US4145094A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rotary rock bit and method of making same
Assignee: Smith International Inc
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Filing: 1977-11-09
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Granted: 1979-03-20
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Expires: 1997-11-09
Abstract
Abstract A rotary rock bit is described having a plurality of legs extending downwardly from the main bit body. Each leg includes an annular bore extending through the lower extremity thereof. A separate journal pin is provided for each leg, with each journal pin having a mounting end and a bearing end. The mounting end of each journal pin is adapted to extend into the bore of a respective leg and be secured thereto by an electron beam welding process. The bearing end of the journal pin is adapted to receive an annular thrust member extending over the bearing surface thereof. The annular thrust member is secured to the journal pin by the same electron beam welding process step which welds the journal pin to the bore of the leg. A cone type cutter is adapted to be rotatably mounted on the bearing end of each journal pin with the annular thrust member functioning to retain the cutter on the journal pin and to absorb the in and out-thrust and radial loads passing therethrough.
Inventors
- 👤 Edward Vezirian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 11:02
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/08; E21B10/20; E21B10/22; F; F16; F16C; F16C2352/00
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
136 words
A rotary rock bit having a main bit body with at least one leg extending downwardly therefrom, each leg comprising: a bore extending through the lower extremity of said leg; a journal pin having a mounting end extending into said bore and a bearing end; a cutter rotatably supported on the bearing end of said journal pin; annular means located about the bearing end of said journal pin for axially retaining said cutter on said journal pin, said annular retaining means comprising a hollow cylindrical thrust member, the interior of which extends around the bearing end of said journal pin; and weld means extending along the mounting and bearing ends of said journal pin for securing said journal pin to the bore of said leg and for securing the annular retaining means to said journal pin.
Claim 2
Dependent Claim
136 words
A rotary rock bit having a main bit body with at least one leg extending downwardly therefrom, each leg comprising: a bore extending through the lower extremity of said leg; a journal pin having a mounting end extending into said bore and a bearing end; a cutter rotatably supported on the bearing end of said journal pin; annular means located about the bearing end of said journal pin for axially retaining said cutter on said journal pin, said annular retaining means comprising a hollow cylindrical thrust member, the interior of which extends around the bearing end of said journal pin; and weld means extending along the mounting and bearing ends of said journal pin for securing said journal pin to the bore of said leg and for securing the annular retaining means to said journal pin.
Claim 3
Dependent Claim
29 words
The combination of claim 1 wherein said cylindrical thrust member includes at least one surface which engages a bearing surface of said cutter for transferring a bearing load therethrough.
Claim 4
Dependent Claim
17 words
The combination of claim 2 wherein said cutter includes an internal groove partially receiving said thrust member.
Claim 5
Dependent Claim
21 words
The combination of claim 2 wherein said thrust member includes an end surface for engaging a bearing surface of said cutter.
Claim 6
Dependent Claim
21 words
The combination of claim 4 wherein said thrust face end surface is substantially parallel to the outer surface of said cutter.
Claim 7
Dependent Claim
24 words
The combination of claim 1 wherein said thrust member comprises a plurality of arcuate sections extending around the bearing end of said journal pin.
Claim 8
Dependent Claim
18 words
The combination of claim 1 wherein the mounting and bearing ends of said journal pin have cylindrical surfaces.
Claim 9
Dependent Claim
27 words
The combination of claim 7 wherein said leg bore includes a cylindrical interior surface for receiving and engaging the cylindrical surface of said journal pin mounting surface.
Claim 10
Dependent Claim
28 words
The combination of claim 7 wherein the cylindrical surfaces of the mounting and bearing ends of said journal pin are coextensive, with each surface having the same radius.
Claim 11
Dependent Claim
124 words
A rotary rock bit having a main bit body with at least one leg extending downwardly therefrom, each leg comprising: a cylindrical bore extending through the lower extremity thereof; a cylindrical journal pin having a mounting surface extending into and engaging the cylindrical bore of said leg and a bearing surface; a cutter rotatably supported on said journal pin; an annular thrust member extending completely around and engaging the cylindrical bearing surface of said journal pin; means for axially retaining said cutter to said thrust member; and a weld fusing the cylindrical mounting surface of said journal pin to the cylindrical bore of said leg and fusing the engaging surface of said annular thrust member to the cylindrical bearing surface of said journal pin.
Claim 12
Dependent Claim
124 words
A rotary rock bit having a main bit body with at least one leg extending downwardly therefrom, each leg comprising: a cylindrical bore extending through the lower extremity thereof; a cylindrical journal pin having a mounting surface extending into and engaging the cylindrical bore of said leg and a bearing surface; a cutter rotatably supported on said journal pin; an annular thrust member extending completely around and engaging the cylindrical bearing surface of said journal pin; means for axially retaining said cutter to said thrust member; and a weld fusing the cylindrical mounting surface of said journal pin to the cylindrical bore of said leg and fusing the engaging surface of said annular thrust member to the cylindrical bearing surface of said journal pin.
Claim 13
Dependent Claim
23 words
The combination of claim 10 wherein the mounting surface and the bearing surface of said journal pin lie in the same cylindrical plane.
Claim 14
Dependent Claim
19 words
The combination of claim 11 wherein the weld extends axially equidistant around the cylindrical surface of said journal pin.
Claim 15
Dependent Claim
39 words
The combination of claim 11 wherein the common axis of the cylindrical bore of said leg and the cylindrical surface of said journal pin is at an acute angle with respect to the axis of the main bit body.
Claim 16
Dependent Claim
32 words
The combination of claim 13 wherein the cylindrical bore of said leg further includes a larger counter bore located on the outer side thereof with respect to the main bit body axis.
Claim 17
Dependent Claim
44 words
The combination of claim 14 further including a plug element having a cylindrical surface extending into and engaging the cylindrical surface of said counterbore and an end surface for abutting the end of said journal pin extending away from the main bit body axis.
Claim 18
Dependent Claim
27 words
The combination of claim 15 further including a weld fusing a portion of the cylindrical surface of said plug element to the cylindrical surface of said counterbore.
Claim 19
Dependent Claim
22 words
The combination of claim 10 wherein said retaining means includes an internal groove formed in said cutter partially receiving said thrust member.
Claim 20
Dependent Claim
15 words
The combination of claim 10 wherein said thrust member comprises at least two arcuate sections.
Claim 21
Dependent Claim
172 words
Method of manufacturing a rotary rock bit comprising the steps of: providing a main bit body having at least one leg extending downwardly therefrom; boring a cylindrical bore through the lower extremity of the leg; providing a journal pin having a cylindrical mounting end and a cylindrical bearing end; inserting the cylindrical mounting end of said journal pin into the cylindrical bore of the leg; providing a cutter having an undercut cavity formed therein; providing an annular thrust member having a cylindrical surface adapted to extend around the cylindrical bearing end of the journal pin; inserting said thrust member within the undercut cavity of said cutter to be axially retained therein; inserting said journal pin into the thrust member; and continuously welding along the cylindrical mounting and bearing ends of said journal pin for fusing the cylindrical surface of said journal pin mounting end to the cylindrical surface of said leg bore and for fusing the cylindrical surface to the annular thrust member to the cylindrical bearing end of said journal pin.
Claim 22
Dependent Claim
172 words
Method of manufacturing a rotary rock bit comprising the steps of: providing a main bit body having at least one leg extending downwardly therefrom; boring a cylindrical bore through the lower extremity of the leg; providing a journal pin having a cylindrical mounting end and a cylindrical bearing end; inserting the cylindrical mounting end of said journal pin into the cylindrical bore of the leg; providing a cutter having an undercut cavity formed therein; providing an annular thrust member having a cylindrical surface adapted to extend around the cylindrical bearing end of the journal pin; inserting said thrust member within the undercut cavity of said cutter to be axially retained therein; inserting said journal pin into the thrust member; and continuously welding along the cylindrical mounting and bearing ends of said journal pin for fusing the cylindrical surface of said journal pin mounting end to the cylindrical surface of said leg bore and for fusing the cylindrical surface to the annular thrust member to the cylindrical bearing end of said journal pin.
Claim 23
Dependent Claim
15 words
The method of claim 19 wherein the welding step utilizes an electron beam welding process.
Claim 24
Dependent Claim
114 words
A rotary rock bit having a main bit body with at least one leg extending downwardly therefrom, each leg comprising: a bore extending through the lower extremity of said leg; a journal pin having a mounting end extending into said bore and a bearing end; a cutter rotatably supported on the bearing end of said journal pin; annular means located about the bearing end of said journal pin for axially retaining said cutter on said journal pin; and continuous weld means extending along the mounting and bearing ends of said journal pin for securing said journal pin to the bore of said leg and for securing the annular retaining means to said journal pin.
Claim 25
Dependent Claim
114 words
A rotary rock bit having a main bit body with at least one leg extending downwardly therefrom, each leg comprising: a bore extending through the lower extremity of said leg; a journal pin having a mounting end extending into said bore and a bearing end; a cutter rotatably supported on the bearing end of said journal pin; annular means located about the bearing end of said journal pin for axially retaining said cutter on said journal pin; and continuous weld means extending along the mounting and bearing ends of said journal pin for securing said journal pin to the bore of said leg and for securing the annular retaining means to said journal pin.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-03-19 | 1982-09-18 | 1983-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-03-19 | 1986-09-18 | 1987-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-03-19 | 1990-09-18 | 1991-03-20 | $7700.00 | Window Closed / Lapsed |