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US4067406A Expired / Lapsed US ⏱️ 0.0 years remaining

Soft formation drill bit

Assignee: Smith International Inc
•
Filing: 1976-07-29
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Granted: 1978-01-10
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Expires: 1996-07-29
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Abstract

Abstract A rock bit with rotary cone cutter means having hardened insert teeth utilizing fewer than the normal number of teeth or of cutters used for a given gage hole wherein the cone cutter body is of greater diameter and for approximately the same axial length, of a greater wall thickness and to accommodate a greater insert tooth depth or grip length and permit a proportional increase in extension of the insert from the cutter body to provide greater penetration with fewer insert teeth in contact at a given time, and also providing for increased journal bearing area to increase the life of the extended insert cutters.

Inventors

  • 👤 Lloyd L. Garner
  • 👤 Charles Richard Harris

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 00:49
CPC Classifications
E; E21; E21B; E21B17/00; E21B17/10; E21B17/1092; E21B10/00; E21B10/08; E21B10/16; E21B10/46; E21B10/50; E21B10/52

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 220 words
A drill bit for drilling holes in soft formations such as limestones, shales or the like, comprising: a bit body of given diameter adapted for rotation about an axis within a cylindrical space and having an under side comprising a dome, no more than a pair of journal leg means extending downwardly from said body and having journal means extending downwardly and inwardly within said cylindrical space from the lower end portions of the journal legs beneath said dome, rotary cone cutter body means on said journal means, the approximate slant height line of the surface of the rotary cone cutter body means intermediate the base and apex of the cone where the cutter means is nearest said axis of the bit, is approximately parallel to said axis, hardened insert means imbedded in and extending from said rotary cone cutter body means, said insert means being disposed about said rotary cone cutter body means, and said insert means being of such length that, when the rotary cone cutter body means is in drilling position, at least a portion of said insert means extends outwardly from said surface of the rotary cone cutter body means to intersect the axis of rotation of the bit body while the material of the cone cutter body per se is spaced laterally from said axis.
Claim 2
Dependent Claim 220 words
A drill bit for drilling holes in soft formations such as limestones, shales or the like, comprising: a bit body of given diameter adapted for rotation about an axis within a cylindrical space and having an under side comprising a dome, no more than a pair of journal leg means extending downwardly from said body and having journal means extending downwardly and inwardly within said cylindrical space from the lower end portions of the journal legs beneath said dome, rotary cone cutter body means on said journal means, the approximate slant height line of the surface of the rotary cone cutter body means intermediate the base and apex of the cone where the cutter means is nearest said axis of the bit, is approximately parallel to said axis, hardened insert means imbedded in and extending from said rotary cone cutter body means, said insert means being disposed about said rotary cone cutter body means, and said insert means being of such length that, when the rotary cone cutter body means is in drilling position, at least a portion of said insert means extends outwardly from said surface of the rotary cone cutter body means to intersect the axis of rotation of the bit body while the material of the cone cutter body per se is spaced laterally from said axis.
Claim 3
Dependent Claim 24 words
The structure in claim 1, and in said drilling position, the base of the cone cutter means is approximately as low as its apex.
Claim 4
Dependent Claim 44 words
The structure in claim 1, and the nearest proximity of said rotary cone cutter means to said bit axis along its slant height being approximately vertical, and said inserts being extended from said rotary cone cutter means a minimum of one-quarter of an inch.
Claim 5
Dependent Claim 14 words
The structure in claim 3, and said extension being up to approximately 1 inch.
Claim 6
Dependent Claim 27 words
The structure in claim 1, and said rotary cone cutter means having rows of inserts thereabout, and at least some cutters of a row intersecting said axis.
Claim 7
Dependent Claim 51 words
The structure in claim 1, and said rotary cone cutter means comprising a pair of rotary cone cutters having rows of said inserts thereabout, and some of the hardened inserts of at least one row of inserts of at least one rotary cone cutter intersecting the axis of said bit body.
Claim 8
Dependent Claim 34 words
The structure in claim 1, and said rotary cone cutter means comprising a pair of rotary cone cutters, and some hardened inserts of at least one cone intersecting the axis of said bit body.
Claim 9
Dependent Claim 41 words
The structure in claim 1, and there being essentially two rotary cone cutters, each having rows of hardened inserts thereabout and extending therefrom, and the rows of inserts in one cutter intermeshing with the rows of inserts in the other cutter.
Claim 10
Dependent Claim 36 words
The structure in claim 1, and there being essentially a pair of rotary cone cutters, each having hardened inserts therein and extending therefrom, and the inserts in one cutter intermeshing with those in the other cutter.
Claim 11
Dependent Claim 20 words
The structure in claim 9, and the inserts in both rotary cone cutters intersecting said axis of said bit body.

References Cited (Backward Citations)

US1897588A Cited
US1847824A Cited
US2244617A Cited
US2333746A Cited
US3696876A Cited
US3952815A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-01-09 1981-07-11 1982-01-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-01-09 1985-07-11 1986-01-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-01-09 1989-07-11 1990-01-10 $7700.00 Window Closed / Lapsed

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