Abstract:
A gauge of a vehicle instrument cluster includes a dial having indicia thereon. A pointer is rotatably mounted in the instrument cluster and movable to a plurality of positions relative to the dial. A light source is disposed in the gauge and adapted to direct light in a first direction. A light diverting member is disposed adjacent to the light source and receives light from the light source. The light diverting member includes a first and a second light exit areas. The first light exit area is adapted to direct a first portion of the light generally away from the dial. The second light exit area is adapted to direct a second portion of the light generally toward the dial.

Description:
FIELD OF THE INVENTION 
   The present invention relates generally to vehicle instrument clusters and, more particularly, to an instrument cluster gauge incorporating a lighting configuration. 
   BACKGROUND OF THE INVENTION 
   Instrument clusters on automobiles generally include a plurality of gauges for displaying operational information such as vehicle speed, engine RPM, engine temperature, fuel level and many other information. The gauges may include analog or digital readings for displaying the information depending on the manufacturer and styling preferences. An analog gauge typically includes a faceplate having indicia thereon such as numbers and a pointer for rotating to the appropriate number, level, etc. 
   One important design consideration for an instrument cluster and related gauges is the ability of a vehicle operator to easily view and read the gauges in all driving environments. One aspect to consider when designing an instrument cluster gauge is to provide numbers and other indicia that may be easily viewed by the operator. Typically an instrument cluster gauge is illuminated by a light source such as a light bulb or light emitting diode (LED) as examples. 
   SUMMARY OF THE INVENTION 
   A gauge of a vehicle instrument cluster includes a dial having indicia thereon. A pointer is rotatably mounted in the dial and movable to a plurality of positions relative to the dial. A light source is disposed proximate to the gauge and adapted to direct light in a first direction. A light diverting member is disposed adjacent to the light source and receives light from the light source. The light diverting member includes a first and a second light exit area. The first light exit area is adapted to direct a first portion of the light generally away from the dial. The second light exit area is adapted to direct a second portion of the light generally toward the dial. 
   According to other features, the light source further comprises a plurality of light sources adapted to direct light in a first direction. The first light exit area is adapted to reflect light in the form of a radial ring of light directed generally away from the dial. The radial ring of light is radially offset outboard of a path defined by a rotational sweep of the pointer. The light diverting member may be unitary and define a circular footprint. The plurality of light sources are arranged in a circular pattern. 
   The light diverting member may define laterally offset inboard and outboard longitudinal portions connected by an intermediate angled portion. The light diverting member defines an outer angled portion extending from the outboard longitudinal portion. The outer angled portion directs light toward the dial. The intermediate angled portion directs light away from the dial. A mask is arranged adjacent to the light diverting member and is adapted to obscure view of the light diverting member from a vehicle operator. 
   Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
       FIG. 1  is a perspective view of an exemplary vehicle cabin having an instrument cluster including a vehicle speedometer according to the present teachings; 
       FIG. 2  is a front view of the vehicle speedometer of  FIG. 1  according to the present teachings; 
       FIG. 3  is a cross-sectional view of  FIG. 1  taken along line  3 — 3 ; and 
       FIG. 4  is an exploded perspective view of the speedometer of  FIG. 2 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. 
     FIG. 1  depicts an exemplary instrument cluster  10  in an automotive vehicle. The instrument cluster  10  may include various gauges and dials which are to be viewed and/or operated by an occupant of the vehicle. For example, a speedometer  12  may be used to display the speed at which a vehicle is traveling. The speedometer  12  according to the present teachings includes a movable pointer  14  ( FIG. 2 ) which correlates to the speed of the vehicle. To provide meaningful graphical information to the occupant, a dial or faceplate  20  of the speedometer  12  forms the background for the pointer  14  of the speedometer  12 . While the following discussion is specifically directed toward a speedometer, it is appreciated that the same may be applied to other gauges such as, but not limited to, a tachometer for example. 
   With reference now to  FIGS. 2–4 , the speedometer  12  according to the present teachings provides a lighting configuration in which a common light source provides illumination onto the dial  20  in the form of floodlighting F ( FIG. 3 ) as well as illumination around a periphery of the dial  20  in the form of a light ring R ( FIGS. 2 and 3 ). The floodlighting illuminates the entire dial  20  as well as the pointer  14  whereby supplemental lighting, such as through the pointer  14 , is unnecessary. An advantage of eliminating lighting through the pointer is that a lighting infrastructure consisting of wiring, printed circuit boards, light bulbs or LEDs, and a more complicated pointer, are not needed. As shown in  FIG. 2 , the light ring R is radially offset outboard of a tip of the pointer. As a result, the light ring R is radially offset outboard of a path defined by a radial sweep of the pointer  14 . 
   The speedometer  12  will now be described in greater detail. The dial  20  generally defines a passage  22  for accepting the pointer  14  therethrough. The pointer  14  defines a mounting end  24  and a pointing end  26 . The mounting end  24  may be disposed within a hub  30  attached to a motor  32 . A shaft  33  extends from the motor  32 , through the hub  30  and into the mounting end  24  of the pointer  14 . The motor  32  may communicate with a vehicle module (not shown) and transmit rotational motion onto the pointer  14  indicative of vehicle speed. In one example, the pointer  14  may be a bright or reflective color such as a florescent material or chrome. As shown, the hub  30  is located inboard of the dial  20  giving the pointer  14  a hubless appearance. Furthermore, the passage  22  is radially offset a minimal distance from the outer diameter of the mounting end  24  of the pointer  14 . 
   In one method of assembly, the hub  30  may be advanced onto the shaft  33  extending from the motor  32 . The dial  20  may then be secured to the speedometer  12  by conventional methods. Next, the mounting end  24  of the pointer  14  may be coupled relative to the hub  30  by inserting the mounting end  24  of the pointer  14  through the dial passage  22 . The mounting end  24  of the pointer  14  may then be advanced in a downward direction (as viewed from  FIG. 3 ) until a portion of the proximal end of the shaft is inserted partially into the pointer  14 . The dial  20  includes an appliqué  34  disposed on an outer face. The appliqué  34  may include indicia  36 , markings and/or other graphics. A lens  38  may enclose the speedometer  12 . 
   A light diverting member  40  is arranged around the dial  20 . The light diverting member  40  is adapted to receive light from a light source  42  and direct a first portion of the light  46  generally away from the dial  20  (light ring R) and a second portion of the light  48  generally toward the dial  20  (floodlight F). The light source  42  may include any suitable light source such as a light bulb or light emitting diode (LED) for example. In the exemplary speedometer  12  shown, the light source  42  includes a series of LEDs arranged in a circular pattern inboard of the dial  20 . The series of LEDs may include any number of LEDs, such as between four and eight sufficient to emit enough light for the light ring R and floodlight F to be properly observed by a user. 
   A cover member or mask  50  is arranged adjacent to the light diverting member  40 . The mask  50  is adapted to obscure view of the light diverting member  40  from a vehicle operator and block any stray light from the light diverting member  40 . In one example, the mask  50  may extend from the dial  20  at an angle and define a radial flange  54  on an outer end. The mask  50  may be unitary and configured to extend inboard a distance beyond the light diverting member  40 . Explained differently, the mask  50  may define an inner diameter D 1  less than an inner diameter D 2  of the light diverting member. 
   The light diverting member  40  generally defines a unitary prism having a circular footprint. It is appreciated that the light diverting member  40  may define other shapes such as, but not limited to, semi-circular. In addition, the light diverting member  40  may alternatively define multiple pieces or sections. The light diverting member  40  includes an inboard and outboard longitudinal portion  60  and  62 , respectively, connected by an intermediate angled portion  66 . In one example, the inboard and outboard longitudinal portions  60  and  62  are parallel to each other and transverse from a plane defined by the dial  20 . An outer angled portion  70  extends from the outboard longitudinal portion  62 . 
   The light diverting member  40  includes three light reflecting surfaces  72 ,  74  and  76 . The intermediate angled portion  66  defines the first and second light reflecting surfaces  72  and  74 . The outer angled portion  70  defines the third light reflecting surface  76 . Light emitted from the light source  42  enters the light diverting member  40  in a first direction. For illustrative purposes, a pair of exemplary light paths will be described. A first light path L 1  travels through the inboard longitudinal portion  60  and reflects off the first light reflecting surface  72 . The reflected light then reflects off the second light reflecting surface  74 . Once reflected off the second reflecting surface  74 , the first light path L 1  travels through the outboard longitudinal portion  62  until contacting the third light reflecting surface  76 . The third light reflecting surface  76  reflects the light out of the light diverting member  40  at a first light exit area  84  and onto the pointer  14  and the dial  20  (floodlighting F). 
   A second exemplary light path L 2  will now be described. The second light path L 2  travels through the inboard longitudinal portion  60  and reflects off the first light reflecting surface  72 . The reflected light then reflects off the second light reflecting surface  74 . Once reflected off the second reflective surface  74 , the second light path L 2  exits the light diverting member  40  at a second light exit area  86  and shines generally away from the dial  20  (light ring R) and such that a user may view it. Light ring R generally denotes the outer boundary of the indicia and defines the area within which a user should direct his or her attention when viewing the dial  20 . 
   While the invention has been described in the specification and illustrated in the drawings with reference to various embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention as defined in the claims. For example, while the drawings and related discussion are specifically directed toward a radial dial, the same may be applied to a gauge arranged in another pattern, such as linear. Furthermore, the mixing and matching of features, elements and/or functions between various embodiments is expressly contemplated herein so that one of ordinary skill in the art would appreciate from this disclosure that features, elements and/or functions of one embodiment may be incorporated into another embodiment as appropriate, unless described otherwise above. Moreover, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment illustrated by the drawings and described in the specification as the best mode presently contemplated for carrying out this invention, but that the invention will include any embodiments falling within the foregoing description and the appended claims.