Expandable arrowhead or broadhead

Abstract

An expandable arrowhead having a blade-carrying body with a slot that houses at least one pivotally mounted blade. Each blade can be pivotally mounted about a shaft. In some embodiments, the shaft is fixed with respect to the body. In some embodiments of this invention, a spring element positively holds one or more blades in a closed position or a retracted position, particularly during extreme forces encountered when launching an arrow from an archery bow, such as a compound archery bow. The spring element of this invention can be used to improve blade opening capabilities of conventional blade-opening arrowheads or broadheads.

1 . A blade-opening broadhead comprising:
 a body having an opening, at least one blade pivotally mounted within the opening and movable between a retracted position and an expanded position, and a spring element mounted with respect to and contacting the body and each blade.   
     
     
         2 . The blade-opening broadhead according to  claim 1 , wherein the spring element frictionally contacts the body and/or the at least one blade. 
     
     
         3 . The blade-opening broadhead according to  claim 1 , wherein the spring element is a wave washer. 
     
     
         4 . The blade-opening broadhead according to  claim 1 , wherein the spring element has a detent potion and/or a raised portion contacting the body and/or the at least one blade. 
     
     
         5 . The blade-opening broadhead according to  claim 1 , wherein the spring element has a retaining force applied to the at least one blade. 
     
     
         6 . The blade-opening broadhead according to  claim 1 , wherein a retaining force holds the at least one blade in the retracted position during a launch and/or a flight of an attached arrow shaft. 
     
     
         7 . The blade-opening broadhead according to  claim 1 , wherein a retaining force allows the at least one blade to move from the retracted position to the expanded position upon impact with a target. 
     
     
         8 . The blade-opening broadhead according to  claim 1 , wherein in the expanded position the at least one blade has a larger cutting diameter than when the at least one blade is in the retracted position. 
     
     
         9 . The blade-opening broadhead according to  claim 1 , wherein an opening force applied to an impact portion of the at least one blade moves the at least one blade from the retracted position to the expanded position. 
     
     
         10 . An improvement to a blade-opening broadhead having a blade movable with respect to a body, the improvement comprising:
 a first blade and a second blade each mounted within an opening of the body to pivot with respect to each other and with respect to the body, the first blade and the second blade moving between a retracted position and an expanded position, and a spring element contacting the body, the first blade and/or the second blade to apply a retaining force holding the first blade and the second blade in the retracted position during a launch and/or a flight of an attached arrow shaft and the retaining force allowing the first blade and the second blade to move from the retracted position to the expanded position upon impact with a target.   
     
     
         11 . The blade-opening broadhead according to  claim 10 , wherein the spring element frictionally contacts the body, the first blade and/or the second blade. 
     
     
         12 . The blade-opening broadhead according to  claim 10 , wherein an opening force applied to an impact portion of the first blade and/or the second blade moves the first blade and the second blade from the retracted position to the expanded position. 
     
     
         13 . The blade-opening broadhead according to  claim 10 , wherein in the expanded position the first blade and the second blade form a larger cutting diameter than with the first blade and the second blade in the retracted position. 
     
     
         14 . The blade-opening broadhead according to  claim 10 , wherein the spring element is detachably secured to the body, the first blade and/or the second blade. 
     
     
         15 . A method for pivoting a first blade and a second blade of a broadhead, the method comprising:
 Movably mounting a first blade within an opening of a body to pivot with respect to the body;   Movably mounting a second blade within the opening of the body to pivot with respect to the body;   moving the first blade and the second blade between a retracted position and an expanded position;   contacting a spring element with the body, the first blade and/or the second blade;   applying a retaining force to the first blade and the second blade in the retracted position and the.   
     
     
         16 . The method according to  claim 15 , wherein the retaining force is applied during a launch and/or a flight of an attached arrow shaft. 
     
     
         17 . The method according to  claim 15 , wherein the retaining force allows the first blade and the second blade to move from the retracted position to the expanded position upon impact with a target. 
     
     
         18 . The method according to  claim 15 , wherein an impact force is applied to the first blade and/or the second blade to move the first blade and the second blade into the expanded position. 
     
     
         19 . The method according to  claim 18 , wherein the impact force is varied to allow the first blade and the second blade from the retracted position to the expanded position. 
     
     
         20 . The method according to  claim 15 , wherein the retaining force is sized to overcome generated launch forces and hold the first blade and the second blade in the retracted position during a launch and/or a flight of an attached arrow shaft and the retaining force is sized to allow the first blade and the second blade to move from the retracted position into the expanded position when the first blade and/or the second blade contacts a target.