Precision direct drive mechanism for a power assist apparatus for a bicycle

Abstract

A power assist apparatus which includes a battery pack that connects with a motor housing with the battery pack being removably mounted on the frame of the bicycle and the motor housing being mounting on a mounting plate which is carried by one of the support wheels of the bicycle. The power assist apparatus is designed to not only assist in the manual operation of the bicycle but also as a sole source of power for the bicycle. The mounting plate is to be affixed to the frame of the bicycle upon the desired location being selected for the mounting plate. The motor assembly operates a drive gear, pulley or sprocket which connects to a driven gear, pulley or sprocket which is mounted in conjunction with one of the support wheels of the bicycle. The motor housing may be disconnectable from the mounting plate as also the battery pack is capable of being disengaged from the frame of the bicycle permitting the bicycle to be used as a conventional bicycle without the power assist apparatus. The motor assembly is indexed to the axle of the support wheel maintaining accurate alignment in all operating conditions and upon repeated engagements and disengagements of the support wheel from the bicycle frame.

What is claimed is:  
     
       1. In combination with a bicycle  wheeled vehicle, said bicycle  wheeled vehicle having a frame mounted on at least one support wheel, said support wheel being rotatable within a plane of rotation, said support wheel having an axle with said axle being mounted on said frame, said axle having a first axis of rotation which is perpendicular to said plane of rotation, a power assist apparatus to be mounted in conjunction with said bicycle  wheeled vehicle, said power assist apparatus comprising: 
       a driven gear mounted on said support wheel, said driven gear defining a rotational plane, said rotational plane being parallel to said plane of rotation, said driven gear having a center point, said center point coinciding with said first axis of rotation;  
       a motor assembly having an output shaft, said motor assembly being mounted on a mounting plate, said mounting plate being supportingly mounted on said axle, said axle being freely rotatable relative to said mounting plate, said mounting plate being fixed by securing means to said frame, said output shaft having a second axis of rotation, a drive gear mounted on said output shaft, said drive gear being in engagement with said driven gear, said drive gear being indexed to said axle by said second axis of rotation being parallel and spaced from said first axis of rotation, said motor assembly being electrically operated to rotate said drive gear and hence said driven gear which produces a power assist to rotate said support wheel; and  
       said mounting plate being pivotally adjustable to various angular positions about said first axis of rotation prior to being affixed to said frame by said securing means to one of said angular positions.  
     
     
       2. The combination as defined in  claim 1  wherein: 
       said driven gear comprising an external gear.  
     
     
       3. The combination as defined in  claim 1  wherein: 
       said securing means comprising a fastener, said fastener being removably mounted on said frame permitting said support wheel and said motor assembly to be disengaged from said bicycle  wheeled vehicle.  
     
     
       4. The combination as defined in  claim 1  wherein: 
       a battery pack which is to provide electrical power to operate said motor assembly, said battery pack being mounted on said frame, said battery pack being removable from said frame, whereby removing of said battery pack and disengaging of said motor assembly from said mounting plate reduces the overall weight of said bicycle  wheeled vehicle permitting said bicycle  wheeled vehicle to be operated as a conventional bicycle  wheeled vehicle not carrying excess weight.  
     
     
       5. The combination as defined in  claim 1  wherein: 
       said drive gear being in direct engagement with said driven gear.  
     
     
       6. In combination with a bicycle  wheeled vehicle, said bicycle  wheeled vehicle having a frame mounted on at least one support wheel, said support wheel being rotatable within a plane of rotation, said support wheel having an axle with said axle being mounted on said frame, said axle having a first axis of rotation which is perpendicular to said plane of rotation, a power assist apparatus to be mounted in conjunction with said bicycle  wheeled vehicle, said power assist apparatus comprising: 
       a driven gear mounted on said support wheel, said driven gear defining a rotational plane, said rotational plane being parallel to said plane of rotation, said driven gear having a center point, said center point coinciding with said first axis of rotation;  
       a motor assembly having an output shaft, said motor assembly being mounted on a mounting plate, said mounting plate being supportingly mounted on said axle, said axle being freely rotatable relative to said mounting plate, said mounting plate being fixed by securing means to said frame, said output shaft having a second axis of rotation, a drive gear mounted on said output shaft, said drive gear being in engagement with said driven gear, said drive gear being indexed to said axle by said second axis of rotation being parallel and spaced from said first axis of rotation, said motor assembly being electrically operated to rotate said drive gear and hence said driven gear which produces a power assist to rotate said support wheel; and  
       said mounting plate including an enlarged hole, said motor assembly including a motor housing, said motor housing being mounted within said enlarged hole in a close fitting relationship, a plurality of locking tabs mounted on said mounting plate, each said locking tab being separately movable between a locking position and an unlocking position, said locking position locking said motor housing on said mounting plate, said unlocking position permitting disengagement of said motor housing from said mounting plate.  
     
     
       7. The combination as defined in  claim 6  wherein: 
       a battery pack which is to provide electrical power to operate said motor assembly, said battery pack being mounted on said frame, said battery pack being removable from said frame, whereby removing of said battery pack and disengaging of said motor housing from said mounting plate reduces the overall weight of said bicycle  wheeled vehicle permitting said bicycle  wheeled vehicle to be operated as a conventional bicycle  wheeled vehicle not carrying excess weight.  
     
     
       8. In combination with a bicycle  wheeled vehicle, said bicycle  wheeled vehicle having two in number of support wheels with a frame interconnecting said support wheels, each said support wheel being mounted on an axle with there being a separate said axle for each said support wheel, a power assist apparatus to be mounted in conjunction with one said support wheel, said axle of said one said support wheel being mounted upon said bicycle  wheeled vehicle frame, said one said support wheel having a plane of rotation, said axle of said one said support wheel having a first axis of rotation which is perpendicular to said plane of rotation, said power assist apparatus comprising: 
       driven means mounted on said support wheel, said driven means having a center point, said center point coinciding with said first axis of rotation, said driven means being rotatable about said center point; and  
       a motor assembly having an output shaft, said motor assembly being mounted on a mounting plate, said mounting plate being supportingly mounted on said axle, said axle being freely rotatable relative to said mounting plate, said mounting plate being pivotally adjustable about said first axis of rotation to various angular positions defining several different mounting positions on said frame prior to being fixed by securing means to said frame to one of said angular positions, said output shaft having a second axis of rotation, a drive means mounted on said output shaft, said drive means being in engagement with said driven means, said drive means being indexed to said axle of said one said support wheel by said second axis of rotation which is parallel and spaced from said first axis of rotation, said motor assembly being electrically operated to rotate said drive means and hence said driven means which produces a power assist to rotate said one support wheel.  
     
     
       9. The combination as defined in  claim 8  wherein: 
       said securing means comprising a fastener, said fastener being removably mounted on said frame permitting said one said support wheel and said motor assembly to be disengaged from said bicycle  wheeled vehicle.  
     
     
       10. The combination as defined in  claim 8  wherein: 
       a battery pack which is to provide electrical power to operate said motor assembly, said battery pack being mounted on said frame, said battery pack being removable from said frame, whereby removing of said battery pack and disengaging of said motor assembly from said mounting plate reduces the overall weight of said bicycle  wheeled vehicle permitting said bicycle  wheeled vehicle to be operated as a conventional bicycle  wheeled vehicle not carrying excess weight.  
     
     
       11. The combination as defined in  claim 8  wherein: 
       said securing means comprising a fastener, said fastener being removably mounted on said frame permitting said support wheel and said motor assembly to be disengaged from said bicycle  wheeled vehicle.  
     
     
       12. The combination as defined in  claim 8  wherein: 
       said driven means comprising a driven pulley, said drive means comprising a drive pulley, a drive belt interconnecting said drive pulley and said driven pulley.  
     
     
       13. The combination as defined in  claim 8  wherein: 
       said driven means comprising a driven sprocket, said drive means comprising a drive sprocket, a chain interconnecting said drive sprocket and said driven sprocket.  
     
     
       14. In combination with a bicycle  wheeled vehicle, said bicycle  wheeled vehicle having two in number of support wheels with a frame interconnecting said support wheels, each said support wheel being mounted on an axle with there being a separate said axle for each said support wheel, a power assist apparatus to be mounted in conjunction with one said support wheel, said axle of said one said support wheel being mounted upon said bicycle  wheeled vehicle frame, said one said support wheel having a plane of rotation, said axle of said one said support wheel having a first axis of rotation which is perpendicular to said plane of rotation, said power assist apparatus comprising: 
       driven means mounted on said support wheel, said driven means having a center point, said center point coinciding with said first axis of rotation, said driven means being rotatable about said center point;  
       a motor assembly having an output shaft, said motor assembly being mounted on a mounting plate, said mounting plate being supportingly mounted on said axle, said axle being freely rotatable relative to said mounting plate, said mounting plate being fixed by securing means to said frame, said output shaft having a second axis of rotation, a drive gear mounted on said output shaft, said drive gear being in engagement with said driven gear, said drive gear being indexed to said axle by said second axis of rotation being parallel and spaced from said first axis of rotation, said motor assembly being electrically operated to rotate said drive gear and hence said driven gear which produces a power assist to rotate said support wheel; and  
       said mounting plate including an enlarged hole, said motor assembly including a motor housing, said motor housing being mounted within said enlarged hole in a close fitting relationship, a plurality of locking tabs mounted on said mounting plate, each said locking tab being separately movable between a locking position and an unlocking position, said locking position locking said motor housing on said mounting plate, said unlocking position permitting quick disengagement and quick reengagement of said motor housing from said mounting plate.