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:
May. 14, 1996
Filed:
Dec. 22, 1994
Yoshihiro Natsume, Shizuoka, JP;
Yamaha Corporation, , JP;
Abstract
In production of a tennis or badminton racket frame in a mould under application of heat with pressure, an impervious tube is inserted into an FRP tubular material, a pair of such tubular materials are arranged in a spaced juxtaposition in the mould, a string guide strip having transverse, through string holes is inserted between the pair off tubular materials with it string holes being directed normal to the juxtaposition, and internal pressure is applied into the tubular materials during application of heat with pressure. Formation of the string holes is carried out concurrently with mould shaping of the racket frame, thereby greatly simplifying the process with reduction in cost. Absence of the conventional string hole drilling results in smooth opening of the string holes in the end product, thereby avoiding undesirable string breakage during setting under tension to the head of the racket frame.