US3944306A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rock bit bearing seal
Assignee: Smith International Inc
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Filing: 1974-12-16
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Granted: 1976-03-16
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Expires: 1994-12-16
Abstract
Abstract A bearing seal for a rock bit, including a non-elastic annular core member and inner and outer flexible sealing rings each securely bonded to the core member throughout substantially its entire circumference, the core member providing dimensional stability for the sealing rings and hence extending the useful life of the bearing seal despite the elevated temperature and pressure levels to which it is subjected.
Inventors
- 👤 William J. Neilson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 05:26
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/08; E21B10/22; E21B10/25; F; F16; F16C; F16C33/00; F16C33/72; F16J; F16J15/00; F16J15/16; F16J15/32; F16C2352/00
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
241 words
An earth boring tool comprising: a. a bit body having at least one journal leg thereon; b. a rotary cutter rotatably mounted upon said journal leg; said journal leg having surface portions providing the radially inward surface and the axially outward surface of a seal gland, said cutter having surfaces providing the radially outward surface and the axially inward surface of the seal gland; and c. an annular seal disposed within said seal gland, said annular seal including 1. an annular solid circumferentially continuous metallic core, 2. an inner sealing ring portion of flexible material having elastomeric characteristics and being bonded to the radially inward side of said metallic core throughout substantially the entire circumference thereof, said inner ring portion engaging said radially inward surface of the seal gland, and 3. an outer sealing ring portion of flexible material having elastomeric characteristics and being bonded to the radially outward surface of said metallic core throughout substantially the entire circumference thereof and engaging said radially outward surface of the seal gland; said inner and outer sealing ring portions being of substantially the same corss-sectional area and having substantially the same exposed surface in moving sealing engagement with respectively adjacent surface portions of the seal gland, said metallic core serving to maintain the dimensional stability of both said inner and said outer sealing ring portions despite high levels of temperature and pressure applied to both the interior and exterior sides of said seal.
Claim 2
Dependent Claim
241 words
An earth boring tool comprising: a. a bit body having at least one journal leg thereon; b. a rotary cutter rotatably mounted upon said journal leg; said journal leg having surface portions providing the radially inward surface and the axially outward surface of a seal gland, said cutter having surfaces providing the radially outward surface and the axially inward surface of the seal gland; and c. an annular seal disposed within said seal gland, said annular seal including 1. an annular solid circumferentially continuous metallic core, 2. an inner sealing ring portion of flexible material having elastomeric characteristics and being bonded to the radially inward side of said metallic core throughout substantially the entire circumference thereof, said inner ring portion engaging said radially inward surface of the seal gland, and 3. an outer sealing ring portion of flexible material having elastomeric characteristics and being bonded to the radially outward surface of said metallic core throughout substantially the entire circumference thereof and engaging said radially outward surface of the seal gland; said inner and outer sealing ring portions being of substantially the same corss-sectional area and having substantially the same exposed surface in moving sealing engagement with respectively adjacent surface portions of the seal gland, said metallic core serving to maintain the dimensional stability of both said inner and said outer sealing ring portions despite high levels of temperature and pressure applied to both the interior and exterior sides of said seal.
Claim 3
Dependent Claim
27 words
An earth boring tool as in claim 1 wherein the radial diameter of said seal is at least one and one half times the axial length thereof.
Claim 4
Dependent Claim
30 words
An earth boring tool as in claim 1 wherein the cross-sectional area of said metallic core is substantially equal to the cross-sectional area of each of said sealing ring portions.
Claim 5
Dependent Claim
36 words
An earth boring tool as in claim 3 wherein the axial length of each of said sealing ring portions is greater than the axial length of said metallic core, thereby preventing metal-to-metal contact with said core.
Claim 6
Dependent Claim
36 words
An earth boring tool as in claim 1 wherein the axial length of each of said sealing ring portions is greater than the axial length of said metallic core, thereby preventing metal-to-metal contact with said core.
Claim 7
Dependent Claim
20 words
An earth boring tool as in claim 1 wherein said sealing ring portions are integrally formed as a single member.
Claim 8
Dependent Claim
36 words
An earth boring tool as claimed in claim 1 wherein said metallic core is of rectangular cross-sectional configuration and each of said sealing ring portions has a cross-sectional configuration comprising the greater part of a circle.
Claim 9
Dependent Claim
41 words
An earth boring tool as in claim 1 wherein portions of the exterior of said metallic core are substantially exposed whereby drilling fluid surrounding said boring tool is adapted to contact said core to convey heat away from said annular seal.
Claim 10
Dependent Claim
36 words
An earth boring tool as claimed in claim 8 wherein said metallic core is of rectangular cross-sectional configuration and each of said sealing ring portions has a cross-sectional configuration comprising the greater part of a circle.
Claim 11
Dependent Claim
203 words
In a rock bit having a bit body with at least one journal leg, a seal between the journal leg and the rotary cutter, said seal comprising: an annular metallic core; inner and outer sealing ring portions of flexible material having elastomeric characteristics; said sealing ring portions being disposed in opposite sides of said core, said inner ring portion having an annular engagement surface for a corresponding portion of the journal leg and said outer ring portion having an annular engagement surface for a corresponding portion of the cutter; and each of said sealing ring portions being bonded to said core throughout substantially the entire circumference thereof, whereby said core maintains the dimensional stability of said sealing ring portions despite high levels of temperature and pressure to which said seal is subjected, said engagement surface for the journal leg having an initial diameter greater than the diameter of the corresponding portion of the journal leg and said engagement surface for the cutter having a diameter greater than the diameter of the corresponding portion of the cutter whereby to compress said sealing ring portions between the journal leg and the cutter and in a direction transverse to the circumferential center line of said core.
Claim 12
Dependent Claim
203 words
In a rock bit having a bit body with at least one journal leg, a seal between the journal leg and the rotary cutter, said seal comprising: an annular metallic core; inner and outer sealing ring portions of flexible material having elastomeric characteristics; said sealing ring portions being disposed in opposite sides of said core, said inner ring portion having an annular engagement surface for a corresponding portion of the journal leg and said outer ring portion having an annular engagement surface for a corresponding portion of the cutter; and each of said sealing ring portions being bonded to said core throughout substantially the entire circumference thereof, whereby said core maintains the dimensional stability of said sealing ring portions despite high levels of temperature and pressure to which said seal is subjected, said engagement surface for the journal leg having an initial diameter greater than the diameter of the corresponding portion of the journal leg and said engagement surface for the cutter having a diameter greater than the diameter of the corresponding portion of the cutter whereby to compress said sealing ring portions between the journal leg and the cutter and in a direction transverse to the circumferential center line of said core.
Claim 13
Dependent Claim
25 words
The rock bit of claim 10 wherein said core, said inner sealing ring portion, and said outer sealing ring portion lie in a common plane.
Claim 14
Dependent Claim
19 words
The rock bit of claim 11 wherein the radial diameter of said seal is greater than its axial length.
Claim 15
Dependent Claim
24 words
The rock bit of claim 11 wherein the radial diameter of said seal is at least one and one-half times the axial length thereof.
Claim 16
Dependent Claim
27 words
The rock bit of claim 10 wherein the cross-sectional area of said metallic core is substantially equal to the cross-sectional area of each of said sealing portions.
Claim 17
Dependent Claim
19 words
The rock bit of claim 10 wherein said two sealing ring portions are integrally formed as a single member.
Claim 18
Dependent Claim
36 words
The rock bit of claim 10 wherein each of said sealing ring portions extends outward in three directions from the surfaces of the associated sides of said metallic core, thereby protecting said core from metal-to-metal contact.
Claim 19
Dependent Claim
42 words
The rock bit of claim 16 wherein on the exterior side of said seal there is a gap between said sealing ring portions through which said metallic core is exposed to drilling fluid in the well bore, thereby cooling said seal portions.
Claim 20
Dependent Claim
24 words
The rock bit of claim 10 wherein said inner sealing ring portion is made of a different material than said outer sealing ring portions.
Claim 21
Dependent Claim
23 words
The rock bit of claim 18 wherein said inner sealing ring portion has a different hardness value than said outer sealing ring portion
Claim 22
Dependent Claim
19 words
The rock bit of claim 10 wherein said inner and outer sealing ring portions are of differing cross-sectional configurations.
Claim 23
Dependent Claim
41 words
The rock bit of claim 10 wherein on the exterior side of said seal there is a gap between said sealing ring portions through which said metallic core is exposed to drilling fluid in the well bore, thereby cooling said seal.
Claim 24
Dependent Claim
32 words
The rock bit of claim 21 wherein said metallic core has a U-shaped cross-sectional configuration, with the groove thereof lying on the exterior side of said seal in communication with said gap.
References Cited (Backward Citations)
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Cited
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Cited
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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) | 1979-03-16 | 1979-09-15 | 1980-03-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-16 | 1983-09-15 | 1984-03-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-16 | 1987-09-15 | 1988-03-16 | $7700.00 | Window Closed / Lapsed |