Workload simulation device and method for constant-pressure variable pump

Abstract

The invention discloses a constant-pressure variable pump working load simulation device and method. The constant-pressure variable pump working load simulation device comprises an oil tank, a tested constant-pressure variable pump, a driving motor, a controller, a flow sensor I, a proportional throttle valve, a pressure sensor I and a pressure sensor II. An oil suction port of the tested constant-pressure variable pump is communicated with the oil tank through an oil suction pipeline; a pressure sensor II is arranged on the oil suction pipeline; the oil outlet pipeline is sequentially provided with a pressure sensor I, a flow sensor I and a proportional throttle valve; oil is sucked in through the oil suction port and extruded out of the oil outlet, the oil outlet is communicated with the oil tank through the oil outlet pipeline to form an oil circulation closed loop, and working pressure is formed. The controller is used for receiving and processing the data information and converting the data information into a command signal, and the controller sends the command signal to the proportional throttle valve; the proportional throttle valve changes the load flow of the tested constant-pressure variable pump in real time by adjusting the opening degree of a valve port of the proportional throttle valve according to the command signal. The performance test and the durability test of the constant-pressure variable pump under the actual load working condition can be simulated.

Description

Technical Field

[0001] The invention belongs to the technical field of hydraulic component testing, and in particular relates to a constant pressure variable pump working load simulation device and method. Background Art

[0002] According to whether the displacement is variable, hydraulic pumps are divided into fixed displacement pumps and variable displacement pumps. Constant pressure variable displacement is one of the variable control methods of variable pumps, and constant pressure variable displacement pumps are a type of variable displacement pumps. When the system pressure reaches the set pressure, the constant pressure variable displacement pump will automatically reduce the displacement to keep the output pressure unchanged. The outlet pressure of the constant pressure variable displacement pump is the feedback signal of the variable control. When the outlet pressure does not match the set pressure, the displacement of the pump can be adjusted through the position control of the variable mechanism, so that the output flow of the pump is always adapted to the load flow, and the outlet pressure of the pump is maintained at the set value, that is, the constant pressure variable displacement pump has the function of keeping the outlet pressure unchanged within its capacity. Constant pressure variable displacement pumps are often used in situations where the load flow changes greatly or there are high requirements for system efficiency.

[0003] When testing the performance of a constant pressure variable pump, it is usually only carried out under several specific load flows or working conditions. The load of the variable pump only needs to be slowly controlled or switched between several specific working conditions. Such tests can only be used to test the basic characteristics of a constant pressure variable pump, and because the load flow selected for the test and the load of the variable pump during actual operation have a large deviation, it is impossible to simulate its working conditions under real load conditions. In addition, when conducting durability tests on variable pumps, usually only one or several specific loads are specified, which are quite different from the actual working conditions of the variable pump, and the test results are not very reliable. Summary of the invention

[0004] In view of this, the constant-pressure variable pump working load simulation device and method provided by the present invention can adjust the load flow of the constant-pressure variable pump in real time to simulate the performance test and durability test of the constant-pressure variable pump under actual load conditions without the need for an actuator and its working object, and the experimental results are highly credible.

[0005] The present invention is realized by the following technical scheme: a constant pressure variable pump working load simulation device, comprising an oil tank, a tested constant pressure variable pump, a driving motor, a controller, a flow sensor I, a proportional throttle valve, a pressure sensor I and a pressure sensor II; the oil suction port of the tested constant pressure variable pump is connected to the oil tank through an oil suction pipeline, and a pressure sensor II is arranged on the oil suction pipeline; the oil outlet pipeline is provided with a pressure sensor I, a flow sensor I and a proportional throttle valve in sequence; the tested constant pressure variable pump rotates under the drive of the driving motor, and the oil in the oil tank is sucked in through the oil suction port and squeezed out from the oil outlet of the tested constant pressure variable pump, and the oil outlet is connected through the oil outlet pipe The oil flow path is connected to the proportional throttle valve and then finally connected back to the oil tank to form an oil circulation closed loop to form a working pressure; the pressure sensor Ⅰ, the flow sensor Ⅰ and the pressure sensor Ⅱ are respectively used to detect the pressure information Ⅰ of the oil outlet, the flow information Ⅰ of the oil outlet and the pressure information Ⅱ of the oil suction port, and all send the pressure information Ⅰ, flow information Ⅰ and pressure information Ⅱ to the controller; the controller is used to receive and process data information and convert it into a command signal, and the controller sends a command signal to the proportional throttle valve; the proportional throttle valve changes the load flow of the tested constant pressure variable pump in real time by adjusting its own valve port opening according to the command signal.

[0006] Furthermore, it also includes a data acquisition device, a pressure sensor III and a flow sensor II; the flow sensor II is connected in series to the front end of the actuator in the actual working system, and the pressure sensor III is arranged on the oil outlet pipeline of the constant pressure variable pump in the actual working system; the data acquisition device is used to receive the pressure information III sent by the pressure sensor III and the flow information II sent by the flow sensor II, and form an actual working load curve set; the actual working load curve set is input into the controller, and the controller is used to convert the flow change curve in the actual working load curve set into a command signal of the proportional throttle valve; the controller is also used to compare the flow information I with the flow change curve, and convert the difference into a command signal.

[0007] Furthermore, the tested constant-pressure variable pump is provided with an oil leakage port, which is connected to the oil tank through an oil leakage pipeline, on which a pressure sensor IV and a flow sensor III are sequentially provided; the pressure sensor IV and the flow sensor III are respectively used to detect the pressure information IV and flow information III of the oil leakage port of the tested constant-pressure variable pump, and the pressure sensor IV sends the pressure information IV to the controller.

[0008] Furthermore, a temperature sensor is provided on the oil outlet pipeline for detecting the working temperature of the oil and sending the temperature information to the controller; the oil tank is connected with the cooling pump and the radiator in sequence for cooling and dissipating the heat of the oil.

[0009] Furthermore, a safety relief valve is provided on the oil outlet pipeline of the tested constant pressure variable pump.

[0010] A method for simulating the working load of a constant pressure variable displacement pump, using the above simulation device, is used as follows:

[0011] Turn on the drive motor, and the constant-pressure variable pump under the drive of the drive motor establishes the required oil pressure in the simulation device and starts the simulation test; the pressure sensor Ⅰ, flow sensor Ⅰ, and pressure sensor Ⅱ send the detected pressure information Ⅰ, flow information Ⅰ, and pressure information Ⅱ to the controller; after receiving the above data information, the controller processes the data information and converts it into a corresponding command signal, and the controller sends the command signal to the proportional throttle valve; after receiving the controller command signal, the proportional throttle valve adjusts its own valve opening in real time to change the load flow of the constant-pressure variable pump under test; the simulation test records the data information received by the controller and the speed change data of the constant-pressure variable pump under test to complete the simulation test.

[0012] Furthermore, before starting the drive motor, the flow sensor II is connected in series to the front end of the actuator in the actual working system, and the pressure sensor III is installed on the oil outlet pipeline of the constant pressure variable pump in the actual working system; a data acquisition device is used to receive the pressure information III sent by the pressure sensor III and the flow information II sent by the flow sensor II, and the data acquisition device processes the above information and forms an actual working load curve set; the actual working load curve set of the constant pressure variable pump in the actual working system is input into the controller as a target signal; the controller converts the flow change curve in the actual working load curve set into a command signal and sends it to the proportional throttle valve, and at the same time, the controller compares the real-time received flow information I with the flow change curve, and converts the difference into a command signal and sends it to the proportional throttle valve; the proportional throttle valve adjusts its own valve opening according to the difference.

[0013] Furthermore, a safety relief valve is provided on the oil outlet pipeline. Before the drive motor is turned on, the relief pressure of the safety relief valve is set to 115% of the set pressure of the tested constant pressure variable pump.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] 1. The present invention adopts a proportional throttle valve as the load actuator of the constant-pressure variable pump under test. There is no need to build an actuator and its working object. It can realize the performance test and durability test of the constant-pressure variable pump under different load flow rates under simulated actual working conditions, thereby improving the convenience of the variable pump test work and the credibility of life prediction.

[0016] 2. The present invention utilizes flow sensors and pressure sensors as parameter acquisition elements for actual working load testing and load simulation of constant-pressure variable pumps, obtains the actual working load curve of the constant-pressure variable pump in the actual working system as the target signal, and utilizes closed-loop feedback control to realize the simulation of the working load by the test load, so that the flow curve of the tested constant-pressure variable pump in the entire simulation process can infinitely approach the real flow change curve in the actual working process.

[0017] 3. The present invention can collect the leakage port pressure and leakage flow data, and send the data information to the controller, thereby achieving the purpose of detecting the working status of the oil pump.

[0018] 4. The present invention is equipped with a temperature sensor for detecting the oil temperature, and is also provided with a cooling pump and a radiator to ensure the working temperature of the entire simulation device in real time. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is the schematic diagram of the overall assembly of the working load simulation device of the constant pressure variable pump under test.

[0020] Figure 2 Schematic diagram of the collection process of the actual working load curve set.

[0021] Figure 3 It is the working load simulation test principle of the constant pressure variable pump under test.

[0022] Among them, 1-safety relief valve, 2-controller, 3-flow sensor I, 4-proportional throttle valve, 5-temperature sensor, 6-cooling pump, 7-radiator, 8-oil tank, 9-flow sensor III, 10-pressure sensor I, 11-tested constant pressure variable pump, 12-drive motor, 13-pressure sensor IV, 14-pressure sensor II, 15-data acquisition equipment, 16-actuator, 17-operating object, 18-actual working load curve set, 19-actual working system, 20-pressure sensor III, 21-constant pressure variable pump, 22-flow sensor II. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0024] The present invention provides a constant pressure variable pump working load simulation device, such as Figure 1 As shown, the simulation device includes an oil tank 8, a constant pressure variable pump 11 under test, a drive motor 12, a controller 2, a flow sensor Ⅰ3, a proportional throttle valve 4, a pressure sensor Ⅰ10 and a pressure sensor Ⅱ14.

[0025] The oil tank 8 stores the oil used for the simulation test. The oil suction port of the tested constant pressure variable pump 11 is connected to the oil tank 8 through the oil suction pipeline. The oil suction pipeline is provided with a pressure sensor II 14; the oil outlet pipeline is provided with a pressure sensor I 10, a flow sensor I 3, and a proportional throttle valve 4 in sequence; the tested constant pressure variable pump 11 rotates under the drive of the drive motor 12, sucks the oil in the oil tank 8 through the oil suction port and squeezes it out from the oil outlet of the tested constant pressure variable pump 11, and the oil outlet is connected to the oil tank 8 through the oil outlet pipeline. The oil tank 8, the oil suction pipeline, the tested constant pressure variable pump 11, the oil outlet pipeline and the proportional throttle valve 4 form an oil circulation closed loop to form a working pressure. A safety relief valve 1 can also be provided on the oil outlet pipeline of the tested constant pressure variable pump 11, which can be used to unload the load when the simulation device encounters a pressure shock to ensure safety.

[0026] Pressure sensor Ⅰ10, flow sensor Ⅰ3 and pressure sensor Ⅱ14 are used to detect the pressure information Ⅰ of the oil outlet, the flow information Ⅰ of the oil outlet and the pressure information Ⅱ of the oil suction port respectively, and all send the pressure information Ⅰ, flow information Ⅰ and pressure information Ⅱ to the controller 2; the controller 2 is used to receive and process data information, and convert the data information into a command signal, and the controller sends a command signal to the proportional throttle valve 4; the proportional throttle valve 4 changes the load flow of the tested constant pressure variable pump 11 in real time by adjusting its own valve opening according to the command signal. The proportional throttle valve 4 is used to simulate the load actuator of the tested constant pressure variable pump 11, and the closed-loop feedback control is used to realize the simulation of the test load to the working load, that is, there is no need to build an actuator and an actuator working object, and the complete hydraulic system can be built, which saves time and effort and greatly saves costs.

[0027] like Figure 2 As shown, the simulation device also includes a data acquisition device 15, a pressure sensor III 20 and a flow sensor II 22, which are used to construct an actual working load curve set 18 in an actual working system 19. The actual working system 19 includes a constant pressure variable pump 21, an actuator 16 and an execution object 17 connected to the pipeline in sequence. The flow sensor II 22 is connected in series to the front end of the actuator 16 in the actual working system 19, and the pressure sensor III 20 is arranged on the oil outlet pipeline of the constant pressure variable pump 21 in the actual working system 19. The data acquisition device 15 is used to receive and record the pressure information III sent by the pressure sensor III 20 and the flow information II sent by the flow sensor II 22, and form an actual working load curve set 18, which includes a pressure-time history curve and a flow-time history curve of the oil outlet of the constant pressure variable pump. A temperature sensor II can also be arranged on the oil outlet pipeline of the constant pressure variable pump 21 to detect the temperature change of the actual working system and send the temperature information II to the data acquisition device 15.

[0028] The actual working load curve set 18 is input into the controller 2, and the controller 2 is used to convert the flow change curve in the actual working load curve set 18 into a command signal and send it to the proportional throttle valve 4. The controller 2 is also used to compare the flow information I with the flow change curve and convert the difference into a command signal.

[0029] As a further improvement, the tested constant pressure variable pump 11 is provided with a leakage oil port, which is connected to the oil tank 8 through an oil leakage pipeline. The oil leakage pipeline is provided with a pressure sensor IV13 and a flow sensor III9 in sequence. The pressure sensor IV13 and the flow sensor III9 are used to detect the pressure information IV and the flow information III of the leakage oil port of the tested constant pressure variable pump 11 respectively. The pressure sensor IV13 sends the pressure information IV to the controller 2. Through the leakage port pressure information IV and the leakage flow information III, the working state of the tested constant pressure variable pump 11 can be detected. When the efficiency of the tested constant pressure variable pump 11 is reduced or abnormal wear occurs, the leakage flow will change significantly.

[0030] As a further improvement, a temperature sensor 5 is also provided on the oil outlet pipeline of the tested constant pressure variable pump 11, which is used to detect the working temperature of the oil and send the temperature information to the controller 2; the oil tank 8 is connected with the cooling pump 6 and the radiator 7 in sequence, and the cooling pump 6 is connected to an independent cooling water circulation system or an air cooling system. When the set temperature is exceeded, the cooling pump 6 and the radiator 7 are turned on to cool the oil in the oil tank to ensure that the oil temperature is within the allowable range of the constant pressure variable pump 11 of the test piece.

[0031] A method for simulating the working load of a constant pressure variable displacement pump, using the above simulation device, is used as follows:

[0032] Before turning on the drive motor 12, the simulation device sets the relief pressure of the safety relief valve 1 to 115% of the set pressure of the constant pressure variable pump 11 under test. When the drive motor 12 is turned on, the constant pressure variable pump 11 under test builds up the required oil pressure in the simulation device under the drive of the drive motor 12, and the oil flows through the flow sensor Ⅰ3 and the proportional throttle valve 4 in sequence, and finally flows back to the oil tank 8, and the simulation test begins.

[0033] The pressure sensor Ⅰ10, the flow sensor Ⅰ3, and the pressure sensor Ⅱ14 respectively detect the pressure information Ⅰ of the oil outlet, the flow information Ⅰ of the oil outlet, and the pressure information Ⅱ of the oil suction port, and send the detected pressure information Ⅰ, flow information Ⅰ, and pressure information Ⅱ to the controller 2; the pressure sensor Ⅳ13 and the flow sensor Ⅲ9 respectively detect the pressure information Ⅳ and flow information Ⅲ of the leakage oil port of the tested constant pressure variable pump 11, and the pressure sensor Ⅳ13 sends the pressure information Ⅳ to the controller 2.

[0034] After receiving the above information, the controller 2 processes the information and converts it into a corresponding command signal, and the controller 2 sends the command signal to the proportional throttle valve 4. After receiving the command signal from the controller 2, the proportional throttle valve 4 adjusts its valve opening in real time and changes the load flow of the constant pressure variable pump 11 under test in real time; the simulation test records the data information received by the controller 2 under different working conditions and the speed change data of the constant pressure variable pump 11 under test that changes with the load flow, and completes the simulation test.

[0035] like Figure 3 As shown, in a specific implementation, if the tested constant-pressure variable pump 11 needs to simulate the real working load of the constant-pressure variable pump 21, it is necessary to collect the actual working load curve set 18 of the constant-pressure variable pump 21 in the actual working system 19. The collection process of the actual working load curve set 18 needs to cover the typical working profile of the actual working system 19, that is, the actual working load curve set 18 of the constant-pressure variable pump 21 under different typical working conditions. The collection method is as follows:

[0036] The flow sensor II 22 is connected in series to the front end of the actuator 16 in the actual working system 19, and the pressure sensor III 20 is installed on the oil outlet pipeline of the constant pressure variable pump 21 in the actual working system 19; the data acquisition device 15 is used to receive the pressure information III sent by the pressure sensor III 20 and the flow information II sent by the flow sensor II 22, and the data acquisition device 15 processes the above information and forms an actual working load curve set 18.

[0037] Before the constant pressure variable pump 11 is subjected to the load simulation experiment, the actual working load curve set 18 formed by the data acquisition device 15 is input into the controller 2 as the target signal. After the simulation starts, the controller 2 converts the flow change curve in the actual working load curve set 18 into a command signal and sends it to the proportional throttle valve 4, and the proportional throttle valve 4 starts to work.

[0038] At the same time, the controller 2 compares the real-time received flow information I with the flow change curve in the actual working load curve set 18, and converts the difference into a command signal, which is received by the proportional throttle valve 4, and the proportional throttle valve 4 then adjusts its valve opening according to the difference, so that the flow through the proportional throttle valve 4 infinitely approaches the target flow, that is, infinitely approaches the flow in the actual working process of the constant pressure variable pump 21. The proportional throttle valve 4 is used to simulate the working load flow change of the constant pressure variable pump 21, and the flow sensor I3 is used to measure the actual output flow of the tested constant pressure variable pump 11. The controller 2 calculates the real-time flow of the tested constant pressure variable pump 11 measured by the flow sensor I3 and compares it with the actual output flow of the constant pressure variable pump 21 in the actual working process, and outputs the difference to the proportional throttle valve 4 to realize closed-loop feedback control; so that the flow curve of the tested constant pressure variable pump 11 in the entire simulation process can infinitely approach the real flow change curve in the actual working process, and achieve the purpose of simulating the working load of the constant pressure variable pump 21.

[0039] The working load simulation device and method provided by the present invention can truly simulate the working load of the constant-pressure variable pump 21, and can perform simulation tests of the working load of the constant-pressure variable pump 21 and durability tests under real working conditions without an actuator.

[0040] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A constant pressure variable pump working load simulation device, characterized in that: It includes an oil tank, a constant pressure variable pump to be tested, a driving motor, a controller, a flow sensor I, a proportional throttle valve, a pressure sensor I and a pressure sensor II; The oil suction port of the tested constant pressure variable pump is connected to the oil tank through the oil suction pipeline, and a pressure sensor II is arranged on the oil suction pipeline; the oil outlet pipeline is provided with a pressure sensor I, a flow sensor I, and a proportional throttle valve in sequence; the tested constant pressure variable pump rotates under the drive of the driving motor, sucks the oil in the oil tank through the oil suction port and squeezes it out from the oil outlet of the tested constant pressure variable pump, and the oil outlet is connected to the proportional throttle valve through the oil outlet pipeline and then connected to the oil tank to form an oil circulation closed loop, forming a working pressure; The pressure sensor I, the flow sensor I and the pressure sensor II are used to detect the pressure information I of the oil outlet, the flow information I of the oil outlet and the pressure information II of the oil suction port respectively, and all send the pressure information I, the flow information I and the pressure information II to the controller; The controller is used to receive and process data information and convert it into command signals. The controller sends command signals to the proportional throttle valve; the proportional throttle valve changes the load flow of the tested constant pressure variable pump in real time by adjusting its own valve opening according to the command signal.

2. The constant pressure variable pump working load simulation device according to claim 1, characterized in that: It also includes data acquisition equipment, pressure sensor III and flow sensor II; The flow sensor II is connected in series to the front end of the actuator in the actual working system, and the pressure sensor III is arranged on the oil outlet pipeline of the constant pressure variable pump in the actual working system; the data acquisition device is used to receive the pressure information III sent by the pressure sensor III and the flow information II sent by the flow sensor II, and form an actual working load curve set; The actual working load curve set is input into the controller, and the controller is used to convert the flow change curve in the actual working load curve set into a command signal; the controller is also used to compare the flow information I with the flow change curve, and convert the difference into a command signal.

3. The constant pressure variable pump working load simulation device according to claim 2, characterized in that: The tested constant pressure variable pump is provided with an oil leakage port, which is connected to the oil tank through an oil leakage pipeline. A pressure sensor IV and a flow sensor III are arranged on the oil leakage pipeline in sequence; the pressure sensor IV and the flow sensor III are used to detect the pressure information IV and the flow information III of the oil leakage port of the tested constant pressure variable pump respectively, and the pressure sensor IV sends the pressure information IV to the controller.

4. The constant pressure variable pump working load simulation device according to claim 3, characterized in that: A temperature sensor is also provided on the oil outlet pipeline to detect the working temperature of the oil and send the temperature information to the controller; the oil tank is connected to the cooling pump and the radiator in sequence for cooling and dissipating the heat of the oil.

5. The constant pressure variable pump working load simulation device according to any one of claims 1 to 4, characterized in that: A safety relief valve is installed on the oil outlet pipeline of the tested constant pressure variable pump.

6. A method for simulating the working load of a constant pressure variable displacement pump, characterized in that: The simulation device according to any one of claims 1 to 5 is used as follows: Turn on the drive motor, and the constant pressure variable pump under test builds up the required oil pressure in the simulation device under the drive of the drive motor, and starts the simulation test; The pressure sensor I, the flow sensor I, and the pressure sensor II send the detected pressure information I, flow information I, and pressure information II to the controller; After receiving the above data information, the controller processes the data information and converts it into a corresponding command signal, and the controller sends the command signal to the proportional throttle valve; After receiving the controller command signal, the proportional throttle valve adjusts its valve opening in real time to change the load flow of the tested constant pressure variable pump; The simulation test records the data information received by the controller and the speed change data of the constant pressure variable pump under test throughout the process to complete the simulation test.

7. The method for simulating the working load of a constant pressure variable displacement pump according to claim 6, characterized in that: Before starting the drive motor, connect the flow sensor II in series to the front end of the actuator in the actual working system, and install the pressure sensor III on the oil outlet pipeline of the constant pressure variable pump in the actual working system; use a data acquisition device to receive the pressure information III sent by the pressure sensor III and the flow information II sent by the flow sensor II, and the data acquisition device processes the above information and forms an actual working load curve set; An actual working load curve set of a constant pressure variable displacement pump in an actual working system is input into a controller as a target signal; The controller converts the flow change curve in the actual working load curve set into a command signal and sends it to the proportional throttle valve. At the same time, the controller compares the real-time received flow information I with the flow change curve, and converts the difference into a command signal and sends it to the proportional throttle valve. The proportional throttle valve adjusts its valve opening according to the difference.

8. The method for simulating the working load of a constant pressure variable displacement pump as described in claims 6-7, characterized in that: A safety relief valve is also provided on the oil outlet pipeline. Before starting the drive motor, the relief pressure of the safety relief valve is set to 115% of the set pressure of the tested constant pressure variable pump.

Images