← Back to Patent Explorer
US5078219A Expired / Lapsed US ⏱️ 0.0 years remaining

Concave drag bit cutter device and method

Assignee: United States Department of the Interior
•
Filing: 1990-07-16
•
Granted: 1992-01-07
•
Expires: 2010-07-16
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A concave drag bit cutter device and cutting method using such a concave cutter bit are provided which provide substantially increased efficiencies over conventional point attack bits. A number of different cutter bit shapes employing a concave cutting face can be used. The cutter bits are intended to replace the conventional point attack cutter bits and can be used in continuous mining machines, saw blades, auger drills, longwall shearers and the like, in cutting and mining operations.

Inventors

  • 👤 Roger J. Morrell
  • 👤 David A. Larson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 20:56
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/44; B; B28; B28D; B28D1/00; B28D1/02; B28D1/12; B28D1/18; B28D1/186; B28D1/188; E21B10/08; E21B10/12; E21B10/46; E21B10/56; E21C; E21C35/00; E21C35/18; E21C35/183; E21C35/1837

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 92 words
A cutter bit assembly for use in a non-percussive excavation machine, said assembly being rotated during a cutting operation and comprising a replaceable cutter insert and a circular shank in which said insert is mounted, the improvement wherein said cutter insert comprises a cutter bit which, in use, extends generally transversely to a wall being cut and which rotates to provide cutting of the wall, said cutter bit comprising a continuous leading face portion having central concavity therein and defining with a circular edge of said cutter bit a concave cutting surface.
Claim 2
Dependent Claim 92 words
A cutter bit assembly for use in a non-percussive excavation machine, said assembly being rotated during a cutting operation and comprising a replaceable cutter insert and a circular shank in which said insert is mounted, the improvement wherein said cutter insert comprises a cutter bit which, in use, extends generally transversely to a wall being cut and which rotates to provide cutting of the wall, said cutter bit comprising a continuous leading face portion having central concavity therein and defining with a circular edge of said cutter bit a concave cutting surface.
Claim 3
Dependent Claim 18 words
A cutter bit assembly as claimed in claim 1 wherein said cutter insert comprises a constant angle face.
Claim 4
Dependent Claim 17 words
A cutter bit assembly as claimed in claim 1 wherein said cutter insert comprises a curved face.
Claim 5
Dependent Claim 17 words
A cutter bit assembly as claimed in claim 1 wherein said cutter insert comprises a combination face.
Claim 6
Dependent Claim 115 words
In a non-percussive excavation machine, a cutterhead assembly comprising a cutterhead and a plurality of bit holders mounted on said cutterhead and a plurality of bit assemblies each received in a respective one of said bit holders, each said bit assembly comprising a replaceable cutter insert and a circular cutter shank in which said insert is mounted, the improvement wherein said cutter insert comprises a cutter bit which, in use, extends generally transversely to a wall being cut and which rotates to provide cutting of the wall, said cutter bit comprising a continuous leading face portion having a central concavity therein and defining with a circular edge of said cutter bit a concave cutting surface.
Claim 7
Dependent Claim 115 words
In a non-percussive excavation machine, a cutterhead assembly comprising a cutterhead and a plurality of bit holders mounted on said cutterhead and a plurality of bit assemblies each received in a respective one of said bit holders, each said bit assembly comprising a replaceable cutter insert and a circular cutter shank in which said insert is mounted, the improvement wherein said cutter insert comprises a cutter bit which, in use, extends generally transversely to a wall being cut and which rotates to provide cutting of the wall, said cutter bit comprising a continuous leading face portion having a central concavity therein and defining with a circular edge of said cutter bit a concave cutting surface.
Claim 8
Dependent Claim 18 words
A cutter head arrangement as claimed in claim 5 wherein said cutter insert comprises a constant angle face.
Claim 9
Dependent Claim 17 words
A cutter head arrangement as claimed in claim 5 wherein said cutter insert comprises a curved face.
Claim 10
Dependent Claim 17 words
A cutter head arrangement as claimed in claim 5 wherein said cutter insert comprises a combination face.

References Cited (Backward Citations)

US3856359A Cited
US4678237A Cited
US4593777A Cited
US4783123A Cited
US4906294A Cited
US4911254A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-01-06 1995-07-08 1996-01-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-01-06 1999-07-08 2000-01-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-01-06 2003-07-08 2004-01-07 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag