High-precision large-flow electro-hydraulic proportional valve and control method thereof

Abstract

The invention relates to the technical field of electro-hydraulic proportional valves, and discloses a high-precision large-flow electro-hydraulic proportional valve and a control method thereof.The high-precision large-flow electro-hydraulic proportional valve comprises a valve body, a valve element, a proportional electromagnet, a displacement sensor, an external controller and a drive circuit; the proportional electromagnet is fixedly arranged on the outer surface of the valve body, the displacement sensor is arranged in the valve body, a limiting hexagon facilitating limiting and rotating when the valve body is inserted in a threaded mode is fixedly arranged on the surface of the valve body, and a valve element displacement signal and a system pressure signal fed back by the displacement sensor are collected through the controller. The electro-hydraulic proportional valve has the advantages of being high in control precision, large in flow and high in response speed, collecting signals, filtering, amplifying and the like, eliminating noise interference, calculating control quantity according to a preset control algorithm such as PID (Proportion Integration Differentiation) control, converting the control quantity into PWM (Pulse Width Modulation) signals, driving the proportional electromagnet to act and controlling the valve core to displace at the same time, and meanwhile, the electro-hydraulic proportional valve has the advantages of being high in control precision, large in flow and high in response speed.

Description

Technical Field

[0001] The present invention relates to the technical field of electro-hydraulic proportional valves, and in particular to a high-precision and large-flow electro-hydraulic proportional valve and a control method thereof. Background Art

[0002] The electro-hydraulic proportional valve is a key component in the electro-hydraulic control system. Its performance directly affects the control accuracy and response speed of the system. With the continuous improvement of industrial automation, the performance requirements for electro-hydraulic proportional valves are getting higher and higher, especially in high-precision and large-flow applications, such as metallurgy, engineering machinery, ships and other fields. Traditional electro-hydraulic proportional valves have the following shortcomings: Low control accuracy: Traditional electro-hydraulic proportional valves mostly use analog control, which is easily affected by factors such as temperature drift and electromagnetic interference, and the control accuracy is difficult to guarantee.

[0003] Small flow rate: Due to structural limitations, traditional electro-hydraulic proportional valves are difficult to achieve large flow control.

[0004] Slow response speed: The dynamic response speed of traditional electro-hydraulic proportional valves is slow, which makes it difficult to meet the needs of high-speed and high-precision control.

[0005] To this end, the present invention provides a high-precision and large-flow electro-hydraulic proportional valve and a control method thereof. Summary of the invention

[0006] In order to make up for the deficiencies of the prior art, at least one technical problem raised in the background technology is solved.

[0007] The present invention provides a high-precision and large-flow electro-hydraulic proportional valve, comprising: Valve body, valve core, proportional solenoid, displacement sensor, external controller and drive circuit; The valve core is arranged at the end of the valve body, and the proportional electromagnet is fixedly arranged on the outer surface of the valve body, and the displacement sensor is arranged inside the valve body. The surface of the valve body is fixedly provided with a limit hexagon for facilitating the limiting and rotating of the valve body when the valve body is threadedly inserted, and the surface of the valve body is threadedly connected with a hexagonal nut for facilitating the installation of the proportional electromagnet; The proportional electromagnet adopts new magnetic materials and structural design to improve electromagnetic force output and increase flow rate. The controller adopts a digital signal processor or a microcontroller to achieve high-precision and high-speed digital control. The drive circuit adopts a PWM drive method to improve the response speed and control accuracy of the electromagnet.

[0008] By adopting the above technical solution, the electro-hydraulic proportional valve has the advantages of high control accuracy, large flow rate and fast response speed.

[0009] Preferably, a circuit connector for connecting to an external circuit is provided on the surface of the proportional electromagnet.

[0010] By adopting the above technical solution, a line connector is provided to facilitate electrical connection with an external controller via a cable.

[0011] Preferably, a positioning component for positioning the cable after being connected to the line connector is provided on the surface of the proportional electromagnet.

[0012] By adopting the above technical solution, the cable plugged and fixed on the line connector can be effectively limited and fixed by setting the positioning component.

[0013] Preferably, the positioning assembly comprises two L-shaped mounting rods fixedly mounted on the outer surface of the proportional electromagnet, and a positioning frame fixedly mounted on the ends of the L-shaped mounting rods, and two symmetrical positioning clamping plates are slidably mounted on the inner wall of the positioning frame.

[0014] By adopting the above technical solution, the cable can be effectively clamped by the two positioning clamps moving toward the middle at the same time.

[0015] Preferably, two semicircular positioning grooves corresponding to the cables are formed on the opposite surfaces of the two positioning clamps, and the inner walls of the four semicircular positioning grooves are fixedly provided with semicircular rubber anti-slip pads.

[0016] By adopting the above technical solution, the cable surface can be effectively protected under the action of two semicircular rubber anti-skid pads.

[0017] Preferably, the positioning assembly further comprises a connection box fixedly mounted on the surface of the positioning frame, and a plum blossom turntable rotatably mounted on the surface of the connection box for driving the two positioning clamping plates to move toward the middle simultaneously.

[0018] By adopting the above technical solution, the two positioning clamps can be moved toward the middle at the same time by rotating the plum blossom turntable.

[0019] Preferably, the inner wall of the positioning frame is rotatably provided with two symmetrical bidirectional threaded columns, and the surfaces of the two positioning clamping plates are provided with two threaded holes respectively threadedly connected to the outer surfaces of the two bidirectional threaded columns.

[0020] By adopting the above technical solution, the two positioning clamps can be driven to move toward the middle at the same time through the rotation of the bidirectional threaded column.

[0021] Preferably, one end of the two bidirectional threaded columns extends to the interior of the connection box, the inner wall of the connection box is rotatably provided with a rotating shaft extending to the outer surface of the connection box, and the plum blossom rotating disk is fixed to the end of the rotating shaft.

[0022] By adopting the above technical solution, the rotation of the plum blossom turntable can drive the rotation of the rotating shaft.

[0023] Preferably, a first transmission wheel is fixedly provided on the surface of the rotating shaft, and a second transmission wheel is fixedly provided on the end surfaces of the two bidirectional threaded columns. Two transmission belts are sleeved on the surface of the first transmission wheel, and the other ends of the two transmission belts are respectively sleeved on the surfaces of the two second transmission wheels. The first transmission wheel is synchronously connected with the two second transmission wheels through the two transmission belts.

[0024] By adopting the above technical solution, during the rotation of the shaft, the two bidirectional threaded columns can be driven to rotate synchronously at the same time under the action of the first transmission wheel, the transmission belt and the second transmission wheel.

[0025] On the other hand, the present application also provides a control method for a high-precision and large-flow electro-hydraulic proportional valve, comprising the following steps: S1, signal acquisition: the controller collects the valve core displacement signal and system pressure signal fed back by the displacement sensor; S2, signal processing: The controller filters and amplifies the collected signals to eliminate noise interference, uses a low-pass filter to filter out signals higher than 120 Hz, and uses a signal amplifier to amplify the signal by 30 times; S3, control algorithm: The controller calculates the control quantity according to the preset control algorithm PID control; S4, drive output: the controller converts the control quantity into a PWM signal, drives the proportional solenoid to operate, and controls the displacement of the valve core; S5. Closed-loop control: The controller adjusts the control amount in real time according to the valve core displacement signal fed back by the displacement sensor to achieve closed-loop control. In the closed-loop control, the actual displacement signal detected by the displacement sensor is compared with the preset target value in real time, and the deviation value is directly obtained by subtraction operation. The formula is: Deviation value = target setting value - actual displacement feedback value.

[0026] The beneficial effects of the present invention are: The high-precision, large-flow electro-hydraulic proportional valve and control method thereof described in the present invention collects the valve core displacement signal and system pressure signal fed back by the displacement sensor through a controller, and filters and amplifies the collected signals to eliminate noise interference. At the same time, the control amount is calculated according to a preset control algorithm (such as PID control), and the control amount is converted into a PWM signal to drive the proportional solenoid to operate and control the valve core displacement, so that the electro-hydraulic proportional valve has the advantages of high control accuracy, large flow and fast response speed.

[0027] The high-precision, large-flow electro-hydraulic proportional valve and control method thereof described in the present invention provide a positioning component so that, during the process of wiring and use after installation, after the cable and the line connector are plugged in, the plum blossom turntable can be rotated to drive the rotating shaft to rotate, and the rotation of the rotating shaft drives the first transmission wheel to rotate. The rotation of the first transmission wheel drives the two second transmission wheels to rotate simultaneously under the action of two transmission belts, thereby driving the two bidirectional threaded columns to rotate simultaneously. The rotation of the bidirectional threaded column drives the two positioning clamps to move toward the middle at the same time, so that the semicircular positioning grooves on the two positioning clamps effectively clamp and fix the two cables, thereby achieving effective positioning of the cables, avoiding the situation where the cables and the line connectors fall off due to inadvertent pulling from the outside, and ensuring the normal use of the electro-hydraulic proportional valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a three-dimensional structural schematic diagram of the present invention; Figure 2 It is a rear view structural schematic diagram of the present invention; Figure 3 It is a bottom-up structural schematic diagram of the present invention; Figure 4 It is a schematic diagram of the top view of the structure of the present invention; Figure 5 The present invention Figure 4 The enlarged structural diagram at A in the middle; Figure 6 It is a schematic diagram of the top cross-sectional structure of the connection box of the present invention; Figure 7 The present invention Figure 6 Enlarged structural diagram at B in the middle.

[0029] Description of reference numerals: 100, valve body; 101, limit hexagon; 102, hexagon nut; 200, valve core; 300, proportional solenoid; 400, line connector; 500, positioning assembly; 501, L-shaped mounting rod; 502, positioning frame; 503, positioning clamp; 504, semicircular rubber anti-skid pad; 505, connecting box; 506, plum blossom turntable; 507, bidirectional threaded column; 508, rotating shaft; 509, first transmission wheel; 5010, second transmission wheel; 5011, transmission belt. DETAILED DESCRIPTION

[0030] The subject matter described herein will now be discussed with reference to example embodiments. It should be understood that the discussion of these embodiments is only to enable those skilled in the art to better understand and implement the subject matter described herein, and the functions and arrangements of the elements discussed may be changed without departing from the scope of protection of the contents of this specification. Each example may omit, replace or add various processes or components as needed. In addition, the features described relative to some examples may also be combined in other examples. Example

[0031] The following is a further detailed description of the technical solution of the present invention in conjunction with the accompanying drawings and specific embodiments. Figures 1 to 7 , this application provides a high-precision, large-flow electro-hydraulic proportional valve, please refer to Figures 1 to 3 , including: a valve body 100, a valve core 200, a proportional electromagnet 300, a displacement sensor, an external controller and a drive circuit; the valve core 200 is arranged at the end of the valve body 100, and the proportional electromagnet 300 is fixedly arranged on the outer surface of the valve body 100, the displacement sensor is arranged inside the valve body 100, the surface of the valve body 100 is fixedly provided with a limit hexagon 101 for facilitating the limiting and rotation of the valve body 100 when the valve body 100 is threadedly inserted, the surface of the valve body 100 is provided with an external thread, and the surface of the valve body 100 is threadedly connected with a hexagonal nut 102 for facilitating the installation of the proportional electromagnet 300, the proportional electromagnet 300 adopts a new magnetic material, wherein the new magnetic material is N52 neodymium iron boron, which can improve the electromagnetic force output and increase the flow rate, the controller adopts a digital signal processor DSP or a microcontroller MCU to realize high-precision and high-speed digital control, and the drive circuit adopts a PWM drive mode to improve the response speed and control accuracy of the electromagnet.

[0032] Specifically, when installing the electro-hydraulic proportional valve, the valve core 200 can be inserted into the plug-in hole of the device, and the limiting hexagon 101 can be rotated with an external wrench, so that the bottom end of the valve body 100 of the electro-hydraulic proportional valve can be quickly installed with the plug-in hole of the device through the external thread, and then the proportional solenoid 300 is installed on the outer surface of the valve body 100 through the hexagonal nut 102, so as to realize the rapid installation of the electro-hydraulic proportional valve. In addition, the electro-hydraulic proportional valve has the advantages of high control accuracy, large flow rate and fast response speed during actual use.

[0033] Please refer to Figure 1 and Figure 2 A circuit connector 400 for connecting to an external circuit is provided on the surface of the proportional electromagnet 300 .

[0034] Specifically, when the electro-hydraulic proportional valve is wired, the cable can be fixed inside the line connector 400 by plugging it in, and then the line connector 400 is provided to facilitate electrical connection with an external controller through the cable.

[0035] Please refer to Figure 4 and Figure 5 A positioning assembly 500 for positioning the cable connected to the line connector 400 is disposed on the surface of the proportional electromagnet 300 .

[0036] Specifically, by providing the positioning assembly 500 , the cable plugged and fixed on the line connector 400 can be effectively limited and fixed.

[0037] Please refer to Figure 5 The positioning assembly 500 includes two L-shaped mounting rods 501 fixed on the outer surface of the proportional electromagnet 300, and a positioning frame 502 fixed on the ends of the L-shaped mounting rods 501. The inner wall of the positioning frame 502 is slidably provided with two symmetrical positioning clamps 503.

[0038] Specifically, the cable can be effectively clamped by the two positioning clamping plates 503 moving toward the middle at the same time.

[0039] Please refer to Figure 5 Two semicircular positioning grooves corresponding to the cables are formed on the opposite surfaces of the two positioning clamps 503 , and semicircular rubber anti-skid pads 504 are fixed on the inner walls of the four semicircular positioning grooves.

[0040] Specifically, the cable surface can be effectively protected under the action of the two semicircular rubber anti-skid pads 504 .

[0041] Please refer to Figure 5 The positioning assembly 500 also includes a connection box 505 fixed on the surface of the positioning frame 502, and a plum blossom turntable 506 rotatably arranged on the surface of the connection box 505 for driving the two positioning clamping plates 503 to move toward the middle at the same time.

[0042] Specifically, the two positioning clamping plates 503 can be moved toward the middle at the same time by rotating the plum blossom turntable 506 .

[0043] Please refer to Figure 6 and Figure 7 The inner wall of the positioning frame 502 is rotatably provided with two symmetrical bidirectional threaded columns 507 , and the surfaces of the two positioning clamping plates 503 are provided with two threaded holes respectively threadedly connected to the outer surfaces of the two bidirectional threaded columns 507 .

[0044] Specifically, the two positioning clamping plates 503 can be driven to move toward the middle at the same time by the rotation of the bidirectional threaded column 507 .

[0045] Please refer to Figure 6 and Figure 7One end of the two bidirectional threaded columns 507 extends to the inside of the connection box 505. The inner wall of the connection box 505 is rotatably provided with a rotating shaft 508 extending to the outer surface of the connection box 505, and the plum blossom rotating disk 506 is fixed to the end of the rotating shaft 508.

[0046] Specifically, the rotation of the plum blossom turntable 506 can drive the rotation shaft 508 to rotate.

[0047] Please refer to Figure 6 and Figure 7 A first transmission wheel 509 is fixedly provided on the surface of the rotating shaft 508, and second transmission wheels 5010 are fixedly provided on the end surfaces of the two bidirectional threaded columns 507. Two transmission belts 5011 are sleeved on the surface of the first transmission wheel 509, and the other ends of the two transmission belts 5011 are respectively sleeved on the surfaces of the two second transmission wheels 5010. The first transmission wheel 509 is synchronously connected with the two second transmission wheels 5010 through the two transmission belts 5011.

[0048] Specifically, during the rotation of the rotating shaft 508 , the two bidirectional threaded columns 507 can be driven to rotate synchronously at the same time under the action of the first transmission wheel 509 , the transmission belt 5011 and the second transmission wheel 5010 .

[0049] Among them, the present invention sets a positioning component 500, so that during the process of wiring and use of the electro-hydraulic proportional valve after installation, after the cable is plugged into the line connector 400, the plum blossom turntable 506 can be rotated to drive the rotating shaft 508 to rotate, and the rotation of the rotating shaft 508 drives the first transmission wheel 509 to rotate. The rotation of the first transmission wheel 509 drives the two second transmission wheels 5010 to rotate simultaneously under the action of two transmission belts 5011, thereby driving the two bidirectional threaded columns 507 to rotate simultaneously, and the rotation of the bidirectional threaded columns 507 drives the two positioning clamps 503 to move toward the middle at the same time, so that the semicircular positioning grooves on the two positioning clamps 503 effectively clamp and fix the two cables, thereby realizing effective cable limitation, avoiding the situation where the cable and the line connector 400 fall off due to inadvertent external pulling, and ensuring the normal use of the electro-hydraulic proportional valve.

[0050] On the other hand, the embodiment of the present application also provides a control method for a high-precision and large-flow electro-hydraulic proportional valve, comprising the following steps: S1, signal acquisition: the controller acquires the valve core 200 displacement signal and system pressure signal fed back by the displacement sensor; S2. Signal processing: The controller filters and amplifies the collected signals to eliminate noise interference, uses a low-pass filter to filter out signals higher than 120 Hz, and uses a signal amplifier to amplify the signal by 30 times.

[0051] S3, control algorithm: the controller calculates the control quantity according to the preset control algorithm such as PID control; When PID control is adopted, the PID coefficient adjustment rules are as follows: Adjust the proportional coefficient Kp. When debugging, first set a smaller Kp value, then gradually increase it until the system oscillates. Record the Kp value at this time, and then halve it as the initial value. Adjust the integral time constant Ti, initially set a larger Ti value, then gradually reduce it until the system oscillates, record the Ti value at this time, and multiply it by 1.2 to 1.5 times as the initial value; Adjust the differential time constant Td, starting from a smaller Td value and gradually increasing it until a suitable value is found to improve the dynamic performance of the system; S4, drive output: the controller converts the control quantity into a PWM signal, drives the proportional solenoid 300 to operate, and controls the displacement of the valve core 200; S5. Closed-loop control: The controller adjusts the control amount in real time according to the displacement signal of the valve core 200 fed back by the displacement sensor to realize closed-loop control. In the closed-loop control, the actual displacement signal detected by the displacement sensor is compared with the preset target value in real time, and the deviation value is directly obtained by subtraction operation. The formula is: Deviation value = target setting value - actual displacement feedback value.

[0052] Among them, the present invention collects the valve core 200 displacement signal and system pressure signal fed back by the displacement sensor through the controller, and filters and amplifies the collected signals to eliminate noise interference. At the same time, the control amount is calculated according to a preset control algorithm such as PID control, and the control amount is converted into a PWM signal to drive the proportional solenoid 300 to control the displacement of the valve core 200, so that the electro-hydraulic proportional valve has the advantages of high control accuracy, large flow rate and fast response speed.

[0053] Working principle: During the process of wiring and using the electro-hydraulic proportional valve after installation, after the cable is plugged into the line connector 400, the plum blossom turntable 506 can be rotated to drive the rotating shaft 508 to rotate, and the rotation of the rotating shaft 508 drives the first transmission wheel 509 to rotate. The rotation of the first transmission wheel 509 drives the two second transmission wheels 5010 to rotate simultaneously under the action of the two transmission belts 5011, thereby driving the two bidirectional threaded columns 507 to rotate simultaneously. The rotation of the bidirectional threaded column 507 drives the two positioning clamps 503 to move toward the middle at the same time, so that the semicircular positioning grooves on the two positioning clamps 503 can effectively clamp and fix the two cables, thereby The effective limit of the cable is achieved to avoid the cable and the line connector 400 from falling off due to inadvertent external pulling, thereby ensuring the normal use of the electro-hydraulic proportional valve. In addition, the electro-hydraulic proportional valve collects the valve core 200 displacement signal and the system pressure signal fed back by the displacement sensor through the controller, and filters and amplifies the collected signals to eliminate noise interference. At the same time, the control amount is calculated according to a preset control algorithm such as PID control, and the control amount is converted into a PWM signal to drive the proportional solenoid 300 to operate and control the displacement of the valve core 200, so that the electro-hydraulic proportional valve has the advantages of high control accuracy, large flow rate and fast response speed.

[0054] An example of the present specific implementation mode is described above, but the present embodiment is not limited to the above-mentioned specific implementation mode, which is merely illustrative and not restrictive. A person skilled in the art may make many forms inspired by the present embodiment, all of which are protected by the present embodiment.

Claims

1. A high-precision, high-flow electro-hydraulic proportional valve, characterized in that: include: A valve body (100), a valve core (200), a proportional solenoid (300), a displacement sensor, an external controller and a drive circuit; The valve core (200) is arranged at the end of the valve body (100), and the proportional electromagnet (300) is fixedly arranged on the outer surface of the valve body (100), and the displacement sensor is arranged inside the valve body (100); a limit hexagon (101) is fixedly arranged on the surface of the valve body (100) for facilitating the limiting and rotation of the valve body (100) when the valve body (100) is threadedly inserted, and a hexagonal nut (102) is threadedly connected to the surface of the valve body (100) for facilitating the installation of the proportional electromagnet (300); The proportional electromagnet (300) adopts N52 neodymium iron boron magnetic material to improve electromagnetic force output and increase flow rate; the controller adopts a digital signal processor DSP or a microcontroller MCU to achieve high-precision and high-speed digital control; the drive circuit adopts a PWM drive mode to improve the response speed and control accuracy of the electromagnet.

2. A high-precision, high-flow electro-hydraulic proportional valve according to claim 1, characterized in that: A circuit connector (400) for connecting to an external circuit is provided on the surface of the proportional electromagnet (300).

3. A high-precision, high-flow electro-hydraulic proportional valve according to claim 2, characterized in that: A positioning component (500) for positioning a cable connected to a line connector (400) is provided on the surface of the proportional electromagnet (300).

4. A high-precision, high-flow electro-hydraulic proportional valve according to claim 3, characterized in that: The positioning assembly (500) comprises two L-shaped mounting rods (501) fixedly mounted on the outer surface of the proportional electromagnet (300), and a positioning frame (502) fixedly mounted on the ends of the L-shaped mounting rods (501), wherein two symmetrical positioning clamping plates (503) are slidably mounted on the inner wall of the positioning frame (502).

5. A high-precision, high-flow electro-hydraulic proportional valve according to claim 4, characterized in that: Two semicircular positioning grooves corresponding to the cables are provided on opposite surfaces of the two positioning clamps (503), and semicircular rubber anti-skid pads (504) are fixedly provided on the inner walls of the four semicircular positioning grooves.

6. A high-precision, high-flow electro-hydraulic proportional valve according to claim 4, characterized in that: The positioning assembly (500) further comprises a connection box (505) fixedly mounted on the surface of the positioning frame (502), and a plum blossom turntable (506) rotatably mounted on the surface of the connection box (505) for driving the two positioning clamping plates (503) to move toward the middle simultaneously.

7. A high-precision, high-flow electro-hydraulic proportional valve according to claim 6, characterized in that: The inner wall of the positioning frame (502) is rotatably provided with two symmetrical bidirectional threaded columns (507), and the surfaces of the two positioning clamping plates (503) are provided with two threaded holes respectively threadedly connected to the outer surfaces of the two bidirectional threaded columns (507).

8. A high-precision, high-flow electro-hydraulic proportional valve according to claim 7, characterized in that: One end of each of the two bidirectional threaded columns (507) extends to the interior of the connection box (505); a rotating shaft (508) extending to the outer surface of the connection box (505) is rotatably provided on the inner wall of the connection box (505); and the plum blossom rotating disk (506) is fixedly arranged at the end of the rotating shaft (508).

9. A high-precision, high-flow electro-hydraulic proportional valve according to claim 8, characterized in that: A first transmission wheel (509) is fixedly arranged on the surface of the rotating shaft (508); second transmission wheels (5010) are fixedly arranged on the end surfaces of the two bidirectional threaded columns (507); two transmission belts (5011) are sleeved on the surface of the first transmission wheel (509); the other ends of the two transmission belts (5011) are respectively sleeved on the surfaces of the two second transmission wheels (5010); and the first transmission wheel (509) is synchronously transmission-connected to the two second transmission wheels (5010) via the two transmission belts (5011).

10. A control method for a high-precision, large-flow electro-hydraulic proportional valve, according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1, signal acquisition: the controller acquires the valve core (200) displacement signal and the system pressure signal fed back by the displacement sensor; S2, signal processing: The controller filters and amplifies the collected signals to eliminate noise interference, uses a low-pass filter to filter out signals higher than 120 Hz, and uses a signal amplifier to amplify the signal by 30 times; S3, control algorithm: The controller calculates the control quantity according to the preset control algorithm PID control; S4, drive output: the controller converts the control quantity into a PWM signal, drives the proportional solenoid (300) to operate, and controls the displacement of the valve core (200); S5, closed-loop control: The controller adjusts the control amount in real time according to the displacement signal of the valve core (200) fed back by the displacement sensor to achieve closed-loop control.

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