US4538690A
Expired / Lapsed
US
⏱️ 0.0 years remaining
PDC cutter and bit
Assignee: ReedHycalog LP
•
Filing: 1983-02-22
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Granted: 1985-09-03
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Expires: 2003-02-22
Abstract
Abstract The invention comprises a drag-type drill bit and a cutting member therefor. Each of the cutting members comprises a stud having a shank adjacent one end mounted in a respective bore in the bit body and a head adjacent the opposite end projecting outwardly from the bit body. The head has a lip formation adjacent the juncture of the head and shank. The lip extends laterally outwardly with respect to the shank to overly the outer surface of the bit body adjacent the respective bore. The cutting face is concave, presenting a plurality of different back rake angles, which angles increase with distance from the lip formation.
Inventors
- 👤 Lot W. Short, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 02:05
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/46; E21B10/56; E21B10/567; E21B10/5673; E21B10/573
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
159 words
A cutting member for mounting on a drill bit comprising: an elongate body comprised of sintered tungsten carbide, said elongate body having a mounting portion adjacent one end, said mounting portion being adapted to be received in a bore in a drill bit body, and an operating portion adjacent the opposite end, said operating portion being adapted to project outwardly from said drill bit body when said mounting portion is so received in such bore, and said operating portion having a lip formation adjacent the juncture of said mounting and operating portions, said lip formation extending laterally outwardly with respect to said mounting portion whereby it may overly the outer surface of such bit body adjacent such bore when said mounting portion is so received therein, and said lip formation defining a shoulder facing axially toward said one end of said elongate body, and wherein said operating portion is flared radially outwardly to the outer edge of said shoulder.
Claim 2
Dependent Claim
159 words
A cutting member for mounting on a drill bit comprising: an elongate body comprised of sintered tungsten carbide, said elongate body having a mounting portion adjacent one end, said mounting portion being adapted to be received in a bore in a drill bit body, and an operating portion adjacent the opposite end, said operating portion being adapted to project outwardly from said drill bit body when said mounting portion is so received in such bore, and said operating portion having a lip formation adjacent the juncture of said mounting and operating portions, said lip formation extending laterally outwardly with respect to said mounting portion whereby it may overly the outer surface of such bit body adjacent such bore when said mounting portion is so received therein, and said lip formation defining a shoulder facing axially toward said one end of said elongate body, and wherein said operating portion is flared radially outwardly to the outer edge of said shoulder.
Claim 3
Dependent Claim
22 words
A cutting member according to claim 1, wherein said shoulder extends around the major portion of the circumference of said elongate body.
Claim 4
Dependent Claim
35 words
A cutting member according to claim 1 wherein said operating portion has a cutting face thereon, said cutting face having a plurality of back rake angles becoming less negative with distance from said lip formation.
Claim 5
Dependent Claim
13 words
A cutting member according to claim 3 being a self-sharpening type cutting member.
Claim 6
Dependent Claim
33 words
A cutting member according to claim 4 wherein said cutting face is defined by a layer of material carried on said elongate body and substantially harder than the material of said elongate body.
Claim 7
Dependent Claim
17 words
A cutting member according to claim 5 wherein said layer defining said cutting face comprises polycrystalline diamond.
Claim 8
Dependent Claim
15 words
A cutting member according to claim 5 wherein said cutting face is curved, concave outwardly.
Claim 9
Dependent Claim
40 words
A cutting member according to claim 7 wherein said cutting face has an original cutting edge disposed axially outermost and generally intersecting the centerline of said elongate body, the remainder of said cutting face being laterally offset from said centerline.
Claim 10
Dependent Claim
39 words
A cutting member according to claim 7 wherein said cutting face is curved in planes in which back rake angle can be measured but substantially straight in planes normal to those in which back rake angle can be measured.
Claim 11
Dependent Claim
17 words
A cutting member according to claim 9 wherein said cutting face defines a portion of a cylinder.
Claim 12
Dependent Claim
20 words
A cutting member according to claim 10 wherein said original cutting edge has a back rake angle of approximately 0°.
Claim 13
Dependent Claim
24 words
A cutting member according to claim 11 wherein said elongate body is comprised of sintered tungsten carbide, and said superhard material comprises polycrystalline diamond.
Claim 14
Dependent Claim
15 words
A cutting member according to claim 12 wherein said cutting face is curved, concave outwardly.
Claim 15
Dependent Claim
40 words
A cutting member according to claim 13 wherein said cutting face is curved in planes in which back rake angle can be measured, but is substantially straight in planes normal to those in which back rake angle can be measured.
Claim 16
Dependent Claim
17 words
A cutting member according to claim 14 wherein said cutting face defines a portion of a cylinder.
Claim 17
Dependent Claim
32 words
A cutting member according to claim 12 wherein said original cutting edge generally intersects the centerline of said elongate body, the remainder of said cutting face being laterally offset from said centerline.
Claim 18
Dependent Claim
86 words
A self-sharpening cutting member for mounting on a drag-type drill bit comprising: an elongate body and a layer of superhard material carried on said body and defining a cutting face adjacent one end of said body, said cutting face having an original cutting edge disposed axially outermost and having a plurality of back rake angles becoming more negative from said original cutting edge axially inwardly, a tangent to said cutting face at said original cutting edge lying in a plane passing longitudinally through said elongate body.
Claim 19
Dependent Claim
86 words
A self-sharpening cutting member for mounting on a drag-type drill bit comprising: an elongate body and a layer of superhard material carried on said body and defining a cutting face adjacent one end of said body, said cutting face having an original cutting edge disposed axially outermost and having a plurality of back rake angles becoming more negative from said original cutting edge axially inwardly, a tangent to said cutting face at said original cutting edge lying in a plane passing longitudinally through said elongate body.
Claim 20
Dependent Claim
72 words
A cutting member for mounting on a drill bit comprising: an elongate body comprised of sintered tungsten carbide, said elongate body having a stud-like mounting portion adjacent one end and an operating portion adjacent the opposite end, said body having a shoulder adjacent the juncture of said mounting and operating portions and facing axially toward said one end, and said operating portion flaring radially outwardly to the outer edge of said shoulder.
Claim 21
Dependent Claim
72 words
A cutting member for mounting on a drill bit comprising: an elongate body comprised of sintered tungsten carbide, said elongate body having a stud-like mounting portion adjacent one end and an operating portion adjacent the opposite end, said body having a shoulder adjacent the juncture of said mounting and operating portions and facing axially toward said one end, and said operating portion flaring radially outwardly to the outer edge of said shoulder.
Claim 22
Dependent Claim
22 words
A cutting member according to claim 18 wherein said shoulder extends around the major portion of the circumference of said elongate body.
Claim 23
Dependent Claim
25 words
A cutting member according to claim 19 further comprising a layer of superhard material carried on said operating portion and defining a concave cutting face.
Claim 24
Dependent Claim
139 words
A drag-type drill bit comprising: a bit body; a plurality of cutting members mounted on said bit body, each of said cutting members comprising an elongate body comprised of sintered tungsten carbide, said elongate body having a mounting portion adjacent one end brazed into a respective bore in said bit body, and an operating portion adjacent the opposite end projecting outwardly from said bit body, said operating portion having a lip formation adjacent the juncture of said mounting and operating portions, said lip formation extending laterally outwardly with respect to said mounting portion and overlying the outer surface of said bit body adjacent the respective bore and thereby shielding the brazed interface between said mounting body of said bit body, said lip formation forming an obtuse angle with the surface of said bit body outwardly of said lip formation.
Claim 25
Dependent Claim
139 words
A drag-type drill bit comprising: a bit body; a plurality of cutting members mounted on said bit body, each of said cutting members comprising an elongate body comprised of sintered tungsten carbide, said elongate body having a mounting portion adjacent one end brazed into a respective bore in said bit body, and an operating portion adjacent the opposite end projecting outwardly from said bit body, said operating portion having a lip formation adjacent the juncture of said mounting and operating portions, said lip formation extending laterally outwardly with respect to said mounting portion and overlying the outer surface of said bit body adjacent the respective bore and thereby shielding the brazed interface between said mounting body of said bit body, said lip formation forming an obtuse angle with the surface of said bit body outwardly of said lip formation.
Claim 26
Dependent Claim
39 words
A bit according to claim 21 wherein said elongate body has an indexing formation of limited circumferential extent, and said lip formation extends around the entire circumference of said elongate body except in the area of said indexing formation.
Claim 27
Dependent Claim
30 words
A bit according to claim 22 wherein said bit body has, associated with each of said bores, an indexing formation sealingly engaging the indexing formation of the respective elongate body.
Claim 28
Dependent Claim
16 words
A bit according to claim 23 wherein said bit body comprises a tungsten carbide matrix material.
Claim 29
Dependent Claim
27 words
A bit according to claim 24 wherein the operating portion of each of said elongate bodies carries a layer of superhard material defining a concave cutting face.
Claim 30
Dependent Claim
33 words
A bit according to claim 21 wherein said operating portions of said elongated bodies have cutting faces having back rake angles which become less and less negative with distance from said bit body.
Claim 31
Dependent Claim
35 words
A bit according to claim 26 wherein each of said cutting members further comprises a layer of superhard material carried by said operating portion and defining said cutting face, said cutting face being concave outwardly.
Claim 32
Dependent Claim
31 words
A bit according to claim 21 wherein the outer surface of said bit body has a respective counterbore about each of said bores receiving the respective one of said lip formations.
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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) | 1988-09-02 | 1989-03-04 | 1989-09-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-02 | 1993-03-04 | 1993-09-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-02 | 1997-03-04 | 1997-09-03 | $7700.00 | Window Closed / Lapsed |