Compound Bow with Offset Synchronizer

Abstract

In some embodiments, an archery bow comprises a frame supporting a first limb and a second limb. A first rotatable member is supported by the first limb and arranged to rotate about a first rotation axis. The first rotatable member comprises a cam track. A second rotatable member is supported by the second limb and arranged to rotate about a second rotation axis. The second rotatable member comprises a synchronizer track. A bowstring extends between the first rotatable member and the second rotatable member. A power cable is arranged to be taken up on the cam track and fed out from the synchronizer track as the bow is drawn. The synchronizer track is circular and a centerpoint of the synchronizer is offset from the second rotation axis.

1 . A rotatable member for use in a compound bow comprising:
 a body arranged to rotate about an axis, said rotatable member comprising a bowstring track, a power cable track and a synchronizer track, said bowstring track defining a circular arc, said power cable track defining a circular arc, said synchronizer track defining a circular arc;   wherein each of said bowstring track, said power cable track and said synchronizer track define a centerpoint that is offset from said axis.   
     
     
         2 . The rotatable member of  claim 1 , wherein each of said centerpoints is aligned in a plane that includes said axis. 
     
     
         3 . The rotatable member of  claim 1 , wherein said centerpoint of said bowstring track is offset from said centerpoint of said power cable track. 
     
     
         4 . The rotatable member of  claim 1 , wherein said centerpoint of said bowstring track is aligned upon said centerpoint of said power cable track. 
     
     
         5 . The rotatable member of  claim 1 , wherein a radius of said power cable track is smaller than a radius of said bowstring track. 
     
     
         6 . The rotatable member of  claim 1 , wherein said bowstring track comprises a radius that is similar to a radius of said power cable track. 
     
     
         7 . The rotatable member of  claim 6 , wherein said centerpoint of said bowstring track aligned upon said centerpoint of said power cable track. 
     
     
         8 . The rotatable member of  claim 7 , wherein each of said centerpoints is aligned in a plane that includes said axis. 
     
     
         9 . An archery bow comprising:
 a frame supporting a first limb and a second limb;   a first rotatable member supported by the first limb and arranged to rotate about a first rotation axis, the first rotatable member comprising a cam track;   a second rotatable member supported by the second limb and arranged to rotate about a second rotation axis, the second rotatable member comprising a synchronizer track;   a bowstring extending between the first rotatable member and the second rotatable member;   a power cable arranged to be taken up on the cam track and fed out from the synchronizer track as the bow is drawn;   wherein the synchronizer track is circular and a centerpoint of the synchronizer is offset from the second rotation axis.   
     
     
         10 . The archery bow of  claim 9 , wherein the power cable extends around the axis of rotation, crosses itself and attaches to the second rotatable member. 
     
     
         11 . The archery bow of  claim 10 , the synchronizer track oriented in a plane, the second rotatable member comprising a cable terminal that is offset from the plane, the power cable attached to the cable terminal. 
     
     
         12 . The archery bow of  claim 9 , wherein the cam track is circular and a centerpoint of the cam track is offset from the first rotation axis. 
     
     
         13 . The archery bow of  claim 12 , the first rotatable member comprising a bowstring track, the bowstring track being circular, a centerpoint of the bowstring track offset from the first rotation axis. 
     
     
         14 . The archery bow of  claim 13 , wherein a radius of the bowstring track is equal to a radius of the power cable track. 
     
     
         15 . The archery bow of  claim 9 , the power cable applying a force to the second rotatable member, the force having a moment arm distance, wherein the moment arm distance is greater in a fully drawn condition than in a brace condition. 
     
     
         16 . The archery bow of  claim 15 , wherein the moment arm distance reaches a maximum in the fully drawn condition. 
     
     
         17 . The archery bow of  claim 9 , the first rotatable member comprising a synchronizer track having a circular shape and a centerpoint offset from the first rotation axis.