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US4143920A Expired / Lapsed US ⏱️ 0.0 years remaining

Mineral cutting pick insert shape

Assignee: Hydra Tools International PLC
•
Filing: 1978-03-07
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Granted: 1979-03-13
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Expires: 1998-03-07
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Abstract

Abstract A mineral cutting pick of the type adapted to be traversed relative to a mineral face and having a leading cutting edge and an outer cutting edge incorporated in a hard metal insert mounted in a rebate formed by a pair of seating surfaces at the end of a pick body remote from a shank for use in securing in a socket of a chain or drum or the like, wherein at least one end of the leading cutting edge adjacent the outer cutting edge has negative rake with respect to the shank, and the leading cutting edge is defined by surfaces the angle between which increases from the position at which it will make foremost contact with the mineral face to the end of the leading cutting edge adjacent the outer cutting edge, whereby a sharper angle for the leading cutting edge is provided where it will attack the mineral face and a blunter angle is provided towards the end adjacent the outer cutting edge to afford greater strength as the insert decreases in transverse width towards the outer cutting edge.

Inventors

  • 👤 John W. Haddock

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 10:24
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/46; E21B10/58; E21C; E21C35/00; E21C35/18; E21C35/183; E21C35/1837

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 133 words
A mineral cutting pick of the type adapted to be traversed relative to a mineral face and having a leading cutting edge and an outer cutting edge incorporated in a hard metal insert mounted in a rebate formed by a pair of seating surfaces at the end of a pick body remote from a shank for use in securing in a socket of a chain or drum or the like, at least one end of the leading cutting edge adjacent the outer cutting edge having negative rake with respect to the shank, and the leading cutting edge being defined by surfaces the angle between which increases from the position at which it will make foremost contact with the mineral face to the end of the leading cutting edge adjacent the outer cutting edge.
Claim 2
Dependent Claim 133 words
A mineral cutting pick of the type adapted to be traversed relative to a mineral face and having a leading cutting edge and an outer cutting edge incorporated in a hard metal insert mounted in a rebate formed by a pair of seating surfaces at the end of a pick body remote from a shank for use in securing in a socket of a chain or drum or the like, at least one end of the leading cutting edge adjacent the outer cutting edge having negative rake with respect to the shank, and the leading cutting edge being defined by surfaces the angle between which increases from the position at which it will make foremost contact with the mineral face to the end of the leading cutting edge adjacent the outer cutting edge.
Claim 3
Dependent Claim 15 words
A mineral cutting pick as in claim 1, wherein the leading cutting edge is straight.
Claim 4
Dependent Claim 16 words
A mineral cutting pick as in claim 1, wherein the leading cutting edge is convexly curved.
Claim 5
Dependent Claim 15 words
A mineral cutting pick as in claim 1, wherein the leading cutting edge is angular.
Claim 6
Dependent Claim 16 words
A mineral cutting pick as in claim 1, wherein the leading edge is a sharp edge.
Claim 7
Dependent Claim 14 words
A mineral cutting pick as in claim 1, wherein the leading edge is rounded.
Claim 8
Dependent Claim 32 words
A mineral cutting pick as in claim 1, wherein the leading edge is provided with a flat or flats of transverse width small in relation to the overall width of the insert.
Claim 9
Dependent Claim 22 words
A mineral cutting pick as in claim 1, wherein the outer cutting edge is defined by a pair of convexly curved surfaces.
Claim 10
Dependent Claim 29 words
A mineral cutting pick as in claim 8, wherein the adjacent part of the pick body is provided with surfaces merging with the surfaces defining the outer cutting edge.
Claim 11
Dependent Claim 45 words
A mineral cutting pick as in claim 8, wherein the part of the pick body adjacent the leading cutting edge is provided with surfaces inclined to each other at the same angle as between the adjacent ends of the surfaces defining the leading cutting edge.

References Cited (Backward Citations)

GB976538A Cited
GB1333401A Cited
SU381753A1 Cited
GB1348488A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-03-12 1982-09-11 1983-03-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-03-12 1986-09-11 1987-03-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-03-12 1990-09-11 1991-03-13 $7700.00 Window Closed / Lapsed

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