Arrowhead with pivotable blades

摘要

An arrowhead with pivotal blades has a body with a mounting location adjacent a first end of the body. An elongated blade has a first end of the blade pivotably mounted to the mounting location of the body about an axis of rotation such that the blade is pivotably movable between first and second positions. The blade lies substantially parallel to the longitudinal axis of the body when in the first position with the second end of the blade adjacent the second end of the body, and the second end of the blade extends outward and closer to the first end of the body when the blade is in the second position. A bearing surface is formed at the second end of the blade so as to be contacted by a target surface to pivot the blade from the first position to the second position when the bearing surface strikes a target. The blade has a cam portion formed thereon adjacent the axis of rotation. A spring adjacent the axis of rotation of the blade is oriented to exert a force against the cam portion of the blade in the approximate direction of the axis of rotation. The cam portion of the blade is configured such that a biasing force tending to pivot the blade into the first position is exerted during a first minor portion of rotation of the blade between the first position and the second position.