PURPOSE: To provide a lightweight golf club shaft which has a sufficiently high twisting strength by including reinforcing fibers in a bias layer of club shaft, and composing the reinforcing fibers so that fibers having higher compression strength are contained more on the head side and fibers having lower compression strength are contained more on the grip side.
CONSTITUTION: The surface of a mandrel 1 is subjected to a die removal process, and adhesives are applied. A high strength PAN series carbon fiber unidirectional prepreg. as a head side bias layer 2 and a high elasticity pitch series carbon fiber unidirectional prepreg as the grip side bias layer 3 are spliced so that a hybrid prepreg 4 for bias layer is accomplished. The hybrid prepregs 4 are overlapped so that the carbon fiber orientation direction is at a certain angle, for example 40deg., to the shaft axial direction, and then wound ±2 plies. Then, as a straight layer 5, a PAN series carbon fiber unidirectional prepreg is wound three plies so that the carbon fiber orientation direction becomes parallel with the shaft axial direction, and this is subjected to heating and hardening.
JPS60184567 | [Title of the device] Golf club |
JP2000288141 | GOLF CLUB SHAFT |
JP2003199852 | GOLF CLUB SHAFT |
MITOMA MASATAKA