Thomas D Quinn

US Patent:

7861807, Jan 4, 2011

Filed:

Dec 3, 2008

Appl. No.:

12/327110

Inventors:

Florian Probst - Hutthurm, DE
Thomas J. Quinn - Towson MD, US
William R. Stumpf - Kingsville MD, US
Albert Leidl - Passau, DE
Rudolf Jungwirth - Hutthurm, DE

Assignee:

Black & Decker Inc. - Newark DE

International Classification:

E21B 10/36

US Classification:

175420, 175415

Abstract:

A cutting head for a drill bit has a body with an overall cruciform shape. One pair of opposing arms defines a main cutting edge. The other pair of opposing arms defines an auxiliary edge. The main cutting edge is defined by rake surfaces and relief surfaces. Each rake surface and relief surface is defined by a plurality of facets. The main cutting edge includes a chisel edge. A first pair of planar rake facets, one on each end of said chisel edge, and a first pair of planar relief facets, adjacent said chisel edge, defines a portion of the cutting edge. A remaining portion of the main cutting edge is defined at the apex of a plurality of curved rake facets and curved relief facets. The auxiliary edge is defined by a plurality of curved surfaces.

US Patent:

D689755, Sep 17, 2013

Filed:

Sep 23, 2011

Appl. No.:

29/402433

Inventors:

Thomas J. Quinn - Towson MD, US
David B. Lee - Baltimore MD, US
Maurice Lapointe - Ellicott City MD, US
Glen V. Steinbrunner - Bel Air MD, US

Assignee:

Black & Decker Inc. - Newark DE

International Classification:

0803

US Classification:

D 8 70, D8 47

US Patent:

20120301238, Nov 29, 2012

Filed:

Mar 21, 2012

Appl. No.:

13/425751

Inventors:

Thomas J. Quinn - Towson MD, US
David N. Johnson - South Yorkshire, GB
Florian Probst - Freising, DE

Assignee:

BLACK & DECKER INC. - Newark DE

International Classification:

B25D 17/02
B28D 1/26
C21D 8/00

US Classification:

408199, 148516, 125 40

Abstract:

A point chisel includes a substantially cylindrical shank and a working end region that tapers to a point. The working end region has at least three converging substantially planar surfaces, each with a protruding elongate rib extending along at least part of its length. Adjacent surfaces meet along at least part of their length at substantially straight edges between adjacent ribs. A flat chisel includes a substantially cylindrical shank and a working end region with a pair of converging substantially planar surfaces that include a plurality of protruding elongate ribs extending along at least part of its length. Each rib has, along the majority of its length, a substantially constant height above the surface from which it protrudes. Each chisel is made from steel, with the shank having a bainitic microstructure and the working end region having a martensitic microstructure.