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:
Nov. 13, 2001
Filed:
Oct. 27, 1999
Toru Sekiguchi, Ohyamamachi, JP;
Yoshiro Suzuku, Toyama, JP;
Nachi-Fujikoshi Corporation, Toyama, JP;
Abstract
An improved twist drill is provided which reduces wear or chippings of the major cutting edges (,) and those of the leading edges (,) of land (,) and which has a long service life and stays sharp. A twist drill has a pair of chip discharge flutes (,), a pair of chisel edges (,), a pair of inner cutting edges (,) and a pair of major cutting edges (,) extending from each outer end of the inner cutting edges (,). Further, the drill has a pair of outer cutting edges (,) each receding from each of the major cutting edges (,) at an angle (&agr;,), and a pair of leading edges (,) of lands (,) each formed by the land (,) and the outer cutting edge (,) and has a linear or curved rake face (,). Wherein, an angle (&agr;,) of the leading edge (,) of land (,) between the leading edge (,) of the land (,) between the leading edge (,) of the land (,) and the linear or curved rake face (,) is an obtuse angle.