Drill bit with concave spurs and having triangular center point with vee grooves
US5061127A · kind A · utility
Inventor
Key dates
| Filing date | Apr 5, 1991 |
| Grant date | Oct 29, 1991 |
| Priority date | — |
| Expiry date | Apr 5, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T408/9065
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
An improved drill bit for wood boring or boring in other relatively soft material, having a generally cylindrical shaft (20), with a flattened blade portion at one end (24). The blade portion (24) is broad and flat with essentially parallel side surfaces (41, 42) and having negatively beveled edges along the length of such side surfaces, such side surfaces giving way to a modified end edge. The modified end edge includes a center point, with a length of one half to several times the thickness of the blade, and said point (34) is centered on the end edge and is made with a triangular shape with a vee groove from the center of the base to the middle of the vertex. (35). Outer spurs of rectangular cross section (29 and 30) with a concave tip and a negative bevel away from the leading edge are located on the lateral extremities of the end edge. Radially extending cutting surfaces (45 and 46) with a negative bevel away from the leading edge (37 and 38) extend at right angles from the base of the center point to the inside edge of the outer spurs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.