US PATENT SUBCLASS 76 / 108.6
.~.~ Twist drill

Current as of: June, 1999
Click HD for Main Headings
Click for All Classes

Internet Version by PATENTEC © 1999      Terms of Use


76 /   HD   METAL TOOLS AND IMPLEMENTS, MAKING

101.1  DF  BLANK OR PROCESS {16}
108.1  DF  .~ Drill {3}
108.6.~.~ Twist drill

DEFINITION

Classification: 76/108.6

Twist drill:

(under subclass 108.1) Invention comprising stock material for, or a method of, making a drill having a solid center and a helically spiralled marginal extent revolved thereabout, and having a radially extending web that continuously connect the solid center and the helically spiraled marginal extent.