Loading hydraulic system and working method

Abstract

The invention belongs to the field of hydraulic systems, and relates to a loading hydraulic system and a working method. Comprising a loading hydraulic cylinder, a first hydraulic control reversing valve, a second hydraulic control reversing valve, a first throttling valve, a second throttling valve, a first one-way valve, a second one-way valve, an electromagnetic reversing valve, a servo valve and an oil filter. According to the loading force output requirement, the output loading force is adjusted by setting the working mode of the parallel loading hydraulic system, large-range loading force output control is achieved, the precision of the loading force is guaranteed, the output power is reasonably matched according to the requirement, and energy waste is avoided. With the help of the application, a passive load can be simulated to complete passive loading and running-in tests. According to the invention, the output loading force can be adjusted by setting the working mode of the parallel loading hydraulic system according to the loading requirement, and the loading force output with different specifications and meeting the precision in a large range is realized; the number of loading subsystems participating in work can be adjusted according to needs, loading power is supplied according to needs, and the system is more efficient and energy-saving.

Description

Technical Field

[0001] The present application belongs to the field of hydraulic systems and relates to a loading hydraulic system and a working method. Background Art

[0002] After the hydraulic actuator is assembled, it needs to undergo a running-in test and a loading test to ensure that it meets the design requirements. Usually, a loading test system is used to provide the required simulated load for load spectrum loading tests.

[0003] The loading test is carried out according to the load spectrum of the actual working of the hydraulic cylinder, which often includes different load combinations, which means that the loading test system needs to output different loading forces to meet the loading requirements. In addition, building a loading test system often requires a lot of resources. Hydraulic cylinders of different specifications often share a set of loading test systems for loading tests, which requires the loading test system to have a wide range of loading force output capabilities. Even if the use of large-sized loading cylinders can meet the loading requirements of large loading forces, when providing small loading forces, it faces the problem of loading accuracy that cannot meet the requirements and low energy efficiency. Summary of the invention

[0004] The present application provides a parallel loading hydraulic system, which adjusts the output loading force by setting the working mode of the parallel loading hydraulic system according to the loading force output requirement, and realizes a wide range of loading force output control, which not only ensures the accuracy of the loading force, but also reasonably matches the output power according to the requirements to avoid energy waste. With the help of this application, passive loading and running-in tests can also be completed by simulating passive loads.

[0005] Purpose of the Invention

[0006] In order to solve the above problems, the present invention provides a parallel loading hydraulic system and working method, which can output a wide range of loading forces with accurate accuracy, realize active loading and passive loading functions, and is more energy-efficient.

[0007] Technical Solution

[0008] The present invention is achieved through the following technical solutions:

[0009] A loading hydraulic system comprises a loading hydraulic cylinder, a first hydraulically controlled reversing valve, a second hydraulically controlled reversing valve, a first throttle valve, a second throttle valve, a first check valve, a second check valve, an electromagnetic reversing valve, a servo valve, and an oil filter;

[0010] The loading hydraulic cylinder includes a first working chamber and a second working chamber, a first hydraulically controlled reversing valve is arranged between the system return oil and the first working chamber of the loading hydraulic cylinder, and a second hydraulically controlled reversing valve is arranged between the system return oil and the second working chamber of the loading hydraulic cylinder; a first throttle valve is arranged between the system return oil and the first hydraulically controlled reversing valve, and a second throttle valve is arranged between the system return oil and the second hydraulically controlled reversing valve; a first check valve is connected in parallel at both ends of the first throttle valve, and the first check valve allows oil to enter the first working chamber of the loading hydraulic cylinder from the system return oil through the first check valve; a second check valve is connected in parallel at both ends of the second throttle valve, and the second check valve allows oil to enter the second working chamber of the loading hydraulic cylinder from the system return oil through the second check valve;

[0011] Furthermore, the system also includes an electromagnetic reversing valve, which is a two-position three-way valve, wherein the control port C of the electromagnetic reversing valve is simultaneously connected to the control oil ports of the first hydraulically controlled reversing valve and the second hydraulically controlled reversing valve, the pressure oil port P of the electromagnetic reversing valve is connected to the system oil inlet, and the return oil port T of the electromagnetic reversing valve is connected to the system oil return;

[0012] When the electromagnet of the electromagnetic reversing valve is not energized, the control port C of the electromagnetic reversing valve is connected to the oil return port T, the control oil ports of the first hydraulically controlled reversing valve and the second hydraulically controlled reversing valve are connected to the system oil return through the electromagnetic reversing valve, the first working chamber of the loading hydraulic cylinder is connected to the system oil return through the first hydraulically controlled reversing valve, and the second working chamber of the loading hydraulic cylinder is connected to the system oil return through the second hydraulically controlled reversing valve;

[0013] When the electromagnet of the electromagnetic reversing valve is energized, the pressure oil port P of the electromagnetic reversing valve is connected to the control port C, the control oil ports of the first hydraulically controlled reversing valve and the second hydraulically controlled reversing valve are connected to the system oil inlet through the electromagnetic reversing valve, the first hydraulically controlled reversing valve disconnects the oil path between the first working chamber of the loading hydraulic cylinder and the system oil return, and the second hydraulically controlled reversing valve disconnects the oil path between the second working chamber of the loading hydraulic cylinder and the system oil return;

[0014] Furthermore, when actively loaded, it also includes a servo valve, the oil inlet of the servo valve is connected to the system oil inlet, the oil return port of the servo valve is connected to the system oil return, the first working oil port of the servo valve is connected to the first working chamber of the loading hydraulic cylinder, the second working oil port of the servo valve is connected to the second working chamber of the loading hydraulic cylinder, and the servo valve adjusts the loading direction and speed;

[0015] Further, the throttle holes of the first throttle valve and the second throttle valve can be adjusted by a proportional solenoid;

[0016] Furthermore, the loading hydraulic cylinder is connected with a position sensor and a force sensor, which can provide loading displacement and loading force feedback information;

[0017] Furthermore, an oil filter is provided between the system oil inlet and the servo valve oil inlet to prevent the servo valve from being clogged by contaminants;

[0018] Furthermore, when a large loading force is required, the above-mentioned loading hydraulic systems are connected in parallel as required to provide the required loading capacity;

[0019] Furthermore, after multiple loading hydraulic systems are connected in parallel, the electromagnets of the electromagnetic reversing valves of the loading hydraulic systems that need to provide loading force are energized, and the electromagnets of the electromagnetic reversing valves of the loading hydraulic systems that do not need to provide loading force are not energized, thereby realizing the parallel loading function;

[0020] A working method of a parallel loading hydraulic system, including an active loading method and a passive loading method:

[0021] Active loading method, during active loading, the electromagnet of the electromagnetic reversing valve of the hydraulic loading system that needs to provide active loading force is energized, thereby cutting off the connecting oil path between the two working chambers of the loading hydraulic cylinder and the system return oil, and the electromagnet of the electromagnetic reversing valve of the hydraulic loading system that does not need to provide active loading force is not energized, so that the two working chambers of the loading hydraulic cylinder of the hydraulic loading system that does not need to provide active loading force and the connecting oil path of the system return oil are connected, and the first throttle valve and the second throttle valve are adjusted to the maximum, so that the hydraulic loading system that does not need to provide loading force can follow freely; adjust the opening size and direction of the servo valve, so as to control the loading spectrum required by the loading hydraulic cylinder output;

[0022] Passive loading method: During passive loading, the electromagnet and servo valve of the electromagnetic reversing valve of the hydraulic loading system are powered off, so that the two working chambers of the loading hydraulic cylinder and the connecting oil circuit of the system return oil are connected, and the first throttle valve and the second throttle valve of the hydraulic loading system that does not need to provide passive loading force are adjusted to the maximum, so that the hydraulic loading system that does not need to provide passive loading force can move freely, and the throttle ports of the first throttle valve and the second throttle valve of the hydraulic loading system that needs to provide passive loading force are adjusted, so that the hydraulic loading system that needs to provide passive loading force can provide the required passive loading force. During passive loading, the oil flowing out of the working chamber of the loading hydraulic cylinder needs to pass through the throttle valve, and the damping force generated by the throttle valve provides the loading force, and the oil flowing into the working chamber of the loading hydraulic cylinder is replenished from the system return oil through the one-way valve.

[0023] The beneficial effects of this application are:

[0024] (1) The loading hydraulic system of the present invention has both active loading and passive loading functions. Active loading adjusts the required loading force by controlling the pressure, and passive loading controls the passive loading force by adjusting the oil throttling.

[0025] (2) The present invention can adjust the output loading force by setting the working mode of the parallel loading hydraulic system according to the loading requirements, so as to achieve a loading force output with a wide range of different specifications and with a high accuracy;

[0026] (3) The present invention can adjust the number of loading subsystems involved in the work as needed, and the loading power is supplied on demand, which is more efficient and energy-saving.

[0027] The present invention is suitable for a loading test system that needs to provide a linear loading function. It solves the contradiction between the range and accuracy matching of limited test resources to verify the loading requirements of electrostatic hydraulic actuators and electromechanical actuators of different specifications, ensures the provision of high-precision loading forces within different ranges, and can also simulate passive loads to complete passive loading and running-in tests. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of a single loading hydraulic system;

[0029] Figure 2 It is the schematic diagram of the parallel loading hydraulic system.

[0030] Among them, 1-loading hydraulic cylinder, 2.1-first hydraulically controlled reversing valve, 2.2-second hydraulically controlled reversing valve, 3.1-first throttle valve, 3.2-second throttle valve, 4.1-first one-way valve, 4.2-second one-way valve, 5-electromagnetic reversing valve, 6-servo valve, 7-oil filter. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical scheme and advantages of the implementation of the present invention clearer, the technical scheme in the embodiment of the present invention will be described in more detail below in conjunction with the drawings in the embodiment of the present invention. In the drawings, the same or similar reference numerals throughout represent the same or similar originals or elements with the same or similar functions. The described embodiments are part of the embodiments of the present invention, not all of the embodiments. The embodiments described below with reference to the drawings are exemplary and intended to be used to explain the present invention, and should not be construed as limitations on the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. The embodiments of the present invention are described in detail below in conjunction with the drawings.

[0032] like Figure 1 As shown,

[0033] A parallel loading hydraulic system includes a loading hydraulic cylinder, a first hydraulically controlled reversing valve, a second hydraulically controlled reversing valve, a first throttle valve, a second throttle valve, a first check valve, a second check valve, an electromagnetic reversing valve, a servo valve, and an oil filter; as needed, single loading hydraulic systems can be connected in parallel to provide the required loading capacity.

[0034] The parallel loading hydraulic system is equipped with a servo valve to adjust the loading direction and speed. An oil filter is provided between the system oil inlet and the servo valve oil inlet to prevent the servo valve from being blocked by contaminants.

[0035] The first hydraulically controlled reversing valve and the second hydraulically controlled reversing valve are respectively arranged between the two working chambers of the system return oil and the loading hydraulic cylinder. When there is no pressure in the control oil ports of the first hydraulically controlled reversing valve and the second hydraulically controlled reversing valve, the two working oil ports are connected; the control oil ports of the first hydraulically controlled reversing valve and the second hydraulically controlled reversing valve are connected to the control port of the electromagnetic reversing valve, the pressure oil port of the electromagnetic reversing valve is connected to the system oil inlet, and the return oil port of the electromagnetic reversing valve is connected to the system return oil; when the electromagnet of the electromagnetic reversing valve is not energized, the control port of the electromagnetic reversing valve and the return oil port are connected, and the first The control oil ports of the hydraulically controlled reversing valve and the second hydraulically controlled reversing valve are connected to the system oil return through the electromagnetic reversing valve, and the two working chambers of the loading hydraulic cylinder are connected to the system oil return through the first hydraulically controlled reversing valve and the second hydraulically controlled reversing valve respectively; when the electromagnet of the electromagnetic reversing valve is energized, the pressure oil port and the control port of the electromagnetic reversing valve are connected, and the control oil ports of the first hydraulically controlled reversing valve and the second hydraulically controlled reversing valve are connected to the system oil inlet through the electromagnetic reversing valve, and the first hydraulically controlled reversing valve and the second hydraulically controlled reversing valve disconnect the oil circuit between the two working chambers of the loading hydraulic cylinder and the system oil return;

[0036] A first throttle valve and a second throttle valve are respectively arranged between the system return oil and the first hydraulically controlled reversing valve and the second hydraulically controlled reversing valve to adjust the flow area of ​​the oil circuit connecting the two working chambers of the loading hydraulic cylinder and the system return oil; a first check valve and a second check valve are respectively connected in parallel at both ends of the first throttle valve and the second throttle valve, so that the oil can enter the two working chambers of the loading hydraulic cylinder from the system return oil through the first check valve and the second check valve.

[0037] In summary, the parallel loading hydraulic system of the present invention has a simple composition, and multiple loading hydraulic systems can be used in parallel according to the loading force output requirements. The output loading force can be adjusted by adjusting the working state of the parallel loading hydraulic system, and active loading and passive loading functions can be realized, which is efficient, convenient and simple to control.

[0038] Example

[0039] The present invention is achieved through the following technical solutions:

[0040] A loading hydraulic system comprises a loading hydraulic cylinder 1, a first hydraulically controlled reversing valve 2.1, a second hydraulically controlled reversing valve 2.2, a first throttle valve 3.1, a second throttle valve 3.2, a first non-return valve 4.1, a second non-return valve 4.2, an electromagnetic reversing valve 5, a servo valve 6, and an oil filter 7;

[0041] The loading hydraulic cylinder 1 comprises a first working chamber 1.1 and a second working chamber 1.2. A first hydraulically controlled reversing valve 2.1 is arranged between the system return oil and the first working chamber 1.1 of the loading hydraulic cylinder 1, and a second hydraulically controlled reversing valve 2.2 is arranged between the system return oil and the second working chamber 1.2 of the loading hydraulic cylinder 1; a first throttle valve 3.1 is arranged between the system return oil and the first hydraulically controlled reversing valve 2.1, and a second throttle valve 3.2 is arranged between the system return oil and the second hydraulically controlled reversing valve 2.2; a first check valve 4.1 is connected in parallel at both ends of the first throttle valve 3.1, and the first check valve 4.1 allows oil to enter the first working chamber 1.1 of the loading hydraulic cylinder 1 from the system return oil through the first check valve 4.1; a second check valve 4.2 is connected in parallel at both ends of the second throttle valve 3.2, and the second check valve 4.2 allows oil to enter the second working chamber 1.2 of the loading hydraulic cylinder 1 from the system return oil through the second check valve 4.2;

[0042] In a certain embodiment of the present invention, the system further comprises an electromagnetic reversing valve 5, which is a two-position three-way valve. The control port C of the electromagnetic reversing valve 5 is simultaneously connected to the control oil ports of the first hydraulically controlled reversing valve 2.1 and the second hydraulically controlled reversing valve 2.2. The pressure oil port P of the electromagnetic reversing valve 5 is connected to the system oil inlet, and the return oil port T of the electromagnetic reversing valve 5 is connected to the system oil return.

[0043] When the electromagnet of the electromagnetic reversing valve 5 is not energized, the control port C of the electromagnetic reversing valve 5 is connected to the oil return port T, the control oil ports of the first hydraulically controlled reversing valve 2.1 and the second hydraulically controlled reversing valve 2.2 are connected to the system oil return through the electromagnetic reversing valve 5, the first working chamber 1.1 of the loading hydraulic cylinder 1 is connected to the system oil return through the first hydraulically controlled reversing valve 2.1, and the second working chamber 1.2 of the loading hydraulic cylinder 1 is connected to the system oil return through the second hydraulically controlled reversing valve 2.2;

[0044] When the electromagnet of the electromagnetic reversing valve 5 is energized, the pressure oil port P of the electromagnetic reversing valve 5 is connected to the control port C, the control oil ports of the first hydraulically controlled reversing valve 2.1 and the second hydraulically controlled reversing valve 2.2 are connected to the system oil inlet through the electromagnetic reversing valve 5, the first hydraulically controlled reversing valve 2.1 disconnects the oil path between the first working chamber 1.1 of the loading hydraulic cylinder 1 and the system oil return, and the second hydraulically controlled reversing valve 2.2 disconnects the oil path between the second working chamber 1.2 of the loading hydraulic cylinder 1 and the system oil return;

[0045] In a certain embodiment of the present invention, when actively loading, it also includes a servo valve 6, the oil inlet of the servo valve 6 is connected to the system oil inlet, the oil return port of the servo valve 6 is connected to the system oil return, the first working oil port of the servo valve 6 is connected to the first working chamber 1.1 of the loading hydraulic cylinder 1, and the second working oil port of the servo valve 6 is connected to the second working chamber 1.2 of the loading hydraulic cylinder 1, and the servo valve 6 adjusts the loading direction and speed;

[0046] In a certain embodiment of the present invention, the throttle holes of the first throttle valve 3.1 and the second throttle valve 3.2 can be adjusted by proportional solenoids;

[0047] In a certain implementation case of the present invention, the loading hydraulic cylinder 1 is connected to a position sensor and a force sensor, which can provide loading displacement and loading force feedback information;

[0048] In a certain embodiment of the present invention, an oil filter 7 is provided between the system oil inlet and the servo valve oil inlet to prevent the servo valve from being blocked by contaminants;

[0049] In a certain implementation case of the present invention, when a large loading force is required, the above-mentioned loading hydraulic systems are connected in parallel as needed to provide the required loading capacity;

[0050] In a certain implementation case of the present invention, after multiple loading hydraulic systems are connected in parallel, the electromagnet of the electromagnetic reversing valve 5 of the loading hydraulic system that needs to provide loading force is energized, and the electromagnet of the electromagnetic reversing valve 5 of the loading hydraulic system that does not need to provide loading force is not energized, thereby realizing the parallel loading function;

[0051] A working method of a parallel loading hydraulic system, including an active loading method and a passive loading method:

[0052] Active loading method: during active loading, the electromagnet of the electromagnetic reversing valve 5 of the hydraulic loading system that needs to provide active loading force is energized, thereby cutting off the connecting oil path between the two working chambers of the loading hydraulic cylinder 1 and the system return oil, and the electromagnet of the electromagnetic reversing valve 5 of the hydraulic loading system that does not need to provide active loading force is not energized, so that the two working chambers of the loading hydraulic cylinder 1 of the hydraulic loading system that does not need to provide active loading force and the connecting oil path of the system return oil are connected, and the first throttle valve 3.1 and the second throttle valve 3.2 are adjusted to the maximum, so that the hydraulic loading system that does not need to provide loading force can follow freely; adjust the opening size and direction of the servo valve 6, so as to control the loading hydraulic cylinder 1 to output the required loading spectrum;

[0053] Passive loading method: During passive loading, the electromagnet and servo valve 6 of the electromagnetic reversing valve 5 of the hydraulic loading system are powered off, so that the two working chambers of the loading hydraulic cylinder 1 and the connecting oil circuit of the system return oil are connected, and the first throttle valve 3.1 and the second throttle valve 3.2 of the hydraulic loading system that does not need to provide passive loading force are adjusted to the maximum, so that the hydraulic loading system that does not need to provide passive loading force can move freely, and the throttle ports of the first throttle valve 3.1 and the second throttle valve 3.2 of the hydraulic loading system that needs to provide passive loading force are adjusted, so that the hydraulic loading system that needs to provide passive loading force can provide the required passive loading force. During passive loading, the oil flowing out of the working chamber of the loading hydraulic cylinder 1 needs to pass through the throttle valve, and the damping force generated by the throttle valve provides the loading force, and the oil flowing into the working chamber of the loading hydraulic cylinder 1 is replenished from the system return oil through the one-way valve.

[0054] It is understood by those skilled in the art that, unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as the general understanding of ordinary technicians in the field to which the present invention belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and unless defined as here, will not be interpreted with idealized or overly formal meanings. The specific implementation methods described above further describe the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the present invention. Within the spirit and principle of the present invention, any technician familiar with the profession may use the above disclosed technical content to change or modify it into an equivalent embodiment of equivalent changes for application in other fields, but any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the technical solution content of the present invention, any modification, equivalent replacement, improvement, etc., made according to the technical essence of the present invention, should be included in the protection scope of the present invention.

Claims

1. A loading hydraulic system, characterized in that: It includes a loading hydraulic cylinder, a first hydraulically controlled reversing valve, a second hydraulically controlled reversing valve, a first throttle valve, a second throttle valve, a first check valve, a second check valve, an electromagnetic reversing valve, a servo valve, and an oil filter; The loading hydraulic cylinder includes a first working chamber and a second working chamber, a first hydraulically controlled reversing valve is arranged between the system return oil and the first working chamber of the loading hydraulic cylinder, and a second hydraulically controlled reversing valve is arranged between the system return oil and the second working chamber of the loading hydraulic cylinder; a first throttle valve is arranged between the system return oil and the first hydraulically controlled reversing valve, and a second throttle valve is arranged between the system return oil and the second hydraulically controlled reversing valve; a first one-way valve is connected in parallel at both ends of the first throttle valve, and the first one-way valve allows oil from the system return oil to pass through the first one-way valve and enter the first working chamber of the loading hydraulic cylinder; a second one-way valve is connected in parallel at both ends of the second throttle valve, and the second one-way valve allows oil from the system return oil to pass through the second one-way valve and enter the second working chamber of the loading hydraulic cylinder.

2. The system according to claim 1, characterized in that It also includes an electromagnetic reversing valve, which is a two-position three-way valve. The control port C of the electromagnetic reversing valve is connected to the control oil ports of the first hydraulically controlled reversing valve and the second hydraulically controlled reversing valve at the same time. The pressure oil port P of the electromagnetic reversing valve is connected to the system oil inlet, and the return oil port T of the electromagnetic reversing valve is connected to the system oil return; When the electromagnet of the electromagnetic reversing valve is not energized, the control port C of the electromagnetic reversing valve is connected to the oil return port T, the control oil ports of the first hydraulically controlled reversing valve and the second hydraulically controlled reversing valve are connected to the system oil return through the electromagnetic reversing valve, the first working chamber of the loading hydraulic cylinder is connected to the system oil return through the first hydraulically controlled reversing valve, and the second working chamber of the loading hydraulic cylinder is connected to the system oil return through the second hydraulically controlled reversing valve; When the electromagnet of the electromagnetic reversing valve is energized, the pressure oil port P and the control port C of the electromagnetic reversing valve are connected, the control oil ports of the first hydraulically controlled reversing valve and the second hydraulically controlled reversing valve are connected to the system oil inlet through the electromagnetic reversing valve, the first hydraulically controlled reversing valve disconnects the oil path between the first working chamber of the loading hydraulic cylinder and the system return oil, and the second hydraulically controlled reversing valve disconnects the oil path between the second working chamber of the loading hydraulic cylinder and the system return oil.

3. The system according to claim 2, characterized in that When actively loaded, it also includes a servo valve, the oil inlet of the servo valve is connected to the system oil inlet, the oil return port of the servo valve is connected to the system oil return, the first working oil port of the servo valve is connected to the first working chamber of the loading hydraulic cylinder, and the second working oil port of the servo valve is connected to the second working chamber of the loading hydraulic cylinder. The servo valve adjusts the loading direction and speed.

4. The system according to claim 3, characterized in that The throttle holes of the first throttle valve and the second throttle valve are adjusted by proportional solenoids.

5. The system according to claim 4, characterized in that The loading hydraulic cylinder is connected with a position sensor and a force sensor to provide loading displacement and loading force feedback information.

6. The system according to claim 5, characterized in that An oil filter is provided between the system oil inlet and the servo valve oil inlet to prevent the servo valve from being clogged by contaminants.

7. The system according to claim 6, characterized in that When a large loading force is required, the above-mentioned loading hydraulic systems are connected in parallel as needed to provide the required loading capacity.

8. The system according to claim 7, characterized in that After multiple loading hydraulic systems are connected in parallel, the electromagnets of the electromagnetic reversing valves of the loading hydraulic systems that need to provide loading force are energized, while the electromagnets of the electromagnetic reversing valves of the loading hydraulic systems that do not need to provide loading force are not energized, thereby realizing the parallel loading function.

9. The working method of the system as claimed in claim 8, comprising an active loading method and a passive loading method: Active loading method, during active loading, the electromagnet of the electromagnetic reversing valve of the hydraulic loading system that needs to provide active loading force is energized, thereby cutting off the connecting oil path between the two working chambers of the loading hydraulic cylinder and the system return oil, and the electromagnet of the electromagnetic reversing valve of the hydraulic loading system that does not need to provide active loading force is not energized, so that the two working chambers of the loading hydraulic cylinder of the hydraulic loading system that does not need to provide active loading force and the connecting oil path of the system return oil are connected, and the first throttle valve and the second throttle valve are adjusted to the maximum, so that the hydraulic loading system that does not need to provide loading force can follow freely; adjust the opening size and direction of the servo valve, so as to control the loading spectrum required by the loading hydraulic cylinder output; Passive loading method, during passive loading, the electromagnet and servo valve of the electromagnetic reversing valve of the hydraulic loading system are powered off, so that the two working chambers of the loading hydraulic cylinder and the connecting oil circuit of the system return oil are connected, the first throttle valve and the second throttle valve of the hydraulic loading system that does not need to provide passive loading force are adjusted to the maximum, so that the hydraulic loading system that does not need to provide passive loading force can move freely, and the throttle ports of the first throttle valve and the second throttle valve of the hydraulic loading system that needs to provide passive loading force are adjusted so that the hydraulic loading system that needs to provide passive loading force can provide the required passive loading force; during passive loading, the oil flowing out of the working chamber of the loading hydraulic cylinder needs to pass through the throttle valve, and the damping force generated by the throttle valve provides the loading force, and the oil flowing into the working chamber of the loading hydraulic cylinder is replenished from the system return oil through the one-way valve.

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