CN113550372A - Automatic pressurization system and method for excavator - Google Patents

Automatic pressurization system and method for excavator Download PDF

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Publication number
CN113550372A
CN113550372A CN202110724680.1A CN202110724680A CN113550372A CN 113550372 A CN113550372 A CN 113550372A CN 202110724680 A CN202110724680 A CN 202110724680A CN 113550372 A CN113550372 A CN 113550372A
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China
Prior art keywords
valve
reversing valve
bucket
oil cylinder
sensor
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CN202110724680.1A
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CN113550372B (en
Inventor
宗波
尹超
崔广伟
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Xuzhou XCMG Excavator Machinery Co Ltd
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Xuzhou XCMG Excavator Machinery Co Ltd
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    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2264Arrangements or adaptations of elements for hydraulic drives
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/2025Particular purposes of control systems not otherwise provided for
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2264Arrangements or adaptations of elements for hydraulic drives
    • E02F9/2267Valves or distributors
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2278Hydraulic circuits
    • E02F9/2292Systems with two or more pumps
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02TCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00Road transport of goods or passengers
    • Y02T10/10Internal combustion engine [ICE] based vehicles
    • Y02T10/12Improving ICE efficiencies

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  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Operation Control Of Excavators (AREA)

Abstract

The invention discloses an automatic pressurization system of an excavator, which comprises a first main pump, a first reversing valve, a bucket rod oil cylinder, a four-way proportional valve, a bucket oil cylinder, a second reversing valve, a second main pump and a pilot pump, wherein the first main pump is connected with the first reversing valve; one input end of the reversing valve is connected with the output end of the first main pump, and the control end of the reversing valve is connected with a rod cavity and a rodless cavity of the bucket rod oil cylinder; a first sensor is arranged on an oil path between the first reversing valve and a rodless cavity of the bucket rod oil cylinder; the second input end of the reversing valve is connected with the output end of the second main pump, and the control end of the reversing valve is connected with a rod cavity and a rodless cavity of the bucket cylinder; a second sensor is arranged on an oil path between the second reversing valve and a rodless cavity of the bucket oil cylinder; the output end of the pilot pump is connected with the input end of the four-way proportional valve, and the control end of the four-way proportional valve is connected with the left position and the right position of the first reversing valve and the left position and the right position of the second reversing valve.

Description

Automatic pressurization system and method for excavator
Technical Field
The invention relates to an automatic supercharging system and method for an excavator, and belongs to the technical field of engineering machinery excavators.
Background
The prior hydraulic system of the excavator working device has the following problems: when the excavator excavates the operation, when meeting heavy objects such as stone, unable automatic ground instantaneous pressure boost matches the load in real time, acquires bigger digging force, causes driver's operation to experience relatively poorly.
During the excavation operation, the user discovers that excavation force is not enough, just can go to press the button of instantaneous pressure boost, and after the controller received this signal, just can rise the overflow pressure of main pump, and then promotes entire system's pressure, because of the human brain received signal, the process time spent of making corresponding reaction is long partially, leads to the whole time spent of instantaneous pressure boost to be long partially, has reduced excavation efficiency, has influenced driver's operation experience.
Disclosure of Invention
The invention aims to provide an automatic supercharging system of an excavator, which aims to overcome the defects that the whole time consumption is long due to instantaneous supercharging and the excavating efficiency is reduced in the prior art.
An automatic pressurization system of an excavator comprises a first main pump, a first reversing valve, a bucket rod oil cylinder, a four-way proportional valve, a bucket oil cylinder, a second reversing valve, a second main pump and a pilot pump;
one input end of the reversing valve is connected with the output end of the first main pump, and the control end of the reversing valve is connected with a rod cavity and a rodless cavity of the bucket rod oil cylinder; a first sensor is arranged on an oil path between the first reversing valve and a rodless cavity of the bucket rod oil cylinder;
the second input end of the reversing valve is connected with the output end of the second main pump, and the control end of the reversing valve is connected with a rod cavity and a rodless cavity of the bucket cylinder; a second sensor is arranged on an oil path between the second reversing valve and a rodless cavity of the bucket oil cylinder;
the output end of the pilot pump is connected with the input end of the four-way proportional valve, and the control end of the four-way proportional valve is connected with the left position and the right position of the first reversing valve and the left position and the right position of the second reversing valve.
Furthermore, the output end of the pilot pump is also connected with an electromagnetic valve, the control end of the electromagnetic valve is connected with a main overflow valve, and the two output ends of the main overflow valve are respectively connected to oil paths of the first main pump and the second main pump.
Furthermore, two output ends of the main overflow valve are provided with one-way valves.
Further, the four-way proportional valve comprises a solenoid valve A, a solenoid valve B, a solenoid valve C and a solenoid valve D; the electromagnetic valve A is connected with the left position of the second reversing valve, and the electromagnetic valve B is connected with the right position of the second reversing valve; the electromagnetic valve C is connected with the left position of the first reversing valve, and the electromagnetic valve D is connected with the right position of the first reversing valve.
An excavator automatic boosting method, executed by a controller, the method comprising:
acquiring the pressure of rodless cavities of a bucket rod oil cylinder and a bucket oil cylinder in real time through a sensor;
and the controller controls the electromagnetic valve to be electrified according to the preset pressure and the pressure collected by the first sensor and the second sensor, so that the main overflow valve pressurizes the rodless cavity.
Further, the method further comprises:
setting the pressure of the automatic pressurization to be P, the pressure of the first sensor to be P1, the pressure of the second sensor to be P2,
when P1 is more than or equal to P or P2 is more than or equal to P, P1 is more than or equal to mMPa, and P2 is more than or equal to mMPa; the electromagnetic valve is electrified and is delayed for T2 seconds, so that the set pressure of the main overflow valve is boosted to n times Pa.
Compared with the prior art, the invention has the following beneficial effects: the load can be intelligently matched by utilizing program setting, and if the load is greater than the set pressure, the function of instantaneous pressurization is automatically started, so that the aim of automatically improving the excavating force is fulfilled.
The program automatically completes the function of instantaneous pressurization, removes the time consumed by a user for judging that the excavating force is small and pressing an instantaneous increase button to increase the driving comfort and reduce the driving difficulty.
Under the condition that the parameters of the existing bucket oil cylinder and the bucket rod oil cylinder are not changed, the problem of automatically increasing excavating force is effectively solved, the excavating and loading speed is increased, and the user experience is improved.
Drawings
FIG. 1 is a drawing.
In the figure: 1. an electromagnetic valve; 2. a main overflow valve; 4. a first reversing valve; 5. a first sensor; 6. a bucket rod cylinder; 7. a quadruple proportional valve; 7-1, an electromagnetic valve A; 7-2 and an electromagnetic valve B; 7-3, an electromagnetic valve C; 7-4, an electromagnetic valve D; 8. a second sensor; 9. a bucket cylinder; 10. a second reversing valve; 11. a first main pump; 12. a second main pump; 13. a pilot pump.
Detailed Description
In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.
As shown in fig. 1, an automatic pressurization system of an excavator is disclosed, which comprises a first main pump 11, a first reversing valve 4, a boom cylinder 6, a quadruple proportional valve 7, a bucket cylinder 9, a second reversing valve 10, a second main pump 12 and a pilot pump 13;
the input end of the first reversing valve 4 is connected with the output end of the first main pump 11, and the control end of the first reversing valve is connected with a rod cavity and a rodless cavity of the bucket rod oil cylinder 6; a first sensor 5 is arranged on an oil path between the first reversing valve 4 and a rodless cavity of the bucket rod oil cylinder 6; the reversing valve 4: the left position controls the extension of a piston rod of the bucket rod oil cylinder, the middle position bucket rod oil cylinder keeps still, and the right position controls the retraction of the piston rod;
the input end of the second reversing valve 10 is connected with the output end of a second main pump 12, and the control end of the second reversing valve is connected with a rod cavity and a rodless cavity of the bucket cylinder 9; a second sensor 8 is arranged on an oil path between the second reversing valve 10 and a rodless cavity of the bucket oil cylinder 9; the reversing valve 10: the left position controls the extension of a piston rod of the bucket cylinder, the middle position bucket cylinder keeps still, and the right position controls the retraction of the piston rod of the bucket cylinder;
the output end of the pilot pump 13 is connected with the input end of the four-way proportional valve 7, and the control end of the four-way proportional valve 7 is connected with the left position and the right position of the reversing valve I4 and the left position and the right position of the reversing valve II 10;
the four-way proportional valve 7 comprises a solenoid valve A7-1, a solenoid valve B7-2, a solenoid valve C7-3 and a solenoid valve D7-4; the electromagnetic valve A7-1 is connected with the left position of the second reversing valve 10, and the electromagnetic valve B7-2 is connected with the right position of the second reversing valve 10; the electromagnetic valve C7-3 is connected with the left position of the reversing valve I4, and the electromagnetic valve D7-4 is connected with the right position of the reversing valve I4;
the electromagnetic valve A7-1 is electrified to control the extension of a piston rod of a bucket oil cylinder, and the bucket performs inward retraction;
the electromagnetic valve B7-2 is electrified to control the retraction of the piston rod of the bucket oil cylinder, so that the bucket performs outward swinging motion;
the electromagnetic valve C7-3 is electrified to control the extension of a piston rod of the bucket rod oil cylinder, and the bucket rod performs inward retraction;
the electromagnetic valve D7-4 is electrified to control the retraction of the piston rod of the bucket rod oil cylinder, and the bucket rod swings outwards;
when the electromagnetic valve 7-1 and the electromagnetic valve 7-3 are simultaneously electrified:
pressure oil output by the auxiliary pump is communicated to an XAk port of the reversing valve through an A1 port of the electromagnetic valve 7-1 and an oil pipe, a main valve core of the reversing valve 10 is pushed to move rightwards, the reversing valve 10 works in a left position state, at the moment, high-pressure oil output by the main pump flows to a rodless cavity of the bucket oil cylinder through the reversing valve 10, and a piston rod of the bucket oil cylinder is pushed to extend out, so that the bucket excavating action is realized;
the pressure oil output by the auxiliary pump is communicated with a XAa port of the reversing valve through an A3 port of the electromagnetic valve 7-3 and an oil pipe to push a main valve core of the reversing valve 4 to move rightwards, the reversing valve 4 works in a left position state, and at the moment, high-pressure oil output by the main pump flows to a large cavity of the bucket rod oil cylinder through the reversing valve 4 to push a piston rod of the bucket rod oil cylinder to extend out, so that the bucket rod excavating action is realized.
The output end of the pilot pump 13 is further connected with an electromagnetic valve 1, the control end of the electromagnetic valve 1 is connected with a main overflow valve 2, and the two output ends of the main overflow valve 2 are respectively connected to oil paths of the first main pump 11 and the second main pump 12.
Furthermore, two output ends of the main overflow valve 2 are provided with one-way valves.
An excavator automatic boosting method, executed by a controller, the method comprising:
acquiring the pressure of rodless cavities of a bucket rod oil cylinder and a bucket oil cylinder in real time through a sensor;
the controller controls the electromagnetic valve to be electrified according to preset pressure and pressure collected by the first sensor and the second sensor, so that the main overflow valve pressurizes the rodless cavity.
Further, the method further comprises:
setting the pressure of the automatic pressurization to be P, the pressure of the first sensor to be P1, the pressure of the second sensor to be P2,
when P1 is more than or equal to P or P2 is more than or equal to P, P1 is more than or equal to mMPa, and P2 is more than or equal to mMPa; the electromagnetic valve is electrified and is delayed for T2 seconds, so that the set pressure of the main overflow valve is boosted to n times Pa;
specifically, the set pressure (normal state) of the main relief valve 2 is Pa,
the pressure P1 of the sensor 5,
the pressure P2 of the sensor 8,
a set pressure P (recommended P is within 2MPa less than Pa, and the program can set a value) whether to automatically pressurize.
Pressurization conditions are as follows: the method comprises the following steps: p1 is more than or equal to P, P2 is more than or equal to P, P1 is more than or equal to 20MPa, and P2 is more than or equal to 20 MPa;
secondly, the step of: the time T1 seconds when the condition (r) is satisfied (the program may set a numerical value).
The control program executes: the electromagnetic valve 1 is electrified and delayed for T2 seconds (the program can set a value), so that the set pressure (pressurization) of the main overflow valve 2 is 1.1 times Pa, and the pressure is kept for a period of time T2.
And (3) supercharging result: larger digging force can be obtained within the time T2, the effect of improving the digging efficiency is achieved, and the digging experience of a user is improved.
In order to ensure the reliability of automatic pressurization of the main overflow valve 2 and prevent the system from entering a pressurization state again in a short time, after the primary pressurization is finished, an automatic pressurization program cannot be triggered again in a time interval T3; after the time interval T3 is exceeded, it is determined whether the supercharging condition is satisfied, and thus it is determined whether to enter the next automatic supercharging state according to the supercharging condition.
Specifically, when the electromagnetic valve 7-1 and the electromagnetic valve 7-3 are simultaneously electrified,
pressure oil output by the auxiliary pump is communicated to an XAk port of the reversing valve through an A1 port of the electromagnetic valve 7-1 and an oil pipe, a main valve core of the reversing valve 10 is pushed to move rightwards, the reversing valve 10 works in a left position state, at the moment, high-pressure oil output by the main pump flows to a rodless cavity of the bucket oil cylinder through the reversing valve 10, and a piston rod of the bucket oil cylinder is pushed to extend out, so that the bucket excavating action is realized;
the pressure oil output by the auxiliary pump is communicated with a XAa port of the reversing valve through an A3 port of the electromagnetic valve 7-3 and an oil pipe to push a main valve core of the reversing valve 4 to move rightwards, the reversing valve 4 works in a left position state, and at the moment, high-pressure oil output by the main pump flows to a large cavity of the bucket rod oil cylinder through the reversing valve 4 to push a piston rod of the bucket rod oil cylinder to extend out, so that the bucket rod excavating action is realized.
The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.

Claims (6)

1. An automatic pressurization system of an excavator is characterized by comprising a first main pump (11), a first reversing valve (4), a bucket rod oil cylinder (6), a four-way proportional valve (7), a bucket oil cylinder (9), a second reversing valve (10), a second main pump (12) and a pilot pump (13);
the input end of the first reversing valve (4) is connected with the output end of the first main pump (11), and the control end of the first reversing valve is connected with a rod cavity and a rodless cavity of the bucket rod oil cylinder (6); a first sensor (5) is arranged on an oil path between the first reversing valve (4) and a rodless cavity of the bucket rod oil cylinder (6);
the input end of the second reversing valve (10) is connected with the output end of the second main pump (12), and the control end of the second reversing valve is connected with a rod cavity and a rodless cavity of the bucket cylinder (9); a second sensor (8) is arranged on an oil path between the second reversing valve (10) and a rodless cavity of the bucket oil cylinder (9);
the output end of the pilot pump (13) is connected with the input end of the four-way proportional valve (7), and the control end of the four-way proportional valve (7) is connected with the left position and the right position of the reversing valve I (4) and the left position and the right position of the reversing valve II (10).
2. The automatic supercharging system of the excavator according to claim 1, wherein an electromagnetic valve (1) is further connected to the output end of the pilot pump (13), a main overflow valve (2) is connected to the control end of the electromagnetic valve (1), and two output ends of the main overflow valve (2) are respectively connected to oil paths of the first main pump (11) and the second main pump (12).
3. The automatic pressurization system of the excavator as claimed in claim 2, wherein two output ends of the main overflow valve (2) are provided with one-way valves.
4. The automatic supercharging system of the excavator according to claim 1, wherein the quadruple proportional valve (7) comprises a solenoid valve A (7-1), a solenoid valve B (7-2), a solenoid valve C (7-3) and a solenoid valve D (7-4); the electromagnetic valve A (7-1) is connected with the left position of the second reversing valve (10), and the electromagnetic valve B (7-2) is connected with the right position of the second reversing valve (10); the electromagnetic valve C (7-3) is connected with the left position of the first reversing valve (4), and the electromagnetic valve D (7-4) is connected with the right position of the first reversing valve (4).
5. An automatic boosting method of an excavator, which is executed by a controller, is characterized by comprising the following steps:
acquiring the pressure of rodless cavities of a bucket rod oil cylinder and a bucket oil cylinder in real time through a first sensor and a second sensor;
and the controller controls the electromagnetic valve to be electrified according to the preset pressure and the pressure collected by the first sensor and the second sensor, so that the main overflow valve pressurizes the rodless cavity.
6. The automatic pressurization method for the excavator according to claim 5, wherein the method further comprises:
setting the pressure of the automatic pressurization to be P, the pressure of the first sensor to be P1, the pressure of the second sensor to be P2,
when P1 is more than or equal to P or P2 is more than or equal to P, P1 is more than or equal to mMPa, and P2 is more than or equal to mMPa; the electromagnetic valve is electrified and is delayed for T2 seconds, so that the set pressure of the main overflow valve is boosted to n times Pa.
CN202110724680.1A 2021-06-29 2021-06-29 Automatic supercharging system and method for excavator Active CN113550372B (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115522594A (en) * 2022-08-26 2022-12-27 德州宝鼎液压机械有限公司 Automatic boosting device and automatic boosting method for excavator

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150033719A1 (en) * 2013-08-01 2015-02-05 Caterpillar Inc. Reducing Dig Force in Hydraulic Implements
CN104480991A (en) * 2014-12-16 2015-04-01 山河智能装备股份有限公司 Excavator hydraulic pump control loop and control method thereof
CN108729479A (en) * 2018-05-28 2018-11-02 柳州柳工挖掘机有限公司 Bucket rod cylinder of excavator hydraulic control system and control method
CN111442001A (en) * 2020-03-20 2020-07-24 宁波海天金属成型设备有限公司 Oil circuit structure for double closed-loop control of injection speed and injection force and control mode

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150033719A1 (en) * 2013-08-01 2015-02-05 Caterpillar Inc. Reducing Dig Force in Hydraulic Implements
CN104480991A (en) * 2014-12-16 2015-04-01 山河智能装备股份有限公司 Excavator hydraulic pump control loop and control method thereof
CN108729479A (en) * 2018-05-28 2018-11-02 柳州柳工挖掘机有限公司 Bucket rod cylinder of excavator hydraulic control system and control method
CN111442001A (en) * 2020-03-20 2020-07-24 宁波海天金属成型设备有限公司 Oil circuit structure for double closed-loop control of injection speed and injection force and control mode

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115522594A (en) * 2022-08-26 2022-12-27 德州宝鼎液压机械有限公司 Automatic boosting device and automatic boosting method for excavator

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