KR100640538B1 - Flow control apparatus of hydraulic pump for excavators - Google Patents

Flow control apparatus of hydraulic pump for excavators Download PDF

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Publication number
KR100640538B1
KR100640538B1 KR1020020085681A KR20020085681A KR100640538B1 KR 100640538 B1 KR100640538 B1 KR 100640538B1 KR 1020020085681 A KR1020020085681 A KR 1020020085681A KR 20020085681 A KR20020085681 A KR 20020085681A KR 100640538 B1 KR100640538 B1 KR 100640538B1
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South Korea
Prior art keywords
pump
valve
pressure
flow control
pilot
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KR1020020085681A
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Korean (ko)
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KR20040059118A (en
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이민희
문병춘
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현대중공업 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
    • E02F9/2221—Control of flow rate; Load sensing arrangements
    • E02F9/2225—Control of flow rate; Load sensing arrangements using pressure-compensating valves
    • 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
    • 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
    • E02F9/2292—Systems with two or more pumps

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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)
  • Fluid-Pressure Circuits (AREA)
  • Operation Control Of Excavators (AREA)

Abstract

본 발명은 굴삭기 유압펌프 유량제어장치에 관한 것이며, 그 목적은 장비의 비작업시 네가티브 압력이 펌프의 사판각을 최소로 유지시킬 수 있도록 보상함으로써 연료의 낭비를 방지할 수 있는 굴삭기 유압펌프 유량제어장치를 제공함에 있다.The present invention relates to an excavator hydraulic pump flow control device, the purpose of which is to control the excavator hydraulic pump flow control to prevent the waste of fuel by compensating the negative pressure to keep the swash plate angle of the pump to the minimum when the equipment is not in operation In providing a device.

본 발명은 엔진회전수가 일정 회전수 이하가 되거나, 작업휴지상태를 CPU가 판단하여 오토 아이들(AUTO IDLE)로 엔진회전수를 낮추게 되면 CPU는 솔레노이드 밸브를 작동하여 파일럿 기어펌프에서 토출되는 파일럿 압유를 이용하여 네가티브 압력을 형성해 줌으로써 펌프의 최소사판각을 유지할 수 있는 굴삭기 유압펌프 유량제어장치에 관한 것을 그 기술적 요지로 한다.
According to the present invention, when the engine speed is lower than the predetermined speed or the CPU determines the work stop state and lowers the engine speed by AUTO IDLE, the CPU operates the solenoid valve to discharge the pilot pressure oil discharged from the pilot gear pump. The technical gist of the excavator hydraulic pump flow control device that can maintain the minimum swash plate angle of the pump by forming a negative pressure by using the technical gist.

솔레노이드 밸브, 양방향 셔틀밸브, 파일럿 기어펌프, 네가티브 라인, 엔진회전수Solenoid Valve, Bidirectional Shuttle Valve, Pilot Gear Pump, Negative Line, Engine Speed

Description

굴삭기 유압펌프 유량제어장치{Flow control apparatus of hydraulic pump for excavators} Flow control apparatus of hydraulic pump for excavators             

도 1 은 본 발명에 따른 유압 회로도1 is a hydraulic circuit diagram according to the present invention

도 2 는 종래의 굴삭기 유압 회로도
2 is a conventional excavator hydraulic circuit diagram

<도면의 주요부분에 대한 부호의 설명> <Description of the symbols for the main parts of the drawings>

(1) : 메인펌프(Main Pump)(1): Main Pump

(2) : 파일럿 기어펌프(Pilot Gear Pump)(2): Pilot Gear Pump

(3) : 엔진(Engine)(3): Engine

(4) : 솔레노이드 감압밸브(Electronic Proportional Pressure Reducing Valve)(4): Electronic Proportional Pressure Reducing Valve

(5) : CPU(5): CPU

(6) : 작업장치(Attachment)(6): Attachment

(7) : 컨트롤밸브(Control Valve)(7): Control Valve

(8) : 릴리프밸브(Relief Valve) (8): Relief Valve                 

(9) : 솔레노이드 밸브(9): Solenoid Valve

(10) : 양방향 셔틀밸브(10): Bidirectional Shuttle Valve

(11) : 바이패스 라인(11): bypass line

(12) : 네가티브 라인
12: negative line

본 발명은 굴삭기 유압펌프 유량제어장치에 관한 것으로, 보다 상세하게는 유압을 동력원으로 주로 사용하는 건설기계 중 굴삭기 펌프의 유량 제어시스템의 활용도를 향상시킨 굴삭기 유량펌프 유량제어장치에 관한 것이다.
The present invention relates to an excavator hydraulic pump flow control device, and more particularly to an excavator flow pump flow control device for improving the utilization of the flow control system of the excavator pump of the construction machinery mainly using the hydraulic power as a power source.

종래의 가변 유량형 유압펌프는 솔레노이드 감압밸브를 이용하여 엔진의 부하를 감지함으로서 펌프의 마력을 제어하는 방식과, 컨트롤밸브의 네가티브 라인에서 오는 압력에 의해 펌프의 사판각을 조절하는 네가티브 컨트롤방식의 두가지 방식으로 펌프 유량을 제어하고 있다.Conventional variable flow type hydraulic pump uses the solenoid pressure reducing valve to control the horsepower of the pump by sensing the load of the engine and the negative control type to adjust the swash plate angle by the pressure from the negative line of the control valve. The pump flow is controlled in two ways.

이중 네가티브 컨트롤방식은 도 2에 도시된 바와 같이 작동유를 공급하는 메인펌프(1)와, 상기 메인펌프(1)에서 공급되는 작동유의 방향을 제어하는 컨트롤밸브(7)와, 상기 컨트롤밸브(7)에 의해 작동하는 작업장치(6)와, 상기 컨트롤밸브(7)에서 나가는 작동유로 네가티브 압력을 형성시키기 위한 릴리프밸브(8)와, 파일럿 압력을 토출하는 파일럿 기어펌프(2)와, 엔진(3)의 부하에 따라 펌프의 사판각을 제어하기 위한 솔레노이드 감압밸브(4)와, 엔진(3)의 부하상태를 감지하여 솔레노이드 감압밸브(4)를 제어하는 CPU(5)로 구성되었다.As shown in FIG. 2, the dual negative control method includes a main pump 1 for supplying hydraulic oil, a control valve 7 for controlling the direction of the hydraulic oil supplied from the main pump 1, and the control valve 7. ), A work device 6 operated by the above, a relief valve 8 for forming negative pressure with the working oil exiting from the control valve 7, a pilot gear pump 2 for discharging pilot pressure, and an engine ( 3) a solenoid pressure reducing valve 4 for controlling the swash plate angle of the pump according to the load of 3), and a CPU 5 for controlling the solenoid pressure reducing valve 4 by detecting a load state of the engine 3.

이와 같이 구성된 네가티브 컨트롤방식은 파일럿 기어펌프(2)에서 나온 파일럿 압력이 솔레노이드 감압밸브(4)를 거치게 되며, 솔레노이드 감압밸브(4)는 CPU(5)로부터 검출된 엔진(3)의 부하량에 따라 솔레노이드 감압밸브(4)에서 나가는 2차압력을 조정하여 펌프의 사판각을 조절하게 되며, 장비가 작업조건에 있을 시에는 네가티브 압력이 거의 0이 되므로 엔진(3)의 부하량에 따라 펌프의 유량이 조절되나, 엔진(3) 회전수가 낮은 비작업시에는 네가티브 압력이 낮아지게 되므로 펌프의 사판각이 최소가 되지 않아 비작업시 불필요한 연료를 소모하게 되는 문제점이 발생되었다.
In the negative control method configured as described above, the pilot pressure from the pilot gear pump 2 passes through the solenoid pressure reducing valve 4, and the solenoid pressure reducing valve 4 is loaded according to the load of the engine 3 detected from the CPU 5. The swash plate angle of the pump is adjusted by adjusting the secondary pressure exiting the solenoid pressure reducing valve (4) .When the equipment is in working condition, the negative pressure becomes almost zero, so the flow rate of the pump depends on the load of the engine (3). However, since the negative pressure is lowered during non-working when the engine speed is low, the swash plate angle of the pump is not minimized, causing unnecessary fuel consumption during non-working.

본 발명은 상기와 같은 종래의 문제점을 해결하기 위하여 안출되는 것으로, 그 목적은 장비의 비작업시 네가티브 압력이 펌프의 사판각을 최소로 유지시킬 수 있도록 보상함으로써 연료의 낭비를 방지할 수 있는 굴삭기 유압펌프 유량제어장치를 제공함에 있다.
The present invention has been made to solve the above-mentioned conventional problems, an object of the excavator to prevent the waste of fuel by compensating to maintain the swash plate angle of the pump to the minimum when the equipment is not working It is to provide a hydraulic pump flow control device.

상기와 같은 본 발명의 목적은 엔진회전수가 일정 회전수 이하가 되거나, 작업휴지상태를 CPU가 판단하여 오토 아이들(AUTO IDLE)로 엔진회전수를 낮추게 되면 CPU는 솔레노이드 밸브를 작동하여 파일럿 기어펌프에서 토출되는 파일럿 압유를 이용하여 네가티브 압력을 형성해 줌으로써 펌프의 최소사판각을 유지할 수 있는 굴삭기 유압펌프 유량제어장치를 제공함으로써 달성된다.
The object of the present invention as described above is that when the engine speed is lower than the predetermined speed, or the CPU judges the work stop state to lower the engine speed by the auto idle (AUTO IDLE), the CPU operates the solenoid valve in the pilot gear pump It is achieved by providing an excavator hydraulic pump flow control device that can maintain the minimum swash plate angle of the pump by forming a negative pressure using the discharged pilot pressure oil.

이하, 본 발명의 실시예를 첨부도면과 연계하여 상세히 설명하면 다음과 같다.Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

도 1 은 본 발명의 구성을 나타낸 유압회로도를 도시한 것으로, 본 발명은 작동유를 공급하는 메인펌프(1)와, 상기 메인펌프(1)에서 공급되는 작동유의 방향을 제어하는 컨트롤밸브(7)와, 상기 컨트롤밸브(7)에 의해 작동하는 작업장치(6)와, 상기 컨트롤밸브(7)에서 나가는 작동유로 네가티브 압력을 형성시키기 위한 릴리프밸브(8)와, 파일럿 압력을 토출하는 파일럿 기어펌프(2)와, 엔진(3)의 부하에 따라 펌프의 사판각을 제어하기 위한 솔레노이드 감압밸브(4)와, 엔진(3)의 부하상태를 감지하여 솔레노이드 감압밸브(4)를 제어하는 CPU(5)로 구성된 굴삭기 유압펌프 유량제어장치에 있어서, 상기 컨트롤밸브(7)에서 토출되는 압유를 탱크로 전달하는 바이패스 라인(11)과 메인펌프(1)를 연결하여 네가티브 압력을 형성하는 네가티브 라인(12)상에 양방향 셔틀밸브(10)를 설치하여 CPU(5)에 의해 작동하는 솔레노이드 밸브(9)를 연결하고, 상기 솔레노이드 밸브(9)와 파일럿 기어펌프(2)를 연결하여 파일럿 기어펌프(2)에서 토출된 파일럿 압력이 네가티브 압력을 보상해줄 수 있도록 하며, 상기 양방향 셔틀밸브(10)의 출구측을 메인펌프(1)에 연결한 것으 로 구성되었다.Figure 1 shows a hydraulic circuit diagram showing the configuration of the present invention, the present invention is a main pump (1) for supplying the operating oil and a control valve (7) for controlling the direction of the operating oil supplied from the main pump (1) And a work device 6 operated by the control valve 7, a relief valve 8 for forming negative pressure with the working oil exiting from the control valve 7, and a pilot gear pump for discharging pilot pressure. (2), the solenoid pressure reducing valve 4 for controlling the swash plate angle of the pump according to the load of the engine 3, and the CPU for controlling the solenoid pressure reducing valve 4 by detecting the load state of the engine 3 ( In the excavator hydraulic pump flow control device consisting of 5), the negative line connecting the bypass line 11 and the main pump (1) for transmitting the pressure oil discharged from the control valve 7 to the tank to form a negative pressure 2-way shuttle bell on (12) (10) to connect the solenoid valve (9) operated by the CPU (5), the solenoid valve (9) and the pilot gear pump (2) by connecting the pilot pressure discharged from the pilot gear pump (2) To compensate for this negative pressure, it was configured to connect the outlet side of the two-way shuttle valve (10) to the main pump (1).

상기 양방향 셔틀밸브(10)는 한쪽 입력측이 네가티브 라인(12)과 연결되고, 나머지 입력측이 솔레노이드 밸브(9)의 토출구에 연결되며, 출구측은 상술한 바와 같이 메인펌프(1)와 연결되었다.The bidirectional shuttle valve 10 has one input side connected to the negative line 12, the other input side connected to the discharge port of the solenoid valve 9, and the outlet side connected to the main pump 1 as described above.

한편, 양방향 셔틀밸브(10)에 토출구가 연결된 솔레노이드 밸브(9)는 입력측이 파일럿 기어펌프(2)에 연결되어 파일럿 기어펌프(2)로부터 토출되는 파일럿 압유를 CUP의 제어에 의해 메인펌프(1)로 공급함으로써 부족한 네가티브 압력을 보상해주도록 구성되었다.Meanwhile, the solenoid valve 9 having a discharge port connected to the bidirectional shuttle valve 10 has an input side connected to the pilot gear pump 2 so that the pilot pressure oil discharged from the pilot gear pump 2 is controlled by the CUP. ) To compensate for the negative pressures that are lacking.

상기와 같이 구성된 본 발명은 작업장치(6)가 작동하지 않는 비작업시에는 컨트롤밸브(7)가 중립위치로서 메인펌프(1)에서 토출되는 압유는 바이패스 라인(11)에 설치된 릴리프밸브(8)를 거쳐 네가티브 라인(12)에 연결된 양방향 셔틀밸브(10)로 전달되는 한편, 솔레노이드 밸브(9)의 스풀이 닫혀있으므로 네가티브 라인(12)을 통해 전달된 압유는 메인펌프(1)로 전달되고, 이때 CPU(5)는 엔진(3) 회전수를 감지하여 엔진(3) 회전수가 일정 회전수 이하가 되면 솔레노이드 밸브(9)의 스풀을 개방시킴으로 파일럿 압력이 네가티브 압력을 보상해 주어 펌프의 사판각을 최소화 할 수 있게 되는 것이다.According to the present invention configured as described above, when the work device 6 is not operated, the control valve 7 is discharged from the main pump 1 as a neutral position, and the relief valve installed in the bypass line 11 ( 8) to the bi-directional shuttle valve 10 connected to the negative line 12, while the spool of the solenoid valve 9 is closed, the pressure oil delivered through the negative line 12 to the main pump (1) In this case, the CPU 5 detects the engine 3 rotational speed and opens the spool of the solenoid valve 9 when the engine 3 rotational speed becomes lower than the predetermined rotational speed, thereby compensating for the negative pressure of the pump. The swash plate angle can be minimized.

또한, 장비의 작업휴지상태시 CUP가 이를 감지하여 엔진(3)의 회전수를 낮추게 되면, 상기와 동일하게 솔레노이드 밸브(9)를 작동하여 네가티브 압력을 보상해 줄 수 있게 되는 것이다.
In addition, if the CUP detects this when the work stop state of the equipment lowers the number of revolutions of the engine (3), it is possible to compensate for the negative pressure by operating the solenoid valve (9) as described above.

본 발명은 상술한 특정의 바람직한 실시예에 한정되지 아니하며, 청구범위에서 청구하는 본 발명의 요지를 벗어남이 없이 당해 발명이 속하는 기술분야에서 통상의 지식을 가진 자라면 누구든지 다양한 변형실시가 가능한 것은 물론이고, 그와 같은 변경은 청구범위 기재의 범위 내에 있게 된다.
The present invention is not limited to the above-described specific preferred embodiments, and various modifications can be made by any person having ordinary skill in the art without departing from the gist of the present invention claimed in the claims. Of course, such changes will fall within the scope of the claims.

상술한 바와 같이 본 발명은 장비의 비작업시 파일럿 기어펌프에서 토출되는 파일럿 압유를 이용하여 부족한 네가티브 압력을 CPU 제어에 의해 보상할 수 있도록 솔레노이드 밸브와 양방향 셔틀밸브를 설치하여 비작업시 불필요하게 소모되는 연료를 감소시킬 수 있는 효과가 있는 것이다.









As described above, the present invention uses a solenoid valve and a two-way shuttle valve to compensate for the negative pressure insufficient by using the pilot pressure oil discharged from the pilot gear pump when the equipment is not in operation. There is an effect that can reduce the fuel.









Claims (1)

작동유를 공급하는 메인펌프(1)와, 상기 메인펌프(1)에서 공급되는 작동유의 방향을 제어하는 컨트롤밸브(7)와, 상기 컨트롤밸브(7)에 의해 작동하는 작업장치(6)와, 상기 컨트롤밸브(7)에서 나가는 작동유로 네가티브 압력을 형성시키기 위한 릴리프밸브(8)와, 파일럿 압력을 토출하는 파일럿 기어펌프(2)와, 엔진(3)의 부하에 따라 펌프의 사판각을 제어하기 위한 솔레노이드 감압밸브(4)와, 엔진(3)의 부하상태를 감지하여 솔레노이드 감압밸브(4)를 제어하는 CPU(5)로 구성된 굴삭기 유압펌프 유량제어장치에 있어서,A main pump (1) for supplying hydraulic oil, a control valve (7) for controlling the direction of the hydraulic oil supplied from the main pump (1), a working device (6) operated by the control valve (7), The swash plate angle of the pump is controlled in accordance with the load of the engine 3, the relief valve 8 for forming the negative pressure as the working oil exiting the control valve 7, the pilot gear pump 2 for discharging the pilot pressure, and the engine 3 In the excavator hydraulic pump flow control device composed of a solenoid pressure reducing valve 4 and a CPU (5) for sensing the load state of the engine (3) to control the solenoid pressure reducing valve (4), 상기 컨트롤밸브(7)에서 토출되는 압유를 탱크로 전달하는 바이패스 라인(11)과 메인펌프(1)를 연결하여 네가티브 압력을 형성하는 네가티브 라인(12)상에 양방향 셔틀밸브(10)의 한쪽 입구측을 연결 설치하고, 나머지 입구측에 CPU(5)에 의해 작동하는 솔레노이드 밸브(9)를 연결 설치하며, 상기 솔레노이드 밸브(9)와 파일럿 기어펌프(2)를 연결하여 파일럿 기어펌프(2)에서 토출된 파일럿 압력이 네가티브 압력을 보상해줄 수 있도록 함과 동시에 양방향 셔틀밸브(10)의 출구측을 메인펌프(1)에 연결하여 구성된 것을 특징으로 하는 굴삭기 유압펌프 유량제어장치.One side of the two-way shuttle valve 10 on the negative line 12 connecting the bypass line 11 and the main pump 1 to transfer the pressure oil discharged from the control valve 7 to the tank to form a negative pressure Connect the inlet side and install the solenoid valve 9 operated by the CPU 5 on the other inlet side, and connect the solenoid valve 9 and the pilot gear pump 2 to the pilot gear pump 2 Excavator hydraulic pressure discharged from the) to compensate for the negative pressure and at the same time the hydraulic pump flow control device, characterized in that configured by connecting the outlet side of the two-way shuttle valve (10) to the main pump (1).
KR1020020085681A 2002-12-28 2002-12-28 Flow control apparatus of hydraulic pump for excavators KR100640538B1 (en)

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KR100998613B1 (en) * 2008-11-06 2010-12-07 볼보 컨스트럭션 이큅먼트 에이비 hydraulic system of construction equipment
WO2012030003A1 (en) * 2010-09-02 2012-03-08 볼보 컨스트럭션 이큅먼트 에이비 Hydraulic circuit for construction equipment
CN102733444A (en) * 2012-06-29 2012-10-17 山河智能装备股份有限公司 Boarding rotation starting non-overflowing system
KR102045075B1 (en) 2018-09-27 2019-11-14 썬 하이드로릭스 코리아 주식회사 Electronic control valve blocks for main control valves of construction machinery

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KR101301234B1 (en) * 2007-12-06 2013-08-29 볼보 컨스트럭션 이큅먼트 에이비 pressure compensation hydraulic circuit of control engine revolution of excavator
KR101683317B1 (en) * 2008-12-24 2016-12-07 두산인프라코어 주식회사 Device for hydraulic pump control in heavy equipment
KR101328847B1 (en) * 2009-07-17 2013-11-13 현대중공업 주식회사 Negative Flow Control System for Mini Excavator

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Publication number Priority date Publication date Assignee Title
KR100998613B1 (en) * 2008-11-06 2010-12-07 볼보 컨스트럭션 이큅먼트 에이비 hydraulic system of construction equipment
WO2012030003A1 (en) * 2010-09-02 2012-03-08 볼보 컨스트럭션 이큅먼트 에이비 Hydraulic circuit for construction equipment
CN103080566A (en) * 2010-09-02 2013-05-01 沃尔沃建造设备有限公司 Hydraulic circuit for construction equipment
US9228599B2 (en) 2010-09-02 2016-01-05 Volvo Construction Equipment Ab Hydraulic circuit for construction equipment
CN102733444A (en) * 2012-06-29 2012-10-17 山河智能装备股份有限公司 Boarding rotation starting non-overflowing system
CN102733444B (en) * 2012-06-29 2014-09-03 山河智能装备股份有限公司 Boarding rotation starting non-overflowing system
KR102045075B1 (en) 2018-09-27 2019-11-14 썬 하이드로릭스 코리아 주식회사 Electronic control valve blocks for main control valves of construction machinery

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