Title:
DRILL
Document Type and Number:
Japanese Patent JP2019005882
Kind Code:
A
Abstract:
To provide a drill in which the strength of the blade edge of the radially inside end part of a thinning cutting blade part can be improved, thereby preventing, for example, damage to a chisel, making it possible to stably carry out a highly accurate drilling process.SOLUTION: In a cutting blade 4, a thinning cutting blade part 9 located at least radially inside is a honing blade. The position where the honing width of the thinning cutting blade part 9 is maximum is radially outside the position of a length X×(1/6), which is from the radially inside end of the thinning cutting blade part 9 to the radially outside end thereof, if the blade length of the thinning cutting blade part 9 is X, and is radially inside the position of a length X×(1/3). The maximum value of the honing width of the thinning cutting blade part 9 is equal to or greater than 1.5 times of the honing width, at the radially outside end, of the thinning cutting blade part 9.SELECTED DRAWING: Figure 4
Inventors:
FUJIWARA SHIGEYOSHI
NIWA TERUAKI
HARA YUSUKE
NIWA TERUAKI
HARA YUSUKE
Application Number:
JP2017126666A
Publication Date:
January 17, 2019
Filing Date:
June 28, 2017
Export Citation:
Assignee:
MITSUBISHI HITACHI TOOL ENG LTD
International Classes:
B23B51/00
Attorney, Agent or Firm:
Yasushi Matsunuma
Mitsuo Teramoto
Fumihiro Hosokawa
Kazunori Onami
Mitsuo Teramoto
Fumihiro Hosokawa
Kazunori Onami