Resistance device for fitness and bodybuilding equipment

Abstract

A resistance device for use with an exercise machine includes an arbor member structured to be rotatably coupled with respect to the exercise machine. The arbor member having a first end and an opposite second end. The resistance device further having a first hub coupled to the arbor member, the hub having a contact portion of variable radius; a cord member having a first end and an opposite second end, the first end being coupled to the arbor member at or about the first hub, the cord member wound about the first hub at the contact portion; an elastic element having a first end and an opposite second end, the first end being coupled to the second end of the cord member and the second end being structured to be coupled to a point fixed relative to the exercise machine; a second hub coupled to the arbor member, the second hub being structured to be coupled to a user actuatable member; and an adjustment mechanism coupled to the first hub, the adjustment mechanism being adapted selectively to vary the radius of the contact portion of the first hub.

1 . A resistance device for use with an exercise machine, the resistance device comprising:
 an arbor member structured to be rotatably coupled with respect to the exercise machine, the arbor member having a first end and an opposite second end;   a first hub coupled to the arbor member, the first hub having a contact portion of variable radius;   a cord member having a first end and an opposite second end, the first end being coupled to the arbor member at or about the first hub, the cord member wound about the first hub at the contact portion;   an elastic element having a first end and an opposite second end, the first end being coupled to the second end of the cord member and the second end being structured to be coupled to a point fixed relative to the exercise machine;   a second hub coupled to the arbor member, the second hub being structured to be coupled to a user actuatable member; and   an adjustment mechanism coupled to the first hub, the adjustment mechanism being adapted selectively to vary the radius of the contact portion of the first hub.   
     
     
         2 . The resistance device of  claim 1  wherein:
 the arbor member comprises a number of guide members coupled thereto; and 
 the first hub comprises a conical shaped member of varying radius moveable with respect to the number of guide members by the adjustment mechanism. 
 
     
     
         3 . The resistance device of  claim 1  wherein the adjustment mechanism comprises a crank member threadedly coupled to the first hub. 
     
     
         4 . The resistance device of  claim 1  wherein the elastic element comprises a spring member. 
     
     
         5 . The resistance device of  claim 1  wherein the elastic element comprises a beam member. 
     
     
         6 . The resistance device of  claim 1  wherein the elastic element comprises a torsionally deflected member. 
     
     
         7 . An exercise machine comprising:
 a frame;   a user actuatable member moveable relative to the frame; and   a resistance device comprising:
 an arbor member structured to be rotatably coupled to the exercise machine, the arbor member having a first end and an opposite second end; 
 a first hub coupled to the arbor member, the first hub having a contact portion of variable radius; 
 a cord member having a first end and an opposite second end, the first end being coupled to the arbor member at or about the first hub, the cord member wound about the first hub at the contact portion; 
 an elastic element having a first end and an opposite second end, the first end being coupled to the second end of the cord member and the second end being be coupled to a point fixed relative to the frame; 
 a second hub coupled to the arbor member, the second hub being coupled to a user actuatable member via a flexible member; and 
 an adjustment mechanism coupled to the first hub, the adjustment mechanism being adapted to selectively vary the radius of the contact portion of the first hub. 
   
     
     
         8 . The exercise machine of  claim 7  wherein:
 the arbor member comprises a number of guide members coupled thereto; and 
 the first hub comprises a conical shaped member of varying radius moveable with respect to the number of guide members by the adjustment mechanism. 
 
     
     
         9 . The exercise machine of  claim 7  wherein the adjustment mechanism comprises a crank member threadedly coupled to the first hub. 
     
     
         10 . The exercise machine of  claim 7  wherein the elastic element comprises one of a spring member, beam member, or torsionally loaded member.