Sawtooth structure with reversed cutting function and its drill series
US10857601B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 18, 2016 |
| Grant date | Dec 8, 2020 |
| Priority date | — |
| Expiry date | Aug 31, 2036 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23B2251/285
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A kind of sawtooth structure with reversed cutting function and its drill series are presented in this invention. This invention is suitable for drilling low-damage holes on carbon fiber reinforced polymers (CFRP). The sawtooth structure is comprised of sawteeth and grooves located on the cutting edges of drill. And the sawtooth structure is helically arranged with a specific helix angle around the axis of the drill. It can be classified as the left-hand helix sawtooth structure and the right-hand helix sawtooth structure based on the helix angle value. The bottom edges of the left-hand helix sawtooth structure are the cutting edges, and the rake angles are positive; while the top edges of the right-hand helix sawtooth are the cutting edge with the positive rake angles. The sawtooth structure can be applied to various drilling tools, which proves to be universal. And it can effectively reduce delamination at both hole entrance and hole exit as well as burrs defects. The series of drilling tools include the double point angle drill, the twist drill and the stepped drill all of which have the sawtooth structure on the cutting edges. These series of drilling tools can achieve the CFRP…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.