Abstract:
The present invention discloses an apparatus for propelling the wheelchair that prevents a backward movement and helps the occupant rotate the wheel with less manual torque. The invention makes it possible for the disabled person to climb the sloped road with less manual force and without fear of dangerous backward slide.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to a wheelchair, more in particular, to an apparatus for powering a wheelchair. More specifically, this invention relates to a wheelchair having a hand-operable powering device, allowing the occupant to propel the drive wheel with less torque and even to climb the sloped road easily.  
         BACKGROUND OF THE INVENTION  
         [0002]    Wheelchairs typically consist of a chair frame disposed between two sets of rear and front wheels. The rear wheel, which acts as the drive wheel, is engaged directly by the occupant&#39;s hands to propel the chair.  
           [0003]    The disabled occupant sits on the wheelchair and moves wherever he wants to go by propelling the ring that is mounted about the same axis of rotation as the drive wheel.  
           [0004]    For instance, U.S. Pat. Nos. 6,112,837 and 6,095,747 disclose techniques to implement a wheelchair for the disabled person.  
           [0005]    In the meanwhile, there is a shortcoming in the traditional wheelchair especially when the disabled occupant tries to climb the sloped road since he needs to supply more torque for propelling the wheel by his arms.  
           [0006]    Furthermore, it is even more difficult to cross over a bump with a slope for the disabled occupant since the wheelchair tends to move backward due to the slope of the bump.  
         BRIEF SUMMARY OF THE INVENTION  
         [0007]    In view of these problems, there is a need in the art for a wheelchair that is not subject to these limitations.  
           [0008]    Accordingly, it is an object of the present invention to provide an apparatus for propelling the wheelchair such that the disabled person sitting on the wheelchair easily propels the wheel with less manual torque even when he climbs the sloped road.  
           [0009]    It is further an object of the present invention to provide an apparatus for propelling the wheelchair such that the disabled person sitting on the wheelchair avoids the unintentional backward movement of the chair due to the slope of a road or a bump.  
           [0010]    In accordance with a broad aspect of the present invention, provided is an apparatus for propelling the wheelchair.  
           [0011]    The apparatus for propelling the wheelchair comprises a multiple of pulleys with wires for reducing the level of torque that is manually provided by the disabled person and clamps for rotating the wheel without the backward movement. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]    Further features of the present invention will become apparent from a description of the wheelchair with the propelling apparatus, taken in conjunction with the accompanying drawings of the preferred embodiment of the invention, which, however, should not be taken to be limitative to the invention, but are for explanation and understanding only.  
         [0013]    In the drawings:  
         [0014]    [0014]FIG. 1 is a schematic bird&#39;s-eye-view illustrating a preferred embodiment of the apparatus for propelling the wheelchair in accordance with the present invention.  
         [0015]    [0015]FIG. 2 is a schematic side-view illustrating a preferred embodiment of the apparatus for propelling the wheelchair in accordance with the present invention.  
         [0016]    [0016]FIG. 3 is a schematic plan-view illustrating a preferred embodiment of the apparatus for propelling the wheelchair in accordance with the present invention.  
         [0017]    [0017]FIG. 4 is a schematic front-view illustrating a preferred embodiment of the apparatus for propelling the wheelchair in accordance with the present invention.  
         [0018]    [0018]FIG. 5 is a schematic diagram illustrating the magnified side-view of the apparatus for propelling the wheelchair in accordance with the present invention.  
         [0019]    [0019]FIG. 6 is a schematic diagram illustrating the clamp comprising the apparatus for propelling the wheelchair in accordance with the present invention.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0020]    Preferred embodiments in accordance with the present invention will be explained in detail with reference to the accompanying drawings.  
         [0021]    [0021]FIG. 1 is a schematic diagram illustrating the propelling apparatus for the wheelchair in accordance with the present invention.  
         [0022]    The apparatus for propelling the wheelchair comprises a first roller  40  and a holding frame  20  for the central axis wherein one end is aligned with the central axis  14  of the wheel and the other end is assembled with a body handler  13  of the wheelchair.  
         [0023]    Further, one end of the lever  30  is inserted and assembled with the axis  14  of the wheel in such a way that the lever  30  moves back and forth along the circle with the axis  14 .  
         [0024]    One end of a holding frame  60  for a second roller  70  is also tied to the central axis  14  for the circular movement.  
         [0025]    The holding frame  60  for a second roller  70  is also tied to a holding frame  90  for a clamp  100 .  
         [0026]    The one side of the holding frame  20  for the central axis now acts as a hinge. The clamp  100  is implemented in a slanted manner such that the clamp touches the handle  12  and experiences the frictional force against the handle  12  when the handle  12  of the wheelchair moves backward.  
         [0027]    A first wire  50  is installed such that the first wire  50  is fixed to one end of the lever  30  in contact with a first roller  40  and simultaneously to the holding frame  20  for the central axis.  
         [0028]    A second wire  200  is installed such that the second wire  200  is fixed to one end of the holding frame  90  for the clamp  100  and simultaneously to the backside of the clamp  100 .  
         [0029]    As a preferred embodiment in accordance with the present invention, a restoring material  80  can be applied such that the holding frame  60  for a second roller and the holding frame  90  for the clamp recover to the original position after the displacement.  
         [0030]    When the occupant sitting on the chair wants to climb the sloped road, he pushes the lever  30 . Then a second roller  70  moves in the same direction with the lever  30  through a first wire  50 .  
         [0031]    As a consequence of the simultaneous movement of the holding frame  60  of a second roller, the clamp  100 , which is fixed by a second wire  200 , moves and becomes in contact with the handle  12  of the wheelchair.  
         [0032]    In this case, the holding frame  90  for the clamp  100  moves together with the holing frame  60  for a second roller. Consequently, the clamp  100  exerts a force on the handle and makes the handle  12  rotate.  
         [0033]    After a pre-defined amount of movement of the holding frame  60  for a second roller and holding frame  90  for clamp, they moves back to their initial position. Simultaneously, the lever is positioned at the original position via a first wire  50  due to a restoring material comprising at one side of the holding frame  90  of the clamp.  
         [0034]    As a preferred embodiment of a restoring material in accordance with the present invention, a spring can be employed.  
         [0035]    As the clamp  100  installed at the holding frame  90  gets off from the handle  12 , the handle  12  of the wheelchair tends to rotate in a backward direction.  
         [0036]    The clamp  100  prepared at one side of holding frame  20  of the central axis prevents the wheel from rotating in a backward direction because the clamp  100  is geared to the handle  12  of the wheelchair and is implemented in a slanted fashion with reference to the front direction.  
         [0037]    Furthermore, the restoring material installed at one end of the holding frame  90  exerts a restoring force on the clamp  100  and thereby prevents the wheel from rotating in a backward direction.  
         [0038]    Thereby, it becomes possible to lower the torque that occupant has to exert on the wheel by implementing a multiple number of rollers and wires comprising a pulley system as a propulsion device for a wheelchair.  
         [0039]    It also becomes possible to prevent the wheelchair from dangerously sliding in a backward direction on a sloped road through a clamp exerting a frictional force on the handler due to the restoring force in accordance with the present invention.  
         [0040]    Although the invention has been illustrated and described with respect to exemplary embodiments thereof, it should be understood by those skilled in the art that various other changes, omissions and additions may be made therein and thereto, without departing from the spirit and scope of the present invention.  
         [0041]    Therefore, the present invention should not be understood as limited to the specific embodiment set forth above but to include all possible embodiments which can be embodies within a scope encompassed and equivalents thereof with respect to the feature set forth in the appended claims.