US3685601A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Drill bit
Assignee: GW Murphy Industries Inc
•
Filing: 1971-03-01
•
Granted: 1972-08-22
•
Expires: 1991-03-01
Abstract
Abstract A rotary drill bit having a plurality of journal-mounted rotating cutters, jet passageways through which drilling fluid is discharged between the cutters and check valves disposed in the passageways to permit drilling fluid to flow therethrough to the cutters and to prevent flow in reverse direction therethrough into the interior of the bit.
Inventors
- 👤 Frank A Hollingshead
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 17:43
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/08; E21B10/18; E21B10/22; E21B10/23; E21B21/00; E21B21/10
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
53 words
A rotary drill bit, comprising a body, a plurality of rotary cutters, means for rotatively mounting said cutters on said body, said body defining a plurality of passageways, and means in each of said passageways for directing flow outward from said bit between said cutters and for preventing reverse flow through said passageways.
Claim 2
Dependent Claim
53 words
A rotary drill bit, comprising a body, a plurality of rotary cutters, means for rotatively mounting said cutters on said body, said body defining a plurality of passageways, and means in each of said passageways for directing flow outward from said bit between said cutters and for preventing reverse flow through said passageways.
Claim 3
Dependent Claim
50 words
The rotary bit of claim 1, wherein each of said flow control means is removable from and insertable into said passageway or passageways from the exterior of said bit body adjacent to said cutter or cutters and including means for releasably securing each of said control means in said passageway.
Claim 4
Dependent Claim
42 words
The rotary bit of claim 2, wherein each of said flow control means includes a check valve nozzle removably secured in each of said passageways and operable to permit fluid to flow through each of said passageways out of said bit body.
Claim 5
Dependent Claim
32 words
The rotary bit of claim 3 wherein each of said check valve nozzles includes a pivoting plate adapted to close said passageway, and a spring urging said plate toward its closed position.
Claim 6
Dependent Claim
25 words
The rotary bit of claim 4 wherein said releasable means a set screw to removably secure each of said check valve nozzles in its passageway.
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) | 1975-08-22 | 1976-02-21 | 1976-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-22 | 1980-02-21 | 1980-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-22 | 1984-02-21 | 1984-08-22 | $7700.00 | Window Closed / Lapsed |