US3630121A - Excavating machines - Google Patents

Excavating machines Download PDF

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Publication number
US3630121A
US3630121A US877633A US3630121DA US3630121A US 3630121 A US3630121 A US 3630121A US 877633 A US877633 A US 877633A US 3630121D A US3630121D A US 3630121DA US 3630121 A US3630121 A US 3630121A
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US
United States
Prior art keywords
valve
boom
pressure
conduit
operating valve
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 - Lifetime
Application number
US877633A
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English (en)
Inventor
Kjell Anton Landaeus
Karl Oscar Olsson
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.)
Akermans Verkstad AB
Original Assignee
Akermans Verkstad AB
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 Akermans Verkstad AB filed Critical Akermans Verkstad AB
Application granted granted Critical
Publication of US3630121A publication Critical patent/US3630121A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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
    • E02F9/2203—Arrangements for controlling the attitude of actuators, e.g. speed, floating function
    • 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
    • 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
    • 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
    • F15B2211/31—Directional control characterised by the positions of the valve element
    • F15B2211/3144—Directional control characterised by the positions of the valve element the positions being continuously variable, e.g. as realised by proportional 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
    • F15B2211/315—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
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/635—Circuits providing pilot pressure to pilot pressure-controlled fluid circuit elements
    • F15B2211/6355—Circuits providing pilot pressure to pilot pressure-controlled fluid circuit elements having valve means
    • 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
    • F15B2211/77—Control of direction of movement of the output member
    • F15B2211/7741—Control of direction of movement of the output member with floating mode, e.g. using a direct connection between both lines of a double-acting cylinder
    • 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
    • F15B2211/85—Control during special operating conditions

Definitions

  • Cohen Attorney-Beveridge & De Grandi ABSTRACT A hydraulic system including a hydraulic cylinder operated by a pressure-actuated servo-controlled operating valve and a crossover valve to interconnect the fluid lines leading to the hydraulic cylinder operated by an electrically controlled valve interposed in a pressure line leading to the operating valve.
  • This invention relates to excavating and like machines having a boom, a hydraulic power unit-for raising and lowering the boom, an operating valve for controlling the supply of pressure medium to the hydraulic power unit of the boom, and a servo circuit including an operating lever for adjusting the operating valve.
  • a valve mechanism is connected in the servo line to the operating valve of the hydraulic power unit of the boom and that said valve mechanism is preferably adjustable by means of an electric switch into either of two positions, and in one of said two positions the operating valve of the hydraulic power unit of the boom is directly operable by means of the operating lever while in the other of said two positions the operating valve of the hydraulic power unit of the boom is directly operable by means of the operating lever when said lever is brought into position for raising of the boom, but a further valve is connected when the operating lever is brought into position for lowering of the boom and a given minimum pressure has'been attained, said valve being adapted to short circuit the operating lines of the hydraulic power unit of the boom so that the boom with ancillary parts will bear against the base under its own weight.
  • the circuitry illustrated in the drawing is adapted for use in a conventional hydraulically operated excavating machine having a subframe, a superstructure arranged for rotation on the subframe, a boom pivoted to the superstructure, and a bucket arm with bucket arranged on the boom.
  • a hydraulic power unit is arranged between the superstructure and boom of the excavating machine, and upon extension and shortening the hydraulic power unit respectively raises and lowers the boom.
  • the hydraulic power unit 10 is connected over lines 11 to a main directional valve 12.
  • the valve 12 is of the conventional type and can occupy three different main positions as well as intermediate positions. It is connected to a main pump 13 and a tank of pressure medium 14.
  • a servo circuit including a servo pump 15, a tank 16 and an operating lever 17 by which either side of the main valve 12 can be connected to the servo pump for moving the valve member of the main valve 12 in the desired direction.
  • the arrangement as hitherto described is conventional in excavating machines.
  • a directional valve 18 is connected to one of the servo lines leading to the operating valve 12, more particularly the line which is connected to the servo pump upon lowering of the boom.
  • the valve 18 is electrically operable by means of a switch 19 and can occupy two different positions. In the position illustrated in which the switch 19 is not cut in, the servo pressure medium is led directly to the main operating valve 12, as will appear from the drawing. When the switch 19 is cut in, however, the servo pressure medium is led to a directional valve 20 which is hereinafter termed floating position valve. This valve 20 is so loaded that it is actuated only when the servo pressure has reached a predetermined minimum pressure, for instance 40-50 kp/sq.cm.
  • valve 20 When this pressure is reached the piston in said valve 20 is moved from the position shown in the drawing so that the two lines 11 are connected to one another and also to the tank 14. When the directional valve 18 occupies the position shown in the drawing it will be seen that the valve 20 is connected to the tank 14.
  • the boom is operated by the illustrated arrangement in the following way.
  • the operating lever 17 Upon raising of the boom the operating lever 17 is moved to the right, causing servo pressure medium to flow from the servo pump to the upper end of the valve l2 which is thus moved downwards so that pressure medium flows from the main pump through the valve 12 and one line 11 to the hydraulic power unit 10.
  • the operating lever 17 Upon lowering of the boom, on the other hand, the operating lever 17 is moved to the left so that servo pressure medium flows to the lower end of the valve 12, causing pressure medium from the main pump to be supplied to the hydraulic power unit 10 through the other line 11.
  • a hydraulic cylinder adapted to be connected to a boom, a source of pressure fluid, a pressureactuated servo-controlled operating valve operable to selectively direct pressure fluid through a first hydraulic line to one end of the cylinder to raise the boom and through a second hydraulic line to the other end of the cylinder to lower the boom, and a servomechanism for actuating the operating valve, said servomechanism including a manually operated servo valve for selectively directing fluid under pressure through a first conduit connected to the operating valve to condition the operating valve to raise the boom and a second conduit connected to the operating valve to conditionthe operating valve to lower the boom, the improvement comprising, crossover conduit means connecting said first and said second hydraulic lines, pressure-actuated crossover valve means connected in said crossover conduit, and selectively operable valve means connected in said second conduit and movable between a normal position in which pressure fluid in said second conduit is directed to said operating valve to condition said operating valve to lower the boom, and a crossover position directing fluid in
  • said selectively operable valve means is an electrically controlled two-position valve.
  • a hydraulic cylinder adapted to be connected to a boom, a source of fluid pressure, and a hydraulic control system for directing fluid under pressure to said cylinder for raising and lowering the boom
  • said hydraulic control system comprises, in combination, a pressure-actuated servo-controlled operating valve operable to selectively direct pressure fluid through a first hydraulic line to one end of the hydraulic cylinder to raise the boom and through a second hydraulic line to the other end of the hydraulic cylinder to lower the boom, a servomechanism for actuating the operating valve, said servomechanism including a manually operated servo valve for selectively directing fluid under pressure through a first conduit connected to the operating valve to condition the operating valve to raise the boom and a second

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)
  • Operation Control Of Excavators (AREA)
  • Washing And Drying Of Tableware (AREA)
US877633A 1968-11-29 1969-11-18 Excavating machines Expired - Lifetime US3630121A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
SE16290/68A SE326666B (ru) 1968-11-29 1968-11-29

Publications (1)

Publication Number Publication Date
US3630121A true US3630121A (en) 1971-12-28

Family

ID=20302008

Family Applications (1)

Application Number Title Priority Date Filing Date
US877633A Expired - Lifetime US3630121A (en) 1968-11-29 1969-11-18 Excavating machines

Country Status (3)

Country Link
US (1) US3630121A (ru)
NO (1) NO121326B (ru)
SE (1) SE326666B (ru)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2554892A1 (de) * 1974-12-09 1976-06-16 Caterpillar Tractor Co Rueckstromkreis fuer hydrozylinder
FR2325973A1 (fr) * 1975-09-24 1977-04-22 Caterpillar Tractor Co Dispositif electrique de commande de flottement pour lame
US4034815A (en) * 1975-03-20 1977-07-12 Caterpillar Tractor Co. Blade lift float circuit for motor graders
US4099379A (en) * 1974-11-08 1978-07-11 Tadeusz Budzich Load responsive fluid control system
EP0092351A2 (en) * 1982-04-19 1983-10-26 Unimation Inc. Manipulator apparatus with energy efficient control
FR2537184A1 (fr) * 1982-12-03 1984-06-08 Orenstein & Koppel Ag Procede et circuit hydraulique pour economiser de l'energie lors de l'actionnement d'un cylindre de manoeuvre sur un excavateur hydraulique
EP0344420A1 (en) * 1988-04-07 1989-12-06 KABUSHIKI KAISHA KOBE SEIKO SHO also known as Kobe Steel Ltd. Hydraulic circuit for power shovel
EP0381778A1 (en) * 1988-08-02 1990-08-16 Kabushiki Kaisha Komatsu Seisakusho Moving speed regulator for hydraulically driven working machines
FR2647159A1 (fr) * 1989-05-16 1990-11-23 Rexroth Mannesmann Gmbh Bloc de commande a vannes
EP0623754A2 (de) * 1993-04-05 1994-11-09 Deere & Company Hydrauliksteuersystem
WO2004088144A1 (ja) * 2003-03-31 2004-10-14 Hitachi Construction Machinery Co., Ltd. 作業用車両の油圧駆動装置
US20050198951A1 (en) * 2002-11-19 2005-09-15 Volvo Construction Equipment Holding Sweden Ab System for handling a tool at a vehicle
US20070151442A1 (en) * 2005-12-12 2007-07-05 Linde Aktiengesellschaft Valve device
US20140360174A1 (en) * 2011-12-28 2014-12-11 Doosan Infracore Co., Ltd. Boom cylinder control circuit for construction machine

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2219967A (en) * 1940-10-29 Servomotor fob aircraft
US3133474A (en) * 1957-10-14 1964-05-19 Swift & Co Hydraulic feed means
US3220318A (en) * 1963-11-21 1965-11-30 John R Mcguire Hydraulic system
US3313316A (en) * 1964-06-01 1967-04-11 Clark Equipment Co Relief and anti-cavitation valve assembly
US3472127A (en) * 1967-12-12 1969-10-14 Caterpillar Tractor Co Control circuit for bulldozers used in pushing
US3508400A (en) * 1968-07-11 1970-04-28 Jean Mercier Position control system

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2219967A (en) * 1940-10-29 Servomotor fob aircraft
US3133474A (en) * 1957-10-14 1964-05-19 Swift & Co Hydraulic feed means
US3220318A (en) * 1963-11-21 1965-11-30 John R Mcguire Hydraulic system
US3313316A (en) * 1964-06-01 1967-04-11 Clark Equipment Co Relief and anti-cavitation valve assembly
US3472127A (en) * 1967-12-12 1969-10-14 Caterpillar Tractor Co Control circuit for bulldozers used in pushing
US3508400A (en) * 1968-07-11 1970-04-28 Jean Mercier Position control system

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4099379A (en) * 1974-11-08 1978-07-11 Tadeusz Budzich Load responsive fluid control system
DE2554892A1 (de) * 1974-12-09 1976-06-16 Caterpillar Tractor Co Rueckstromkreis fuer hydrozylinder
US4034815A (en) * 1975-03-20 1977-07-12 Caterpillar Tractor Co. Blade lift float circuit for motor graders
FR2325973A1 (fr) * 1975-09-24 1977-04-22 Caterpillar Tractor Co Dispositif electrique de commande de flottement pour lame
US4024796A (en) * 1975-09-24 1977-05-24 Caterpillar Tractor Co. Float control electrical circuit for a blade
EP0092351A2 (en) * 1982-04-19 1983-10-26 Unimation Inc. Manipulator apparatus with energy efficient control
EP0092351A3 (en) * 1982-04-19 1986-07-16 Unimation Inc. Manipulator apparatus with energy efficient control
FR2537184A1 (fr) * 1982-12-03 1984-06-08 Orenstein & Koppel Ag Procede et circuit hydraulique pour economiser de l'energie lors de l'actionnement d'un cylindre de manoeuvre sur un excavateur hydraulique
US5005466A (en) * 1988-04-07 1991-04-09 Kabushiki Kaisha Kobe Seiko Sho Cavitation-preventing pilot valve control system for power shovel hydraulic circuit
EP0344420A1 (en) * 1988-04-07 1989-12-06 KABUSHIKI KAISHA KOBE SEIKO SHO also known as Kobe Steel Ltd. Hydraulic circuit for power shovel
EP0381778A1 (en) * 1988-08-02 1990-08-16 Kabushiki Kaisha Komatsu Seisakusho Moving speed regulator for hydraulically driven working machines
EP0381778A4 (en) * 1988-08-02 1990-12-27 Kabushiki Kaisha Komatsu Seisakusho Moving speed regulator for hydraulically driven working machines
US5174190A (en) * 1988-08-02 1992-12-29 Komatsu Mec Corp. Moving speed regulator for hydraulically driven work implement
FR2647159A1 (fr) * 1989-05-16 1990-11-23 Rexroth Mannesmann Gmbh Bloc de commande a vannes
EP0623754A3 (de) * 1993-04-05 1995-03-01 Deere & Co Hydrauliksteuersystem.
EP0623754A2 (de) * 1993-04-05 1994-11-09 Deere & Company Hydrauliksteuersystem
EP0756089A2 (de) 1993-04-05 1997-01-29 Deere & Company Hydrauliksteuersystem
US20050198951A1 (en) * 2002-11-19 2005-09-15 Volvo Construction Equipment Holding Sweden Ab System for handling a tool at a vehicle
US7210395B2 (en) * 2002-11-19 2007-05-01 Volvo Construction Equipment Holding Sweden Ab System for handling a tool at a vehicle
WO2004088144A1 (ja) * 2003-03-31 2004-10-14 Hitachi Construction Machinery Co., Ltd. 作業用車両の油圧駆動装置
US20070151442A1 (en) * 2005-12-12 2007-07-05 Linde Aktiengesellschaft Valve device
US7617760B2 (en) * 2005-12-12 2009-11-17 Linde Material Handling Gmbh Valve device
US20140360174A1 (en) * 2011-12-28 2014-12-11 Doosan Infracore Co., Ltd. Boom cylinder control circuit for construction machine
US9651064B2 (en) * 2011-12-28 2017-05-16 Doosan Infracore Co., Ltd. Boom cylinder control circuit for construction machine

Also Published As

Publication number Publication date
NO121326B (ru) 1971-02-08
SE326666B (ru) 1970-07-27

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