When the arms  64  are facing the front notches  72 , the operator releases his gripping force and the arms separate elastically towards their closed position, entering the associated front notch  72 . 
   Next the high-voltage connector  32  is mounted on the lamp  18 . Initially the connector  32  is positioned against the cap  30  of the lamp  18  by longitudinal sliding of the connector  32  from rear to front with respect to the cap  30 . The contact portion  43  of the body of the connector  32  is thus in contact with the claws  34 . 
   Secondly, the connector  32  is pivoted about the principal axis “A” with respect to the cap  30 . The contact portion  43  of the body of the connector  32  slides against the curved portion  42  of the claws  34 , if necessary lifting them radially automatically when the external surface of the body of the connector  32  has reliefs or imperfections. 
   While the form of apparatus herein described constitutes a preferred embodiment of this invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.