US3765495A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Drill bit seals
Assignee: G W MURPHEY IND Inc
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Filing: 1972-08-02
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Granted: 1973-10-16
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Expires: 1992-08-02
Abstract
Abstract An earth boring drill employing roller cutters is provided with a new and improved seal to inhibit ingress of detritus into the cutter bearing area and egress of lubricant therefrom. The parts may be so arranged that when assembled, the seal is placed in hoop compression. The shape of the seal is such that its cross section is not overly compressed or displaced when in operating position: this prevents undue compression set, wear and heating of the seal. Also, the seal has a greater radial cross-sectional extent that axial extent by a ratio of at least one-and-one-half to one to conserve bearing space and to provide the necessary flexibility to accommodate the various movements of the cutter relative to the shaft upon which it is rotatably mounted.
Inventors
- 👤 H Murdoch
- 👤 P Schumacher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 15:41
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/08; E21B10/22; E21B10/25; F; F16; F16J; F16J15/00; F16J15/16; F16J15/32
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
98 words
Seal means for use in an earth boring drill bit having a head, a bearing shaft arranged thereon and a cutter rotatably mounted on the bearing shaft, including: the cutter having a circumferential groove therein, an elastomeric seal ring in said groove, the seal ring, the groove and the bearing shaft area confronting the groovE being sized so that upon assembly of the cutter on the shaft the seal ring is compressed less than 10% of its relaxed condition radial thickness, the seal ring having a radial cross-sectional extent at least one and one-half times its axial extent.
Claim 2
Dependent Claim
98 words
Seal means for use in an earth boring drill bit having a head, a bearing shaft arranged thereon and a cutter rotatably mounted on the bearing shaft, including: the cutter having a circumferential groove therein, an elastomeric seal ring in said groove, the seal ring, the groove and the bearing shaft area confronting the groovE being sized so that upon assembly of the cutter on the shaft the seal ring is compressed less than 10% of its relaxed condition radial thickness, the seal ring having a radial cross-sectional extent at least one and one-half times its axial extent.
Claim 3
Dependent Claim
39 words
Seal means according to claim 1 wherein: the inside diameter of the sealing ring being larger than the diameter of the shaft when the seal ring is in its relaxed condition before being installed in the drill bit cutter.
Claim 4
Dependent Claim
26 words
Seal means according to claim 1 wherein: the elastomers at the inside diameter and at the outside diameter of the seal ring are in hoop compression.
Claim 5
Dependent Claim
17 words
Seal means according to claim 1 wherein: the seal ring is in hoop compression and radial compression.
Claim 6
Dependent Claim
21 words
Seal means according to claim 1 wherein: the elastomer at the inside diameter of the seal ring is in hoop compression.
Claim 7
Dependent Claim
14 words
Seal means according to claim 1 wherein: the seal ring rotates with said cutter.
Claim 8
Dependent Claim
82 words
Seal means for use in an earth boring drill bit having a head, a bearing shaft arranged thereon and a cutter rotatably mounted on the bearing shaft, including: the cutter having a circumferential groove therein, an elastomeric seal ring in said groove in sealing and sliding engagement with said shaft, the inside diameter of the sealing ring being larger than the diameter of the shaft when the seal ring is in its relaxed condition before being installed in the drill bit cutter.
Claim 9
Dependent Claim
82 words
Seal means for use in an earth boring drill bit having a head, a bearing shaft arranged thereon and a cutter rotatably mounted on the bearing shaft, including: the cutter having a circumferential groove therein, an elastomeric seal ring in said groove in sealing and sliding engagement with said shaft, the inside diameter of the sealing ring being larger than the diameter of the shaft when the seal ring is in its relaxed condition before being installed in the drill bit cutter.
Claim 10
Dependent Claim
29 words
Seal means according to claim 7 wherein: the inside diameter of the seal ring is smaller than the shaft diameter after the seal is installed in the cutter groove.
Claim 11
Dependent Claim
96 words
Seal means for use in an earth boring drill bit having a head, a bearing shaft arranged thereon and a cutter rotatably mounted on the bearing shaft including: the cutter having a circumferential groove therein, an elastomeric seal ring in said groove in sealing and sliding engagement with said shaft, the diametral clearance between the outside diameter of the shaft and the inside diameter of the seal ring in its relaxed condition before being installed in the cutter groove and on said shaft, is at least one percent of the inside diameter of the seal ring.
Claim 12
Dependent Claim
96 words
Seal means for use in an earth boring drill bit having a head, a bearing shaft arranged thereon and a cutter rotatably mounted on the bearing shaft including: the cutter having a circumferential groove therein, an elastomeric seal ring in said groove in sealing and sliding engagement with said shaft, the diametral clearance between the outside diameter of the shaft and the inside diameter of the seal ring in its relaxed condition before being installed in the cutter groove and on said shaft, is at least one percent of the inside diameter of the seal ring.
Claim 13
Dependent Claim
78 words
A drill bit comprising: at least one head, a bearing shaft arranged on said head, and a cutter rotatably mounted on said bearing shaft, said cutter having a circumferential groove therein, and an elastomeric seal ring in said groove in sealing and sliding engagement with said shaft, the inside diameter of said sealing ring being larger than the diameter of said shaft when said seal ring is in its relaxed condition prior to being installed in said cutter.
Claim 14
Dependent Claim
78 words
A drill bit comprising: at least one head, a bearing shaft arranged on said head, and a cutter rotatably mounted on said bearing shaft, said cutter having a circumferential groove therein, and an elastomeric seal ring in said groove in sealing and sliding engagement with said shaft, the inside diameter of said sealing ring being larger than the diameter of said shaft when said seal ring is in its relaxed condition prior to being installed in said cutter.
Claim 15
Dependent Claim
102 words
A drill bit comprising: at least one head, bearing shaft arranged on said head, and a cutter rotatably mounted on said bearing shaft, said cutter having circumferential groove therein, and an elastomeric seal ring in said groove in sealing and sliding engagement with said shaft, said seal ring, said groove, and said bearing shaft area confronting said groove being sized so that upon assembly of said cutter on said shaft, said seal ring is compressed less than 10 percent of its relaxed condition radial thickness, said seal ring having a radial cross-sectional extent at least one and one-half times its axial extent.
Claim 16
Dependent Claim
102 words
A drill bit comprising: at least one head, bearing shaft arranged on said head, and a cutter rotatably mounted on said bearing shaft, said cutter having circumferential groove therein, and an elastomeric seal ring in said groove in sealing and sliding engagement with said shaft, said seal ring, said groove, and said bearing shaft area confronting said groove being sized so that upon assembly of said cutter on said shaft, said seal ring is compressed less than 10 percent of its relaxed condition radial thickness, said seal ring having a radial cross-sectional extent at least one and one-half times its axial extent.
References Cited (Backward Citations)
US2814465A
Cited
US2676790A
Cited
US3047344A
Cited
US3397928A
Cited
US3467448A
Cited
US3656764A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-15 | 1977-04-16 | 1977-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-15 | 1981-04-16 | 1981-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-15 | 1985-04-16 | 1985-10-16 | $7700.00 | Window Closed / Lapsed |