Archery Bow Modular Cam System
A modular cam system for an archery bow or crossbow includes swappable cams that change the maximum draw weight of the archery bow or crossbow. Moreover, the modular cams can be affixed to a rotatable member in a number of orientations to set the desired draw length without changing the limbs, tightening or loosening limb bolts, or disassembling the bow. Further, the maximum draw weight of the bow remains substantially similar throughout a large portion of the draw length adjustment for a specified cam module.
1 . An archery bow comprising:
a riser and opposed limbs, each limb supporting a rotatable member;
at least one rotatable member comprising a body and a cam module, said body defining a bowstring payout track, said cam module defining a power cable take-up track, said cam module adjustable with respect to said body between first and second orientations;
wherein a draw length of said bow in said first orientation is different from a draw length of said bow in said second orientation, a maximum draw weight of said bow in said first orientation is substantially similar to a maximum draw weight of said bow in said second orientation, and the bow has at least 45% let-off in both the first and second orientations.
2 . The archery bow of claim 1 , wherein said cam module is rotated at least 30 degrees with respect to said body between said first and second orientations.
3 . The archery bow of claim 1 , wherein said cam module is rotated at least 50 degrees with respect to said body between said first and second orientations.
4 . The archery bow of claim 1 , wherein said cam module comprises a first cam module having a first shape, said bow further comprising a second cam module that is shaped differently from said first cam module, said first cam module replaceable with said second cam module, wherein a maximum draw weight of said bow using said second cam module is greater than a maximum draw weight of said bow using said first cam module.
5 . The archery bow of claim 4 , wherein said second cam module is adjustable with respect to said body between first and second orientations, wherein a draw length of said bow using said second cam module in said first orientation is different from a draw length of said bow using said second cam module in said second orientation, a draw weight of said bow using said second cam module in said first orientation being substantially similar to a draw weight of said bow using said second cam module in said second orientation.
6 . An archery bow comprising:
a riser and opposed limbs, each limb supporting a rotatable member;
at least one rotatable member comprising a body and a cam module, said body defining a bowstring payout track, said cam module defining a power cable take-up track, said cam module adjustable with respect to said body between a plurality of orientations including a maximum draw length orientation and a minimum draw length orientation;
wherein a draw length of said bow in said maximum draw length orientation is at least eight inches greater than a draw length of said bow in said minimum draw length orientation, a peak draw weight of said bow changing less than 12% over the range of adjustability between said maximum draw length orientation and said minimum draw length orientation.
7 . The bow of claim 6 , wherein the archery bow has at least 45% let-off in both the maximum and minimum draw length orientations.
8 . The bow of claim 6 , wherein a peak draw weight of said bow changes less than 5% over at least 70% of the range of adjustability between said maximum draw length orientation and said minimum draw length orientation.
9 . The bow of claim 6 , said plurality of orientations including an intermediate draw length orientation, a draw length of said bow in said maximum draw length orientation is at least five inches greater than a draw length of said bow in said intermediate draw length orientation, a peak draw weight of said bow changing less than 3% over the range of adjustability between said maximum draw length orientation and said intermediate draw length orientation.
10 . The archery bow of claim 6 , wherein said cam module comprises a first cam module having a first shape, said bow further comprising a second cam module that is shaped differently from said first cam module, said first cam module replaceable with said second cam module, wherein a peak draw weight of said bow using said second cam module is greater than a peak draw weight of said bow using said first cam module.
11 . The archery bow of claim 10 , wherein said second cam module is adjustable with respect to said body between a plurality of orientations including a maximum draw length orientation and a minimum draw length orientation, wherein a draw length of said bow using said second cam module in said maximum draw length orientation is different from a draw length of said bow using said second cam module in said minimum draw length orientation, a peak draw weight of said bow using said second cam module changing less than 12% over the range of adjustability between said maximum draw length orientation and said minimum draw length orientation.
12 . An archery bow kit comprising:
a riser and opposed limbs, each limb supporting a rotatable member;
at least one rotatable member comprising a body and a first cam module, said body defining a bowstring payout track, said cam module defining a power cable take-up track;
said kit further comprising a second cam module suitable for replacing said first cam module, each of said cam modules comprising a let-off portion and a peak weight portion, the peak weight portion of said second cam module being larger than the peak weight portion of said first cam module;
wherein a peak draw weight of said bow using said first cam module is less than a peak draw weight of said bow using said second cam module and the let-off portions of said first and said second cam modules each produce at least 45% let-off in draw weight.
13 . The bow kit of claim 12 , wherein said first cam module is adjustable with respect to said rotatable member body between first and second orientations, a draw length of said bow with said first cam module in said first orientation is different from a draw length of said bow with said first cam module in said second orientation, a peak draw weight of said bow with said first cam module in said first orientation is substantially similar to a peak draw weight of said bow with said first cam module in said second orientation.
14 . The bow kit of claim 13 , wherein said draw length changes at least six inches between said first orientation and said second orientation.
15 . The bow kit of claim 13 , wherein said second cam module is adjustable with respect to said rotatable member body between first and second orientations, a draw length of said bow with said second cam module in said first orientation is different from a draw length of said bow with said second cam module in said second orientation, a peak draw weight of said bow with said second cam module in said first orientation is substantially similar to a peak draw weight of said bow with said second cam module in said second orientation.
16 . The bow kit of claim 15 , wherein said draw length changes at least six inches between said first orientation and said second orientation.