DE3762639D1 - Stroemungsrueckgewinnungssystem fuer hydraulikkreislaeufe mit pumpen und druckkompensierten verteilungsventilen fuer arbeitsglieder von erdbewegungsmaschinen. - Google Patents

Stroemungsrueckgewinnungssystem fuer hydraulikkreislaeufe mit pumpen und druckkompensierten verteilungsventilen fuer arbeitsglieder von erdbewegungsmaschinen.

Info

Publication number
DE3762639D1
DE3762639D1 DE8787830015T DE3762639T DE3762639D1 DE 3762639 D1 DE3762639 D1 DE 3762639D1 DE 8787830015 T DE8787830015 T DE 8787830015T DE 3762639 T DE3762639 T DE 3762639T DE 3762639 D1 DE3762639 D1 DE 3762639D1
Authority
DE
Germany
Prior art keywords
pumps
recovery system
hydraulic circuits
flow recovery
pressure compensated
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 - Fee Related
Application number
DE8787830015T
Other languages
English (en)
Inventor
Piero Tha
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Trinova SpA
Original Assignee
Trinova SpA
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 Trinova SpA filed Critical Trinova SpA
Application granted granted Critical
Publication of DE3762639D1 publication Critical patent/DE3762639D1/de
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E02F9/2278—Hydraulic circuits
    • E02F9/2292—Systems with two or more pumps
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E02F9/2221—Control of flow rate; Load sensing arrangements
    • E02F9/2225—Control of flow rate; Load sensing arrangements using pressure-compensating valves
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E02F9/2221—Control of flow rate; Load sensing arrangements
    • E02F9/2232—Control of flow rate; Load sensing arrangements using one or more variable displacement pumps
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E02F9/2278—Hydraulic circuits
    • E02F9/2296—Systems with a variable displacement pump
    • 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
    • F15B11/024—Systems essentially incorporating special features for controlling the speed or actuating force of an output member by means of differential connection of the servomotor lines, e.g. regenerative circuits
    • 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
    • F15B11/024—Systems essentially incorporating special features for controlling the speed or actuating force of an output member by means of differential connection of the servomotor lines, e.g. regenerative circuits
    • F15B2011/0243—Systems essentially incorporating special features for controlling the speed or actuating force of an output member by means of differential connection of the servomotor lines, e.g. regenerative circuits the regenerative circuit being activated or deactivated automatically
    • 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
    • F15B2211/205—Systems with pumps
    • F15B2211/20576—Systems with pumps with multiple pumps
    • 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
    • F15B2211/305—Directional control characterised by the type of valves
    • F15B2211/3056—Assemblies of multiple valves
    • F15B2211/30565—Assemblies of multiple valves having multiple valves for a single output member, e.g. for creating higher valve function by use of multiple valves like two 2/2-valves replacing a 5/3-valve
    • F15B2211/3058—Assemblies of multiple valves having multiple valves for a single output member, e.g. for creating higher valve function by use of multiple valves like two 2/2-valves replacing a 5/3-valve having additional valves for interconnecting the fluid chambers of a double-acting actuator, e.g. for regeneration mode or for floating mode
    • 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
    • F15B2211/315—Directional control characterised by the connections of the valve or valves in the circuit
    • F15B2211/3157—Directional 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
    • F15B2211/31576—Directional 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
    • 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
    • F15B2211/32—Directional control characterised by the type of actuation
    • F15B2211/329—Directional control characterised by the type of actuation actuated by fluid 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
    • F15B2211/50—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
    • F15B2211/50545—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means using braking valves to maintain a back 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
    • F15B2211/50—Pressure control
    • F15B2211/505—Pressure control characterised by the type of pressure control means
    • F15B2211/50563—Pressure control characterised by the type of pressure control means the pressure control means controlling a differential pressure
    • F15B2211/50581—Pressure control characterised by the type of pressure control means the pressure control means controlling a differential pressure using counterbalance 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
    • F15B2211/50—Pressure control
    • F15B2211/515—Pressure control characterised by the connections of the pressure control means in the circuit
    • F15B2211/5156—Pressure control characterised by the connections of the pressure control means in the circuit being connected to a return line 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
    • F15B2211/55—Pressure control for limiting a pressure up to a maximum pressure, e.g. by using a pressure relief 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
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
    • F15B2211/7135—Combinations of output members of different types, e.g. single-acting cylinders with rotary motors
    • 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
    • F15B2211/7142—Multiple output members, e.g. multiple hydraulic motors or cylinders the output members being arranged in multiple groups
    • 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
    • F15B2211/78—Control of multiple 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
    • F15B2211/80—Other types of control related to particular problems or conditions
    • F15B2211/88—Control measures for saving energy

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Operation Control Of Excavators (AREA)
  • Flow Control (AREA)
DE8787830015T 1986-09-24 1987-01-19 Stroemungsrueckgewinnungssystem fuer hydraulikkreislaeufe mit pumpen und druckkompensierten verteilungsventilen fuer arbeitsglieder von erdbewegungsmaschinen. Expired - Fee Related DE3762639D1 (de)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
IT67731/86A IT1195178B (it) 1986-09-24 1986-09-24 Sistema di recupero di portata per circuiti idraulici con pompe e di stributori compensati in pressione per organi di lavoro di macchine movimento terra

Publications (1)

Publication Number Publication Date
DE3762639D1 true DE3762639D1 (de) 1990-06-13

Family

ID=11304850

Family Applications (1)

Application Number Title Priority Date Filing Date
DE8787830015T Expired - Fee Related DE3762639D1 (de) 1986-09-24 1987-01-19 Stroemungsrueckgewinnungssystem fuer hydraulikkreislaeufe mit pumpen und druckkompensierten verteilungsventilen fuer arbeitsglieder von erdbewegungsmaschinen.

Country Status (7)

Country Link
EP (1) EP0262098B1 (de)
JP (1) JP2564308B2 (de)
AT (1) ATE52560T1 (de)
DE (1) DE3762639D1 (de)
ES (1) ES2015967B3 (de)
GR (1) GR3000479T3 (de)
IT (1) IT1195178B (de)

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IT1208866B (it) * 1987-04-14 1989-07-10 Chs Vickers Spa Circuito idraulico di comando per organi di lavoro di macchine movimento terra con circuito di sovrali mentazione
AU603907B2 (en) * 1987-06-30 1990-11-29 Hitachi Construction Machinery Co. Ltd. Hydraulic drive system
DE3883690T2 (de) * 1987-10-05 1994-03-17 Hitachi Construction Machinery Hydraulisches Antriebssystem.
DE3844401C2 (de) * 1988-12-30 1994-10-06 Rexroth Mannesmann Gmbh Regeleinrichtung für eine Verstellpumpe
JP2839625B2 (ja) * 1990-03-05 1998-12-16 日立建機株式会社 油圧駆動装置
US5220862A (en) * 1992-05-15 1993-06-22 Caterpillar Inc. Fluid regeneration circuit
JP2992434B2 (ja) * 1993-12-02 1999-12-20 日立建機株式会社 建設機械の油圧制御装置
US5755260A (en) * 1994-09-29 1998-05-26 Samsung Heavy Industries Co., Ltd. Mono-block control valve with regeneration conduit
JP3478931B2 (ja) * 1996-09-20 2003-12-15 新キャタピラー三菱株式会社 油圧回路
GB2344809B (en) * 1998-12-16 2002-10-02 Bamford Excavators Ltd Earth moving apparatus
DE10004905C2 (de) * 2000-02-04 2002-10-24 Orenstein & Koppel Ag Verfahren und Vorrichtung zur Steuerung eines Hubzylinders insbesondere von Arbeitsmaschinen
EP1591669A4 (de) * 2003-01-14 2010-12-08 Hitachi Construction Machinery Hydraulische arbeitsmaschine
JP4209705B2 (ja) 2003-03-17 2009-01-14 日立建機株式会社 作業機の油圧回路
US20220307527A1 (en) * 2021-03-23 2022-09-29 Cnh Industrial America Llc System to reduce line loss in pressure control hydraulic circuit

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1401412A (fr) * 1964-04-23 1965-06-04 Faucheux Ets Dispositif de correction par procédé hydraulique du mouvement d'un organe mécanique, par exemple d'une benne, à l'extrémité d'un bras de levage
US3467126A (en) * 1966-03-21 1969-09-16 Hydranamic Systems Corp Hydraulic load compensating directional control valve
US4364304A (en) * 1976-01-21 1982-12-21 Danfoss A/S Arrangement for influencing the operating quantity of a servomotor
US4216702A (en) * 1978-05-01 1980-08-12 Eaton Yale Ltd. Pressure sensing regenerative hydraulic system
US4383412A (en) * 1979-10-17 1983-05-17 Cross Manufacturing, Inc. Multiple pump load sensing system
DE3245288A1 (de) * 1982-12-03 1984-06-14 O & K Orenstein & Koppel Ag, 1000 Berlin Verfahren zur einsparung von energie beim stellen eines ausruestungszylinders an einem hydraulikbagger durch eine hydraulikschaltung
IT1234937B (it) * 1985-02-14 1992-06-02 Cinotto Hydraulic Sistema antisaturazione per circuiti idraulici di comando con pompe e distributori compensati in pressione per organi di lavoro di macchine movimento terra
IT1187892B (it) * 1986-02-04 1987-12-23 Chs Vickers Spa Circuito idraulico di comando per organi di lavoro di macchine movimento terra con frenatura centralizzata degli attuatori

Also Published As

Publication number Publication date
GR3000479T3 (en) 1991-06-28
IT8667731A0 (it) 1986-09-24
ES2015967B3 (es) 1990-09-16
EP0262098A1 (de) 1988-03-30
JPS6383808A (ja) 1988-04-14
EP0262098B1 (de) 1990-05-09
JP2564308B2 (ja) 1996-12-18
IT1195178B (it) 1988-10-12
ATE52560T1 (de) 1990-05-15

Similar Documents

Publication Publication Date Title
US3987623A (en) Controlled priority fluid system of a crawler type vehicle
DE3762639D1 (de) Stroemungsrueckgewinnungssystem fuer hydraulikkreislaeufe mit pumpen und druckkompensierten verteilungsventilen fuer arbeitsglieder von erdbewegungsmaschinen.
JPS6011706A (ja) １つのポンプとこのポンプによつて負荷される少なくとも２つの液力作業装置とを有する液力式装置
KR940701487A (ko) 토목·건설 기계의 유압회로장치
EP0489817B1 (de) Lastdruckwiederholungsschaltung
US4215720A (en) Fluid control valve system
US4055046A (en) Control system having override for fluid operated work elements
EP0160289A3 (de) Hydraulisches Regelsystem
US3878679A (en) Compensated multi-function hydraulic system
JPS6018844B2 (ja) 補償型の多機能液圧装置
AU645461B2 (en) Load sensing hydraulic control system
US5680759A (en) Straight travelling apparatus for heavy construction equipment
EP0709579B1 (de) Vorrichtung für Geradeausfahrt bei schweren Baumaschinen
SE8002302L (sv) Ventilanleggning for reglering av funktionen hos en hydraulmotor, serskilt en hydraulcylinder
DE3573453D1 (en) Anti-saturation system for hydraulic control circuits for working members of earth-moving machines
EP0404946A4 (en) Hydraulic circuit device of construction vehicle
EP0550257B1 (de) Einrichtung zur Steuerung mehrerer Servomotoren
US3834163A (en) Control valve for hydraulically operated implements
GB1057752A (en) Control system for hydraulically operated equipment such as excavators
ES8402641A1 (es) "perfeccionamientos en los sistemas de regulacion hidraulicos".
KR960008717Y1 (ko) 블도저 블레이드 유압식 작동기
KR970011612B1 (ko) 중장비의 주행구동시스템
US4787204A (en) Common relief valve
JPS5932682B2 (ja) 圧力流体回路
JPH0319402B2 (de)

Legal Events

Date Code Title Description
8364 No opposition during term of opposition
8339 Ceased/non-payment of the annual fee