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:
Dec. 28, 2010
Filed:
May. 03, 2005
Masafumi Nishitani, Kawasaki, JP;
Hisashi Yamagishi, Hanno, JP;
Makoto Kubota, Kawaguchi, JP;
Koki Motoyoshi, Hanno, JP;
Masafumi Nishitani, Kawasaki, JP;
Hisashi Yamagishi, Hanno, JP;
Makoto Kubota, Kawaguchi, JP;
Koki Motoyoshi, Hanno, JP;
Bridgestone Sports Co., Ltd., Tokyo, JP;
Abstract
An iron-type golf club head has a face which has a face surface of a flat shape, and a hosel which is continuous with the face on its heel side. A shaft insertion hole is disposed in the hosel. A protrusion protruding rearward is disposed in the vicinity of the center in a toe-heel direction. A material of the golf club head is pure iron having a high purity of at least 99.8%, for instance, pure iron having a purity within a range of 99.995 to 99.9999%. The golf club head is subjected to carburizing so that carbon diffuses up to about 0.2 to 0.5 mm from the surface. A region within 0.2 mm from the face surface has a hardness of HV 300 to 600, and a region where a distance from the face surface is 0.7 mm or more has a hardness of HV 100 or lower.