US3858393A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Load responsive fluid control valves
Assignee: Individual
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Filing: 1973-07-06
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Granted: 1975-01-07
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Expires: 1993-07-06
Abstract
Abstract A direction and flow control valve for use in a central fluid power load responsive system having plurality of loads. The valve maintains a selected constant flow level for control of both positive and negative loads, irrespective of the change in the load magnitude or change in the fluid pressure, supplied to the valve. System is powered by a single variable volume pump equipped with a load responsive control, which automatically maintains pump discharge pressure at a level higher than the pressure required by the system''s largest load. Each direction and flow control valve is equipped with a differential pressure regulating control, which is responsive to the load pressure for controlling the negative loads and preferably a second differential pressure regulating control for controlling the positive loads.
Inventors
- 👤 Tadeusz Budzich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:19
CPC Classifications
F; F15; F15B; F15B13/00; F15B13/02; F15B13/04; F15B11/00; F15B11/02; F15B11/04; F15B11/044; F15B11/0445; F15B13/0401; F15B13/0402; F15B13/0416; F15B13/0417; F15B2211/00; F15B2211/20; F15B2211/205; F15B2211/2053; F15B2211/20546; F15B2211/20553; F15B2211/25; F15B2211/30; F15B2211/305; F15B2211/30505; F15B2211/30525; F15B2211/3053; F15B2211/30535; F15B2211/3055; F15B2211/60; F15B2211/605; F15B2211/70; F15B2211/71; F15B2211/76; F15B2211/761
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
170 words
A load responsive control system comprising in combination a variable flow pump having volume output control responsive to a pressure load signal, a fluid motor operating a load, and a valve assembly between said pump and said motor, said valve asseMbly comprising a housing having a fluid inlet chamber, a fluid load chamber, a fluid outlet chamber and exhaust means, first valve means for selectively interconnecting said load chamber with said inlet chamber and said outlet chamber to meter fluid flow to and from said load chamber, second valve means interconnecting said outlet chamber and said exhaust means operable to maintain a constant pressure difference between said load chamber and said outlet chamber when said load and outlet chambers are interconnected and said load chamber is pressurized, and a load pressure signal line for transmitting a control signal from said load chamber to said volume output control of said variable flow pump, said control being operable to maintain a constant pressure differential between said inlet chamber and said load chamber.
Claim 2
Dependent Claim
170 words
A load responsive control system comprising in combination a variable flow pump having volume output control responsive to a pressure load signal, a fluid motor operating a load, and a valve assembly between said pump and said motor, said valve asseMbly comprising a housing having a fluid inlet chamber, a fluid load chamber, a fluid outlet chamber and exhaust means, first valve means for selectively interconnecting said load chamber with said inlet chamber and said outlet chamber to meter fluid flow to and from said load chamber, second valve means interconnecting said outlet chamber and said exhaust means operable to maintain a constant pressure difference between said load chamber and said outlet chamber when said load and outlet chambers are interconnected and said load chamber is pressurized, and a load pressure signal line for transmitting a control signal from said load chamber to said volume output control of said variable flow pump, said control being operable to maintain a constant pressure differential between said inlet chamber and said load chamber.
Claim 3
Dependent Claim
219 words
A load responsive control system comprising a variable flow pump having volume output control responsive to a pressure load signal, a plurality of fluid motors, a control valve for each motor, at least one of said control valves comprising a housing having a fluid inlet chamber, a fluid supply chamber, a fluid load chamber, and fluid exhaust means, first valve means for selectively interconnecting said fluid load chamber with said fluid supply chamber and fluid outlet chamber to meter fluid flow to and from said load chamber, second valve means interconnecting said outlet chamber and said exhaust means operable to maintain a constant pressure difference between said fluid outlet chamber and said fluid load chamber when said load chamber is pressurized and connected to said outlet chamber, and third valve means interconnecting said fluid inlet chamber and said supply chamber and operable to maintain a constant pressure difference between said fluid load chamber and said fluid supply chamber when said chambers are interconnected by said first valve means and said supply chamber is pressurized, and a load pressure signal line for transmitting a control signal from said load chamber to said volume output control of said variable flow pump, said control being operable to maintain a constant pressure differential between said inlet chamber and said load chamber connected thereto.
Claim 4
Dependent Claim
219 words
A load responsive control system comprising a variable flow pump having volume output control responsive to a pressure load signal, a plurality of fluid motors, a control valve for each motor, at least one of said control valves comprising a housing having a fluid inlet chamber, a fluid supply chamber, a fluid load chamber, and fluid exhaust means, first valve means for selectively interconnecting said fluid load chamber with said fluid supply chamber and fluid outlet chamber to meter fluid flow to and from said load chamber, second valve means interconnecting said outlet chamber and said exhaust means operable to maintain a constant pressure difference between said fluid outlet chamber and said fluid load chamber when said load chamber is pressurized and connected to said outlet chamber, and third valve means interconnecting said fluid inlet chamber and said supply chamber and operable to maintain a constant pressure difference between said fluid load chamber and said fluid supply chamber when said chambers are interconnected by said first valve means and said supply chamber is pressurized, and a load pressure signal line for transmitting a control signal from said load chamber to said volume output control of said variable flow pump, said control being operable to maintain a constant pressure differential between said inlet chamber and said load chamber connected thereto.
Claim 5
Dependent Claim
245 words
A load responsive control system comprising a variable flow pump having volume output control responsive to a pressure load signal, a plurality of fluid motors, a control valve for each motor, at least one of said control valves comprising a housing having a fluid inlet chamber, a fluid supply chamber, a fluid load chamber, a fluid outlet chamber and a fluid exhaust means, first valve means in first bore means for selectively interconnecting said fluid load chamber with said fluid supply chamber and said fluid outlet chamber to meter fluid flow to and from said load chamber, second valve means interconnecting said outlet chamber and said exhaust means and operable to provide a passage between said outlet chamber and said exhaust means open above preselected pressure level in said load chamber connected by said first bore means to said supply chamber and progressively reduce said passage opening upon pressure in said load chamber connected by said valve means to the supply chamber dropping below said preselected pressure level, and third valve means interconnecting said fluid inlet chamber and said supply chamber operable to maintain a constant pressure difference between said fluid supply chambers and said fluid load chamber connected thereto, and a load pressure signal line for transmitting a control signal from said load chamber to said volume output control of said variable flow pump, said control being operable to maintain a constant pressure difference between said inlet chamber and said load chamber connected thereto.
Claim 6
Dependent Claim
245 words
A load responsive control system comprising a variable flow pump having volume output control responsive to a pressure load signal, a plurality of fluid motors, a control valve for each motor, at least one of said control valves comprising a housing having a fluid inlet chamber, a fluid supply chamber, a fluid load chamber, a fluid outlet chamber and a fluid exhaust means, first valve means in first bore means for selectively interconnecting said fluid load chamber with said fluid supply chamber and said fluid outlet chamber to meter fluid flow to and from said load chamber, second valve means interconnecting said outlet chamber and said exhaust means and operable to provide a passage between said outlet chamber and said exhaust means open above preselected pressure level in said load chamber connected by said first bore means to said supply chamber and progressively reduce said passage opening upon pressure in said load chamber connected by said valve means to the supply chamber dropping below said preselected pressure level, and third valve means interconnecting said fluid inlet chamber and said supply chamber operable to maintain a constant pressure difference between said fluid supply chambers and said fluid load chamber connected thereto, and a load pressure signal line for transmitting a control signal from said load chamber to said volume output control of said variable flow pump, said control being operable to maintain a constant pressure difference between said inlet chamber and said load chamber connected thereto.
Claim 7
Dependent Claim
77 words
A load responsive control system as set forth in claim 2 wherein said first valve means includes a valve spool axially movable and guided in a spool bore, said valve spool having lands, said valve spool having a neutral position wherein said lands isolate said lOad chamber from said fluid supply chamber and being movable therein to selectively connect said chambers, said second and third valve means being operable responsive to fluid pressure in said load chamber.
Claim 8
Dependent Claim
44 words
A load responsive control system as set forth in claim 4 wherein said valve spool is operable to establish fluid communication first between said load chamber and said second and third valve means and then between said load chamber and supply and outlet chambers.
Claim 9
Dependent Claim
53 words
A load responsive control system as set forth in claim 2 wherein said load pressure signal line includes a pressure signal passage and a check valve in said pressure signal passage, said check valve permitting only the highest of load signals to be transmitted to volume output control of said variable flow pump.
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) | 1978-01-06 | 1978-07-08 | 1979-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-06 | 1982-07-08 | 1983-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-06 | 1986-07-08 | 1987-01-07 | $7700.00 | Window Closed / Lapsed |