Patent US3842602A successfully refreshed from Google Patents.
US3842602A
Expired / Lapsed
US
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Miner tram control circuit
Assignee: Joy Manufacturing Co
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Filing: 1973-07-09
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Granted: 1974-10-22
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Expires: 1993-07-09
Abstract
Abstract A fluid control circuit for use in a mining machine tram system whereby there is provided a protection control to prevent undesired movement of a mining machine and a selective range of speed controls as may be required under different operating conditions. A plurality of interlocked valve mechanisms are utilized with a means of limiting operation of certain valves when control of a slow speed range is desired.
Inventors
- 👤 G Daily
- 👤 D Ziegler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:36
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/38; F16H61/40; F16H61/46; F16H61/47; F16H61/42
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
138 words
A method of controlling the tramming rate of a mining machine having a constant speed hydraulic pump means and at least one hydraulic driving motor for tramming comprising the steps of: directing at least a major portion of the output of pressurized hydraulic fluid from said pump means to said driving motor for hydraulic energization thereof; directing a first control portion of such pressurized hydraulic fluid from said pump means to a first control valve means; selectively moving said first control valve means to vary the quantity of output of pressurized hydraulic fluid from said pump means; directing a second control portion of such pressurized fluid from said pump means to a second control valve means; selectively moving said second control valve means to limit the maximum quantity of output of pressurized hydraulic fluid from said pump means.
Claim 2
Independent Claim
138 words
A method of controlling the tramming rate of a mining machine having a constant speed hydraulic pump means and at least one hydraulic driving motor for tramming comprising the steps of: directing at least a major portion of the output of pressurized hydraulic fluid from said pump means to said driving motor for hydraulic energization thereof; directing a first control portion of such pressurized hydraulic fluid from said pump means to a first control valve means; selectively moving said first control valve means to vary the quantity of output of pressurized hydraulic fluid from said pump means; directing a second control portion of such pressurized fluid from said pump means to a second control valve means; selectively moving said second control valve means to limit the maximum quantity of output of pressurized hydraulic fluid from said pump means.
Claim 3
Dependent Claim
37 words
The method as specified in claim 1 wherein said pump means includes a charge pump portion and said first and second control portions of pressurized hydraulic fluid are directed from the output of said charge pump portion.
Claim 4
Dependent Claim
39 words
A method as specified in claim 1 wherein said second control portion selectively limits the quantity of said output from said pump means between a first maximum output and a second maximum output less than said first maximum output.
Claim 5
Dependent Claim
29 words
A method as specified in claim 3 wherein during said first maximum output said directing of said second control portion of said pressurized hydraulic fluid is to a reservoir.
Claim 6
Dependent Claim
48 words
A method as specified in claim 3 wherein during said second maximum output said directing of said second control portion of said pressurized hydraulic fluid cooperates with said first control portion to limit said output of pressurized hydraulic fluid from said pump means to said second maximum output.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-21 | 1978-04-22 | 1978-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-21 | 1982-04-22 | 1982-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-21 | 1986-04-22 | 1986-10-22 | $7700.00 | Window Closed / Lapsed |