Patent ID: 6251036
Filing Date: 2001-06-26
Classification: F42B

Abstract:
A carbon fiber arrow shaft comprising a hollow tube having a length between 500-900 mm, an inner diameter between 2-10 mm, and a tube wall thickness between 0.3-2 mm, a reinforced carbon fiber, and a resinoid binder, the reinforced carbon fiber binder forming a resin-impregnated carbon fiber, the carbon fiber arrow shaft being formed by directly and continuously winding said resin-impregnated carbon fiber around the hollow tube, said carbon fiber arrow shaft having a head section (L1), a middle section (L2) and a tail section (L3), a winding angle of the carbon fiber at the head section (L1) being changed from a larger winding angle to a smaller winding angle, a winding angle at the middle section (L2) being kept constant, and a winding angle at the tail section L3 being changed from a smaller winding angle to a larger winding angle, each of the lengths of the head section (L1) and the tail section (L3) being between 25-250 mm, the initial winding angle at the head section (L1) being between 30-90 degrees and being gradually decreased to between 2-30 degrees at the boundary of the head section (L1) and the middle section (L2), the winding angle at the middle section (L2) being kept constant, and the winding angle at the tail section (L3) being gradually increased from between 2-30 degrees at the boundary of the middle section (L2) and the tail section to between 30-90 degrees at the end of the tail section (L3), the winding angles at the head section (L1) and the tail section (L3) being at least two times of the winding angle at the middle section (L2).