US3946820A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Novel cutter elements for drill bits
Assignee: Individual
•
Filing: 1974-10-25
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Granted: 1976-03-30
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Expires: 1994-10-25
Abstract
Abstract Improved cutter elements for drill bits of the type having two to four conical-shaped cutters mounted in a supporting body for rotation about their respective axes with their apices inclined downwardly-inwardly toward the axis of rotation of the body; the cutter elements are spaced apart from one another both axially and circumferentially of the substantially conical exterior of each conical-shaped cutter and, usually, disposed in spaced circumferential rows, each cutter element including a pair of interacting chisel or wedge-shaped teeth intersecting each other--preferably at their medial portions in perpendicular relationship--coextensive from crest to root and having their respective crests extending approximately radially of the axis of rotation of said cutter and generally circumferentially of said cutter axis; the circumferentially--oriented teeth have coextensive cutting edges at their ends and are adapted to cut through ridges created in the formation by the radially-oriented teeth and laterally displace cuttings of the latter as well as contact said formation ahead or prior thereto so as to permit greater penetration of said radially-oriented teeth. Both teeth of each cutter element may be of relatively narrow transverse dimensions or thickness as well as minimum taper, such as 40° or less, and the circumferential spacing between adjacent cutter elements may be relatively wide without unduly weakening said teeth, whereby a drill bit having such cutter elements may be utilized in varying formations, from relatively soft to relatively hard, so as to minimize the necessity of replacing the bit before exhaustion of its usefulness.
Inventors
- 👤 Seth Raymond Knapp
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:13
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/08; E21B10/16
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
346 words
In an earth boring drill bit having at least one bearing means projecting downwardly-inwardly from the peripheral portion of its hollow body and a conical-shaped rotary cutter journaled on the bearing means with its large end outermost from the axis of the drill bit, the improvement which comprises a plurality of discrete cutter elements on the substantially conical exterior of the conical-shaped rotary cutter and spaced apart from one another both axially and circumferentially thereof, each of at least some of the cutter elements having a quandrangular base and including a pair of chisel-shaped teeth having crests at the outer extremity of and oriented diagonally of each of said cutter elements and intersecting at their medial portions, one of the chisel-shaped diagonally-oriented teeth of each of said quadrangular cutter elements having its crest extending generally radially of the axis of rotation of said conical-shaped rotary cutter, the other chisel-shaped diagonally-oriented tooth of each of said quadrangular cutter elements having its crest extending generally circumferentially of said cutter exterior, said teeth being coextensive from crest to root of each other and from the outer extremity to the base of each of said quadrangular cutter elements, whereby said teeth reinforce each other so as to permit minimum taper thereof and consequent faster penetration without the use of excessive weight and whereby circumferential spacing between said cutter elements may be relatively wide without unduly weakening said teeth, each of the circumferentially-oriented teeth having a linear longitudinal coextensive cutting edge at least at its leading end extending from its crest to its root at the base of its cutter element due to the orientation of said teeth diagonally of their respective cutter elements, the leading end of each of said circumferentially-oriented teeth having a coextensive face on each side of its longitudinal cutting edge with each face disposed in angular relation to the other and decreasing in width from said base to said outer extremity of its cutter element so as to reduce the thickness of the leading end crest portion of said tooth and thereby increase its penetration capability.
Claim 2
Dependent Claim
346 words
In an earth boring drill bit having at least one bearing means projecting downwardly-inwardly from the peripheral portion of its hollow body and a conical-shaped rotary cutter journaled on the bearing means with its large end outermost from the axis of the drill bit, the improvement which comprises a plurality of discrete cutter elements on the substantially conical exterior of the conical-shaped rotary cutter and spaced apart from one another both axially and circumferentially thereof, each of at least some of the cutter elements having a quandrangular base and including a pair of chisel-shaped teeth having crests at the outer extremity of and oriented diagonally of each of said cutter elements and intersecting at their medial portions, one of the chisel-shaped diagonally-oriented teeth of each of said quadrangular cutter elements having its crest extending generally radially of the axis of rotation of said conical-shaped rotary cutter, the other chisel-shaped diagonally-oriented tooth of each of said quadrangular cutter elements having its crest extending generally circumferentially of said cutter exterior, said teeth being coextensive from crest to root of each other and from the outer extremity to the base of each of said quadrangular cutter elements, whereby said teeth reinforce each other so as to permit minimum taper thereof and consequent faster penetration without the use of excessive weight and whereby circumferential spacing between said cutter elements may be relatively wide without unduly weakening said teeth, each of the circumferentially-oriented teeth having a linear longitudinal coextensive cutting edge at least at its leading end extending from its crest to its root at the base of its cutter element due to the orientation of said teeth diagonally of their respective cutter elements, the leading end of each of said circumferentially-oriented teeth having a coextensive face on each side of its longitudinal cutting edge with each face disposed in angular relation to the other and decreasing in width from said base to said outer extremity of its cutter element so as to reduce the thickness of the leading end crest portion of said tooth and thereby increase its penetration capability.
Claim 3
Dependent Claim
19 words
The improvement defined in claim 1 wherein at least some of the quadrangular cutter elements are equilateral in plan.
Claim 4
Dependent Claim
19 words
The improvement defined in claim 1 wherein at least some of the quadrangular cutter elements are parallelogrammatical in plan.
Claim 5
Dependent Claim
19 words
The improvement defined in claim 1 wherein at least some of the quadrangular cutter elements are rectangular in plan.
Claim 6
Dependent Claim
19 words
The improvement defined in claim 1 wherein at least some of the quadrangular cutter elements are diamond-shaped in plan.
Claim 7
Dependent Claim
30 words
The improvement defined in claim 1 wherein the angular relation between the faces at the leading ends of at least some of the circumferentially-oriented teeth is not more than 90°.
Claim 8
Dependent Claim
20 words
The improvement defined in claim 1 wherein the leading faces of at least some of the circumferentially-oriented teeth are equilateral.
Claim 9
Dependent Claim
68 words
The improvement defined in claim 1 wherein each of at least some of the circumferentially-oriented teeth has a pair of opposed lateral flanks tapering from the base to the outer extremity of its cutter element and terminating at the crest of said tooth in a coextensive linear cutting edge. the leading margins of the opposed flanks forming the trailing margins of the leading faces of said circumferential teeth.
Claim 10
Dependent Claim
76 words
The improvement defined in claim 1 wherein the circumferential-oriented teeth of at least some of the quadrangular cutting elements have coextensive linear longitudinal cutting edges at both ends and a pair of coextensive faces, one on each side of each longitudinal cutting edge at each end of each tooth in angular relation to the other face of each pair and decreasing in width from the base to the outer extremity of each of said cutter elements.
Claim 11
Dependent Claim
28 words
The improvement defined in claim 1 wherein the circumferentially-oriented teeth of at least some of the quadrangular cutter elements have coextensive linear longitudinal cutting edges at both ends.
Claim 12
Dependent Claim
49 words
The improvement defined in claim 10 wherein each of at least some of the circumferential teeth has a pair of opposed lateral flanks tapering from the base to the outer extremity of its cutter element and terminating at the crest of said tooth in a coextensive linear cutting edge.
Claim 13
Dependent Claim
37 words
The improvement defined in claim 1 wherein the radially-oriented teeth as well as said circumferentially-oriented teeth of at least some of the quadrangular cutter elements have coextensive linear longitudinal cutting edges and coextensive faces at both ends.
Claim 14
Dependent Claim
66 words
The improvement defined in claim 12 wherein both teeth of at least some of the quadrangular cutting elements have a pair of coextensive faces, one on each side of each longitudinal cutting edge at each end of each tooth in angular relation to the other face of each pair and decreasing in width from the base to the outer extremity of each of said cutter elements.
Claim 15
Dependent Claim
226 words
In an earth boring drill bit having a plurality of conical-shaped rotary cutters carrying a plurality of discrete cutter elements, the improvement comprising at least some of the cutter elements of the rotary cutters being quadrilateral in plan, each of said quadrilateral cutter elements including a pair of chisel-shaped teeth coextensive from crest to root and from the outer extremity to the base of said element, the teeth being oriented diagonally of each quadrilateral cutter element whereby the crests of said teeth extend between opposed corners of said element and intersect at their medial portions. the crest of one of said teeth being directed radially of the axis of rotation of each rotary cutter, the crest of the other tooth being directed circumferentially of the exterior of said rotary cutter whereby said tooth and its crest have leading and trailing ends at opposed corners of said quadrilateral cutter elements, a coextensive cutting edge at the leading end of each circumferential tooth coinciding with the longitudinal edge of the leading corner of said quadrilateral cutter element and extending from the crest to the root of said tooth, the leading corner of said circumferential tooth having a pair of surfaces receding from and coextensive with the longitudinal cutting edge thereof, the pair of surfaces extending outwardly and rearwardly to points medially of said cutter element at its base.
Claim 16
Dependent Claim
226 words
In an earth boring drill bit having a plurality of conical-shaped rotary cutters carrying a plurality of discrete cutter elements, the improvement comprising at least some of the cutter elements of the rotary cutters being quadrilateral in plan, each of said quadrilateral cutter elements including a pair of chisel-shaped teeth coextensive from crest to root and from the outer extremity to the base of said element, the teeth being oriented diagonally of each quadrilateral cutter element whereby the crests of said teeth extend between opposed corners of said element and intersect at their medial portions. the crest of one of said teeth being directed radially of the axis of rotation of each rotary cutter, the crest of the other tooth being directed circumferentially of the exterior of said rotary cutter whereby said tooth and its crest have leading and trailing ends at opposed corners of said quadrilateral cutter elements, a coextensive cutting edge at the leading end of each circumferential tooth coinciding with the longitudinal edge of the leading corner of said quadrilateral cutter element and extending from the crest to the root of said tooth, the leading corner of said circumferential tooth having a pair of surfaces receding from and coextensive with the longitudinal cutting edge thereof, the pair of surfaces extending outwardly and rearwardly to points medially of said cutter element at its base.
Claim 17
Dependent Claim
19 words
The improvement defined in claim 14 wherein at least some of said quadrilateral cutter elements are rectangular in plan.
Claim 18
Dependent Claim
19 words
The improvement defined in claim 14 wherein at least some of said quadrilateral cutter elements are diamond-shaped in plan.
Claim 19
Dependent Claim
28 words
The improvement defined in claim 14 wherein the pair of surfaces of the leading corner of at least some of said quadrilateral cutter elements are equilateral in plan.
Claim 20
Dependent Claim
55 words
The improvement defined in claim 14 wherein at least some of said circumferential teeth have coextensive cutting edges at both their leading and trailing ends and opposed corners of the quadrilateral cutter elements as well as a pair of surfaces receding from each of said cutting edges toward the other opposed corners of said elements.
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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) | 1979-03-30 | 1979-09-29 | 1980-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-30 | 1983-09-29 | 1984-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-30 | 1987-09-29 | 1988-03-30 | $7700.00 | Window Closed / Lapsed |