KR100813779B1 - boom control device in an excavator - Google Patents

boom control device in an excavator Download PDF

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Publication number
KR100813779B1
KR100813779B1 KR1020010088811A KR20010088811A KR100813779B1 KR 100813779 B1 KR100813779 B1 KR 100813779B1 KR 1020010088811 A KR1020010088811 A KR 1020010088811A KR 20010088811 A KR20010088811 A KR 20010088811A KR 100813779 B1 KR100813779 B1 KR 100813779B1
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South Korea
Prior art keywords
boom
hydraulic
valve
control valve
pilot
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KR1020010088811A
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Korean (ko)
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KR20030058384A (en
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권성준
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두산인프라코어 주식회사
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    • 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
    • E02F9/226—Safety arrangements, e.g. hydraulic driven fans, preventing cavitation, leakage, overheating
    • 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
    • E02F3/435—Control of dipper or bucket position; Control of sequence of drive operations for dipper-arms, backhoes or the like
    • 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
    • E02F9/2264—Arrangements or adaptations of elements for hydraulic drives
    • E02F9/2267—Valves or distributors
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E02F9/2278—Hydraulic circuits
    • E02F9/2285—Pilot-operated systems

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  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Operation Control Of Excavators (AREA)
  • Component Parts Of Construction Machinery (AREA)
  • Fluid-Pressure Circuits (AREA)

Abstract

본 발명은 굴삭기의 붐제어장치에 관한 것으로, 특히 유압이 배관이 파손되는 경우와 같은 비상시에 붐이 하강하는 것을 방지하도록 하는 붐제어장치에 관한 것이다. 상기 본 발명의 굴삭기 붐제어장치는 유압펌프(1)의 압유를 방향제어하여 붐상승 유압라인(2)과 붐하강 유압라인(3)을 통하여 붐실린더(4)의 헤드측 체임버(4a)나 로드측 체임버(4b)에 선택적으로 공급하는 붐콘트롤밸브(5)와, 상기 붐콘트롤밸브(5)의 양쪽 각 수압부(5a,5b)에 붐상승 및 붐하강 파이롯신호를 제공하는 파이롯제어밸브(6)와, 상기 유압펌프(1)의 압유를 상기 붐실린더(4)의 헤드측 체임버(4a)로 유입시는 자유로이 유입되게 하지만, 배출은 상기 파이롯제어밸브(6)의 붐하강 파이롯신호압이 인가될 때에만 허용하는 로드홀딩밸브(10)를 포함한 굴삭기의 붐제어장치에 있어서, The present invention relates to a boom control device of an excavator, and more particularly to a boom control device to prevent the boom from lowering in an emergency, such as when the hydraulic pipe is broken. Excavator boom control device of the present invention is the head side chamber (4a) of the boom cylinder (4) through the boom up hydraulic line (2) and boom down hydraulic line (3) by controlling the pressure of the hydraulic pump (1) direction A pilot for providing a boom up and down boom pilot signal to the boom control valve 5 selectively supplied to the rod side chamber 4b and the hydraulic parts 5a and 5b of the boom control valve 5 respectively. While the control valve 6 and the hydraulic oil of the hydraulic pump 1 flow into the head side chamber 4a of the boom cylinder 4 freely, the discharge flows freely, but the discharge is caused by the boom of the pilot control valve 6. In the boom control apparatus of an excavator including a rod holding valve (10) to be allowed only when a falling pilot signal pressure is applied,

상기 파이롯제어밸브(6)와 로드홀딩밸브(10) 사이의 붐하강 파이롯신호라인(6b)상에 설치되며, 일측 수압부는 붐실린더(4)의 붐상승 및 하강 유압라인(2,3)으로부터 분기된 유압라인(2a,3a)과 연결되고, 타측 수압부는 스프링(22)에 의해 탄성지지되는 록킹밸브(20)를 포함하는 구성으로 된 것이다.It is installed on the boom lowering pilot signal line (6b) between the pilot control valve 6 and the rod holding valve 10, one side of the hydraulic pressure section of the boom cylinder (4) boom up and down hydraulic line (2, 3) It is connected to the hydraulic line (2a, 3a) branched from), the other hydraulic pressure unit is configured to include a locking valve 20 is elastically supported by the spring (22).

붐하강, 굴삭기, 로드홀딩Boom Lower, Excavator, Road Holding

Description

굴삭기의 붐제어장치{ boom control device in an excavator}Boom control device in an excavator

도 1은 종래 굴삭기의 붐제어장치에 대한 개략적인 유압회로도,1 is a schematic hydraulic circuit diagram of a boom control device of a conventional excavator;

도 2는 본 발명에 따른 붐제어장치의 개략적인 유압회로도이다.
2 is a schematic hydraulic circuit diagram of a boom control apparatus according to the present invention.

※ 도면의 주요부분에 대한 부호의 설명※※ Explanation of code about main part of drawing ※

1: 유압펌프 2: 붐상승 유압라인1: hydraulic pump 2: boom lift hydraulic line

3: 붐하강 유압라인 2a,3a: 유압라인3: Hydraulic boom down line 2a, 3a: Hydraulic line

4: 붐실린더 4a: 헤드측 체임버4: boom cylinder 4a: head side chamber

4b: 로드측 체임버 5: 붐제어스풀4b: Rod side chamber 5: Boom control spool

5a,5b: 수압부 6: 파이롯제어밸브5a, 5b: Hydraulic part 6: pilot control valve

6a: 붐상승 파이롯신호라인 6b: 붐하강 파이롯신호라인6a: Boom Rising Pilot Signal Line 6b: Boom Rising Pilot Signal Line

10: 로드홀딩밸브 10a: 수압부10: rod holding valve 10a: water pressure part

11: 체크밸브 12: 오리피스 11: check valve 12: orifice

13: 분기라인 13a: 체크밸브13: branch line 13a: check valve

20: 록킹밸브 22: 스프링

20: locking valve 22: spring

본 발명은 굴삭기와 같은 유압건설중장비에서 붐을 제어하는 장치에 관한 것으로, 특히 비상시에 붐의 하강을 억제하는 붐제어장치에 관한 것이다. The present invention relates to a device for controlling a boom in a hydraulic construction equipment such as an excavator, and more particularly to a boom control device for suppressing the lowering of the boom in an emergency.

일반적으로 굴삭기에서 운전하지 않을 때 붐의 자중에 의한 하강을 억제하여 의도하지 않은 붐하강에 따른 안전사고를 예방하고 장비의 손상을 방지하도록 하는 붐록킹장치가 제안되어 있다 In general, a boom locking device has been proposed to prevent the safety accident caused by unintentional boom lowering and to prevent equipment damage by suppressing the lowering of the boom when not operating in an excavator.

이러한 붐록킹장치는 도 1에 도시된 바와 같이, 유압펌프(1)의 압유를 방향제어하여 붐상승 유압라인(2)과 붐하강 유압라인(3)을 통하여 붐실린더(4)의 헤드측 체임버(4a)나 로드측 체임버(4b)에 선택적으로 공급하는 붐콘트롤밸브(5)와, 상기 붐콘트롤밸브(5)의 양쪽 각 수압부(5a,5b)에 붐상승 및 붐하강 파이롯신호를 제공하는 파이롯제어밸브(6)를 포함한 굴삭기의 붐제어장치에서 상기 유압펌프(1)의 압유가 상기 붐실린더(4)의 헤드측 체임버(4a)로 유입될 때에는 자유로이 유입되게 하지만, 배출은 파이롯제어밸브(6)의 붐하강 파이롯신호압이 인가될 때에만 허용하는 로드홀딩밸브(10)로 구성되어 있다. As shown in FIG. 1, the boom locking device controls the oil pressure of the hydraulic pump 1 to direct the head side chamber of the boom cylinder 4 through the boom raising hydraulic line 2 and the boom lowering hydraulic line 3. Boom up and down boom pilot signals are supplied to the boom control valve 5 selectively supplied to 4a and the rod side chamber 4b, and the hydraulic parts 5a and 5b of the boom control valve 5, respectively. When the hydraulic oil of the hydraulic pump 1 flows into the head side chamber 4a of the boom cylinder 4 from the boom control device of the excavator including the pilot control valve 6 provided, the discharge is freely introduced. It consists of a rod holding valve 10 which allows only when the boom lowering pilot signal pressure of the pilot control valve 6 is applied.

그러나 상기와 같은 종래 붐록킹장치는 작업자가 붐을 하강시키고 있는 도에중(이 때 붐하강 파이롯신호압력이 붐제어스풀에 작용하고 있다) 붐실린더에서 유압을 배출하는 유압배관(도 1의 도면부호 2)이 파손되는 경우에는 상기 로드홀딩밸브(10)는 상기 붐하강 파이롯신호압에 의해 여전히 유로를 개방하고 있으므로 붐은 자중에 의해 하강하게 되어 안전사고의 위험이 따른다. However, the conventional boom locking device as described above has a hydraulic pipe for discharging hydraulic pressure from the boom cylinder while the worker is lowering the boom (in this case, the boom lowering pilot signal pressure acts on the boom control spool). When the reference numeral 2) is broken, the rod holding valve 10 still opens the flow path due to the boom lowering pilot signal pressure, so that the boom is lowered by its own weight, resulting in a safety accident.

이에 본 발명은 상기 종래 굴삭기에서 붐제어장치가 가진 문제점을 해결하기 위하여 고안된 것으로, 붐 유압배관이 파손되었을 경우에 작업자가 의도하지 않는 붐의 하강을 억제하는 붐제어장치를 제공함에 목적이 있다. The present invention is designed to solve the problems of the boom control device in the conventional excavator, it is an object of the present invention to provide a boom control device for suppressing the unintentional lowering of the boom when the boom hydraulic pipe is broken.

상기 목적을 달성하기 위한 본 발명은 유압펌프의 압유를 방향제어하여 붐상승 유압라인과 붐하강 유압라인을 통하여 붐실린더의 헤드측 체임버나 로드측 체임버에 선택적으로 공급하는 붐콘트롤밸브와, 상기 붐콘트롤밸브의 양쪽 각 수압부에 붐상승 및 붐하강 파이롯신호를 제공하는 파이롯제어밸브와, 상기 유압펌프의 압유를 상기 붐실린더의 헤드측 체임버로 유입시는 자유로이 유입되게 하지만, 배출은 상기 파이롯제어밸브의 붐하강 파이롯신호압이 인가될 때에만 허용하는 로드홀딩밸브를 포함한 굴삭기의 붐제어장치에 있어서, The present invention for achieving the above object is a boom control valve for selectively supplying to the head-side chamber or rod-side chamber of the boom cylinder through the boom up hydraulic line and the boom down hydraulic line by directional control of the hydraulic pressure of the hydraulic pump, and the boom A pilot control valve for providing a boom up and down boom pilot signal to each of the hydraulic parts of the control valve and the hydraulic oil of the hydraulic pump are freely introduced when flowing into the head side chamber of the boom cylinder. In the boom control apparatus of an excavator including a rod holding valve which allows only when the boom lowering pilot signal pressure of the pilot control valve is applied,

상기 파이롯제어밸브와 로드홀딩밸브 사이의 붐하강 파이롯신호라인상에 설치되며, 일측 수압부는 붐실린더의 붐상승 및 하강 유압라인으로부터 분기된 유압라인과 연결되고, 타측 수압부는 스프링에 의해 탄성지지되는 록킹밸브를 포함한 구성으로 된다.It is installed on the boom lowering pilot signal line between the pilot control valve and the rod holding valve, one hydraulic part is connected to the hydraulic line branched from the boom up and down hydraulic line of the boom cylinder, the other hydraulic part is elastic by spring The locking valve is supported.

상기한 구성으로 된 본 발명의 붐제어장치에 의하면, 붐실린더의 유압라인이 파손되는 경우에 상기 록킹밸브는 붐하강 파이롯신호가 붐제어스풀에 작용하지 않도록 차단함으로써 작업자가 의도하지 않은 붐하강을 방지하여 안전사고나 장비손 상을 예방할 수 있게 된다.
According to the boom control apparatus of the present invention having the above-described configuration, when the hydraulic line of the boom cylinder is damaged, the locking valve blocks the boom lowering pilot signal from acting on the boom control spool, thereby unintentionally lowering the boom. This prevents safety accidents and equipment damage.

이하, 본 발명에 따른 굴삭기의 붐제어장치의 실시예를 첨부도면에 따라 상세히 설명한다. Hereinafter, an embodiment of the boom control device of an excavator according to the present invention will be described in detail according to the accompanying drawings.

본 발명에 따른 굴삭기의 붐제어장치는, 도 2에 도시된 바와 같이, 유압펌프(1)의 압유를 방향제어하여 붐상승 유압라인(2)과 붐하강 유압라인(3)을 통하여 붐실린더(4)의 헤드측 체임버(4a)나 로드측 체임버(4b)에 선택적으로 공급하는 붐콘트롤밸브(5)와, 상기 붐콘트롤밸브(5)의 양쪽 각 수압부(5a,5b)에 붐상승 및 붐하강 파이롯신호를 제공하는 파이롯제어밸브(6)와, 상기 유압펌프(1)의 압유를 상기 붐실린더(4)의 헤드측 체임버(4a)로 유입시는 자유로이 유입되게 하지만, 배출은 상기 파이롯제어밸브(6)의 붐하강 파이롯신호압이 인가될 때에만 허용하는 로드홀딩밸브(10)를 포함한다. The boom control device of the excavator according to the present invention, as shown in Figure 2, the boom cylinder through the boom rising hydraulic line (2) and the boom lowering hydraulic line (3) by directional control the hydraulic oil of the hydraulic pump ( Boom rises to the boom control valve 5 selectively supplied to the head side chamber 4a and the rod side chamber 4b of 4), and the hydraulic parts 5a and 5b of the boom control valve 5, respectively. The pilot control valve 6 providing the boom lowering pilot signal and the hydraulic oil of the hydraulic pump 1 are freely introduced into the head side chamber 4a of the boom cylinder 4, but the discharge is free. And a rod holding valve 10 which allows only when the boom lowering pilot signal pressure of the pilot control valve 6 is applied.

상기 로드홀딩밸브(10)는 상기 유압펌프(1)에서 붐실린더(4)의 헤드측 체임버(4a)로는 압유를 통과시키지만, 붐실린더(4)의 헤드측 체임버(4a)에서 탱크로 배출되는 압유의 흐름은 저지하는 체크밸브(11)와, 상기 붐실린더(4)의 헤드측 체임버(4a)에서 탱크로 배출되는 압유를 지연시키는 오리피스(12)을 포함하고, 일측에 수압부(10a)를 구비하고, 이 수압부(10a)에는 붐하강 파이롯라인(6b)에서 분기된 분기라인(13)이 체크밸브(13a)를 게재하여 연결되어 있다. The rod holding valve 10 passes the hydraulic oil from the hydraulic pump 1 to the head side chamber 4a of the boom cylinder 4, but is discharged from the head side chamber 4a of the boom cylinder 4 to the tank. The flow of the pressurized oil includes a check valve 11 for blocking and an orifice 12 for delaying the pressurized oil discharged from the head side chamber 4a of the boom cylinder 4 to the tank, on one side of the hydraulic part 10a. And a branching line 13 branched from the boom lowering pilot line 6b is connected to the hydraulic pressure section 10a by placing a check valve 13a.

그리고 상기 파이롯제어밸브(6)와 로드홀딩밸브(10) 사이의 붐하강 파이롯신호라인(6b)상에는 록킹밸브(20)가 설치된다. 이 록킹밸브(20)는 일측 수압부가 붐 실린더(4)의 붐상승 및 하강 유압라인(2,3)으로부터 분기된 유압라인(2a,3a)과 연결되고, 타측 수압부는 스프링(22)에 의해 탄성지지되어 있다.
A locking valve 20 is installed on the boom lowering pilot signal line 6b between the pilot control valve 6 and the rod holding valve 10. This locking valve 20 is connected to the hydraulic line (2a, 3a) branched from the hydraulic pressure line (2, 3) of the boom up and down the boom cylinder of one side of the boom cylinder (4), the other hydraulic pressure portion by the spring 22 It is elastically supported.

따라서 상기 록킹밸브(22)는 붐상승 유압라인(2)이나 붐하강 유압라인(3)중 적어도 어느 하나의 유압라인에 압유가 작용할 경우에만 상기 붐하강 파이롯신호압력이 붐제어스풀에 작용하게 하고, 상기 붐상승 유압라인이나 붐하강 유압라인이나 붐상승 유압라인에 모두 압유가 작용하지 않는 장비정지시 혹은 붐상승 또는 하강 유압라인이 파손되어 압력이 형성되지 않는 비상의 경우에는 붐하강 파이롯신호압력이 붐제어스풀에 작용하지 않게 차단함으로써 작업자가 의도하지 않은 붐하강을 방지할 수 있게 되는 것이다.
Accordingly, the locking valve 22 is such that the boom lowering pilot signal pressure acts on the boom control spool only when the hydraulic pressure acts on at least one hydraulic line of the boom up hydraulic line 2 or the boom down hydraulic line 3. The boom up and down boom, the boom up and down hydraulic line or the boom up and hydraulic line, both the equipment stops when the hydraulic pressure does not work or the boom up or down hydraulic line is damaged in case of emergency that the pressure is not formed, the boom down pilot By blocking the signal pressure from acting on the boom spool, the operator can prevent unintentional lowering of the boom.

이상과 같이, 본 발명의 붐제어장치에 의하면, 붐실린더의 유압라인이 파손되는 경우에 상기 록킹밸브는 붐하강 파이롯신호가 붐제어스풀에 작용하지 않도록 차단함으로써 작업자가 의도하지 않은 붐하강을 방지하여 안전사고나 장비손상을 예방할 수 있게 된다. As described above, according to the boom control device of the present invention, when the hydraulic line of the boom cylinder is broken, the locking valve blocks the boom lowering pilot signal from acting on the boom control spool to prevent the boom lowering unintentionally by the operator. This prevents safety accidents and equipment damage.

Claims (1)

유압펌프(1)의 압유를 방향제어하여 붐상승 유압라인(2)과 붐하강 유압라인(3)을 통하여 붐실린더(4)의 헤드측 체임버(4a)나 로드측 체임버(4b)에 선택적으로 공급하는 붐콘트롤밸브(5)와, 상기 붐콘트롤밸브(5)의 양쪽 각 수압부(5a,5b)에 붐상승 및 붐하강 파이롯신호를 제공하는 파이롯제어밸브(6)와, 상기 유압펌프(1)의 압유를 상기 붐실린더(4)의 헤드측 체임버(4a)로 유입시는 자유로이 유입되게 하지만, 배출은 상기 파이롯제어밸브(6)의 붐하강 파이롯신호압이 인가될 때에만 허용하는 로드홀딩밸브(10)를 포함한 굴삭기의 붐제어장치에 있어서, The hydraulic pressure of the hydraulic pump 1 is directionally controlled to selectively the head side chamber 4a or the rod side chamber 4b of the boom cylinder 4 through the boom raising hydraulic line 2 and the boom lowering hydraulic line 3. A boom control valve (5) for supplying, a pilot control valve (6) for providing a boom up and down boom pilot signals to each of the hydraulic parts (5a, 5b) of the boom control valve (5); When the pressure oil of the pump 1 flows into the head side chamber 4a of the boom cylinder 4 freely, the discharge flows freely, but when the boom descending pilot signal pressure of the pilot control valve 6 is applied. In the boom control device of an excavator including a rod holding valve 10 that allows only 상기 파이롯제어밸브(6)와 로드홀딩밸브(10) 사이의 붐하강 파이롯신호라인(6b)상에 설치되며, 일측 수압부는 붐실린더(4)의 붐상승 및 하강 유압라인(2,3)으로부터 분기된 유압라인(2a,3a)과 연결되고, 타측 수압부는 스프링(22)에 의해 탄성지지되는 록킹밸브(20)를 포함하는 것을 특징으로 하는 굴삭기의 붐제어장치.It is installed on the boom lowering pilot signal line (6b) between the pilot control valve 6 and the rod holding valve 10, one side of the hydraulic pressure section of the boom cylinder (4) boom up and down hydraulic line (2, 3) Is connected to the hydraulic line (2a, 3a) branched from), the other hydraulic pressure portion of the excavator boom control device comprising a locking valve 20 is elastically supported by the spring (22).
KR1020010088811A 2001-12-31 2001-12-31 boom control device in an excavator KR100813779B1 (en)

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KR100976924B1 (en) * 2003-11-11 2010-08-18 두산인프라코어 주식회사 Arm locking apparatus with air ventilation in an excavator
KR101265342B1 (en) * 2006-12-22 2013-05-20 두산인프라코어 주식회사 Flat and slant improvement device of excavator

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06294149A (en) * 1993-04-07 1994-10-21 Hitachi Constr Mach Co Ltd Hydraulic drive device for hydraulic shovel
JPH07279905A (en) * 1994-04-04 1995-10-27 Komatsu Ltd Controller for operating cylinder
JP2000230254A (en) * 1999-02-10 2000-08-22 Shin Caterpillar Mitsubishi Ltd Control method and control device for hydraulic fluid
KR20030003792A (en) * 2001-07-02 2003-01-14 가부시키가이샤 고마쓰 세이사쿠쇼 Hydraulic exacavator

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06294149A (en) * 1993-04-07 1994-10-21 Hitachi Constr Mach Co Ltd Hydraulic drive device for hydraulic shovel
JPH07279905A (en) * 1994-04-04 1995-10-27 Komatsu Ltd Controller for operating cylinder
JP2000230254A (en) * 1999-02-10 2000-08-22 Shin Caterpillar Mitsubishi Ltd Control method and control device for hydraulic fluid
KR20030003792A (en) * 2001-07-02 2003-01-14 가부시키가이샤 고마쓰 세이사쿠쇼 Hydraulic exacavator

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