发明授权
- 专利标题: Twist drill bit
- 专利标题(中): 扭钻钻头
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申请号: US420053申请日: 1995-04-11
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公开(公告)号: US5622462A公开(公告)日: 1997-04-22
- 发明人: Ved Gakhar , David T. Brutscher , Wilfred M. McCord, Jr.
- 申请人: Ved Gakhar , David T. Brutscher , Wilfred M. McCord, Jr.
- 申请人地址: OR Woodburn
- 专利权人: Credo Tool Company
- 当前专利权人: Credo Tool Company
- 当前专利权人地址: OR Woodburn
- 主分类号: B23B51/02
- IPC分类号: B23B51/02
摘要:
A drill bit is provided with a pair of spiral cutting blades having opposed cutting edges which come together at an angle to form a starting tip. Each of the spiral cutting blades includes a spiral flute which extends longitudinally thereof and is provided with a cutting face thereon. Each cutting edge is provided with an inner edge segment and an outer edge segment wherein the inner edge segment extends outwardly from the starting tip a preselected distance and terminates at an inwardly extending inner wall portion of a gullet. The inner wall portion of the gullet is arcuate in structure and terminates at a preselected inward position with an outer wall of the gullet. The outer wall of the gullet extends angularly outwardly terminating at the intersection with an outer segment of the cutting edge. The outer edge segment of the cutting edge is defined by the outward terminating end of the outer wall of the gullet and the outer most extremity of the cutting edge.
公开/授权文献
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