KR20140083118A - Method for controlling the option actuator in excavator - Google Patents

Method for controlling the option actuator in excavator Download PDF

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Publication number
KR20140083118A
KR20140083118A KR1020120151954A KR20120151954A KR20140083118A KR 20140083118 A KR20140083118 A KR 20140083118A KR 1020120151954 A KR1020120151954 A KR 1020120151954A KR 20120151954 A KR20120151954 A KR 20120151954A KR 20140083118 A KR20140083118 A KR 20140083118A
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KR
South Korea
Prior art keywords
pressure
excavator
set pressure
optional
hydraulic pump
Prior art date
Application number
KR1020120151954A
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Korean (ko)
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KR102008022B1 (en
Inventor
임현식
Original Assignee
두산인프라코어 주식회사
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Priority to KR1020120151954A priority Critical patent/KR102008022B1/en
Publication of KR20140083118A publication Critical patent/KR20140083118A/en
Application granted granted Critical
Publication of KR102008022B1 publication Critical patent/KR102008022B1/en

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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
    • 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
    • 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
    • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205—Systems with pumps
    • 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
    • F15B2211/50—Pressure control
    • F15B2211/505—Pressure control characterised by the type of pressure control means

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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)
  • Operation Control Of Excavators (AREA)

Abstract

The present invention relates to a control method for an excavator option actuator in order to control a hydraulic pressure provided to an option actuator on the front end of an excavator. More specifically, the present invention relates to a control method for an excavator option actuator in order to control the excavator option actuator using not a relief valve, but by an electronically controlled controller in order to operate the option actuator by preventing the pressure from rising above a predetermined pressure.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an excavator,

The present invention relates to a method of controlling an optional work device of an excavator for controlling an oil pressure supplied to an optional work device at an end of an excavator, and more particularly, to an excavator option work device using an electronically controlled control device, To an option work device control method for an excavator that operates the option work device by limiting the pressure to less than the set pressure of the option work device.

An excavator is a construction machine that performs various tasks in civil engineering, construction, and construction work. It is a front work device composed of a traveling body that plays a role of moving equipment, an upper revolving body which is mounted on a traveling body and rotates 360 degrees, and a boom, an arm and a bucket. .

Meanwhile, such an excavator is used by replacing a bucket, which is mainly used in excavation work, with an optional work device such as a breaker, a crusher and a shear according to the type of work.

The breaker breaks hard rocks and the like and can be driven by one-way flow of hydraulic oil. On the other hand, the crusher picks up a hard object and the shear is driven by a two-way flow of hydraulic fluid to allow cutting.

1 shows an excavator hydraulic system for an optional work device driven by a bidirectional flow of hydraulic fluid, such as, for example, a crusher or a shear.

As shown, the excavator hydraulic system includes a lever pressure sensor 10, a control device 20, an electronically controlled hydraulic pump 30, a main control valve 40, a working machine cylinder (also referred to as an attachment cylinder) 50, And a relief valve portion (60). The relief valve portion (60) includes an electron proportional control relief valve (61).

Accordingly, when the lever pressure sensor 10 senses the operation of the operation lever (not shown) and provides it to the control device 20, the control device 20 activates the electronically controlled hydraulic pump 30. The hydraulic fluid supplied from the electronically controlled hydraulic pump 30 is supplied to the working machine cylinder 50 after the bidirectional flow is controlled through the main control valve 40.

On the other hand, the hydraulic pressure supplied to the bidirectional option working device also uses some of them because the excavator limits the overall pressure specification depending on its performance. In addition, the 'set pressure' selected according to the type of the attached optional working device is fixedly supplied to the optional working device.

Further, when the work load during the provision of the set pressure through the electronically controlled hydraulic pump 30 is equal to or higher than the set pressure, or when the working cylinder 50 is at the maximum / minimum stroke position, the relief operation of the relief valve portion 60 To allow the remaining hydraulic fluid to be recovered to the tank. Therefore, the set pressure is always maintained.

However, as described above, when increasing the working load while supplying the set pressure to the optional working device, the engine torque must be always large to maintain the set pressure by the relief operation. This obviously causes a reduction in fuel consumption.

In other words, the electronically controlled hydraulic pump 30 always applies the set pressure in accordance with the selected optional working device, and when the excess pressure is generated, the residual pressure oil is recovered to the tank by using the relief valve to waste the fuel .

Especially, this waste of fuel is heavy for excavators working on the high steel or building demolition site equipped with optional two-way flow-driven operating equipment such as crusher or shear.

SUMMARY OF THE INVENTION The present invention has been proposed in order to solve the above-mentioned problems, and it is an object of the present invention to provide an excavator option working apparatus which controls an excavator option working apparatus by using an electronically controlled control apparatus instead of a relief valve, And to provide a method of controlling an optional working device of an excavator.

To this end, a method of controlling an optional work device of an excavator according to the present invention includes: a set pressure determining step of setting a pressure applied to the optional work device using an operation lever when an optional work device is attached to an excavator; A pump control step of controlling the electronically controlled hydraulic pump by limiting a maximum pressure command for the electronically controlled hydraulic pump to a set pressure or less in the control device; And a restriction releasing step of releasing the restriction that the control device is controlled to be equal to or lower than the set pressure when the load applied to the optional working device is larger than the set pressure, and controlling the electronically controlled hydraulic pump do.

At this time, it is preferable that the controller analyzes the electronic pressure command transmitted to the control device when the operation lever is operated, and controls the electronically controlled hydraulic pump by limiting the pressure to less than the set pressure.

In addition, the optional working device is preferably a bi-directional working device driven by a two-way flow of hydraulic fluid.

The apparatus may further include a relief setting step of setting the opening pressure of the relief valve connected to the option working device after the setting pressure applied to the optional working device is set to be higher than the set pressure in the setting pressure determination step.

The present invention as described above adjusts the electronically controlled hydraulic pump by restricting the pressure to less than the set pressure of the optional working device in accordance with the electronic pressure command transmitted from the control device. Therefore, it does not waste fuel in the engine.

Further, in the present invention, when the load applied to the optional working device is larger than the set pressure, the limit set below the set pressure is canceled and the maximum set pressure is supplied through the electronically controlled hydraulic pump. So that it can respond adaptively.

1 shows an excavator hydraulic system for a bidirectional option working apparatus according to the prior art.
Figure 2 shows an excavator hydraulic system for a bidirectional option working apparatus according to the present invention.
3 is a flowchart illustrating a method of controlling an optional work device of an excavator according to the present invention.
4 is a comparative diagram for explaining an effect of reducing the flow rate by the method of controlling an optional working device of an excavator according to the present invention.

Hereinafter, an optional control method of an excavator according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

Hereinafter, the optional working device of the front end of the excavator to which the present invention is applied will be described by taking as an example a two-way hydraulic fluid supply option working device such as a crusher and a shear.

However, it is apparent that the present invention is applicable to a one-way hydraulic fluid supply option working device such as a brakeer in addition to a two-way hydraulic fluid supply option working device.

First, before explaining an option control method for an excavator according to the present invention, an excavator hydraulic system driven by a bidirectional flow of hydraulic fluid such as a crusher or a shear described above will be described.

2, an excavator hydraulic system to which the present invention is applicable includes, for example, a lever pressure sensor 10, a control device 100, an electronically controlled hydraulic pump 30, a main control valve 40, a cylinder 50 for a working machine, And a relief valve portion (60).

Comparing the configurations of FIG. 2 with those of FIG. 1, the remaining configurations except for the controller 100 are the same or similar. It can be seen from the above that the object of the present invention is achieved only by the program change of the control apparatus 100 without changing the conventional configuration.

In the past, when the working load is exceeded, the residual operating fluid is recovered to the tank through the relief valve portion 60 so that the set pressure applied to the optional working device is maintained. Therefore, when the set pressure is maintained by using the relief valve portion 60, the engine torque increases and the fuel is wasted.

However, according to the present invention, the control device 100 electronically controls the pressure below the set pressure instead of using the relief valve portion 60 to maintain the maximum set pressure, so there is no waste of fuel.

That is, the present invention adjusts the electronically controlled hydraulic pump 30 through the improved control device 100, rather than the relief valve portion 60, by restricting the pressure to less than a set pressure according to the optional working device. Therefore, unnecessary additional operation of the engine does not waste fuel.

Further, when the load applied to the optional working device is larger than the set pressure, the limitation to the set pressure or less is canceled and the set pressure of the maximum size is supplied through the electronically controlled hydraulic pump 30, To be able to adaptively cope with the variation of

More specifically, the lever pressure sensor 10 senses the hydraulic pressure applied when operating the operation lever (not shown). The pressure of the operation lever sensed by the lever pressure sensor 10 is provided to the control device 100 and the control device 100 controls the electronically controlled hydraulic pump 30 by the electronic pressure command Provide an appropriate sized hydraulic pressure.

In the case of generating an electronic pressure command directly from the operation lever, the electronic pressure command can be transmitted to the control device 100 without the lever pressure sensor 10, and other parameters (e.g., current) can be used instead of the hydraulic pressure, And may transmit an electronic pressure command to the control device 100. [

The control device 100 controls the electronically controlled hydraulic pump 30 by limiting the pressure to a set pressure or less according to the type of the optional working device mounted as a main improvement part of the present invention. That is, the control unit 100 maintains the set pressure of the maximum size not the relief operation in the relief valve unit 60.

The control device 100 also controls the electronically controlled hydraulic pump 30 in an electronic manner in response to an electronic pressure command transmitted through the operation of an operation lever (e.g., a joystick or an optional operation switch).

On the other hand, when the load applied to the option working device is larger than the set pressure, the limit set below the set pressure is canceled. When the restriction is released, the maximum set pressure is supplied, which is minimal to cover the load and therefore can not be seen as fuel consumption.

Although not described above, the load applied to the optional working device may be measured by a pressure sensor (P) connected to the output of the electronically controlled hydraulic pump (30) or by monitoring the operating lever as is known or otherwise measured .

The electronically controlled hydraulic pump 30 supplies operating fluid stored in the oil tank T by an electronic pressure command of the control device 100 and operates by receiving power from the engine. Therefore, the unnecessary operation of the electronically controlled hydraulic pump 30 is reduced to improve fuel economy.

To this end, the electronic pressure command transmitted from the control apparatus 100 to the electronically controlled hydraulic pump 30 includes information of the operating pressure limited to a set pressure or less of the optional working apparatus, as described above. Of course, if the load is greater than the set pressure, release this restriction.

The electronically controlled hydraulic pump 30 includes a regulator 1 and a regulator 2 to which a pump 1 command and a pump 2 command are inputted from the controller 100 and a regulator 2 receives a swash plate tilting angle of the electronically controlled hydraulic pump 30, Respectively.

In addition, the swash plate angle of the electronically controlled hydraulic pump 30 is measured by the angle sensor and then provided to the control device 100, thereby enabling precise hydraulic control based on this.

The main control valve 40 supplies the hydraulic fluid provided by the electronically controlled hydraulic pump 30 to one end of the cylinder 50 for the working machine or the other end such as the post-cylinder head.

Two electronically controlled hydraulic pumps 30 are connected to one end and the other end of a cylinder 50 for a work machine via hydraulic lines, respectively. Accordingly, the working oil is supplied to the working machine cylinder 50, and the optional working device connected to the working machine cylinder 50 is operated as one end or the other end.

For example, when the optional working device is a bidirectional working oil supply system such as a crucher and a shear, if the working machine cylinder 50 is operated at one end, the crusher or shear is crushed and the working machine cylinder 50 When operated as the other end, the crusher or shear is opened.

The main control valve 40 is usually a solenoid valve or an electronic proportional pressure pedal (EPPR) valve.

The cylinder 50 for the working machine receives the operating fluid through the main control valve 40 and operates the cylinder rod inside the cylinder 50. The cylinder rod drives the optional working device attached to the front end of the excavator.

The relief valve unit 60 performs a relief operation when the working cylinder 50 is overloaded due to a combined operation or an unintended cause so that the operating oil is recovered to the tank. This will absorb the impact on the excavator and prevent equipment failure.

In the prior art, the maximum set pressure is maintained by the relief operation of the relief valve portion 60, but the relief valve portion 60 is not used in the present invention to maintain the set pressure.

The present invention limits the pressure in the control device (100) to a set pressure or lower and delivers an electronic pressure command. Therefore, the relief valve portion 60 performs the relief operation, meaning that the operating oil is recovered meaninglessly and does not waste fuel.

As described above, the relief valve unit 60 of the present invention is effective in protecting the equipment by performing a relief operation when the cylinder 50 for the working machine is overloaded due to a complex operation or unintended reasons.

Hereinafter, a method of controlling an optional working device of an excavator according to the present invention will be described as an example applied to an excavator hydraulic system having the configuration as shown in FIG.

As shown in FIG. 3, the method for controlling an optional working device of an excavator according to the present invention includes a set pressure determination step (S110), a pump control step (S121), and a restriction release step (S122). Further, if necessary, it further includes a relief setting step S110a.

In the setting pressure determining step (S110), when the optional working device is attached to the front end portion of the excavator, the pressure applied to the optional working device is set using the operating lever.

An optional working device is, for example, a two-way hydraulic supply option working device such as a crucher and a shear.

The set pressure is set according to the type of the optional working device based on various pressure specifications including the engine capacity of the excavator. The setting pressure according to the option working device depends on the type of excavator, but usually it is predetermined to 300bar or 320bar.

Therefore, when the operator views the instrument panel and selects a specific value corresponding to the corresponding option work device among the various option work devices, the set pressure is automatically set. Of course, you can also directly enter the set pressure value.

Next, the set pressure set according to the option working device is compared with the magnitude of the electronic pressure command transmitted to the electronically controlled hydraulic pump 30 by the operator through the operation lever (S120a). 3, P F is the pressure (i.e., the electronic pressure command) that is transmitted from the control device 100 to the electronically controlled hydraulic pump 30, and P TWS is the set pressure of the bidirectional option working device.

A pump control step S121 for controlling the electronically controlled hydraulic pump 30 so that the operating pressure limited to a set pressure or less is applied to the control device 100 corresponding to the magnitude of the electronic pressure command, .

On the other hand, when the magnitude of the electronic pressure command is larger than the set pressure and the load applied to the optional working device is larger than the set pressure, the control device 100 performs the restriction release step S122. That is, the restriction to control to operate below the set pressure is released.

As described above, according to the present invention, when the load applied to the optional working device is larger than the set pressure, it is possible to release the limitation to the set pressure or less and to supply the set pressure of the maximum size through the electronically controlled hydraulic pump 30, It can respond adaptively.

On the other hand, if necessary, after setting the set pressure applied to the optional working device in the set pressure determination step (S110), the relief setting for setting the opening pressure of the relief valve portion 60 connected to the optional working device higher than the set pressure Step S110a is performed.

The magnitude of the pressure set higher than the set pressure may vary from excavator to excavator, but is preferably set so that the relief operation of the relief valve portion 60 is performed when the pressure exceeds the set pressure by about 20 bar.

Accordingly, the relief valve unit 60 of the present invention protects the equipment (i.e., excavator) by performing a relief operation when the cylinder 50 for the working machine is overloaded due to a complex operation or an unintended cause.

As is known, the relief valve portion 60 includes an electron proportional control relief valve 61. Therefore, since the relief operation pressure can be electronically adjusted in the control device 100, the pressure of the entire relief valve portion 60 can be varied.

FIG. 4 shows the effect of reducing the flow rate by the method of controlling an optional working device of an excavator according to the present invention. 4 is according to the prior art, and FIG. 4 is according to the present invention.

As shown in the drawings, the present invention controls the electronically controlled hydraulic pump 30 so that the actual flow rate always reaches the predetermined flow rate.

As described above, since the flow rate supplied through the electronically controlled hydraulic pump 30 is reduced to an actual required amount, the engine torque can be lowered and the fuel consumption can be lowered.

The specific embodiments of the present invention have been described above. It is to be understood, however, that the scope and spirit of the present invention is not limited to these specific embodiments, and that various modifications and changes may be made without departing from the spirit of the present invention. If you have, you will understand.

Therefore, it should be understood that the above-described embodiments are provided so that those skilled in the art can fully understand the scope of the present invention. Therefore, it should be understood that the embodiments are to be considered in all respects as illustrative and not restrictive, The invention is only defined by the scope of the claims.

The present invention can be applied to a method of controlling an optional working device of an excavator in which an excavator option working device is controlled by using an electronically controlled control device instead of a relief valve but is limited to a set pressure or less of an optional working device .

10: Lever pressure sensor
30: Electronically controlled hydraulic pump
40: Main control valve
50: Cylinder for working machine
60: relief valve portion
61: Electronic proportional control relief valve
100: Control device

Claims (4)

A set pressure determining step (S110) of setting a pressure to be applied to the optional work device using an operation lever when the excavator is used with an optional work device attached thereto;
A pump control step (S121) of controlling the electronically controlled hydraulic pump (30) by limiting the maximum pressure command for the electronically controlled hydraulic pump (30) in the control device (100) to the set pressure or less; And
(S122) for controlling the electronically-controlled hydraulic pump (30) by releasing the restriction that the control device (100) is controlled to be lower than the set pressure when the load applied to the option working device is larger than the set pressure, And a controller for controlling the operation of the optional working device of the excavator.
The method according to claim 1,
Wherein the control device (100) analyzes the electronic pressure command transmitted to the control device (100) when the operation lever is operated and controls the electronically controlled hydraulic pump (30) by limiting the pressure to less than the set pressure Method of controlling an optional work device of an excavator. The method according to claim 1,
Wherein the optional work device is a bi-directional work device driven by a two-way flow of hydraulic fluid.
The method according to claim 1,
(S110a) for setting the opening pressure of the relief valve unit (60) connected to the option work unit to a value higher than the set pressure after setting the set pressure applied to the option working unit in the set pressure determination step (S110) Further comprising the steps of: controlling the operation of the optional working device of the excavator.
KR1020120151954A 2012-12-24 2012-12-24 Method for controlling the option actuator in excavator KR102008022B1 (en)

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Application Number Priority Date Filing Date Title
KR1020120151954A KR102008022B1 (en) 2012-12-24 2012-12-24 Method for controlling the option actuator in excavator

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Application Number Priority Date Filing Date Title
KR1020120151954A KR102008022B1 (en) 2012-12-24 2012-12-24 Method for controlling the option actuator in excavator

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KR20140083118A true KR20140083118A (en) 2014-07-04
KR102008022B1 KR102008022B1 (en) 2019-08-06

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107747331A (en) * 2017-05-03 2018-03-02 柳州柳工挖掘机有限公司 Crawler-mounted excavator auto-manual walking hydra-electric system

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0226303A (en) * 1988-07-12 1990-01-29 Kobe Steel Ltd Turning control circuit
JP2010059738A (en) * 2008-09-05 2010-03-18 Caterpillar Japan Ltd Hydraulic control circuit of working machine
WO2012121252A1 (en) * 2011-03-08 2012-09-13 住友建機株式会社 Shovel and method for controlling shovel

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0226303A (en) * 1988-07-12 1990-01-29 Kobe Steel Ltd Turning control circuit
JP2010059738A (en) * 2008-09-05 2010-03-18 Caterpillar Japan Ltd Hydraulic control circuit of working machine
WO2012121252A1 (en) * 2011-03-08 2012-09-13 住友建機株式会社 Shovel and method for controlling shovel

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107747331A (en) * 2017-05-03 2018-03-02 柳州柳工挖掘机有限公司 Crawler-mounted excavator auto-manual walking hydra-electric system

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