EP0345640A1 - Dispositif pour la conservation de l'assiette d'un outil porté par des chargeurs - Google Patents

Dispositif pour la conservation de l'assiette d'un outil porté par des chargeurs Download PDF

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Publication number
EP0345640A1
EP0345640A1 EP89109918A EP89109918A EP0345640A1 EP 0345640 A1 EP0345640 A1 EP 0345640A1 EP 89109918 A EP89109918 A EP 89109918A EP 89109918 A EP89109918 A EP 89109918A EP 0345640 A1 EP0345640 A1 EP 0345640A1
Authority
EP
European Patent Office
Prior art keywords
valve
pressure
boom
bucket
line
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.)
Granted
Application number
EP89109918A
Other languages
German (de)
English (en)
Other versions
EP0345640B1 (fr
Inventor
Bruce Kevin Fryk
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.)
Deere and Co
Original Assignee
Deere and Co
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 Deere and Co filed Critical Deere and Co
Publication of EP0345640A1 publication Critical patent/EP0345640A1/fr
Application granted granted Critical
Publication of EP0345640B1 publication Critical patent/EP0345640B1/fr
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
    • E02F9/2221—Control of flow rate; Load sensing arrangements
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F3/00—Dredgers; Soil-shifting machines
    • E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
    • E02F3/28—Dredgers; Soil-shifting machines mechanically-driven with digging tools mounted on a dipper- or bucket-arm, i.e. there is either one arm or a pair of arms, e.g. dippers, buckets
    • E02F3/36—Component parts
    • E02F3/42—Drives for dippers, buckets, dipper-arms or bucket-arms
    • E02F3/43—Control of dipper or bucket position; Control of sequence of drive operations
    • E02F3/431—Control of dipper or bucket position; Control of sequence of drive operations for bucket-arms, front-end loaders, dumpers or the like
    • E02F3/432—Control of dipper or bucket position; Control of sequence of drive operations for bucket-arms, front-end loaders, dumpers or the like for keeping the bucket in a predetermined position or attitude
    • E02F3/433—Control of dipper or bucket position; Control of sequence of drive operations for bucket-arms, front-end loaders, dumpers or the like for keeping the bucket in a predetermined position or attitude horizontal, e.g. self-levelling

Definitions

  • the invention relates to a hydraulic control device for adjusting the level of a bucket tiltably arranged on a pivotable boom, at least one driving element being provided for pivoting the boom and tilting the bucket, with a pump, a reservoir, a control valve for adjusting the fluid connection between the pump, the reservoir and the driving element of the boom and with bucket valve means for controlling the fluid connection between the pump, the reservoir and the driving elements of the boom and the bucket, the bucket position being influenced in such a way that a desired alignment of the bucket when pivoting the Cantilever remains.
  • Load handling and vehicle handling devices such as industrial and agricultural loaders, often include leveling devices that control the direction of the bucket as the boom carrying the bucket is raised or lowered.
  • fluid can be supplied from the boom cylinder to the bucket cylinder.
  • liquid is supplied to the bucket cylinder from the pump or other sources.
  • the pump capacity must be increased unless higher cycle times are to be accepted.
  • Systems that rely solely on fluid from the boom cylinder can operate imprecisely because there is at times no back flow from the Boom cylinder is present or because the backflow changes due to changes in the load pressure or the number of working cycles.
  • Systems which derive the flow for the alignment of the bucket from a secondary cylinder require a very careful adjustment of the secondary cylinder stroke volume to the geometry and the stroke volume of the bucket cylinder in the boom-bucket system.
  • the object is achieved by specifying a hydraulic control circuit according to the characterizing features of claim 1.
  • the control circuit controls the flow of liquid to the boom and bucket of a load handling device.
  • the hydraulic circuit contains a separate manually operated directional control valve for extending and retracting the boom and bucket cylinder.
  • the flow of liquid returning from the boom cylinder can be passed through a shuttle valve to the inlet opening of a blade alignment valve. Liquid that comes directly from the hydraulic pump can also be directed to this inlet opening.
  • Valves that react to pressure and are located in the supply line of the boom cylinder and between the pump and the inlet opening of the bucket alignment valve ensure an automatic and optional supply of the inlet opening of the bucket alignment valve with backflow from the boom cylinder, flow from the pump or flow from both, if necessary varying degrees.
  • the bucket alignment valve is actuated by solenoids which receive control signals from an electronic position feedback control unit. Last tere is connected to sensors for detecting the position of the boom and the bucket.
  • the blade alignment device 10 comprises a blade 12 which is pivotally attached to one end of a boom 14.
  • the boom 14 is attached at its other end to a frame part 16 of a vehicle or loader, not shown.
  • the boom 14 can be pivoted by a boom cylinder 18, and the bucket 12 can be pivoted by a bucket cylinder 20.
  • the bucket cylinder 20 is connected to the boom 14 and the bucket 12 by connecting members 11 and 13.
  • a hydraulic circuit 22 controls the fluid flow to and from the cylinders 18 and 20.
  • An electronic control circuit 28 receives a position signal from a boom position sensor 30 and a bucket position signal from a bucket position sensor 32.
  • the usual rotary potentiometers can serve as sensors 30 and 32.
  • the control unit 28 generates valve control signals which are applied to the input of an electrically actuable blade alignment valve 90 of the hydraulic circuit.
  • the control unit 28 can contain a conventional electronic analog control circuit for position feedback. This function can also be carried out by a digital control device which contains a suitable programmable computer.
  • the hydraulic circuit 22 contains a pump 40 and a sump or reservoir 42.
  • the pump 40 can supply the priority circuit, not shown, of the vehicle with pressurized liquid. It also supplies pressurized fluid via a priority valve 48 to a manually operable spring-centered 4-way, 4-position boom control valve 44 and to a manually-operated spring-centered 4-way, 3-position bucket control valve 46.
  • Valve 44 includes a pump opening, a reservoir opening, a first load opening, via line 52, pressure actuatable valve 54, and line 56 is connected to the head end of the boom cylinder 18, and a second load opening which is connected to the rod end of the cylinder 18 via the line 62, the pressure-actuated valve 64 and the line 66.
  • a shuttle valve 70 includes a bore 71, a first opening 72 which connects the bore 71 to the line 56, a second opening 74 which connects the bore 71 to the line 66, and a third opening 76 which the bore 71 to the Line 78 connects.
  • a valve member 80 with spherical ends is movably disposed in the bore 71 to close the openings 72, 74 at which the higher pressure is present and the opening 72, 74 at which the lower pressure is present with the opening 76 connect.
  • Valve 70 also includes a piston 82, one side of which is pressurized by line 62 and the other side of which is pressurized by the reservoir. High pressure in the line 62 moves the piston 82 and moves the valve part 80 according to FIG. 2 upwards.
  • the bucket control valve 46 includes a pump port, a reservoir port, a first load port that communicates with the top end of the bucket cylinder 20 via line 86, and a second load port that communicates with the rod end of the bucket cylinder 20 via line 88.
  • the hydraulic circuit 22 also contains a 4-way, 3-position vane alignment valve 90 which can be actuated by the solenoid coils 91 and 93.
  • the blade alignment valve 90 contains a reservoir opening which is connected to the reservoir 42 via the line 92 and the filter 94 and to the line 66 via the line 96 and the check valve 98.
  • the bucket alignment valve 90 further includes an inlet or pump opening, wel che can receive liquid from the pump 40 via the priority valve 48, the line 100, the pressure-actuated valve 102, the line 104 and the check valve 106.
  • the inlet or pump port also receives fluid from line 78 via check valve 108 and line 110.
  • Valve 90 also includes a first load port, which is connected via line 114 to the top of bucket cylinder 20 and line 86, and one second load opening, which is connected via line 116 to the rod end of the bucket cylinder 20 and the line 88.
  • the load pressure sensing lines 118, 120 and 122 communicate the pressure of the first load opening of the valve 90 (or via an inner load sensing passage of the second load opening of the valve 90) to the pressure actuable valve 54, 64 and 102, respectively.
  • Another load sensing line 121 may be used if this system is to be used in a hydraulic system that includes pumps or pressure and flow compensation control valves.
  • the pressure actuatable valve 54 is usually held in the closed position by the spring 124 and the pressure in the line 118. It is opened via the control lines 53 and 57 by pressure in the lines 52 and 56.
  • the pressure actuatable valve 64 is usually kept closed by the spring 126 and the pressure in the line 120. It is opened when there is pressure in the lines 62 and 66, which is communicated by the control lines 140 and 142, respectively.
  • the pressure actuatable valve 102 is kept open by the spring 128 and the pressure in the line 122. Pressure in line 130 closes valve 102 against the combined forces that result from spring 128 and the pressure in line 122 and counteract the pressure in line 130.
  • Lowering of the bucket 12 due to leakage can be accomplished by adding a controlled check valve 123 can be reduced in line 114.
  • the control line 125 supplies pump pressure to open the valve 123 when the bucket cylinder 20 is to be lowered.
  • the position sensors 30 and 32, the electronic control circuit 28 and the bucket alignment valve 90 cooperate to maintain the original alignment of the bucket 12 with respect to the frame 16.
  • valve 90 moves into its blade retraction position (a shift to the left according to FIG. 2) and the load pressure in the line 116 is also present via the pressure sensing line 118, 120 and 122 the Valves 54, 64 and 102 in connection.
  • This load pressure tends to close valves 54 and 64 and open valve 102.
  • liquid is available at the rod end of the cylinder 20, namely from the pump 40 via the valve 48, the line 100, the valve 102 and the line 104 and / or from the rod end of the cylinder 18 via the line 66, the valve 70 Line 78, valve 108 and line 110.
  • valve 102 closes at a lower pressure differential than valve 64, so valve 102 closes and blocks flow from pump 40 when there is sufficient backflow from cylinder 18 and there is sufficient pressure in line 66 to achieve the desired retraction of cylinder 20 via valve 90. If for some reason little or no oil flows back from the rod end of the cylinder 18, the valve 64 is closed and the valve 102 remains open to deliver fluid from the pump 40 to the valve 90.
  • the control valve 44 is preferably designed such that, when the slide is moved in the direction of retraction of the boom cylinder 18, the line 52 is connected to the reservoir 42 before the line 62 is applied to the pump pressure. Gravity tends to lower the boom 14 and pressurize the head end of the boom cylinder 18. This pressure causes the valve 54 to open through the lines 56 and 57, as a result of which a backflow through the line 52 and the valve 44 is possible and the boom 14 can lower. At the same time, the expanding rod end of the cylinder 18 receives fluid from the reservoir 42 through line 66, check valve 98, lines 96 and 92, and filter 94.
  • Sensors 30 and 32, electronic control circuit 28, and bucket alignment valve 90 cooperate to extend cylinder 20 and maintain the required position of bucket 12 with respect to frame 16 when boom 14 is lowered.
  • the valve 90 is moved into its bucket cylinder extended position (according to FIG. 2 there is a shift to the right).
  • the fluid pressure in line 114 corresponding to the bucket load is sensed and applied to valves 54, 64 and 102.
  • the piston 82 in the valve 70 is pressurized via the valve 44, the line 62 and the control line 140.
  • the valve 70 shifts when the pressure in the line 62 is approximately one third of the pressure in the head end of the cylinder 18 is in a position in which the opening 74 is closed and the opening 72 communicates with the opening 76 so that a backflow from the head end of the cylinder 18 through the line 78, the valve 108, the lines 110 and 104 and the check valve 106 can take place to the valve 90. This backflow then becomes the main source for extending the bucket cylinder 20.
  • valve 90 If the supply of liquid in line 100 exceeds the value required to hold the bucket 12 in position via valve 90, the pressure in line 62 causes valve 64 to open, causing the excess liquid to Rod end of the boom cylinder 18 can flow. If the pressure in the rod end of the boom cylinder 18 and in the control line 130 increases over the sum of the forces resulting from the spring 128 and the pressure in the line 122, the valve 102 closes and drives the entire flow from the pump 40 the rod end of the cylinder 18, causing the cycle time to decrease takes. The excess flow volume in line 56 generated by the required bucket cylinder expansion flows through valve 54, line 52 and valve 44 to collecting container 42.
  • the present invention can be applied to a boom-and-vane cylinder assembly as disclosed in U.S. Patent No. 4,408,518 by exchanging connections to solenoids 91 and 93 such that the boom and bucket cylinders extend and retract together .
  • the blade position sensor can be arranged in a better protected location, for example between the blade cylinder housing and a connecting member 11. This requires that the electronic control circuit be modified to derive the boom-to-bucket relationship from the relationship between the cylinder 20 and the link 11.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Operation Control Of Excavators (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Servomotors (AREA)
  • Supplying Of Containers To The Packaging Station (AREA)
  • Forklifts And Lifting Vehicles (AREA)
EP89109918A 1988-06-06 1989-06-01 Dispositif pour la conservation de l'assiette d'un outil porté par des chargeurs Expired - Lifetime EP0345640B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US202286 1988-06-06
US07/202,286 US4923362A (en) 1988-06-06 1988-06-06 Bucket leveling system with dual fluid supply

Publications (2)

Publication Number Publication Date
EP0345640A1 true EP0345640A1 (fr) 1989-12-13
EP0345640B1 EP0345640B1 (fr) 1992-04-29

Family

ID=22749250

Family Applications (1)

Application Number Title Priority Date Filing Date
EP89109918A Expired - Lifetime EP0345640B1 (fr) 1988-06-06 1989-06-01 Dispositif pour la conservation de l'assiette d'un outil porté par des chargeurs

Country Status (8)

Country Link
US (1) US4923362A (fr)
EP (1) EP0345640B1 (fr)
AU (1) AU608712B2 (fr)
CA (1) CA1308073C (fr)
DE (1) DE58901263D1 (fr)
HU (1) HU205323B (fr)
NO (1) NO169503C (fr)
ZA (1) ZA894274B (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2683867A1 (fr) * 1991-10-28 1993-05-21 Danfoss As Circuit hydraulique pour le fonctionnement synchrone de deux verins double effet, notamment pour chargeuse pelleteuse.
EP2067911A4 (fr) * 2006-09-30 2013-05-01 Sany Heavy Ind Co Ltd Procédé et appareil destinés à supprimer la vibration d'un bras d'un véhicule à pompe à béton

Families Citing this family (29)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0791842B2 (ja) * 1988-01-18 1995-10-09 株式会社小松製作所 バケットレベラ装置
US5160239A (en) * 1988-09-08 1992-11-03 Caterpillar Inc. Coordinated control for a work implement
USRE34292E (en) * 1990-02-16 1993-06-22 Sunbelt Automated Systems, Inc. Refuse collection and loading system
US5049026A (en) * 1990-02-16 1991-09-17 Sunbelt Automated Systems, Inc. Refuse collection and loading system
US5192179A (en) * 1991-05-24 1993-03-09 Geza Kovacs Lift arm and tilt linkage systems for load elevating vehicles
US5447094A (en) * 1994-02-07 1995-09-05 Delta Power Hydraulic Co. Hydraulic system for bucket self-leveling during raising and lowering of boom
US5797310A (en) * 1997-01-29 1998-08-25 Eaton Corporation Dual self level valve
US6390312B1 (en) * 1998-02-27 2002-05-21 Jlg Industries, Inc. Lift structures and lifting arrangement therefor
US6116846A (en) * 1998-04-20 2000-09-12 Bulkley; Neil Front end loader assembly for a vehicle
US6129155A (en) * 1998-12-02 2000-10-10 Caterpillar Inc. Method and apparatus for controlling a work implement having multiple degrees of freedom
JP3923242B2 (ja) * 2000-07-14 2007-05-30 株式会社小松製作所 油圧駆動機械のアクチュエータ制御装置
AU2001294901A1 (en) * 2000-10-03 2002-04-15 Husco International, Inc. Two-way, self-level valve
FR2827320B1 (fr) * 2001-05-15 2003-10-10 Faucheux Ind Soc Dispositif chargeur programmable
US6647718B2 (en) * 2001-10-04 2003-11-18 Husco International, Inc. Electronically controlled hydraulic system for lowering a boom in an emergency
US6895319B2 (en) * 2003-03-07 2005-05-17 Deere & Company Valve command signal processing system
US6757994B1 (en) * 2003-04-11 2004-07-06 Deere & Company Automatic tool orientation control for backhoe with extendable dipperstick
ITBO20030374A1 (it) * 2003-06-19 2004-12-20 Ima Spa Metodo e struttura per la copertura di una macchina confezionatrice.
US7040044B2 (en) * 2003-12-15 2006-05-09 Caterpillar S.A.R.L. Method of modulating a boom assembly to perform in a linear manner
US7093383B2 (en) * 2004-03-26 2006-08-22 Husco International Inc. Automatic hydraulic load leveling system for a work vehicle
EP1954888A1 (fr) * 2005-11-10 2008-08-13 Volvo Construction Equipment AB Chargeuse
FI123932B (fi) 2006-08-16 2013-12-31 John Deere Forestry Oy Puomirakenteen ja siihen nivelletysti kiinnitetyn työkalun ohjaus
DE102009028816A1 (de) * 2009-08-21 2011-02-24 Deere & Company, Moline Hydraulische Anordnung
US8463508B2 (en) * 2009-12-18 2013-06-11 Caterpillar Inc. Implement angle correction system and associated loader
WO2014054983A1 (fr) * 2012-10-03 2014-04-10 Volvo Construction Equipment Ab Agencement de levage pour un engin de travail
US8862340B2 (en) 2012-12-20 2014-10-14 Caterpillar Forest Products, Inc. Linkage end effecter tracking mechanism for slopes
US9394929B2 (en) 2013-08-01 2016-07-19 Caterpillar Inc. Reducing dig force in hydraulic implements
EP3507422B1 (fr) * 2016-08-30 2021-05-26 Clark Equipment Company Dispositif de levage de puissance
US11168712B2 (en) 2019-02-22 2021-11-09 Clark Equipment Company Hydraulic leveling circuit for power machines
CN115095567A (zh) * 2022-07-28 2022-09-23 徐州徐工矿业机械有限公司 用于正铲液压挖掘机调平油缸的液压系统及控制方法

Citations (6)

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Publication number Priority date Publication date Assignee Title
DE1122443B (de) * 1960-02-01 1962-01-18 Meiller Fahrzeuge Anordnung zur Steuerung der Hub- und Wippbewegung einer Ladeschaufel an einem Frontlader
US3179120A (en) * 1963-05-24 1965-04-20 Koehring Co Proportional flow divider
GB1206607A (en) * 1966-10-21 1970-09-23 Caterpillar Tractor Co Hydraulic control circuit
US3987920A (en) * 1975-06-23 1976-10-26 J. I. Case Company Self-leveling system for material handling implement
GB1599283A (en) * 1978-05-24 1981-09-30 Hayward J A D Linkages for raising and lowering loads/materials
WO1988001600A1 (fr) * 1986-09-01 1988-03-10 Ösa Ab Dispositif servant a maintenir le dispositif de fixation de l'outil d'une grue a bras d'articulation a un niveau constant au-dessus du sol

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US3251277A (en) * 1964-04-23 1966-05-17 Parker Hannifin Corp Fluid system and valve assembly therefor
US3563137A (en) * 1969-06-30 1971-02-16 Cessna Aircraft Co Hydraulic self-leveling control for boom and bucket
US3811587A (en) * 1972-07-17 1974-05-21 Case Co J I Hydraulic leveling circuit for implement
DE2834480C2 (de) * 1978-08-05 1986-01-02 Baas Technik GmbH, 2000 Wedel Steuereinrichtung eines Schaufelladers od.dgl.
US4408518A (en) * 1981-03-17 1983-10-11 The Cessna Aircraft Company Series self-leveling valve
US4375344A (en) * 1981-07-02 1983-03-01 J. I. Case Company Bucket leveling mechanism
US4561342A (en) * 1983-07-25 1985-12-31 The Cessna Aircraft Company Series self-leveling valve
US4664017A (en) * 1984-03-19 1987-05-12 General Signal Corporation Hydraulic control system and valve

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1122443B (de) * 1960-02-01 1962-01-18 Meiller Fahrzeuge Anordnung zur Steuerung der Hub- und Wippbewegung einer Ladeschaufel an einem Frontlader
US3179120A (en) * 1963-05-24 1965-04-20 Koehring Co Proportional flow divider
GB1206607A (en) * 1966-10-21 1970-09-23 Caterpillar Tractor Co Hydraulic control circuit
US3987920A (en) * 1975-06-23 1976-10-26 J. I. Case Company Self-leveling system for material handling implement
GB1599283A (en) * 1978-05-24 1981-09-30 Hayward J A D Linkages for raising and lowering loads/materials
WO1988001600A1 (fr) * 1986-09-01 1988-03-10 Ösa Ab Dispositif servant a maintenir le dispositif de fixation de l'outil d'une grue a bras d'articulation a un niveau constant au-dessus du sol

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN, Band 9, Nr. 294 (M-431)[2017], 20. November 1985; & JP-A-60 133 127 (HITACHI KENKI K.K.) 16-07-1985 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2683867A1 (fr) * 1991-10-28 1993-05-21 Danfoss As Circuit hydraulique pour le fonctionnement synchrone de deux verins double effet, notamment pour chargeuse pelleteuse.
EP2067911A4 (fr) * 2006-09-30 2013-05-01 Sany Heavy Ind Co Ltd Procédé et appareil destinés à supprimer la vibration d'un bras d'un véhicule à pompe à béton

Also Published As

Publication number Publication date
AU3601189A (en) 1989-12-07
HU205323B (en) 1992-04-28
NO892217L (no) 1989-12-07
NO169503C (no) 1992-07-01
HUT51569A (en) 1990-05-28
ZA894274B (en) 1991-02-27
AU608712B2 (en) 1991-04-11
CA1308073C (fr) 1992-09-29
US4923362A (en) 1990-05-08
NO169503B (no) 1992-03-23
DE58901263D1 (de) 1992-06-04
NO892217D0 (no) 1989-06-01
EP0345640B1 (fr) 1992-04-29

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