Mass distribution system for an archery bow

Abstract

A mass based tuning system for an archery bow includes rotatable members or cams of the archery bow and a plurality of weights configured to removably attach to the rotatable members (e.g., cams). Modern compound bows have rotatable members (e.g. cams) that provide energy from bow limbs to the bowstring during release or firing of the bow. The shape of the rotatable members has the greatest effect on the energy delivery profile of the bow (i.e., energy or acceleration over time during release or firing of the bow), and mass distribution about the rotatable member has the second highest effect on the energy delivery profile of the bow. Weights are added to (or removed from) corresponding recesses in or holes through the rotatable member to alter the energy delivery profile of the bow in order to fine tune a bow to a given arrow.

What is claimed is: 
     
         1 . A mass distribution system for an archery bow, comprising:
 a rotatable member configured to mount to a limb of the archery bow at a distal end of the archery bow and engage a string of the archery bow such that an axis of rotation of the rotatable member extends laterally with respect to the archery bow when mounted on the archery bow;   wherein the rotatable member comprises a recess configured to receive at least a portion of a weight therein such that the weight alters a rotational balance of the rotatable member when received in the recess.   
     
     
         2 . The mass distribution system of  claim 1 , wherein the mass distribution system further comprises the weight. 
     
     
         3 . The mass distribution system of  claim 1 , wherein a perimeter of the recess is generally circular. 
     
     
         4 . The mass distribution system of  claim 1 , wherein the rotatable member is configured to threadingly engage the weight. 
     
     
         5 . The mass distribution system of  claim 1 , wherein the recess of the rotatable member has a threaded aperture therein configured to threadingly engage the weight. 
     
     
         6 . The mass distribution system of  claim 1 , wherein:
 the mass distribution system further comprises the weight;   the weight is a weighted disc; and   the weight has a thickness corresponding to a depth of the recess such that an upper surface of the weight is generally coplanar with a lateral side of the rotatable member when the weight is received in the recess of the rotatable member.   
     
     
         7 . The mass distribution system of  claim 1 , wherein:
 the mass distribution system further comprises the weight;   the weight is a weighted disc;   the weighted disc is one of a plurality of weighted discs;   the mass distribution system further comprises the plurality of weighted discs;   weighted discs of the plurality of weighted discs have different weights;   weighted discs of the plurality of weighted discs are removably receivable in the recess to redistribute mass throughout the body of the rotatable member and thereby modulate how the archery bow to which the rotatable member is mounted delivers energy to an arrow shot from the archery bow.   
     
     
         8 . The mass distribution system of  claim 1 , wherein:
 the rotatable member is a first rotatable member;   the mass distribution system further comprises a second rotatable member;   the weight is one weight of a plurality of weights of the mass distribution system; and   at least two weights of the plurality of weights are substantially identical.   
     
     
         9 . The mass distribution system of  claim 1 , wherein:
 the recess is a first recess;   the rotatable member is a non-circular cam and has a second recess configured to receive a weight; and   the second recess is at least one of at a different distance from the axis of rotation or not diametrically opposing the first recess.   
     
     
         10 . A mass distribution system for an archery bow, comprising:
 a plurality of weights configured to removably attach to a rotatable member of the archery bow to redistribute mass throughout the body of the rotatable member and thereby modulate how the archery bow to which the rotatable member is mounted delivers energy to an arrow shot from the archery bow.   
     
     
         11 . An archery bow comprising:
 a mass distribution system comprising:   a rotatable member configured to mount to a limb of the archery bow at a distal end of the archery bow and engage a string of the archery bow such that an axis of rotation of the rotatable member extends laterally with respect to the archery bow when mounted on the archery bow;   wherein the rotatable member comprises a recess configured to receive at least a portion of a weight therein such that the weight alters a rotational balance of the rotatable member when received in the recess.   
     
     
         12 . The archery bow of  claim 11 , wherein the mass distribution system further comprises the weight. 
     
     
         13 . The archery bow of  claim 11 , wherein a perimeter of the recess is generally circular. 
     
     
         14 . The archery bow of  claim 11 , wherein the rotatable member is configured to threadingly engage the weight. 
     
     
         15 . The archery bow of  claim 11 , wherein the recess of the rotatable member has a threaded aperture therein configured to threadingly engage the weight. 
     
     
         16 . The archery bow of  claim 11 , wherein:
 the mass distribution system further comprises the weight;   the weight is a weighted disc; and   the weight has a thickness corresponding to a depth of the recess such that an upper surface of the weight is generally coplanar with a lateral side of the rotatable member when the weight is received in the recess of the rotatable member.   
     
     
         17 . The archery bow of  claim 11 , wherein:
 the mass distribution system further comprises the weight;   the weight is a weighted disc;   the weighted disc is one of a plurality of weighted discs;   the mass distribution system further comprises the plurality of weighted discs;   weighted discs of the plurality of weighted discs have different weights;   weighted discs of the plurality of weighted discs are removably receivable in the recess to redistribute mass throughout the body of the rotatable member and thereby modulate how the archery bow to which the rotatable member is mounted delivers energy to an arrow shot from the archery bow.   
     
     
         18 . The archery bow of  claim 11 , wherein:
 the rotatable member is a first rotatable member;   the mass distribution system further comprises a second rotatable member;   the weight is one weight of a plurality of weights; and   at least two weights of the plurality of weights are substantially identical.   
     
     
         19 . The archery bow of  claim 11 , wherein:
 the recess is a first recess;   the rotatable member is a non-circular cam and has a second recess configured to receive a weight; and   the second recess is at least one of at a different distance from the axis of rotation or not diametrically opposing the first recess.   
     
     
         20 . The archery bow of  claim 11 , wherein:
 the rotatable member is a first rotatable member;   the mass distribution system further comprises a second rotatable member;   the weight is one weight of a plurality of weights of the mass distribution system; and   the archery boy further comprises:
 the string configured to engage and extend between the first rotatable member and the second rotatable member; 
 a first limb configured to support the first rotatable member; 
 a second limb configured to support the second rotatable member; and 
 a riser configured to space the first limb from the second limb.