Twist drill bit
AssigneeApex Brands, Inc.
InventorLaVerne Royal Durfee
Life of this patent
Estimating the term…
Abstract
A boring tool may include a coupling portion for interfacing with a powered driver, a shank operably coupled to the coupling portion, a cutting portion operably coupled to the shank, and a cutting tip operably coupled to a distal end of the cutting portion relative to the shank. The coupling portion, the shank, the cutting portion and the cutting tip share an axis. The cutting portion may be defined by a plurality of helical cutting flutes that have a variable rate that increases as distance from the cutting tip increases. The shank may include a torsion zone and the cutting tip may include a point angle between about 120 degrees and about 90 degrees.
Claims20
A boring tool comprising:
- a coupling portion for interfacing with a powered driver;
- a shank operably coupled to the coupling portion;
- a cutting portion operably coupled to the shank;
- and
- a cutting tip operably coupled to a distal end of the cutting portion relative to the shank,
- wherein the coupling portion, the shank, the cutting portion and the cutting tip share an axis,
- wherein the cutting portion is defined by a plurality of helical cutting flutes that have a variable rate that increases as distance from the cutting tip increases,
- wherein the shank comprises a torsion zone;
- and
- wherein the cutting tip comprises a point angle between about 120 degrees and about 90 degrees.
The boring tool of claim 8, wherein a width of grooves of the helical cutting flutes decreases as distance from the cutting tip increases.
A method of making a boring tool, the method comprising:
- machining the boring tool such that the boring tool includes a coupling portion, a cutting tip, a shank, and a cutting portion sharing an axis;
- machining the cutting portion to define helical cutting flutes that extend from the cutting tip to the shank;
- machining a torsion zone in the shank;
- and
- machining the cutting tip to define a point angle between about 120 degrees and about 90 degrees,
- wherein the helical cutting flutes that have a variable rate that increases as distance from the cutting tip increases.
A boring tool comprising:
- a coupling portion for interfacing with a powered driver;
- a shank operably coupled to the coupling portion;
- a cutting portion operably coupled to the shank;
- and
- a cutting tip operably coupled to a distal end of the cutting portion relative to the shank,
- wherein the coupling portion, the shank, the cutting portion and the cutting tip share an axis,
- wherein the cutting portion is defined by a plurality of helical cutting flutes that have a variable rate that increases as distance from the cutting tip increases,
- wherein the shank comprises a portion having a reduced diameter that is 80% to 95% of a diameter of other portions of the shank to absorb shock from an impact driver;
- and
- wherein the cutting tip comprises a point angle between about 110 degrees and about 100 degrees.
Dependencies are inferred from the claim text.