Patent Publication Number: US-6663539-B1

Title: Passive device for exercising legs of a user thereof

Description:
RELATED U.S. APPLICATIONS 
     Not applicable. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable. 
     REFERENCE TO MICROFICHE APPENDIX 
     Not applicable. 
     FIELD OF THE INVENTION 
     The present invention relates generally to an exercise device, and more particularly to a leg-exercising device. 
     BACKGROUND OF THE INVENTION 
     Conventional leg-exercising devices are generally cumbersome and are not adapted to serve as an adjunct to the physical therapy for rehabilitating a person&#39;s legs under treatment. 
     BRIEF SUMMARY OF THE INVENTION 
     The primary objective of the present invention is to provide a leg-exercising device which is compact and suitable for use in a limited floor space. 
     It is another objective of the present invention to provide a leg-exercising device which is adapted to rehabilitate a person&#39;s legs under treatment. 
     In keeping with the principle of the present invention, the foregoing objectives of the present invention are attained by a passive exercise device comprising a base on which two support frames, a motor, a transmission unit, and two driving units are mounted. Two footrests are driven by the two driving units to move up and down along the support frames, so as to bring about a training effect on a person&#39;s legs resting on the footrests. The person does not exert a force to activate or operate the exercise device. 
    
    
     The features and the advantages of the present invention will be more readily understood upon a thoughtful deliberation of the following detailed description of a preferred embodiment of the present invention with reference to the accompanying drawings. 
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     FIG. 1 shows a perspective view of the preferred embodiment of the present invention. 
     FIG. 2 shows an exploded view of the preferred embodiment of the present invention. 
     FIG. 3 shows a sectional view of the preferred embodiment of the present invention. 
     FIG. 4 shows a sectional schematic view of the preferred embodiment of the present invention in action. 
     FIG. 5 shows another sectional schematic view of the preferred embodiment of the present invention in action. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As shown in FIGS. 1-5, an exercise device embodied in the present invention comprises a base  14 , two support frames  10 , a motor  20 , a transmission gear  33 , a drive axle  34 , two sprocket wheels  16 , two driven chains  17 , and two footrests  11 . 
     The two support frames  10  are identical in construction with each other and are mounted on the base  14  side by side. The support frames  10  are provided at the bottom end with a fastening hole  102  for fastening a seat  101 . 
     The motor  20  is fastened with a motor mount  30 , which is located between the two support frames  10 . The motor mount  30  is provided with a horizontal through hole  31  corresponding in location to the fastening holes  102  of the two support frames  10 . The motor mount  30  is further provided with a fastening plate  22  which is in turn provided with a vertical through hole  23  in communication with the horizontal through hole  31  of the motor mount  30 . The motor  20  is provided with a locating plate  22  by means of which the motor  20  is mounted on the fastening plate  22  such that a motor spindle  21  is received in the vertical through hole  23 . A deceleration gear  211  is fastened to the free end of the motor spindle  21 . The motor mount  30  is fastened with the seats  101  of the support frames  10  by a plurality of screws  41 . 
     The transmission gear  33  is provided with a plurality of locating holes  332  and an axial hole  331  by which the transmission gear  33  is mounted on a drive axle  34 . The transmission gear  33  is located on the drive axle  34  by two locating bolts  40  which are received in the locating holes  332 . The transmission gear  33  is received in the horizontal through hole  31  of the motor mount  30  such that the transmission gear  33  is engaged with the deceleration gear  211  of the motor spindle  21 , as shown in FIGS. 4 and 5. The drive axle  34  is provided at both longitudinal ends with a retaining block  341  and a threaded hole  342 . 
     The two sprocket wheels  16  are provided with a center through hole  161  by which the sprocket wheels  16  are mounted on both ends of the drive axle  34  in conjunction with two bearings  32 . The two sprocket wheels  16  are actuated by the drive axle  34  to drive the driven chains  17 . The two footrests  11  are respectively fastened with the driven chains  17  such that the footrests  11  are driven to move up and down along the support frames  10 . The footrests  11  is provided with a connection rod  12  and a fastening block  18  which is fastened to the connection rod  12  for fastening the footrest  11  to the driven chain  17 , as shown in FIG.  2 . 
     The support frames  10  are provided with a cover  13 , which is fastened to the support frame  10  by a plurality of fastening screws  15 . The cover  13  is intended to conceal the sprocket wheels  16  and the driven chains  17 , as shown in FIG.  1 . 
     As the motor  20  is started, the transmission gear  33  is actuated by the deceleration gear  211  of the motor spindle  21 . The motion is then imparted to the drive axle  34  from the transmission gear  33 , thereby causing the two sprocket wheels  16  to turn so as to drive the driven chain  17 . As a result, the footrests  11  are caused by the driven chains  17  in motion to move up and down along the support frames  10 . The up-and-down movement of the footrests  11  serves to bring about a training effect on a person&#39;s legs resting on the footrests  11 . The present does not exert a force to activate or operate the exercise device of the present invention. The exercise device of the present invention is thus adapted to rehabilitate a person&#39;s legs under treatment.