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US3478647A - Circuit for hydraulically operable devices,especially hydraulic dredges - Google Patents

Circuit for hydraulically operable devices,especially hydraulic dredges Download PDF

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Publication number
US3478647A
US3478647A US712189A US3478647DA US3478647A US 3478647 A US3478647 A US 3478647A US 712189 A US712189 A US 712189A US 3478647D A US3478647D A US 3478647DA US 3478647 A US3478647 A US 3478647A
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US
United States
Prior art keywords
valve
control
pump
valves
oil
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
US712189A
Other languages
English (en)
Inventor
Jurgen Gerber
Friedrich Fichtner
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.)
Orenstein Koppel und Luebecker Maschinenbau AG
CNH Industrial Baumaschinen GmbH
Original Assignee
O&K Orenstein and Koppel GmbH
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 O&K Orenstein and Koppel GmbH filed Critical O&K Orenstein and Koppel GmbH
Application granted granted Critical
Publication of US3478647A publication Critical patent/US3478647A/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
    • E02F9/2221—Control of flow rate; Load sensing arrangements
    • 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
    • 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
    • F15B11/17—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors using two or more 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
    • F15B2211/20—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
    • 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
    • F15B2211/31—Directional control characterised by the positions of the valve element
    • F15B2211/3105—Neutral or centre positions
    • F15B2211/3116—Neutral or centre positions the pump port being open in the centre position, e.g. so-called open 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
    • F15B2211/70—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
    • F15B2211/705—Output members, e.g. hydraulic motors or cylinders or control therefor characterised by the type of output members or actuators
    • F15B2211/7058—Rotary 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
    • F15B2211/7142—Multiple output members, e.g. multiple hydraulic motors or cylinders the output members being arranged in multiple groups

Definitions

  • FIGURE 1 represents a control circuit according to the present invention
  • FIGURE 2 is a partial longitudinal section through a control valve with the particular guiding means for the control oil according to the present invention.
  • FIGURE 3 is a partial section through a control valve preceded by an auxiliary control valve.
  • control conduits which control the pressureless circulation of the pumps (1, 2) and are provided with check valves are after the passage through the precontrolled pressure limiting valves combined with the control valves associated with the driving 3,478,647 Patented Nov. 18, 1969 "ice mechanisms and the swinging mechanisms so as to form a common control conduit which latter after passing through the control valves which are associated with the Working devices will in idling condition of the circuit return the control oil to an oil reservoir whereas when actuating one control valve or a plurality of control valves the delivery to the oil reservoir will be blocked.
  • control of the control oil is effected through the intervention of an auxiliary piston which is displaceably arranged in a control bushing which axially precedes the control housing of the control valve and simultaneously serves as housing.
  • the pumps 1 and 2 produce the pressure oil for actuating the right and left driving mechanisms 3, 4 when the dredge is equipped with a track-laying drive.
  • the pumps 1 and 2 furthermore produce the pressure oil for actuating the swinging mechanism 5 and the cylinders 6, 7 and 8 for respectively actuating the boom, the dipper arm and the digging vessel or bucket of the dredge.
  • the two driving mechanisms 3 and 4 and the swinging mechanism 5 receive the pressure oil through control valves 9, 10 and 11.
  • the cylinders 6, 7 and 8 receive the pressure oil for actuating the same through associated control valves 12, 13 and 14.
  • Pump 1 has associated therewith a relief valve 16 from where the control oil, in case no consumers are to be actuated, passes through the check valve 17, the valves 9 and 11, and the control conduit 18 whereas the control oil from the relief valve 15 passes through the check valve 19, control valve 10 and control conduit 20.
  • the two control conduits 18 and 20 unite so as to form the control conduit 21.
  • the relief valves 15 and 16 each have a leakage return oil line or conduit 15' and 16', respectively, associated therewith as represented by dotted lines in FIG, 1.
  • the combination or separation of the delivery of the said two pumps 1 and 2 for actuating either one or more of the three working cylinders 6, 7 and 8 is effected in the following manner:
  • the control va ve 12 for the working cylinder 6, or more specifically, the valve spool of control valve 12 is from its neutral position moved toward the right or the left, the two control conduits 18 and 20 which have been united to the control conduit 21 are blocked.
  • the circulation of both .pumps 1 and 2 is blocked by the relief valves 15 and 16,
  • control valve 14 When now, for instance, the control valve 14 is additionally actuated by moving the same from its neutral position toward the right or toward the left, the passage of the oil under pressure delivered by the pump 2 from conduit 30 to conduit 31 is interrupted so that the delivery of pump 2 now passes through conduit 34 to the working cylinder 8.
  • This combination possibility also applies to the flow between control valves 13 and 14 and the flow between control valves 12 and 13.
  • check valves 17 and 19 are respectively arranged in the control conduits 18 and 20.
  • FIG. 2 shows in greater detail the passages in a control valve, for instance the control valve 12-
  • the valve spool 36 is reciprocable in the control valve housing 35.
  • the housing 35 has pressed thereinto a bushing 37 which comprises one or more nozz e bores 38.
  • the valve spool 36 is actuated, in any con venient manner, for instance, hydraulically or mechanically, the nozzle bores 38 are first throttled by the inclined surfaces 39 and are subsequently shut off by control edge 40 or 41, respectively.
  • control oil flow which enters the control valve 12 through bore 42 can be throttled in an Moe sensitive manner in order to be able in the precontrolled relief valves 15 and 16 to effect the division of the delivered oil flow in conformity with the requirements for the fine control of the consumer.
  • control housing for instance, of the control valve 13 has screwed thereonto an intermediate housing. 43 in which an auxiliary valve spool 44 is displaceable mounted, Valve spool 44 rests by means of a spring dish 45 and spring 46 against the cover 47.
  • the nozzle bores 48, the inclined surfaces 49, and the edges 50 have the same function as that of the respective members 38, 39 and 40 described above in connection with FIG. 2.
  • the actuation of the main valve spool 36 in one direction is in the particular embodiment illustrated in the drawing effected by hydraulic control through the connection 51.
  • the arrangement according to the present invention affords the possibility, without resorting to electrical or mechanical coupling members, in a purely hydraulic manner to combine any desired number of pump circuits of a corresponding number of consumers in any desired manner.
  • two out of four consumers will obtain the oil of all pumps if only one of said pump circuits is actuated, whereas a third consumer may be delivered only with the oil from two pumps anl the oil of the third pump will be available to the fourth or other consumers.
  • valve to cause a supply of fluid to the right-hand driving mechanism 4 will interrupt the connection of pump 2 to conduit 28 and will also interrupt the connection of check valve 19 with conduit 20. Pump 2 will thus deliver fluid solely to driving mechanism 4 only. Pump 1, at this time may continue to bypass to tank 25 via check valve 17 and conduits 18 and 21.
  • valve 9 Similarly, shifting of valve 9 will cause pump 1 to deliver solely to left-hand driving mechanism 3, or shifting of valve 11 will cause pump 1 to deliver solely to swing mechanism 5.
  • Valve 11 is effective only if valve 9 is not shifted. It will be seen that driving mechanisms 3 and 4 can be operated either independently or simultaneously but when both thereof are driven no other device can be actuated. Mechanism 5 can be actuated only when mechanism 3 is not actuated.
  • any one or two of cylinders 6, 7 and 8 can be actuated, If either one of pumps 1 or 2 is cut off from its conduit 26, 28 by actuation of one of the valves 9, 10, 11, then any one only of cylinders 6, 7, 8 can be actuated by pressure from the other of the pumps.
  • valve 13 In the case where none of valves 9, 10, 11 are shifted to supply their respective components, shifting of valve 13 will cause actuation of cylinder 7.
  • Pump 2 will supply valve 13 directly through conduits 28 and 29, whereas pump 1 will supp yvalve 13 via conduits 26, 26a, 31, check valve 31:: and conduits 31b and 29 so that the supply of both pumps is delivered to piston 7. If, while valve 13 is shifted, either one of valves 12 or 14 is shifted, the respective piston 6, 8, will be actuated by fluid from pump 1. At this time, pump 2 supplies piston 7 only, while. pump 1 supplies one only of pistons 6, 8.
  • valve 14 If, on the other hand, valve 14 is shifted to actuate piston 8, pump 2 will supply valve 14 via conduits 29 and 30 while pump 1 wi l also supply valve 14 via conduits 26 and 26a. It will be evident that a supply from one ofpumps 1, 2 to valve 14 will continue even if one or the other of valves 12, 13 is shifted to divert the supply of the other pu p- In still another case, if valve 12 is shifted, pump 1 will supply valve 12'directly while pump 2 will also supply valve 12 via conduits 29, 30, 31, check valve 32, and conduits 33 and 27; Shifting of either of valves 13 or 14 will cut off pump 2 from valve 12, while leaving pump l connected thereto, and will direct the fluid from pump 2 to the device pertaining to the shifted valve.
  • FIGURE 4 illustrates schematically valve 15.lIn FIG- URE 4, the line from the pump is indicated at 70, and the line back to'the reservoir is indicated at 72.
  • a valve mernber 74 is moveable upwardly to connect lines 70 and 72 when pump pressure becomes excessive, When valve 'mem-- ber 74 is in its FIGURE 4 position and all other valves are in neutral position, fluid passes from conduit 70 through restricted passage 76 to the lower side of valve 19 and therethrough. When a valve of the system is moved away from neutral position, fluid flow through valve 19 is interrupted.
  • a hydraulic control circuit especially for hydraulically actuated implements such as dredges and the like, comprising: pump means, a plurality of motor means to be actuated by pressure fluid from said pump means, control valve means for said motor means each having service port means connected to the'respective motor means and having pressure inlet port means and a movable valve member, each valve member having a first position wherein said service port means are disconnectedfrom said inlet port means and at least a second'position where-' in at least one of the-said service port means pertaining thereto is connected to said inlet port means, first bypass channel means leading from said pump means to exhaust and including a portion extending through each control valve means with said portions in series, second'channel' means leading from said pump means to the inlet port means of said control valve means and including a portion extending through each control valve means and interposed between the inlet port means of the respective control valve means and the inlet port means of the next following control valve means and with said portions in series, movement of any said valve members out of its said first position
  • said second channel means extending through the third one of said control valves being connected to both of said second channels, the portion of each said second channel leading from said third control valve to'the inlet port means of the next following control valve having a check valve therein opening away from said third con-- trol valve.
  • a hydraulic control circuit in which a further valve means is interposed between each said pump and the inlet of the pertaining control valve, each said second channel including a portion extending through said further valve means of the pertaining pump and each further valve means interrupting the said portion when shifted to cause the supply of fluid to a connected motor, said first channel means including a portion pertaining to each pump which extends through the pertaining further valve means and which portion is interrupted upon shifting of the valve means to supply fluid to a connected motor, said last mentioned portions of said first channel means being in parallel and each having a check valve therein opening away from the pertaining pump.
  • each control valve means has a housing in which the respective valve member is reciprocably mounted, said housing comprising a section having ports therein forming the inlet and outlet ends of the portion of said first channel means which extends therethrough, and auxiliary valve member means in said section and movable together with said first mentioned valve member and comprising an annular groove with inclined end portions, said groove registering with said ports in said section when said valve member is in its said first position and said inclined end portions throttling and then closing said ports as the valve member is shifted out of said first position thereof.
  • each said port in said section is in the form of at least one nozzle bore.

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  • 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)
US712189A 1967-03-10 1968-03-11 Circuit for hydraulically operable devices,especially hydraulic dredges Expired - Lifetime US3478647A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE1634915A DE1634915C3 (de) 1967-03-10 1967-03-10 Schaltung für Hydraulikbagger

Publications (1)

Publication Number Publication Date
US3478647A true US3478647A (en) 1969-11-18

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ID=7352746

Family Applications (1)

Application Number Title Priority Date Filing Date
US712189A Expired - Lifetime US3478647A (en) 1967-03-10 1968-03-11 Circuit for hydraulically operable devices,especially hydraulic dredges

Country Status (11)

Country Link
US (1) US3478647A (fr)
JP (1) JPS5345475B1 (fr)
AT (1) AT284018B (fr)
BE (1) BE711290A (fr)
CH (1) CH481279A (fr)
DE (1) DE1634915C3 (fr)
FI (1) FI47676C (fr)
FR (1) FR1555395A (fr)
GB (1) GB1222104A (fr)
NL (1) NL6802984A (fr)
SE (1) SE334129B (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3792836A (en) * 1972-03-06 1974-02-19 E Bender Simplified well rig
US4342254A (en) * 1973-12-22 1982-08-03 O & K Orenstein & Koppel Aktiengesellschaft Circuit for hydrostatically operable devices
FR2622936A1 (fr) * 1987-11-10 1989-05-12 Kubota Ltd Circuit hydraulique pour une pelle retrocaveuse
US5469797A (en) * 1994-02-07 1995-11-28 Hearne, Jr.; David C. Sugar cane planter
US6283488B1 (en) * 1997-10-08 2001-09-04 Gkn Walterscheid Gmbh Device for stabilizing the lower steering arms of a tractor
CN109944835A (zh) * 2019-04-02 2019-06-28 重庆平山矿山机电设备有限公司 一种钻机的液压系统及钻机

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5148231B2 (fr) * 1971-10-20 1976-12-20
BE792617A (fr) * 1971-12-13 1973-06-12 Caterpillar Tractor Co Circuit hydraulique pour un excavateur.
CA1278978C (fr) * 1987-02-19 1991-01-15 Lary Lynn Williams Systeme hydraulique pour machine industrielle
JPS63308821A (ja) * 1987-06-10 1988-12-16 Matsushita Electric Ind Co Ltd 可動形電子部品
JPH02101440U (fr) * 1989-01-27 1990-08-13
AU631727B2 (en) * 1990-03-09 1992-12-03 Kubota Corporation Hydraulic circuit for a working vehicle having a plurality of hydraulic actuators
DE4241846C2 (de) * 1992-12-11 1996-09-26 Danfoss As Hydraulisches System
DE19911440C2 (de) * 1999-03-04 2002-09-19 Komatsu Mining Germany Gmbh Vorrichtung und Verfahren zur Ansteuerung einer Hydraulikanlage einer Baumaschine, insbesondere eines Hydraulikbaggers
CN110482084B (zh) * 2019-08-20 2021-11-19 长沙中联重科环境产业有限公司 垃圾压实器
CN115853753B (zh) * 2022-12-22 2024-06-14 中国第一汽车股份有限公司 油泵卸荷系统、方法、存储介质和车辆

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2244213A (en) * 1939-01-12 1941-06-03 Hydraulic Control Engineering Valve structure
US2319551A (en) * 1937-08-09 1943-05-18 Fosdick Machine Tool Co Hydraulic operating and control mechanism for machine tools
US3146593A (en) * 1960-04-18 1964-09-01 Parker Hannifin Corp Dual pump system and control valve assembly therefor
US3156098A (en) * 1959-11-20 1964-11-10 Ford Motor Co Hydraulic power system

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2319551A (en) * 1937-08-09 1943-05-18 Fosdick Machine Tool Co Hydraulic operating and control mechanism for machine tools
US2244213A (en) * 1939-01-12 1941-06-03 Hydraulic Control Engineering Valve structure
US3156098A (en) * 1959-11-20 1964-11-10 Ford Motor Co Hydraulic power system
US3146593A (en) * 1960-04-18 1964-09-01 Parker Hannifin Corp Dual pump system and control valve assembly therefor

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3792836A (en) * 1972-03-06 1974-02-19 E Bender Simplified well rig
US4342254A (en) * 1973-12-22 1982-08-03 O & K Orenstein & Koppel Aktiengesellschaft Circuit for hydrostatically operable devices
FR2622936A1 (fr) * 1987-11-10 1989-05-12 Kubota Ltd Circuit hydraulique pour une pelle retrocaveuse
US5469797A (en) * 1994-02-07 1995-11-28 Hearne, Jr.; David C. Sugar cane planter
US6283488B1 (en) * 1997-10-08 2001-09-04 Gkn Walterscheid Gmbh Device for stabilizing the lower steering arms of a tractor
CN109944835A (zh) * 2019-04-02 2019-06-28 重庆平山矿山机电设备有限公司 一种钻机的液压系统及钻机
CN109944835B (zh) * 2019-04-02 2024-04-23 重庆平山机电设备有限公司 一种钻机的液压系统及钻机

Also Published As

Publication number Publication date
FI47676C (fi) 1974-02-11
AT284018B (de) 1970-08-25
SE334129B (fr) 1971-04-05
DE1634915A1 (de) 1970-10-29
DE1634915C3 (de) 1981-02-12
FR1555395A (fr) 1969-01-24
FI47676B (fr) 1973-10-31
JPS5345475B1 (fr) 1978-12-06
BE711290A (fr) 1968-07-01
GB1222104A (en) 1971-02-10
DE1634915B2 (de) 1977-09-08
CH481279A (de) 1969-11-15
NL6802984A (fr) 1968-09-11

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