US5078219A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Concave drag bit cutter device and method
Assignee: United States Department of the Interior
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Filing: 1990-07-16
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Granted: 1992-01-07
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Expires: 2010-07-16
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)
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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 |