CN114439798A - Electro-hydraulic control system, electro-hydraulic control method and engineering machinery - Google Patents

Electro-hydraulic control system, electro-hydraulic control method and engineering machinery Download PDF

Info

Publication number
CN114439798A
CN114439798A CN202011199927.4A CN202011199927A CN114439798A CN 114439798 A CN114439798 A CN 114439798A CN 202011199927 A CN202011199927 A CN 202011199927A CN 114439798 A CN114439798 A CN 114439798A
Authority
CN
China
Prior art keywords
hydraulic lock
hydraulic
controller
main
electro
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202011199927.4A
Other languages
Chinese (zh)
Inventor
吕超
彭斌
肖飞
张小娜
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Caterpillar SARL
Original Assignee
Caterpillar SARL
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Caterpillar SARL filed Critical Caterpillar SARL
Priority to CN202011199927.4A priority Critical patent/CN114439798A/en
Publication of CN114439798A publication Critical patent/CN114439798A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • 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
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • 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
    • F15B20/00—Safety arrangements for fluid actuator systems; Applications of safety devices in fluid actuator systems; Emergency measures for fluid actuator systems
    • 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
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/02—Servomotor systems with programme control derived from a store or timing device; Control devices therefor
    • 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
    • F15B2211/80—Other types of control related to particular problems or conditions
    • F15B2211/86—Control during or prevention of abnormal conditions
    • F15B2211/8643—Control during or prevention of abnormal conditions the abnormal condition being a human failure

Abstract

The invention relates to an electro-hydraulic control system for a construction machine, comprising: a hydraulic lock master switch; the hydraulic lock relay is electrically connected with the hydraulic lock main switch; the hydraulic lock electromagnetic valve is electrically connected with the hydraulic lock relay; and a controller electrically connected to a main pump and a main valve of the construction machine so as to control actions of the main pump and the main valve, wherein the controller is configured to: detecting a closing signal of a main switch of the hydraulic lock; detecting an opening signal of a hydraulic lock relay; wherein when the controller does not detect the closing signal of the hydraulic lock main switch and detects the opening signal of the hydraulic lock relay, the controller sends electric signals to the main pump and the main valve so as to control the main pump and the main valve to be in the working state. The electro-hydraulic control system can avoid misoperation of an actuating mechanism caused by accidental touch or misoperation of an operating handle and the like, and eliminate potential safety hazards. The invention also relates to an electro-hydraulic control method for the engineering machinery and the engineering machinery comprising the electro-hydraulic control system.

Description

Electro-hydraulic control system, electro-hydraulic control method and engineering machinery
Technical Field
The invention relates to the field of electro-hydraulic control. In particular, the present invention relates to an electro-hydraulic control system and an electro-hydraulic control method for a construction machine. The invention also relates to engineering machinery comprising the electro-hydraulic control system.
Background
Work machines such as excavators, loaders, dozers, etc. are often equipped with electro-hydraulic control systems for providing hydraulic fluid (e.g., hydraulic oil) to hydraulic actuators such as swing motors, cylinders, etc. in response to an operator's operation to perform an action intended by the operator.
Fig. 1 schematically illustrates an electro-hydraulic control system commonly used in a prior art work machine, and fig. 3 schematically illustrates a hydraulic lock control method in the prior art electro-hydraulic control system.
As shown in fig. 3, the controller 4 is electrically connected to the on/off position of the hydraulic lock main switch 1 to detect an on signal of the hydraulic lock main switch 1 when the hydraulic lock main switch 1 is turned on. Referring to fig. 1, after the engine is started, an operator turns on a hydraulic lock main switch 1, a circuit is turned on, an electric signal turns on a hydraulic lock solenoid valve 3 through a hydraulic lock relay 2, and a controller 4 detects an on signal of the hydraulic lock main switch 1. Pilot oil from a pilot oil line (pilot pump or pressure reducing valve) can pass through the hydraulic lock solenoid valve 3 to the operating handle 6, thereby providing pilot hydraulic fluid required for the operation action. The controller 4 sends electric signals to main pump 13 of the construction machine and main valve control ports (electric control) 7 and 8 of main valve 11, so that the main pump 13 and the main valve 11 are in an operating state. At this time, when the operation handle 6 is operated, pilot oil is supplied to main valve control ports (pilot controls) 9 and 10 at both ends of the main valve 11, the main valve 11 is opened, and hydraulic oil from the main pump 13 is supplied to the hydraulic actuator 12, whereby the operation intended by the operator is completed.
The electro-hydraulic control system has certain defects in the aspect of safety.
On the one hand, when hydraulic lock relay 2 damages, open hydraulic lock master switch 1 back, the signal of telecommunication can't trigger hydraulic lock solenoid valve 3. And the controller 4 can judge that the machine works normally because the controller 4 detects the opening signal of the hydraulic lock main switch 1. However, the entire vehicle does not actually operate, and therefore cannot be reliably controlled.
On the other hand, when the hydraulic lock main switch 1 is disabled (at this time, the hydraulic lock main switch 1 is always in the off position) and the hydraulic lock relay 2 is functioning normally, if the current reaches the hydraulic lock relay 2 through some way, the electrical signal will turn on the hydraulic lock solenoid valve 3 through the relay 2. At this time, if the operation handle 6 or the like is touched accidentally or operated erroneously, the main valve 11 is reversed, and the actuators 12 (such as a rotary motor, an oil cylinder, or the like) are operated erroneously, thereby causing a safety hazard.
The present invention is directed to solving the above-mentioned problems of the prior art.
Disclosure of Invention
In order to overcome the defects in the prior art, the invention provides an electro-hydraulic control system and an electro-hydraulic control method for improving the whole vehicle operation safety of engineering machinery.
According to an aspect of the invention, an electro-hydraulic control system for a work machine is provided, comprising:
a hydraulic lock master switch;
the hydraulic lock relay is electrically connected with the hydraulic lock main switch;
the hydraulic lock electromagnetic valve is electrically connected with the hydraulic lock relay; and
a controller electrically connected to a main pump and a main valve of the construction machine to control operations of the main pump and the main valve,
wherein the controller is configured to:
detecting a closing signal of a main switch of the hydraulic lock;
detecting an opening signal of a hydraulic lock relay;
wherein when the controller does not detect the closing signal of the hydraulic lock main switch and detects the opening signal of the hydraulic lock relay, the controller sends electric signals to the main pump and the main valve so as to control the main pump and the main valve to be in the working state.
In the electro-hydraulic control system, the controller judges the logical relationship based on the closing/non-closing signal of the hydraulic lock main switch and the opening/closing signal of the hydraulic lock relay, and controls whether the main pump and the main valve need to be normally output according to the judgment result, so that the misoperation of an actuating mechanism caused by accidental touch or misoperation of an operating handle and the like is avoided, the potential safety hazard is eliminated, the safety control level is enhanced, and the control and safety requirements are realized at the minimum cost.
Advantageously, the controller is electrically connected to the closed position of the hydraulic lock master switch to detect the closed signal of the hydraulic lock master switch, and
the controller is electrically connected to a location downstream of the hydraulic lock relay and upstream of the hydraulic lock solenoid to detect an open signal of the hydraulic lock relay.
Advantageously, the controller is configured to control the main pump and the main valve to be in the inactive state when one of:
the controller detects the closing signal of the hydraulic lock master switch and does not detect the opening signal of the hydraulic lock relay;
the controller does not detect the closing signal of the hydraulic lock master switch and does not detect the opening signal of the hydraulic lock relay;
the controller detects the closing signal of the hydraulic lock master switch and detects the opening signal of the hydraulic lock relay.
Advantageously, when the hydraulic lock solenoid valve is energized, pilot hydraulic oil can be delivered to the operating handle.
According to another aspect of the invention, an electro-hydraulic control method for a work machine is disclosed, the work machine comprising:
a hydraulic lock master switch;
the hydraulic lock relay is electrically connected with the hydraulic lock main switch;
the hydraulic lock electromagnetic valve is electrically connected with the hydraulic lock relay; and
a controller electrically connected to a main pump and a main valve of the construction machine to control operations of the main pump and the main valve,
the electro-hydraulic control method is characterized by comprising the following steps:
detecting a closing signal of a main switch of the hydraulic lock through a controller;
detecting an opening signal of a hydraulic lock relay through a controller;
wherein when the controller does not detect a closing signal of the hydraulic lock main switch and detects an opening signal of the hydraulic lock relay, the controller sends electric signals to the main pump and the main valve so as to put the main pump and the main valve in an operating state.
Advantageously, the controller is electrically connected to the closed position of the hydraulic lock master switch to detect the closed signal of the hydraulic lock master switch, and
the controller is electrically connected to a location downstream of the hydraulic lock relay and upstream of the hydraulic lock solenoid to detect an open signal of the hydraulic lock relay.
Advantageously, the controller controls the main pump and the main valve to be in the inactive condition in one of:
the controller detects the closing signal of the hydraulic lock master switch and does not detect the opening signal of the hydraulic lock relay;
the controller does not detect the closing signal of the hydraulic lock master switch and does not detect the opening signal of the hydraulic lock relay;
the controller detects the closing signal of the hydraulic lock master switch and detects the opening signal of the hydraulic lock relay.
Advantageously, when the hydraulic lock solenoid is energized, pilot hydraulic oil is delivered to the operating handle.
According to another aspect of the invention, the invention relates to a working machine comprising an electro-hydraulic control system as described above.
Advantageously, the work machine is an excavator.
Drawings
Preferred embodiments of the present invention will be described in more detail below with reference to the schematic drawings. The drawings and the corresponding embodiments are for purposes of illustration only and are not intended to be limiting of the invention. In the drawings:
figure 1 schematically illustrates an electro-hydraulic control system commonly used in prior art work machines,
figure 2 schematically illustrates an electro-hydraulic control system for a work machine according to one embodiment of the invention,
FIG. 3 schematically illustrates a hydraulic lock control method in a prior art electro-hydraulic control system, and
fig. 4 schematically shows a hydraulic lock control method in the electro-hydraulic control system according to the present invention.
Detailed Description
Embodiments of the present invention are described below with reference to the drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of, and enabling description for, those skilled in the art. It will be apparent, however, to one skilled in the art that the present invention may be practiced without some of these specific details. Furthermore, it should be understood that the invention is not limited to the specific embodiments described. Rather, any combination of the features and elements described below is contemplated as carrying out the invention, whether or not they relate to different embodiments. Thus, the aspects, features, embodiments and advantages described below are for illustrative purposes only and should not be considered elements or limitations of the claims unless explicitly recited in a claim.
Fig. 4 schematically shows a hydraulic lock control method in the electro-hydraulic control system according to the present invention. As shown in fig. 4, on the one hand, the controller 4 is electrically connected to the off position of the hydraulic lock main switch 1 to detect the off signal of the hydraulic lock main switch 1, and on the other hand, the controller 4 is electrically connected to a position downstream of the hydraulic lock relay 2 and upstream of the hydraulic lock solenoid valve 3 to detect the on signal of the hydraulic lock relay 2.
When the hydraulic lock main switch 1 is not opened, the hydraulic lock main switch 1 is in a normally closed position. At this time, the controller 4 detects the off signal of the hydraulic lock main switch 1. Referring to fig. 2, when both the hydraulic lock main switch 1 and the hydraulic lock relay 2 are in normal functions, after the engine is started, when the hydraulic lock main switch 1 is opened by an operator, the circuit is connected, and the electric signal is connected to the hydraulic lock electromagnetic valve 3 through the hydraulic lock relay 2. At this time, the controller 4 does not detect the off signal of the hydraulic lock main switch 1 (in other words, the controller 4 determines that the hydraulic lock main switch 1 is in the on state), and the controller 4 detects the on signal of the hydraulic lock relay 2. The controller 4 sends electrical signals to main spool control ports (electrical control) 7, 8 of a main pump 13 and a main valve 11 of the construction machine so as to control the main pump 13 and the main valve 11 to be in an operating state. Pilot oil from a pilot oil passage (pilot pump or pressure reducing valve) is connected for providing pilot hydraulic fluid required for the operation action. At this time, when the operating handle 6 is operated, pilot oil is supplied to main spool control ports (pilot controls) 9 and 10 at both ends of the main valve 11, and the main valve 11 is opened to supply hydraulic oil from the main pump 13 to the hydraulic actuator 12.
According to the present invention, the controller 4 logically analyzes the electric signal (off or non-off signal) from the hydraulic lock master switch 1 and the electric signal (on or off signal) from the hydraulic lock relay 2, and the controller 4 sends electric signals to the main pump and the main valve to control the main pump and the main valve to be in an operating state only when the controller 4 does not detect the off signal of the hydraulic lock master switch 1 and detects the on signal of the hydraulic lock relay 2.
Table 1 shows that the controller 4 performs logical analysis based on the states of the hydraulic-lock main switch 1 and the hydraulic-lock relay 2 and controls the main pump and the main valve according to the determination result.
Hydraulic lock main switch Hydraulic lock relay Controller for controlling a motor Main pump and main valve
OFF OFF OFF OFF
ON OFF OFF OFF
OFF ON OFF OFF
ON ON ON ON
TABLE 1
As shown in table 1, when the controller 4 detects the OFF signal from the hydraulic lock main switch 1, the controller 4 determines that the hydraulic lock main switch 1 is in the OFF state (OFF). When the controller 4 does not detect the off signal from the hydraulic-lock main switch 1, the controller 4 determines that the hydraulic-lock main switch 1 is in the ON state (ON). When the controller 4 detects the ON signal of the hydraulic lock relay 2, it is determined that the hydraulic lock relay 2 is in the ON/off state (ON). When the controller 4 does not detect the on signal of the hydraulic lock relay 2, it is determined that the hydraulic lock relay 2 is in the OFF/disconnected state (OFF).
When any one of the hydraulic lock main switch 1 and the hydraulic lock relay 2 fails in function or fails simultaneously or feedback is in abnormal operation, the judgment result given by the controller 4 through logic analysis is OFF, namely the controller 4 judges that the machine is in a state of incapable of normal operation, the controller 4 informs the main pump 13 and the main valve 11 of the electric proportional pressure reducing valves 7 and 8 (electric control) controlling the reversing of the main valve cores to stop working, and the whole vehicle does not act. At this time, the main pump 13 and the main valve 11 are in a locked state, the main pump 13 is adjusted to a minimum output flow rate, and the main valve 11 does not respond to the pilot pressure and the control signal from the operation handle 6. Therefore, even if the operating handle 6 is operated by mistake or touched accidentally, no hydraulic oil enters the actuator, and malfunction does not occur.
Only when the controller 4 determines that the hydraulic lock main switch 1 is in the ON state (ON) and the hydraulic lock relay 2 is in the ON/ON state (ON), the controller 4 gives a determination result of ON by logic analysis indicating that the hydraulic lock main switch 1 and the hydraulic relay 2 function normally and the hydraulic lock main switch 1 is ON, and the controller 4 sends electric signals to the main pump 13 and the main valve 11 to control the main pump and the main valve to be in the operating state. Thereby enhancing the level of safety control of the control system.
In addition, if the controller 4 determines that the hydraulic lock main switch 1 is in the ON state (ON), but simultaneously determines that the hydraulic lock relay 2 is in the OFF/disconnected state (OFF), it indicates that the hydraulic lock relay 2 is malfunctioning.
The electro-hydraulic control system according to the present invention transmits a feedback signal to the controller 4 by electrically connecting the controller 4 with the closed position of the hydraulic lock main switch 1, and adds an electric wire between a position downstream of the hydraulic lock relay 2 and upstream of the hydraulic lock solenoid valve 3 and the controller 4 to transmit the feedback signal to the controller 4, and the controller 4 performs a logical relationship judgment based on the closed/non-closed signal of the hydraulic lock main switch 1 and the open/closed signal of the hydraulic lock relay 2, and controls whether the main pump 13 and the main valve 11 need to normally output according to the judgment result, thereby avoiding an erroneous operation, eliminating a potential safety hazard, enhancing a safety control level, and realizing control and safety requirements at a minimum cost. In addition, whether the hydraulic lock relay is damaged or not can be judged.
Industrial applicability
The electro-hydraulic control system according to the invention improves the safety of the engineering machinery through simple structural improvement, and realizes the control and safety requirements with minimum cost. This safety design logic is applicable to work machines such as excavators, loaders, and other types of machines with similar operating conditions.
After the engine is started, when the operator turns on the hydraulic lock master switch 1, the controller 4 controls the main pump 13 and the main valve 11 to be in the non-operating state at one of the following conditions:
the controller detects the closing signal of the hydraulic lock master switch and does not detect the opening signal of the hydraulic lock relay;
the controller does not detect the closing signal of the hydraulic lock master switch and does not detect the opening signal of the hydraulic lock relay;
the controller detects the closing signal of the hydraulic lock master switch and detects the opening signal of the hydraulic lock relay.
The controller 4 controls the main pump 13 and the main valve 11 to be in the operating state if and only if the controller 4 does not detect the off signal of the hydraulic lock master switch and detects the on signal of the hydraulic lock relay.
The electro-hydraulic control system and method of the present invention has been described above with reference to specific embodiments. It will be apparent to those skilled in the art that various modifications and variations can be made to the above disclosed embodiments without departing from the scope or spirit of the invention. For example, implementations of the invention may not include some of the specific features described, and the invention is not limited to the specific embodiments described, but rather contemplates any combination of the described features and elements. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the disclosed electro-hydraulic control system and method. It is intended that the specification and examples be considered as exemplary only, with a true scope being indicated by the following claims and their equivalents.

Claims (10)

1. An electro-hydraulic control system for a work machine, comprising:
a hydraulic lock master switch (1);
a hydraulic lock relay (2) electrically connected with the hydraulic lock main switch;
a hydraulic lock electromagnetic valve (3) electrically connected with the hydraulic lock relay; and
a controller (4) electrically connected to a main pump (13) and a main valve (11) of the construction machine to control operations of the main pump and the main valve,
wherein the controller is configured to:
detecting a closing signal of a main switch of the hydraulic lock;
detecting an opening signal of a hydraulic lock relay;
wherein when the controller does not detect the closing signal of the hydraulic lock master switch and detects the opening signal of the hydraulic lock relay, the controller sends electric signals to the main pump and the main valve so as to control the main pump and the main valve to be in an operating state.
2. The electro-hydraulic control system of claim 1,
the controller is electrically connected to the off position of the hydraulic lock main switch to detect an off signal of the hydraulic lock main switch, and
the controller is electrically connected to a location downstream of the hydraulic lock relay and upstream of the hydraulic lock solenoid valve to detect an open signal of the hydraulic lock relay.
3. The electro-hydraulic control system of claim 1 or 2, wherein the controller is configured to control the main pump and the main valve to be in the inactive state when one of:
the controller detects a closing signal of a main switch of the hydraulic lock and does not detect an opening signal of a relay of the hydraulic lock;
the controller does not detect a closing signal of a hydraulic lock main switch and does not detect an opening signal of a hydraulic lock relay;
the controller detects a closing signal of the hydraulic lock main switch and detects an opening signal of the hydraulic lock relay.
4. The electro-hydraulic control system of claim 1 or 2, wherein when the hydraulic lock solenoid valve is energized, pilot hydraulic oil can be delivered to the operating handle (6).
5. An electro-hydraulic control method for a work machine, the work machine comprising:
a hydraulic lock master switch (1);
a hydraulic lock relay (2) electrically connected with the hydraulic lock main switch;
a hydraulic lock electromagnetic valve (3) electrically connected with the hydraulic lock relay; and
a controller (4) electrically connected to a main pump (13) and a main valve (11) of the construction machine to control operations of the main pump and the main valve,
the electro-hydraulic control method is characterized by comprising the following steps:
detecting a closing signal of a main switch of the hydraulic lock through a controller;
detecting an opening signal of a hydraulic lock relay through a controller;
wherein when the controller does not detect a closing signal of the hydraulic lock main switch and detects an opening signal of the hydraulic lock relay, the controller sends electric signals to the main pump and the main valve so as to put the main pump and the main valve in an operating state.
6. The electro-hydraulic control method of claim 5,
the controller is electrically connected to the off position of the hydraulic lock main switch to detect an off signal of the hydraulic lock main switch, and
the controller is electrically connected to a location downstream of the hydraulic lock relay and upstream of the hydraulic lock solenoid to detect an open signal of the hydraulic lock relay.
7. The electro-hydraulic control method of claim 5 or 6, wherein the controller controls the main pump and the main valve to be in a non-operating state at one of:
the controller detects a closing signal of a main switch of the hydraulic lock and does not detect an opening signal of a relay of the hydraulic lock;
the controller does not detect a closing signal of a hydraulic lock main switch and does not detect an opening signal of a hydraulic lock relay;
the controller detects a closing signal of the hydraulic lock main switch and detects an opening signal of the hydraulic lock relay.
8. The electro-hydraulic control method according to claim 5 or 6, wherein when the hydraulic lock solenoid valve is energized, pilot hydraulic oil is delivered to the operating handle (6).
9. A work machine comprising an electro-hydraulic control system according to any of claims 1-4.
10. A working machine according to claim 9, wherein the working machine is an excavator.
CN202011199927.4A 2020-10-30 2020-10-30 Electro-hydraulic control system, electro-hydraulic control method and engineering machinery Pending CN114439798A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202011199927.4A CN114439798A (en) 2020-10-30 2020-10-30 Electro-hydraulic control system, electro-hydraulic control method and engineering machinery

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202011199927.4A CN114439798A (en) 2020-10-30 2020-10-30 Electro-hydraulic control system, electro-hydraulic control method and engineering machinery

Publications (1)

Publication Number Publication Date
CN114439798A true CN114439798A (en) 2022-05-06

Family

ID=81356953

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202011199927.4A Pending CN114439798A (en) 2020-10-30 2020-10-30 Electro-hydraulic control system, electro-hydraulic control method and engineering machinery

Country Status (1)

Country Link
CN (1) CN114439798A (en)

Similar Documents

Publication Publication Date Title
EP1790859B1 (en) Hydraulic controller for working machine
JP4232784B2 (en) Hydraulic control device for work machine
JP4928756B2 (en) Valve state detection module
CN109154153B (en) Safety system for construction machine
JP4453411B2 (en) Hydraulic control device for work machine
CN101228485A (en) Emergency shutdown system
EP3249117B1 (en) Control system for construction machine
JP7297596B2 (en) Hydraulic system for construction machinery
CA2031770C (en) Position-controlled proportional directional valve
JPH0719207A (en) Driving controller of hydraulic machinery
CN114439798A (en) Electro-hydraulic control system, electro-hydraulic control method and engineering machinery
CN107917114B (en) Method for detecting non-commanded spool positioning and preventing fluid flow to a hydraulic actuator
CN110226010B (en) Hydraulic control system for construction machine
EP2799692B1 (en) Engine control method of construction machine
US6764059B2 (en) Valve isolation system
EP0775836B1 (en) Apparatus for controlling selectively engageable detents in a pilot controller
JP4455959B2 (en) Hydraulic system
JPH0941427A (en) Hydraulic working machine
CN112064711A (en) Excavator remote control system, excavator remote control device and excavator
JP2926035B1 (en) Hydraulic control circuit of work machine
US11913480B2 (en) Integrated pressure diagnostic for off-highway steering isolation circuit
KR19980086021A (en) Malfunction prevention device of hydraulic construction machine
EP3707389B1 (en) Hydraulic circuit
JP3027529B2 (en) Interference prevention equipment for construction machinery, etc.
EP3821136B1 (en) Hydraulic machine comprising a hydraulic circuit

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination