KR20070105424A - The hydraulic excavators with energy-saving hydraulic boom cylinders - Google Patents

The hydraulic excavators with energy-saving hydraulic boom cylinders Download PDF

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Publication number
KR20070105424A
KR20070105424A KR1020060037485A KR20060037485A KR20070105424A KR 20070105424 A KR20070105424 A KR 20070105424A KR 1020060037485 A KR1020060037485 A KR 1020060037485A KR 20060037485 A KR20060037485 A KR 20060037485A KR 20070105424 A KR20070105424 A KR 20070105424A
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South Korea
Prior art keywords
boom
cylinder
main
hydraulic
cylinder part
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KR1020060037485A
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Korean (ko)
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곽창환
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현대중공업 주식회사
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Priority to KR1020060037485A priority Critical patent/KR20070105424A/en
Publication of KR20070105424A publication Critical patent/KR20070105424A/en

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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
    • 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
    • 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
    • F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
    • F15B1/02—Installations or systems with accumulators
    • 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
    • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/08—Characterised by the construction of the motor unit
    • F15B15/14—Characterised by the construction of the motor unit of the straight-cylinder type
    • F15B15/1423—Component parts; Constructional details
    • F15B15/1428—Cylinders
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60Y—INDEXING SCHEME RELATING TO ASPECTS CROSS-CUTTING VEHICLE TECHNOLOGY
    • B60Y2200/00—Type of vehicle
    • B60Y2200/40—Special vehicles
    • B60Y2200/41—Construction vehicles, e.g. graders, excavators
    • B60Y2200/412—Excavators
    • 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

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Operation Control Of Excavators (AREA)
  • Fluid-Pressure Circuits (AREA)

Abstract

A hydraulic excavator having an energy-saving hydraulic boom cylinder is provided to maintain high work efficiency while using less energy by interlocking an auxiliary cylinder part distributing compression loads exerted on the main cylinder part with a main cylinder part. A hydraulic excavator comprises a body part, a driver seat, a running unit, a bucket, an arm, a boom, and a boom cylinder for driving the boom. The driver seat is disposed on a front side of the body part, and the running unit is disposed on a lower side of the body part. The boom cylinder comprises a main cylinder part(21) and an auxiliary cylinder part(25) disposed adjacent to the main cylinder part and interlocking with the main cylinder part so as to distribute compression loads exerted on the main cylinder part. The auxiliary cylinder part is connected to an accumulator(27) to make a hydraulic line independent of the main cylinder part.

Description

에너지 절감용 붐 실린더를 구비한 굴삭기{The hydraulic excavators with energy-saving hydraulic boom cylinders}The hydraulic excavators with energy-saving hydraulic boom cylinders

도 1은 본 발명의 일 실시예에 따른 붐 실린더 굴삭기를 나타내는 사시도,1 is a perspective view showing a boom cylinder excavator according to an embodiment of the present invention,

도 2는 본 발명에 일 실시예에 따른 붐 실린더 굴삭기에 설치된 유압회로도를 나타내는 개략도이다.Figure 2 is a schematic diagram showing a hydraulic circuit diagram installed in the boom cylinder excavator according to an embodiment of the present invention.

*도면 내 주요부분에 대한 부호설명** Description of Signs for Main Parts in Drawings *

20: 붐 실린더 21: 메인실린더부20: boom cylinder 21: main cylinder portion

23: 오리피스 24: 메인콘트롤밸브부23: Orifice 24: Main control valve unit

25: 보조실린더부 27: 어큐뮬레이터25: auxiliary cylinder 27: accumulator

본 발명은 굴삭기에 관한 것으로, 특히 에너지 절감용 붐 실린더를 구비한 굴삭기에 관한 것이다.The present invention relates to an excavator, in particular to an excavator having an energy saving boom cylinder.

일반적으로 굴삭기는 전면에 설치된 붐과 이 붐의 선단에 설치된 버켓을 사용하여 굴삭작업 등을 수행하는 중장비로서, 버켓을 지면에 대고 압력을 가하기 위 해서는 이 버켓이 설치되어 있는 붐을 효과적으로 작동시킬 수 있어야 한다.In general, an excavator is a heavy equipment that performs excavation work using the boom installed at the front and the bucket installed at the tip of the boom, and can effectively operate the boom equipped with this bucket to apply pressure to the ground. Should be

이와 같은 붐의 상하 구동을 담당하는 붐 실린더는 붐의 인장 및 수축 시 유압을 사용하며, 특히 수축 시에는 메인콘트롤밸브 내에 있는 오리피스의 유량조절기능을 통해 붐의 하강속도를 조절하였다. 그런데, 상기 오리피스로 인해 붐의 하강 시 필요이상의 유압을 요구하게 되었다.The boom cylinder, which is responsible for the up and down driving of the boom, uses hydraulic pressure when the boom is tensioned and contracted, and in particular, when the contraction, the boom lowering speed is adjusted through the flow control function of the orifice in the main control valve. However, the orifice required more hydraulic pressure than necessary when the boom was lowered.

한편, 굴삭기에 채용된 유압라인은 디젤엔진을 사용하여 굴삭기 내에서 설치된 유압펌프를 작동시키는데, 상기 오리피스로 인해 발생하는 유압조건을 만족시키기 위해서는 디젤엔진의 출력을 높여야 하므로, 이에 따라 연료의 소모량이 증가하는 것은 물론, 디젤엔진으로부터 다량 배출되는 배기가스로 인해 대기오염을 유발하는 문제가 있었다.On the other hand, the hydraulic line employed in the excavator operates a hydraulic pump installed in the excavator using a diesel engine, and in order to satisfy the hydraulic conditions generated by the orifice, the output of the diesel engine must be increased, so that the consumption of fuel As well as increasing, there was a problem causing air pollution due to the large amount of exhaust gas discharged from the diesel engine.

상기한 문제점을 해결하기 위해 본 발명은, 평소보다 적은 에너지를 사용하여 평소와 같은 작업율을 유지할 수 있는 에너지 절감용 붐 실린더를 구비한 굴삭기를 제공하는 데 있다.In order to solve the above problems, the present invention is to provide an excavator having an energy-saving boom cylinder that can maintain the work rate as usual by using less energy than usual.

상기한 목적을 달성하기 위해 본 발명은 본체와, 본체 전방에 배치된 운전석과, 본체 하부에 배치된 주행수단과, 버켓, 암, 붐 및 붐을 구동하기 위한 붐 실린더를 구비한 굴삭기에 있어서, 상기 붐 실린더는 메인실린더부; 및, 상기 메인실린 더부에 가해지는 압축하중을 분산시킬 수 있도록 상기 메인실린더부에 인접하게 배치되어 상기 메인실린더부와 연동하는 보조실린더부;를 포함하는 것을 특징으로 하는 에너지 절감용 붐 실린더를 구비한 굴삭기를 제공한다.In order to achieve the above object, the present invention provides an excavator having a main body, a driver's seat disposed in front of the main body, a traveling means disposed below the main body, and a boom cylinder for driving the bucket, the arm, the boom and the boom, The boom cylinder is a main cylinder portion; And an auxiliary cylinder portion disposed adjacent to the main cylinder portion so as to distribute the compressive load applied to the main cylinder portion and interlocked with the main cylinder portion. Provide one excavator.

상기 보조실린더부는 상기 메인실린더부와 독립적인 유압라인을 이루도록 어큐뮬레이터와 연결된다.The auxiliary cylinder part is connected to the accumulator to form a hydraulic line independent of the main cylinder part.

상기 메인실린더부는 붐의 승,하강 구동을 위해 인장 및 수축 시 유압이 작동하는 복동실린더이고, 상기 보조실린더부는 인장 시 유압이 작동하는 단동실린더로 이루어진다.The main cylinder portion is a double-acting cylinder that the hydraulic pressure is actuated when the tension and contraction to drive the boom up, down, and the auxiliary cylinder is made of a single-acting cylinder actuated by the hydraulic pressure when the tension.

이하, 첨부한 도면을 참조하여 본 발명에 따른 에너지 절감용 붐 실린더를 구비한 굴삭기의 구성을 상세히 설명하면 다음과 같다.Hereinafter, the configuration of an excavator equipped with an energy saving boom cylinder according to the present invention will be described in detail with reference to the accompanying drawings.

첨부된 도 1은 본 발명의 일 실시예에 따른 붐 실린더 굴삭기를 나타내는 사시도이고, 도 2는 본 발명의 일 실시예에 따른 붐 실린더 굴삭기에 설치된 유압회로도를 나타내는 개략도이다.1 is a perspective view showing a boom cylinder excavator according to an embodiment of the present invention, Figure 2 is a schematic diagram showing a hydraulic circuit diagram installed in the boom cylinder excavator according to an embodiment of the present invention.

본 발명의 일 실시예에 따른 굴삭기(1)는 도 1과 같이, 본체(2)와, 본체(2) 전방에 배치된 운전석(3)과, 본체(2) 하부에 배치된 주행수단(4) 및, 작업장치(10)를 포함한다.Excavator 1 according to an embodiment of the present invention, as shown in Figure 1, the main body 2, the driver's seat 3 disposed in front of the main body 2, and the traveling means 4 disposed under the main body 2 And a work device 10.

작업장치(10)는 일단이 본체(2)에 상하로 선회가능하게 결합된 붐(11)과, 붐(11)의 타단이 일단이 힌지결합된 암(12)과, 붐(11)과 암(12)을 상호 연결하는 암 실린더(13)와, 암(12)의 타단에 힌지결합된 버킷(14)과, 버켓실린더(15), 컨트 롤링크(16) 및 컨트롤로드(17)를 포함한다.The work device 10 includes a boom 11 whose one end is pivotally coupled vertically to the main body 2, an arm 12 having one end hinged to the other end of the boom 11, a boom 11 and an arm. An arm cylinder (13) interconnecting (12), a bucket (14) hinged to the other end of the arm (12), a bucket cylinder (15), a control link (16), and a control rod (17). do.

또한, 작업장치(10)는 붐(11)의 승하강을 담당하는 붐 실린더(20)를 구비하며, 이러한 붐 실린더(20)는 서로 연동하는 메인실린더부(21)와 보조실린더부(25)를 포함한다.In addition, the work device 10 is provided with a boom cylinder 20 that is responsible for raising and lowering the boom 11, the boom cylinder 20 is the main cylinder portion 21 and the auxiliary cylinder portion 25 to interlock with each other. It includes.

도 2와 같이, 메인실린더부(21)는 오일이 장입된 메인컨트롤밸브부(24)로부터 유압을 받아 붐(11)의 승하강에 대응하여 인장과 수축을 행하는 복동실린더이다. 이 경우, 메인컨트롤밸브부(24) 내에는 붐(11)의 하강속도를 제어하기 위한 오리피스(23)가 설치되며, 이 오리피스(23)는 메인실린더부(21)에서 메인컨트롤밸브부(24)로 빠져나오는 유량을 조절한다.As shown in FIG. 2, the main cylinder part 21 is a double-acting cylinder that receives hydraulic pressure from the main control valve part 24 in which oil is loaded and performs tension and contraction in response to the lifting and lowering of the boom 11. In this case, an orifice 23 for controlling the lowering speed of the boom 11 is installed in the main control valve part 24, and the orifice 23 is the main control valve part 24 in the main cylinder part 21. To adjust the flow rate.

보조실린더부(25)는 어큐뮬레이터(27)와 연결되어 있어 메인실린더부(21)와 독립적인 유압라인을 구성한다. 이러한 보조실린더부(25)는 붐의 인장 시에만 어큐뮬레이터(27)로부터 유압이 작용하는 단동실린더이다.The auxiliary cylinder portion 25 is connected to the accumulator 27 to form a hydraulic line independent from the main cylinder portion 21. The auxiliary cylinder 25 is a single-acting cylinder in which hydraulic pressure acts from the accumulator 27 only when the boom is tensioned.

이 경우, 어큐뮬레이터(27)는 메인실린더부(21)에 가해지는 압축하중을 보조실린더부(25)로 분산시켜 메인실린더부(21)에 걸리는 부하를 줄일 수 있도록, 상기 작업장치(10)에 대한 전체무게의 소정 부분 예를 들면 2/3 정도의 무게를 지지할 수 있도록 자체 압력을 세팅할 수 있다.In this case, the accumulator 27 distributes the compressive load applied to the main cylinder portion 21 to the auxiliary cylinder portion 25 so as to reduce the load on the main cylinder portion 21. It is possible to set its own pressure so as to support a certain part of the total weight, for example about 2/3 of the weight.

이와 같이 구성된 본 발명의 일 실시예에 따른 에너지 절감용 붐 실린더를 구비한 굴삭기의 작용을 설명하면 다음과 같다.Referring to the operation of the excavator equipped with an energy saving boom cylinder according to an embodiment of the present invention configured as described above are as follows.

굴삭기의 굴삭작업 시 버켓(14)에 작업물질을 담기 위해 붐(11)을 상승시키는 덤핑동작의 경우, 보조실린더부(25)에 연결된 어큐뮬레이터(13)는 작업장치(10) 무게의 일정부분을 지지할 수 있도록 압력이 세팅이 가능하므로, 종래의 붐 실린더 보다 적은 힘을 사용하면서 붐(11)을 승강시킬 수 있다.In the case of a dumping operation in which the boom 11 is raised to contain the work material in the bucket 14 during the excavation work of the excavator, the accumulator 13 connected to the auxiliary cylinder 25 has a certain portion of the weight of the work device 10. Since the pressure can be set so that it can support, the boom 11 can be raised and lowered using less force than the conventional boom cylinder.

한편, 덤핑 후 붐(11)을 하강시키는 경우, 메인콘트롤밸브부(24) 내에 배치된 오리피스(23)의 유량조절기능으로 인해 발생하는 압력에 비례하여 유량이 증가하게 되므로, 이때 오리피스(23)에 가해지는 압력은 작업장치(10)의 무게에 의해 발생하는 압력보다 높아진다. 이 경우, 보조실린더부(25)는 붐(11)의 하강속도를 구현하기 위해 만들어진 임의의 저항을 극복할 수 있는 역할을 한다. 따라서, 오리피스(23)에서 유량을 증가시키더라도 붐(11)의 원하는 하강속도를 구현할 수 있다.On the other hand, when the boom 11 is lowered after dumping, the flow rate is increased in proportion to the pressure generated by the flow control function of the orifice 23 disposed in the main control valve unit 24, the orifice 23 at this time The pressure applied to the pressure is higher than the pressure generated by the weight of the working device (10). In this case, the auxiliary cylinder portion 25 serves to overcome any resistance made to implement the falling speed of the boom 11. Therefore, even if the flow rate is increased at the orifice 23, the desired descending speed of the boom 11 can be achieved.

상기한 본 발명에 있어서는, 굴삭기의 붐을 양측에서 각각 지지하며 상하로 구동하는 실린더를 메인실린더부 이외에 메인실린더부에 가해지는 압축하중을 분산시키기 위한 보조실린더부를 메인실린더부와 연동하도록 메인실린더부에 일측에 평행하게 배치함에 따라, 메인실린더부 및 보조실린더부를 함께 운용하여 종래에 소비한 에너지보다 적은 에너지를 사용하여 종래와 동일한 작업을 행할 수 있는 이점이 있다.In the present invention described above, the main cylinder portion so as to cooperate with the main cylinder portion for dispersing the compression load applied to the main cylinder portion in addition to the main cylinder portion for the cylinders that support the boom of the excavator on both sides and drive up and down, respectively By arranging parallel to one side, there is an advantage that the same operation as in the prior art can be performed using less energy than conventionally consumed by operating the main cylinder portion and the auxiliary cylinder portion together.

또한, 붐 실린더와 같은 유압장치는 굴삭기에 탑재된 디젤엔진을 사용하여 구동함에 따라, 붐의 상하운동 시 소모되는 에너지를 줄일 수 있으므로, 고유가 시대에 유류절감 및 외부로 배출되는 배출가스를 감소시켜 대기오염을 줄일 수 있다.In addition, the hydraulic device such as the boom cylinder is driven by using a diesel engine mounted on the excavator, it can reduce the energy consumed during the vertical movement of the boom, thereby reducing oil and emissions to the outside in the high oil price era Air pollution can be reduced.

이상에서는 본 발명을 특정의 바람직한 실시예를 예를 들어 도시하고 설명하 였으나, 본 발명은 상기한 실시예에 한정되지 아니하며 본 발명의 정신을 벗어나지 않는 범위 내에서 당해 발명이 속하는 기술분야에서 통상의 지식을 가진 자에 의해 다양한 변경과 수정이 가능할 것이다.While the present invention has been illustrated and described with reference to certain preferred embodiments, the present invention is not limited to the above-described embodiments, and the present invention is not limited to the above-described embodiments. Many changes and modifications will be possible to those skilled in the art.

Claims (3)

본체와, 본체 전방에 배치된 운전석과, 본체 하부에 배치된 주행수단과, 버켓, 암, 붐 및 붐을 구동하기 위한 붐 실린더를 구비한 굴삭기에 있어서,In an excavator equipped with a main body, a driver's seat disposed in front of the main body, a traveling means disposed below the main body, and a boom cylinder for driving a bucket, an arm, a boom, and a boom, 상기 붐 실린더는The boom cylinder 메인실린더부; 및,Main cylinder unit; And, 상기 메인실린더부에 가해지는 압축하중을 분산시킬 수 있도록 상기 메인실린더부에 인접하게 배치되어 상기 메인실린더부와 연동하는 보조실린더부;를 포함하는 것을 특징으로 하는 에너지 절감용 붐 실린더를 구비한 굴삭기.Excavator having an energy-saving boom cylinder, characterized in that it comprises; an auxiliary cylinder portion disposed adjacent to the main cylinder portion to cooperate with the main cylinder portion so as to distribute the compressive load applied to the main cylinder portion . 제1항에 있어서, 상기 보조실린더부는 상기 메인실린더부와 독립적인 유압라인을 이루도록 어큐뮬레이터와 연결된 것을 특징으로 하는 에너지 절감용 붐 실린더를 구비한 굴삭기.The excavator with an energy saving boom cylinder according to claim 1, wherein the auxiliary cylinder is connected to an accumulator to form a hydraulic line independent of the main cylinder. 제1항 또는 제2항에 있어서,The method according to claim 1 or 2, 상기 메인실린더부는 붐의 승,하강 구동을 위해 인장 및 수축 시 유압이 작동하는 복동실린더이고,The main cylinder portion is a double-acting cylinder that operates the hydraulic pressure in the tension and contraction to drive the boom up, down, 상기 보조실린더부는 인장 시 유압이 작동하는 단동실린더인 것을 특징으로 하는 에너지 절감용 붐 실린더를 구비한 굴삭기.The auxiliary cylinder is an excavator having an energy-saving boom cylinder, characterized in that the hydraulic actuation single acting cylinder when the tension.
KR1020060037485A 2006-04-26 2006-04-26 The hydraulic excavators with energy-saving hydraulic boom cylinders KR20070105424A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101532783B1 (en) * 2008-12-22 2015-06-30 두산인프라코어 주식회사 Apparatus for driving working device of construction machinery
CN110219332A (en) * 2019-05-12 2019-09-10 董志强 A kind of actuator gravity canceller of excavator
CN112431240A (en) * 2019-08-26 2021-03-02 广西柳工机械股份有限公司 Loading machine

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101532783B1 (en) * 2008-12-22 2015-06-30 두산인프라코어 주식회사 Apparatus for driving working device of construction machinery
CN110219332A (en) * 2019-05-12 2019-09-10 董志强 A kind of actuator gravity canceller of excavator
CN110219332B (en) * 2019-05-12 2024-05-28 董志强 Swing arm mechanism gravity counteracting device of excavator
CN112431240A (en) * 2019-08-26 2021-03-02 广西柳工机械股份有限公司 Loading machine

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