A test tool for electric proportional pressure combination valve for wet clutch control of agricultural machinery

Abstract

The utility model relates to the technical field of agricultural machinery, and discloses a testing tool for an electric proportional pressure combination valve for wet clutch control of agricultural machinery, comprising a gear pump, a motor driving the gear pump, an oil supply pipeline connected to the gear pump, a clutch equivalent pressure chamber for connecting the electric proportional pressure combination valve, a pressure sensor, and a proportional electromagnet control unit. The utility model has the following advantages and effects: the utility model is specially used for an electric proportional pressure combination valve for wet clutch control of agricultural machinery, and can complete system tests of dynamic and static performance such as steady-state pressure control characteristic test, steady-state load characteristic test, temperature drift test, withstand voltage test, step response test, frequency response test, and durability test.

Description

Technical Field

[0001] The utility model relates to the technical field of agricultural machinery, in particular to a testing tool for an electric proportional pressure combination valve for wet clutch control of agricultural machinery. Background Art

[0002] The wet clutch is a clutch cooled by oil. The cooling oil does not protect the friction plate, but makes the power transmission smooth and gentle. The advantages are long service life and low failure rate. The wet clutch control mainly adopts hydraulic buffer valve control, electric proportional pressure valve control and pulse width modulation high-speed switch valve control. In the field of agricultural machinery, the wet clutch control for agricultural machinery mainly adopts hydraulic buffer valve control and electric proportional pressure combination valve control.

[0003] In the prior art, except for the proportional servo valve, the proportional valves used in engineering projects on the market are limited by cost and application scenarios, and only static characteristics of the static PI curve are tested, and there is no requirement for their dynamic characteristics. When the electric proportional servo valve is used in the wet clutch control of agricultural machinery, the power conversion of agricultural machinery needs to control the oil filling time of the first stage of the idle stroke stage, the sliding work of the second stage of the run-in stage, and the rapid engagement of the third stage. Therefore, effective testing methods are needed to test the dynamic and static characteristics of the proportional valve. In the current prior art, the agricultural machinery industry does not have professional tooling to test the dynamic and static performance of the electric proportional pressure combination valve for wet clutch control. Utility Model Content

[0004] The utility model aims to provide a testing tool for an electric proportional pressure combination valve for wet clutch control of agricultural machinery, which has the effect of being specially used for dynamic and static performance testing of the electric proportional pressure combination valve for wet clutch control of agricultural machinery.

[0005] The above-mentioned technical purpose of the utility model is achieved through the following technical scheme: a test tool for an electric proportional pressure combination valve for wet clutch control of agricultural machinery, including a gear pump, a motor driving the gear pump, an oil supply pipeline connected to the gear pump, a clutch equivalent pressure chamber for connecting the electric proportional pressure combination valve, a pressure sensor, and a proportional solenoid control unit.

[0006] The utility model is further configured as follows: the motor is a constant speed servo motor.

[0007] The utility model is further configured as follows: the clutch equivalent pressure chamber includes a forward equivalent pressure chamber and a backward equivalent pressure chamber.

[0008] The utility model is further configured as follows: the forward equivalent pressure chamber and the backward equivalent pressure chamber are both provided with exhaust holes.

[0009] The utility model is further configured as follows: it also includes a first connecting pipe and a second connecting pipe, the first connecting pipe is connected to the forward equivalent pressure chamber, and the second connecting pipe is connected to the backward equivalent pressure chamber.

[0010] The utility model is further configured as follows: the first connecting pipe is connected to a first branch pipe, the second connecting pipe is connected to a second branch pipe, and the number of the pressure sensors is two and they are respectively installed on the first branch pipe and the second branch pipe.

[0011] The utility model is further configured as follows: the first branch pipe is detachably connected to the first connecting pipe, and the second branch pipe is detachably connected to the second connecting pipe.

[0012] By adopting the above technical solution, the pressure sensors are respectively installed on the first branch pipe and the second branch pipe, which is convenient for installation, disassembly and replacement, and does not affect the proportional pressure combination valve and the forward equivalent pressure chamber and the backward equivalent pressure chamber.

[0013] The utility model is further configured as follows: the proportional solenoid control unit is used to send a proportional solenoid control signal to the proportional pressure combination valve.

[0014] The beneficial effects of the utility model are as follows: the utility model is specially used for the electric proportional pressure combination valve for wet clutch control of agricultural machinery, and can complete system tests of dynamic and static performance such as steady-state pressure control characteristic test, steady-state load characteristic test, temperature drift test, withstand voltage test, step response test, frequency response test, and durability test. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0016] Figure 1 It is a structural schematic diagram of the utility model.

[0017] Figure 2 It is a PI curve diagram in the steady-state pressure control characteristic test of the utility model.

[0018] Figure 3 It is a schematic diagram of steady-state load characteristics in a steady-state load characteristic test of the utility model.

[0019] Figure 4 It is a step response curve diagram of the step response test of the utility model.

[0020] Figure 5 It is a Bode diagram of the frequency response test of the utility model.

[0021] In the figure, 1. gear pump; 2. motor; 3. oil supply pipeline; 4. clutch equivalent pressure chamber; 41. forward equivalent pressure chamber; 42. reverse equivalent pressure chamber; 43. exhaust hole; 5. pressure sensor; 6. proportional solenoid control unit; 7. first connecting pipe; 71. first branch pipe; 8. second connecting pipe; 81. second branch pipe. DETAILED DESCRIPTION

[0022] The technical solution of the utility model will be described clearly and completely below in conjunction with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of them. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] A test fixture for an electric proportional pressure combination valve for wet clutch control of agricultural machinery, such as Figure 1 As shown, it includes a gear pump 1, a motor 2 driving the gear pump 1, an oil supply pipeline 3 connected to the gear pump 1, a clutch equivalent pressure chamber 4 for connecting to an electric proportional pressure combination valve, a pressure sensor 5, and a proportional electromagnet control unit 6. The motor 2 is a constant speed servo motor 2, and the clutch equivalent pressure chamber 4 includes a forward equivalent pressure chamber 41 and a backward equivalent pressure chamber 42. The forward equivalent pressure chamber 41 is connected to a first connecting pipe 7, and the backward equivalent pressure chamber 42 is connected to a second connecting pipe 8. The first connecting pipe 7 and the second connecting pipe 8 are both used to connect to the electric proportional pressure combination valve. The proportional electromagnet control unit 6 is used to send a proportional electromagnet control signal to the proportional pressure combination valve.

[0024] The first connecting pipe 7 is detachably connected to a first branch pipe 71 , the second connecting pipe 8 is detachably connected to a second branch pipe 81 , and there are two pressure sensors 5 , which are respectively installed on the first branch pipe 71 and the second branch pipe 81 .

[0025] Testing process:

[0026] 1. Static test

[0027] A. Steady-state pressure control characteristics test

[0028] Install the electric proportional pressure combination valve on the test bench, start the gear pump, and test the relationship between input current and steady-state pressure. The linearity, hysteresis, and repeatability are tested by measurement. The PI curve is as follows: Figure 2 shown.

[0029] B. Steady-state load characteristics test

[0030] Under a given set of control signals (30% (Io-I_d) + I_d, 70% (Io-I_d) + I_d, 100% (Io-I_d) + I_d), it was obtained by changing the gear pump speed and scanning continuously for one week.

[0031] C. Temperature drift test

[0032] The PI characteristics of the valve were tested at oil temperatures of 20°C, 40°C, and 80°C, and the control output was retrieved.

[0033] D. Withstand voltage test

[0034] Inject oil with a pressure 1.5 times the rated pressure into each oil port of the valve and maintain the pressure for 5 minutes.

[0035] 2. Step response test

[0036] I_d is the dead zone current of the combination valve, Io is the rated current, and Po is the rated pressure.

[0037] Install the electric pressure proportional combination valve and tooling on the test bench, start the gear pump, close the safety valve, and switch the front and rear reversing valves to the forward gear.

[0038] During the test, the control signal input to the valve is a step signal of 75% (Io-Id) + I_d rated current, and the input current signal is recovered through the recovery circuit. The test results are as follows Figure 4 shown.

[0039] The pressure signal of the pressure sensor is collected at the same time sequence.

[0040] 3. Frequency response test

[0041] Install the test fixture on the test bench, start the gear pump, close the safety valve, and switch the forward and backward direction to the forward gear.

[0042] The test amplitude ratio and phase angle difference are used to draw the Bode diagram. Figure 5 shown.

[0043] 4. Durability Test

[0044] Install the test fixture on the test bench, start the gear pump, close the safety valve, and switch the forward and backward direction to the forward gear.

[0045] Input a sine wave with a certain frequency and superimpose a current signal. After running the valve for a specified number of times, retest the valve performance.

Claims

1. A test tool for an electric proportional pressure combination valve for wet clutch control of agricultural machinery, characterized in that: The invention comprises a gear pump (1), a motor (2) for driving the gear pump (1), an oil supply pipeline (3) connected to the gear pump (1), a clutch equivalent pressure chamber (4) for connecting to an electric proportional pressure combination valve, a pressure sensor (5), and a proportional solenoid control unit (6).

2. The electric proportional pressure combination valve test tool for wet clutch control of agricultural machinery according to claim 1, characterized in that: The motor (2) is a constant speed servo motor (2).

3. The electric proportional pressure combination valve test tool for wet clutch control of agricultural machinery according to claim 1, characterized in that: The clutch equivalent pressure chamber (4) comprises a forward equivalent pressure chamber (41) and a backward equivalent pressure chamber (42).

4. The electric proportional pressure combination valve test tool for wet clutch control of agricultural machinery according to claim 3, characterized in that: The forward equivalent pressure chamber (41) and the backward equivalent pressure chamber (42) are both provided with exhaust holes (43).

5. The electric proportional pressure combination valve test tool for wet clutch control of agricultural machinery according to claim 3, characterized in that: It also comprises a first connecting pipe (7) and a second connecting pipe (8), wherein the first connecting pipe (7) is connected to the forward equivalent pressure chamber (41), and the second connecting pipe (8) is connected to the backward equivalent pressure chamber (42).

6. The electric proportional pressure combination valve test tool for wet clutch control of agricultural machinery according to claim 5, characterized in that: The first connecting pipe (7) is connected to a first branch pipe (71), the second connecting pipe (8) is connected to a second branch pipe (81), and there are two pressure sensors (5) which are respectively mounted on the first branch pipe (71) and the second branch pipe (81).

7. The electric proportional pressure combination valve test tool for wet clutch control of agricultural machinery according to claim 6, characterized in that: The first branch pipe (71) is detachably connected to the first connecting pipe (7), and the second branch pipe (81) is detachably connected to the second connecting pipe (8).

8. The electric proportional pressure combination valve test tool for wet clutch control of agricultural machinery according to claim 1, characterized in that: The proportional solenoid control unit (6) is used for sending a proportional solenoid control signal to the proportional pressure combination valve.

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