Abstract:
A vehicular lamp has a lamp unit with a light source and controls light from the light source to obtain a predetermined light distribution, and an actuator that rotates the lamp unit using an output shaft to change a direction of illumination. A direction for drawing out an external cord that is connected to a connector, which is provided in the actuator for admitting electric power and/or a signal from outside, is set toward the vehicle front or vehicle side in the actuator.

Description:
RELATED APPLICATIONS 
   This claims the benefit of the priority of Japanese Application No. P.2004-31040, filed Feb. 6, 2004, which is hereby incorporated herein in its entirety. 
   TECHNICAL FIELD 
   The present disclosure relates to a new vehicular lamp. More specifically, the present disclosure relates to a way for reducing a depth dimension of a vehicular lamp. 
   BACKGROUND 
   Techniques are known for changing a lateral illumination direction of a vehicular lamp in accordance with a steering operation. 
   Such a vehicular lamp is shown, for example, in Japanese Patent Laid-Open Publication No. 2002-160581. There, a lamp unit with a configuration rotatable in a lateral direction is provided with a lamp body ( 3 ) and a light source bulb ( 23 ) supported by the lamp body ( 3 ). In addition, a rotation shaft (output shaft) ( 16 ) of a driving portion (actuator) is connected to the lamp body. The rotation shaft ( 16 ) is rotated by electric power and a signal supplied via an external cord connected to a connector, whereby the lamp body ( 3 ) is rotated in the lateral direction so as to change an illumination direction of light distribution thereof in the lateral direction. 
   However, in the vehicular lamp described there, the connector of the actuator ( 11 ) is disposed facing toward the rear; therefore, the external cord for supplying electric power and a signal from the outside to the actuator ( 11 ) is drawn out toward the rear. 
   Moreover, a cord ( 27 ) for supplying electric power to the light source bulb ( 23 ) is disposed so as to extend toward the rear of the lamp body ( 3 ). If the external cord for supplying electric power and the signal to the actuator ( 11 ) is also positioned toward the rear, a wide rear space inside the lamp thus becomes required, which increases the dimensions of a depth direction of the lamp. Moreover, high-voltage electric power is required when a discharge bulb is used in the light source bulb. This necessitates a thicker power cord for the light source bulb in order to supply high-voltage electric power and prevent electromagnetic radiation. Consequently, such a power cord has little flexibility, and moves considerably in the lateral direction in conjunction with rotation of the lamp body ( 3 ) in the lateral direction. A significantly large space is thus required in order to ensure that the external cord for supplying electric power and the signal to the actuator ( 11 ) is positioned in a rear portion of the lamp so as not to interfere with the movement of the power cord. This inevitably requires the lamp to have a large rear protrusion. 
   Due to increased function and performance, there is an extremely high density of parts and devices disposed in the space underneath the hoods of recent automobiles, and designers are forced to find increasingly innovative methods for efficiently placing each device and part. In light of such conditions, it is extremely difficult nowadays to secure a large space for the placement of a lamp in a front portion of an automobile, especially space in the depth direction. 
   The present disclosure was made in light of the foregoing circumstances. 
   SUMMARY 
   The present disclosure relates to drawing out an external cord that is connected to a connector, which is provided in the actuator for admitting electric power and/or a signal from outside, toward the front or the side of the vehicle in the actuator. 
   According to an embodiment of the present invention, there is no need to secure a space at the rear of internal space in the vehicular lamp to position the external cord, making it possible to reduce a dimension of the vehicular lamp in the depth direction. 
   A vehicular lamp has a lamp unit with a light source and controls light from the light source to obtain a predetermined light distribution. An actuator rotates the lamp unit using an output shaft to change a direction of illumination. A direction for drawing out an external cord that is connected to a connector, which is provided in the actuator for admitting electric power and/or a signal from outside, is set toward either the vehicle front or the vehicle side in the actuator. 
   According to an embodiment of the present invention, there is no need to secure a space at the rear of internal space in the vehicular lamp to position the external cord for supplying electric power and/or a signal to the actuator. Therefore, it is possible to reduce a dimension of the vehicular lamp in the depth direction. 
   In the invention according to another embodiment, the connector is provided on a front side of the actuator, and an outer shape of the actuator is symmetrical along a line that connects the output shaft and the connector. The actuator can therefore be used for both vehicular lamps mounted on the right and left sides of the vehicle, thus suppressing manufacturing costs. 
   In the invention according to still another embodiment, the lamp unit and the actuator are disposed inside a lamp chamber defined by a lamp body and a translucent cover that covers a front surface side of the lamp body, and an extension that covers a front of the connector and the external cord connected to the connector is disposed inside the lamp chamber. Therefore, the overall appearance of the vehicular lamp in a front view is not spoiled by exposure of the connector and the external cord. 
   In the invention according to a further embodiment, the light source is a discharge bulb to which electric power is supplied by a power cord extending from a bottom portion of the lamp chamber. There is thus no interference between the power cord to the discharge bulb and the external cord to the actuator, which assures that there is no leakage of high voltage due to interference. 
   Various other features and advantages may be readily apparent from the following detailed description, the accompanying drawings, and the claims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows a vehicular lamp according to an embodiment of the present invention, and is a longitudinal cross-sectional view thereof. 
       FIG. 2  is an exploded perspective view of a main portion of the embodiment of  FIG. 1 . 
       FIG. 3  is a plane view of an internal structure of an actuator. 
       FIG. 4  is a cross-sectional view taken along a line IV-IV in  FIG. 3 . 
       FIG. 5  is a plane view of an internal structure of an actuator showing a modification. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   As is apparent in  FIGS. 1 and 2 , a vehicular headlamp  1  is provided with a lamp body  10  including a concave portion with an opening that faces forward, and the front opening of the lamp body  10  is covered by a translucent cover  20  to form a lamp chamber  30 . A bracket  40  is disposed inside the lamp chamber  30 , which is supported tiltable with respect to the lamp body  10 , and a lamp unit  50  tiltable in the horizontal direction is supported by the bracket  40 . 
   The lamp unit  50  has a reflector  51 , light source bulb  52  supported by the reflector  51 , a light projection lens  53  provided so as to cover a front of the reflector  51 , and a shade  54  to limit an upper edge of a pattern of radiated light (light distribution pattern). The reflector  51  has a reflective surface  51   a  with a light condensing property. The light projection lens  53  has a convex lens shape and is supported on an end portion of an assembly frame  55 , which has a generally cylindrical shape and is fixed to a front end portion of the reflector  51 . 
   Light radiating from the light source bulb  52  and reflected by the reflective surface  51   a  of the reflector  51  is condensed in the vicinity of an upper edge  54   a  of the shade  54 . In addition, a focal point of the light projection lens  53  is positioned in the vicinity of the upper edge  54   a  of the shade  54 . Accordingly, a beam with an upper edge of a light distribution pattern thereof limited by the upper edge  54   a  of the shade  54  is radiated forward by the light projection lens  53 . 
   A fulcrum shaft  56  protrudes upward from a top surface of a rear end portion of the assembly frame  55 . Likewise, a connecting boss  57  protrudes downward from a bottom surface of the rear end portion. A connecting concave portion  57   a  is formed opening downward on the connecting boss  57 . It should be noted that the center of the connecting concave portion  57   a  and the center of the fulcrum shaft  56  are positioned on the same axis. 
   In the lamp unit  50 , the fulcrum shaft  56  is rotatably supported on a shaft-supporting portion  42  provided on a front end portion of a mounting part  41 , which is on a top side of the bracket  40 . The connecting boss  57  is inserted to penetrate toward a bottom side of an insertion hole  44  provided in a front end portion of a mounting part  43 , which is on a bottom side of the bracket  40 . Furthermore, a rear end portion of the lamp unit  50  protrudes toward the rear from a large opening  45  provided in the bracket  40 . 
   As is clearly apparent in  FIG. 2 , an upper portion of the bracket  40  is supported by pivot fulcrum portions  60 ,  60  at two points spaced apart in the horizontal direction; and a lower portion is supported via a leveling actuator  70 . 
   The pivot fulcrum portion  60  is constructed from a nut body  62  that is supported by the bracket  40  and an adjustment shaft  61  rotatably supported on a rear surface wall  11  of the lamp body  10 . The adjustment shaft  61  has a head portion  61   b  fixedly formed with a rear end of a screw shaft portion  61   a,  wherein the head portion  61   b  protrudes toward a rear side of the rear surface wall  11  of the lamp body  10 , and the adjustment shaft  61  can be rotated by operating the head portion  61   b.  The nut body  62  is supported in a state capable of moving somewhat so as to tilt with respect to the bracket  40 , and the screw shaft portion  61   a  of the adjustment shaft  61  is screwed into the nut body  62 . Accordingly, operating the adjustment shaft  61  by rotation will screw or unscrew the screw shaft portion  61   a  into or out of the nut body  62  depending on the direction of rotation. Therefore, the space can be varied between the rear surface wall  11  of the lamp body  10  and the portion supporting the nut body  62  of the bracket  40 . Note that the pivot fulcrum portion  60  shown is configured so as to have an adjustable space between the bracket  40  and the rear surface wall  11  of the lamp body  10 ; however, it may also be configured such that the space between the bracket  40  and the lamp body  10  is not adjustable. 
   The leveling actuator  70  has a configuration in which a sliding shaft  72  protrudes from a front end of a housing  71  with a driving mechanism provided therein. A sphere  72   a  is formed on a front end of the sliding shaft  72 . Driving of the driving mechanism within the housing  71  moves the sliding shaft  72  in the longitudinal direction with respect to the housing  71 . In addition, the driving mechanism within the housing  71  is designed to drive as appropriate according to an automatic control based upon remote operation from the driver&#39;s cab, or output from a sensor that detects tilting in a vehicular longitudinal direction or the like. A globe acceptor  73  is supported at a position below a position supporting one of the nut bodies  62 ,  62  among the bottom end portions of the bracket  40 . The sphere  72   a  on the front end of the sliding shaft  72  engages in a rotatable state with a spherical concave portion (not shown) of the sphere acceptor  73 . Furthermore, the leveling actuator  70  is fixedly supported by the lamp body  10 . Accordingly, driving of the leveling actuator  70  moves a portion supporting the sphere acceptor  73  in the bottom end portion of the bracket  40  in the longitudinal direction with respect to the lamp body  10 . Consequently, the bracket  40  is rotated in the up-down direction around a rotation axis consisting of a line connecting the nut bodies  62 ,  62  of the pivot fulcrum portions  60 ,  60 . 
   The mounting parts  41 ,  43  of the bracket  40  mentioned above protrude forward from both the top and bottom edges of the large opening  45  with a generally oblong shape. In addition, attachment bosses  43   a,    43   a  protrude from a bottom surface of the mounting part  43  on the bottom side. 
   The lamp unit  50  is rotated in the lateral direction by a swivel actuator  80  that is supported by the mounting part  43  on the bottom side of the bracket  40 . 
   As apparent in  FIGS. 2 to 4 , the swivel actuator  80  has a configuration where an output shaft  82  protrudes upward from a position on a front end of a housing  81 , an outer shape of which is somewhat long in the longitudinal direction and flat in the vertical direction. 
   The housing  81  has two attachment parts  81   a,    81   a  that protrude toward the sides. Furthermore, attachment screws  81   c,    81   c  inserted from below into insertion holes  81   b ,  81   b  of the attachment parts  81   a,    81   a  are screwed into the attachment bosses  43   a,    43   a  provided protruding from the bottom surface of the mounting part  43  on the bottom side of the bracket  40 . Thus, the swivel actuator  80  is fixed to the bottom surface of the mounting part  43  on the bottom side of the bracket  40 . 
   On an outer peripheral surface of an upper end portion of the output shaft  82 , a plurality of engagement projections  82   a,    82   a , . . . are provided so as to protrude extending in an axial direction. By internally engaging the upper end portion of the output shaft  82  with a connecting concave portion  57   a  of the lamp unit  50 , the engagement projections  82   a,    82   a , . . . of the output shaft  82  become engaged with engagement grooves (not shown) formed on an inner peripheral surface of the connecting concave portion  57   a.  Slipping between the output shaft  82  and the connecting concave portion  57   a  in the rotational direction is thus prevented, and the rotation of the output shaft  82  is securely transmitted to the lamp unit  50 . 
   A connector  84  for connecting an external cord  83 , which supplies electric power and a signal to a driving mechanism inside the housing  81 , is positioned in a state facing forward at a center of the front end portion of the housing  81  in the lateral direction. Accordingly, as apparent in  FIG. 1 , the external cord  83  connected to the connector  84  is positioned so as to be drawn out forward from a front end portion of the swivel actuator  80 . Furthermore, the external cord  83  is drawn outside of the lamp from an insertion hole  13   a  formed in a bottom surface wall  13  of the lamp body  10 . It should be noted that a reference numeral  14  denotes a rubber bushing mounted to the insertion hole  13   a.  In addition, the insertion hole  13   a  may also be provided at a position offset in the vehicular width direction. 
   As is apparent in  FIG. 1 , an extension  12  is disposed on the front end portion inside the lamp chamber  30 . The extension  12  is disposed so as to be positioned at a portion between the front end portion of the lamp unit  50  and the front opening edge of the lamp body  10 , and is provided with an opening  12   a  that faces forward a portion excluding a peripheral edge of the light projection lens  53  of the lamp unit  50 . A front surface  12   b  is a visible surface with an excellent appearance. Therefore, although the connector  84  is positioned on the front end of the swivel actuator  80 , and the external cord  83  connected to the connector  84  is drawn out forward, the external cord  83  and the front end portion of the swivel actuator  80  are completely blocked in front by the extension  12 . Accordingly, the appearance of the vehicular headlamp  1  is not spoiled, because the external cord  83  and the swivel actuator  80  are not seen through the translucent cover  20 . 
   As is clearly apparent in  FIGS. 3 and 4 , a brushless motor  85  is disposed as a driving source inside the housing  81 , and the rotation of the brushless motor  85  is transferred to the output shaft  82  via a transfer gear system. Namely, a sector gear  82   b  is fixedly formed on the output shaft  82 , and the rotation of the motor  85  is transferred to the sector gear  82   b  via three transfer gears  86 ,  87 ,  88 , thereby rotating the output shaft  82  fixed with the sector gear  82   b.  The respective transfer gears  86 ,  87 ,  88  have large gears  86   a,    87   a,    88   a  and small gears  86   b,    87   b,    88   b  fixedly formed on like axes. The large gear  86   a  of the transfer gear  86  engages with a pinion gear  85   b  fixedly formed with a rotor  85   a  of the motor  85 ; the small gear  86   b  of the transfer gear  86   a  engages with the large gear  87   a  of the transfer gear  87 ; the small gear  87   b  of the transfer gear  87  engages with the large gear  88   a  of the transfer gear  88 ; and the small gear  88   b  of the transfer gear  88  engages with the sector gear  82   b.    
   As is apparent in  FIGS. 2 and 3 , the outer shape of the swivel actuator  80  is symmetrical along an extending line CL that connects the output shaft  82  and the connector  84 . Normally, headlamps for automobiles have different shapes for those disposed on the right side and those disposed on the left side of the automobile. In other words, a right-side headlamp has a shape symmetrical to the left-side headlamp. Accordingly, parts and members used for the left-side headlamp and parts and members used for the right-side headlamp are normally exclusive to each other. However, the swivel actuator  80  has an outer shape that is symmetrical, thus allowing it to be used for both the left-side headlamp and the right-side headlamp. Therefore, manufacturing costs can be kept lower than in the case of preparing separate actuators for the right and left sides. 
   A discharge bulb is used in the light source bulb  52  of the lamp unit  50 . Therefore, a lighting circuit unit  90  with a lighting circuit for lighting a discharge bulb  52  is disposed in a bottom portion inside the lamp body  10 . An end of a power cord  91  extending from the lighting circuit unit  90  is connected to a bulb socket  92 , and the bulb socket  92  is connected to the light source bulb  52 . Accordingly, lighting voltage generated by the lighting circuit provided inside the lighting circuit unit  90  is applied to the light source bulb  52  via the bulb socket  92 , thereby lighting the light source bulb  52 . Since high-voltage electric power is required to light the discharge bulb, this necessitates a thicker power cord  91  for the light source bulb  52  in order to supply high-voltage electric power and prevent electromagnetic radiation, as well as requiring a metallic (mesh) coating for preventing electromagnetic radiation. Consequently, such a power cord  91  has little flexibility, and moves considerably in the lateral direction of the rear portion of the lamp chamber  30  in conjunction with rotation of the lamp unit  50  in the lateral direction. In addition, the external cord  83  for supplying electric power and a signal to the swivel actuator  80  is not positioned in the rear portion of the lamp chamber  30 , which has space for movement of such a power cord  91 . Therefore, only space for the movement of the power cord  91  need be secured in the rear portion of the lamp chamber  30 , thus allowing for a smaller amount of protrusion of the lamp body  10  toward the rear. In other words, it is possible to reduce a dimension of the vehicular headlamp  1  in the depth direction. 
   Furthermore, the external cord  83  and the power cord  91  do not interfere with each other upon rotation of the lamp unit  50 , thus assuring that there is no leakage of high voltage due to contact between the external cord  83  and the power cord  91 . It should be noted that disposing a connector  84 A facing toward the side is also effective for avoiding interference between the external cord  83  and the power cord  91  as shown in  FIG. 5 . 
   Note that the shapes and structures of each portion shown in the above embodiment are but one specific example for carrying out the present invention, and must not be construed as limiting a technical scope of the present invention. 
   The present invention is suitable for application to a vehicular lamp that has an internal actuator and which requires a compact size, especially in the depth direction. 
   Other implementations are within the scope of the following claims.