Abstract:
A movable and steerable device that has a platform with four wheel assemblies, any of which are both drivable and steerable. Different driving and steering options can make the device move in different directions and orientations. The driving can be done by a drive motor, forming a drive loop of material, such as chain, and a steering motor, also forming a steering loop. The different loops are attached to different sprockets on the device, which have different sizes, and therefore the different loops do not interfere with one another.

Description:
[0001]    This application claims priority from provisional application No. 61/436,294, filed Jan. 26, 2011, the entire contents of which are herewith incorporated by reference. 
     
    
     BACKGROUND 
       [0002]    Roving deck wheels can be used to move along a stage, e.g., on tracks, or in steerable directions. These may be used during a stage performance, or to hold materials for a stage performance. 
       SUMMARY 
       [0003]    The present application describes a custom movable wheel assembly for making roving deck units of various configurations, along with driving and steering assemblies for the wheel assembly. 
         [0004]    According to embodiments, the wheel has both drive and steering, both driven by sprockets, using chain loops over individual gear-motors that are battery powered and remote controlled. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]      FIG. 1  shows a front on view of the Rover wheel assembly on a platform; 
           [0006]      FIG. 2  shows a bottom view of the Rover wheel assembly and platform; 
           [0007]      FIG. 3  shows a front view of a single Rover wheel, showing the gears; 
           [0008]      FIG. 4  shows a top view of the Rover wheel assemblies; 
           [0009]      FIG. 5  shows a close-up of the Rover wheel assembly; 
           [0010]      FIG. 6  shows an embodiment of the Rover wheel platform and the steering and drive mechanism for four-wheel steering; 
           [0011]      FIG. 7  shows an alternative embodiment with four wheel opposite steer; 
           [0012]      FIG. 8  shows an embodiment with two wheel steering; 
           [0013]      FIG. 9  shows an embodiment with no steering and 4 wheel drive; 
           [0014]      FIG. 10  shows an embodiment which operates along a track; 
           [0015]      FIG. 11  shows an embodiment with opposite steering; 
           [0016]      FIG. 11  a shows an embodiment with opposite steering and drive; 
           [0017]      FIG. 12  shows an assembly drawing of the Rover wheel assembly in a plan view; 
           [0018]      FIG. 13  shows a front view of the wheel assembly; 
           [0019]      FIG. 14  shows a close-up of the wheel portion of the Rover wheel assembly in a side view; 
           [0020]      FIG. 15  shows an alternative embodiment of the Rover wheel assembly. 
       
    
    
     DETAILED DESCRIPTION 
       [0021]      FIG. 1  illustrates the basic wheel assembly device that forms part of the rover wheel. The wheel assembly shows two wheels  101 ,  102 . In this embodiment, one of the wheels  100  is driven by a sprocket  102  that is itself driven by a gear drive  103 . The gear drive  103  drives the driven wheel based on driving force received from the main drive system. 
         [0022]      FIG. 2  shows the wheel assembly device from its bottommost portion, showing the wheel assemblies  100 ,  101 ,  200 ,  201 . Each of the wheels may include a gear drive, or alternatively only some of them might include a gear drive. For example in one embodiment, only one of the wheels includes a gear drive. The wheels such as  100 ,  101  are mounted to wheel supports  210 , via an axle  215 . The wheel supports  210  become part of the wheel support assembly device  220 . 
         [0023]      FIG. 3  illustrates the rover wheel assembly of  FIG. 1  from the rear, showing the wheels, and how the wheels are connected. The wheel  100  has an axle portion  300  on one side, with a driven sprocket  305  on its other side, driven by the sprocket connection  103 . The wheel  101  maybe completely free driven, and shows the axle connection  310  which allows the wheel  101  to freely move.  FIG. 3  also shows different driving sprockets  340  and  315 . One of the sprockets is used for steering the wheels to point the rover. The other sprocket is driven to drive the driving sprockets  305 . 
         [0024]      FIG. 4  shows a top view of the rover, showing a connection to the rover and the different driving sprockets. 
         [0025]      FIG. 5  shows him a detailed view showing the different sprockets, how the sprocket  305  is connected to the driven wheel  300 . 
         [0026]      FIGS. 6-11  show the way the wheel assemblies can be used to form a rover device. The basic rover device shown in  FIG. 6  includes a rover platform  600  having four wheel assemblies  610 , each of the wheel assemblies having generally the structure shown in  FIGS. 1 through 5 . 
         [0027]    In this embodiment, each of these wheel assemblies includes first and second wheels, one of which is driven in the other of which is free-rotating. Each wheel assembly also includes two concentric sprockets, including the larger steering sprocket  340  shown in  FIG. 3 , and the smaller driving sprockets  305  shown in  FIG. 3 , although the two sprockets can be reversed. 
         [0028]    In operation, the rover device uses two different motors, which can be attached to the platform  600 . The first motor  620  is connected via a steering chain  625  to the larger sprocket  340  on the wheel assembly  610 , and forms a complete loop connected to corresponding sprockets on wheel assemblies  611 ,  612  and  613 . In this embodiment, moving the steering motor causes the direction of the wheels to change in pointing direction. 
         [0029]      FIG. 6  shows an embodiment in which each of the wheel assemblies are pointed in the same direction. In  FIG. 6 , each of the wheel assemblies points in the same direction relative to an axis  615  which passes through the center line of the wheel assembly  610 . Moreover, those axes can be changed by the moving of the steering motor in either the forward or reverse direction. The steering motor can be, for example, a ⅛-¼ horsepower 24 V DC gear motor or servomotor. 
         [0030]    The chains can be driven by the chain drive as shown, over different idlers, with the steering chain  625  driven across idlers  626 , changing direction at each of the gears on the wheels, back to idlers  627 . In a similar way, the drive chain  635  can be driven across idlers  636 ,  637 . 
         [0031]    A drive motor is connected to the smaller sprockets on each of the wheels, in a similar way. The drive motor  630  is connected to a second chain  635  which connects to the sprocket  305  on the wheel assembly  610 , and also in the wheel assemblies  611 ,  612 ,  613  and  614 . Note that since the sprockets are of different sizes, the chains which drive these sprockets will always be at different locations. This prevents the sprockets and the chains from coming into contact with and possibly interfering with one another. 
         [0032]    The configuration of  FIG. 6  has the steering mechanism and a drive mechanism commonly attached to all the sprocket portions. This can be used to carry out a four wheel “crab” steering, which can allow the device to move in any path straight diagonal or curved. The centerline of the platform can stay parallel to the plaster line, as shown. 
         [0033]      FIG. 7  shows an alternative embodiment, which provides four-wheel, front-rear wheel opposite steer. The center line of the wagon follows the travel path as desired. In this embodiment, the drive motor  630  is connected to the all wheels, as in the first embodiment. However the steering motor  700  has two different outputs  710 ,  720  which are connected to the opposite wheels. The connection  710  causes the front wheels to point in the same direction, and causes the back wheels flowing in the same direction, however these directions are opposite. 
         [0034]      FIG. 8  shows an alternative embodiment which uses two wheel automotive style steering. In this embodiment, the steering drive  800  is connected only to the front wheels, while the rear wheels are constrained to stay straight, thereby providing automotive style steering. 
         [0035]    In other embodiments, the steering can be locked in any desired way, by maintaining the wheels in a locked direction as shown in  FIG. 9 . This constrains the wheels to only move straight along the wagon center line  900 . 
         [0036]    The steering can also be passive, as shown in  FIG. 10 , in which case the device may be guided along knives or other guiding devices maintained within guide grooves or holders such as  1010 . 
         [0037]      FIG. 11  shows an alternative embodiment with two wheel drive, and four wheel diagonal and equal and opposite steer. This moves in a straight path and rotates in place only. In this embodiment, the drive motor  630  connects only to two of the wheel assemblies  611 ,  612 . The steering motor  620  connects to all four wheels, however, causes the two diagonal wheels  610 ,  612  to face in the same direction, and the other two diagonal wheels  611 ,  613  to face in the same direction different. Other forms of driving and starting can be used. 
         [0038]      FIG. 11A  shows yet another modification, in which the drive motor  630  drives only the rear wheels, and the steering motor  620  drives only the front wheels. This provides a two rear wheel automotive style drive with two front wheel automotive style steering. 
         [0039]    Different drive connections of these types can be used. 
         [0040]      FIGS. 12 ,  13  and  14  show assembly diagrams of the wheel assembly device.  FIG. 12  shows a plan view, showing the wheels  1200 ,  1201 . The wheel  1200  is freely moving, while the wheel  1201  includes the drive gear  1202 . This wheel assembly is connected to a platform to form the rover as described above. 
         [0041]      FIG. 13  illustrates a front view of the wheel assembly, showing the wheels  1200   1201 , and the driving gear  1202 . In the  FIG. 13  embodiment, the gear  1202  is shown connected to the driven gear  1300 , which itself is connected via a driving shaft  1305  to sprocket  1310  that is driven by the chains as described herein. 
         [0042]      1311  illustrates the location of the chain drive loop to drive the wheels. The second chain drive loop is shown as  1321 , connecting to the other sprocket  1325  that connects to a bearing top plate  1330  which itself is connected to change the direction in which the wheels are steered. 
         [0043]      FIG. 14  shows a side view, showing one of the wheels  1200 , and also showing the sprockets and connections. 
         [0044]      FIG. 15  shows an alternative construction for the drive wheel assemblies according to an alternative embodiment. In  FIG. 15 , the wheel  1500  is shown held on a keyless bushing  1510 . The wheel itself can be moved by its connection at  1522 . The drive sprocket  1525  that includes the chain loop thereon shown generally as  1530 ,  1531 . The chain loop causes movement of the shaft  1520  which correspondingly moves the wheel. In a similar way, the wheel can be rotated as in the other embodiments by applying electromotive force to the sprocket  1535  via the chain loop shown as  1536 ,  1537 . 
         [0045]    Other embodiments are contemplated. For example, other ways of driving the individual devices can be used. For example, belts can be used instead of chains, and other kinds of materials can be used.