The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 31, 1995
Filed:
Apr. 24, 1992
Akira Noguchi, Tokyo, JP;
Daiwa Golf Co., Ltd., Tokyo, JP;
Abstract
A golf club shaft comprising a mandrel with a tapered surface as its outer circumference which is wound with three layers of prepreg sheets of high-strength fiber impregnate with synthetic resin. The middle layer is also wound with a separate string member. The inner layer fibers and the separate string member are arranged in a criss-cross pattern running generally in the longitudinal axial direction of the shaft. However, the fibers which are part of the middle and outer layers run unidirectionally only in the longitudinal axial direction of the shaft. No fibers run in a circumferential direction. In addition, the fiber and matrix of the outer layer become transparent after curing. Thus, even when the shaft is shrunk toward the center, no zigzag or wrinkles are generated in the string member found between the middle and outer layers nor in the outer layer fibers themselves. Also, no zigzagging, wrinkling, sagging or whitening occurs in the transparent outer layer which allows the design pattern of the string member to be seen. This increases the strength of the shaft and sufficient clamping stress by taping is provided. Finally, the safety of the club shaft is increased because the outer layer prevents exposure of the fibers and string member which decreases the chance of breakage.