Golf club shaft
AssigneeSRI Sports Limited
InventorTomio Kumamoto
Life of this patent
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Abstract
A golf club shaft composed of a laminate of a plurality of carbon fiber reinforced prepreg sheets having a length equal to the full length of the golf club shaft and are sequentially wound round a mandrel. Per-area weights of the carbon fibers of the carbon fiber prepreg sheets having the length equal to the full length of the golf club shaft are gradually increased from an innermost-layer CF prepreg sheet to an outermost-layer carbon fiber prepreg sheet in such a way that the per-area weight of the outermost-layer carbon fiber prepreg sheet is set larger than that of the innermost-layer CF prepreg sheet.
Claims6
A golf club shaft comprising a plurality of at least three resin sheets, reinforced with carbon fibers, which have a length equal to a full length of said golf club shaft and are sequentially wound around a mandrel,
- wherein said resin sheets reinforced with said carbon fibers are composed of carbon fiber prepreg sheets formed by impregnating said carbon fibers arranged properly in one direction with a resin;
- wherein in all carbon fiber prepreg sheets which have a length equal to a full length of said golf club shaft, a per-area weight of said carbon fiber in each of said all carbon fiber prepreg sheets is more than a per-area weight of said carbon fiber in the adjacent inner layer carbon fiber prepreg sheet from an innermost-layer to an outermost layer;
- and
- wherein a per-area weight of said carbon fiber of said outermost-layer prepreg sheet is CFn, a per-area weight of the said carbon fiber of said innermost-layer prepreg sheet is CF1, and the number of said carbon fiber prepreg sheets each having a length equal to said full length of said golf club shaft is N, such that (CFn/CF1)/N is set to a range of 0.7 to 1.25.
Dependencies are inferred from the claim text.