Bit holder block and cutter bit therefor
US5529384A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 25, 1994 |
| Grant date | Jun 25, 1996 |
| Priority date | — |
| Expiry date | Aug 25, 2014 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21C35/197
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A bit holder block is provided composed of a foot portion for being received in a seat of a rotary member and a bit holder portion for releasably holding a cutter bit with respect to a bit bore therein. The bit bore has a forward opening at a bit abutment face of the bit holder block. The cutter bit is provided with an annular abutment surface for abutting the bit abutment face. A bit retainer port is provided in the bit holder block located at, and communicates with, a rear opening of the bit bore for therein securing a retainer clip to an annular groove in the cutter bit. A rear segment of the bit holder block provides a strong reinforcing structure for the area around the rear opening of the bit bore which counters a fulcrum force generated at the rear opening of the bit bore, the fulcrum force arising during operation due to a resultant force acting on the cutter bit being directed below the axis of the cutter bit, rather than above it, as was previously believed in the art.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.