Abstract:
A remote control model car includes a rear suspension mechanism mounted in either side of the chassis. The chassis has a suspension body. The rear suspension mechanism includes a pivotal adjustment rod coupled to the lug of the suspension body, a pivotal arm mechanism, a hub mechanism, and a shock absorber pivotably secured to the arm mechanism and the suspension body. This arrangement allows for a smooth, simple, and reliable wheel angle adjustment.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a rear suspension mechanism for a model jeep with improved characteristics. 
     BACKGROUND OF THE INVENTION 
     Conventionally, remote control model cars are classified as remote control model racing cars for planar ground or model jeeps for uneven terrain (as the subject matter of the invention). Hence, the construction of the latter is required to be more robust and capable of easily being adjusted. Typically, two rear wheels are driven by a drive source through a transmission mechanism. Further, a shock absorber is provided and associated with each rear wheel. Each of the front and the rear sides of wheel may be positioned at an angle with respect to the ground. An offset angle is defined as the angle of the rear transmission axle with respect to rear wheel in a horizontal plane. An inclined angle is defined as the angle of the surface of rear wheel with respect to a vertical plane. In general, the surface of rear wheel is inclined towards an inner side of a model jeep for increasing the centripetal force while manipulating the model jeep. 
     A schematic rear plan view in partial section of a conventional remote control model jeep is shown in FIG. 5. A transmission seat  17  is provided on chassis  1 . A suspension body  11  is provided adjacent transmission seat  17 . A bar on suspension body  11  is coupled to the top of hub mechanism  8 . An arm mechanism  3  under the suspension body  11  is coupled to the bottom of the hub mechanism  8 . A transmission rod  18  is passed through the universal joint  181  and the hub mechanism  8  to couple the transmission seat  17  and hub  19  of wheel together. Following is a description of the adjustment of the inclined angle and offset angle. As to the adjustment of the inclined angle, it is required that the bar is replaced, and hence it is inconvenient. As to the adjustment of the offset angle, a fastening block in the suspension body  11  is detached and replaced with a new fastening block. Fastening block is inserted through the shaft coupled to the suspension body  11 . Thus the angle of the shaft may be adjusted. That is, the angle. of the shaft is determined by the positions of two end holes of fastening block. At this time, the angle of the shaft is identical to that of offset angle. In view of above, the adjustment of the offset angle is much more inconvenient. Further, the normal operation of the arm mechanism  3  may be adversely affected. As a result, most users only set up the model jeep in a less precise manner. Thus such model jeep does not perform well in a difficult terrain which in turn dissatisfies an enthusiastic user. 
     Thus, it is desirable to provide an improved rear suspension mechanism for remote control model jeep in order to overcome the above drawbacks of the prior art. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a rear suspension mechanism for a remote control model car for effecting a smooth, simple, and reliable wheel angle adjustment. Further, it is possible to adjust the distance between two rear wheels and the length of the model jeep. 
     To achieve the above and other objects, the present invention provides a remote control model car having a chassis with a rear suspension mechanism mounted in either side of the chassis, the chassis having a suspension body in the rear including a transmission seat, a coupling on either side of the transmission seat coupled to a universal joint at the internal end of a transmission rod, a lug on either side of the upper portion of the suspension body, a first ear on either side of the lower part of the suspension body, a fastening block at either front or rear side, a shaft secured bet a second ear on either side of the fastening block, and a shaft secured between the first and the second ears, the rear suspension mechanism comprising a pivotal adjustment rod coupled to the lug of the suspension body, the adjustment rod including a center enlargement, two threaded rods on either side of the center enlargement, and two end joints such that the length of the adjustment rod is adjustable by adjusting the securing of the threaded rods and the end joints; a pivotal arm mechanism including two sleeves put on the shaft between the first and the second ears, each sleeve being abutted on one of the first and the second ears; a hub mechanism having an upper part coupled to the adjustment rod and a lower part coupled to the arm mechanism respectively, one end of the transmission rod being passed through the universal joint to couple to a joint of a pin mechanism, the other end of the pin mechanism formed as a bar passed through the hub mechanism, a bearing put on the bar of the pin mechanism, the bearing placed within the hub mechanism the bar of the pin mechanism passed through the hub mechanism, a fastener sleeved on the bar and secured to a rear wheel, a pair of parallel adjustment members at the external ends of the arm mechanism being threadedly secured to a bolt having a ball-shaped head secured in one of two fork members of the hub mechanism; and a shock absorber having a bottom end pivotably secured to an engagement member of the arm mechanism and a top end secured to the suspension body. 
     The above and other objects, features and advantages of the present invention will become apparent from the following detailed description taken with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective exploded view of a rear suspension mechanism for a remote control model jeep according to the invention; 
     FIG. 2 is an exploded view of the FIG. 1; 
     FIG. 3 is a schematic top plan view of the FIG. 1 model jeep illustrating the adjustment of offset angle; 
     FIG. 4 is a schematic rear plan view in portion section of the FIG. 1 illustrating the adjustment of inclined angle; and 
     FIG. 5 is a rear plan view with some parts shown in cross section of the rear suspension mechanism for a conventional remote control model jeep. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to FIGS. 1 through 4, there is shown a remote control model jeep incorporating a rear suspension mechanism in accordance with the invention. A suspension body  11  is provided in the rear of the chassis  1 . A transmission seat  17  is provided in the suspension body  11 . A coupling  171  on either side of the transmission seat  17  is coupled to a universal joint  181  at the internal end of the transmission rod  18 . A lug  12  on either side of the upper part of suspension body  11  is coupled to the internal end of the adjustment rod  2 . The lug  12  includes holes  121 . Adjustment rod  2  has a center enlargement portion  22 , two threaded rods  21  on either side of the center enlargement portion  22 , and two joints  23  and  24  on both ends. The length of the adjustment rod  2  may be adjusted by adjusting the threading lengths of the joints  23  and  24  to the threaded rod  21 . A first ear  13  is provided on either side of the lower part of the suspension body  11 . A second ear  15  is provided on either side of the fastening block  14 . A shaft  16  is secured between first and second ears  13  and  15 . Both arm mechanism  3  and adjustment rod  2  may pivot. Two sleeves  31  of the arm mechanism  3  are put on the shaft  16  between the ears  13  and  15 . Each sleeve  31  is abutted on either ear  13  or ear  15 . The upper and lower parts of a hub mechanism  4  are coupled to the adjustment rod  2  and arm mechanism  3  respectively. One end of a transmission rod  18  is passed through the universal joint  182  to couple to a joint  191  of the pin mechanism  19 . The other end of the pin mechanism  19  is formed as a bar  192  which is passed through the hole  41  of the hub mechanism  4 . A bearing  193  is put on the bar  192  of the pin mechanism  19 . Bearing  193  is placed within the hole  41  of the hub mechanism  4 . Bar  192  of the pin mechanism  19  is passed through the hub mechanism  4 . A fastener  194  is sleeved on the passed bar  192  and is positioned in the hub of the wheel  5 . A nut  195  is secured to the external end of the fastener  194  such that the wheel  5  may rotate about the pin mechanism  19 . A pair of parallel adjustment members  38  are provided at the external ends of the arm mechanism  3 . A threaded hole is formed at one end of the parallel adjustment member  38  for threadedly securing to a threaded shank  33  of bolt  32 . Ball-shaped head  34  of bolt  32  is placed in a threaded hole  43  of one of two fork members  42  at the lower portion of hub mechanism  4 . Ball-shaped head  34  of bolt  32  is further secured by a washer  44  and nut  45 . A shock absorber  6  has a bottom end pivotably secured to an engagement member  35  of the arm mechanism  3  and a top end secured to one of the holes  101  of the projecting member  10 . Likewise, a plurality of holes  47  are formed at each of a pair of lugs  46  on the top of the hub mechanism  4 . A threaded hole  36  is provided at the internal side of the arm mechanism  3 . A screw  37  is secured in the threaded hole  36  wherein the bottom end of the screw  37  is projected from the underside of arm mechanism  3 . Hence, the bottom end of the screw  37  is first in contact with the chassis  1  for being held thereto when the arm mechanism  3  is about to contact the top of the chassis  1 . Then the wheel  5  is moved up together with the arm mechanism  3 . In turn, the frame of the model jeep is lowered to prevent the arm mechanism  3  from contacting the ground. This is a safe mechanism. An opening  351  of the engagement member  35  is pivotably secured to the bottom end of the shock absorber  6  by inserting a pin through a plurality of holes  352 . Hence, it is possible to adjust the tightness of the shock absorber  6  with respect  15  to the arm mechanism  3  by selecting one of the plurality of holes  352 . 
     Referring to FIG. 3 specifically, the angle adjustment of the offset angle may be effected by adjusting the positions of two bolts  32 . In detail, nut  45  is loosened. Then, bolt  32  is adjusted to adjust the length of the arm mechanism  3 . As a result, the angle adjustment of the offset angle may be carried out by simply using a box end wrench. Thus, it is very convenient. 
     Referring to FIG. 4 specifically, the angle adjustment of the inclined angle may be effected by adjusting the adjustment rod  2 . In detail, a user may turn the nut  45 , or as stated above, select a suitable hole  352  to secure the shock absorber  6  to the arm mechanism  3 . Thus a more flexible and effective adjustment of the inclined angle is carried out. Further, it is possible to adjust the distance between two rear wheels by turning the bolt  32  for adjusting the length of the arm mechanism  3 . Furthermore, it is possible to adjust the length of the model jeep by adding or removing a plurality of washers  311  between the sleeves  31  and first ears  13  wherein washers  311  are put on the shaft  16 . 
     While the invention has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope and spirit of the invention set forth in the claims.