Abstract:
The present invention is a vehicle lift. In particular, the present invention is directed to a vehicle lift that can be mounted to the rear of a vehicle or be used as a stand-alone device to lift vehicles. The preferred embodiment comprises a vehicle platform supported by a first lifting arm and a second lifting arm. The lifting arms are mounted to shafts mounted on gears. Each shaft and lifting arm has a corresponding castellated end. A star plate attaches to the shaft, fitting within the castellated ends, and joins the shaft and lifting arm. A chain engages the gears and comprises two segments joined by adjustment rods. The rods adjust chain tension and gear timing. The chain is connected to an arm of a drive. When the arm extends, it moves the chain that rotates the gears and lifting arms and lifts the platform.

Description:
TECHNICAL FIELD 
       [0001]    The present invention is a vehicle lift. In particular, the present invention is directed to a vehicle lift that can be mounted to the rear of a vehicle, such as a passenger vehicle, truck, or recreational vehicle, or be used as a stand-alone device to lift vehicles such as mobility scooters, motorcycles, all-terrain vehicles and scooters. 
       BACKGROUND ART 
       [0002]    A number of different vehicle lifts exist. However, these lifts often are heavy and difficult to operate and require significant space for operation extending behind a master vehicle, such as an RV or truck. Said lifts need sizable power plants to lift vehicles. Many lifts are either cable or light duty gear driven that are either not powerful enough to lift heavier loads or do not allow for a variety of cargo. These lifts also require complex locking mechanisms to secure the lifted vehicles in place. Accordingly, a vehicle lift is needed that is lockable, operates in a more confined space and makes an efficient use of lifting power. 
       SUMMARY OF THE INVENTION 
       [0003]    The present invention is a vehicle lift. In particular, the present invention is directed to a vehicle lift that can be mounted to the rear of a vehicle or be used as a stand-alone device to lift vehicles. The preferred embodiment comprises a vehicle platform supported by a first lifting arm and a second lifting arm. The lifting arms are mounted to shafts mounted on gears. Each shaft and lifting arm has a corresponding castellated end. A star plate attaches to the shaft, fitting within the castellated ends, and joins the shaft and lifting arm. A chain engages the gears and comprises two segments joined by adjustment rods. The rods adjust chain tension and gear timing. The chain is connected to an arm of a drive. When the arm extends, it moves the chain that rotates the gears and lifting arms and lifts the platform. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]    The objects and features of the present invention, which are believed to be novel, are set forth with particularity in the appended claims. The present invention, both as to its organization and manner of operation, together with further objects and advantages, may best be understood by reference to the following description, taken in connection with the accompanying drawings. 
           [0005]      FIG. 1  is a perspective side view of a preferred embodiment of the invention with a shop stand configuration; 
           [0006]      FIG. 2   a  is a partial cut-away view of a preferred embodiment of the invention with a vehicle hitch configuration in the raised position; 
           [0007]      FIG. 2   b  is a rear perspective view of a preferred embodiment of the cam lock in the locked position; 
           [0008]      FIG. 3  is a partial exploded side view of a preferred embodiment of the lifting arm and shaft with castellated ends and star plate; 
           [0009]      FIG. 4  is a front perspective view of a preferred embodiment of a lifting arm bolted to a shaft with a star plate; 
           [0010]      FIG. 5  is a front view of a preferred embodiment of a star plate; 
           [0011]      FIG. 6  is a partial rear perspective view of a preferred embodiment of the locking bar and cam lock in the locked position; 
           [0012]      FIG. 7  is a perspective view of a preferred embodiment of the cam lock; 
           [0013]      FIG. 8  is a perspective view of a preferred embodiment of the adjustment rod; and, 
           [0014]      FIG. 9  is a partial exploded perspective view of a preferred embodiment of the invention with a vehicle mount configuration. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0015]    The following description is provided to enable any person skilled in the art to make and use the invention and sets forth the best modes contemplated by the inventor of carrying out his invention. Various modifications, however, will remain readily apparent to those skilled in the art, since the general principles of the present invention have been defined herein specifically to provide a vehicle lift. 
         [0016]    Referring now to  FIG. 1 , a preferred embodiment of the vehicle lift is shown. The vehicle lift  10  is shown in a shop stand configuration with a vehicle platform  40  in the lowered position. A drive box  15  is mounted to a shop stand  100 . A first lifting arm  20  is mounted to a first shaft  30  extending from the drive box  15 . A second lifting arm  25  is mounted to a second shaft  31  extending from the drive box  15 . The lifting arms  20  and  25  are preferably inserted into platform mounts  33  on the underside of the platform  40 . The arms  20  and  25  support the vehicle platform  40 . The vehicle platform  40  in  FIG. 1  is shown as a single ramp. The platform  40  is preferably wide enough for a mobility scooter or a single motorcycle or scooter tire to roll onto the ramp  40 . The platform  40  is preferably long enough so both front and back tires of a mobility scooter or a motorcycle or other vehicle fit on the platform  40 . Alternately, the platform  40  can be wide enough for the side-by-side front or rear tires of a four-wheeled vehicle. Another alternative is that a second platform (not shown) could be placed on the lifting arms  20  and  25  with the first platform  40  to accommodate four-wheeled vehicles or other cargo. Another alternative for the platform  40  is that the platform  40  is configured to accommodate wheelchairs. 
         [0017]    Referring now to  FIG. 2   a , a partial cut-away view of the vehicle lift  10  is shown. The vehicle lift  10  is shown in a vehicle mount configuration with the vehicle platform  40  in a raised position. The embodiment shown in  FIG. 2   a  preferably is mountable to the rear of a vehicle such as a recreation vehicle (RV), a sport utility vehicle (SUV) or a truck or some other vehicle at the trailer hitch. As shown, a first lifting arm  20  and a second lifting arm  25  support the vehicle platform  40 . The first lifting arm  20  is mounted to first shaft  30  extending from the drive box  15 . The second lifting arm  25  is mounted to a second shaft  31  extending from the drive box  15 . The first shaft  30  is mounted to a first gear  34  and the second shaft  31  is mounted to a second gear  35 . 
         [0018]    A chain  50  connects the first and second gears  34  and  35  and engages the teeth of these gears  34  and  35 . The chain  50  preferably has two segments  52  and  54 . The segments  52  and  54  are preferably joined together by a first adjustment rod  60  and a second adjustment rod  61 . In the embodiment shown in  FIG. 2 , a linkage arm  72  of a hydraulic ram  70  is attached to the chain  50 . The hydraulic ram  70  is preferably a double acting single rod ended hydraulic cylinder where the pressure from the fluid is applied in both directions. The ram  70  shown is preferably a 3.1 160 amp 12 v electric over hydraulic motor and pump powered by a vehicle battery or AC power from an outlet. Preferably, the ram can be operated by local and/or remote controls. Alternately, an electric actuator or other type of drive can be used. The arm  72  is shown in an extended position in  FIG. 2   a  and preferably has a 10-inch stroke. Accordingly, when the linkage arm  72  of the hydraulic ram  70  extends, the arm  72  moves the chain  50  that rotates the gears  34  and  35 . The rotation of the gears  34  and  35  rotates the shafts  30  and  31  respectively. The rotation of the shafts  30  and  31  rotates the lifting arms  20  and  25  in the platform mounts  33 . The lifting arms  20  and  25  consequently move the vehicle platform  40 , preferably from a lowered position to a raised position. Preferably, the extension of the linkage arm  72  rotates the gears  34  and  35  one hundred and eighty degrees. Preferably, retraction of the arm  72 , rotates the gears  34  and  35  in the opposite direction and lowers the platform  40 . 
         [0019]    As shown in  FIG. 2   b , a locking bar  80  is shown in the locked position. As shown, a cam lock  36  is mounted behind the second gear  35  and around the second shaft  31 . The locking bar  80  is preferably mounted to the drive box  15  at pivot  81 . A preferred embodiment of the locking bar  80  and cam lock  36  arrangement is also shown in  FIG. 6 . 
         [0020]    A preferred embodiment of the cam lock  36  is shown in  FIG. 7 . As shown, the cam lock  36  preferably has a tapered or notched edge  37  so that the locking bar  80  can engage the cam lock  36  to prevent further rotation of the second gear  35  in one direction. Moreover, the tapered edge  37  of the cam lock  36  acts so that the locking bar  80  automatically engages once the cam lock  36  rotates to the notch  37 . Preferably, the position where the locking bar  80  engages the notch  37  corresponds to where the vehicle platform  40  is in the raised position. When the locking bar  80  is disengaged, it releases the cam lock  36  and allows rotation of the gear  35 . Thus, the platform  40  can be locked into a raised position as shown in  FIG. 2   a , e.g. for travel, and then subsequently lowered after the locking bar  80  is released, e.g. for arrival and removal of the cargo. 
         [0021]    Referring now to  FIG. 3 , a partial exploded view of a preferred embodiment of the first shaft  30  and first lifting arm  20  is shown. As shown, the lifting arm  20  preferably has a castellated or notched end  22 . The castellated end  22  of the lifting arm  20  is preferably tubular and slides over the first shaft  30  to mount. The first shaft  30  preferably has a castellated end  39  and a threaded plate  38 . A star plate  65  is preferably inserted into castellated end  22  of the lifting arm  20  and the castellated end  39  of the shaft  30  to align both castellated ends  22  and  39 . The star plate  65  is then preferably bolted or otherwise attached to the threaded plate  38  to affix the above parts together such that when the first shaft  30  rotates, it rotates the lifting arm  20  as well. A front view of a preferred embodiment of the first lifting arm  20  attached to the first shaft  30  by, inter alia, the star plate  65  is shown in  FIG. 4 . A front view of a preferred embodiment of the star plate  65  is shown in  FIG. 5 . Thus, the lifting arms  20  and  25  can be affixed to the shafts  30  and  31  and rotated to lift the vehicle platform  40 . 
         [0022]    Referring now to  FIG. 8 , a perspective view of a preferred embodiment of an adjustment rod  60  (or  61 ) is shown. The adjustment rod  60  preferably comprises a first adjustment bolt  62  with a left hand (LH) thread and a second adjustment bolt  67  with a right hand (RH) thread where each is threaded into an adjoining threaded bar nut  63 . Preferably, the first adjustment bolt  62  is threaded through a stop nut (LH)  64  and the second adjustment bolt  67  is threaded through a stop nut (RH)  69  and a jam nut (RH)  66 . The first adjustment bolt  62  and the second adjustment bolt  67  each have chain link ports  68  so that segments of the chain  50  can be attached to the adjustment rod  60  at each end via a master link (not shown). As discussed above, the chain  50  preferably comprises two segments  52  and  54  and two adjustment rods  60  and  61  preferably join the segments. By adjusting the adjustment bolts  62  and  67  into and out of the adjoining threaded bar nut  63  while the adjustment rod  60  is attached to the chain segments  52  and  54 , the tension and timing of the chain can be adjusted to reduce slippage and fit the chain  50  properly to the gears  34  and  35 . Furthermore, the arm  72  of the drive  70  can be attached to the adjustment rod  60  or  61  by placing an end of the arm  72  between the stop nut  69  and the jam nut  66  and tightening the nuts  69  and  66 . Thus, the arm  72  can move the chain  50  when attached to the adjustment rod  60  or  61 . 
         [0023]    Referring now to  FIG. 9 , a partial exploded view of a preferred embodiment of the invention  10  in a vehicle mount configuration is shown (except the chain is not shown for clarity.) In  FIG. 9 , the drive box  15  comprises a faceplate  29  to cover the gears  34  and  35  and other moving parts. The drive box  15  also further comprises hub mounts  28  to add stability to the gear assemblies. The drive box  15  shown in  FIG. 9  also comprises vehicle mounts  12  preferably for mounting the invention to the rear of a vehicle not shown. In a shop stand configuration, the vehicle mounts  12  would preferably be replaced with the shop stand  100  shown in  FIG. 1  and the drive box  15  would be mounted thereto. 
         [0024]    Thus, an improved vehicle lift is described above that has an improved locking feature, an adjustable chain drive and rotating arms. In each of the above embodiments, the different positions and structures of the present invention are described separately in each of the embodiments. However, it is the full intention of the inventors of the present invention that the separate aspects of each embodiment described herein may be combined with the other embodiments described herein. Those skilled in the art will appreciate that adaptations and modifications of the just-described preferred embodiment can be configured without departing from the scope and spirit of the invention. Therefore, it is to be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described herein.