US3735825A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pressure equalizing system for rock bits
Assignee: Dresser Industries Inc
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Filing: 1972-03-07
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Granted: 1973-05-29
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Expires: 1992-03-07
Abstract
Abstract A lubricant reservoir is positioned in each arm of a three cone rotary rock bit to provide lubricant to bearings located between the bit''s rotary cone cutters and the bearing shafts upon which the cutters rotate. A seal is positioned between the cutters and the bearing shafts to retain lubricant in the bearing area and to prevent borehole fluids and debris from entering the bearing area. A pressure equalizing passage provides communication between the lubricant reservoir and the outside of the bit. A two-way valve is positioned in the pressure equalizing passage to prevent excessive pressure differentials from building up between lubricant in the lubricant reservoir and fluid outside of the bit by allowing lubricant from the lubricant reservoir to escape to the outside of the bit and allowing fluid outside of the bit to enter the lubricant reservoir.
Inventors
- 👤 W S Arlington Keller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:00
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/08; E21B10/22; E21B10/24
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
120 words
A sealed bearing rotary rock bit for drilling in a fluid filled borehole, comprising: a bit body; at least one bearing shaft extending from said bit body; a cutter rotatably mounted upon said bearing shaft; bearing means between said cutter and said bearing shaft for promoting rotation of said cutter; a lubricant reservoir in said bit body, said lubricant reservoir communicatIng with said bearing means; a pressure equalizing passage means in said bit body for providing fluid communication between the lubricant reservoir and the fluid filled borehole; and a two-way valve means in said fluid passage for allowing lubricant in said lubricant reservoir to escape into the borehole and for allowing fluid in the borehole to enter said lubricant reservoir.
Claim 2
Dependent Claim
120 words
A sealed bearing rotary rock bit for drilling in a fluid filled borehole, comprising: a bit body; at least one bearing shaft extending from said bit body; a cutter rotatably mounted upon said bearing shaft; bearing means between said cutter and said bearing shaft for promoting rotation of said cutter; a lubricant reservoir in said bit body, said lubricant reservoir communicatIng with said bearing means; a pressure equalizing passage means in said bit body for providing fluid communication between the lubricant reservoir and the fluid filled borehole; and a two-way valve means in said fluid passage for allowing lubricant in said lubricant reservoir to escape into the borehole and for allowing fluid in the borehole to enter said lubricant reservoir.
Claim 3
Dependent Claim
77 words
The sealed bearing rotary rock bit of claim 1 including a flexible diaphragm in said lubricant reservoir dividing said lubricant reservoir into a lubricant portion and a pressure equalizing portion and a passage in said bit body to provide fluid communication between said pressure equalizing portion of said lubricant reservoir and said fluid filled borehole with said pressure equalizing passage means providing fluid communication between the lubricant portion of said lubricant reservoir and the fluid filled borehole.
Claim 4
Dependent Claim
114 words
A rock bit comprising: a bit body; at least one arm extending from said body; a cone cutter mounted upon said arm; bearing means between said cone cutter and said arm for promoting rotation of said cutter; a seal between said cone cutter and said arm; a lubricant reservoir in said arm; a lubricant passage extending from said lubricant reservoir to said bearing means; a pressure equalizing passage in said arm, said pressure equalizing passage communicating said lubricant reservoir with the outside of the bit; and valve means in said pressure equalizing passage for allowing lubricant to escape from said lubricant reservoir and for allowing fluid to enter said lubricant reservoir thereby equalizing pressures.
Claim 5
Dependent Claim
114 words
A rock bit comprising: a bit body; at least one arm extending from said body; a cone cutter mounted upon said arm; bearing means between said cone cutter and said arm for promoting rotation of said cutter; a seal between said cone cutter and said arm; a lubricant reservoir in said arm; a lubricant passage extending from said lubricant reservoir to said bearing means; a pressure equalizing passage in said arm, said pressure equalizing passage communicating said lubricant reservoir with the outside of the bit; and valve means in said pressure equalizing passage for allowing lubricant to escape from said lubricant reservoir and for allowing fluid to enter said lubricant reservoir thereby equalizing pressures.
Claim 6
Dependent Claim
68 words
The rock bit of claim 3 including a flexible diaphragm in said lubricant reservoir dividing said lubricant reservoir into a lubricant portion and a pressure equalizing portion and a vent passage in said arm connecting said pressure equalizing portion of said lubricant reservoir with the outside of the bit with said pressure equalizing passage communicating the lubricant portion of said lubricant reservoir with the outside of the bit.
Claim 7
Dependent Claim
147 words
A rotary rock bit for drilling in a fluid filled borehole, comprising: a main bit body, said main bit body including three individual arms; a rotatable cutter mounted upon each of said arms; bearing means between each of said cutters and said arms; a seal between each of said cutters and said arms; a reservoir in each of said arms, each of said reservoirs containing lubricant; a lubricant passage in each of said arms, each lubricant passage extending from a reservoir to a respective bearing means; a pressure equalizing passage means in each of said arms for communicating each of said reservoirs with the area outside the bit; and two-way valve means in each of said pressure equalizing passage means for allowing lubricant in the lubricant reservoir to escape into the borehole and for allowing fluid in the borehole to enter said lubricant reservoir thereby equalizing pressures.
Claim 8
Dependent Claim
147 words
A rotary rock bit for drilling in a fluid filled borehole, comprising: a main bit body, said main bit body including three individual arms; a rotatable cutter mounted upon each of said arms; bearing means between each of said cutters and said arms; a seal between each of said cutters and said arms; a reservoir in each of said arms, each of said reservoirs containing lubricant; a lubricant passage in each of said arms, each lubricant passage extending from a reservoir to a respective bearing means; a pressure equalizing passage means in each of said arms for communicating each of said reservoirs with the area outside the bit; and two-way valve means in each of said pressure equalizing passage means for allowing lubricant in the lubricant reservoir to escape into the borehole and for allowing fluid in the borehole to enter said lubricant reservoir thereby equalizing pressures.
Claim 9
Dependent Claim
74 words
The rotary rock bit of claim 5 including a flexible diaphragm in each of said reservoirs dividing said reservoirs into a lubricant portion and a pressure equalizing portion and a vent passage in each of said arms connecting a respective pressure equalizing portion of a reservoir with the area outside of the bit, with said pressure equalizing passage means communicating the lubricant portion of a respective reservoir with the area outside of the bit.
Claim 10
Dependent Claim
127 words
In a rock bit that includes a bit body, at least one arm extending from said bit body, said arm terminating in a bearing shaft, a cone cutter rotatably mounted upon said bearing shaft, bearing means between said cone cutter and said bearing shaft for promoting rotation of said cone cutter upon said bearing shaft, and a seal positioned between the open end of said cone cutter and said bearing shaft; a pressure equalizing system, comprising: a lubricant reservoir in said arm, a lubricant passaGe communicating said lubricant reservoir with said bearing means, a pressure equalizing passage communicating said lubricant reservoir with the outside of the bit, and two-way valve means in said pressure equalizing passage for allowing fluid flow into and out of said lubricant reservoir.
Claim 11
Dependent Claim
127 words
In a rock bit that includes a bit body, at least one arm extending from said bit body, said arm terminating in a bearing shaft, a cone cutter rotatably mounted upon said bearing shaft, bearing means between said cone cutter and said bearing shaft for promoting rotation of said cone cutter upon said bearing shaft, and a seal positioned between the open end of said cone cutter and said bearing shaft; a pressure equalizing system, comprising: a lubricant reservoir in said arm, a lubricant passaGe communicating said lubricant reservoir with said bearing means, a pressure equalizing passage communicating said lubricant reservoir with the outside of the bit, and two-way valve means in said pressure equalizing passage for allowing fluid flow into and out of said lubricant reservoir.
Claim 12
Dependent Claim
64 words
The rock bit of claim 7 including a flexible diaphragm in said reservoir dividing said reservoir into a lubricant portion and a pressure equalizing portion and a vent passage communicating said pressure equalizing portion of said lubricant reservoir with the outside of the bit and wherein said pressure equalizing passage communicates said lubricant portion of said lubricant reservoir with the outside of the bit.
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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) | 1976-05-28 | 1976-11-27 | 1977-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-28 | 1980-11-27 | 1981-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-28 | 1984-11-27 | 1985-05-29 | $7700.00 | Window Closed / Lapsed |