US3987624A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic drive control system
Assignee: Individual
•
Filing: 1975-06-23
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Granted: 1976-10-26
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Expires: 1995-06-23
Abstract
Abstract A hydraulic drive control system for driving a generator or alternator or the like at a constant RPM regardless of variations in the output load or the input load comprising a driven pump having a variable volume and variable pressure output connected in a closed system to a hydraulic motor which will maintain a constant RPM output, regardless of the RPM's of the driving means, which is coupled to the device to be driven. Connected between the pump and the motor is a volume control line having a volume control valve which insures that the volume of fluid to the hydraulic motor will be constant thus providing a constant line RPM output of the driving motor, and a pressure regulating line connected between said pump and said motor to regulate the pump pressure output to insure that the motor RPM is constant although the load on the motor may vary. The volume control valve regulates hydraulic fluid between the pump and motor regardless of the pressure and volume output of the pump.
Inventors
- 👤 George H. Cooke
- 👤 A. Edward Appleby
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:55
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/38; F16H61/40; F16H61/42; F16H61/433; F16H61/46; F16H61/47
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
84 words
A variable input constant RPM output hydraulic drive control system comprising: a variable hydraulic displacement pump; a pump discharge means; volume control means connected to said discharge means; a constant displacement hydraulic motor; volume control input means connecting said volume control means to the input side of said motor; a motor discharge line connecting said motor and said pump input side; and a pressure sensing means connected to said pump discharge line and said motor input line for varying the displacement of said pump.
Claim 2
Dependent Claim
84 words
A variable input constant RPM output hydraulic drive control system comprising: a variable hydraulic displacement pump; a pump discharge means; volume control means connected to said discharge means; a constant displacement hydraulic motor; volume control input means connecting said volume control means to the input side of said motor; a motor discharge line connecting said motor and said pump input side; and a pressure sensing means connected to said pump discharge line and said motor input line for varying the displacement of said pump.
Claim 3
Dependent Claim
27 words
A hydraulic control system, as in claim 1 wherein: said pump is a variable displacement swash plate pump, and said motor is a fixed constant displacement motor.
Claim 4
Dependent Claim
161 words
An hydraulically operated, mechanical rotational energy control system comprising: rotational mechanical power source; a hydraulic pump driveably connected to said power source, said pump including a pump discharge means for varying the pressure and volume output of said pump discharge; a constant displacement fluid motor having an output shaft; a pump discharge line connected at one end to said pump; a fluid return line connecting said pump and said motor; a fluid input line connected to said motor; means connected between said pump discharge line and said motor input line for maintaining a constant volume of fluid to said motor; a variable load driveably connected to said motor output shaft; means connected to said discharge line, said motor input line, and said pump discharge means for controlling said pump discharge as a function of a pressure differential between said discharge line and said input line, whereby the fluid motor output is maintained at a predetermined RPM regardless of output load variations.
Claim 5
Dependent Claim
161 words
An hydraulically operated, mechanical rotational energy control system comprising: rotational mechanical power source; a hydraulic pump driveably connected to said power source, said pump including a pump discharge means for varying the pressure and volume output of said pump discharge; a constant displacement fluid motor having an output shaft; a pump discharge line connected at one end to said pump; a fluid return line connecting said pump and said motor; a fluid input line connected to said motor; means connected between said pump discharge line and said motor input line for maintaining a constant volume of fluid to said motor; a variable load driveably connected to said motor output shaft; means connected to said discharge line, said motor input line, and said pump discharge means for controlling said pump discharge as a function of a pressure differential between said discharge line and said input line, whereby the fluid motor output is maintained at a predetermined RPM regardless of output load variations.
Claim 6
Dependent Claim
17 words
A control system, as in claim 3, wherein: said pump discharge means includes a movable swash plate.
Claim 7
Dependent Claim
103 words
A control system, as in claim 4, wherein: said pump discharge control means includes a fluid chamber, a piston disposed in said chamber, a mechanical linkage arm connected to said piston and said swash plate, a pressure line from said pump discharge line to said fluid chamber on one side of said piston, a motor input fluid line connected to said fluid chamber on the opposite side of said piston, and biasing means connected to said piston, whereby fluid pressure differences between said fluid pump discharge line and said motor input line control swash plate angle changing the output of the fluid pump.
Claim 8
Dependent Claim
51 words
A control system, as in claim 5, including: a clutch engaged between said power source and said fluid pump; and pressure responsive means connected to said clutch and said pump discharge line for disengaging said clutch between said input power source and said fluid pump at a predetermined discharge line pressure.
Claim 9
Dependent Claim
24 words
A control system, as in claim 6, wherein: said volume control means includes a fluid pressure compensating means for a fluid temperature compensating means.
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) | 1979-10-26 | 1980-04-26 | 1980-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-10-26 | 1984-04-26 | 1984-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-10-26 | 1988-04-26 | 1988-10-26 | $7700.00 | Window Closed / Lapsed |