KR920008658Y1 - Oil-pressure control device of excavator - Google Patents
Oil-pressure control device of excavator Download PDFInfo
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- KR920008658Y1 KR920008658Y1 KR2019880021921U KR880021921U KR920008658Y1 KR 920008658 Y1 KR920008658 Y1 KR 920008658Y1 KR 2019880021921 U KR2019880021921 U KR 2019880021921U KR 880021921 U KR880021921 U KR 880021921U KR 920008658 Y1 KR920008658 Y1 KR 920008658Y1
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- 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
- E02F3/425—Drive systems for dipper-arms, backhoes or the like
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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
- E02F9/2221—Control of flow rate; Load sensing arrangements
- E02F9/2225—Control of flow rate; Load sensing arrangements using pressure-compensating valves
- E02F9/2228—Control of flow rate; Load sensing arrangements using pressure-compensating valves including an electronic controller
-
- 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
- E02F9/2239—Control of flow rate; Load sensing arrangements using two or more pumps with cross-assistance
- E02F9/2242—Control of flow rate; Load sensing arrangements using two or more pumps with cross-assistance including an electronic controller
-
- 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
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- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Civil Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- Operation Control Of Excavators (AREA)
Abstract
내용 없음.No content.
Description
제1도는 본 고안에 따른 장치의 유압회로도.1 is a hydraulic circuit diagram of the device according to the present invention.
제2도는 종래 굴삭기의 개략적 유압회로도이다.2 is a schematic hydraulic circuit diagram of a conventional excavator.
* 도면의 주요부분에 대한 부호의 설명* Explanation of symbols for the main parts of the drawings
1 : 엔진 2,3 : 제1,2유압펌프1: engine 2,3: 1st, 2nd hydraulic pump
4 : 보조유압펌프 5,6,7,8,9,10 : 작동기4: auxiliary hydraulic pump 5,6,7,8,9,10: actuator
5a,6a,7a,8a,9a,10a : 제어밸브 11,12,13 : 솔레노이드밸브부 로직밸브5a, 6a, 7a, 8a, 9a, 10a: control valve 11, 12, 13: solenoid valve section logic valve
11a,12a,13a : 솔레노이드밸브 14,15 : 릴리이프밸브11a, 12a, 13a: solenoid valve 14, 15: relief valve
14a,15a : 솔레노이드 16 : 전자식 유량배분블럭14a, 15a: solenoid 16: electronic flow distribution block
17,18 : 조정기구 19,20 : 감압밸브17,18: adjusting mechanism 19,20: pressure reducing valve
19a,20a : 솔레노이드 21 : 주행페달19a, 20a: solenoid 21: running pedal
22 : 조종간 23 : 제어부22: joystick 23: control unit
24 : 탱크24 tank
본 고안은 굴삭기의 유압제어장치에 관한 것으로, 특히 굴삭기에 설치된 여러개의 작업기 즉 부움, 버킷 및, 아암 등에 유압펌프로부터 토출되는 유량을 적절하게 분배공급하고, 또 작동기의 작동상태에 따라 펌프토출량을 최적상태로 제어해 주도록 한 굴삭기의 유압제어장치에 관한 것이다.The present invention relates to a hydraulic control device of an excavator, in particular, to distribute the flow rate discharged from the hydraulic pump to a plurality of work machines installed in the excavator, such as pour, bucket and arm, appropriately, the pump discharge amount according to the operating state of the actuator The present invention relates to a hydraulic control device of an excavator that is optimally controlled.
통상적으로 굴삭기의 유압장치는 1대의 엔진에 의해 구동되는 2개이상의 유압펌프에 의해 부움실린더와 아암실린더, 버킷실린더, 선회모우터 및, 좌우주행모우터등과 같은 여러개의 작동기를 작동시키도록 되어 있는바, 이러한 각 작동기의 기동, 정지 및 속도조절은 유압펌프에 연결된 제어밸브를 조작해 줌으로써 이루어지게 되며, 각 작동기와 제어밸브는 실제작업에 지장을 받지 않도록 조합되어 있다.Typically, the hydraulic system of an excavator is operated by two or more hydraulic pumps driven by one engine to operate several actuators such as a boom cylinder, an arm cylinder, a bucket cylinder, a turning motor, and a left and right driving motor. As such, the start, stop, and speed control of each of these actuators is achieved by operating a control valve connected to the hydraulic pump, and each actuator and control valve are combined so as not to interfere with actual operation.
그러나 일반적인 종래의 굴삭기유압장치는 제2도에 도시된 바와 같이 2개의 유압펌프를 사용한 병렬유압회로로 이루어져 있기 때문에 한쪽방향에 있는 작동기(101,102,103,104)를 사용할 때 유압펌프(a)만 이용되고, 다른쪽 방향에 있는 작동기(105,106,107,108)들을 사용할 때에는 유압펌프(b)만을 이용하여 작동유를 공급시켜 주도록 하면서 필요에 따라 부분적으로 2개의 유압펌프(a,b)로부터 공급되는 작동유를 합류시켜 사용하도록 되어 있다. 따라서 한쪽에 있는 작동기의 각각을 개별적으로 작동시켜 주고자 할 때, 이 작동기에 연결되어 있는 밸브들 역시 상기 유압펌프(a)와 병렬연결되어 있기 때문에 작동시 서로의 간섭에 의해 정확한 작동제어가 이루어지지 않을 뿐만 아니라, 더욱이 다른쪽 유압펌프(b)의 여유유량을 합류시키더라도 예컨대 2개의 작동기(101,102)만을 작동시키고자 할 때 이들 각각의 작동기에 정확한 유량을 분배해줄 수가 없었다.However, since a conventional conventional excavator hydraulic device is composed of a parallel hydraulic circuit using two hydraulic pumps as shown in FIG. 2, only the hydraulic pump (a) is used when using the actuators 101, 102, 103 and 104 in one direction. When using the actuators 105, 106, 107 and 108 in the lateral direction, the hydraulic oil is supplied using only the hydraulic pump b, and the hydraulic oil supplied from the two hydraulic pumps a and b is combined as necessary. . Therefore, in order to operate each of the actuators on one side individually, since the valves connected to the actuators are also connected in parallel with the hydraulic pump (a), accurate operation control is achieved by mutual interference during operation. Not only that, but joining the surplus flow rates of the other hydraulic pump (b) could not distribute the correct flow rate to each of these actuators, for example when only two actuators 101 and 102 were to be operated.
이에 본 고안은 상기 문제점을 해결하기 위해 안출된 것으로서, 2개의 유압펌프로부터 토출되는 유량을 각 작동기에 적절히 배분공급해 줄 수가 있고, 또 작동기의 작동상태에 따라 펌프의 토출량을 최적상태로 제어해 줄 수 있도록 한 굴삭기의 유압제어장치를 제공하는데 그 목적이 있다.Therefore, the present invention has been devised to solve the above problems, and it is possible to appropriately distribute the flow rate discharged from the two hydraulic pumps to each actuator, and to control the discharge amount of the pump to the optimal state according to the operating state of the actuator. It is an object of the present invention to provide an excavator hydraulic control device.
상기한 바의 목적을 달성하기 위한 본 고안에 따른 장치는, 전기식 주행페달과 전기식 작동기의 조정간의 조작상태에 따라 발생되는 조작신호를 입력받아 이를 연산처리해 주는 전자식 제어부에 유압펌프에 토출량을 조절해 주는 감압밸브가 연결되고, 유압펌프로부터 토출되는 작동유를 공급받아 작동하는 각각의 작동기에 작동유의 공급을 제어해 주는 각각의 제어밸브에 상기 2대의 유압펌프사이에 솔레노이드밸브부 양방향로직밸브부와 릴리이프밸브로 이루어지는 전자식 유량배분블럭이 설치되어 상기 각각의 작동기를 병렬연결시켜며, 상기 전자식 유량배분블럭내의 양방향로직밸브 및 릴리이프밸브에 부착된 솔레노이드밸브는 상기 전자식 제어부와 연결되어, 전기식 작동기조종간과 주행페달의 조작상태에 따라 유압펌프로부터 토출되는 작동유의 공급량이 조절되면서 이 작동유를 적절히 분배공급해 주도록 되어 있다.The apparatus according to the present invention for achieving the object of the above, by adjusting the discharge amount to the hydraulic pump to the electronic control unit that receives the operation signal generated according to the operation state between the adjustment of the electric running pedal and the electric actuator to process it The main valve is connected to the pressure reducing valve, and the solenoid valve section bidirectional logic valve section and the relief are provided between the two hydraulic pumps at respective control valves for controlling the supply of the hydraulic oil to each actuator operating by receiving the hydraulic oil discharged from the hydraulic pump. An electronic flow distribution block consisting of an if valve is installed to connect the respective actuators in parallel, and a solenoid valve attached to the bidirectional logic valve and the relief valve in the electronic flow distribution block is connected to the electronic control unit. And discharged from the hydraulic pump according to the operating state of the running pedal While adjusting the supply of tung oil is supplied to give proper distribution of the fluid.
이하 본 고안을 첨부된 예시도면에 의거 상세히 설명한다.Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.
본 고안은 제1도에 도시된 바와 같이 굴삭기의 엔진(1)에 의해 제1,2유압펌프(2,3)와 보조유압펌프(4)가 구동되도록 병렬연결되어 있고, 상기 제1,2유압펌프(2,3)와 이들 유압펌프(2,3)로부터 가압토출되는 작동유를 공급받아 작동되는 각각의 작동기(5,6,7,8,9,10)에 작동유의 공급을 제어해 주는 각각의 제어밸브(5a,6a,7a,8a,9a,10a)의 사이에 3개의 솔레노이드부 양방향 로직밸브(11,12,13) 및 2개의 솔레노이드밸브부 릴리이프밸브(14,15)로 이루어지는 전자식 유량배분블럭(16)이 설치되어, 상기 각각의 작동기(5,6,7,8,9,10)를 병렬연결시켜 주도록 되어 있으며, 상기 보조유압펌프(4)는 상기 제1,2유압펌프(2,3)의 사판각조정기구(17,18)를 전자비례적으로 조절해 주는 전자비례감압밸브(19,20)와 연결되어, 이 보조유압펌브(4)에서 토출되는 작동유에 의해 상기 제1,2유압펌프(2,3)의 사판각조정기구(17,18)를 작동시켜줌으로써 이들 유압펌프(2,3)에서 토출되는 공급유량을 조절해 주도록 되어 있다.The present invention is connected in parallel so that the first and second hydraulic pumps 2 and 3 and the auxiliary hydraulic pump 4 are driven by the engine 1 of the excavator, as shown in FIG. Control the supply of hydraulic oil to the hydraulic pump (2,3) and each of the actuators (5,6,7,8,9,10) operated by receiving hydraulic oil pressurized from these hydraulic pumps (2,3) It consists of three solenoid part bidirectional logic valves 11, 12, 13 and two solenoid valve part relief valves 14, 15 between each control valve 5a, 6a, 7a, 8a, 9a, 10a. An electronic flow rate distribution block 16 is installed to connect the respective actuators 5, 6, 7, 8, 9 and 10 in parallel, and the auxiliary hydraulic pump 4 is connected to the first and second hydraulic pressures. It is connected to the electromagnetic proportional pressure reducing valves 19 and 20 for controlling the swash plate angle adjusting mechanisms 17 and 18 of the pumps 2 and 3 electronically in proportion, and by the hydraulic oil discharged from the auxiliary hydraulic pump 4. The first and second hydraulic pumps 2 and 3 By operating the swash plate angle adjusting mechanisms 17 and 18, the supply flow rates discharged from these hydraulic pumps 2 and 3 are adjusted.
한편, 본 고안에 따른 굴삭기에서 채용하고 있는 주행페달(21)과 조정간(22)은 전기식으로 조절되도록 되어 있는 것으로서, 이들 전기식 주행페달(21)과 전기식 조종간(22)의 조절상태에 따라 발생되는 전기적신호는 상기 주행페달(21)과 조종간(22)에 전기적으로 연결되어 있는 제어부(23)에 인가되어 연산처리되게 되고, 이 제어부(23)에서 연산처리되어 출력되는 출력신호는 상기 유량배분블럭(16)의 양방향로직밸브(11,12,13)와 릴리이프밸브(14,15)에 부착되어 있으면서 상기 전자적 제어부(23)와 연결되어 있는 각각의 솔레노이드밸브(11a,12a,13a) 및 솔레노이드(14a,15a)를 작동시켜 주도록 되어 있는 한편, 상기 제어부(23)는 제1,2유압펌프(2,3)의 사각판조정기구(17,18)와 연결된 전자비례감압밸브(19,20)의 솔레노이드(19a,20a)에도 전기적으로 연결되어 상기 연산처리된 출력신호를 상기 솔레노이드(19a,20a)에 전달해 줌으로써 전자비례감압밸브(19,20)를 통해 사판각조정기구(17,18)로 공급되는 작동유의 공급량을 조절해 주도록 되어 있다.On the other hand, the driving pedal 21 and the adjustment period 22 employed in the excavator according to the present invention is to be adjusted electrically, which is generated in accordance with the adjustment state of the electric driving pedal 21 and the electric steering wheel 22. The electrical signal is applied to the control unit 23 which is electrically connected to the driving pedal 21 and the steering wheel 22 to be arithmetic processed, and the output signal calculated and processed by the control unit 23 is the flow rate distribution block. Solenoid valves 11a, 12a, 13a and solenoids attached to the bidirectional logic valves 11, 12, 13 and relief valves 14, 15 of 16, and connected to the electronic control unit 23, respectively. 14a and 15a, while the control unit 23 is provided with electromagnetic proportional pressure reducing valves 19 and 20 connected to the square plate adjusting mechanisms 17 and 18 of the first and second hydraulic pumps 2 and 3, respectively. Is electrically connected to the solenoids 19a and 20a of By transmitting the output signal to the solenoids 19a and 20a, the amount of hydraulic oil supplied to the swash plate angle adjusting mechanisms 17 and 18 through the electromagnetic proportional pressure reducing valves 19 and 20 is adjusted.
이와 같이 이루어진 본 고안에 따른 장치는, 제1도에 도시된 바와 같이 엔진(1)으로부터 구동되는 가변용량형 제1,2유압펌프(2,3)의 토출유량을 이용하여 구동하는 굴삭기의 유압장치로서, 각 작동기(5,6,7,8,9,10)인 부움실린더, 버킷실린더, 아암실린더, 주행모우터 및, 선회모우터를 작업필요에 따라 조작하는 주행페달(21)과 조종간(22)의 신호가 제어부로 입력되어, 이 제어부(23)에 각각 병렬연결된 전자식 유량배분블럭(16)의 각각의 밸브들과 전자비례감압밸브(19,20)의 솔레노이드(19a,20a)에 출력신호를 보내어 작동하고자 하는 작동기(5,6,7,8,9,10)에 유량을 공급시키도록 되어 있다.The apparatus according to the present invention made in this way, as shown in Figure 1, the hydraulic pressure of the excavator driven by using the discharge flow rate of the variable displacement first and second hydraulic pumps (2,3) driven from the engine (1) As a device, each actuator 5, 6, 7, 8, 9, 10, a boom cylinder, a bucket cylinder, an arm cylinder, a traveling motor, and a traveling pedal 21 for operating a turning motor according to a work need and a steering wheel The signal of (22) is input to the control unit, and to the solenoids (19a, 20a) of the respective valves and the electromagnetic proportional pressure reducing valves (19, 20) of the electromagnetic flow distribution block (16) connected in parallel to the control unit (23), respectively. The flow rate is supplied to the actuators 5, 6, 7, 8, 9 and 10 to be operated by sending an output signal.
또한 상기 제1,2유압펌프(2,3)에 연결된 보조유압펌프(4)에는 상기 제1,2유압펌프(2,3)의 유량을 조절하는 사각판조정기구(17,18)에 연결된 전자비례감압밸브(19,20)가 병렬조절되어 상기 제1,2유압펌프(2,3)의 토출량을 적절히 조정하도록 되어 있는바, 예를들어 버킷과 부움실린더이 작동기(6,5)를 작동시키고자 할 때 조정간(22)을 조작하여 상기 제어부(23)로부터 전자식 유량배분블럭(16)의 각 양방향 로직밸브(11,12,13)들에 신호를 출력하여 상기 로직밸브(11,12,13)들의 솔레노이드밸브(11a,12a,13a)를 작동시켜 이 로직밸브(11,12)들을 개방시키는 한편, 다른 양방향로 직밸브(13)를 차단시키게 되면, 제1유압펌프(2)에서 토출된 압유는 상기 개방된 로직밸브(12,11)를 거쳐 버킷실린더인 작동기(6)에 연결된 제어밸브(6a)를 통하여 이 작동기(6)를 작동시킴과 동시에 제2유압펌프(3)에서 토출된 압유는 이 제2유압펌프(3)와 직렬연결된 로직밸브(13)가 페쇄되어져 있기 때문에 부움실린더의 작동기(6,5)가 정확하게 작동되면서 서로의 조작독립성이 향상된다.In addition, the auxiliary hydraulic pump 4 connected to the first and second hydraulic pumps 2 and 3 is connected to the square plate adjustment mechanisms 17 and 18 for adjusting the flow rates of the first and second hydraulic pumps 2 and 3. The electromagnetic proportional pressure reducing valves 19 and 20 are adjusted in parallel so as to properly adjust the discharge amount of the first and second hydraulic pumps 2 and 3, for example, the bucket and the pour cylinder operate the actuators 6 and 5. When the control unit 22 is operated, a signal is output from the control unit 23 to the bidirectional logic valves 11, 12, and 13 of the electronic flow distribution block 16 to control the logic valves 11, 12, When the solenoid valves 11a, 12a, 13a of 13 are operated to open these logic valves 11, 12, and the direct valve 13 is blocked in the other direction, the first hydraulic pump 2 discharges. The pressurized oil is operated through the control valve 6a connected to the actuator 6 which is a bucket cylinder via the open logic valves 12 and 11, and at the same time the second hydraulic pressure Since the logic valve 13 connected in series with the second hydraulic pump 3 is closed, the hydraulic oil discharged from the pump 3 is correctly operated and the operation independence of each other is improved. .
한편 1개의 작동기(6)를 작동시키고자 할 때, 상기 제어부(23)의 출력신호는 상기 전자식 유량배분블럭(16)의 양방향 로직밸브(11,12,13)들 모두를 개방시키게 되면, 제1,2유압펌프(2,3) 토출된 압유 모두로 1개의 작동기(6)로 공급되고, 제2유압펌프(3)에서 토출된 유량은 이에 연결된 로직밸브(13)를 거쳐 상기 제1유압펌프(2)에서 토출된 유량과 함께 합류하여 상기 제어밸브(6a)를 통하여 작동기(6)에 공급되어 간다.On the other hand, when one actuator 6 is to be operated, the output signal of the controller 23 opens all of the bidirectional logic valves 11, 12, 13 of the electronic flow distribution block 16. 1,2 hydraulic pumps (2,3) are supplied to one actuator (6) with all of the discharged pressure oil, and the flow rate discharged from the second hydraulic pump (3) passes through the logic valve (13) connected to the first hydraulic pressure. It joins with the flow volume discharged from the pump 2, and is supplied to the actuator 6 via the control valve 6a.
따라서 본 고안에 따른 장치에서는 종래의 장치인 제2도에서와 같이 양쪽 펌프(a,b)의 토출량 일부를 바이패스시켜 탱크로 귀환시킬 필요가 없어, 단지 제1,2유압펌프(2,3)의 토출유량을 반으로 줄여 공급시키기 때문에 유압펌프에 보다 적은 부하가 걸려 내구성이 향상될 뿐만 아니라 불필요한 유량손실을 막을 수가 있다.Therefore, in the apparatus according to the present invention, as shown in FIG. 2, which is a conventional apparatus, it is not necessary to bypass a part of the discharge amount of both pumps a and b to return to the tank. Since the discharge flow rate is reduced to half, the hydraulic pump is loaded with less load, which improves durability and prevents unnecessary flow loss.
또한 상기 작동기(5,6,7,8,9,10) 등을 사용하지 않을 때 예컨대 덤프작업시 차량을 기다리는 작업도중에는 상기 주행페달(21)과 조종간(22)의 신호조작에 의해 제어부(23)는 전자식 유량배분블럭(16)의 양쪽 릴리이프밸브(14,15)에 전기적인 신호를 보내 릴리이프압력을 최소로하여 제1,2유압펌프(2,3)에서 토출된 유량이 이들 릴리이프밸브(14,15)를 거쳐 탱크(24)로 귀환되도록 작용시키므로써 유압손실을 최소로 방지할 수 있도록 되어 있다.In addition, when the actuators 5, 6, 7, 8, 9, 10, etc. are not used, for example, during the operation of waiting for the vehicle during the dumping operation, the control unit 23 is controlled by the signal manipulation of the driving pedal 21 and the steering wheel 22. ) Sends electrical signals to both relief valves 14 and 15 of the electronic flow distribution block 16 to minimize the relief pressure so that the flow rate discharged from the first and second hydraulic pumps 2 and 3 By acting to return to the tank 24 via the if valve (14, 15), it is possible to minimize the hydraulic loss.
이상과 같이 본 고안에 따른 굴삭기의 유압제어장치는 솔레노이드밸브부 양방향 로직밸브들과 릴이이프밸브들로 이루어진 전자식 유량배분블럭이 2개의 유압펌프사이에 연결되어 상기 각각의 작동기들과 병렬로 연결되어 이루어지므로써, 유압펌프들로부터 토출되는 압유를 각 작동기에 적절히 배분공급해 줄 수가 있고, 또 작동기의 작동상태에 따라 유압펌프의 토출량을 최적상태로 제어해줄 수 있는 효과가 있다.As described above, the hydraulic control device of the excavator according to the present invention has an electronic flow rate distribution block consisting of solenoid valve portion bidirectional logic valves and relief valves connected between two hydraulic pumps in parallel with the respective actuators. Since the pressure oil discharged from the hydraulic pumps can be properly distributed and supplied to each actuator, the discharge amount of the hydraulic pump can be optimally controlled according to the operating state of the actuator.
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KR2019880021921U KR920008658Y1 (en) | 1988-12-29 | 1988-12-29 | Oil-pressure control device of excavator |
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KR2019880021921U KR920008658Y1 (en) | 1988-12-29 | 1988-12-29 | Oil-pressure control device of excavator |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
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KR100621985B1 (en) * | 2005-08-02 | 2006-09-11 | 볼보 컨스트럭션 이키프먼트 홀딩 스웨덴 에이비 | System for driving |
WO2014123368A1 (en) * | 2013-02-08 | 2014-08-14 | 두산인프라코어 주식회사 | Apparatus and method for controlling oil hydraulic pump for excavator |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
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KR100621976B1 (en) * | 2002-04-24 | 2006-09-13 | 볼보 컨스트럭션 이키프먼트 홀딩 스웨덴 에이비 | construction heavy equipment of having boom down function |
KR100610881B1 (en) * | 2004-04-29 | 2006-08-11 | 주식회사수산중공업 | An Oil Control Device of Construction Machine |
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1988
- 1988-12-29 KR KR2019880021921U patent/KR920008658Y1/en not_active IP Right Cessation
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
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KR100621985B1 (en) * | 2005-08-02 | 2006-09-11 | 볼보 컨스트럭션 이키프먼트 홀딩 스웨덴 에이비 | System for driving |
WO2014123368A1 (en) * | 2013-02-08 | 2014-08-14 | 두산인프라코어 주식회사 | Apparatus and method for controlling oil hydraulic pump for excavator |
KR20140101701A (en) * | 2013-02-08 | 2014-08-20 | 두산인프라코어 주식회사 | Hydraulic pump controlling apparatus and method for an excavator |
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