Drill bit point
OwnerJames E. Musacchiainventor
Life of this patent
Estimating the term…
Abstract
A drill bit is provided having a novel drill point for drilling a variety of materials. The drill point comprises at least two opposed cutting edges, the cutting edges forming a predetermined drill point angle. The cutting edges have a first radial component between the extreme tip of the drill point and their respective lands. The first radial component is substantially concave. The cutting edges have a second radial component defined generally where the cutting edge merges with its respective land, the second radial component being substantially convex. The drill point of the invention can be applied to any variety of drill bit or cutting tool having any number of flutes, or may comprise a replaceable drill point. A method is also provided for forming the novel drill point according to the invention.
Claims20
A drill point for use on any variety of drill bits, said drill point comprising:
- at least two substantially opposed cutting edges, said cutting edges forming a predetermined drill point angle;
- each said cutting edge having a first substantially flat component at the tip thereof;
- a second radial component merging from said first flat component, said second radial component being substantially concave with respect to a plane drawn perpendicular to the longitudinal axis of said drill point;
- and
- a third radial component defined generally where said cutting edge merges with its respective land, said third radial component being substantially convex with respect to a plane drawn perpendicular to the longitudinal axis of said drill point.
A drill bit for drilling a variety of materials, said drill bit comprising:
- a plurality of lands, said lands defining flutes;
- at least two cutting edges defined by at least two of said lands, said cutting edges having a substantially flat component at the tip thereof forming a predetermined drill point angle;
- each said cutting edge having a first substantially concave radial component merging from said flat component;
- and
- a corner where said cutting edge merges with its respective said land, said corner having a substantially convex radial component merging from said concave radial component.
A method for forming a drill bit having an extended wear drill point, said method comprising the steps of:
- forming a blank into a drill bit having at least two flutes;
- forming a cutting edge onto the drill bit;
- forming a flat component at the tip of each cutting edge;
- forming a first concave radial component into the cutting edge profile, the first concave radial component merging from the flat component at the cutting edge tip;
- and
- forming a second convex radial component into the corner of the cutting edge and its respective land.
Dependencies are inferred from the claim text.