Abstract:
A reduced depth headlamp assembly for use in a motor vehicle. The housing includes an exterior lens, and a mirror, and defines a housing axis extending between the exterior lens and the mirror. The projector includes a light source, a reflector, and a condenser lens co-axially arranged along a projector axis defined between the light source and the condenser lens. The projector is mounted to the housing such that the projector axis and the housing axis form an angle, preferably a ninety (90) degree angle, thereby minimizing the depth of the assembly.

Description:
BACKGROUND 
     1. Field of the Invention 
     The present invention generally relates to automotive headlamp assemblies. More specifically, the invention relates to a halogen or HID projector headlamp assembly having a reduced packaging depth. 
     2. Description of Related Art 
     Typically, two automotive headlamp assemblies are positioned on the front of a motor vehicle. These assemblies often house multiple features including low beam, high beam, park lamp, turn indicator, front side reflectors and front side markers. All of these functions must be contained within a package volume that often has available significantly greater width and height than depth. The limited depth results from design constraints that often position other components, such as the battery, engine, radiator and wheels, as far toward the front end of the vehicle as possible. Therefore, while there may be significant unused space horizontally (cross-car) and vertically, these other components limit the amount of depth available. 
     This is particularly problematic with existing projector headlamp assemblies using halogen or HID lamp projectors for the low and high beam functions. Compared to reflector headlamp assemblies, projector headlamps reduce the width and height necessary for the low and high beam functions, but are heavier and significantly longer. However, as noted above, motor vehicles often have limited depth available for headlamps, making the increased length of projector headlamps a significant disadvantage. 
     In addition projectors are also problematic for vehicles using concealed headlamps. A concealed headlamp usually hides the headlamp assembly beneath a headlamp door. When the headlamps are not in use, the headlamp door is closed, concealing the headlamps from view. Upon activation of the headlamps, the headlamp door opens and rotates the headlamp assembly into its operating position. 
     While this is a practical arrangement for older, reflector style headlamps, it is less practical for projector style headlamps. The additional length of projectors requires longer headlamp doors, limiting styling options. In addition, the additional weight of the projectors requires more robust headlamp doors and/or actuators to rotate the projectors between the open and closed positions. 
     In view of the above, it is apparent that there exists a need for an improved projector headlamp assembly providing reduced depth and a better configuration for concealed headlamps. 
     SUMMARY 
     In satisfying the above need, as well as overcoming the enumerated drawbacks and other limitations of the related art, the present invention provides a reduced depth automotive headlamp assembly for use in a motor vehicle to illuminate, for example, a road. The headlamp assembly primarily comprises a housing and a projector lamp, with the housing including an exterior lens, a mirror, and a housing axis defined between the exterior lens and the angled mirror, and the projector lamp including a light source, a reflector, and a condenser lens co-axially aligned along a projector axis defined between the light source and the condenser lens. The depth of the headlamp assembly is reduced by mounting the projector lamp to the housing such that the projector axis and the housing axis form a projector angle. Any angle may be used, but a 90 degree angle will minimize the depth of the assembly. Relative to the vehicle, the projector may be oriented horizontally, vertically or anywhere in between, depending on the needs of a particular application. In operation, light emitted from the light source is focused by the condenser lens onto the mirror which is oriented at one-half the projector angle, and is redirected through the exterior lens and onto the road. 
     In another embodiment, the projector lamp may be pivotably coupled to the housing such that the housing is concealed from view when the headlamp assembly is “off,” and the housing rotates into view when the headlamp assembly is “on.” In this embodiment, the housing and mirror only come into proper alignment with the projector lamp after rotating into the “on” position. 
     In a third embodiment, the entire headlamp assembly described above may be pivotably mounted within the vehicle. In this embodiment, the housing is concealed from view when the headlamp assembly is “off,” and the entire assembly pivots together, bringing the housing into view when the headlamp assembly is “on.” 
     Further objects, features and advantages of this invention will become readily apparent to persons skilled in the art after a review of the following description, with reference to the drawings and claims that are appended to and form a part of this specification. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a top view of a reduced depth projector headlamp assembly embodying the principles of the present invention; 
         FIG. 2  is a left-front perspective view of a motor vehicle showing several components of the headlamp assembly of  FIG. 1 ; 
         FIG. 3  is a top view of a headlamp assembly according to  FIG. 1  having an alternate mirror configuration; 
         FIG. 4  is a side view of a headlamp assembly including a vertically oriented projector; 
         FIG. 5  is a side view of a headlamp assembly used in a pop-up headlamp configuration showing the housing in a closed position; 
         FIG. 6  is a side view of the headlamp assembly of  FIG. 5  showing the headlamp in an open position; and 
         FIG. 7  is a side view of an alternate configuration of the headlamp assembly of  FIG. 5  wherein the projector and housing pivot together. 
     
    
    
     DETAILED DESCRIPTION 
     Referring now to  FIG. 1 , a headlamp assembly embodying the principles of the present invention is illustrated therein and designated at  10 . As its primary components, the headlamp assembly  10  includes a housing  12 , a projector  14 , and a mirror  18 . The projector  14  is coupled to the housing  12  and the mirror is arranged to reflect light emitted from the projector  14  through a cover lens  20 .  FIG. 2  shows the headlamp assembly  10 , with the housing  12  omitted for clarity, arranged within a motor vehicle  11 . An arrow  15  illustrates the path of the light emitted from the projector  14 . 
     Returning to  FIG. 1 , the projector  14 , as mentioned above, is the light source for the headlamp assembly  10 . It is composed of a bulb assembly  22  mounted to a reflector  24  that directs light emitted from the bulb assembly  22  through a condenser lens  26  supported by a lens retainer  28  coupled to the reflector  24 . The bulb assembly  22 , reflector  24 , lens  26  and retainer  28  are co-axially aligned along a projector axis  30  and light emitted by the bulb assembly  22 , is focused by the condenser lens  26  along the projector axis  30 . The bulb assembly  22  includes any conventional light source, for example a halogen bulb, a high intensity discharge (HID) bulb or other light source. Some embodiments also include a solenoid  32  and a shield  34 , the solenoid  32  moving the shield  34  to alter the intensity of the light emitted by the projector  14  (i.e. to switch between low and high beam operational modes). 
     The housing  12  includes a frame  16  supporting the cover lens  20 , and the mirror  18 . The mirror  18  is arranged within the frame  16  such that any light directed through an opening  36  and upon the mirror  18  will be reflected through the cover lens  20  along a housing axis  38 . Additional exemplary features of the housing  12  may include turn light signals  40 , and lenses  41 , as well as reflectors  42 . 
     The mirror  18  may be any kind of appropriate reflective material, such as for example, polished metal, mylar, or silvered glass. While the mirror  18  shown in the embodiments of  FIGS. 1-7  is a single component, it is also possible to have multiple mirror segments (not shown) forming the mirror  18 . Furthermore, the mirror  18  may be formed as either an integral part of the housing  12 , such as a polished surface of the frame  16  itself or adhered to a surface of the frame  16  (as shown in  FIG. 1 ), or as a separate mirror  19  (as shown in  FIG. 3 ) supported with respect to the housing  12 . In addition, mirror adjustment screws  44 , configured to adjust the orientation of the mirror  18  from outside of the housing  12 , may also be provided. When used with a separate mirror  19 , the mirror adjustment screws  44  may increase the amount of adjustment available, but this is a more costly and mechanically complex arrangement than the integral mirror  18  shown in  FIG. 1 . In each of these embodiments, the mirror  18  or  19  is oriented at a mirror angle  46  with respect to the housing axis  38 . 
     The projector  14  as shown in  FIG. 1  is installed within the opening  36  such that the projector axis  30  is oriented at a projector angle  48  with respect to the housing axis  38 . The projector  14  may be coupled to the bezel  36  using any conventional fastening means. For example, the projector  14  may be adhered within the opening  36 , threaded into the opening  36 , attached by screws to the opening  36  or otherwise secured using any appropriate fastener or fastening means. Projector adjustment screws  52 , configured to adjust the orientation of the projector  14 , may also be included to help ensure this relationship. 
     To properly direct the light from the projector  14  through the cover lens  20  requires the mirror angle  46  to be one-half of the projector angle  48 . For example, the embodiment of  FIG. 1  shows a ninety (90) degree projector angle  48  and a forty-five (45) degree mirror angle  46 . This results in a minimum overall depth  50  of the headlamp assembly  10 . Other embodiments may use different projector angles  48  to meet the design and styling requirements of a particular application, so long as the above relationship with the mirror angle  46  is maintained. 
     Other orientations of the projector  14  that reduce the overall depth  50  of the headlamp assembly  10  are also possible. For example, while  FIGS. 1 and 3  show the projector  14  aligned horizontally within the motor vehicle  11  (see  FIG. 2 ), the projector  14  may instead be aligned as seen in  FIG. 4 , where the lens  20  is oriented toward the front of the motor vehicle (not shown) and the bulb assembly  66  is oriented down. In this embodiment, the projector  14  is rotated about the housing axis  35 , in this example, by ninety (90) degrees with respect to the housing  12 , into a vertical orientation (i.e., up and down) with respect to the motor vehicle  11  (not shown). By way of contrast, the projector  14  of the embodiment shown in  FIG. 2  runs horizontally (cross-car) with respect to the motor vehicle  11 . It is important to note other rotations of the projector axis  30  about the housing axis  38  are possible so long as the above relationship between the mirror angle  46  and the projector angle  48  is maintained. 
     In another embodiment, the headlamp assembly is concealed. In such a configuration, the headlamp assembly  10  is hidden from view beneath a headlamp door  56  when the headlamp assembly  10  is not in use (see  FIG. 5 ). When the headlamp is activated, the headlamp door  54  opens and a pivotable housing  58  rotates into an operating position (see  FIG. 6 ). The headlamp configuration shown in  FIGS. 7 and 8  is an example of a pop-up headlamp  54 . 
     Looking more closely at  FIG. 5 , in which like numerals denote similar components with the headlamp assembly  10 , the pop-up headlamp  54  is shown coupled to the headlamp door  56  in the “off” or closed position. When “off,” the headlamp  54  is concealed within the body of the motor vehicle  11 . A pivotable housing  58  is pivotably mounted at a pivot  62  to the vehicle  11  or to the projector  14  itself. The projector  14  is oriented vertically and mounted to the motor vehicle  11 . When the housing  58  is in the “off” position, the projector axis  30  and the housing axis  38  do not align as required above. 
     In the “on” or open position of  FIG. 6 , when the headlamp  54  is turned on, the headlamp door  54  and housing  58  rotates by means of an actuator  60  and “pops-up” into the operating position. Only when the housing  58  is in the “on” position does the projector axis  30  and the housing axis  38  align such that the mirror angle  46  is one-half of the projector angle  48 . 
     An alternate embodiment of the pop-up headlamp  54  is shown in  FIG. 7 . In this embodiment, the projector  14  is coupled to the pivotable housing  58 , rather than the motor vehicle  11 , in a similar fashion to the configuration of  FIG. 4 . As a result, only the pivotable housing  58  is pivotably mounted to the motor vehicle  11  at the pivot point  62 . Thus, when the headlamp  54  is turned on, the entire headlamp  54  including the headlamp door  56 , pivotable housing  58  and projector  14  are rotated by the pivot actuator  60  into the operating or “on” position shown in  FIG. 6 . In this embodiment, the projector angle  48  and the mirror angle  46  continuously remain in alignment throughout the range of motion of the pop-up headlamp  54 . 
     With regard to the pivot actuator  60 , it may be any mechanism capable of rotating the pop-up headlamp  54  into the operating or “on” position. This may include, for example, an electric motor, a stepper motor, a linear actuator, or vacuum system, and a hydraulic or pneumatic piston. The pivot actuator  50  is mounted to the vehicle  11  using any appropriate fastening method, for example, screws or rivets. 
     The present invention has great flexibility in meeting the design and stylistic requirements of a particular application over existing projector-style headlamp assemblies by reducing the overall depth  50  of the headlamp assembly  10 . For example, greater styling freedom is possible since the projector bulb is completely hidden from view. This also means luminance is decreased since oncoming vehicles will be exposed to the spot on the mirror surface, rather than directly to light from the condenser lens  26  as in the prior art. This reduces the “glare” seen by on-coming drivers. Other advantages include facilitating the replacement of projector bulbs by orienting the projector  14  toward more accessible locations within the vehicle, and facilitating the use of projectors in a “pop-up” configuration. 
     As a person skilled in the art will readily appreciate, the above description is meant as an illustration of implementing of the principles of the present this invention. This description is not intended to limit the scope or application of this invention in that the invention is susceptible to modification, variation and change, without departing from spirit of this invention, as defined in the following claims.