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:
Apr. 27, 1993
Filed:
Sep. 26, 1991
Applicant:
Inventors:
Assignee:
Yamaha Corporation, Hamamatsu, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
A63B / ;
U.S. Cl.
CPC ...
2731 / ; 273 78 ;
Abstract
A hollow metallic wood club head formed of a superplastic metallic material to have a crown portion, a hitting face portion and a sole portion, wherein the rigidity of the crown portion is determined to be lower than that of the sole portion so that the loft angle of the face portion is increased at the moment of impact against a golf ball in an angle range of 0.5.degree.-2.5.degree., and wherein the metallic average grain size of the crown portion is determined to be less than 50 micron.