Drill structure
US10596641B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 20, 2017 |
| Grant date | Mar 24, 2020 |
| Priority date | — |
| Expiry date | Apr 25, 2037 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23B2251/24
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A drill structure includes a shank part and a flute part arranged on one end of the shank part. A chisel edge is formed on the front end of the flute part and two drill blades with tilt directions toward the shank part are symmetrically formed on the two sides of the chisel edge. Every drill blade includes: a primary relief surface with a cutting edge, a first connecting edge and a first chamfering edge, a secondary relief surface with a knife-back edge, a second connecting edge, a second chamfering edge and an outer edge, and an assist relief surface. The second connecting edge joins to the first connecting edge, and the second chamfering edge connects with the first chamfering edge. The assist relief surface, which tilts toward the shank part the, is extend from the first chamfering edge and the second chamfering edge. This drill structure can improve the surface finish of the drilling hole.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.