Patent ID: 9574841
Date: 2017-02-21
CPC Classifications: F41B

Claim:
1. A crossbow for shooting an arrow, the crossbow comprising a receiver and a bow frame, the bow frame extending between a first frame end and a second frame end, the crossbow being configured to support and shoot an associated arrow generally along a firing axis that extends along the receiver, the bow frame and the receiver being generally rigid, the bow frame having a first firing system joined relative to the first frame end and a second firing system joined relative to the second frame end; the first firing system including a first spring assembly fixable relative to the first frame end with a first spring passage shaped to receive a first compression spring assembly, the first compression spring assembly including a first compression spring extending along a first spring axis between a first spring first end and a first spring second end, the first spring second end having a first spring cap and the first spring assembly including a first cap opening wherein the first spring cap is exposed, the first firing system further including a first crank rotatably attached relative to the first spring assembly about a first crank axis and having a first spring portion and a first string portion with a first pivot region joined to the first spring and string portions, the first spring portion being shaped to engage the first spring cap, the string portion having a first mount to rotatably support a first rotatable bow string support about a first support axis wherein the first support includes a first outwardly facing guide groove for a bow string that is guided therein about the first support axis; the second firing system including a second spring assembly fixable relative to the second frame end and having a second spring passage shaped to receive a second compression spring assembly, the second compression spring assembly including a second compression spring extending along a second spring axis between a second spring first end and a second spring second end, the second spring second end having a second spring cap, the second spring assembly including a second opening wherein the second spring cap is exposed, the second firing system further including a second crank rotatably attached relative to the second spring assembly about a second crank axis and having a second spring portion and a second string portion with a second pivot region joined to the second spring and string portions, the second spring portion being shaped to engage the second spring cap, the second string portion having a second mount to rotatably support a second rotatable bow string support about a second support axis wherein the second support includes a second outwardly facing guide groove for the bow string that is guided therein about the second support axis; the first support axis being parallel to the second support axis; the bow string extending between the first and second rotatable bow string supports wherein when the bow string is pulled toward a full drawn condition the first and second rotatable bow string supports rotate thereby rotating the first and second cranks about the first and second crank axes and compressing the first and second compression springs, the first and second compression springs providing an amount of stored energy to propel the associated arrow when the bow string is released.