GB1258346A - - Google Patents
Info
- Publication number
- GB1258346A GB1258346A GB1258346DA GB1258346A GB 1258346 A GB1258346 A GB 1258346A GB 1258346D A GB1258346D A GB 1258346DA GB 1258346 A GB1258346 A GB 1258346A
- Authority
- GB
- United Kingdom
- Prior art keywords
- valve
- line
- pressure
- control
- supply
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
- F15B11/161—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load
- F15B11/162—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load for giving priority to particular servomotors or users
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
- F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
- F15B13/0416—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor with means or adapted for load sensing
- F15B13/0417—Load sensing elements; Internal fluid connections therefor; Anti-saturation or pressure-compensation valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/205—Systems with pumps
- F15B2211/2053—Type of pump
- F15B2211/20538—Type of pump constant capacity
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/205—Systems with pumps
- F15B2211/2053—Type of pump
- F15B2211/20546—Type of pump variable capacity
- F15B2211/20553—Type of pump variable capacity with pilot circuit, e.g. for controlling a swash plate
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/25—Pressure control functions
- F15B2211/253—Pressure margin control, e.g. pump pressure in relation to load pressure
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/30—Directional control
- F15B2211/305—Directional control characterised by the type of valves
- F15B2211/30505—Non-return valves, i.e. check valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/30—Directional control
- F15B2211/305—Directional control characterised by the type of valves
- F15B2211/30525—Directional control valves, e.g. 4/3-directional control valve
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/30—Directional control
- F15B2211/305—Directional control characterised by the type of valves
- F15B2211/30525—Directional control valves, e.g. 4/3-directional control valve
- F15B2211/3053—In combination with a pressure compensating valve
- F15B2211/30535—In combination with a pressure compensating valve the pressure compensating valve is arranged between pressure source and directional control valve
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/30—Directional control
- F15B2211/31—Directional control characterised by the positions of the valve element
- F15B2211/3105—Neutral or centre positions
- F15B2211/3111—Neutral or centre positions the pump port being closed in the centre position, e.g. so-called closed centre
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/30—Directional control
- F15B2211/35—Directional control combined with flow control
- F15B2211/351—Flow control by regulating means in feed line, i.e. meter-in control
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/50—Pressure control
- F15B2211/505—Pressure control characterised by the type of pressure control means
- F15B2211/50509—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means
- F15B2211/50536—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means using unloading valves controlling the supply pressure by diverting fluid to the return line
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/50—Pressure control
- F15B2211/515—Pressure control characterised by the connections of the pressure control means in the circuit
- F15B2211/5151—Pressure control characterised by the connections of the pressure control means in the circuit being connected to a pressure source and a directional control valve
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/50—Pressure control
- F15B2211/57—Control of a differential pressure
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/60—Circuit components or control therefor
- F15B2211/605—Load sensing circuits
- F15B2211/6051—Load sensing circuits having valve means between output member and the load sensing circuit
- F15B2211/6052—Load sensing circuits having valve means between output member and the load sensing circuit using check valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/60—Circuit components or control therefor
- F15B2211/605—Load sensing circuits
- F15B2211/6051—Load sensing circuits having valve means between output member and the load sensing circuit
- F15B2211/6054—Load sensing circuits having valve means between output member and the load sensing circuit using shuttle valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/60—Circuit components or control therefor
- F15B2211/605—Load sensing circuits
- F15B2211/6051—Load sensing circuits having valve means between output member and the load sensing circuit
- F15B2211/6055—Load sensing circuits having valve means between output member and the load sensing circuit using pressure relief valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
- F15B2211/705—Output members, e.g. hydraulic motors or cylinders or control therefor characterised by the type of output members or actuators
- F15B2211/7051—Linear output members
- F15B2211/7053—Double-acting output members
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
- F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
1,258,346. Hydraulic motor control circuits. BORG-WARNER CORP. Aug.22, 1969 [Sept. 6, 1968], No.42045/69. Heading F1P. At least two hydraulic motors 22, 26, Fig. 1 each controlled by a three-position closed-centre spool valve 21, 25 are connected in parallel to a pump delivery line 55 through valved branch lines 77, 78, the line 55 is also connected to one end of a by-pass valve 18 having a reservoir return line 56 and having its other end also connected to reservoir through a non-return valve 19 and connected to a control pressure line 60 which is connected to control parts 73, 74 of each valve 21, 25 through a line 88, a non-return valve 32, a line 86, a control signal supply means e.g. a shuttle valve 31 and lines 83, 84 the arrangement being that with both valves 21, 25 in a motor actuating position the motor actuating pressure at say each port 65 is transmitted through port 73, line 83 and shuttle valve 31 to line 86 and the higher motor actuating pressure is then transmitted through the associated valve 32 to the control pressure line 60 and the by-pass valve 18 which is thus held in such a position that the supply pressure in line 53 is adjusted to the needs of the motor requiring the higher pressure. Each of the two supply passages in each valve 21, 25 has an operator actuated variable throttle orifice. The valve in lines 77, 78 connecting supply line 55 to control valve 21 is a load check valve 34, whereas that in lines 77, 78 leading to control valve 25 is a flow control throttle valve 27 comprising a spring-loaded double-cup shaped ported piston 91, Fig. 2 in a base 92 which provides a pressure chamber 104 connected by a restricted line 87 to line 86 and connected by a line 113 and a relief valve 28 to a reservoir 36. The valve 27 serves (a) to provide a constant pressure drop across valve 25 irrespective of pressure supply variations (b) to limit maximum flow and pressure (c) to act as a load check valve and (d) to supply a low stand-by pressure to valve 25 when the latter is in its neutral central position. In a modification the control signal supply means instead of being a shuttle valve comprises tapered notches (146), (147), Fig. 6 (not shown) in the central land (143) of the spool (141) of a control valve 140. In a further modification pressure fluid is supplied by a variable displacement pump controlled by the pressure in the control pressure line.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US75796168A | 1968-09-06 | 1968-09-06 |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1258346A true GB1258346A (en) | 1971-12-30 |
Family
ID=25049891
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB1258346D Expired GB1258346A (en) | 1968-09-06 | 1969-08-22 |
Country Status (8)
Country | Link |
---|---|
BE (1) | BE738467A (en) |
DE (1) | DE1944822A1 (en) |
ES (1) | ES371131A1 (en) |
FR (1) | FR2017525A1 (en) |
GB (1) | GB1258346A (en) |
NL (1) | NL6913480A (en) |
SE (1) | SE347553B (en) |
ZA (1) | ZA695984B (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2500584A4 (en) * | 2009-11-10 | 2015-05-20 | Hunan Sany Intelligent Control | Multi-way valve, hydraulic device and concrete pump vehicle |
CN111089087A (en) * | 2018-10-24 | 2020-05-01 | 罗伯特·博世有限公司 | Assembly for a working hydraulic system, method and working hydraulic system |
Families Citing this family (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5438720B1 (en) * | 1971-05-11 | 1979-11-22 | ||
DE2514624C3 (en) * | 1975-04-03 | 1986-10-23 | Danfoss A/S, Nordborg | Control device for at least one hydraulically operated double-acting consumer |
US4024797A (en) * | 1975-10-28 | 1977-05-24 | Caterpillar Tractor Co. | Spring centered balanced resolver valve |
US3982469A (en) * | 1976-01-23 | 1976-09-28 | Caterpillar Tractor Co. | Apparatus for controlling work element operating pressures in a fluid system |
US4193263A (en) * | 1978-07-27 | 1980-03-18 | Borg-Warner Corporation | Fluid control system with individually variable flow control mechanism for each control section |
US4352375A (en) * | 1980-04-14 | 1982-10-05 | Commercial Shearing, Inc. | Control valves |
FR2562632B1 (en) * | 1984-04-18 | 1986-12-12 | Bennes Marrel | PROPORTIONAL TYPE HYDRAULIC VALVE WITH INFORMATION ON THE HIGHEST PRESSURES IN THE CIRCUITS OF USE |
DE10027382A1 (en) | 2000-06-02 | 2001-12-06 | Bosch Gmbh Robert | Hydraulic control device |
-
1969
- 1969-08-20 ZA ZA695984*A patent/ZA695984B/en unknown
- 1969-08-22 GB GB1258346D patent/GB1258346A/en not_active Expired
- 1969-08-22 SE SE11682/69A patent/SE347553B/xx unknown
- 1969-09-02 ES ES371131A patent/ES371131A1/en not_active Expired
- 1969-09-04 NL NL6913480A patent/NL6913480A/xx unknown
- 1969-09-04 DE DE19691944822 patent/DE1944822A1/en active Pending
- 1969-09-05 FR FR6930315A patent/FR2017525A1/fr not_active Withdrawn
- 1969-09-05 BE BE738467D patent/BE738467A/xx not_active IP Right Cessation
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2500584A4 (en) * | 2009-11-10 | 2015-05-20 | Hunan Sany Intelligent Control | Multi-way valve, hydraulic device and concrete pump vehicle |
CN111089087A (en) * | 2018-10-24 | 2020-05-01 | 罗伯特·博世有限公司 | Assembly for a working hydraulic system, method and working hydraulic system |
Also Published As
Publication number | Publication date |
---|---|
ZA695984B (en) | 1971-03-31 |
ES371131A1 (en) | 1971-08-16 |
DE1944822A1 (en) | 1970-03-12 |
SE347553B (en) | 1972-08-07 |
BE738467A (en) | 1970-02-16 |
FR2017525A1 (en) | 1970-05-22 |
NL6913480A (en) | 1970-03-10 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed | ||
PLNP | Patent lapsed through nonpayment of renewal fees |