IT1032464B - Perfezionamento nei sistemi idraulici con pompa a portata variabile - Google Patents

Perfezionamento nei sistemi idraulici con pompa a portata variabile

Info

Publication number
IT1032464B
IT1032464B IT48796/75A IT4879675A IT1032464B IT 1032464 B IT1032464 B IT 1032464B IT 48796/75 A IT48796/75 A IT 48796/75A IT 4879675 A IT4879675 A IT 4879675A IT 1032464 B IT1032464 B IT 1032464B
Authority
IT
Italy
Prior art keywords
improvement
flow pump
variable flow
hydraulic systems
hydraulic
Prior art date
Application number
IT48796/75A
Other languages
English (en)
Italian (it)
Original Assignee
Gen Signal Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Gen Signal Corp filed Critical Gen Signal Corp
Application granted granted Critical
Publication of IT1032464B publication Critical patent/IT1032464B/it

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/16Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/16Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • F15B11/161Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load
    • F15B11/165Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load for adjusting the pump output or bypass in response to demand
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/20Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205Systems with pumps
    • F15B2211/2053Type of pump
    • F15B2211/20546Type of pump variable capacity
    • F15B2211/20553Type of pump variable capacity with pilot circuit, e.g. for controlling a swash plate
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/20Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/25Pressure control functions
    • F15B2211/253Pressure margin control, e.g. pump pressure in relation to load pressure
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/30Directional control
    • F15B2211/305Directional control characterised by the type of valves
    • F15B2211/30505Non-return valves, i.e. check valves
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/30Directional control
    • F15B2211/305Directional control characterised by the type of valves
    • F15B2211/30525Directional control valves, e.g. 4/3-directional control valve
    • F15B2211/3053In combination with a pressure compensating valve
    • F15B2211/30535In combination with a pressure compensating valve the pressure compensating valve is arranged between pressure source and directional control valve
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/30Directional control
    • F15B2211/31Directional control characterised by the positions of the valve element
    • F15B2211/3144Directional control characterised by the positions of the valve element the positions being continuously variable, e.g. as realised by proportional valves
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/30Directional control
    • F15B2211/315Directional control characterised by the connections of the valve or valves in the circuit
    • F15B2211/3157Directional control characterised by the connections of the valve or valves in the circuit being connected to a pressure source, an output member and a return line
    • F15B2211/31576Directional control characterised by the connections of the valve or valves in the circuit being connected to a pressure source, an output member and a return line having a single pressure source and a single output member
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/30Directional control
    • F15B2211/35Directional control combined with flow control
    • F15B2211/351Flow control by regulating means in feed line, i.e. meter-in control
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/40Flow control
    • F15B2211/45Control of bleed-off flow, e.g. control of bypass flow to the return line
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/50Pressure control
    • F15B2211/505Pressure control characterised by the type of pressure control means
    • F15B2211/50509Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means
    • F15B2211/50536Pressure 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
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/50Pressure control
    • F15B2211/52Pressure control characterised by the type of actuation
    • F15B2211/528Pressure control characterised by the type of actuation actuated by fluid pressure
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/50Pressure control
    • F15B2211/57Control of a differential pressure
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/60Circuit components or control therefor
    • F15B2211/605Load sensing circuits
    • F15B2211/6051Load sensing circuits having valve means between output member and the load sensing circuit
    • F15B2211/6052Load sensing circuits having valve means between output member and the load sensing circuit using check valves
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/60Circuit components or control therefor
    • F15B2211/605Load sensing circuits
    • F15B2211/6051Load sensing circuits having valve means between output member and the load sensing circuit
    • F15B2211/6055Load sensing circuits having valve means between output member and the load sensing circuit using pressure relief valves
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/70Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/705Output members, e.g. hydraulic motors or cylinders or control therefor characterised by the type of output members or actuators
    • F15B2211/7051Linear output members
    • F15B2211/7053Double-acting output members
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/70Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/71Multiple output members, e.g. multiple hydraulic motors or cylinders
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00Fluid handling
    • Y10T137/2496Self-proportioning or correlating systems
    • Y10T137/2559Self-controlled branched flow systems
    • Y10T137/2574Bypass or relief controlled by main line fluid condition
    • Y10T137/2579Flow rate responsive
    • Y10T137/2582Including controlling main line flow
    • Y10T137/2584Relief or bypass closes as main opens
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00Fluid handling
    • Y10T137/8593Systems
    • Y10T137/87169Supply and exhaust
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00Fluid handling
    • Y10T137/8593Systems
    • Y10T137/87169Supply and exhaust
    • Y10T137/87177With bypass
    • Y10T137/87185Controlled by supply or exhaust valve

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Servomotors (AREA)
IT48796/75A 1974-03-28 1975-03-27 Perfezionamento nei sistemi idraulici con pompa a portata variabile IT1032464B (it)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US455830A US3911942A (en) 1974-03-28 1974-03-28 Compensated multifunction hydraulic system

Publications (1)

Publication Number Publication Date
IT1032464B true IT1032464B (it) 1979-05-30

Family

ID=23810441

Family Applications (1)

Application Number Title Priority Date Filing Date
IT48796/75A IT1032464B (it) 1974-03-28 1975-03-27 Perfezionamento nei sistemi idraulici con pompa a portata variabile

Country Status (8)

Country Link
US (1) US3911942A (uk)
JP (1) JPS6018844B2 (uk)
CA (1) CA1032063A (uk)
DE (1) DE2513919C2 (uk)
FR (1) FR2266024B1 (uk)
GB (1) GB1457731A (uk)
IT (1) IT1032464B (uk)
SE (1) SE402623B (uk)

Families Citing this family (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4142842A (en) * 1974-09-09 1979-03-06 Caterpillar Tractor Co. Dual source hydraulic steering system
US3987623A (en) * 1976-01-23 1976-10-26 Caterpillar Tractor Co. Controlled priority fluid system of a crawler type vehicle
US3982469A (en) * 1976-01-23 1976-09-28 Caterpillar Tractor Co. Apparatus for controlling work element operating pressures in a fluid system
US4037620A (en) * 1976-04-23 1977-07-26 Eaton Corporation Controller for fluid pressure operated devices
IT1077304B (it) * 1976-06-23 1985-05-04 Eaton Corp Regolatore per dispositivi azionati dalla pressione di un fluido
US4129987A (en) * 1977-10-17 1978-12-19 Gresen Manufacturing Company Hydraulic control system
US4215720A (en) * 1978-10-02 1980-08-05 General Signal Corporation Fluid control valve system
US4205864A (en) * 1978-10-12 1980-06-03 Caterpillar Tractor Co. Controlled demand priority hydraulic circuit
US4282898A (en) * 1979-11-29 1981-08-11 Caterpillar Tractor Co. Flow metering valve with operator selectable boosted flow
US4453451A (en) * 1980-11-10 1984-06-12 Fiatallis North America, Inc. Hydraulic steering system with automatic emergency pump flow control
US4545407A (en) * 1984-02-29 1985-10-08 United Technologies Corporation Jam compensating control valve
DE3710699C1 (de) * 1987-03-31 1988-08-18 Heilmeier & Weinlein Hydraulische Steuervorrichtung fuer eine Verbrauchergruppe
JPS6441498A (en) * 1987-08-07 1989-02-13 Teijin Seiki Co Ltd Controller for rudder surface
KR940009215B1 (ko) * 1989-03-22 1994-10-01 히다찌 겐끼 가부시기가이샤 토목ㆍ건설기계의 유압구동장치
JPH0374608A (ja) * 1989-08-10 1991-03-29 Nippon Air Brake Co Ltd 流量制御回路
EP0438606A4 (en) * 1989-08-16 1993-07-28 Hitachi Construction Machinery Co., Ltd. Valve device and hydraulic circuit device
DE29802498U1 (de) * 1998-02-13 1998-04-16 Heilmeier & Weinlein Staplersteuerung
SE512652C2 (sv) * 1999-04-20 2000-04-17 Bt Ind Ab Anordning för, och förfarande vid, förflyttning av lastbärare hos industritruck
DE102007054134A1 (de) * 2007-11-14 2009-05-20 Hydac Filtertechnik Gmbh Hydraulische Ventilvorrichtung
US8813486B2 (en) * 2011-02-28 2014-08-26 Caterpillar Inc. Hydraulic control system having cylinder stall strategy

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2892312A (en) * 1958-01-27 1959-06-30 Deere & Co Demand compensated hydraulic system
US3602104A (en) * 1969-07-08 1971-08-31 Eaton Yale & Towne Pressure-compensated flow control
US3718159A (en) * 1971-01-20 1973-02-27 Hydraulic Industries Control valve
FR2173248B1 (uk) * 1972-02-24 1978-02-03 Daikin Ind Ltd
US3782404A (en) * 1972-06-14 1974-01-01 Commercial Shearing Adjustable, metered, directional flow control arrangements

Also Published As

Publication number Publication date
FR2266024A1 (uk) 1975-10-24
CA1032063A (en) 1978-05-30
SE402623B (sv) 1978-07-10
GB1457731A (en) 1976-12-08
FR2266024B1 (uk) 1980-09-12
DE2513919C2 (de) 1982-12-30
DE2513919A1 (de) 1975-10-09
JPS50130981A (uk) 1975-10-16
US3911942A (en) 1975-10-14
JPS6018844B2 (ja) 1985-05-13
SE7503395L (uk) 1975-09-29

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