Dual-feed single-cam compound bow

Abstract

A cam is eccentrically journaled at one end of a compound archery bow and a pulley is journaled at the other end of the bow. A cable passes around the pulley to form a bowstring section and a second cable section, both sections forming a dual feed single cam compound bow. The amount of feed out to both ends of the bowstring is approximately the same. One embodiment of the cam provides a large radius cam groove and a smaller radius cam groove which are designed to synchronize the rate of cable feed out at both ends of the bowstring section during the drawing operation. An anchor cable is provided to tie the two limbs of the bow together during the flexing of the bow.

1 . A compound archery bow comprising a least a first bow limb attached to a handle and at least a second bow limb attached to the opposing end of said handle, said bow limbs each having a single axle pin therein and wherein an eccentrically rotatably mounted cam is mounted on the single axle pin on said second bow limb, an anchor cable attached to an axle pin in said first bow limb, a bowstring cable section attached to the cam, a return cable section attached to the cam whereby rotation of the eccentrically rotatably mounted cam by the bowstring section causes the bowstring cable section to be let off and during at least a portion of said cam rotation said return cable section is let off, and whereby the rotation of the cam causes the anchor cable to be taken up by said cam. 
   
   
       2 . The bow of  claim 1 , wherein said anchor cable has a first end anchored to the axle pin on said first bow limb and has a second end received in a groove on said cam. 
   
   
       3 . A compound bow as set forth in  claim 2 , wherein the first end of said anchor cable has two sections, and wherein each such section is anchored to opposing ends of said axle pin. 
   
   
       4 . The bow of  claim 1 , wherein said bowstring cable section and said return cable section have end portions received in groove paths extending around the axle pin of said cam. 
   
   
       5 . The bow of  claim 4 , wherein said bowstring cable section and said return cable section are anchored to anchor pins fixed to said cam. 
   
   
       6 . A compound archery bow comprising at least first and second bow limbs attached to opposing ends of a handle, an eccentrically rotatably mounted cam mounted on one of said bow limbs with an axle pin extending through said cam, an anchor cable attached between an axle pin on the one of said bow limbs opposite said cam and said eccentrically mounted cam, a bowstring cable and a return cable attached to said eccentrically mounted cam, whereby rotation of the eccentrically rotatably mounted cam by the bowstring cable causes the bowstring cable to be let off along a first groove path of the eccentrically rotatably mounted cam, whereby during at least a portion of said cam rotation the return cable is let off along a second groove path of the eccentrically rotatably mounted cam, and whereby the rotation of the eccentrically rotatably mounted cam by the bowstring cable causes the anchor cable to be taken up. 
   
   
       7 . The bow of  claim 6 , wherein said second groove path has a different length than said first groove path. 
   
   
       8 . The bow of  claim 7 , wherein said first groove path has a larger periphery than the periphery of said second groove path. 
   
   
       9 . The compound bow of  claim 8 , wherein said first groove path has an eccentrically oriented periphery. 
   
   
       10 . The bow of  claim 6 , wherein said anchor cable has a first end anchored to the axle pin on the one of said bow limbs opposite said cam and has a second end received in a third groove path on said cam. 
   
   
       11 . A compound bow as set forth in  claim 10 , wherein the first end of said anchor cable has two sections, and wherein each such section is anchored to the axle pin at opposing ends of said axle pin. 
   
   
       12 . A compound archery bow comprising at least first and second bow limb portions attached to opposing ends of a handle, an eccentrically rotatably mounted cam defining a bowstring cam and a return cable cam mounted on one of said bow limb portions with an axle extending through said bowstring cam and said return cable cam, an anchor cable attached to an axle in the one of said first and second bow limb portions opposite said cam, a bowstring cable attached to said bowstring cam, a return cable attached to said return cable cam whereby rotation of the eccentrically rotatably mounted cam by the bowstring cable causes the bowstring cable to be let off and during at least a portion of said cam rotation to cause the return cable to be let off, and whereby the rotation of the cam causes the anchor cable to be taken up by said cam. 
   
   
       13 . The bow of  claim 12 , wherein said anchor cable has a first end anchored to the axle and has a second end received in a cam groove on said cam. 
   
   
       14 . A compound bow as set forth in  claim 13 , wherein the first end of said anchor cable has two sections, and wherein each such section is anchored to the axle on said second bow limb adjacent opposing ends of said axle. 
   
   
       15 . The bow of  claim 14  wherein said bowstring cable and said return cable are received in first and second groove paths extending around the axle pin of said cam. 
   
   
       16 . The bow of  claim 15 , wherein said second groove path has a different length than said first groove path. 
   
   
       17 . The bow of  claim 16 , wherein said first groove path receives said bowstring cable and has a larger periphery than the periphery of the second groove path. 
   
   
       18 . The compound bow of  claim 17 , wherein said first groove path has an eccentric periphery.