A hydraulic loading system for semi-physical simulation platform of excavator

Abstract

The present invention discloses a hydraulic loading system for an excavator semi-physical simulation platform, comprising a loading pump group, a converging switching valve group, a boom-link loading valve group, a dipper-link loading valve group, a bucket-link loading valve group, a rotary-link loading valve group, a flow detection component, a pressure detection component, a multi-way valve, and an excavator power unit; the oil inlet of each multi-way valve is supplied with oil by the excavator power unit, the oil return flow of the boom-link, dipper-link, and bucket-link is supplied with oil by the loading pump group, the loading load pressure is simulated by the loading valve group, the return oil volume and return oil back pressure are controlled by the speed regulating valve of each loading valve group, and the rotary link controls the return oil volume and simulates the rotary load by the rotary loading valve group. The present invention adopts multiple pump groups for loading, has a large loading flow range, is highly versatile, and does not require the installation and replacement of actuator cylinders and actuator motors, and is highly operable; in the present invention, the inlet and return oil flow and pressure of the boom-link, dipper-link, and bucket-link are independently loaded and are not limited by the area ratio of the two chambers of the oil cylinder.

Description

Technical Field

[0001] The present invention relates to the field of hydraulic drive, and in particular to a hydraulic loading system for a semi-physical simulation platform of an excavator, which is used for simulating loading of a hydraulic system on an excavator weighing less than 70 tons. Background Art

[0002] Excavator system matching is an important research topic in the development process of the entire machine. Traditional test bench testing does not have the real-time simulation function of the excavation load. In order to make up for the shortcomings of traditional excavator system matching test benches, the verification test of the entire machine system performance must be completed in the early stage of new machine model design. Currently, this is mainly achieved by building an excavator semi-physical simulation platform.

[0003] Semi-physical simulation, also known as hardware-in-the-loop (HIL) simulation or hardware-in-the-loop (HIL), involves integrating physical hardware into the simulation system's simulation loop to replace the real-time simulation of the mathematical model. The hardware used in the semi-physical simulation platform for excavator systems primarily includes the original vehicle's power unit, multi-way valve, and operating handle. To load the valve ports, some semi-physical platforms also incorporate cylinders and motor actuators specific to the vehicle model. However, this loading method has the disadvantage of requiring the corresponding cylinders and motors to be replaced simultaneously when testing excavator systems of different tonnages, resulting in poor system adaptability.

[0004] In a loading system without cylinders or motor actuators, the load pressure at the outlet of each multi-way valve is mainly simulated through the relief valve, and the outlet flow of the relief valve is returned to the oil through the return oil port of each multi-way valve. However, during the actual vehicle operation of the excavator's multi-way valve boom, stick, and bucket joints, due to the area difference between the two chambers of the cylinder, the flow of the oil outlet and return port of each joint should be consistent with the area ratio of the two chambers of the cylinder. The above loading method can only ensure that the outlet flow and pressure of the multi-way valve are consistent with the simulation, and the return oil port flow and back pressure cannot be realistically simulated.

[0005] The flow output range of the existing semi-physical simulation loading system is limited and can only support fixed-tonnage excavator systems with similar simulated flow rates.

[0006] At present, the loading system of the rotary coupling only considers the rotary load pressure loading, and cannot realize the pressure shock simulation and return oil volume control during the rotary start. Summary of the Invention

[0007] In view of the shortcomings of the existing technology, the present invention proposes a hydraulic loading system for a semi-physical simulation platform of an excavator. The system has strong versatility and the oil ports on both sides can be loaded independently.

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

[0009] A hydraulic loading system for an excavator semi-physical simulation platform includes a loading pump group, a confluence switching valve group, a boom loading valve group, an arm loading valve group, a bucket loading valve group, a swing loading valve group, a flow detection component, a pressure detection component, a multi-way valve, and an excavator power unit;

[0010] The loading pump group includes seven groups of electronically controlled variable displacement plunger pumps and one group of pilot gear pumps; the electronically controlled variable displacement plunger pumps change the pump flow rate by adjusting the proportional valve on the pump. The outlets of the electronically controlled variable displacement plunger pumps are all connected to a one-way valve to prevent the oil from flowing back into the pump. The pilot gear pump is used to provide the pilot pressure oil required by the electronically controlled variable displacement plunger pumps;

[0011] The confluence switching valve group includes six groups of plug-in electric control stop valves, which are used to connect or cut off the two adjacent pump outlets in the loading pump group;

[0012] The boom-link loading valve group is installed between the confluence switching valve group and the flow detection assembly, and includes three sets of proportional relief valves, one set of proportional speed control valves, one set of solenoid reversing valves, and two sets of check valves, which are used to control the bypass pressure of the boom-link speed control circuit and the loading pressure and flow of the A1 and B1 ports corresponding to the boom-link of the multi-way valve;

[0013] The arm-link loading valve group also includes three sets of proportional relief valves, one set of proportional speed control valves, one set of solenoid reversing valves, and two sets of one-way valves, which are used to control the bypass pressure of the arm-link speed control circuit and the loading pressure and flow of the A2 and B3 ports corresponding to the arm link of the multi-way valve;

[0014] The bucket link loading valve group also includes three sets of proportional relief valves, one set of proportional speed control valves, one set of solenoid reversing valves, and two sets of one-way valves, which are used to control the bypass pressure of the bucket link speed control circuit and the loading pressure and flow of the A3 and B4 ports corresponding to the bucket link of the multi-way valve;

[0015] The rotary coupling loading valve group includes two sets of proportional relief valves, one set of proportional speed regulating valves and one set of one-way valves, which are used to control the bypass pressure of the rotary coupling and the loading pressure and flow of the A4 and B3 ports corresponding to the rotary coupling of the multi-way valve;

[0016] The flow detection assembly includes seven sets of flow meters, which are respectively used to detect the flow of ports A1 and B1 corresponding to the boom connection of the multi-way valve, ports A2 and B2 corresponding to the arm connection of the multi-way valve, ports A3 and B3 corresponding to the bucket connection of the multi-way valve, and the flow of the oil return port of the rotary connection;

[0017] The pressure detection component includes eight groups of pressure sensors, which are used to detect the pressure of the A1 and B1 ports corresponding to the boom connection of the multi-way valve, the A2 and B2 ports corresponding to the arm connection of the multi-way valve, the A3 and B3 ports corresponding to the bucket connection of the multi-way valve, and the A4 and B4 ports corresponding to the rotary connection of the multi-way valve.

[0018] Furthermore, the multi-way valve is a multi-way valve for an excavator, and the excavator power unit includes a serially connected plunger pump and an engine.

[0019] Furthermore, the loading pump group includes a first electrically controlled variable displacement plunger pump, a second electrically controlled variable displacement plunger pump, a third electrically controlled variable displacement plunger pump, a fourth electrically controlled variable displacement plunger pump, a fifth electrically controlled variable displacement plunger pump, a sixth electrically controlled variable displacement plunger pump, and a seventh electrically controlled variable displacement plunger pump connected in parallel, and a pilot gear pump for providing pilot pressure oil to the seven groups of electrically controlled variable displacement plunger pumps;

[0020] The electrically controlled stop valve 1 of the confluence switching valve group is installed between the outlets of the electrically controlled variable displacement plunger pump 1 and the electrically controlled variable displacement plunger pump 2, the electrically controlled stop valve 2 is installed between the outlets of the electrically controlled variable displacement plunger pump 2 and the electrically controlled variable displacement plunger pump 3, and so on, the electrically controlled stop valve 6 is installed between the outlets of the electrically controlled variable displacement plunger pump 6 and the electrically controlled variable displacement plunger pump 7;

[0021] The confluence switching valve group has three outlets, outlet one is connected to the outlet of the electronically controlled variable displacement plunger pump one, outlet two is connected to the outlet of the electronically controlled variable displacement plunger pump four, and outlet three is connected to the outlet of the electronically controlled variable displacement plunger pump seven.

[0022] Furthermore, the boom-linked loading valve group includes a proportional relief valve 1, a proportional speed regulating valve 1, an electromagnetic reversing valve, a proportional relief valve 2, a proportional relief valve 3, a check valve 1 and a check valve 2;

[0023] The boom-linked loading valve group includes three ports, the first port of the boom-linked loading valve group is connected to the outlet 1 of the converging switching valve group; the proportional relief valve 1 is a bypass proportional relief valve, the inlet of the proportional relief valve 1 is connected to the first port of the boom-linked loading valve group and the inlet of the proportional speed control valve 1, to form a speed control circuit; the outlet of the proportional speed control valve 1 is connected to the inlet of the electromagnetic reversing valve, and the electromagnetic reversing valve is used to switch the return oil to the A1 port or B1 port of the boom-linked. The two outlets of the electromagnetic reversing valve are respectively connected to the oil outlets of the proportional relief valve 2 and the proportional relief valve 3 and the forward oil ports of the one-way valve 1 and the one-way valve 2. The inlet of the proportional relief valve 2 is connected to the reverse oil port of the one-way valve 1 and the flowmeter 1 of the flow detection assembly. The inlet of the proportional relief valve 3 is connected to the reverse oil port of the one-way valve 2 and the flowmeter 2 of the flow detection assembly. The proportional relief valve 2 and the proportional relief valve 3 are used to simulate the loading load pressure when oil is discharged from the A1 port or the B1 port.

[0024] Furthermore, one end of the arm-linked loading valve group is connected to the outlet 2 of the merging switching valve group, and one end is connected to the flow detection component; one end of the bucket-linked loading valve group is connected to the outlet 3 of the merging switching valve group, and one end is connected to the flow detection component;

[0025] The composition and internal connection mode of the arm-linked loading valve group and the bucket-linked loading valve group are the same as those of the boom-linked loading valve group.

[0026] Furthermore, the rotary loading valve group includes a proportional relief valve four, a proportional speed regulating valve two, a proportional relief valve five and a one-way valve group;

[0027] The one-way valve group includes four one-way valves, which are formed by connecting the forward oil ports and reverse oil ports of the four one-way valves in sequence, with a total of four ports C, D, E, and F; port C of the one-way valve group is connected to port A4 of the rotary joint of the multi-way valve, port D is connected to the outlet of flowmeter 7 of the flow detection assembly, port E is connected to port B4 of the rotary joint of the multi-way valve, and port F is connected to the inlet of the proportional relief valve 4 and the inlet of the proportional speed control valve 2; the outlet of the proportional speed control valve 2 is connected to the inlet of the proportional relief valve 5, and the outlet of the proportional relief valve 5 is connected to the inlet of the flowmeter 7;

[0028] The proportional relief valve four is a bypass proportional relief valve used to simulate the relief pressure during the rotation start-up; the proportional relief valve five simulates the rotation load pressure, and the proportional speed control valve two is used to control the return oil volume of the rotary link of the multi-way valve.

[0029] Furthermore, the oil inlets P1 and P2 of the multi-way valve are respectively connected to the outlets of two plunger pumps in the excavator power unit.

[0030] The beneficial effects of the present invention are as follows:

[0031] 1. The present invention adopts multiple pump groups for loading, with a wide range of loading flow, and can adapt to the semi-physical simulation platform of various excavators below 70 tons, with strong versatility.

[0032] 2. The present invention does not require installation or replacement of the execution cylinder and the execution motor, and has strong operability.

[0033] 3. In the present invention, the oil inlet and return flow rates and pressures of the boom connection, the arm connection, and the bucket connection are independently loaded and are not limited by the area ratio of the two chambers of the oil cylinder.

[0034] 4. The rotary coupling in the present invention can simulate the rotary impact condition when the rotary action is started. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of the principle of the hydraulic loading system of the present invention.

[0036] Figure 2 It is an exploded schematic diagram of the loading pump group 1 and the confluence switching valve group 2 of the present invention.

[0037] Figure 3 It is a schematic diagram of the loading principle of the boom coupling circuit of the present invention.

[0038] Figure 4 It is a schematic diagram of the loading principle of the rotary coupling circuit of the present invention.

[0039] In the figure, 1 is the loading pump group, 2 is the converging switching valve group, 3 is the boom-connected loading valve group, 4 is the arm-connected loading valve group, 5 is the bucket-connected loading valve group, 6 is the rotary-connected loading valve group, 7 is the flow detection component, 8 is the pressure detection component, 9 is the multi-way valve, and 10 is the excavator power unit. 1.1 is the first electric control variable displacement plunger pump, 1.2 is the second electric control variable displacement plunger pump, 1.3 is the third electric control variable displacement plunger pump, 1.4 is the fourth electric control variable displacement plunger pump, 1.5 is the fifth electric control variable displacement plunger pump, 1.6 is the sixth electric control variable displacement plunger pump, 1.7 is the seventh electric control variable displacement plunger pump, 1.8 is the pilot gear pump, 2.1 is the first electric control stop valve, 2.2 is the second electric control stop valve, 2.3 is the third electric control stop valve, 2.4 is the fourth electric control stop valve, 2.5 is the fifth electric control stop valve, 2.6 is the sixth electric control stop valve, 3.1 is the ratio For example, overflow valve one, 3.2 is proportional speed control valve one, 3.3 is solenoid reversing valve, 3.4 is proportional overflow valve two, 3.5 is check valve one, 3.6 is proportional overflow valve three, 3.7 is check valve two, 6.1 is proportional overflow valve four, 6.2 is proportional speed control valve two, 6.3 is proportional overflow valve five, 6.4 is check valve group, 7.1 is flow meter one, 7.2 is flow meter two, 7.7 is flow meter seven, 8.1 is pressure sensor one, 8.2 is pressure sensor two, 8.7 is pressure sensor seven, and 8.8 is pressure sensor eight. DETAILED DESCRIPTION

[0040] The present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments, and the purpose and effects of the present invention will become more apparent. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0041] like Figure 1 As shown, it mainly includes a dual-loading pump group 1, a confluence switching valve group 2, a boom-linked loading valve group 3, a dipper-linked loading valve group 4, a bucket-linked loading valve group 5, a rotary-linked loading valve group 6, a flow detection component 7, a pressure detection component 8, a multi-way valve 9 and an excavator power unit 10.

[0042] like Figure 2As shown, loading pump group 1 includes parallel-connected electronically controlled variable displacement piston pumps 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, and 1.7. It also includes a pilot gear pump 1.8, which provides pilot pressure oil for each of the seven electronically controlled variable displacement piston pumps. The displacement of electronically controlled variable displacement piston pump 1.4 is 355cc / r, while the remaining electronically controlled variable displacement piston pumps have a displacement of 250cc / r. These seven electronically controlled variable displacement piston pumps can be combined via a combining switching valve group 2, achieving a maximum combined flow rate of 2700 L / min. This allows for semi-physical simulation platform loading tests on excavators under 70 tons. Pilot gear pump 1.8 provides the required pilot pressure.

[0043] The confluence switching valve group 2 consists of six sets of plug-in electronically controlled stop valves 2.1-2.6. Each set of electronically controlled stop valves is installed between two adjacent pump outlets and is normally open. In confluence switching valve group 2, electronically controlled stop valve 1 (2.1) is installed between the outlets of electronically controlled variable displacement piston pump 1 (1.1) and electronically controlled variable displacement piston pump 2 (1.2). Electronically controlled stop valve 2 (2.2) is installed between the outlets of electronically controlled variable displacement piston pump 2 (1.2) and electronically controlled variable displacement piston pump 3 (1.3). Similarly, electronically controlled stop valve 6 (2.6) is installed between the outlets of electronically controlled variable displacement piston pump 6 (1.6) and electronically controlled variable displacement piston pump 7 (1.7). Confluence switching valve group 2 has three outlets: outlet 1 is connected to the outlet of electronically controlled variable displacement piston pump 1 (1.1), outlet 2 is connected to the outlet of electronically controlled variable displacement piston pump 4 (1.4), and outlet 3 is connected to the outlet of electronically controlled variable displacement piston pump 7 (1.7). The rated flow of plug-in electric control stop valve 2.1-2.6 is greater than 3000L / min, and each group of stop valves can be individually controlled on and off by electric control.

[0044] like Figure 3As shown, the boom loading valve group 3 includes a proportional relief valve 3.1, a proportional speed regulating valve 3.2, an electromagnetic reversing valve 3.3, a proportional relief valve 3.4, a proportional relief valve 3.6, a check valve 3.5 and a check valve 3.7. The proportional relief valve 3.1 is a bypass proportional relief valve. The boom loading valve group 3 includes three ports, wherein port 1 of the boom loading valve group 3 is connected to outlet 1 of the confluence switching valve, the inlet of the proportional relief valve 3.1 is connected to port 1 of the boom loading valve group 3 and the inlet of the proportional speed regulating valve 3.2 to form a speed regulating circuit; the outlet of the proportional speed regulating valve 3.2 is connected to the inlet of the electromagnetic reversing valve 3.3 (i.e., port P), and the electromagnetic reversing valve 3.3 is used to switch the return oil to port A1 or port B1 of the boom. The two outlets of the electromagnetic reversing valve 3.3 The ports are respectively connected to the oil outlets of proportional relief valve 2 3.4 and proportional relief valve 3.6 and the forward oil ports of check valve 1 3.5 and check valve 2 3.7. The inlet of proportional relief valve 2 3.4 is connected to the reverse oil port of check valve 1 3.5 and flow meter 1 7.1. The inlet of proportional relief valve 3.6 is connected to the reverse oil port of check valve 2 3.7 and flow meter 2 7.2. Proportional relief valve 2 3.4 and proportional relief valve 3 3.6 are used to simulate load pressure when oil is discharged from port A1 or B1.

[0045] like Figure 1 As shown, the arm-linked loading valve assembly 4 has one end connected to outlet ② of the merging switching valve assembly 2 and one end connected to the flow detection assembly 7. The bucket-linked loading valve assembly 5 has one end connected to outlet ③ of the merging switching valve assembly 2 and one end connected to the flow detection assembly 7. The composition and internal connections of the arm-linked loading valve assembly 4 and the bucket-linked loading valve assembly 5 are identical to those of the boom-linked loading valve assembly 3. The two proportional relief valves in the arm-linked loading valve assembly 4 simulate load pressure when oil is flowing out of port A2 or B2; the two proportional relief valves in the bucket-linked loading valve assembly 5 simulate load pressure when oil is flowing out of port A3 or B3.

[0046] like Figure 4As shown, the rotary loading valve assembly 3 includes a proportional relief valve 6.1 (fourth), a proportional speed control valve 6.2 (second), a proportional relief valve 6.3 (fifth), and a check valve assembly 6.4. Check valve assembly 6.4 comprises four check valves, connected in sequence, with the forward oil port of one check valve connected to the reverse oil port of another. There are four ports, C, D, E, and F. Port C of check valve assembly 6.4 is connected to port A4 of the multi-way valve rotary assembly, port D to the outlet of flowmeter 7.7, port E to port B4 of the multi-way valve rotary assembly, and port F to the inlet of bypass proportional relief valve 6.1 (fourth) and the inlet of proportional speed control valve 6.2 (second). The outlet of proportional speed control valve 6.2 is connected to the inlet of proportional relief valve 6.3 (fifth), and the outlet of proportional relief valve 6.3 is connected to the inlet of flowmeter 7.7. Proportional relief valve 4 (6.1) is a bypass proportional relief valve used to simulate the relief pressure during swing start-up. Its outlet is connected to the oil tank. Proportional relief valve 5 (6.3) simulates the swing load pressure. Proportional speed control valve 2 (6.2) controls the return oil volume from the swing link of multi-way valve 9.

[0047] The flow detection assembly 7 includes seven sets of flow meters, of which flow meter 1 7.1 and flow meter 2 7.2 are used to detect the flow at ports A1 and B1 of the boom link of the feedback multi-way valve; flow meters 3 to 6 are used to detect the flow at ports A2 and B2 of the dipper link and ports A3 and B3 of the bucket link respectively; and flow meter 7.7 is used to detect the flow at the return oil port of the swing link.

[0048] The pressure detection assembly 8 includes 8 pressure sensors, pressure sensor 1 8.1 is installed at the A1 port of the boom connection of the multi-way valve, pressure sensor 2 8.2 is installed at the B1 port of the boom connection of the multi-way valve, pressure sensors 3 to 6 are respectively installed at the A2 port and B2 port of the dipper arm connection of the multi-way valve, and the A3 port and B3 port of the bucket connection of the multi-way valve, pressure sensor 7 8.7 is installed at the A4 port of the rotary connection of the multi-way valve, and pressure sensor 8 8.8 is installed at the B4 port of the rotary connection of the multi-way valve, which are used to detect and feedback the pressure of each port of the multi-way valve.

[0049] The multi-way valve 9 and the excavator power unit 10 are both tested parts on the semi-physical simulation platform, and are consistent with the actual parts used in the excavator systems of various tonnages.

[0050] The oil inlets P1 and P2 of multi-way valve 9 are connected to the outlets of the two plunger pumps in the excavator power unit 10, respectively, providing oil. The return oil flow from the boom, arm, and bucket connections is supplied by the dual loading pump group 1. The loading valve group simulates the load pressure, and the speed regulating valves of each loading valve group control the return oil volume and return oil back pressure. The swing connection uses the swing loading valve group to control the return oil volume and simulate the swing load.

[0051] The present invention can realize the simulated loading function of each single action and compound action. During the compound action test, the converging switching valve group 2 is used to distribute the flow of each link.

[0052] When simulating the hydraulic loading of a small-tonnage excavator, the present invention can reduce the system overflow and heat generation by controlling the number of activated plunger pumps of the loading pump group and coordinating the electronic control to adjust the displacement.

[0053] In the present invention, each control valve, multi-way valve and pump return oil (oil suction) all lead to the same oil tank.

[0054] The hydraulic loading system of the present invention can realize single-action loading of a multi-way valve and multi-action compound loading.

[0055] like Figure 2 As shown, the converging switching valve group 2 distributes the oil return flow to the boom, arm, and bucket units. During single-action operation of the boom unit, if the boom unit's oil return flow demand is less than 350 L / min, all electronically controlled shutoff valves 2.1-2.7 on the converging switching valve group 2 are energized and closed. Electronically controlled variable-displacement plunger pump 1.1 on loading pump group 1 is activated, while the remaining pumps are deactivated. Electronically controlled variable-displacement plunger pump 1.1 supplies oil to the boom unit. When the boom unit's oil return flow demand is greater than 350 L / min but less than 700 L / min, electronically controlled shutoff valve 2.1 loses power, the remaining electronic shutoff valves are energized and closed, and electronically controlled variable-displacement plunger pump 1.1 and electronically controlled variable-displacement plunger pump 2 1.2 are activated. The remaining pumps are deactivated, and the combined flow of these two pumps supplies oil to the boom unit. When the boom oil return port flow rate demand is greater than 700L / min but less than 1050L / min, the electronically controlled stop valves 1-2.1 and 2-2 are de-energized, the remaining electronically controlled stop valves are energized and closed, and the electronically controlled variable displacement plunger pumps 1-1.1, 2-1.2, and 3-1.3 are activated. The remaining pumps are shut down, and the three pumps combine to supply oil to the boom oil return port. When the boom oil return port flow rate demand is greater than 1050L / min but less than 1550L / min, the electronically controlled stop valves 1-2.1, 2-2.2, and 3-2.3 are de-energized, the remaining electronically controlled stop valves are energized and closed, and the electronically controlled variable displacement plunger pumps 1-1.1, 2-1.2, 3-1.3, and 4-1.4 are activated. The remaining pumps are shut down, and the four pumps combine to supply oil to the boom oil return port. As shown in Table 1, the maximum return oil flow required by the boom linkage is 1450 L / min. Therefore, a maximum of four pumps can meet the boom linkage's single action requirements. During boom linkage single action, the proportional speed control valves on arm linkage loading valve group 4 and bucket linkage loading valve group 5 are closed, and the bypass proportional relief valve is set to maximum pressure.

[0056] Table 1 Statistics of the maximum flow rates of the large and small chambers of the cylinders of a 65-ton excavator under various movements

[0057]

[0058] When the arm linkage is operating alone and the flow demand at the arm linkage's oil return port is less than 500 L / min, the electrically controlled shutoff valves 1-7 (2.1-2.7) on the converging switching valve group 2 are all energized and closed. The electrically controlled variable-displacement plunger pump 4 (1.4) on the loading pump group 1 is opened, while the remaining pumps are shut off. The electrically controlled variable-displacement plunger pump 4 (1.4) supplies oil to the arm linkage. When the flow demand at the arm linkage's oil return port is greater than 500 L / min but less than 860 L / min, the electrically controlled shutoff valve 3 (2.3) loses power, the remaining electrically controlled shutoff valves are energized and closed, and the electrically controlled variable-displacement plunger pumps 3 (1.3) and 4 (1.4) are opened. The remaining pumps are shut off, and the combined flow of the two pumps supplies oil to the arm linkage. When the arm-link oil return port flow rate demand is greater than 860L / min but less than 1220L / min, the electronically controlled stop valves 2.2 and 3.3 lose power and conduct, the remaining electronically controlled stop valves are energized and closed, the electronically controlled variable-displacement plunger pumps 2.2, 3.3, and 4.4 are activated, the remaining pumps are shut off, and the three pumps combine to supply oil to the arm-link. When the arm-link oil return port flow rate demand is greater than 1220L / min but less than 1550L / min, the electronically controlled stop valves 1.1, 2.2, and 3.3 lose power and conduct, the remaining electronically controlled stop valves are energized and closed, the electronically controlled variable-displacement plunger pumps 1.1, 2.2, 3.3, and 4.4 are activated, the remaining pumps are shut off, and the four pumps combine to supply oil to the boom-link. When the arm-link oil return port flow rate demand is greater than 1550L / min but less than 1910L / min, electronically controlled stop valves 1-2.1, 2-2, 3-2.3, and 4-2.4 lose power and conduct, the remaining electronically controlled stop valves are energized and closed, electronically controlled variable-displacement plunger pumps 1-1.1, 2-1.2, 3-1.3, 4-1.4, and 5-1.5 are activated, the remaining pumps are shut off, and pump five combines to supply oil to the arm-link. When the arm-link oil return port flow rate demand is greater than 1910L / min but less than 2270L / min, electronically controlled stop valve 6-2.6 is energized and closed, the remaining electronically controlled stop valves lose power and conduct, electronically controlled variable-displacement plunger pump 7-1.7 is shut off, the remaining pumps are turned on, and pump six combines to supply oil to the arm-link. When the arm link's return oil flow rate demand is greater than 2270 L / min but less than 2630 L / min, all electronically controlled shutoff valves are de-energized, all pump groups are activated, and the seven pumps combine to supply oil to the arm link. As shown in Table 1, the boom link's maximum return oil flow demand is 2280 L / min, so the combined flow of the seven pumps can meet the boom link's single motion requirements. During the arm link's single motion, the proportional speed control valves on the boom link's loading valve group 3 and the bucket link's loading valve group 5 are both closed, and the bypass proportional relief valve is set to maximum pressure.

[0059] When the bucket linkage is operating alone, if the flow demand at the bucket linkage's oil return port is less than 350 L / min, the electrically controlled shutoff valves 1 to 7 (2.1-2.7) on the converging switching valve group 2 are all energized and closed, electrically controlled variable-displacement plunger pump 7 (1.7) on the loading pump group 1 is activated, and the remaining pumps are deactivated. Oil is then supplied to the bucket linkage by electrically controlled variable-displacement plunger pump 7 (1.7). When the flow demand at the bucket linkage's oil return port is greater than 350 L / min but less than 700 L / min, electrically controlled shutoff valve 6 (2.6) loses power, the remaining electrically controlled shutoff valves are energized and closed, electrically controlled variable-displacement plunger pumps 6 (1.6) and 7 (1.7) are activated, and the remaining pumps are deactivated. The two pumps then combine to supply oil to the bucket linkage. When the bucket chain's oil return port flow rate is greater than 700 L / min but less than 1050 L / min, the electronically controlled shutoff valves 52.5 and 62.6 are de-energized, the remaining electronically controlled shutoff valves are energized and closed, and the electronically controlled variable-displacement plunger pumps 51.5, 61.6, and 71.7 are activated. The remaining pumps are shut off, and the three pumps combine to supply oil to the bucket chain. When the bucket chain's oil return port flow rate is greater than 1050 L / min but less than 1550 L / min, the electronically controlled shutoff valves 42.4, 52.5, and 62.6 are de-energized, the remaining electronically controlled shutoff valves are energized and closed, and the electronically controlled variable-displacement plunger pumps 41.4, 51.5, 61.6, and 71.7 are activated. The remaining pumps are shut off, and the four pumps combine to supply oil to the bucket chain. As shown in Table 1, the bucket chain's maximum return oil demand is 1450 L / min, so a maximum of four pumps can combine to meet the bucket chain's single action requirements. When the bucket is in single motion, the proportional speed regulating valves on the boom loading valve group 3 and the arm loading valve group 4 are closed, and the bypass proportional relief valve is set to the maximum pressure.

[0060] As shown in Table 1, when simulating the combined action of boom raising and arm extending, the return oil of the boom link and the arm link are both small-chamber return oil volumes, all electronically controlled stop valves are electrically closed, and the electronically controlled variable displacement plunger pump 1.1 supplies oil to the boom link. The maximum return oil volume requirement of the boom link is 200L / min, which can be met by a single pump. The electronically controlled variable displacement plunger pump 4 1.4 supplies oil to the arm link. The maximum return oil volume requirement of the arm link is 470L / min, which can be met by a single pump.

[0061] When simulating the combined action of boom lowering and stick retracting, the return oil of the boom link and stick link are both large-cavity return oil volumes, and the electronically controlled stop valves 3 2.3 and 6 2.6 are energized to close. When the boom link return oil demand is less than 350L / min, the electronically controlled stop valves 1 2.1 and 2 2.2 are energized to close, and the electronically controlled variable displacement plunger pump 1.1 supplies oil to the boom link. When the boom link return oil port flow demand is greater than 350L / min but less than 700L / min, the electronically controlled stop valve 1 2.1 loses power and conducts, and the electronically controlled stop valve 2 2.2 It is powered on and closed, and the electric-controlled variable-displacement plunger pump 1.1 and the electric-controlled variable-displacement plunger pump 1.2 combine to supply oil to the boom joint. When the flow demand of the boom joint's oil return port is greater than 700L / min and less than 1050L / min, the electric-controlled stop valves 2.1 and 2.2 lose power and are turned on, and the electric-controlled variable-displacement plunger pumps 1.1, 1.2 and 1.3 combine to supply oil to the boom joint. The maximum return oil demand of the boom joint is 890L / min, and the combination of up to three pumps can meet the boom joint's oil return demand. When the flow demand of the boom link oil return port is less than 500L / min, the electronically controlled stop valves 42.4 and 52.5 are energized and closed, and the electronically controlled variable displacement plunger pump 41.4 supplies oil to the boom link. When the flow demand of the boom link oil return port is greater than 500L / min but less than 860L / min, the electronically controlled stop valve 42.4 is de-energized and connected, the electronically controlled stop valve 52.5 is energized and closed, and the electronically controlled variable displacement plunger pumps 41.4 and 51.5 are combined to supply oil to the boom link. When the flow demand of the boom link oil return port is greater than 860L / min but less than 1220L / min, the electronically controlled stop valves 42.4 and 52.5 are de-energized and connected, and the electronically controlled variable displacement plunger pumps 41.4, 51.5 and 61.6 are combined to supply oil to the boom link. The maximum return oil demand of the boom link is 1220L / min, and the confluence of up to three pumps can meet the boom link oil return demand.

[0062] When simulating the compound action of arm extension and bucket digging, the return oil of the arm link and the bucket link are both small-cavity return oil volumes, all electronically controlled stop valves are electrically closed, and the electronically controlled variable displacement plunger pump 4 1.4 supplies oil to the arm link. The maximum return oil volume requirement of the arm link is 490L / min, which can be met by a single pump. The electronically controlled variable displacement plunger pump 7 1.7 supplies oil to the bucket link. The maximum return oil volume requirement of the bucket link is 230L / min, which can be met by a single pump.

[0063] When simulating the combined action of boom lifting, arm extension and bucket digging, the return oil of the boom link, arm link and bucket link are all small-cavity return oil volumes, and all electronically controlled stop valves are electrically closed. The electronically controlled variable displacement plunger pump 1.1 supplies oil to the boom link, and the maximum return oil volume demand of the boom link is 160L / min, which can be met by a single pump. The electronically controlled variable displacement plunger pump 4 1.4 supplies oil to the arm link, and the maximum return oil volume demand of the arm link is 450L / min, which can be met by a single pump. The electronically controlled variable displacement plunger pump 7 1.7 supplies oil to the bucket link, and the maximum return oil volume demand of the bucket link is 120L / min, which can be met by a single pump.

[0064] When simulating the combined action of boom raising, arm retracting and bucket opening, the boom link returns oil to a small cavity, while the arm link and bucket link return oil to a large cavity. The electrically controlled stop valves 1-2.1 and 4-2.4 are energized and closed, and the electrically controlled variable displacement plunger pump 1-1.1 supplies oil to the boom link. The maximum oil return volume requirement of the boom link is 180L / min, which can be met by a single pump. When the flow demand of the boom link oil return port is less than 500L / min, the electronically controlled stop valves 2.2 and 2.3 are energized and closed, and the electronically controlled variable displacement plunger pump 4 1.4 supplies oil to the boom link. When the flow demand of the boom link oil return port is greater than 500L / min but less than 860L / min, the electronically controlled stop valve 3 2.3 is de-energized and connected, the electronically controlled stop valve 2.2 is energized and closed, and the electronically controlled variable displacement plunger pumps 3 1.3 and 4 1.4 are combined to supply oil to the boom link. When the flow demand of the boom link oil return port is greater than 860L / min but less than 1220L / min, the electronically controlled stop valves 2.2 and 2.3 are de-energized and connected, and the electronically controlled variable displacement plunger pumps 2 1.2, 3 1.3 and 4 1.4 are combined to supply oil to the boom link. The maximum return oil demand of the boom link is 1100L / min, and the confluence of up to three pumps can meet the boom link oil return demand. When the bucket joint oil return demand is less than 350L / min, the electronically controlled stop valves 52.5 and 62.6 are energized and closed, and the electronically controlled variable displacement plunger pump 71.7 supplies oil to the bucket joint. When the bucket joint oil return port flow demand is greater than 350L / min but less than 700L / min, the electronically controlled stop valve 62.6 is de-energized and connected, the electronically controlled stop valve 52.5 is energized and closed, and the electronically controlled variable displacement plunger pumps 61.6 and 71.7 are combined to supply oil to the bucket joint. When the bucket joint oil return port flow demand is greater than 700L / min but less than 1050L / min, the electronically controlled stop valves 52.5 and 62.6 are de-energized and connected, and the electronically controlled variable displacement plunger pumps 51.5, 61.6 and 71.7 are combined to supply oil to the bucket joint. The maximum bucket joint oil return demand is 870L / min, and the combination of up to three pumps can meet the bucket joint oil return demand.

[0065] like Figure 3As shown, when the boom linkage simulates the boom lifting condition, the electromagnetic reversing valve 3.3 is energized and switched to the left position. The boom linkage oil is provided by the excavator power unit through the multi-way valve P1 and P2 ports. The A1 port oil outlet circuit simulates the large cavity circuit of the excavator boom cylinder. The A1 port oil flows into the oil tank through the flow meter 7.1, the proportional relief valve 3.4, and the electromagnetic reversing valve 3.3. The pressure closed loop control is performed according to the load pressure issued by the simulation platform and the feedback pressure of the pressure sensor 8.1. The current of the proportional relief valve 3.4 is adjusted in real time. The flow meter 7.1 feeds back the A1 port circuit flow to the simulation platform. The B1 port The oil return circuit simulates the small-cavity circuit of the excavator boom cylinder. The oil output from the loading pump group flows into port B1 through the converging switching valve group 2, the proportional speed control valve 1 3.2, the solenoid reversing valve 3.3, the one-way valve 2 3.7, and the flow meter 2 7.2. The flow closed-loop control is performed based on the return oil flow issued by the simulation platform and the feedback flow from the flow meter 2 7.2. The pressure sensor 2 8.2 feeds back the return oil back pressure of port B1 to the simulation platform. The set pressure of the proportional relief valve 1 3.1 (the proportional relief valve of the bypass) is more than 1 MPa higher than the return oil back pressure to ensure that the inlet and outlet pressure difference of the proportional speed control valve 1 3.2 is above the minimum working pressure difference.

[0066] When the boom linkage simulates the boom lowering condition, the electromagnetic reversing valve 3.3 loses power and remains in the right position. The oil outlet circuit of port B1 simulates the small cavity circuit of the excavator boom cylinder. The oil outlet of port B1 flows into the oil tank through flow meter 2 7.2, proportional relief valve 3 3.6, and electromagnetic reversing valve 3.3. The pressure closed loop control is performed according to the load pressure issued by the simulation platform and the feedback pressure of pressure sensor 2 8.2. The current of proportional relief valve 3 3.6 is adjusted in real time. The flow meter 2 7.2 feeds back the flow of the B1 circuit to the simulation platform. The return oil circuit of port A1 simulates the large cavity circuit of the excavator boom cylinder. In the cavity circuit, the oil output from the loading pump group 1 flows into the A1 port through the converging switching valve group 2, the proportional speed control valve 3.2, the electromagnetic reversing valve 3.3, the one-way valve 3.5, and the flow meter 7.1. The flow closed-loop control is performed according to the return oil flow issued by the simulation platform and the feedback flow from the flow meter 7.1. The pressure sensor 8.1 feeds back the return oil back pressure of the A1 port to the simulation platform. The set pressure of the proportional relief valve 3.1 (bypass proportional relief valve) is more than 1 MPa higher than the return oil back pressure to ensure that the inlet and outlet pressure difference of the proportional speed control valve 3.2 is higher than the minimum working pressure difference.

[0067] When the arm link simulates the arm extension working condition and the bucket link simulates the bucket digging working condition, the control method of the arm link loading valve group 4 and the bucket link loading valve group 5 is the same as the control method of the boom link simulating the rising working condition.

[0068] When the boom linkage simulates the boom retracted working condition and the bucket linkage simulates the bucket open working condition, the control method of the boom linkage loading valve group 4 and the bucket linkage loading valve group 5 is the same as the control method of the boom linkage simulating the descending working condition.

[0069] like Figure 4As shown, the swing link oil inlet is provided by the excavator power unit through ports P1 and P2 of the multi-way valve. When simulating forward swing, the oil outlet circuit at port A4 simulates the inlet circuit of the excavator hydraulic motor. The oil outlet at port A4 flows through ports C and F on the check valve assembly 6.4, proportional speed control valve 2 6.2, proportional relief valve 5 6.3, flowmeter 7.7, and ports D and E on the check valve assembly 6.4 to port B4 of the swing link. When simulating reverse swing, the oil outlet circuit at port B4 simulates the inlet circuit of the excavator hydraulic motor. The oil outlet at port A4 flows through ports E and F on the check valve assembly 6.4, proportional speed control valve 2 6.2, proportional relief valve 5 6.3, flowmeter 7.7, and ports D and C on the check valve assembly 6.4 to port A4 of the swing link. When simulating the starting impact, the rotary impact pressure is set by the proportional relief valve four 6.1, and the flow closed-loop control is performed through the flow meter seven 7.7. The return oil volume is adjusted to be consistent with the return oil volume issued by the simulation platform through the proportional speed control valve two 6.2. The excess flow overflows through the proportional relief valve four 6.1. During normal rotation, the rotary joint outlet flow all enters the return oil port for return oil, and the proportional relief valve four 6.1 has no overflow. The pressure closed-loop control is performed through the pressure sensor seven 8.7 (forward rotation) or the pressure sensor eight 8.8 (reverse rotation). The proportional relief valve five 6.3 is adjusted to control the oil outlet pressure to be consistent with the load pressure issued by the simulation platform.

[0070] Those skilled in the art will understand that the foregoing descriptions are merely preferred embodiments of the invention and are not intended to limit the invention. Although the invention has been described in detail with reference to the foregoing examples, those skilled in the art will still be able to modify the technical solutions described in the foregoing examples or substitute equivalents for some of the technical features therein. Any modifications, equivalent substitutions, etc. made within the spirit and principles of the invention shall be included within the scope of protection of the invention.

Claims

1. A hydraulic loading system for an excavator semi-physical simulation platform, characterized in that: It comprises a loading pump group (1), a confluence switching valve group (2), a boom-linked loading valve group (3), a dipper-arm-linked loading valve group (4), a bucket-linked loading valve group (5), a rotary-linked loading valve group (6), a flow detection component (7), a pressure detection component (8), a multi-way valve (9) and an excavator power unit (10); The loading pump group (1) includes seven groups of electronically controlled variable displacement plunger pumps and one group of pilot gear pumps (1.8); the electronically controlled variable displacement plunger pumps change pump flow by adjusting proportional valves on the pumps; outlets of the electronically controlled variable displacement plunger pumps are all connected to one-way valves to prevent oil from flowing back into the pumps; the pilot gear pumps (1.8) are used to provide pilot pressure oil required by the electronically controlled variable displacement plunger pumps; The confluence switching valve group (2) includes six groups of plug-in electric control stop valves, which are used to connect or cut off two adjacent pump outlets in the loading pump group (1); The boom-link loading valve group (3) is installed between the confluence switching valve group (2) and the flow detection assembly (7), and includes three groups of proportional relief valves, one group of proportional speed regulating valves, one group of electromagnetic reversing valves, and two groups of one-way valves, and is used to control the bypass pressure of the boom-link speed regulating circuit and the loading pressure and flow of the A1 and B1 ports corresponding to the boom-link of the multi-way valve (9); The arm-link loading valve group (4) also includes three groups of proportional relief valves, one group of proportional speed regulating valves, one group of electromagnetic reversing valves, and two groups of one-way valves, which are used to control the bypass pressure of the arm-link speed regulating circuit and the loading pressure and flow of the A2 and B2 ports corresponding to the arm-link of the multi-way valve (9); The bucket link loading valve group (5) also includes three groups of proportional relief valves, one group of proportional speed regulating valves, one group of electromagnetic reversing valves, and two groups of one-way valves, which are used to control the bypass pressure of the bucket link speed regulating circuit and the loading pressure and flow of the A3 and B3 ports corresponding to the bucket link of the multi-way valve (9); The rotary coupling loading valve group (6) includes two groups of proportional relief valves, one group of proportional speed regulating valves and one group of one-way valves, which are used to control the bypass pressure of the rotary coupling and the loading pressure and flow of the A4 and B4 ports corresponding to the rotary coupling of the multi-way valve (9); The flow detection assembly (7) includes seven groups of flow meters, which are respectively used to detect the flow of the A1 and B1 ports corresponding to the boom connection of the multi-way valve (9), the A2 and B2 ports corresponding to the arm connection of the multi-way valve (9), the A3 and B3 ports corresponding to the bucket connection of the multi-way valve (9), and the return oil port flow of the rotary connection; The pressure detection assembly (8) includes eight groups of pressure sensors, which are respectively used to detect the pressures of the A1 and B1 ports corresponding to the boom connection of the multi-way valve (9), the A2 and B2 ports corresponding to the arm connection of the multi-way valve (9), the A3 and B3 ports corresponding to the bucket connection of the multi-way valve (9), and the A4 and B4 ports corresponding to the swing connection of the multi-way valve (9).

2. The hydraulic loading system for the excavator semi-physical simulation platform according to claim 1 is characterized in that: The multi-way valve (9) is a multi-way valve for an excavator, and the excavator power unit (10) includes a serially connected plunger pump and an engine.

3. The hydraulic loading system for the excavator semi-physical simulation platform according to claim 1 is characterized in that: The loading pump group (1) comprises a first electrically controlled variable displacement plunger pump (1.1), a second electrically controlled variable displacement plunger pump (1.2), a third electrically controlled variable displacement plunger pump (1.3), a fourth electrically controlled variable displacement plunger pump (1.4), a fifth electrically controlled variable displacement plunger pump (1.5), a sixth electrically controlled variable displacement plunger pump (1.6), a seventh electrically controlled variable displacement plunger pump (1.7) connected in parallel, and a pilot gear pump (1.8) for providing pilot pressure oil to the seven groups of electrically controlled variable displacement plunger pumps; The electrically controlled stop valve 1 (2.1) of the confluence switching valve group (2) is installed between the outlets of the electrically controlled variable displacement plunger pump 1 (1.1) and the electrically controlled variable displacement plunger pump 2 (1.2), the electrically controlled stop valve 2 (2.2) is installed between the outlets of the electrically controlled variable displacement plunger pump 2 (1.2) and the electrically controlled variable displacement plunger pump 3 (1.3), and so on, the electrically controlled stop valve 6 (2.6) is installed between the outlets of the electrically controlled variable displacement plunger pump 6 (1.6) and the electrically controlled variable displacement plunger pump 7 (1.7); The confluence switching valve group (2) has three outlets in total, outlet one is connected to the outlet of the electric-controlled variable displacement plunger pump one (1.1), outlet two is connected to the outlet of the electric-controlled variable displacement plunger pump four (1.4), and outlet three is connected to the outlet of the electric-controlled variable displacement plunger pump seven (1.7).

4. The hydraulic loading system for the excavator semi-physical simulation platform according to claim 3 is characterized in that: The boom-linked loading valve group (3) comprises a proportional relief valve 1 (3.1), a proportional speed regulating valve 1 (3.2), an electromagnetic reversing valve (3.3), a proportional relief valve 2 (3.4), a proportional relief valve 3 (3.6), a check valve 1 (3.5) and a check valve 2 (3.7); The boom coupling loading valve group (3) comprises three ports, the first port of the boom coupling loading valve group (3) is connected to the outlet 1 of the converging switching valve group (2); the proportional relief valve 1 (3.1) is a bypass proportional relief valve, the inlet of the proportional relief valve 1 (3.1) is connected to the first port of the boom coupling loading valve group (3) and the inlet of the proportional speed regulating valve 1 (3.2), so as to form a speed regulating circuit; the outlet of the proportional speed regulating valve 1 (3.2) is connected to the inlet of the electromagnetic reversing valve (3.3), and the electromagnetic reversing valve (3.3) is used to switch the oil return to the A1 port or the B1 port of the boom coupling. The electromagnetic reversing valve (3.3) ) are respectively connected to the oil outlets of proportional relief valve 2 (3.4) and proportional relief valve 3 (3.6) and the forward oil ports of check valve 1 (3.5) and check valve 2 (3.7); the inlet of proportional relief valve 2 (3.4) is connected to the reverse oil port of check valve 1 (3.5) and flow meter 1 (7.1) of the flow detection assembly (7); the inlet of proportional relief valve 3 (3.6) is connected to the reverse oil port of check valve 2 (3.7) and flow meter 2 (7.2) of the flow detection assembly (7); proportional relief valve 2 (3.4) and proportional relief valve 3 (3.6) are used to simulate the load pressure when oil is discharged from port A1 or port B1.

5. The hydraulic loading system for the excavator semi-physical simulation platform according to claim 4 is characterized in that: One end of the arm-linked loading valve group (4) is connected to the second outlet of the merging switching valve group (2), and one end is connected to the flow detection component (7); one end of the bucket-linked loading valve group (5) is connected to the third outlet of the merging switching valve group (2), and one end is connected to the flow detection component (7); The composition and internal connection mode of the arm-linked loading valve group (4) and the bucket-linked loading valve group (5) are the same as those of the boom-linked loading valve group (3).

6. The hydraulic loading system for the excavator semi-physical simulation platform according to claim 4, characterized in that: The rotary loading valve group (3) includes a proportional relief valve four (6.1), a proportional speed regulating valve two (6.2), a proportional relief valve five (6.3) and a one-way valve group (6.4); The one-way valve group (6.4) includes four one-way valves, which are formed by connecting the forward oil ports and reverse oil ports of the four one-way valves in sequence, with a total of four ports C, D, E, and F; port C of the one-way valve group (6.4) is connected to port A4 of the rotary joint of the multi-way valve (9), port D is connected to the outlet of flow meter seven (7.7) of the flow detection component (7), port E is connected to port B4 of the rotary joint of the multi-way valve (9), and port F is connected to the inlet of proportional relief valve four (6.1) and the inlet of proportional speed control valve two (6.2); the outlet of proportional speed control valve two (6.2) is connected to the inlet of proportional relief valve five (6.3), and the outlet of proportional relief valve five (6.3) is connected to the inlet of flow meter seven (7.7); The proportional relief valve 4 (6.1) is a bypass proportional relief valve used to simulate the relief pressure during the swing start-up; the proportional relief valve 5 (6.3) simulates the swing load pressure; the proportional speed regulating valve 2 (6.2) is used to control the return oil volume of the swing link of the multi-way valve (9).

7. The hydraulic loading system for the excavator semi-physical simulation platform according to claim 4, characterized in that: The oil inlets P1 and P2 of the multi-way valve (9) are respectively connected to the outlets of the two plunger pumps in the excavator power unit (10).

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