Drill crown
US6926104B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 29, 2004 |
| Grant date | Aug 9, 2005 |
| Priority date | — |
| Expiry date | Jan 29, 2024 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/56
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A drill crown (1) used for drilling purposes, especially for rotary percussion drilling of a mouth of a blast furnace. The drill crown (1) consists of a drilling head (4) provided with a plurality of hard material or hard metal inserts (6) and a base body (2) for connection to a drive element etc. in order to drive or impinge upon said drill crown. The hard material or hard metal inserts (6) are received in bores or openings (5) of the drill head (4). According to the invention, at least one hard material or hard metal insert (6) is provided with an at least partially curved or domed surface contour (11) on the end which is received in the drill head (4). Said contour cooperates with a complementary domed or curved surface of the drill head (4) and/or base body (2), whereby the percussive energy required for appropriate drilling power is transmitted in a reliable manner, even when the hard material or hard metal insert (6) is slackened.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.