Cutting by use of rotating axially moving tool – Tool or tool with support – Having peripherally spaced cutting edges
Patent
1998-05-29
2000-04-18
Bishop, Steven C.
Cutting by use of rotating axially moving tool
Tool or tool with support
Having peripherally spaced cutting edges
761086, 408224, 408229, 408226, 451 48, B23B 5102, B24B 1904
Patent
active
060507543
ABSTRACT:
Significantly improved resistance to breaking while drilling in metal can be realized in twist drill bits having a web thickness taper which is about twice the web thickness taper specified in Standards and in common use in the industry. This creates much shallower flutes and flies in the face of conventional wisdom in the art which holds that the web taper rate should be low to maximize the amount of flute volume available to convey chips and sawdust out of the hole. A flute length of about 1/2" less than the flute lengths specified by the Standards makes it possible to have such a large taper rate but still control variations in tolerances for the flute length. It also provides a marking zone for placing size indicia on the drill bit shank outside the portion which is, ripped by the chuck jaws of a power drill. The use of the new web taper rate, in conjunction with modifications to the tip geometry of a self-centering drill bit with pilot tip, produces a drill bit optimized both for metal and wood drilling which is strong enough to withstand the forces exerted on the bit while drilling in metal using a hand-held power drill, yet which need not be retracted from a 2.times.4 to clear sawdust prior to drilling a hole completely through the thickness of the wood.
REFERENCES:
patent: 460639 (1891-10-01), Holt
patent: 542223 (1895-07-01), Johnson
patent: 1499584 (1924-07-01), Litchfield
patent: 1984839 (1934-12-01), Murray
patent: 2193186 (1940-03-01), Bannister
patent: 2332295 (1943-10-01), Bouchal
patent: 2652083 (1953-09-01), Emmons
patent: 2936658 (1960-05-01), Riley
patent: 3387511 (1968-06-01), Ackart, Sr. et al.
patent: 3592555 (1971-07-01), Mackey, Sr.
patent: 3779664 (1973-12-01), Caley et al.
patent: 4340327 (1982-07-01), Martins
patent: 4529341 (1985-07-01), Greene
patent: 4556347 (1985-12-01), Barish
patent: 4756650 (1988-07-01), Wakihira et al.
patent: 4898503 (1990-02-01), Barish
patent: 4968193 (1990-11-01), Chaconas et al.
patent: 4983079 (1991-01-01), Imanaga et al.
patent: 5011342 (1991-04-01), Hsu
patent: 5056967 (1991-10-01), Hageman
patent: 5088863 (1992-02-01), Imanaga et al.
patent: 5288183 (1994-02-01), Chaconas et al.
patent: 5442979 (1995-08-01), Hsu
Twist Drills Standard (ASME B94.11-M-1993), The American Society of Mechanical Engineers, pp. 1-3, 7-33, 48, 49, 56-59 (Mar. 31, 1994).
National Aerospace Standard (NAS 907) , Aerospace Industries Association of America, Inc. pp. 1-25 (1986).
Introduction to Mechanics of Solids, Popov, Egar P., "Design of Nonprismatic Beams". pp. 360-362 (1968).
Black & Decker 1983-84 Consumer Trade Catalog, Top of p. 28 showing high speed drill bits, (1983) and enlargement.
Bishop Steven C.
Black & Decker Inc.
Yocum Charles E.
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