Abstract:
The present invention may be used for illuminating the terrain in the proximity of the axles, differential, wheels and tires for off-road vehicles. An access cover of differential gear axle housing may have lateral ribs formed as part of the cover outside surface. A recess may be formed by recess walls as an element of the lateral ribs. A light emitting device may be mounted in the recess and may be electrically connected through a port in the recess walls to an electrical power source controllable from an off-road vehicle.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to lighting systems for off-road land vehicles for illuminating the terrain in proximity of the axles and wheels of the vehicles for night viewing of terrain obstacles. The new lighting system is incorporated into the differential housing for drive wheels of the off-road vehicles. 
     Head lamps or lights, fog lights, and back-up lights may be incorporated on or in the body/chassis of land vehicles, including off-road vehicles such as heavy duty pickup trucks, trucks and equipment, and sport utility vehicles (SUVs). These off-road vehicles often have extra ground clearance, sturdy tires, and front and rear locking differentials with housings. Off-road vehicles may often include four wheel drive vehicles. One example of use of off-road vehicles is for Rock Crawling for which vehicles are typically modified with larger than stock tires, suspension components that allow greater axle articulation and terrain separation distance and changes in the differential gear ratio in order to provide the ideal high torque/low speed operation for traversing obstacles. A rock crawler vehicle may have a spotter or an assistant who will go on foot along side of or in front of the vehicle to provide information to the driver on obstacles or areas of terrain that the driver may not be able to see. 
     For night operation or driving, whether for Rock Crawling or other rough terrain vehicle use, there is often a need for illumination in the proximity of the axles, differentials and wheels/tires for a driver or spotter to view obstacles in order for a vehicle to progress in an off-road environment. There is a need for mounting of lamps, light-emitting devices and the liked under land vehicles for night off-road operation. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to systems for illuminating the terrain in the proximity of the axles, differential, wheels and tires for off-road vehicles. An access cover of differential gear axle housing may have lateral ribs formed as part of the cover outside surface. A recess may be formed by recess walls as an element of the lateral ribs. A light emitting device may be mounted in the recess and may be electrically connected through a port in the recess walls to an electrical power source controllable from an off-road vehicle. 
     These and other features, aspects and advantages of the present invention will become better understood with reference to the following drawings, description and claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a perspective view of an off-road vehicle with modified suspension components and added differential gear housing lighting according to an embodiment of the invention; 
         FIG. 2  illustrates an elevation view of an access cover of differential gear housing with lighting system components according to an embodiment of the invention; 
         FIG. 3  illustrates a perspective elevation view of an access cover of differential gear housing with lighting system components according to an embodiment of the invention; 
         FIG. 4  illustrates a perspective fragmentary sectional view of an access cover of a differential gear housing with lighting, batteries and wiring according to an embodiment of the invention; 
         FIG. 5  illustrates a perspective elevation view of a pinion shaft and differential gear axle housing with lighting system components according to an embodiment of the invention; 
         FIG. 6  illustrates an elevation view of a pinion shaft and differential gear axle housing with lighting system components according to an embodiment of the invention; 
         FIG. 7  illustrates a perspective elevation view of an access cover of differential gear axle housing with a camera according to an embodiment of the invention; 
         FIG. 8  illustrates a perspective elevation view of an access cover of differential gear axle housing with a camera according to an embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION 
     The following detailed description represents the best currently contemplated modes for carrying out the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention. 
     Referring to  FIGS. 1 through 4 , a lighting system  10  for the underbody of an off-road vehicle  12  may have components mounted in an access cover  20  of a differential gear axle housing  14 . The access cover  20  may have recesses  24  formed in portions of the structure at an outside surface  21  that also are lateral ribs  22  that are used to reinforce the access cover  20 . Depending on the type of illumination or light emitting device  40  used, the recesses  24  may generally be cylindrical or other suitable form. The recesses  24  illustrated in  FIGS. 2 and 3  are internally cylindrical with recess walls  26  formed to mate with the lateral ribs  22  adjacent an elongated generally centrally positioned receptacle  28  or compartment with side wall  30  and bottom  32  contoured to the curvature of the access cover  20 . The receptacle  28  has a cover  34  fastened to enclose the electrical wiring  42  and batteries  44  for powering the light emitting devices  40 . The cover  34  may be used as a name plate. 
     The recesses  24  with light emitting devices  40  may be sealed at outer edge  36  to inhibit entry of liquids, such as water, and debris from causing damage or failure of the lighting system  10  components. The exterior walls  26  may have ports  38  open to the receptacle  28  for electrical connections between the light emitting devices  40  and the power source  44 . The application and removal of electrical power may be controlled remotely by a switch or control system (not shown) positioned in a console or dash board for ease of control by a driver of the off-road vehicle  12 . The power control may be by wiring connection or a wireless remote control device (not shown) to a controller  80  positioned in the receptacle  28 . The connecting wiring (partially shown) between the lighting system  10  components in the access cover  20  may be routed and attached to structural elements of the off-road vehicle  12  similar to that understood for land vehicle wiring for other electronic components. The power source  44  is illustrated as a battery; however, the light emitting devices  40  may also be connected by cables  42  to a connector  48  that is then connected to the vehicle  12  electrical system (not shown). 
     Referring to  FIGS. 5 and 6 , the pinion shaft and differential gear axle housing  14  may have light emitting sources  40  with electrical wiring  42  attached to lateral ribs  50  adjacent to the pinion shaft housing  16  component. An attachment bracket  52  may be used to retain a connector  46  or other power source. The same wiring and control system as used to control the lighting system  10  components on the access cover  20  may be used to operate the components illustrated in  FIGS. 5 and 6 . The light emitting devices  40  may be mounted in generally cylindrical housings  54  that are open at one end  56  and closed at the opposite end  58 . The lighting housings  54  may be oriented to direct light generally parallel to the pinion shaft housing  16  axis or at an angular orientation to the housing  16 . Two lighting housings  54  are illustrated in  FIG. 5  oriented at approximately right angles to one another. 
     Referring to  FIGS. 1 through 6 , the light emitting devices  40  generally appear to be directed to the rear or the front of a vehicle  12  depending on whether the differential housing  14  is part of a rear axle (not shown) or a front axle  64  and the illumination will be generally parallel to a pinion shaft axis (not shown). However, light emitting devices  40  may be produced in a variety of light emitting beam forms. For example, the light beam may spread outwardly from the source in a broad cone shape or may be a narrower beam that is directed at an angle relative to the axis of the recess  24  or housing  54 . In the case of the access cover  20  recesses  24  the recess walls  26  may have slanted ends  25  relative to an imaginary plane parallel to the access cover  20  flange to allow orientation of light emitting devices  41  to direct light beams to areas of interest at the front or rear portion of the vehicle  12 . Also in the case of the housing  54 , they may be rotated relative to the longitudinal axis to direct a light beam other than parallel to the pinion shaft housing axis. 
     With desired orientation of the light emitting devices  40  an off-road vehicle  12  driver may be able to negotiate rough terrain at night in order to travel. In extremely rough terrain a spotter may use the lighting system  10  at night to aid a driver in traveling in the vehicle. The lighting system  10  may be incorporated in recreational and military vehicles. Special light emitting devices  40  may be incorporated, for example, infra-red, for use in military applications to avoid enemy detection and to aid the driver/user. An example of military use may be light emitting devices requiring night vision capability to be seen that assist vehicles in a convoy to follow closely at night and yet avoid detection by an enemy. 
     Referring to  FIGS. 7 and 8 , a camera  70  may be mounted on the access cover  20  positioned to view the terrain adjacent to the differential housing  14 . The camera  70  may be a digital camera with a digital cable  72  connected to a display (not shown) in the vehicle driver field of view to allow use without the driver having to exit the vehicle  12 . The camera  70  may also have a memory device for storage of images and a wireless image transmitter to transmit images to a remote receiver. 
     While the invention has been particularly shown and described with respect to the illustrated embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and details may be made therein without departing from the spirit and scope of the invention.