发明授权
- 专利标题: Rotary-percussion drill with a four-start helical shaft
- 专利标题(中): 旋转冲击钻具有四开式螺旋轴
-
申请号: US11796737申请日: 2007-04-27
-
公开(公告)号: US07628232B2公开(公告)日: 2009-12-08
- 发明人: Olaf Koch , Josef Starkmann , Guenther Domani
- 申请人: Olaf Koch , Josef Starkmann , Guenther Domani
- 申请人地址: LI Schaan
- 专利权人: Hilti Aktiengesellschaft
- 当前专利权人: Hilti Aktiengesellschaft
- 当前专利权人地址: LI Schaan
- 代理机构: Abelman, Frayne & Schwab
- 优先权: DE102006000208 20060428
- 主分类号: E21B10/44
- IPC分类号: E21B10/44
摘要:
A rotary-percussion drill includes a four-start helical shaft (3) having a fourfold rotationally and mirror-symmetrical helix cross-section, with radially projecting convexly formed helical webs (4) extending from a concave groove bottom (5) up to the envelope circle (6) and having an undercut (7) with respect to a web width (S).
公开/授权文献
- US20070251734A1 Rotary-percussion drill with a four-start helical shaft 公开/授权日:2007-11-01
信息查询