Patent Publication Number: US-6659922-B1

Title: Resistance adjustment mechanism for easy pull exerciser

Description:
FIELD OF THE INVENTION 
     The present invention is related to the resistance adjustment mechanism for an easy pull exerciser. Especially it means a simple control mechanism that provides variable frictional forces. 
     BACKGROUND OF THE INVENTION 
     Usually, a pull exerciser uses spiral spring as a return device for rewinding the pull. When the pull string is pulled, frictional resistance takes place between a friction device and the pull string, so a load applies to the user in exercise. But traditional pull exerciser does not have the function to adjust the frictional force for the pull string and the degree of tightness for the spiral spring. Practically, it does not meet the need for different users in exercise under different condition. 
     SUMMARY OF THE INVENTION 
     The main objective for the present invention is to provide a resistance adjustment mechanism for an easy pull exerciser, which uses a flexible moving gear axis to adjust the degree of tightness of a spiral spring when it rotates under inward pressure. The mechanism further controls the resilient force for the pull string and allows the gear axis to position to the inner ring gear when it is back to normal state. Thus, the gear axis can be adjusted easily and positioned securely. 
     Another objective for the present invention is to provide a mechanism to adjust the frictional force for the pull string, so the user can adjust the tightness for the pull string according to the practical condition and be satisfied with the exerciser. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a three-dimensional view for the present invention. 
     FIG. 2 is a three-dimensional de-compositional view for the present invention. 
     FIG. 3 is a two-dimensional illustration for the inner structure for the present invention. 
     FIG. 4 is a two-dimensional illustration for the inner structure of another embodiment for the present invention. 
     FIG. 5 is a cross-sectional view obtained through the direction of  5 — 5  cross-sectional line and arrow shown in FIG.  1 . 
     FIG. 6 is an illustration for the structure and the gear axis adjustment status shown in FIG.  5 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     An embodiment is described in details with the following figures. 
     Please refer to FIGS. 1 to  3 . The pull exerciser for the present invention comprises an outer shell  1 , an adjustment device  2 , a winding wheel  3  and a gear axis  4 . The outer shell  1  contains a pair of semi-spherical parts: the first shell  11  and the second shell  12 . On one sides of the first shell  11  and the second shell  12 , there are handles  111 ,  121  available for hand grasping. Near the center, there are axis holders  112 ,  122 . On the other sides of the first shell  11  and the second shell  12 , there are cavities  114 ,  124  available to firmly hold an adapter  13  and allow the pull string  32  for the winding wheel  3  to pass through. The winding wheel  3  is warped around by the pull string  32 . One end of the pull string  32  is fixed to the winding wheel  3 . The other end of the pull string  32  is fixed to a pull handle  33 . The pull string  32  can pass through or be rewinded in the adapter  13 . 
     Please refer to FIGS. 3 to  5 . The said winding wheel  3  forms a side concavity  31  on one side for placing the spiral spring  45 . The winding wheel  3  is located at the outer shell  1  by passing the gear axis  4  through. The outer bending terminal  451  for the spiral spring  45  is fixed to the side cavity  31  for the winding wheel  3 . The inner bending terminal  451  for the spiral spring  45  is fixed to the positioning groove  42  for the gear axis  4 . By pulling the pull string, the spiral spring  45  is deformed and twisted. When no pulling force is applied to the pull handle  33  of the pull string  32 , the winding spring  45  is back to normal state and the winding wheel  3  is wrapped around by the pull string  32 . 
     Please refer to FIG.  3 . On the back of the said first shell  11  near the adapter  13 , there is an adjustment device  2  that contains a rotating knob  21 , retainer  22  and one-way clutch bearing  23 . The retainer  22  is clamped and fixed to the first shell  11 . The outside of the retainer  22  is available for the thread stud  211  of the rotating knob  21  to pass through. The thread stud  211  connects to the one-way clutch bearing  23 . Through the rotating knob  21 , the distance for the one-way clutch bearing  23  to move inward or outward can be adjusted. A curved plate  113  is located in front of the one-way clutch bearing  23  at a corresponding position to the adjustment device  2 . The curved plate  113  allows the pull string  32  of the winding wheel  3  to move smoothly along the curved surface. 
     Please refer to FIG. 5 again. Inside the axis holder  122  for the second shell  12  of the outer shell  1 , there is a inner ring gear  123  for holding the gear axis  4 . There is a multilateral hole  43  at the outer end of the gear axis  4 . On the gear axis  4 , there is a circle of teeth  41 . On the back, there is an extended hollow axis tube  44 . There is an elastic device  441  inside the axis tube  44 . Under normal condition, the teeth  41  for the gear axis  4  match the inner ring gear  123  for the second shell  12  due to the action of the elastic device  441 . Because of the flexible arrangement of the gear axis  4 , the gear axis can be pressed inward and rotate to adjust the degree of tightness of the spiral spring  45 . Further, the resilient force for the pull string  32  can be controlled. Besides, when the gear axis  4  is back to normal state, the teeth  41  can be positioned to the inner ring gear  123 . Thus, the mechanism provides easy adjustment and secured position for the gear axis  4 . 
     Furthermore, the curved plate  113  for the first shell  11 ′ for the pull string  32  to move smoothly can be replaced by a one-way clutch bearing  112 ′ as shown in FIG.  6 . For the first shell  11 ′, near one end of the pull string  32  for the winding wheel  3 , there is an adjustment device  2 , which contains a rotating knob  21 , a retainer  22  and a one-way clutch bearing  23 . The retainer  22  is clamped and fixed to the first shell  11 ′. The outside of the retainer  22  is available for the thread stud  211  of the rotating-knob  21  to pass through. The thread stud  211  connects to the one-way clutch bearing  23 . A curved plate  112 ′ is located in front of the one-way clutch bearing  23  for the outer shell  1 ′ at a corresponding position to the adjustment device  2 . The curved plate  112 ′ allows the pull string  32  to move along its surface. Thus, the two one-way clutch bearings can limit the pulling action for the pull string  32  at the same time.