Compound bow

Abstract

Provided is a compound bow including: first and second cam cables between upper and lower pulley assemblies, wherein the lower cable of the first cam cable comprises: a one-side cable portion and the other-side cable portion on both sides of the pulley, in which either end of the lower cable is coupled to a fixing projection formed at either side of the pulley, and the one-side cable portion and the other-side cable portion of the lower cable are supported by a spacing member so as to maintain a constant interval, to thus make the one-side cable portion and the other-side cable portion of the lower cable wound on the respective cams formed at both sides of the pulley, while maintaining the one-side cable portion and the other-side cable portion of the lower cable to have the constant interval by the spacing member, as a bowstring is pulled.

We claim: 
     
         1 . A compound bow comprising:
 a bow main body including a handle at a central portion of which a grip portion is formed and a pair of limbs that are respectively coupled to both ends of the handle;   upper and lower pulley assemblies each including a pulley that is rotatably coupled to a rotating shaft formed on the rear end of each limb, and a cam that is coupled to the pulley and is rotated with the pulley;   a bowstring whose either end is wound on and coupled to the pulley of each of the upper and lower pulley assemblies; and   first and second cam cables that are wound around the cam of each of the upper and lower pulley assemblies as the bowstring is pulled, in which one end of each of the first and second cam cables is coupled to one of the upper and lower pulley assemblies, and the other end thereof is coupled to the other of the upper and lower pulley assemblies or the rotating shaft of the other of the upper and lower pulley assemblies,   wherein the respective cams are provided on one side and the other side of the pulley in the lower pulley assembly,   the first cam cable comprises: a central cable; an upper cable that is connected to the upper side of the central cable; and a lower cable that is connected to the lower side of the central cable,   the upper cable comprises: a one-side cable portion and the other-side cable portion that are positioned on both sides of the pulley of the upper pulley assembly, in which either end of the upper cable is coupled to the rotating shaft to which the upper pulley assembly is coupled at either side of the pulley of the upper pulley assembly,   the lower cable comprises: a one-side cable portion and the other-side cable portion that are positioned on both sides of the pulley of the lower pulley assembly, in which either end of the lower cable is coupled to a fixing projection that is formed at either side of the pulley of the lower pulley assembly, and   the one-side cable portion and the other-side cable portion of the lower cable are supported by a spacing member so as to maintain a constant interval, to thus make the one-side cable portion and the other-side cable portion of the lower cable wound on the respective cams formed at both sides of the pulley of the lower pulley assembly, while maintaining the one-side cable portion and the other-side cable portion of the lower cable to have the constant interval by the spacing member, as the bowstring is pulled, to thereby minimize twisting of the bow limbs and improve accuracy of an arrow.   
     
     
         2 . The compound bow of  claim 1 , wherein the spacing member is formed in a ring shape. 
     
     
         3 . The compound bow of  claim 1 , wherein a lower loop is formed at a lower end of the central cable, and a central portion of the lower cable and the lower loop of the central cable are supported on an outer circumferential surface of the spacing member so that the central cable and the lower cable are interconnected. 
     
     
         4 . The compound bow of  claim 3 , wherein the lower loop of the central cable is supported on a lower portion of the outer circumferential surface of the spacing member, and a central portion of the lower cable is supported on an upper portion of the outer circumferential surface of the spacing member. 
     
     
         5 . The compound bow of  claim 3 , wherein the lower loop of the center cable is made of two loops, and the central portion of the lower cable is supported on the outer circumferential surface of the spacing member between the two loops. 
     
     
         6 . The compound bow of  claim 1 , wherein a throughhole is formed at the center of the spacing member, and a damper member is coupled within the throughhole to thereby damp vibrations of the first cam cable. 
     
     
         7 . The compound bow of  claim 6 , wherein the damper member is configured as having a cylindrical central portion that is fitted in the throughhole of the spacing member, and both end portions of a larger diameter than the center portion in which both the end portions are located in both side surfaces of the spacing member. 
     
     
         8 . The compound bow of  claim 1 , wherein the one-side cable portion and the other-side cable portion that are positioned on both sides of the pulley of the upper pulley assembly in the upper cable are supported by another spacing member so as to maintain a constant interval. 
     
     
         9 . The compound bow of  claim 8 , wherein the other spacing member is formed in a ring shape. 
     
     
         10 . The compound bow of  claim 8 , wherein an upper loop is formed at an upper end of the central cable, and a central portion of the upper cable and the upper loop of the central cable are supported on an outer circumferential surface of the other spacing member so that the central cable and the upper cable are interconnected. 
     
     
         11 . The compound bow of  claim 1 , wherein the respective cams of each of the pulley assemblies comprise: a cam cable support portion supporting the cam cable; a cam module that is movably coupled in an arc trajectory on the pulley to which the cams are coupled; and a fixing unit that fixes the cam module at a desired position on the pulley in order to adjust a draw length of a let-off state, in which the cam cable is supported on the cam cable support portion and then is wound on the outer circumferential surface of the cam module, when the bowstring is pulled,
 the second cam cable is coupled to the fixing projection that is formed in the cam module and moves along as the cam module moves, is wound on a cam cable winding portion that is penetrated by the rotating shaft via a compensation projection, and then extends toward the other side pulley assembly, and   a front portion of the cam module is in contact with the second cam cable and thus the second cam cable is bent when the cam module is moved in which one end of the second cam cable is coupled to the fixing projection of the cam module in order to adjust the draw length of the let-off state, to thus release the second cam cable from the cam cable winding portion via the compensating projection from the fixing projection to which the second cam cable is coupled, to thereby maintain constant tension of the cam cable and keep the power of the bow.   
     
     
         12 . The compound bow of  claim 11 , wherein the cam module is rotatably coupled at a predetermined angle from the cam cable support portion around a pivoting point at a position spaced apart from the rotating shaft of the pulley. 
     
     
         13 . The compound bow of  claim 12 , wherein an arc-shaped position adjusting hole is formed on the pulley on which the cam module is coupled, and the cam module is movably coupled to the pulley along the position adjusting hole. 
     
     
         14 . A compound bow comprising:
 a bow main body including a handle at a central portion of which a grip portion is formed and a pair of limbs that are respectively coupled to both ends of the handle;   upper and lower pulley assemblies each including a pulley that is rotatably coupled to a rotating shaft formed on the rear end of each limb, and a cam that is coupled to the pulley and is rotated with the pulley;   a bowstring whose either end is wound on and coupled to the pulley of each of the upper and lower pulley assemblies; and   first and second cam cables that are wound around the cam of each of the upper and lower pulley assemblies as the bowstring is pulled, in which one end of each of the first and second cam cables is coupled to one of the upper and lower pulley assemblies, and the other end thereof is coupled to the other of the upper and lower pulley assemblies or the rotating shaft of the other of the upper and lower pulley assemblies,   wherein the respective cams are provided on one side and the other side of each of the pulleys around the respective pulleys in the upper and lower pulley assemblies,   each of the first and second cam cables comprises: a first cable that is coupled with one pulley assembly; and a second cable that is connected to the first cable and coupled with the other pulley assembly,   the first cable comprises: a one-side cable portion and the other-side cable portion that are positioned on both sides of the pulley, in which either end of the first cable is coupled to a fixing projection that is formed at either side of the pulley of the pulley assembly to which the first cable is coupled, and   the one-side cable portion and the other-side cable portion of the first cable are supported by a spacing member so as to maintain a constant interval, to thus make the one-side cable portion and the other-side cable portion of the first cable wound on the respective cams formed at both sides of the pulley of the pulley assembly to which the first cable is coupled, while maintaining the one-side cable portion and the other-side cable portion of the first cable to have the constant interval by the spacing member, as the bowstring is pulled, to thereby minimize twisting of the bow limbs and improve accuracy of an arrow.   
     
     
         15 . The compound bow of  claim 14 , wherein the spacing member is formed in a ring shape. 
     
     
         16 . The compound bow of  claim 14 , wherein a central portion of the first cable and a loop that is formed at one end of the second cable are supported on the outer circumferential surface of the spacing member and thus the first cable and the second cable are interconnected. 
     
     
         17 . The compound bow of  claim 14 , wherein a throughhole is formed at the center of the spacing member, and a damper member is coupled within the throughhole to thereby damp vibrations of the cam cables. 
     
     
         18 . The compound bow of  claim 1 , wherein the respective cams of each of the pulley assemblies comprise: a cam cable support portion supporting the cam cable; a cam module that is movably coupled in an arc trajectory on the pulley to which the cams are coupled; and a fixing unit that fixes the cam module at a desired position on the pulley in order to adjust a pulling length of a let-off state, in which the cam cable is supported on the cam cable support portion and then is wound on the outer circumferential surface of the cam module, when the bowstring is pulled,
 the second cable is coupled to the fixing projection that is formed in the cam module and moves along as the cam module moves, is wound on a cam cable winding portion that is formed around the rotating shaft via a compensation projection, and then extends toward the other side pulley assembly, and   a front portion of the cam module is in contact with the second cable and thus the second cable is bent when the cam module is moved in which one end of the second cable is coupled to the fixing projection of the cam module in order to adjust the draw length of the let-off state, to thus release the second cable from the cam cable winding portion via the compensating projection from the fixing projection to which the second cable is coupled, to thereby maintain constant tension of the cam cable and keep the power of the bow.