CN111622294A

CN111622294A - Excavator electro-hydraulic control system and method thereof

Info

Publication number: CN111622294A
Application number: CN202010640449.XA
Authority: CN
Inventors: 刘震; 苗国华; 刘淑强; ***; 刘巍; 冯立波; 任洪涛; 马瑞平
Original assignee: Shandong Lingong Construction Machinery Co Ltd
Current assignee: Shandong Lingong Construction Machinery Co Ltd
Priority date: 2020-07-06
Filing date: 2020-07-06
Publication date: 2020-09-04

Abstract

An excavator electro-hydraulic control system and a method thereof relate to the technical field of excavator control; the excavator electro-hydraulic control system and the method thereof comprise a variable driving device, an electro-hydraulic control device and an execution device; the electro-hydraulic control device comprises an oil return channel, at least one main pressure oil channel and a plurality of working oil port control units; the variable driving device is used for supplying liquid to the main pressure oil duct; an oil return control valve is arranged between the oil return channel and each main pressure oil channel; an oil inlet of the working oil port control unit is communicated with the main pressure oil duct, and the working oil port control unit is used for controlling the on-off of an oil path between the main pressure oil duct and the execution device and controlling the on-off of the oil path between the same load port of the execution device and the oil return channel. The invention aims to provide an excavator electro-hydraulic control system and an excavator electro-hydraulic control method, which aim to solve the technical problems of complex structure, high cost and poor universality of an excavator hydraulic control system in the prior art to a certain extent.

Description

Excavator electro-hydraulic control system and method thereof

Technical Field

The invention relates to the technical field of excavator control, in particular to an excavator electro-hydraulic control system and method.

Background

Excavators are important scrapers in construction machinery. A typical excavator hydraulic system includes a tank, a main pump, a main valve, an actuator, and other auxiliaries. The actuator includes, for example, a boom, a bucket, an arm, a travel motor, a swing motor, or the like.

The main control valve of the excavator is the most important part in an excavator hydraulic system, directly controls the flow distribution of the whole excavator, and influences the performance of the whole excavator such as controllability and oil consumption. However, the design and manufacture of conventional master control valves is limited by a number of factors. The main control valve body is generally cast, and because of the complex internal oil duct, the casting process is complex, the yield is low, the processing equipment is expensive, and the requirement on quality inspection personnel is higher; the main control valve assembly needs to integrate various flow control valves, and the structure is complex; the area characteristic of the main control valve rod is very difficult to adjust, different models need different area characteristics, even the models with the same tonnage, the area characteristic … … needs to be adjusted for various reasons due to different working devices, so that the main control valve is monopolized by several manufacturers in research and development, and the improvement and differentiation of the performance of the excavator are seriously hindered.

Therefore, due to the main control valve, the existing excavator hydraulic system has the problems of complex structure, high cost, poor universality and the like.

Disclosure of Invention

The invention aims to provide an excavator electro-hydraulic control system and an excavator electro-hydraulic control method, which aim to solve the technical problems of complex structure, high cost and poor universality of an excavator hydraulic control system in the prior art to a certain extent.

In order to achieve the purpose, the invention provides the following technical scheme:

an excavator electro-hydraulic control system comprises a variable driving device, an electro-hydraulic control device and an execution device;

the electro-hydraulic control device comprises an oil return channel, at least one main pressure oil channel and a plurality of working oil port control units;

the variable driving device is used for supplying liquid to the main pressure oil channel; an oil return control valve is arranged between the oil return channel and each main pressure oil channel;

the working oil port control unit comprises an oil inlet, an oil outlet and an oil return port; an oil inlet of the working oil port control unit is communicated with the main pressure oil duct, an oil outlet of the working oil port control unit is communicated with the execution device, and an oil return port of the working oil port control unit is communicated with the oil return channel; the working oil port control unit is used for controlling the on-off of an oil path between the main pressure oil duct and the execution device and controlling the on-off of the oil path between the same load port of the execution device and the oil return path.

In any of the above technical solutions, optionally, the executing device includes a first oil chamber and a second oil chamber;

the working oil port control unit communicated with the first oil cavity is a first working oil port control unit;

the working oil port control unit communicated with the second oil cavity is a second working oil port control unit;

the first working oil port control unit is used for controlling the on-off of an oil path between the main pressure oil duct and a first oil cavity of the execution device and controlling the on-off of the oil path between the first oil cavity of the execution device and the oil return channel;

the second working oil port control unit is used for controlling the connection and disconnection of an oil path from the main pressure oil duct to a second oil cavity of the execution device and controlling the connection and disconnection of the oil path between the second oil cavity of the execution device and the oil return channel;

when the execution device has a first action, the first working oil port control unit correspondingly controls the communication of an oil path between the main pressure oil duct and a first oil chamber of the execution device, and the second working oil port control unit correspondingly controls the communication of an oil path between a second oil chamber of the execution device and the oil return channel;

when the executing device has a second action, the second working oil port control unit correspondingly controls the communication of the oil path between the main pressure oil duct and the second oil chamber of the executing device, and the first working oil port control unit correspondingly controls the communication of the oil path between the first oil chamber of the executing device and the oil return channel.

In any of the above technical solutions, optionally, the excavator electro-hydraulic control system further includes an electronic controller and a pressure sensor electrically connected to the electronic controller;

the variable driving device, the executing device and the working oil port control unit are respectively electrically connected with the electronic controller;

the pressure sensor is arranged at the outlet of the variable driving device and used for collecting a pressure signal at the outlet of the variable driving device and transmitting the pressure signal to the electronic controller.

In any of the above technical solutions, optionally, the executing device includes one or more of a boom cylinder, an arm cylinder, a bucket cylinder, a swing motor, a left travel motor, and a right travel motor.

In any of the above technical solutions, optionally, the working oil port control unit includes a first working oil port control valve, a second working oil port control valve, and a working oil port check valve;

the oil inlet of the working oil port control unit, the working oil port check valve and the first working oil port control valve are sequentially communicated, and the working oil port check valve is used for preventing oil from flowing back to the oil inlet of the working oil port control unit from the first working oil port control valve;

and the second working oil port control valve is communicated between an oil outlet and an oil return port of the working oil port control unit.

In any of the above technical solutions, optionally, the first working oil port control valve and the second working oil port control valve respectively adopt a normally closed high-pressure large-flow proportional solenoid valve or a normally closed high-pressure large-flow valve composed of a proportional solenoid valve and a valve rod.

In any of the above technical solutions, optionally, an oil outlet of the working oil port control unit is connected to a load pressure sensor, and the load pressure sensor is configured to acquire a pressure signal of the execution device.

In any one of the above technical solutions, optionally, the number of the main pressure oil passages is multiple; the main pressure oil passages are communicated through one or more confluence control valves;

the confluence control valve adopts a normally closed high-pressure large-flow proportional solenoid valve or a normally closed high-pressure large-flow valve consisting of a proportional solenoid valve and a valve rod.

In any of the above technical solutions, optionally, the excavator electro-hydraulic control system includes an energy recovery device; the energy recovery device comprises an energy recovery one-way valve and an energy recovery control valve;

the energy recovery check valve is arranged between the execution device and the energy recovery control valve and used for preventing oil from flowing back to the execution device from the energy recovery control valve.

In any of the above technical solutions, optionally, the variable driving device is a variable displacement pump with adjustable displacement; the external input variable of the variable pump is an electric signal or a hydraulic signal; one or more outlets of the variable pumps are communicated with the main pressure oil channel;

and/or the oil return control valve adopts a normally open type proportional electromagnetic valve or a normally open valve consisting of a proportional electromagnetic valve and a slide valve.

An excavator electro-hydraulic control method is suitable for an excavator electro-hydraulic control system, and comprises the following steps:

when the electro-hydraulic control system of the excavator is in an ignition state, the electronic controller controls the oil return control valve so as to enable the main pressure oil passage and the oil return passage to be communicated through the oil return control valve; at the same time, the electronic controller controls the variable drive to minimize the displacement of the variable drive;

when an executing device of the electro-hydraulic control system of the excavator generates a first action, the electronic controller receives a first action signal generated by the executing device, controls the displacement of the variable driving device to increase, and controls the oil return control valve to reduce the oil return area from the main pressure oil passage to the oil return passage; the electronic controller controls the first working oil port control unit to control the communication of an oil path between the main pressure oil duct and a first oil chamber of the execution device, and controls the second working oil port control unit to correspondingly control the communication of an oil path between a second oil chamber of the execution device and the oil return duct;

when an executing device of the electro-hydraulic control system of the excavator generates a second action, the electronic controller receives a second action signal generated by the executing device, controls the displacement of the variable driving device to be increased, and controls the oil return control valve to reduce the oil return area from the main pressure oil passage to the oil return passage; the electronic controller controls the second working oil port control unit to control the communication of the oil path between the main pressure oil duct and the second oil chamber of the execution device, and controls the first working oil port control unit to correspondingly control the communication of the oil path between the first oil chamber of the execution device and the oil return channel.

The invention has the following beneficial effects:

the invention provides an excavator electrohydraulic control system and a method thereof.A variable driving device supplies liquid to a main pressure oil duct, an oil return control valve is arranged between an oil return channel and each main pressure oil duct, a working oil port control unit can control the on-off of an oil path between the main pressure oil duct and an execution device, and the working oil port control unit can also control the on-off of the oil path between the same load port of the execution device and the oil return channel; compared with the existing excavator hydraulic control system, the excavator electro-hydraulic control system is relatively simple in structure, low in cost, and greatly improved in universality and controllability, can realize accurate control, and saves energy.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a schematic diagram of a prior art excavator hydraulic system;

fig. 2 is a schematic diagram of a working oil port control unit and an execution device provided in the embodiment of the present invention;

fig. 3 is a characteristic diagram of a high-pressure large-flow normally closed proportional solenoid valve provided in an embodiment of the present invention;

FIG. 4 is a characteristic diagram of a high-pressure large-flow normally-open proportional solenoid valve provided in an embodiment of the present invention;

FIG. 5 is a schematic diagram of a main pressure oil passage of an electro-hydraulic control system of an excavator according to an embodiment of the invention;

FIG. 6 is a schematic view of the electronic controller shown in FIG. 5;

FIG. 7 is a schematic diagram of two main pressure oil passages of an electro-hydraulic control system of an excavator provided by the embodiment of the invention;

FIG. 8 is a schematic view of the electronic controller shown in FIG. 7;

FIG. 9 is a schematic diagram of a boom lowering potential energy return circuit according to an embodiment of the present invention;

fig. 10 is a schematic diagram of a slewing braking potential oil return circuit according to an embodiment of the present invention.

Icon: 1' -a master control valve; 2' -a boom cylinder; 3' -a bucket rod cylinder; 4' -a bucket cylinder; 5' -a rotary motor; 6' -left travel motor; 7' -right travel motor;

100-variable drive means; 200-an electro-hydraulic control device; 210-a main pressure gallery; 220-oil return channel; 230-a working oil port control unit; 231-an oil inlet of the working oil port control unit; 232-oil outlet of the working oil port control unit; 233-oil return port of working oil port control unit; 234-first working port control valve; 235-a second working oil port control valve; 236-working oil port check valve; 240-return oil control valve; 250-a confluence control valve;

300-an execution device; 310-boom cylinder; 320-a bucket rod oil cylinder; 330-a bucket cylinder; 340-a rotary motor; 350-left walking motor; 360-right travel motor; 370-spare oil port; 380-load pressure sensor; 400-an electronic controller; 410-a pressure sensor; 500-an energy recovery device; 510-energy recovery check valve; 520-energy recovery control valve.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or the orientations or positional relationships that the products of the present invention are conventionally placed in use, and are only used for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal", "vertical", "overhang" and the like do not imply that the components are required to be absolutely horizontal or overhang, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Some embodiments of the invention are described in detail below with reference to the accompanying drawings. The embodiments described below and the features of the embodiments can be combined with each other without conflict.

Examples

Referring to fig. 2 to 10, an electro-hydraulic control system of an excavator is provided in the present embodiment, and fig. 2 is a schematic diagram of a working oil port control unit and an execution device provided in the present embodiment; fig. 3 is a characteristic diagram of a high-pressure large-flow normally closed proportional solenoid valve provided in this embodiment, and fig. 4 is a characteristic diagram of a high-pressure large-flow normally open proportional solenoid valve provided in this embodiment; fig. 5 and 7 are schematic diagrams of an electro-hydraulic control system of an excavator provided by the embodiment, wherein one main pressure oil passage is shown in fig. 5 and is a single main pressure system, two main pressure oil passages are shown in fig. 7 and are multiple main pressure systems, fig. 6 is a schematic diagram of an electronic controller shown in fig. 5, and fig. 8 is a schematic diagram of an electronic controller shown in fig. 7; fig. 9 is a schematic diagram of a boom lowering potential oil return circuit according to the present embodiment; fig. 10 is a schematic diagram of a slewing braking potential oil return circuit provided in this embodiment.

The excavator electro-hydraulic control system provided by the embodiment is used for an excavator or similar machines.

Referring to fig. 2-10, the excavator electro-hydraulic control system comprises a variable drive device 100, an electro-hydraulic control device 200 and an actuating device 300.

The electro-hydraulic control apparatus 200 includes an oil return passage 220, at least one main pressure oil passage 210, and a plurality of working port control units 230.

The variable displacement drive 100 is used to supply liquid to the main pressure gallery 210; a return oil control valve 240 is provided between the return passage 220 and each of the main pressure oil passages 210.

The working oil port control unit 230 includes an oil inlet, an oil outlet, and an oil return port, as shown in fig. 2; an oil inlet 231 of the working oil port control unit is communicated with the main pressure oil passage 210, an oil outlet 232 of the working oil port control unit is communicated with the execution device 300, and an oil return port 233 of the working oil port control unit is communicated with the oil return passage 220; the working oil port control unit 230 is used for controlling the on-off of an oil path between the main pressure oil passage 210 and the execution device 300 and controlling the on-off of an oil path between the same load port of the execution device 300 and the oil return passage 220; that is, the same load port of the control actuator 300 can be communicated with the main pressure oil passage 210 and also can be communicated with the oil return passage 220.

Optionally, according to the configuration of the excavator electro-hydraulic control system, the requirement of the action time, the requirement of the flow output and the like, the excavator electro-hydraulic control system may be a single main pressure system or a multiple main pressure system according to the number of the main pressure oil passages 210 in the electro-hydraulic control device 200. In the single main pressure system, the electro-hydraulic control device 200 has a main pressure oil passage 210 therein, and the outlets of one or more variable driving devices 100 are connected to the main pressure oil passage 210, as shown in fig. 5; in the multi-line pressure system, two or more line pressure oil passages 210 are provided in the electro-hydraulic control device 200, and the outlets of one or more variable drive devices 100 are connected to these line pressure oil passages 210, and the number of the line pressure oil passages 210 shown in fig. 7 is two.

In the electro-hydraulic control system of the excavator in the embodiment, the variable driving device 100 supplies liquid to the main pressure oil channels 210, an oil return control valve 240 is arranged between each oil return channel 220 and each main pressure oil channel 210, the working oil port control unit 230 can control the on-off of the oil path between each main pressure oil channel 210 and the corresponding execution device 300, and the working oil port control unit 230 can also control the on-off of the oil path between the same load port of the corresponding execution device 300 and each oil return channel 220; compared with the existing excavator hydraulic control system, the excavator electro-hydraulic control system is relatively simple in structure, low in cost, and greatly improved in universality and controllability, can realize accurate control, and saves energy.

In the prior art, a control system of an excavator is mainly a hydraulic control system, and only a simple electric control system limits the power of a pump. Fig. 1 is a schematic diagram of a hydraulic system of a conventional excavator, in which the excavator controls a boom cylinder 2 ', an arm cylinder 3 ', a bucket cylinder 4 ', a swing motor 5 ', a left travel motor 6 ' and a right travel motor 7 ' through a main control valve 1 '. Hydraulic control systems have a number of disadvantages:

first, the hydraulic system is complex: mainly focusing on the main control valve. The main control valve distributes the flow of the pump, and various flow control valves are integrated on the main control valve. The hydraulic system is controlled by hydraulic signals in all logic, so the system is very complex.

Second, "special plane special type": basically, each machine type has a respective unique hydraulic system, and even if the tonnage is close, the adjustment of internal parts of the main control valve can reach the optimal state of the whole machine due to different working devices.

Thirdly, the cost is high: the hydraulic system is complex, and the main control valve has high manufacturing cost, so that the system cost is high. The cost of the hydraulic system of an individual machine type can account for more than one third of the cost of the whole machine.

Fourthly, automatic driving or remote control driving cannot be met: traditional hydraulic system can only be operated manually through the guide handle, can't satisfy remote control driving or autopilot.

Fifthly, the performance is not superior enough: because main hydraulic components such as pumps, valves and the like are monopolized by limited manufacturers in research, development, manufacturing and the like, and the whole machine factory is difficult to adjust main control valves and other key components which influence the whole machine performance according to the machine type, the whole machine performance cannot be optimized.

Sixth, once a problem is found, the difficulty of troubleshooting is large: the system is complex, the fault factors of the same fault phenomenon are various and the system is complex, so once problems occur, the difficulty of troubleshooting is high.

In recent years, with the development of electromagnetic valves, especially the gradual maturity of high-pressure large-flow proportional electromagnetic valves, it has become possible to break the bottleneck of development, production and manufacture of the traditional excavator main control valve. The whole excavator hydraulic system is revolutionarily improved, the proportion of electric control in the electro-hydraulic control is larger and larger, the whole system is greatly simplified, and the development of the electro-hydraulic control enables the engineering machinery field to be further driven to be unmanned. In the excavator electro-hydraulic control system in the embodiment, electro-hydraulic control is realized through the variable driving device 100, the electro-hydraulic control device 200 and the execution device 300, the structure of the control system is simplified, intelligent control of the control system can be improved, energy can be further saved, controllability is improved, and remote control or unmanned driving can be realized by matching with a related control strategy.

Referring to fig. 5 and 7, in an alternative of the present embodiment, the actuator 300 includes one or more of a boom cylinder 310, an arm cylinder 320, a bucket cylinder 330, a swing motor 340, a left travel motor 350, and a right travel motor 360. Alternatively, the actuator 300 includes a boom cylinder 310, an arm cylinder 320, a bucket cylinder 330, a swing motor 340, a left travel motor 350, and a right travel motor 360. Optionally, the electro-hydraulic control device 200 is provided with a spare oil port 370 for connecting the actuating device 300, so as to facilitate the later expansion of the electro-hydraulic control system of the excavator.

Referring to fig. 5 and 7, in an alternative of the present embodiment, the actuator 300 includes a first oil chamber and a second oil chamber; for example, the first oil chamber is a large chamber or a rodless chamber of the boom cylinder 310, the arm cylinder 320, or the bucket cylinder 330; the second oil chamber is a small chamber or a rod chamber of the boom cylinder 310, the arm cylinder 320, or the bucket cylinder 330. The first oil chamber and the second oil chamber may also be two working oil chambers of the swing motor 340, the left travel motor 350, or the right travel motor 360.

The working oil port control unit 230 communicated with the first oil chamber is a first working oil port control unit, that is, an oil outlet of the first working oil port control unit is communicated with the first oil chamber;

the working oil port control unit 230 communicated with the second oil chamber is the second working oil port control unit 230, that is, the oil outlet of the second working oil port control unit is communicated with the second oil chamber;

the first working oil port control unit is used for controlling the on-off of an oil path between the main pressure oil passage 210 and a first oil chamber of the execution device 300 and controlling the on-off of an oil path between the first oil chamber of the execution device 300 and the oil return passage 220;

the second working oil port control unit is used for controlling the on-off of an oil path from the main pressure oil passage 210 to a second oil chamber of the execution device 300 and controlling the on-off of an oil path between the second oil chamber of the execution device 300 and the oil return passage 220;

when the execution device 300 performs the first action, the first working oil port control unit correspondingly controls the communication of the oil path between the main pressure oil passage 210 and the first oil chamber of the execution device 300, and the second working oil port control unit 230 correspondingly controls the communication of the oil path between the second oil chamber of the execution device 300 and the oil return passage 220; at this time, the first working oil port control unit controls the disconnection of the oil path between the first oil chamber of the actuator 300 and the oil return passage 220, and the second working oil port control unit 230 controls the disconnection of the oil path between the main pressure oil passage 210 and the second oil chamber of the actuator 300.

When the second action of the execution device 300 occurs, the second working oil port control unit 230 correspondingly controls the communication of the oil path between the main pressure oil passage 210 and the second oil chamber of the execution device 300, and the first working oil port control unit correspondingly controls the communication of the oil path between the first oil chamber of the execution device 300 and the oil return passage 220; at this time, the second working port control unit 230 controls the disconnection of the oil path between the second oil chamber of the actuator 300 and the oil return passage 220, and the first working port control unit controls the disconnection of the oil path between the main pressure oil passage 210 and the first oil chamber of the actuator 300.

Alternatively, the first action of the actuator 300 may be, for example, a boom-up single action of the boom cylinder 310, and the second action of the actuator 300 may be, for example, a boom-down single action of the boom cylinder 310.

In an alternative aspect of this embodiment, the excavator electro-hydraulic control system includes an electronic controller 400 and a pressure sensor 410 electrically connected to the electronic controller 400.

The variable driving device 100, the execution device 300 and the working oil port control unit 230 are electrically connected with the electronic controller 400 respectively;

a pressure sensor 410 is provided at the outlet of the variable displacement drive 100, and the pressure sensor 410 is used for collecting a pressure signal at the outlet of the variable displacement drive 100 and transmitting the pressure signal to the electronic controller 400.

The electronic controller 400, also called electronic Control unit, ecu (electronic Control unit), and electronic Control unit, is composed of a microprocessor (CPU), a memory (ROM, RAM), an input/output interface (I/O), an analog-to-digital converter (a/D), and a large-scale integrated circuit such as a shaping circuit and a driving circuit.

Referring to fig. 2, in an alternative of the present embodiment, the working port control unit 230 includes a first working port control valve 234, a second working port control valve 235 and a working port check valve 236; it will be appreciated by those skilled in the art that the working port check valve 236 may also be a check valve assembly.

The oil inlet 231 of the working oil port control unit, the working oil port check valve 236 and the first working oil port control valve 234 are sequentially communicated, and the working oil port check valve 236 is used for preventing oil from flowing back from the first working oil port control valve 234 to the oil inlet 231 of the working oil port control unit, that is, the working oil port check valve 236 has a one-way flow limiting function of enabling the oil to flow from the main pressure oil passage 210 to the first working oil port control valve 234. The load pressure fluctuation of the actuator 300 is prevented from affecting the pressure of the main pressure oil passage 210 through the working port check valve 236, there is no one-way flow restriction between the actuator 300 and the oil return passage 220, and in some cases, when the system monitors that the actuator 300 generates negative pressure, the second working port control valve 235 may be opened to replenish oil to the actuator 300 through the oil return passage 220.

A second working oil port control valve 235 is communicated between the oil outlet 232 of the working oil port control unit and the oil return port 233 of the working oil port control unit.

Optionally, the oil outlet 232 of the working oil port control unit is connected with a load pressure sensor 380, and the load pressure sensor 380 is used for acquiring a pressure signal of the actuating device 300. Optionally, the load pressure sensor 380 is electrically connected to the electronic controller 400, and the load pressure sensor 380 transmits the collected pressure signal of the actuator 300 to the electronic controller 400.

Optionally, the outlet of the first working port control valve 234 is the inlet of the second working port control valve 235.

In an alternative of this embodiment, the first working oil port control valve 234 and the second working oil port control valve 235 are respectively a normally closed high-pressure large-flow proportional solenoid valve or a component having the same function and composed of a proportional solenoid valve and a valve rod, such as a normally closed high-pressure large-flow valve composed of a proportional solenoid valve and a valve rod. The working oil port control unit 230 can realize two-position two-way function through the two working oil port control valves, namely the first working oil port control valve 234 and the second working oil port control valve 235, and can realize the on-off from the oil inlet 231 of the working oil port control unit to the oil outlet 232 of the working oil port control unit. When the first working port control valve 234 is not energized, the oil inlet 231 of the working port control unit to the oil outlet 232 of the working port control unit are in a disconnected state. When the first working oil port control valve 234 is energized, the oil inlet 231 of the working oil port control unit is communicated with the oil outlet 232 of the working oil port control unit through the first working oil port check valve 236, and the communication area between the oil inlet 231 of the working oil port control unit and the oil outlet 232 of the working oil port control unit, or when the pressure of the oil inlet 231 of the working oil port control unit and the pressure of the oil outlet 232 of the working oil port control unit are fixed, the through-flow from the oil inlet 231 of the working oil port control unit to the oil outlet 232 of the working oil port control unit have a fixed controllable geometric relationship with the energized current, and the larger the current is, the larger the through-flow area is, and the maximum geometric value is reached. As shown in fig. 3, the correlation curve is a flow rate versus current curve under the differential pressure Δ P ═ C (C is a constant).

In this embodiment, the electronic controller 400 is configured to analyze and process various signals and send instructions to the first working port control valve 234 and the second working port control valve 235 in the electro-hydraulic control system. The relevant input and output signals of the electronic controller 400 are shown in table 1:

TABLE 1

Referring to fig. 7, in an alternative of the present embodiment, the number of the main pressure oil passage 210 is plural; the plurality of main pressure oil passages 210 communicate with each other through one or more confluence control valves 250; the merge control valve 250 is used to connect the main pressure oil passages 210, and when the operation time and flow rate requirements require, the merge control valve 250 is energized to merge the multiple pump flow rates inside the electro-hydraulic control device 200. In fig. 6, taking a double main pressure oil passage as an example, the two main pressure oil passages 210 may communicate through a confluence control valve 250.

Alternatively, the merge control valve 250 may be a normally closed high-pressure large-flow proportional solenoid valve or a component having the same function and composed of a proportional solenoid valve and a valve rod, such as a normally closed high-pressure large-flow valve composed of a proportional solenoid valve and a valve rod.

Referring to fig. 9 and 10, in an alternative of the present embodiment, an excavator electro-hydraulic control system includes an energy recovery device 500; the energy recovery device 500 includes an energy recovery check valve 510 and an energy recovery control valve 520;

an energy recovery check valve 510 is disposed between the actuator 300 and the energy recovery control valve 520, and the energy recovery check valve 510 is used for preventing the oil from flowing back to the actuator 300 from the energy recovery control valve 520. The energy recovery check valve 510 is used for realizing the one-way flow from the working port control unit 230 to the energy recovery control valve 520, and the energy recovery control valve 520 and the second working port control valve 235 for controlling the oil return of the working ports act together to recover energy.

For example, referring to fig. 9, an energy recovery device 500 is added to a large-chamber oil path of the boom cylinder 310, the energy recovery device 500 includes an energy recovery check valve 510 and an energy recovery control valve 520, and the energy recovery control valve 520 is a two-position two-way valve whose electric signal is controllable. The energy recovery check valve 510 is used for realizing the one-way flow from the boom cylinder large cavity to the energy recovery control valve 520, and the energy recovery control valve 520 and the second working port control valve 235 for controlling the return oil of the working ports act together to control the boom descending speed and recover the potential energy when the boom descends. The recovered pressure oil is led to an energy recovery and reutilization oil passage.

For another example, referring to fig. 10, an energy recovery device 500 is added to the oil path of the working oil port of the rotary motor 340, the energy recovery device 500 includes an energy recovery check valve 510 and an energy recovery control valve 520, and the energy recovery control valve 520 is a two-position two-way valve with controllable electric signals. The energy recovery check valve 510 is used for realizing the one-way flow from the working oil port of the rotary motor 340 to the energy recovery control valve 520, and the energy recovery control valve 520 and the second working oil port control valve 235 for controlling the oil return of the working oil port act together to control the rotary speed and recover the potential energy during the rotary braking. The pressure oil at the time of the swing braking may be recycled to the main pressure oil passage 210, or used in another function. The recovered pressure oil is led to an energy recovery and reutilization oil passage.

Referring to fig. 2-10, in an alternative to the present embodiment, the variable displacement drive 100 is a variable displacement pump with adjustable displacement; the external input variable of the variable pump is an electric signal or a hydraulic signal for adjusting the displacement of the pump; in the whole working process of the excavator, the displacement of the pump is continuously adjusted according to the characteristics of the pump and the direct or indirect control of the electronic controller 400, so that the flow demand of the whole excavator electro-hydraulic control system is met, and the energy-saving purpose is achieved. The outlets of the one or more variable displacement pumps are in communication with the main pressure gallery 210; that is, the outlet of one or more variable displacement pumps is in communication with each of the main pressure oil passages 210. For example, the electro-hydraulic control device 200 has two or more main pressure oil passages 210 therein, and the outlets of one or more variable pumps are connected to the main pressure oil passages 210; a normally open type return flow control valve is connected in series between each main pressure oil passage 210 and the return passage 220.

In the alternative of this embodiment, the oil return control valve 240 adopts a normally open type proportional solenoid valve or a component having the same function composed of a proportional solenoid valve and a spool valve, such as a normally open valve composed of a proportional solenoid valve and a spool valve. When the return control valve 240 is not energized, the main pressure gallery 210 and the return gallery 220 are directly connected through the return control valve 240. The oil return control valve 240 can control the oil return area from the main pressure oil passage 210 to the oil return passage 220, and when the oil pressure in the main pressure oil passage 210 and the oil pressure in the oil return passage 220 are fixed, the through flow rate from the main pressure oil passage 210 to the oil return passage 220 has a fixed controllable geometric relationship with the current flowing through, and the larger the current is, the smaller the through flow area is until the geometric minimum value is reached. As shown in fig. 5, in the single-main pressure system, the main pressure oil passage 210 of the electro-hydraulic control device 200 is connected to the oil return passage 220 through a normally open type oil return control valve 240 (the oil return control valve has a code number S29); in the multi-main pressure system, a normally open type oil return control valve 240 is connected in series between each pressure oil passage and the oil return passage 220 in the electro-hydraulic control device 200, fig. 7 shows the multi-main pressure system with two main pressure oil passages 210, and two oil return control valves S29 and S30(S29 is the code of one of the oil return control valves, and S30 is the code of the other oil return control valve) are connected in series between the two main pressure oil passages 210 and the oil return passage, respectively. The oil inlet and the oil outlet of the normally open type oil return control valve 240 meet the following requirements: when the oil return control valve 240 is not electrified, the oil inlet and the oil outlet of the oil return control valve 240 are in a communicated and unthrottled state; after the oil return control valve 240 is powered on, the oil inlet and the oil outlet of the oil return control valve are in a throttling or disconnecting state, and the connection area between the oil inlet and the oil outlet of the oil return control valve 240, or when the pressure of the oil inlet and the pressure of the oil outlet are fixed, the through flow from the oil inlet to the oil outlet of the oil return control valve 240 have a fixed controllable geometric relationship with the current, and the larger the current is, the smaller the through flow area is until the geometric minimum value is reached. As shown in fig. 4, the correlation curve is a flow rate versus current curve under the differential pressure Δ P ═ C (C is a constant).

The embodiment also provides an excavator electro-hydraulic control method, which is suitable for the excavator electro-hydraulic control system, and the method comprises the following steps:

when the electro-hydraulic control system of the excavator is in an ignition state, the electronic controller 400 controls the oil return control valve 240 so that the main pressure oil passage 210 is communicated with the oil return passage 220 through the oil return control valve 240; meanwhile, the electronic controller 400 controls the variable-displacement drive device 100 to minimize the displacement of the variable-displacement drive device 100; for example, referring to fig. 5 and 6, the Sc29 signal port in the electronic controller 400 outputs a signal to control the oil return control valve S29, the input current of the oil return control valve S29 is i' 0, at this time, the main pressure oil passage 210 and the oil return passage 220 are connected through the oil return control valve S29, the flow area of the input/output port of the oil return control valve S29 is large, and the pressure loss is small; at the same time, the Sc31 signal port in the electronic controller 400 outputs a signal that acts directly or indirectly on the signal port of the variable drive 100 (which has the designation cpi1) to minimize the displacement of the variable drive 100. At the moment, the pump port displacement is small, the pressure loss of the whole hydraulic system is small, the energy consumption loss is small, and the energy-saving purpose is achieved. Referring to fig. 7 and 8, for the multi-pressure system, the Sc29 signal port and the Sc30 signal port in the electronic controller 400 output signals to control the oil return control valves S29 and S30, the input currents of the oil return control valves S29 and S30 are i' 0, at this time, the first main pressure oil passage is connected with the oil return passage 220 through the oil return control valve S29, the first main pressure oil passage 210 is connected with the oil return passage 220 through the oil return control valve S30, and the flow areas of the input and output ports of the oil return control valves S29 and S30 are large and the pressure loss is small; meanwhile, the Sc31 signal port and the Sc32 signal port in the electronic controller 400 output signals which directly or indirectly act on the cpi1 and cpi2 signal ports of the variable-displacement drive device 100 to minimize the displacement. At the moment, the pump port displacement is small, the pressure loss of the whole hydraulic system is small, the energy consumption loss is small, and the energy-saving purpose is achieved.

Optionally, when the actuator 300 of the electro-hydraulic control system of the excavator generates the first action, the electronic controller 400 receives a signal that the actuator 300 generates the first action and controls the variable drive device 100 to increase the displacement, and controls the return control valve 240 to reduce the return area from the main pressure oil passage 210 to the return passage 220; the electronic controller 400 controls the first working oil port control unit to control the communication of the oil path between the main pressure oil passage 210 and the first oil chamber of the execution device 300, and controls the second working oil port control unit 230 to correspondingly control the communication of the oil path between the second oil chamber of the execution device 300 and the oil return passage 220; at this time, the first working oil port control unit controls the disconnection of the oil path between the first oil chamber of the actuator 300 and the oil return passage 220, and the second working oil port control unit 230 controls the disconnection of the oil path between the main pressure oil passage 210 and the second oil chamber of the actuator 300.

Alternatively, when the actuator 300 of the electro-hydraulic control system of the excavator generates the second action, the electronic controller 400 receives a signal that the actuator 300 generates the second action and controls the variable displacement driving device 100 to increase the displacement, and controls the oil return control valve 240 to reduce the oil return area from the main pressure oil passage 210 to the oil return passage 220; the electronic controller 400 controls the second working port control unit 230 to control the communication of the oil path between the main pressure oil passage 210 and the second oil chamber of the actuator 300, and controls the first working port control unit to correspondingly control the communication of the oil path between the first oil chamber of the actuator 300 and the oil return passage 220. At this time, the second working port control unit 230 controls the disconnection of the oil path between the second oil chamber of the actuator 300 and the oil return passage 220, and the first working port control unit controls the disconnection of the oil path between the main pressure oil passage 210 and the first oil chamber of the actuator 300.

In order to more clearly illustrate the technical solution of the present embodiment, referring to the multi-pressure control unit shown in fig. 7 and 8, two main pressure oil passages are taken as an example for description, in the present application, the related drawings only show some embodiments of the present embodiment, and therefore, should not be taken as a limitation to the protection scope of the present embodiment.

After the power of the whole excavator electro-hydraulic control system is switched on, when the excavator electro-hydraulic control system does not act, the codes of the first working oil port control valves 234 and the second working oil port control valves 235 of the plurality of working oil port control units 230 are working oil port control valves S1 to S28, and the input currents of the working oil port control valves S1 to S28 are at i0 shown in fig. 3; the normally open return control valve 240 between the main pressure gallery 210 and the return gallery 220 has an input current at i' 0 shown in fig. 4.

Tables 2 and 3 are diagrams of the solenoid valve energization matrix in the electro-hydraulic control apparatus 200.

TABLE 2

TABLE 3

The following are exemplified:

boom cylinder 310 actuates boom-up single action:

the CBU signal port in the electronic controller 400 receives a complete machine boom-up action signal of the excavator electro-hydraulic control system, and the signal may be a remote control signal or an electrical signal converted from other devices, such as an electronic control handle.

For a single-pressure system, the electronic controller 400 processes the signal received by the CBU signal port, and adjusts the output signal of the Sc31 signal port according to the value of the signal, so that the displacement of the variable displacement drive 100 is increased; meanwhile, the output signal size of the Sc29 signal port is adjusted according to the signal value of the CBU signal port; the current of the Sc29 signal port is increased to reach the i '1 position or directly reach the position greater than or equal to i' 3, and at the moment, the pressure is quickly built in the main pressure oil passage 210; meanwhile, the current of the Sc2 signal port is adjusted, and after the current of the Sc2 signal port reaches a certain value (greater than or equal to i1), an oil inlet way of a large cavity of the movable arm oil cylinder is opened; meanwhile, the current of Sc3 is adjusted, and after the current of Sc3 reaches a certain value (greater than or equal to i1), an oil return path of a small cavity of the movable arm oil cylinder is opened; in this way, the boom raising operation is realized. When the boom raising operation signal requires that the boom raising operation is slow, as shown in fig. 3, the flow rate of the pressure oil to the boom large chamber is small at i2 as the input current of S2, and the boom is raised slowly; when the boom raising operation signal requires an increase in the boom raising operation, as shown in fig. 3, the flow rate of the pressure oil to the boom large chamber becomes large at i3 as the input current of S2, and the boom raising speed increases; when the boom is required to ascend at the fastest speed, as shown in fig. 3, the input current of S2 is at imax, the flow rate of the pressure oil to the boom large cavity is the largest, and the boom ascending speed is the fastest. When the movable arm ascends, the oil return amount of the small cavity of the movable arm is adjusted according to different types, different working conditions and the like, and the purpose of different oil return areas is achieved, so that the action performance of the movable arm is optimal.

For a multi-pressure system, the electronic controller 400 processes signals received by the CBU signal ports, and adjusts output signals of the Sc31 signal port and the Sc32 signal port according to the value of the signals, so that the displacement of the variable drive device 100 is increased; meanwhile, the output signal size of the Sc29 signal port is adjusted according to the signal value of the CBU signal port; the current of the Sc29 signal port is increased to reach the position i '1 or directly reach the position more than or equal to i' 3, and at the moment, the pressure is quickly built in the second main pressure oil channel; meanwhile, the current of the Sc2 signal port is adjusted, and after the current of the Sc2 signal port reaches a certain value (greater than or equal to i1), an oil inlet way of a large cavity of the movable arm oil cylinder is opened; meanwhile, the current of the Sc3 signal port is adjusted, and after the current of the Sc3 signal port reaches a certain value (greater than or equal to i1), an oil return path of a small cavity of the movable arm oil cylinder is opened; in this way, the boom raising operation is realized. Particularly, a high-pressure large-flow normally-closed proportional solenoid valve is arranged between the first main pressure oil passage and the second main pressure oil passage, when the first main pressure oil passage and the second main pressure oil passage need to be communicated due to factors such as overall system parameters, action time requirements and the like, the oil return control valve S30 is powered on, the first main pressure oil passage quickly builds pressure, meanwhile, the Sc0 signal port is powered on, the confluence control valve S0 is opened, the first main pressure oil passage and the second main pressure oil passage are converged, and the discharge volumes of the two pumps are simultaneously supplied to the boom cylinder. When the boom raising operation signal requires that the boom raising operation is slow, as shown in fig. 3, the flow rate of the pressure oil to the boom large chamber is small at i2 as the input current of S2, and the boom is raised slowly; when the boom raising operation signal requires an increase in the boom raising operation, as shown in fig. 3, the flow rate of the pressure oil to the boom large chamber becomes large at i3 as the input current of S2, and the boom raising speed increases; when the boom is required to ascend at the fastest speed, as shown in fig. 3, the input current of S2 is at imax, the flow rate of the pressure oil to the boom large cavity is the largest, and the boom ascending speed is the fastest. When the movable arm ascends, the oil return amount of the small cavity of the movable arm is adjusted according to different types, different working conditions and the like, and the purpose of different oil return areas is achieved, so that the action performance of the movable arm is optimal.

Boom cylinder 310 actuates boom down single action:

for a single pressure system, the CBD signal port in the electronic controller 400 receives a signal of the boom lowering action of the whole machine, and the signal may be a remote control signal or an electrical signal converted from other devices, such as an electronic control handle. The electronic controller 400 processes the signal received by the CBD signal port, and adjusts the output signal of the Sc31 signal port according to the value of the signal, so that the displacement of the variable driving device 100 is increased; meanwhile, the output signal size of the Sc29 signal port is adjusted according to the signal value of the CBD signal port; the current of the Sc29 signal port is increased to reach the i '1 position or directly reach the position greater than or equal to i' 3, and at the moment, the pressure is quickly built in the main pressure oil passage 210; meanwhile, the current of the Sc4 signal port is adjusted, and after the current of the Sc4 signal port reaches a certain value (greater than or equal to i1), an oil inlet way of a small cavity of the movable arm oil cylinder is opened; meanwhile, the current of the Sc1 signal port is adjusted, and after the current of the Sc1 signal port reaches a certain value (greater than or equal to i1), an oil return path of a large cavity of the movable arm oil cylinder is opened; in this way, the boom lowering operation is realized. When the boom lowering operation signal requires that the boom lowering operation is slow, as shown in fig. 3, the input current of S4 is i2, the flow rate of the pressure oil to the boom small chamber is small, and the boom is lowered slowly; when the boom lowering operation signal requires an increase in the boom lowering operation, as shown in fig. 3, the flow rate of the pressure oil to the boom small chamber becomes large at i3 as the input current of S4, and the boom lowering speed increases; when the boom is required to descend at the fastest speed, as shown in fig. 3, the input current of S2 is at imax, the flow rate of the pressure oil to the boom small cavity is the largest, and the boom descending speed is the fastest. When the movable arm descends, the oil return amount of the large cavity of the movable arm is adjusted according to different types, different working conditions, different descending speed requirements and the like, the Sc1 current is adjusted, the purpose of different oil return areas is achieved, and therefore the action performance of the movable arm is optimal.

For a multi-pressure system, the electronic controller 400 processes the signal received by the CBD, and adjusts the Sc31 signal port and the Sc32 output signal according to the magnitude of the signal value, so that the displacement of the variable displacement drive 100 is increased; meanwhile, the output signal size of the Sc29 signal port is adjusted according to the value of the CBD signal; the current of the Sc29 signal port is increased to reach the position i '1 or directly reach the position more than or equal to i' 3, and at the moment, the pressure is quickly built in the second main pressure oil channel; meanwhile, the current of Sc4 is adjusted, and after the current of Sc4 reaches a certain value (greater than or equal to i1), an oil inlet passage of a small cavity of the movable arm oil cylinder is opened; meanwhile, the current of Sc1 is adjusted, and after the current of Sc1 reaches a certain value (greater than or equal to i1), an oil return path of a large cavity of the boom oil cylinder is opened; in this way, the boom lowering operation is realized. Particularly, a high-pressure large-flow normally-closed proportional solenoid valve is arranged between the first main pressure oil passage and the second main pressure oil passage, when the two pressure oil passages, namely the first main pressure oil passage and the second main pressure oil passage, need to be communicated due to factors such as overall system parameters and action time requirements, the oil return control valve S30 is electrified, the first main pressure oil passage quickly builds pressure, meanwhile, Sc0 is electrified, the confluence control valve S0 is opened, the first main pressure oil passage and the second main pressure oil passage are converged, and the discharge volumes of the two pumps are simultaneously supplied to the boom cylinder. When the boom lowering operation signal requires that the boom lowering operation is slow, as shown in fig. 3, the input current of S4 is i2, the flow rate of the pressure oil to the boom small chamber is small, and the boom is lowered slowly; when the boom lowering operation signal requires an increase in the boom lowering operation, as shown in fig. 3, the flow rate of the pressure oil to the boom small chamber becomes large at i3 as the input current of S2, and the boom lowering speed increases; when the boom is required to descend at the fastest speed, as shown in fig. 3, the input current of S4 is at imax, the flow rate of the pressure oil to the boom small cavity is the largest, and the boom descending speed is the fastest. When the movable arm descends, the oil return amount of the large cavity of the movable arm is adjusted according to different types, different working conditions and the like, the Sc1 current is adjusted, the purpose of different oil return areas is achieved, and therefore the action performance of the movable arm is optimal.

Bucket cylinder 330 actuates the bucket to dig a single action

For a single pressure system, the CKI in the electronic controller 400 receives a signal of the digging action of the bucket of the complete machine, which may be a remote control signal or an electrical signal converted from other devices, such as an electric control handle. The electronic controller 400 processes the signal received by the CKI, and adjusts the output signal of the Sc31 signal port according to the value of the signal, so that the displacement of the variable drive device 100 is increased; meanwhile, the output signal size of the Sc29 signal port is adjusted according to the value of the CKI signal; the current of the Sc29 signal port is increased to reach the i '1 position or directly reach the position greater than or equal to i' 3, and at the moment, the pressure is quickly built in the main pressure oil passage 210; meanwhile, the current of Sc10 is adjusted, and after the current of Sc10 reaches a certain value (greater than or equal to i1), an oil inlet passage of a large cavity of the bucket oil cylinder is opened; meanwhile, the current of Sc11 is adjusted, and after the current of Sc11 reaches a certain value (greater than or equal to i1), the oil return path of the small cavity of the bucket oil cylinder is opened; in this way, the bucket excavation operation is realized. When the bucket excavation action signal requires that the bucket excavation action is slow, as shown in fig. 3, the input current of S10 is i2, the flow rate of pressure oil to the large cavity of the bucket is small, and the bucket excavates slowly; when the bucket excavation action signal requires an increase in the bucket excavation action, as shown in fig. 3, the input current of S10 is i3, the flow rate of the pressure oil to the bucket large chamber increases, and the bucket excavation speed increases; when the bucket requires the fastest speed for digging, as shown in fig. 3, the input current of the S10 is at imax, the pressure oil flow to the large cavity of the bucket is the largest, and the bucket has the fastest digging speed. When the bucket excavates, the oil return amount of the small cavity of the bucket adjusts the Sc11 current according to different models, different working conditions, different action speed requirements and the like, so that the purpose of different oil return areas is achieved, and the bucket action performance is optimal.

For a multi-pressure system, the electronic controller 400 processes the signal received by CKI, and adjusts the Sc31 signal port and the Sc32 output signal according to the value of the signal, so that the displacement of the variable displacement drive 100 is increased; meanwhile, the output signal size of the Sc29 signal port is adjusted according to the value of the CKI signal; the current of the Sc29 signal port is increased to reach the position i '1 or directly reach the position more than or equal to i' 3, and at the moment, the pressure is quickly built in the second main pressure oil channel; meanwhile, the current of Sc10 is adjusted, and after the current of Sc10 reaches a certain value (greater than or equal to i1), an oil inlet passage of a large cavity of the bucket oil cylinder is opened; meanwhile, the current of Sc11 is adjusted, and after the current of Sc11 reaches a certain value (greater than or equal to i1), the oil return path of the small cavity of the bucket oil cylinder is opened; in this way, the bucket excavation operation is realized. Particularly, a high-pressure large-flow normally-closed proportional solenoid valve is arranged between the first main pressure oil passage and the second main pressure oil passage, when the two pressure oil passages, namely the first main pressure oil passage and the second main pressure oil passage, need to be communicated due to factors such as overall system parameters and action time requirements, the oil return control valve S30 is electrified, the first main pressure oil passage quickly builds pressure, meanwhile, Sc0 is electrified, the confluence control valve S0 is opened, the first main pressure oil passage and the second main pressure oil passage are converged, and the discharge volumes of the two pumps are simultaneously supplied to the bucket cylinder. When the bucket excavation action signal requires that the bucket excavation action is slow, as shown in fig. 3, the input current of S10 is i2, the flow rate of pressure oil to the large cavity of the bucket is small, and the bucket excavates slowly; when the bucket excavation action signal requires an increase in the bucket excavation action, as shown in fig. 3, the input current of S10 is i3, the flow rate of the pressure oil to the bucket large chamber increases, and the bucket excavation speed increases; when the bucket requires the fastest speed for digging, as shown in fig. 3, the input current of the S10 is at imax, the pressure oil flow to the large cavity of the bucket is the largest, and the bucket has the fastest digging speed. When the bucket excavates, the bucket loculus oil return volume according to different models, different operating modes etc. adjusts the Sc11 electric current, reaches different oil return area purposes to make the bucket action performance reach the optimum.

Bucket cylinder 330 drives bucket to unload in a single motion

For a single pressure system, the CKO in the electronic controller 400 receives a complete machine bucket discharge motion signal, which may be a remote control signal or an electrical signal converted from other devices, such as an electronic control handle. The electronic controller 400 processes the signal received by the CKO, and adjusts the output signal of the Sc31 signal port according to the value of the signal, so that the displacement of the variable drive device 100 is increased; meanwhile, the output signal size of the Sc29 signal port is adjusted according to the value of the CKO signal; the current of the Sc29 signal port is increased to reach the i '1 position or directly reach the position greater than or equal to i' 3, and at the moment, the pressure is quickly built in the main pressure oil passage 210; meanwhile, the current of Sc12 is adjusted, and after the current of Sc12 reaches a certain value (greater than or equal to i1), an oil inlet passage of a small cavity of the bucket oil cylinder is opened; meanwhile, the current of Sc9 is adjusted, and after the current of Sc9 reaches a certain value (greater than or equal to i1), an oil return path of a large cavity of the bucket oil cylinder is opened; therefore, the bucket discharging action is realized. When the bucket discharging action signal requires that the bucket discharging action is slow, as shown in fig. 3, the input current of S12 is at i2, the flow of pressure oil to the small cavity of the bucket is small, and the bucket discharges slowly; when the bucket unloading action signal requires that the bucket unloading action is accelerated, as shown in fig. 3, the input current of S12 is at i3, the flow of pressure oil to the small cavity of the bucket is increased, and the bucket unloading speed is accelerated; when the bucket requires the fastest speed to descend, as shown in fig. 3, the input current of the S12 is at imax, the pressure oil flow to the small cavity of the bucket is the largest, and the bucket is unloaded fastest. When the bucket is unloaded, the oil return amount of the large cavity of the bucket is adjusted according to different types, different working conditions, different descending speed requirements and the like, and the Sc9 current is adjusted to achieve the purpose of different oil return areas, so that the action performance of the bucket is optimal.

For a multi-pressure system, the electronic controller 400 processes the signal received by CKO, and adjusts the Sc31 signal port and the Sc32 output signal according to the value of the signal, so that the displacement of the variable displacement drive 100 is increased; meanwhile, the output signal size of the Sc29 signal port is adjusted according to the value of the CKO signal; the current of the Sc29 signal port is increased to reach the position i '1 or directly reach the position more than or equal to i' 3, and at the moment, the pressure is quickly built in the second main pressure oil channel; meanwhile, the current of Sc12 is adjusted, and after the current of Sc12 reaches a certain value (greater than or equal to i1), an oil inlet passage of a small cavity of the bucket oil cylinder is opened; meanwhile, the current of Sc9 is adjusted, and after the current of Sc9 reaches a certain value (greater than or equal to i1), an oil return path of a large cavity of the bucket oil cylinder is opened; therefore, the bucket discharging action is realized. Particularly, a high-pressure large-flow normally-closed proportional solenoid valve is arranged between the first main pressure oil passage and the second main pressure oil passage, when the two pressure oil passages, namely the first main pressure oil passage and the second main pressure oil passage, need to be communicated due to factors such as overall system parameters and action time requirements, the oil return control valve S30 is electrified, the first main pressure oil passage quickly builds pressure, meanwhile, Sc0 is electrified, the confluence control valve S0 is opened, the first main pressure oil passage and the second main pressure oil passage are converged, and the discharge volumes of the two pumps are simultaneously supplied to the bucket cylinder. When the bucket discharging action signal requires that the bucket discharging action is slow, as shown in fig. 3, the input current of S12 is at i2, the flow of pressure oil to the small cavity of the bucket is small, and the bucket discharges slowly; when the bucket unloading action signal requires that the bucket unloading action is accelerated, as shown in fig. 3, the input current of S12 is at i3, the flow of pressure oil to the small cavity of the bucket is increased, and the bucket unloading speed is accelerated; when the bucket requires the fastest discharging speed, as shown in fig. 3, the input current of the S12 is at imax, the pressure oil flow to the small cavity of the bucket is the largest, and the bucket is the fastest in discharging speed. When the bucket is unloaded, the oil return amount of the large cavity of the bucket is adjusted according to different types, different working conditions and the like, and the purpose of different oil return areas is achieved, so that the action performance of the bucket is optimal.

The bucket rod cylinder 320 drives the bucket rod to swing outwards in a single action

For a single pressure system, the CAO in the electronic controller 400 receives a signal of the outward swing of the bucket rod of the whole machine, and the signal may be a remote control signal or an electric signal converted from other devices, such as an electric control handle. The electronic controller 400 processes the signal received by the CAO, and adjusts the output signal of the Sc31 signal port according to the value of the signal, so that the displacement of the variable driving device 100 is increased; meanwhile, the output signal size of the Sc29 signal port is adjusted according to the value of the CAO signal; the current of the Sc29 signal port is increased to reach the i '1 position or directly reach the position greater than or equal to i' 3, and at the moment, the pressure is quickly built in the main pressure oil passage 210; meanwhile, the current of Sc8 is adjusted, and after the current of Sc8 reaches a certain value (greater than or equal to i1), an oil inlet passage of a small cavity of the bucket rod oil cylinder is opened; meanwhile, the current of the Sc5 is adjusted, and after the current of the Sc5 reaches a certain value (greater than or equal to i1), an oil return path of a large cavity of the bucket rod oil cylinder is opened; therefore, the outward swinging motion of the bucket rod is realized. When the outward swinging action signal of the bucket rod requires that the outward swinging action of the bucket rod is slow, as shown in fig. 3, the input current of S8 is at i2, the flow of pressure oil to a small cavity of the bucket rod is small, and the bucket rod unloads slowly; when the signal of the outward swinging of the bucket rod requires that the outward swinging of the bucket rod is accelerated, as shown in fig. 3, the input current of S8 is at i3, the flow of pressure oil to the small cavity of the bucket rod is increased, and the outward swinging speed of the bucket rod is accelerated; when the bucket rod is required to descend at the fastest speed, as shown in fig. 3, the input current of S8 is at imax, the flow of pressure oil to the small cavity of the bucket rod is the largest, and the outward swinging speed of the bucket rod is the fastest. When the bucket rod swings outwards, the oil return amount of the big cavity of the bucket rod is adjusted according to different models, different working conditions, different descending speed requirements and the like, the Sc5 current is adjusted, the purpose of different oil return areas is achieved, and therefore the action performance of the bucket rod is optimal.

For a multi-pressure system, the electronic controller 400 processes the signal received by the CAO, and adjusts the Sc31 signal port and the Sc32 output signal according to the value of the signal, so that the displacement of the variable drive device 100 is increased; meanwhile, the output signal size of the Sc30 is adjusted according to the value of the CAO signal; the current of the Sc30 is increased and reaches the position i '1 or is directly more than or equal to i' 3, and at the moment, the pressure is quickly built in the first main pressure oil passage; meanwhile, the current of Sc8 is adjusted, and after the current of Sc8 reaches a certain value (greater than or equal to i1), an oil inlet passage of a small cavity of the bucket rod oil cylinder is opened; meanwhile, the current of the Sc5 is adjusted, and after the current of the Sc5 reaches a certain value (greater than or equal to i1), an oil return path of a large cavity of the bucket rod oil cylinder is opened; therefore, the outward swinging motion of the bucket rod is realized. Particularly, a high-pressure large-flow normally-closed proportional solenoid valve is arranged between the first main pressure oil passage and the second main pressure oil passage, when the two pressure oil passages, namely the first main pressure oil passage and the second main pressure oil passage, need to be communicated due to factors such as overall system parameters and action time requirements, the oil return control valve S30 is electrified, the first main pressure oil passage quickly builds pressure, meanwhile, Sc0 is electrified, the confluence control valve S0 is opened, the first main pressure oil passage and the second main pressure oil passage are converged, and the discharge volumes of the two pumps are simultaneously supplied to the bucket rod oil cylinder. When the boom outward swing action signal requires that the boom outward swing action is slow, as shown in fig. 3, the input current of S8 is at i2, the flow of pressure oil to the small cavity of the boom is small, and the boom slowly swings outward; when the signal of the outward swinging of the bucket rod requires that the outward swinging of the bucket rod is accelerated, as shown in fig. 3, the input current of S8 is at i3, the flow of pressure oil to the small cavity of the bucket rod is increased, and the outward swinging speed of the bucket rod is accelerated; when the bucket rod needs to swing outward most quickly, as shown in fig. 3, the input current of S8 is at imax, the flow of pressure oil to the small cavity of the bucket rod is the largest, and the swing outward speed of the bucket rod is the fastest. When the bucket rod swings outwards, the oil return amount of the big cavity of the bucket rod is adjusted according to different models, different working conditions and the like, and the purpose of different oil return areas is achieved, so that the action performance of the bucket rod is optimal.

Single action of bucket arm cylinder 320 driving bucket arm to retract

For a single pressure system, the CAI in the electronic controller 400 receives a retraction signal from the bucket rod of the whole machine, which may be a remote control signal or an electrical signal converted from another device, such as an electronic control handle. The electronic controller 400 processes the signal received by the CAI, and adjusts the output signal of the Sc31 signal port according to the value of the signal, so that the displacement of the variable drive device 100 is increased; meanwhile, the output signal size of the Sc29 signal port is adjusted according to the value of the CAI signal; the current of the Sc29 signal port is increased to reach the i '1 position or directly reach the position greater than or equal to i' 3, and at the moment, the pressure is quickly built in the main pressure oil passage 210; meanwhile, the current of Sc6 is adjusted, and after the current of Sc6 reaches a certain value (greater than or equal to i1), an oil inlet passage of a large cavity of the bucket rod oil cylinder is opened; meanwhile, the current of the Sc7 is adjusted, and after the current of the Sc7 reaches a certain value (greater than or equal to i1), an oil return path of a small cavity of the arm cylinder is opened; thus, the bucket rod is retracted. When the boom retraction operation signal requires that the boom retraction operation is slow, as shown in fig. 3, the input current of S6 is i2, the flow rate of the pressure oil to the boom large chamber is small, and the boom excavates slowly; when the arm retraction operation signal requires an increase in the arm retraction operation, as shown in fig. 3, the input current of S6 is i3, the flow rate of the pressure oil to the arm large chamber increases, and the arm retraction speed increases; when the arm is required to dig at the fastest speed, as shown in fig. 3, the input current of S6 is imax, the flow rate of the pressure oil to the arm large chamber is the largest, and the speed of the arm retraction is the fastest. When the bucket rod is internally received, the oil return amount of the small cavity of the bucket rod is adjusted according to different models, different working conditions, different action speed requirements and the like, the Sc7 current is adjusted, the purpose of different oil return areas is achieved, and therefore the action performance of the bucket rod is optimal.

For a multi-pressure system, the electronic controller 400 processes the signal received by the CAI, and adjusts the Sc31 signal port and the Sc32 output signal according to the value of the signal, so that the displacement of the variable displacement drive 100 is increased; meanwhile, the output signal size of the Sc30 is adjusted according to the value of the CAI signal; the current of the Sc30 is increased and reaches the position i '1 or is directly more than or equal to i' 3, and at the moment, the pressure is quickly built in the first main pressure oil passage; meanwhile, the current of Sc6 is adjusted, and after the current of Sc6 reaches a certain value (greater than or equal to i1), an oil inlet passage of a large cavity of the bucket rod oil cylinder is opened; meanwhile, the current of the Sc7 is adjusted, and after the current of the Sc7 reaches a certain value (greater than or equal to i1), an oil return path of a small cavity of the arm cylinder is opened; thus, the bucket rod is retracted. Particularly, a high-pressure large-flow normally-closed proportional solenoid valve is arranged between the first main pressure oil passage and the second main pressure oil passage, when the two pressure oil passages, namely the first main pressure oil passage and the second main pressure oil passage, need to be communicated due to factors such as overall system parameters and action time requirements, the oil return control valve S30 is electrified, the first main pressure oil passage quickly builds pressure, meanwhile, Sc0 is electrified, the confluence control valve S0 is opened, the first main pressure oil passage and the second main pressure oil passage are converged, and the discharge volumes of the two pumps are simultaneously supplied to the bucket rod oil cylinder. When the boom retraction operation signal requires that the boom retraction operation is slow, as shown in fig. 3, the input current of S6 is i2, the flow rate of the pressure oil to the boom large chamber is small, and the boom is retracted slowly; when the arm retraction operation signal requires an increase in the arm retraction operation, as shown in fig. 3, the input current of S6 is i3, the flow rate of the pressure oil to the arm large chamber increases, and the arm retraction speed increases; when the arm is required to be retracted within the maximum speed, as shown in fig. 3, the input current of S6 is at imax, the flow rate of the pressure oil to the large cavity of the arm is maximum, and the retraction speed of the arm is the maximum. When the bucket rod is received internally, the oil return amount of the small cavity of the bucket rod is adjusted according to different models, different working conditions and the like, and the Sc7 current is adjusted to achieve the purpose of different oil return areas, so that the action performance of the bucket rod is optimal.

The rotary motor 340 drives the left rotary single action

For a single pressure system, the CWL signal port in the electronic controller 400 receives a left turn signal of the whole machine, which may be a remote control signal or an electrical signal converted from another device, such as an electronic control handle. The electronic controller 400 processes the signal received by the CWL signal port, and adjusts the output signal of the Sc31 signal port according to the value of the signal, so that the displacement of the variable drive device 100 is increased; meanwhile, the output signal size of the Sc29 signal port is adjusted according to the signal value of the CWL signal port; the current of the Sc29 signal port is increased to reach the i '1 position or directly reach the position greater than or equal to i' 3, and at the moment, the pressure is quickly built in the main pressure oil passage 210; meanwhile, the current of Sc26 is adjusted, and after the current of Sc26 reaches a certain value (greater than or equal to i1), an oil inlet path of a left rotary oil inlet of the rotary motor is opened; meanwhile, the current of Sc27 is adjusted, and after the current of Sc27 reaches a certain value (greater than or equal to i1), an oil return path of the rotary motor is opened; in the above, the left-turn operation is realized. When the left rotation action signal requires that the left rotation action is slow, as shown in fig. 3, the input current of S26 is at i2, the flow of pressure oil to the oil port of the left rotation motor is small, and the whole machine rotates slowly; when the left-turning motion signal requires acceleration of the left-turning motion, as shown in fig. 3, the input current of S26 is i3, the flow rate of the pressure oil to the left-turning oil port of the turning motor is increased, and the left-turning speed is accelerated; when the requirement for left rotation is fastest, as shown in fig. 3, the input current of S26 is at imax, the flow of pressure oil to the left rotation oil port is the largest, and the left rotation speed is fastest. When the rotary oil return port rotates left, the oil return amount of the rotary oil return port is adjusted according to different machine types, different working conditions, different action speed requirements and the like, so that the aim of different oil return areas is fulfilled, and the rotary action performance is optimized.

For a multi-pressure system, the electronic controller 400 processes the signal received by the CWL, and adjusts the Sc31 signal port, the Sc32 output signal, based on the magnitude of the signal value, such that the displacement of the variable displacement drive 100 is increased; meanwhile, the output signal size of the Sc30 is adjusted according to the value of the CWL signal; the current of the Sc30 is increased and reaches the position i '1 or directly reaches the position more than or equal to i' 3, and at the moment, the pressure is quickly built in the second main pressure oil passage; meanwhile, the current of Sc26 is adjusted, and after the current of Sc26 reaches a certain value (greater than or equal to i1), a left rotary oil inlet oil way of the rotary motor is opened; meanwhile, the current of Sc27 is adjusted, and after the current of Sc27 reaches a certain value (greater than or equal to i1), a left rotary oil return oil way of the rotary motor is opened; therefore, the left rotation action of the whole machine is realized. Particularly, a high-pressure large-flow normally-closed proportional solenoid valve is arranged between the first main pressure oil passage and the second main pressure oil passage, when the two pressure oil passages, namely the first main pressure oil passage and the second main pressure oil passage, need to be communicated due to factors such as overall system parameters and action time requirements, the oil return control valve S30 is electrified, the first main pressure oil passage quickly builds pressure, meanwhile, Sc0 is electrified, the confluence control valve S0 is opened, the first main pressure oil passage and the second main pressure oil passage are converged, and the discharge volumes of the two pumps are simultaneously supplied to the boom cylinder. When a left rotation action signal of the rotation motor needs to make the left rotation action of the rotation motor slower, as shown in fig. 3, the input current of S26 is at i2, the flow rate of pressure oil to the left rotation oil inlet of the rotation motor is smaller, and the whole machine rotates left slowly; when the left rotation action signal of the rotary motor needs to accelerate the left rotation action of the whole machine, as shown in fig. 3, the input current of S26 is at i3, the flow of pressure oil to the left rotation oil inlet of the rotary motor is increased, and the left rotation speed of the rotary motor is accelerated; when the whole machine requires the fastest speed to rotate left, as shown in fig. 3, the input current of S26 is at imax, the flow of pressure oil to the left rotation oil inlet of the rotation motor is the largest, and the left rotation speed of the rotation motor is the fastest. When the rotary motor rotates left, the left rotation oil return amount of the rotary motor adjusts the Sc27 current according to different models, different working conditions and the like, so that the purpose of different oil return areas is achieved, and the action performance of the moving arm is optimal.

The rotary motor 340 drives the right rotary single action

And when the right rotation acts, the control strategy is similar to the left rotation. The whole machine right-turning action signal receiving opening is CWR, the Sc28 is used for controlling the area of a motor oil inlet and the oil inlet flow during right turning, and the Sc25 is used for controlling the area of a motor oil return opening and the oil return flow during right turning.

Left-walking motor 350 drives left-walking forward single action

The CTLF signal port in the electronic controller 400 receives the left walking forward motion signal of the whole machine, which may be a remote control signal or an electrical signal converted by other devices, such as an electronic control handle. The electronic controller 400 processes the signal received by the CTLF signal port, and adjusts the output signal of the Sc31 signal port according to the value of the signal, so that the displacement of the variable driving device 100 is increased; meanwhile, the output signal size of the Sc29 signal port is adjusted according to the signal value of the CTLF signal port; the current of the Sc29 signal port is increased to reach the i '1 position or directly reach the position greater than or equal to i' 3, and at the moment, the pressure is quickly built in the main pressure oil passage 210; meanwhile, the current of the Sc24 signal port is adjusted, and when the Sc24 current reaches a certain value (greater than or equal to i1), the oil inlet path of the forward oil inlet of the left traveling motor is opened; meanwhile, the current of Sc21 is adjusted, and after the current of Sc21 reaches a certain value (greater than or equal to i1), an oil return path of the rotary motor is opened; in this way, the left-side walking forward motion is realized. When the left walking forward motion signal requires that the left walking forward motion is slow, as shown in fig. 3, the input current of S24 is at i2, the flow rate of pressure oil to the front oil inlet of the left walking motor is small, and the left walking motor rotates slowly; when the left-hand forward motion signal requires acceleration of the left-hand forward motion, as shown in fig. 3, the input current of S24 is i3, the flow rate of the pressure oil to the forward oil port of the travel motor increases, and the rotation speed of the travel motor increases; when the left traveling motor is required to be the fastest, as shown in fig. 3, the input current of S24 is at imax, the flow rate of pressure oil to the front oil inlet of the left traveling motor is the largest, and the rotation speed of the left traveling motor is the fastest. When the left-hand walking vehicle advances, the oil return amount of the oil return port of the rotary motor adjusts the Sc21 current according to different models, different working conditions, different action speed requirements and the like, so as to achieve the purpose of different oil return areas, thereby enabling the walking action performance to be optimal.

For a multi-pressure system, the electronic controller 400 processes signals received by the CTLF signal port, and adjusts output signals of the Sc31 signal port and the Sc32 signal port according to the value of the signals, so that the displacement of the variable displacement driving device 100 is increased; meanwhile, the output signal size of the Sc30 signal port is adjusted according to the signal value of the CTLF signal port; the current of the Sc30 signal port is increased to reach the position i '1 or directly reach the position more than or equal to i' 3, and at the moment, the pressure is quickly built in the second main pressure oil channel; meanwhile, the current of the Sc24 signal port is adjusted, and after the current of the Sc24 signal port reaches a certain value (greater than or equal to i1), the oil inlet path of the left traveling motor is opened; meanwhile, the current of the Sc21 is adjusted, and after the current of the Sc21 signal port reaches a certain value (greater than or equal to i1), the oil return path of the left traveling motor is opened; in this way, the left-side walking forward motion is realized. Particularly, a high-pressure large-flow normally-closed proportional solenoid valve is arranged between the first main pressure oil passage and the second main pressure oil passage, when the two pressure oil passages, namely the first main pressure oil passage and the second main pressure oil passage, need to be communicated due to factors such as overall system parameters and action time requirements, the oil return control valve S30 is electrified, the first main pressure oil passage quickly builds pressure, meanwhile, Sc0 is electrified, the confluence control valve S0 is opened, the first main pressure oil passage and the second main pressure oil passage are converged, and the discharge volumes of the two pumps are simultaneously supplied to the left walking oil cylinder. When the left-traveling forward motion signal requires that the left-traveling forward motion is slow, as shown in fig. 3, the input current of S2 is at i2, the flow of pressure oil to the left-traveling forward oil inlet is small, and the left-traveling slow motion is performed; when the left-traveling forward motion signal requires that the left-traveling forward motion is accelerated, as shown in fig. 3, the input current of S24 is at i3, the flow rate of pressure oil to the left-traveling forward oil inlet is increased, and the left-traveling forward speed is accelerated; when the left-hand walking requires the fastest speed to advance, as shown in fig. 3, the input current of S24 is at imax, the flow rate of the pressure oil to the left-hand walking motor is the largest, and the left-hand walking advance speed is the fastest. When the left-hand walking is carried out, the forward oil return amount of the left-hand walking motor is adjusted according to different models, different working conditions and the like, so that the purpose of different oil return areas is achieved, and the left-hand walking action performance is optimal.

Left-travel motor 350 drives left-travel backward single action

When the left walking moves backwards, the control strategy is similar to the left walking moves forwards. The left walking and retreating action signal receiving port of the whole machine is CTLB, Sc22 is used for controlling the area of the forward oil inlet and the oil inlet flow of the left walking motor, and Sc23 is used for controlling the area of the forward oil return port and the oil return flow of the left rotary motor.

Right walking motor 360 drives right walking forward single action

When the right walking moves forward, the control strategy is similar to the left walking and moving forward. The whole machine right walking forward motion signal receiving port is CTRF, Sc20 is used for controlling the area of a forward oil inlet and the oil inlet flow of the right walking motor, and Sc18 is used for controlling the area of a forward oil return port and the oil return flow of the right walking motor.

Right walking motor 360 drives right walking backward single action

When the right walking moves backwards, the control strategy is similar to the left walking moves forwards. The receiving port of the complete machine right-walking backward movement action signal is CTRB, Sc18 is used for controlling the area of the forward oil inlet of the right-walking motor and the oil inlet flow, and Sc19 is used for controlling the area of the forward oil return port of the right-walking motor and the oil return flow.

Standby function

The working oil port of the electrohydraulic control device 200 can reserve a spare oil port 370 for function expansion, and meanwhile, a related signal receiving and outputting port is reserved in the electronic controller 400.

Composite motion

The excavator needs compound action, namely two or more than two single actions act simultaneously, the compound action mainly comprises: a boom raising + bucket digging compound action, a boom raising + swing compound action, a boom raising + arm in-drawing compound action, a boom raising + arm out-swinging compound action, a boom raising + single-traveling, a boom lowering + bucket compound action, a boom lowering + swing compound action, a boom lowering + arm in-drawing compound action, a boom lowering + arm out-swinging compound action, a boom lowering + single-traveling, a bucket digging + swing, a bucket digging + arm in-drawing, the method comprises the steps of digging a bucket, swinging a bucket rod outwards, unloading the bucket, turning the bucket, unloading the bucket, drawing the bucket rod inwards, unloading the bucket, swinging the bucket rod outwards, turning the bucket rod inwards, turning the bucket rod outwards, swinging the bucket rod outwards, walking the bucket in a single line, walking the rotation in a single line, walking the bucket in a double line, walking the movable arm, the bucket rod, the bucket and the turning.

All the composite actions take the coordination of the whole machine into consideration, and for the actions participating in the composite actions, the single-action control strategy described above is taken as a basic control strategy, on the basis of the basic control strategy, the electronic controller 400 carries out intelligent forced intervention on the electric input signals of the relevant proportional solenoid valves according to the configuration of the whole machine, load signals and the like, and the priority of the forced intervention is greater than that of the single-action control strategy for controlling the corresponding proportional solenoid valves.

For example, when a certain machine performs a combined action of boom raising and bucket digging, and the flow demand for boom raising is greater, the electronic controller 400 comprehensively processes the overall configuration, signals related to cc1, cc2, cc5 and cc6, and the overall maneuverability demand, and performs internal forcible intervention on the proportional electromagnetic valves S2, S3, S10 and S11 through Sc2, Sc3, Sc10 and Sc11, so that the oil inlet amount of the large cavity of the bucket cylinder is reduced, and more flow is supplied to the large cavity of the boom cylinder.

Specifically, when unmanned autonomous driving is performed, the CBU, CBD, CKI, CKO, CAI, CAO, CWL, CWR, CTLF, CTLB, CTRB, CTRF, etc. in the electronic controller 400 may not receive signals, but output signals to the current input port of the proportional solenoid valve according to other input signals of the whole machine and an internal program.

Optionally, a boom potential energy recovery module during boom descending and a potential energy recovery module during swing braking are added to the system. When the movable arm descends, the pressure of the large cavity of the movable arm is in a high-pressure state under the action of the whole machine and a load. As shown in fig. 7, an energy recovery device 500 is added to the boom large chamber oil passage, and the energy recovery device 500 includes an energy recovery check valve 510 and an energy recovery control valve 520. The pressure oil at the time of boom lowering may be recycled to the main pressure oil passage 210 or used for another function. Accordingly, control output signal S33 is added to electronic controller 400.

Optionally, a potential energy recovery module during slewing braking is added to the system. During rotary braking, the pressure of the return oil circuit of the rotary motor is instantaneously increased to reach an overflow state. An energy recovery device 500 is added to the oil circuit of the return working oil port of the rotary motor. The pressure oil at the time of the swing braking may be recycled to the main pressure oil passage 210, or used in another function. Accordingly, control output signal S34 is added to electronic controller 400.

The excavator electro-hydraulic control method provided by the embodiment is suitable for the excavator electro-hydraulic control system, the technical characteristics of the excavator electro-hydraulic control system are also suitable for the excavator electro-hydraulic control method, and the technical characteristics of the excavator electro-hydraulic control system are not described repeatedly. The excavator electro-hydraulic control method in the embodiment has the advantages of the excavator electro-hydraulic control system, and the advantages of the excavator electro-hydraulic control system disclosed above are not described repeatedly.

According to the excavator electro-hydraulic control system and the excavator electro-hydraulic control method, the whole excavator receives an external instruction, the external instruction is processed by the electronic controller 400, the instruction is sent to the electro-hydraulic control device 200, and the action of the whole excavator is controlled by controlling the on-off of the proportional solenoid valve. Meanwhile, the load of the whole machine is fed back to the electronic controller 400 through the load pressure sensor 380, and the electronic controller 400 processes relevant signals and adjusts the input signal of the proportional solenoid valve. Has the following characteristics:

energy conservation: the excavator electro-hydraulic control system can realize accurate control; when the system is not in action, the displacement of the variable driving device 100 is reduced, and meanwhile, the main pressure oil channel 210 is directly connected with return oil through a normally open high-pressure large-flow proportional electromagnetic valve, namely the return oil control valve 240, so that the pressure of a pump port is small, and the energy consumption of the whole machine is small.

The controllability is good: in the excavator electro-hydraulic control system of the embodiment, the load ports are independently controlled, for example, the oil inlet and the oil return of the large cavity and the oil return of the movable arm oil cylinder can be separately controlled, rather than the oil inlet and the oil return in the traditional hydraulic system having a fixed proportional relation, on the basis of the parameters of the whole excavator, the load pressure sensor 380 is used for detecting the real-time load pressure and transmitting the real-time load pressure to the electronic controller 400, and the whole excavator is subjected to dry intelligent control, so that the controllability of the whole excavator is greatly improved.

The response is quick: the excavator electro-hydraulic control system of this embodiment, for example, the response of proportional solenoid valve is less than 50ms, and because the through flow area from main pressure oil duct 210 to oil return passage 220 is big when not working, consequently the minimum discharge capacity of pump can increase, and does not increase the oil consumption apparently, and this just makes the complete machine need the action, and system flow can promote rapidly, and complete machine response speed promotes by a wide margin.

Intelligence: in this embodiment, the control of the excavator is mainly performed by the conventional hydraulic control, and is converted into the electric control for large-scale lifting, so that the load signals are collected in real time. The excavator electro-hydraulic control system can be applied to a manually operated complete machine and can also be applied to a remotely operated and automatically operated complete machine.

The family scope of the whole machine is wide: in the conventional excavator, basically, each machine type has a main control valve different from other machine types, and the electro-hydraulic control device 200 can adapt to different machine types through program adjustment of the electronic controller 400.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The excavator electro-hydraulic control system is characterized by comprising a variable driving device, an electro-hydraulic control device and an execution device;

2. The excavator electro-hydraulic control system of claim 1 wherein the implement includes a first oil chamber and a second oil chamber;

3. The excavator electro-hydraulic control system of claim 2, further comprising an electronic controller and a pressure sensor electrically connected to the electronic controller;

4. The electro-hydraulic control system of an excavator of claim 2 wherein the actuator comprises one or more of a boom cylinder, an arm cylinder, a bucket cylinder, a swing motor, a left travel motor and a right travel motor.

5. The excavator electro-hydraulic control system of claim 1, wherein the working oil port control unit comprises a first working oil port control valve, a second working oil port control valve and a working oil port check valve;

6. The excavator electrohydraulic control system of claim 5, wherein the first working oil port control valve and the second working oil port control valve are respectively a normally closed high-pressure large-flow proportional solenoid valve or a normally closed high-pressure large-flow valve consisting of a proportional solenoid valve and a valve rod;

and/or an oil outlet of the working oil port control unit is connected with a load pressure sensor, and the load pressure sensor is used for acquiring a pressure signal of the execution device.

7. The excavator electro-hydraulic control system of claim 1, wherein the number of the main pressure oil passages is plural; the main pressure oil passages are communicated through one or more confluence control valves;

8. The excavator electro-hydraulic control system of claim 1, comprising an energy recovery device; the energy recovery device comprises an energy recovery one-way valve and an energy recovery control valve;

9. The excavator electro-hydraulic control system of claim 1, wherein the variable drive is a variable displacement pump with adjustable displacement; the external input variable of the variable pump is an electric signal or a hydraulic signal; one or more outlets of the variable pumps are communicated with the main pressure oil channel;

10. An excavator electro-hydraulic control method, which is applicable to the excavator electro-hydraulic control system of claim 3, and comprises the following steps: