Unit of a flection exerciser

Abstract

A unit of a flection exerciser is made of resilient and durable plastic material in one-piece. Two ends of the flection exerciser are two enlarged grip portions and has an extension portion connected the two ends. The two grip portions have a pin joint and a box joint respectively, wherein each joint is a cylindrical body with two annular flanges at two ends and a slot longitudinally in the cylindrical body. The pin joint has an insertion formed at a distal surface thereon and the box joint has a corresponding insertion hole defined at a distal end thereon. By having the pin joint and the box joint, the unit conveniently connects with other same units to elongate or loop to perform the flection exerciser in various types.

1 . A unit of a flection exerciser comprising: two enlarged grip portions and an extension portion connected between the two enlarged grip portions to compose an one-piece body made of resilient and durable plastic material; a pin joint embedded in one enlarged grip portion; and a box joint embedded in the other enlarged grip portion and corresponding to the pin joint.  
   
   
       2 . The unit of a flection exerciser as claimed in  claim 1 , wherein the pin joint comprises: 
 a cylindrical body with two ends;    an insertion axially formed on the cylindrical body of the pin joint and having a locking stub formed at a distal end of the insertion;    a slot longitudinally defined in the cylindrical body of the pin joint; and    two annular flanges respectively formed at the two ends of the cylindrical body of the pin joint;    wherein, the box joint comprises:    a cylindrical body with two ends;    an insertion hole axially defined in the cylindrical body of the box joint;    an L-shaped groove defined on an inner wall of the insertion hole and corresponding to the locking stub on the pin joint;    a slot longitudinally defined in the cylindrical body of the box joint; and    two annular flanges respectively formed at the two ends of the box joint.    
   
   
       3 . The unit of a flection exerciser as claimed in  claim 2 , wherein an insertion hole of the box joint has a depth larger than a length of the insertion on the pin joint.  
   
   
       4 . The unit of a flection exerciser as claimed in  claim 2 , wherein the L-shaped groove has a distal bent section slightly extending to an opening of the insertion hole.