Hydraulic pump control system, control method and engineering mechanical equipment

Abstract

The invention relates to the technical field of engineering machinery, and discloses a hydraulic pump control system and method and engineering mechanical equipment, and the system comprises a hydraulic oil supply unit which is used for sucking hydraulic oil from a main hydraulic oil tank or the main hydraulic oil tank and an auxiliary hydraulic oil tank, and providing working oil for an execution unit; the hydraulic oil return control unit is used for adjusting the direction of return oil of the execution unit, so that the return oil flows to the main hydraulic oil tank or the main hydraulic oil tank and the auxiliary hydraulic oil tank; the air suction prevention control unit is used for controlling hydraulic oil of the auxiliary hydraulic oil tank to enter the hydraulic oil supply unit; and the control unit is used for controlling the working states of the hydraulic oil return control unit and the air suction prevention control unit. According to the working state of the hydraulic pump, hydraulic oil of the auxiliary hydraulic oil pump can be controlled to participate in circulation of a hydraulic system, intelligent control over oil suction of the hydraulic pump is achieved on the basis of a physical structure, stable operation of the hydraulic pump under various working conditions is guaranteed, and the hydraulic pump is protected.

Description

Technical Field

[0001] The present invention relates to the technical field of engineering machinery, and in particular to a hydraulic pump control system, a control method and engineering machinery equipment. Background Art

[0002] During earthmoving or mining operations, engineering machinery can face the risk of hydraulic pump cavitation at any time due to temperature fluctuations, steep road slopes, and other working conditions. For example, in large mines, excavators frequently navigate steep slopes, especially during rapid movements. Furthermore, the mining environment is extremely harsh, and the viscosity of hydraulic oil at low temperatures can lead to poor oil absorption or cavitation. This can lead to cavitation in the hydraulic pump at best, and even wear and tear in the plunger, resulting in immediate failure and contamination of the entire hydraulic system. This can significantly delay construction and incur high maintenance costs.

[0003] In the existing technology, the solution to prevent hydraulic pumps from sucking air mainly focuses on reducing the height difference between the hydraulic pump and the hydraulic oil tank, designing a pressure compensation method in the hydraulic oil pipeline, etc. However, due to space limitations in the design of engineering machinery, it is not fully applicable. In addition, adding a pressure compensation method to the hydraulic oil will cause large pressure fluctuations, which will greatly affect the operating comfort performance. Summary of the Invention

[0004] In view of this, the present invention provides a hydraulic pump control system, a control method and an engineering machinery device to solve the problem that anti-cavitation cannot be achieved smoothly.

[0005] In the first aspect, the present invention provides a hydraulic pump control system, including: a control unit, a hydraulic oil supply unit, an execution unit, a hydraulic oil return control unit, a main hydraulic oil tank, a subsidiary hydraulic oil tank and an anti-cavitation control unit; a hydraulic oil supply unit, the input end of which is connected to the main hydraulic oil tank and the subsidiary hydraulic oil tank, and the output end is connected to the first end of the execution unit, for sucking hydraulic oil from the main hydraulic oil tank, or the main hydraulic oil tank and the subsidiary hydraulic oil tank to provide working oil for the execution unit; a hydraulic oil return control unit, connected to the second end of the execution unit, for adjusting the direction of the return oil of the execution unit so that the return oil flows to the main hydraulic oil tank, or the main hydraulic oil tank and the subsidiary hydraulic oil tank; an anti-cavitation control unit, connected to the output end of the hydraulic oil supply unit, for controlling the hydraulic oil in the subsidiary hydraulic oil tank to enter the hydraulic oil supply unit; a control unit, connected to the hydraulic oil return control unit and the anti-cavitation control unit, for controlling the working states of the hydraulic oil return control unit and the anti-cavitation control unit.

[0006] The hydraulic pump control system provided by the present invention controls the operating states of the hydraulic oil return control unit and the anti-cavitation control unit through a control unit. The anti-cavitation control unit controls the hydraulic oil in the auxiliary hydraulic oil tank to enter the hydraulic oil supply unit. The hydraulic oil return control unit adjusts the direction of the return oil from the execution unit so that the return oil enters the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, so that the hydraulic oil supply unit draws hydraulic oil from the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, to provide working oil for the execution unit. By deploying the anti-cavitation control unit, the present invention can control the hydraulic oil of the auxiliary hydraulic oil pump to participate in the circulation of the hydraulic system according to the operating state of the hydraulic pump, realize intelligent control of the hydraulic pump oil suction based on the physical structure, ensure the stable operation of the hydraulic pump under various working conditions, play a protective role for the hydraulic pump, and thus ensure the normal progress of engineering operations.

[0007] In an optional embodiment, the hydraulic oil supply unit includes: a power unit, a plunger hydraulic main pump and a pilot gear pump; the power unit is connected to the driving end of the plunger hydraulic main pump and the driving end of the pilot gear pump, and is used to provide hydraulic energy for the plunger hydraulic main pump and the pilot gear pump; the plunger hydraulic main pump, the input end of which is connected to the main hydraulic oil tank and the auxiliary hydraulic oil tank, and the output end is connected to the execution unit, and is used to suck hydraulic oil from the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, to provide working oil for the execution unit; the pilot gear pump, the input end of which is connected to the main hydraulic oil tank and the auxiliary hydraulic oil tank, and the output end is connected to the anti-cavitation control unit, and is used to suck hydraulic oil from the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, to provide pilot control oil for the anti-cavitation control unit.

[0008] The embodiment of the present invention utilizes a power unit and a plunger hydraulic main pump to provide a source of hydraulic oil for the actuator, enabling the actuator to operate normally under the influence of the hydraulic oil. Simultaneously, a pilot gear pump provides pilot control oil to the anti-cavitation control unit. This pilot oil pressure activates the control valve, connecting the return and suction lines corresponding to the auxiliary hydraulic oil tank, allowing the hydraulic oil in the auxiliary hydraulic oil tank to participate in the hydraulic circulation.

[0009] In an optional embodiment, the hydraulic oil return control unit includes: a back pressure valve and a bypass valve, the back pressure valve having a first end connected to the execution unit and a second end connected to the main hydraulic oil tank, and being used to open when the current pressure of the back pressure valve reaches a first preset pressure, so that the return oil flows to the main hydraulic oil tank; the bypass valve having a first end connected to the execution unit and a second end connected to the main hydraulic oil tank and the auxiliary hydraulic oil tank, and being used to open when the current pressure of the back pressure valve reaches a second preset pressure, so that the return oil flows to the main hydraulic oil tank and the auxiliary hydraulic oil tank.

[0010] The present invention deploys a back-pressure valve and a bypass valve in the hydraulic oil return control unit, which can control the valve opening based on the return oil pressure. When the return oil volume is small, only the back-pressure valve is opened. When the return oil volume is large, a bypass valve is added to improve the flow capacity and ensure that all the return oil is discharged into the hydraulic oil tank, avoiding the occurrence of cavitation caused by hydraulic circuit blockage.

[0011] In an optional embodiment, the system also includes: a first control valve and a second control valve, and the anti-cavitation control unit includes: a proportional control solenoid valve; a first control valve, a first end of which is connected to the input end of the auxiliary hydraulic oil tank, and a second end is connected to the second end of the bypass valve, for adjusting the hydraulic oil input of the auxiliary hydraulic oil tank; a second control valve, a first end of which is connected to the output end of the auxiliary hydraulic oil tank, and a second end is connected to the plunger hydraulic main pump and the pilot gear pump, for adjusting the hydraulic oil output of the auxiliary hydraulic oil tank; a proportional control solenoid valve, a control end of which is connected to the control unit, an input end of which is connected to the pilot gear pump, and an output end of which is connected to the driving end of the first control valve and the driving end of the second control valve, for opening under a control instruction generated by the control unit based on the oil suction condition of the hydraulic oil supply unit, and outputting the pilot control oil to the first control valve and the second control valve, so that the first control valve and the second control valve are opened synchronously.

[0012] By deploying a proportional control solenoid valve, the present invention can synchronously control the opening of the control valves at both ends of the auxiliary hydraulic oil tank through the opening of the proportional control solenoid valve, so as to allow the hydraulic oil in the auxiliary hydraulic oil tank to enter the hydraulic circulation based on the physical structure, and realize fixed-point compensation when the hydraulic pump lacks oil suction, which helps to maintain the constancy of the system pressure, avoid pressure fluctuations that affect the control performance, and thus improve the utilization efficiency of the hydraulic oil energy and avoid the loss of engine power.

[0013] In an optional embodiment, the system also includes: an oil level sensor and an oil suction pressure sensor; the oil level sensor is deployed in the auxiliary hydraulic oil tank to detect the oil level of the auxiliary hydraulic oil tank; the oil suction pressure sensor is deployed in the plunger hydraulic main pump and the oil suction pipeline between the main hydraulic oil tank and the auxiliary hydraulic oil tank to detect the oil suction pressure of the oil suction pipeline.

[0014] By deploying an oil level sensor and an oil suction pressure sensor, the present invention can accurately measure the oil suction condition of the hydraulic pump, and then adjust the conduction condition of the hydraulic circulation pipeline according to the oil suction condition to avoid the occurrence of hydraulic pump air suction.

[0015] In the second aspect, the present invention provides a hydraulic pump control method, the hydraulic pump control system includes a control unit, a hydraulic oil supply unit, an execution unit, a hydraulic oil return control unit, a main hydraulic oil tank, an auxiliary hydraulic oil tank and an anti-cavitation control unit, and the control method is applied to the control unit, the method including: obtaining the hydraulic oil demand of the execution unit, and controlling the hydraulic oil supply unit to suck in hydraulic oil according to the hydraulic oil demand to provide working oil for the execution unit; controlling the working state of the hydraulic oil return control unit according to the return oil condition of the execution unit so that the return oil of the execution unit flows to the main hydraulic oil tank or the main hydraulic oil tank and the auxiliary hydraulic oil tank; controlling the working state of the anti-cavitation control unit according to the suction condition of the hydraulic oil supply unit so that the hydraulic oil of the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank enters the hydraulic oil supply unit.

[0016] The hydraulic pump control method provided by the present invention controls the operating states of the hydraulic oil return control unit and the anti-cavitation control unit based on the return oil condition and the oil suction condition, so that the return oil of the execution unit enters the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, so that the hydraulic oil supply unit draws hydraulic oil from the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, to provide working oil for the execution unit. By deploying the anti-cavitation control unit and adjusting the control logic, the present invention can control the hydraulic oil of the auxiliary hydraulic oil pump to participate in the circulation of the hydraulic system according to the operating state of the hydraulic pump, realize intelligent control of the hydraulic pump oil suction based on the physical structure, ensure the stable operation of the hydraulic pump under various working conditions, play a protective role for the hydraulic pump, and thus ensure the normal progress of engineering operations.

[0017] In an optional embodiment, the hydraulic oil return control unit includes: a back pressure valve and a bypass valve; the working state of the hydraulic oil return control unit is controlled according to the return oil condition of the execution unit, so that the return oil of the execution unit flows to the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, including: obtaining the current pressure of the back pressure valve, and judging whether the current pressure is higher than the first preset pressure or the second preset pressure, the first preset pressure is less than the second preset pressure; if the current pressure is higher than the first preset pressure, the back pressure valve is controlled to open so that the return oil flows to the main hydraulic oil tank; if the current pressure is higher than the second preset pressure, when the back pressure valve is opened, the bypass valve is controlled to open so that the return oil flows to the main hydraulic oil tank and the auxiliary hydraulic oil tank.

[0018] The present invention controls the conduction and closing of the back pressure valve and the bypass valve in the hydraulic oil return control unit, and can expand the return oil flow by adding the bypass valve, so as to adjust the return oil direction according to the actual return oil condition. In the state of large flow and large oil suction demand of the hydraulic pump, it is ensured that the return oil of the execution unit is completely discharged into the hydraulic oil tank, thereby preliminarily avoiding the occurrence of hydraulic pump air suction.

[0019] 14. The jackup plan of claim 13, wherein the jackup plan is a control plan of the hydraulic pump, the jackup plan is a control plan of the hydraulic pump, and the jackup plan is a control plan of the hydraulic pump, the jackup plan is a control plan of the hydraulic pump, and the jackup plan is a control plan of the hydraulic pump, the jackup plan is a control plan of the hydraulic pump, and the jackup plan is a control plan of the hydraulic pump, the jackup plan is a control plan of the hydraulic pump, and the jackup plan is a control plan of the hydraulic pump, The proportional control solenoid valve is controlled to be closed so that the hydraulic oil in the main hydraulic oil tank enters the hydraulic oil supply unit; if the oil suction pressure is lower than the third preset pressure, the current opening of the proportional control solenoid valve is controlled according to the oil suction pressure, so that the first control valve and the second control valve are opened synchronously, the return oil enters the auxiliary hydraulic oil tank according to the preset flow, and the hydraulic oil in the auxiliary hydraulic oil tank enters the hydraulic oil supply unit according to the preset flow; if the oil suction pressure is lower than the fourth preset pressure, the proportional control solenoid valve is controlled to be opened to the maximum opening, so that the first control valve and the second control valve are opened to the maximum opening synchronously, the return oil enters the auxiliary hydraulic oil tank according to the maximum flow, and the hydraulic oil in the auxiliary hydraulic oil tank enters the hydraulic oil supply unit according to the maximum flow.

[0020] The present invention controls the opening and closing of the proportional control solenoid valve in the anti-cavitation control unit according to the oil suction pressure, and can connect the input and output ends of the auxiliary hydraulic oil tank based on the action of the pilot control oil, so that the hydraulic oil of the auxiliary hydraulic oil pump participates in the circulation of the hydraulic system, further avoiding the occurrence of cavitation in the hydraulic pump.

[0021] In an optional embodiment, the auxiliary hydraulic oil tank is equipped with an oil level sensor. In the process of controlling the working state of the anti-cavitation control unit according to the oil suction condition of the hydraulic oil supply unit so that the hydraulic oil of the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank enters the hydraulic oil supply unit, it also includes: obtaining the real-time oil level of the auxiliary hydraulic oil tank, and judging whether the real-time oil level changes. If it changes, a first alarm signal is generated; judging whether the oil suction pressure is lower than the fifth preset pressure, and the fifth preset pressure is less than the fourth preset pressure. If it is less than the fifth preset pressure, the control strategy is adjusted and a second alarm signal is generated.

[0022] By detecting the oil level in the auxiliary hydraulic tank, the present invention accurately reflects the stability of the hydraulic pump's oil suction and return, enabling fixed-point compensation when the hydraulic pump's oil suction is insufficient. This helps maintain constant system pressure and prevents pressure fluctuations that affect operating performance. Furthermore, an alarm is issued when the oil suction pressure is too low, promptly alerting the operator when the hydraulic pump is empty, preventing damage to the hydraulic system.

[0023] In a third aspect, the present invention provides an engineering machinery device, comprising the hydraulic pump control system of the first aspect or any corresponding embodiment thereof.

[0024] Because the engineering machinery equipment includes a hydraulic pump control system, which has the same effect as the hydraulic pump control system, it will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 is a structural block diagram of a hydraulic pump control system according to an embodiment of the present invention;

[0027] Figure 2 is a flow chart of a hydraulic pump control method according to an embodiment of the present invention;

[0028] Figure 3 4 is a flow chart of another hydraulic pump control method according to an embodiment of the present invention.

[0029] Description of the accompanying drawings: 100-hydraulic oil supply unit; 101-power unit; 102-plunger hydraulic main pump; 103-guide gear pump; 200-executor unit; 201-control device; 202-executor mechanism; 300-hydraulic oil return control unit; 301-back pressure valve; 302-bypass valve; 303-first throttle valve; 304-second throttle valve; 400-main hydraulic oil tank; 401-oil dipstick; 402-first return oil filter; 403-first suction oil filter; 500-auxiliary hydraulic oil tank; 501-oil level sensor; 502-second return oil filter; 503-second suction oil filter; 600-anti-cavitation control unit; 601-solenoid valve; 701-first control valve; 702-second control valve; 801-suction oil pressure sensor; 802-working pressure sensor; 900-hydraulic oil cooling unit. DETAILED DESCRIPTION

[0030] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0031] The embodiments of the present invention are applicable to application scenarios in which the hydraulic oil circulation of the hydraulic system is adjusted according to the operating conditions when engineering machinery equipment is operating to prevent the hydraulic oil from being sucked out of the system. Taking a mining excavator as an example, the hydraulic system of the excavator usually adopts a constant power control method to ensure its efficient and stable operation. Constant power control follows the basic formula of "power = pressure × flow". By adjusting the output flow of the hydraulic pump in real time, it ensures that the system always maintains constant power under different load conditions, thereby achieving a balance between energy saving and performance. However, this control method has the potential risk of hydraulic pump sucking out of the system when facing drastic changes in load. For example, when the excavator is performing excavation operations, the hydraulic system needs to overcome the resistance of materials such as soil and rock. At this time, the load is extremely high (the pressure becomes larger). According to the constant power control principle, in order to ensure constant power, the hydraulic pump will automatically reduce the output flow. As the output flow decreases, the return oil flow of the hydraulic system also decreases, and the entire system is in a high-pressure and low-flow operating state. When the excavation action is completed and the load is instantly reduced, such as when the bucket is extracted from the soil or materials are quickly unloaded, the actuators (such as hydraulic cylinders and hydraulic motors) need to quickly complete reset and rotation actions. This requires the hydraulic pump to provide a large amount of hydraulic oil in a short period of time to achieve high-speed operation. The hydraulic pump immediately increases the output flow rate, and the return oil flow rate also increases instantly. However, the hydraulic pump's oil suction capacity has an upper limit. When the system's demand for flow increases sharply, exceeding the hydraulic pump's maximum oil suction capacity, cavitation problems will occur.

[0032] Hydraulic pump cavitation essentially refers to the mixing of air into the hydraulic fluid during the pump's suction process due to the pressure within the suction chamber falling below atmospheric pressure. When the load decreases momentarily, the pump's output flow increases dramatically, and the suction port is unable to replenish sufficient hydraulic fluid in a timely manner, causing the pressure within the suction chamber to drop rapidly. Once the pressure drops below a certain level, below the air separation pressure, the air previously dissolved in the hydraulic fluid precipitates, forming bubbles. If the pressure drops further below atmospheric pressure, outside air can also enter the system through seals and other areas in the suction line. These bubbles enter the hydraulic pump along with the hydraulic fluid. When they reach high-pressure areas, they rapidly burst, generating localized high temperatures and high-pressure shocks. This not only causes vibration and noise, but can also cause cavitation damage to the pump's internal components, seriously impacting the pump's service life and the system's stable operation.

[0033] In this case, the related art primarily utilizes the hydraulic pump's main pressure for suction compensation. The system includes a hydraulic pump, a cartridge valve, and an on-off valve. The hydraulic pump's suction port is connected to the fuel tank. The on-off valve is controlled by the suction port pressure, thereby connecting the cartridge valve to the fuel tank. The pressure differential between the fuel outlet and the fuel tank activates the cartridge valve, connecting the suction port and the fuel outlet. At this point, hydraulic oil from the fuel outlet can be replenished to the suction port. However, this process can cause sudden fluctuations in the hydraulic pump's operating flow rate and pressure, impacting the entire excavator's operation. Furthermore, if the hydraulic pump's main pressure is too high, even with pressure and throttle valve control, accurate and efficient suction pressure compensation cannot be achieved. Furthermore, this system fails to protect the hydraulic pump. Excessive suction pressure can damage the seals in the hydraulic pump's suction plate or cause a pipe burst. Furthermore, it cannot accurately control the required hydraulic oil flow caused by cavitation in the hydraulic pump, resulting in wasted hydraulic oil energy and loss of engine power. Therefore, an embodiment of the present invention provides a hydraulic pump control method, which deploys a main hydraulic oil tank and an auxiliary hydraulic oil tank, adjusts the hydraulic circulation direction according to the return oil condition and the oil suction condition, and enables the hydraulic oil in the auxiliary hydraulic oil tank to participate in the hydraulic circulation in time, so as to prevent the hydraulic pump from being sucked out of the water.

[0034] According to an embodiment of the present invention, a hydraulic pump control system embodiment is provided. It should be noted that, as used below, the term "module" may refer to a combination of software and / or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, implementation using hardware, or a combination of software and hardware, is also possible and contemplated.

[0035] In this embodiment, a hydraulic pump control system is provided. Figure 1 As shown in the structural block diagram, the system includes: a control unit, a hydraulic oil supply unit 100, an execution unit 200, a hydraulic oil return control unit 300, a main hydraulic oil tank 400, an auxiliary hydraulic oil tank 500 and an anti-cavitation control unit 600; the hydraulic oil supply unit 100, the input end of which is connected to the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500, and the output end of which is connected to the first end of the execution unit 200, is used to absorb hydraulic oil from the main hydraulic oil tank 400, or the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500, to provide working oil for the execution unit 200; the hydraulic oil return control unit 300 Unit 300 is connected to the second end of the execution unit 200, and is used to adjust the direction of the return oil of the execution unit 200 so that the return oil flows to the main hydraulic oil tank 400, or the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500; the anti-cavitation control unit 600 is connected to the output end of the hydraulic oil supply unit 100, and is used to control the hydraulic oil of the auxiliary hydraulic oil tank 500 to enter the hydraulic oil supply unit 100; the control unit is connected to the hydraulic oil return control unit 300 and the anti-cavitation control unit 600, and is used to control the working status of the hydraulic oil return control unit and the anti-cavitation control unit.

[0036] Specifically, in the embodiment of the present invention, Figure 1 As shown, the hydraulic oil supply unit 100 includes: a power device 101, a plunger hydraulic main pump 102 and a pilot gear pump 103; the power device 101 is connected to the driving end of the plunger hydraulic main pump 102 and the driving end of the pilot gear pump 103, and is used to provide hydraulic energy to the plunger hydraulic main pump 102 and the pilot gear pump 103; the plunger hydraulic main pump 102, the input end is connected to the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500, and the output end is connected to the execution unit 200, Used to suck hydraulic oil from the main hydraulic oil tank 400, or the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500, to provide working oil for the execution unit 200; the pilot gear pump 103, the input end of which is connected to the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500, and the output end is connected to the anti-cavitation control unit 600, to suck hydraulic oil from the main hydraulic oil tank 400, or the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500, to provide pilot control oil for the anti-cavitation control unit 600.

[0037] In some optional embodiments, such as Figure 1 As shown, the hydraulic oil return control unit 300 includes: a back pressure valve 301, a bypass valve 302, a first throttle valve 303 and a second throttle valve 304. The back pressure valve 301 has a first end connected to the execution unit 200 and a second end connected to the main hydraulic oil tank 400, and is used to open when the current pressure of the back pressure valve 301 reaches a first preset pressure, so that the return oil flows to the main hydraulic oil tank 400; the bypass valve 302 has a first end connected to the execution unit 200, and a second end connected to the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500, and is used to open when the current pressure of the back pressure valve 301 reaches a second preset pressure, so that the return oil flows to the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500.

[0038] In some optional embodiments, such as Figure 1As shown, the system further includes: a first control valve 701 and a second control valve 702. The anti-cavitation control unit 600 includes: a proportional control solenoid valve 601; the first control valve 701, the first end of which is connected to the input end of the auxiliary hydraulic oil tank 500, and the second end of which is connected to the second end of the bypass valve 302, and is used to adjust the hydraulic oil input amount of the auxiliary hydraulic oil tank 500, that is, to control the flow between the hydraulic oil return control unit 300 and the auxiliary hydraulic oil tank 500, and to control the size of the open flow hole by providing pressure through the proportional control solenoid valve 601; the second control valve 702, the first end of which is connected to the output end of the auxiliary hydraulic oil tank 500, and the second end of which is connected to the plunger hydraulic main pump 102 and the pilot gear pump 103. Used to adjust the hydraulic oil output of the auxiliary hydraulic oil tank 500, that is, to control the flow between the plunger hydraulic main pump 102 and the auxiliary hydraulic oil tank 500, and to provide pressure control to open the flow hole size through the proportional control solenoid valve 601; the proportional control solenoid valve 601, the control end is connected to the control unit, the input end is connected to the pilot gear pump 103, and the output end is connected to the driving end of the first control valve 701 and the driving end of the second control valve 702, and is used to open under the control instruction generated by the control unit based on the oil suction condition of the hydraulic oil supply unit, and output the pilot control oil to the first control valve 701 and the second control valve 702, so that the first control valve 701 and the second control valve 702 are opened synchronously.

[0039] In some optional embodiments, such as Figure 1 As shown, the system also includes: an oil level sensor 501 and an oil suction pressure sensor 801; the oil level sensor 501 is deployed in the auxiliary hydraulic oil tank 500, and is used to detect the oil level of the auxiliary hydraulic oil tank 500; the oil suction pressure sensor 801 is deployed in the plunger hydraulic main pump 102 and the oil suction pipeline between the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500, and is used to detect the oil suction pressure of the oil suction pipeline.

[0040] In some optional embodiments, such as Figure 1As shown, the actuator unit 200 includes a control device 201 and an actuator 202. The control device 201 is used to control the opening and closing of the valve core to change the operation of the actuator 202, such as a multi-way valve. A hydraulic oil heat sink 900 is also located between the hydraulic oil return control unit 300 and the main hydraulic oil tank 400 to provide constant temperature protection for the hydraulic system. The main hydraulic oil tank 400 includes an oil dipstick 401 for monitoring the oil level in the main hydraulic oil tank 400; a first return oil filter 402 for filtering hydraulic oil impurities; and a first suction oil filter 403 for filtering hydraulic oil impurities. The auxiliary hydraulic oil tank 500 includes an oil level sensor 501 for constantly monitoring the oil level in the auxiliary hydraulic oil tank 500; a second return oil filter 502 for filtering hydraulic oil impurities; and a second suction oil filter 503 for filtering hydraulic oil impurities. The first control valve 701 and the second control valve 702 contain check valves to establish line pressure and prevent hydraulic oil backflow. A working pressure sensor 802 is deployed in the working pipeline between the hydraulic oil supply unit 100 and the execution unit 200 to detect the main pressure of the hydraulic pump at all times for auxiliary detection and judgment. When the pressure value of the working pressure sensor 802 is detected to be lower than 10MPa, it is a high flow demand state, and the anti-cavitation strategy has been assisted in controlling to prevent the oil suction pressure sensor 801 in the oil suction pipeline from being damaged and the system failing to detect the impact in time.

[0041] The hydraulic pump control system provided by the present invention controls the operating states of the hydraulic oil return control unit and the anti-cavitation control unit through a control unit. The anti-cavitation control unit controls the hydraulic oil in the auxiliary hydraulic oil tank to enter the hydraulic oil supply unit. The hydraulic oil return control unit adjusts the direction of the return oil from the execution unit so that the return oil enters the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, so that the hydraulic oil supply unit draws hydraulic oil from the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, to provide working oil for the execution unit. By deploying the anti-cavitation control unit, the present invention can control the hydraulic oil of the auxiliary hydraulic oil pump to participate in the circulation of the hydraulic system according to the operating state of the hydraulic pump, realize intelligent control of the hydraulic pump oil suction based on the physical structure, ensure the stable operation of the hydraulic pump under various working conditions, play a protective role for the hydraulic pump, and thus ensure the normal progress of engineering operations.

[0042] According to an embodiment of the present invention, an embodiment of a hydraulic pump control method is also provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0043] In this embodiment, a hydraulic pump control method is provided, which can be used in a control unit of a hydraulic pump control system. Figure 2is a flow chart of a hydraulic pump control method according to an embodiment of the present invention. Figure 2 As shown, the process includes the following steps:

[0044] Step S201 , obtaining the hydraulic oil demand of the execution unit, and controlling the hydraulic oil supply unit to absorb hydraulic oil according to the hydraulic oil demand, so as to provide working oil for the execution unit.

[0045] Specifically, in the embodiment of the present invention, Figure 1 As shown, the hydraulic pump control system includes: a hydraulic oil supply unit 100, an execution unit 200, a hydraulic oil return control unit 300, a main hydraulic oil tank 400, an auxiliary hydraulic oil tank 500 and an anti-cavitation control unit 600. The hydraulic pump control system also includes a control unit, but it is not shown in FIG. Figure 1 The hydraulic oil supply unit 100 is connected to the execution unit 200 via a working pipeline, the execution unit 200 is connected to the hydraulic oil return control unit 300, and the hydraulic oil return control unit 300 is connected to the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500 via an oil return pipeline, and the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500 are connected to the hydraulic oil supply unit 100 via an oil suction pipeline.

[0046] In some optional embodiments, such as Figure 1 As shown, the hydraulic oil supply unit 100 includes a power unit 101, a plunger hydraulic main pump 102, and a pilot gear pump 103. Based on constant power control, the control unit in this embodiment of the present invention determines the hydraulic demand based on the load pressure of the actuator 200, and then adjusts the power unit 101 based on the hydraulic demand, so that the power unit 101 provides corresponding hydraulic energy to the plunger hydraulic main pump 102. The plunger hydraulic main pump 102 draws oil from the main hydraulic oil tank 400 or the auxiliary hydraulic oil tank 500, and then sucks the hydraulic oil into the actuator 200, thereby providing working oil for the actuator 200. When the actuator 200 (such as a hydraulic cylinder, hydraulic motor, etc.) completes its work under the action of the hydraulic oil, the hydraulic oil reaches the hydraulic oil return control unit 300 through the return oil pipeline.

[0047] Step S202 : controlling the working state of the hydraulic oil return control unit according to the oil return status of the execution unit, so that the return oil of the execution unit flows to the main hydraulic oil tank or the main hydraulic oil tank and the auxiliary hydraulic oil tank.

[0048] Specifically, in the embodiment of the present invention, Figure 1As shown, the hydraulic oil return control unit 300 includes: a back pressure valve 301, which can establish the hydraulic system return oil back pressure; a bypass valve 302, which can connect the main and auxiliary hydraulic oil tanks to return oil to prevent the system return oil pressure from being too high; and also includes: a first throttle valve 303, which can prevent pressure fluctuations after the back pressure valve is opened; a second throttle valve 304, which can prevent pressure fluctuations after the bypass valve is opened, and stabilize the system return oil back pressure.

[0049] In some optional embodiments, the control unit determines whether to open the back-pressure valve 301, or to open the back-pressure valve 301 and the bypass valve 302, based on the current pressure of the back-pressure valve 301. During this process, the first throttle valve 303 and the second throttle valve 304 automatically adjust the pressure of the back-pressure valve 301 or the bypass valve 302 by adjusting the return oil flow. When the return oil flow is small, only the back-pressure valve 301 is opened, and the return oil can only flow into the main hydraulic oil tank 400 through the back-pressure valve 301. When the return oil flow is large, the flow capacity of the back-pressure valve 301 is insufficient to drain all the hydraulic oil. The back-pressure valve 301 and the bypass valve 302 are opened simultaneously, and the return oil is divided through the back-pressure valve 301 and the bypass valve 302, with one portion flowing directly into the main hydraulic oil tank 400 and the other portion flowing into the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500 respectively.

[0050] Step S203 , controlling the working state of the anti-cavitation control unit according to the oil suction condition of the hydraulic oil supply unit, so that the hydraulic oil in the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, enters the hydraulic oil supply unit.

[0051] Specifically, in the embodiment of the present invention, Figure 1 As shown, one end of the anti-cavitation control unit 600 is connected to the pilot gear pump 103, and the other end is connected to two control valves: a first control valve 701 and a second control valve 702. The first control valve 701 is located between the input end of the auxiliary hydraulic oil tank 500 and the bypass valve 302, and the second control valve 702 is located between the output end of the auxiliary hydraulic oil tank 500 and the hydraulic oil supply unit 100. A suction pressure sensor 801 is installed on the suction line between the output end of the auxiliary hydraulic oil tank 500 and the hydraulic oil supply unit 100 to detect the suction pressure of the suction line. The suction pressure reflects the suction status of the hydraulic oil supply unit 100, and the suction status changes synchronously with the return oil status. If the suction pressure is too low, it indicates that the hydraulic oil is insufficient, the return oil flow is large, and cavitation may occur.

[0052] In an optional embodiment, as Figure 1As shown, the pilot gear pump 103 draws oil based on the hydraulic energy provided by the power unit 101, providing pilot control oil to the anti-cavitation control unit 600. This embodiment of the present invention adjusts and controls the operating state of the anti-cavitation control unit 600 based on the suction pressure. When the suction pressure is high, the anti-cavitation control unit 600 is not activated, and the input and output ends of the auxiliary hydraulic oil tank 500 are disconnected. At this time, the return oil, after passing through the back pressure valve 301 and the bypass valve 302, enters the main hydraulic oil tank 400. Only the hydraulic oil in the main hydraulic oil tank 400 can enter the plunger hydraulic main pump 102 through the suction line. In other words, only the hydraulic oil in the main hydraulic oil tank 400 needs to participate in the hydraulic circulation to meet the current working conditions.

[0053] In an optional embodiment, when the suction pressure is low, it proves that the demand for hydraulic oil increases, the return oil flow increases, and the hydraulic oil in the main hydraulic oil tank 400 is insufficient to maintain the current working condition. At this time, the bypass valve 302 is opened, and the anti-cavitation control unit 600 is opened synchronously. The pilot control oil flows through the anti-cavitation control unit 600 to the first control valve 701 and the second control valve 702. The first control valve 701 and the second control valve 702 are opened under the pressure of the pilot control oil, thereby connecting the input and output ends of the auxiliary hydraulic oil tank 500. At this time, part of the return oil enters the main hydraulic oil tank 400 after passing through the back pressure valve 301, and the other part enters the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500 respectively after passing through the bypass valve 302. The hydraulic oil in the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500 can both enter the plunger hydraulic main pump 102 through the suction line, that is, the hydraulic oil in the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500 can jointly participate in the hydraulic circulation to meet the current working condition.

[0054] The hydraulic pump control method provided by the present invention controls the operating states of the hydraulic oil return control unit and the anti-cavitation control unit based on the return oil condition and the oil suction condition, so that the return oil of the execution unit enters the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, so that the hydraulic oil supply unit draws hydraulic oil from the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, to provide working oil for the execution unit. By deploying the anti-cavitation control unit and adjusting the control logic, the present invention can control the hydraulic oil of the auxiliary hydraulic oil pump to participate in the circulation of the hydraulic system according to the operating state of the hydraulic pump, realize intelligent control of the hydraulic pump oil suction based on the physical structure, ensure the stable operation of the hydraulic pump under various working conditions, play a protective role for the hydraulic pump, and thus ensure the normal progress of engineering operations.

[0055] In this embodiment, a hydraulic pump control method is provided, which can be used in a control unit of a hydraulic pump control system. Figure 3 : is a flow chart of the hydraulic pump control according to an embodiment of the present invention, as shown in FIG. Figure 3 As shown, the process includes the following steps:

[0056] Step S301: Obtain the hydraulic oil demand of the execution unit, and control the hydraulic oil supply unit to absorb hydraulic oil according to the hydraulic oil demand to provide working oil for the execution unit. Figure 2 Step S201 of the illustrated embodiment will not be described in detail here.

[0057] Step S302 : controlling the working state of the hydraulic oil return control unit according to the oil return status of the execution unit, so that the return oil of the execution unit flows to the main hydraulic oil tank or the main hydraulic oil tank and the auxiliary hydraulic oil tank.

[0058] Specifically, the above step S302 includes:

[0059] Step S3021, obtaining the current pressure of the back pressure valve, and determining whether the current pressure is higher than the first preset pressure or the second preset pressure, the first preset pressure being lower than the second preset pressure.

[0060] Specifically, in an embodiment of the present invention, during the operation of the excavator, high-pressure hydraulic oil is provided to the execution unit 200 corresponding to the working device through the plunger hydraulic main pump 102, and the hydraulic oil in the low-pressure area of ​​the execution unit 200 enters the hydraulic oil return control unit 300. The back pressure valve 301 in the hydraulic oil return control unit 300 establishes the return oil back pressure and determines whether the current pressure of the return oil back pressure reaches the first preset pressure, for example, 0.5 bar, but not limited to this.

[0061] Step S3022: If the current pressure is higher than the first preset pressure, the back pressure valve is controlled to open so that the return oil flows to the main hydraulic oil tank.

[0062] Specifically, in this embodiment of the present invention, if the current pressure corresponding to the return oil back pressure reaches 0.5 bar, it indicates that return oil is present and the return oil flow rate is small. It is necessary to open the back pressure valve 301 to allow the high-temperature hydraulic oil to enter the heat sink for heat dissipation before entering the main hydraulic oil tank 400. At this time, the flow capacity of the back pressure valve 301 is sufficient to drain all the return oil into the main hydraulic oil tank.

[0063] In some optional embodiments, the back pressure valve 301 may be controlled to open by a control unit, and a back pressure valve 301 that can automatically open according to pressure may also be selected, which is not limited here.

[0064] Step S3023: If the current pressure is higher than the second preset pressure, when the back pressure valve is opened, the bypass valve is controlled to open so that the return oil flows to the main hydraulic oil tank and the auxiliary hydraulic oil tank.

[0065] Specifically, in the embodiment of the present invention, when the hydraulic demand of the execution unit 200 increases, the oil suction volume increases, and the return oil flow rate continues to increase, the flow capacity of the back pressure valve 301 is insufficient to drain all the hydraulic oil, resulting in an increase in the current pressure corresponding to the return oil back pressure. If the current pressure reaches the second preset pressure, for example, 2 bar, the bypass valve 302 is opened, and the excess hydraulic oil flows to the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500 through the bypass valve. However, if Figure 1 As shown, control valves are deployed at both ends of the auxiliary hydraulic oil tank 500. If the control valves are not opened, all the excess hydraulic oil enters the main hydraulic oil tank 400. If the control valves are opened, the excess hydraulic oil enters the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500 respectively.

[0066] Step S303 , controlling the working state of the anti-cavitation control unit according to the oil suction condition of the hydraulic oil supply unit, so that the hydraulic oil in the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, enters the hydraulic oil supply unit.

[0067] Specifically, the above step S303 includes:

[0068] Step S3031, obtaining the oil suction pressure of the oil suction pipeline, and determining whether the oil suction pressure is lower than a third preset pressure or a fourth preset pressure, and the third preset pressure is greater than the fourth preset pressure.

[0069] Specifically, in the embodiment of the present invention, Figure 1 As shown, an oil suction pressure sensor 801 is deployed in the oil suction line. The control unit obtains the measured oil suction pressure of the oil suction line and determines whether the oil suction pressure is lower than a third preset pressure, for example, 0.15 bar, but not limited to this. In this case, the lower the oil suction pressure, the lower the oil suction volume. However, the return oil flow rate is relatively large, indicating an increase in hydraulic demand. As the hydraulic oil drawn by the plunger hydraulic main pump 102 increases accordingly, insufficient oil suction will cause the oil suction line pressure to decrease. If no adjustment is made at this time, the hydraulic pump may become emptied, resulting in negative pressure in the oil suction line.

[0070] Step S3032: If the oil suction pressure is not lower than the third preset pressure, the proportional control solenoid valve is controlled to close, so that the hydraulic oil in the main hydraulic oil tank enters the hydraulic oil supply unit.

[0071] Specifically, in the embodiment of the present invention, Figure 1As shown, the anti-cavitation control unit 600 houses a proportional control solenoid valve 601. The control unit controls the opening and closing of the proportional control solenoid valve 601 based on the comparison between the suction pressure and a third preset pressure. If the suction pressure is at least 0.15 bar, cavitation will not occur, so the proportional control solenoid valve 601 remains closed. If the proportional control solenoid valve 601 is closed, the pilot oil cannot flow to the first and second control valves 701 and 702, blocking the connection between the two ends of the auxiliary hydraulic oil tank 500. Therefore, only the hydraulic oil from the main hydraulic oil tank 400 can enter the plunger hydraulic main pump 102 through the suction line, thereby participating in the hydraulic circulation.

[0072] Step S3033, if the oil suction pressure is lower than the third preset pressure, the current opening of the solenoid valve is controlled proportionally according to the oil suction pressure control so that the first control valve and the second control valve are opened synchronously, and the return oil enters the auxiliary hydraulic oil tank according to the preset flow rate, and the hydraulic oil in the auxiliary hydraulic oil tank enters the hydraulic oil supply unit according to the preset flow rate.

[0073] Specifically, in an embodiment of the present invention, if the oil suction pressure is lower than 0.15 bar, it proves that air suction may occur at this time, so the proportional control solenoid valve 601 is controlled to open. If the proportional control solenoid valve 601 is opened, the pilot control oil flows to the first control valve 701 and the second control valve 702. The first control valve 701 and the second control valve 702 are opened synchronously under the pressure of the pilot control oil, and the two ends of the auxiliary hydraulic oil tank 500 are connected, so the return oil can enter the auxiliary hydraulic oil tank 500, and the hydraulic oil of the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500 can enter the plunger hydraulic main pump 102 through the oil suction pipeline at the same time, and participate in the hydraulic circulation together.

[0074] In some optional embodiments, the proportional control solenoid valve is a hydraulic component that accurately controls the flow, pressure or direction of hydraulic oil through electrical signals. Therefore, the control unit can control the current value provided to the proportional control solenoid valve 601 according to the oil suction pressure. The current value is different (for example: the current value is 200mA-600mA, 200mA represents open, and 600mA represents fully open). The opening of the proportional control solenoid valve 601 is different, and then by controlling the flow of the pilot control oil, the opening of the first control valve 701 and the second control valve 702 are synchronously controlled, so that the return oil enters the auxiliary hydraulic oil tank 500 according to the corresponding flow rate, and the hydraulic oil in the auxiliary hydraulic oil tank 500 enters the hydraulic oil supply unit 100 according to the same flow rate, that is, the return oil volume and the suction oil volume of the auxiliary hydraulic oil tank 500 are kept synchronized.

[0075] Step S3034, if the oil suction pressure is lower than the fourth preset pressure, the proportional control solenoid valve is controlled to open to the maximum opening, so that the first control valve and the second control valve are synchronously opened to the maximum opening, and the return oil enters the auxiliary hydraulic oil tank at the maximum flow rate, and the hydraulic oil in the auxiliary hydraulic oil tank enters the hydraulic oil supply unit at the maximum flow rate.

[0076] Specifically, in this embodiment of the present invention, if the suction pressure continues to decrease, it indicates that the demand for hydraulic oil continues to increase, and cavitation has not been prevented, so the suction volume needs to be increased. Therefore, if the suction pressure is lower than a fourth preset pressure, for example, -0.25 bar, the control unit controls the proportional control solenoid valve 601 to open to its maximum opening, and then the pilot control oil acts on the first control valve 701 and the second control valve 702 at its maximum flow rate, causing the first control valve 701 and the second control valve 702 to open synchronously to their maximum openings. At this time, the return oil enters the auxiliary hydraulic oil tank 500 at its maximum flow rate, and the hydraulic oil in the auxiliary hydraulic oil tank 500 enters the hydraulic oil supply unit 100 at the same maximum flow rate, that is, the return oil volume and the suction oil volume of the auxiliary hydraulic oil tank 500 are always synchronized.

[0077] In some optional embodiments, to ensure that the return and intake volumes of the auxiliary hydraulic oil tank 500 remain synchronized and the fluid level of the auxiliary hydraulic oil tank 500 is always maintained at an optimal position, an oil level sensor 501 is deployed in the auxiliary hydraulic oil tank 500 to detect the real-time oil level of the auxiliary hydraulic oil tank 500. If the real-time oil level changes, an alarm signal is generated. This oil level detection can prevent the first and second control valves 701 and 702 from experiencing functional damage that is difficult to detect, leading to fluid level changes. For example, this can prevent the second control valve 702 from accidentally damaging when only oil is being returned, causing hydraulic oil to overflow from the auxiliary hydraulic oil tank 500. It can also prevent the first control valve 701 from accidentally damaging when only oil is being inflowed, causing the hydraulic oil in the auxiliary hydraulic oil tank 500 to be completely drained, resulting in a high negative pressure and damaging the auxiliary hydraulic oil tank 500 and the hydraulic pump.

[0078] Step S3035, determining whether the oil suction pressure is lower than the fifth preset pressure, the fifth preset pressure is lower than the fourth preset pressure, if it is lower than the fifth preset pressure, adjusting the control strategy and generating a second alarm signal.

[0079] Specifically, in an embodiment of the present invention, extreme situations are taken into consideration, that is, if the main hydraulic oil tank 400 and the auxiliary hydraulic oil tank 500 participate in the hydraulic circulation at their maximum capacity and still cannot meet the current hydraulic oil demand, the oil suction pressure will continue to decrease. When it drops to the fifth preset pressure, for example, the minimum pressure value required by the hydraulic pump -0.5 bar, an alarm signal is generated in time, and the control strategy is adjusted at the same time, for example, by reducing the displacement of the hydraulic pump to reduce the flow rate required by the hydraulic pump.

[0080] The hydraulic pump control method provided by the present invention controls the operating states of the hydraulic oil return control unit and the anti-cavitation control unit based on the return oil condition and the oil suction condition, so that the return oil of the execution unit enters the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, so that the hydraulic oil supply unit draws hydraulic oil from the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, to provide working oil for the execution unit. By deploying the anti-cavitation control unit and adjusting the control logic, the present invention can control the hydraulic oil of the auxiliary hydraulic oil pump to participate in the circulation of the hydraulic system according to the operating state of the hydraulic pump, realize intelligent control of the hydraulic pump oil suction based on the physical structure, ensure the stable operation of the hydraulic pump under various working conditions, play a protective role for the hydraulic pump, and thus ensure the normal progress of engineering operations.

[0081] The embodiment of the present invention further provides an engineering machinery device, comprising the above Figure 1 The hydraulic pump control system shown is for example an excavator.

[0082] Although the embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention. Such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A hydraulic pump control system, characterized in that: include: Control unit, hydraulic oil supply unit, execution unit, hydraulic oil return control unit, main hydraulic oil tank, auxiliary hydraulic oil tank and anti-cavitation control unit; The hydraulic oil supply unit has an input end connected to the main hydraulic oil tank and the auxiliary hydraulic oil tank, and an output end connected to the first end of the execution unit, and is used to suck hydraulic oil from the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank to provide working oil for the execution unit; The hydraulic oil return control unit is connected to the second end of the execution unit and is used to adjust the direction of the return oil of the execution unit so that the return oil flows to the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank; The anti-cavitation control unit is connected to the output end of the hydraulic oil supply unit and is used to control the hydraulic oil in the auxiliary hydraulic oil tank to enter the hydraulic oil supply unit; The control unit is connected to the hydraulic oil return control unit and the anti-cavitation control unit, and is used to control the working states of the hydraulic oil return control unit and the anti-cavitation control unit.

2. The system according to claim 1, wherein: The hydraulic oil supply unit includes: a power unit, a plunger hydraulic main pump and a pilot gear pump; The power device is connected to the driving end of the plunger hydraulic main pump and the driving end of the pilot gear pump, and is used to provide hydraulic energy to the plunger hydraulic main pump and the pilot gear pump; The plunger hydraulic main pump has an input end connected to the main hydraulic oil tank and the auxiliary hydraulic oil tank, and an output end connected to the execution unit, and is used to suck hydraulic oil from the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, to provide working oil for the execution unit; The pilot gear pump has an input end connected to the main hydraulic oil tank and the auxiliary hydraulic oil tank, and an output end connected to the anti-cavitation control unit, and is used to suck hydraulic oil from the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank to provide pilot control oil for the anti-cavitation control unit.

3. The system according to claim 2, characterized in that The hydraulic oil return control unit includes: a back pressure valve, a bypass valve, The back pressure valve has a first end connected to the execution unit and a second end connected to the main hydraulic oil tank, and is configured to open when the current pressure of the back pressure valve reaches a first preset pressure, so that the return oil flows to the main hydraulic oil tank; The bypass valve has a first end connected to the execution unit and a second end connected to the main hydraulic oil tank and the auxiliary hydraulic oil tank, and is used to open when the current pressure of the back pressure valve reaches a second preset pressure, allowing the return oil to flow to the main hydraulic oil tank and the auxiliary hydraulic oil tank.

4. The system according to claim 3, characterized in that The system further comprises: a first control valve and a second control valve, and the anti-cavitation control unit comprises: a proportional control solenoid valve; The first control valve has a first end connected to the input end of the auxiliary hydraulic oil tank and a second end connected to the second end of the bypass valve, and is used to adjust the hydraulic oil input amount of the auxiliary hydraulic oil tank; The second control valve has a first end connected to the output end of the auxiliary hydraulic oil tank and a second end connected to the plunger hydraulic main pump and the pilot gear pump, and is used to adjust the hydraulic oil output of the auxiliary hydraulic oil tank; The proportional control solenoid valve has a control end connected to the control unit, an input end connected to the pilot gear pump, and an output end connected to the driving end of the first control valve and the driving end of the second control valve. It is used to open under the control instruction generated by the control unit based on the oil suction condition of the hydraulic oil supply unit, and output the pilot control oil to the first control valve and the second control valve so that the first control valve and the second control valve are opened synchronously.

5. The system according to any one of claims 2 to 4, characterized in that The system further comprises: an oil level sensor and an oil suction pressure sensor; The oil level sensor is disposed on the auxiliary hydraulic oil tank and is used to detect the oil level of the auxiliary hydraulic oil tank; The oil suction pressure sensor is disposed in the oil suction pipeline between the plunger hydraulic main pump and the main hydraulic oil tank and the auxiliary hydraulic oil tank, and is used to detect the oil suction pressure of the oil suction pipeline.

6. A hydraulic pump control method, characterized in that: The hydraulic pump control system includes a control unit, a hydraulic oil supply unit, an execution unit, a hydraulic oil return control unit, a main hydraulic oil tank, a secondary hydraulic oil tank, and an anti-cavitation control unit. The control method is applied to the control unit, and the method includes: Acquiring the hydraulic oil demand of the execution unit, and controlling the hydraulic oil supply unit to suck hydraulic oil according to the hydraulic oil demand to provide working oil for the execution unit; controlling the working state of the hydraulic oil return control unit according to the oil return status of the execution unit so that the return oil of the execution unit flows to the main hydraulic oil tank or the main hydraulic oil tank and the auxiliary hydraulic oil tank; The working state of the anti-cavitation control unit is controlled according to the oil suction condition of the hydraulic oil supply unit, so that the hydraulic oil in the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, enters the hydraulic oil supply unit.

7. The method according to claim 6, characterized in that The hydraulic oil return control unit includes: a back pressure valve and a bypass valve; Controlling the working state of the hydraulic oil return control unit according to the oil return status of the execution unit so that the return oil of the execution unit flows to the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, including: Obtaining a current pressure of the back pressure valve, and determining whether the current pressure is higher than a first preset pressure or a second preset pressure, the first preset pressure being lower than the second preset pressure; If the current pressure is higher than the first preset pressure, controlling the back pressure valve to open so that the return oil flows to the main hydraulic oil tank; If the current pressure is higher than the second preset pressure, when the back pressure valve is opened, the bypass valve is controlled to open so that the return oil flows to the main hydraulic oil tank and the auxiliary hydraulic oil tank.

8. The method according to claim 6, characterized in that The hydraulic pump control system further includes: a first control valve and a second control valve; the anti-cavitation control unit includes: a proportional control solenoid valve; and an oil suction pressure sensor is disposed on the hydraulic oil supply unit and the oil suction pipeline between the main hydraulic oil tank and the auxiliary hydraulic oil tank; Controlling the working state of the anti-cavitation control unit according to the oil suction condition of the hydraulic oil supply unit so that the hydraulic oil in the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank, enters the hydraulic oil supply unit, comprising: obtaining an oil suction pressure of the oil suction pipeline, and determining whether the oil suction pressure is lower than a third preset pressure or a fourth preset pressure, wherein the third preset pressure is greater than the fourth preset pressure; If the oil suction pressure is not lower than the third preset pressure, controlling the proportional control solenoid valve to close so that the hydraulic oil in the main hydraulic oil tank enters the hydraulic oil supply unit; If the oil suction pressure is lower than the third preset pressure, the current opening of the proportional control solenoid valve is controlled according to the oil suction pressure, so that the first control valve and the second control valve are opened synchronously, the return oil enters the auxiliary hydraulic oil tank according to the preset flow rate, and the hydraulic oil in the auxiliary hydraulic oil tank enters the hydraulic oil supply unit according to the preset flow rate; If the oil suction pressure is lower than the fourth preset pressure, the proportional control solenoid valve is controlled to open to the maximum opening, so that the first control valve and the second control valve are synchronously opened to the maximum opening, the return oil enters the auxiliary hydraulic oil tank at the maximum flow rate, and the hydraulic oil in the auxiliary hydraulic oil tank enters the hydraulic oil supply unit at the maximum flow rate.

9. The method according to claim 8, characterized in that The auxiliary hydraulic oil tank is equipped with an oil level sensor. In the process of controlling the working state of the anti-cavitation control unit according to the oil suction condition of the hydraulic oil supply unit so that the hydraulic oil of the main hydraulic oil tank, or the main hydraulic oil tank and the auxiliary hydraulic oil tank enters the hydraulic oil supply unit, the method further includes: Obtaining the real-time oil level of the auxiliary hydraulic oil tank, and determining whether the real-time oil level has changed, and if so, generating a first alarm signal; It is determined whether the oil suction pressure is lower than a fifth preset pressure, and the fifth preset pressure is lower than the fourth preset pressure. If the fifth preset pressure is lower than the fifth preset pressure, the control strategy is adjusted and a second alarm signal is generated.

10. An engineering machinery equipment, characterized in that: A hydraulic pump control system comprising the hydraulic pump control system according to any one of claims 5 to 9.

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