Title:
拡径用ドリルビット
Document Type and Number:
Japanese Patent JP6697647
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a drill bit for enlarging a diameter which is configured so that large cutting resistance is not generated when starting to rotate.SOLUTION: A drill bit 10 for enlarging a diameter, which enlarges a diameter of a part of a lower hole H by cutting the part, comprises: a plurality of cutting blade portions 21 which are slid to outside in a radial direction by centrifugal force caused by rotation to grind the part of the lower hole H; a cutting blade holding portion 22 which holds slidably the plurality of cutting blade portions 21 individually in a radial direction; and a shank portion 12 that supports the cutting blade holding portion 22. Each of the cutting blade portions 21 has a cutting blade main body 51 formed in a shape in which a part in an axial direction is formed to cut into the lower hole H preceding to the other part, and a rib-like support portion 52 that supports the cutting blade main body 51 from inside and engages slidably with the cutting blade holding portion 22.SELECTED DRAWING: Figure 3
Inventors:
Shogo Fujita
Application Number:
JP2015220697A
Publication Date:
May 27, 2020
Filing Date:
November 10, 2015
Export Citation:
Assignee:
fs technical corporation
International Classes:
B24B33/08; B24D7/18; B28D1/14
Domestic Patent References:
| JP2014223797A | ||||
| JP52086902A | ||||
| JP2005177911A |
Foreign References:
| WO2014129119A1 |
Attorney, Agent or Firm:
Shinryo International Patent Office