EP2772653A1 - Système de commande pour faire fonctionner un dispositif de travail d'une machine de construction - Google Patents

Système de commande pour faire fonctionner un dispositif de travail d'une machine de construction Download PDF

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Publication number
EP2772653A1
EP2772653A1 EP11873593.5A EP11873593A EP2772653A1 EP 2772653 A1 EP2772653 A1 EP 2772653A1 EP 11873593 A EP11873593 A EP 11873593A EP 2772653 A1 EP2772653 A1 EP 2772653A1
Authority
EP
European Patent Office
Prior art keywords
control valve
boom
control
flow path
center bypass
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.)
Withdrawn
Application number
EP11873593.5A
Other languages
German (de)
English (en)
Other versions
EP2772653A4 (fr
Inventor
Hea-Gyoon Joung
Young-Bog SONG
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.)
Volvo Construction Equipment AB
Original Assignee
Volvo Construction Equipment 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 Volvo Construction Equipment AB filed Critical Volvo Construction Equipment AB
Publication of EP2772653A1 publication Critical patent/EP2772653A1/fr
Publication of EP2772653A4 publication Critical patent/EP2772653A4/fr
Withdrawn legal-status Critical Current

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Classifications

    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2278Hydraulic circuits
    • E02F9/2282Systems using center bypass type changeover valves
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F3/00Dredgers; Soil-shifting machines
    • E02F3/04Dredgers; Soil-shifting machines mechanically-driven
    • E02F3/28Dredgers; 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
    • E02F3/36Component parts
    • E02F3/42Drives for dippers, buckets, dipper-arms or bucket-arms
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/08Superstructures; Supports for superstructures
    • E02F9/10Supports for movable superstructures mounted on travelling or walking gears or on other superstructures
    • E02F9/12Slewing or traversing gears
    • E02F9/121Turntables, i.e. structure rotatable about 360°
    • E02F9/123Drives or control devices specially adapted therefor
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2217Hydraulic or pneumatic drives with energy recovery arrangements, e.g. using accumulators, flywheels
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2221Control of flow rate; Load sensing arrangements
    • E02F9/2225Control of flow rate; Load sensing arrangements using pressure-compensating valves
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2264Arrangements or adaptations of elements for hydraulic drives
    • E02F9/2267Valves or distributors
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2278Hydraulic circuits
    • E02F9/2285Pilot-operated systems
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2278Hydraulic circuits
    • E02F9/2292Systems with two or more pumps
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/16Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • F15B11/17Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors using two or more pumps
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/20Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205Systems with pumps
    • F15B2211/2053Type of pump
    • F15B2211/20546Type of pump variable capacity
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/20Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205Systems with pumps
    • F15B2211/20576Systems with pumps with multiple pumps
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/30Directional control
    • F15B2211/31Directional control characterised by the positions of the valve element
    • F15B2211/3105Neutral or centre positions
    • F15B2211/3116Neutral or centre positions the pump port being open in the centre position, e.g. so-called open centre
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/30Directional control
    • F15B2211/31Directional control characterised by the positions of the valve element
    • F15B2211/3122Special positions other than the pump port being connected to working ports or the working ports being connected to the return line
    • F15B2211/3133Regenerative position connecting the working ports or connecting the working ports to the pump, e.g. for high-speed approach stroke

Definitions

  • the present invention relates to an attachment driving control system for a construction machine. More particularly, the present invention relates to an attachment driving control system for a construction machine, in which in the case where two attachments having different operating pressures are simultaneously driven (e.g., the case where a boom for performing a boom descending operation and an attachment such as a bucket are simultaneously driven), a flow rate of a hydraulic fluid is controlled to enable the simultaneous use of a parallel flow path and a tandem flow path, leading to a reduction in a pressure loss occurring in the control valve.
  • two attachments having different operating pressures e.g., the case where a boom for performing a boom descending operation and an attachment such as a bucket are simultaneously driven
  • a flow rate of a hydraulic fluid is controlled to enable the simultaneous use of a parallel flow path and a tandem flow path, leading to a reduction in a pressure loss occurring in the control valve.
  • a conventional boom driving control system for a construction machine in accordance with the prior art as shown in Fig. 1 includes:
  • the boom control valve 14 is shifted to the right on the drawing sheet to cause the boom to descend, and thus the hydraulic fluid discharged from the second hydraulic pump 3 is supplied to the small chamber of the boom cylinder 13 via the boom control valve 14.
  • the hydraulic fluid flowing out of the large chamber of the boom cylinder 13 returns to the hydraulic tank T via the boom control valve 14 and a back pressure check valve 23.
  • the boom cylinder 13 can be driven in a retractable manner to cause the boom to descend.
  • the back pressure check valve 23 is mounted with a valve spring so that when a hydraulic fluid passes therethrough, a constant pressure is formed.
  • a regeneration line is installed in the back pressure check valve 23 so that the hydraulic fluid flowing out of the large chamber of the boom cylinder 13 can be regenerated to the small chamber of boom cylinder 13 along the regeneration line during the descending of the boom.
  • a lower pressure acts on the boom due to the descending operation by its own weight.
  • a throttle device is installed at a hydraulic fluid inlet side of a control spool (i.e., referring to the boom control valve 14) on a boom descending side so that simultaneous manipulability of the boom and the bucket can be maintained.
  • a throttle device is installed in the parallel flow path of each attachment that is operated at a relatively low pressure to produce a pressure causing the boom to ascend so that simultaneous manipulability of the boom for performing a boom ascending operation and another attachment can be implemented.
  • a tandem flow path is formed in the bucket control valve 16 and the traveling control valve 18 which are connected in parallel with the boom control valve 14 through the second center bypass path 12. That is, in the case where the drive of the bucket cylinder 15 is controlled alone, the hydraulic fluid from the second hydraulic pump 3 flows into the bucket control valve 16 through the parallel flow path 12a and the tandem flow path, thereby reducing an excessive pressure loss occurring when the hydraulic fluid from the second hydraulic pump 3 flows into the bucket control valve 16 through only the parallel flow path 12a.
  • the second center bypass path 12 is blocked by the control spool on a boom descending side and the hydraulic fluid is supplied to the bucket cylinder 15 through only the parallel flow path 12a.
  • a sufficient flow path cannot be secured by a priority control valve installed in the parallel flow path 12a, thereby inducing an excessive pressure loss, and thus causing an energy loss.
  • variable control valve as a throttle valve 24 (see Fig. 2 ) may be installed in the parallel flow path 12a, but there is a limitation in securing the flow path using the throttle device.
  • the present invention has been made to solve the aforementioned problem occurring in the prior art, and it is an object of the present invention to provide an attachment driving control system for a construction machine, in which in the case where two attachments having different operating pressures are simultaneously driven as in a boom descending operation and a bucket operation, a hydraulic fluid from the second hydraulic pump is allowed to flow into the bucket control valve through a parallel flow path and a tandem flow path, leading to a reduction in an unnecessary pressure loss occurring in the control valve, thereby reducing an energy loss and thus increasing an efficiency of a hydraulic system.
  • an attachment driving control system for a construction machine in accordance with an embodiment of the present invention, including:
  • the attachment is a bucket
  • the control valve that controls the attachment is the bucket control valve
  • the attachment driving control system for a construction machine in accordance with an embodiment of the present invention as constructed above has the following advantages.
  • a hydraulic fluid from the second hydraulic pump is allowed to flow into the bucket control valve through the parallel flow path and the tandem flow path (i.e., in this case, a flow path can secured as much as a flow rate of the hydraulic fluid passing through the tandem flow path), leading to a reduction in a pressure loss occurring in the control valve, thereby reducing an energy loss.
  • An attachment driving control system for a construction machine in accordance with an embodiment of the present invention as shown in Figs. 3 and 4 includes:
  • a hydraulic fluid from the second hydraulic pump 3 flows into the bucket control valve 16 through the parallel flow path 12a and a tandem flow path connected to the second center bypass path 12 when a boom for performing a boom descending operation and an attachment (i.e., referring to a bucket) having an operating pressure relatively higher than that of the boom are simultaneously driven.
  • the configuration of the attachment driving control system shown in Fig. 1 is the same as that of the attachment driving control system shown in Fig. 1 except the bleed flow path 25 that is formed on a control spool on a boom descending side of the boom control valve 14a and maintains the second center bypass path 12 in an opened state instead of blocking the second center bypass path 12 when the boom control valve 14a is shifted to descend the boom through the manipulation of the pressure generation device 19, and the center bypass shift valve 26 that is installed on the lowermost downstream side of the second center bypass path 12 and is shifted by a control signal pressure for shifting the boom control valve 14a.
  • the same configuration and operation thereof will be omitted to avoid redundancy, and the same elements are denoted by the same reference numerals.
  • the boom control valve 14a is shifted to the right on the drawing sheet in response to a pilot signal pressure from the pilot pump 4, which passes through the pressure generation device 19, by the manipulation of the pressure generation device 19.
  • a hydraulic fluid discharged from the second hydraulic pump 3 is supplied to a small chamber of the boom cylinder 13 via a load check valve 22 and the boom control valve 14a.
  • a hydraulic fluid flowing out of a large chamber of the boom cylinder 13 returns to a hydraulic tank T via the boom control valve 14a and a back pressure check valve 23.
  • the boom cylinder 13 is driven in a retractable manner to cause the boom to descend.
  • the hydraulic fluid flowing out of the large chamber of the boom cylinder 13 is partially regenerated to the small chamber of the boom cylinder 13 through a regeneration line formed on a control spool (i.e., referring to the boom control valve 14a) on a boom descending side.
  • the hydraulic fluid discharged from the second hydraulic pump 3 is supplied to an inlet side of the bucket control valve 16 via the second center bypass path 12 and the bleed flow path 25 formed on a control spool on a boom descending side of the boom control valve 14a.
  • the bleed flow path 25 is connected to a spool path of the bucket control valve 16 via a load check valve 27 of the bucket control valve 16.
  • a hydraulic fluid passing through a priority control valve installed on a parallel flow path 12a joins a hydraulic fluid passing through the load check valve 27, and then flows into a spool of the bucket control valve 16.
  • the attachment driving control system for a construction machine in accordance with an embodiment of the present invention is advantageous in that in the case where two attachments having different operating pressures are simultaneously driven as in a boom descending operation and a bucket operation, a hydraulic fluid from the second hydraulic pump is allowed to flow into the bucket control valve through the parallel flow path and the tandem flow path, leading to a reduction in a pressure loss occurring in the control valve, thereby increasing energy efficiency of the hydraulic system.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Operation Control Of Excavators (AREA)
  • Fluid-Pressure Circuits (AREA)
EP11873593.5A 2011-10-07 2011-10-07 Système de commande pour faire fonctionner un dispositif de travail d'une machine de construction Withdrawn EP2772653A4 (fr)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/KR2011/007439 WO2013051740A1 (fr) 2011-10-07 2011-10-07 Système de commande pour faire fonctionner un dispositif de travail d'une machine de construction

Publications (2)

Publication Number Publication Date
EP2772653A1 true EP2772653A1 (fr) 2014-09-03
EP2772653A4 EP2772653A4 (fr) 2015-10-21

Family

ID=48043892

Family Applications (1)

Application Number Title Priority Date Filing Date
EP11873593.5A Withdrawn EP2772653A4 (fr) 2011-10-07 2011-10-07 Système de commande pour faire fonctionner un dispositif de travail d'une machine de construction

Country Status (6)

Country Link
US (1) US20140238010A1 (fr)
EP (1) EP2772653A4 (fr)
JP (1) JP5802338B2 (fr)
KR (1) KR20140074306A (fr)
CN (1) CN103842663A (fr)
WO (1) WO2013051740A1 (fr)

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101861856B1 (ko) * 2012-01-27 2018-05-28 두산인프라코어 주식회사 건설기계의 스윙 모터 유압제어장치
WO2014112668A1 (fr) 2013-01-18 2014-07-24 볼보 컨스트럭션 이큅먼트 에이비 Dispositif de régulation de flux et procédé de régulation de flux de machine de construction
EP2960529B1 (fr) 2013-02-19 2019-01-02 Volvo Construction Equipment AB Système hydraulique destiné à un engin de construction, muni d'un dispositif de protection
KR20160023710A (ko) 2013-06-28 2016-03-03 볼보 컨스트럭션 이큅먼트 에이비 플로팅기능을 갖는 건설기계용 유압회로 및 플로팅기능 제어방법
EP3026181B1 (fr) * 2013-07-24 2018-11-14 Volvo Construction Equipment AB Circuit hydraulique pour engin de chantier
CN104179738B (zh) * 2014-08-07 2016-04-13 龙工(上海)精工液压有限公司 一种滑移装载机开式液压系统
EP3196367B1 (fr) * 2014-09-19 2022-04-13 Volvo Construction Equipment AB Circuit hydraulique pour engin de chantier
WO2016098926A1 (fr) * 2014-12-17 2016-06-23 볼보 컨스트럭션 이큅먼트 에이비 Procédé de commande pour entraîner un actionneur hydraulique d'un engin de chantier
WO2016208780A1 (fr) * 2015-06-22 2016-12-29 볼보 컨스트럭션 이큅먼트 에이비 Circuit hydraulique pour engin de chantier
JP7198072B2 (ja) * 2018-12-13 2022-12-28 キャタピラー エス エー アール エル 建設機械の油圧制御回路
JP7221101B2 (ja) * 2019-03-20 2023-02-13 日立建機株式会社 油圧ショベル
JP7305532B2 (ja) * 2019-12-28 2023-07-10 株式会社クボタ 流量制御弁

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Also Published As

Publication number Publication date
JP5802338B2 (ja) 2015-10-28
JP2014534386A (ja) 2014-12-18
EP2772653A4 (fr) 2015-10-21
WO2013051740A1 (fr) 2013-04-11
KR20140074306A (ko) 2014-06-17
US20140238010A1 (en) 2014-08-28
CN103842663A (zh) 2014-06-04

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