A vibration control system for a precision surface grinder

Abstract

The application discloses a kind of precision plane grinding machine's vibration control system, including upper disc loading air cylinder control system, bottom vibration isolator control system, motor drive control system and vibration sensor, upper disc loading air cylinder control system includes loading end vibration isolator, first, second air proportional pressure valve, industrial computer is connected with first, second air proportional pressure valve respectively, the pressure sensor on loading air cylinder is connected with industrial computer, loading end vibration isolator is set on loading air cylinder piston rod.The third air proportional pressure valve of bottom vibration isolator control system is connected with variable stiffness damping vibration isolator and industrial computer, and variable stiffness damping vibration isolator is set between grinding machine mainframe and installation base.Vibration sensor is provided on mainframe, and vibration sensor, motor drive control system are connected with industrial computer.Loading end vibration isolator and bottom vibration isolator are controlled by fuzzy self-adaptive PID, and the stiffness value and damping value of vibration isolator can be actively controlled, to improve or eliminate grinding machine overall working vibration.

Description

Technical Field

[0001] This invention relates to the field of vibration reduction technology for precision grinding machines, and particularly to a vibration reduction control system for a precision surface grinding machine. Background Technology

[0002] Precision machining is an advanced manufacturing technology characterized by micron-level or even nanometer-level precision. It is widely used in high-tech fields such as aerospace, medical devices, semiconductors, automobiles, and humanoid robots, including semiconductor processing, precision gears, precision worm gears, and precision bearings. It not only concerns the precise control of part dimensions but also involves a comprehensive improvement in surface quality, shape accuracy, and material properties. Precision grinding is a machining technology that uses micro-abrasives to perform micro-cutting on the surface of a workpiece, achieving sub-micron-level or even nanometer-level dimensional accuracy and extremely low surface roughness. It is widely used in high-tech fields such as precision instruments, semiconductors, optical components, and medical devices. A precision grinding machine consists of a grinding system (including a pressure device, available in conventional and ultrasonic grinding), a motor system and a mechanical transmission system (including a control system), a machine tool body system, and a base vibration isolator.

[0003] However, most grinding systems are loaded using a cylinder system, and the grinding machine has very high requirements for vibration control during operation. Different processes involve different abrasives, pressures, and temperatures. Under certain conditions, when the grinding pressure and the relative speed of the grinding tools reach a specific value, vibration is easily generated, creating a vibration source called a "working vibration source." Insufficient precision in the grinding machine's components can also generate vibration sources, called "precision vibration sources." Some structures can also generate "structural vibration sources." For "precision vibration sources," using qualified components or improving the precision of the components can eliminate the vibration source; "structural vibration sources" are structural design issues.

[0004] A simplified dynamic model of a grinding machine includes longitudinal vibration, lateral vibration, torsional vibration, and coupled vibration. Longitudinal vibration occurs between the upper loading cylinder system, the upper grinding tool and workpiece, the lower grinding tool, the lower grinding tool, the frame, and the transmission system; the frame and foundation; and the foundation and ground. Lateral and longitudinal vibrations exist between all transmission systems (shafts, gears, bearings, splines, couplings, etc.) and the frame. Generally, the focus is on controlling the upper and lower longitudinal vibrations of the grinding machine. However, in different installation and usage environments—where the stiffness and damping values ​​of the installation foundation vary (some are directly on the ground, others on floors)—the performance of the same grinding machine becomes unstable and uncertain, easily leading to vertical resonance (longitudinal vibration). Therefore, a vibration reduction control system with adjustable stiffness and damping is essential.

[0005] Existing grinding machines are not ideal in terms of vibration reduction to adapt to different working conditions and environments. Their performance is not stable enough under different grinding processes, meaning the system has poor robustness and is prone to generating large vibrations, thus affecting the precision grinding of workpieces. The stiffness and damping of existing grinding machine vibration isolators cannot be adaptively adjusted. When the working conditions of the grinding machine change, it cannot adapt well and cannot meet the requirements for long-term use. Summary of the Invention

[0006] To address the aforementioned problems, this invention aims to provide a vibration reduction control system for a precision surface grinding machine, thereby solving the problem that the stiffness and damping of the vibration reduction system of the precision grinding machine cannot be adaptively adjusted.

[0007] The technical problem solved by this invention can be achieved by the following technical solution: a vibration reduction control system for a precision surface grinding machine, comprising an upper plate loading cylinder control system, a bottom vibration isolator control system, a motor drive control system, and a vibration sensor. The upper plate loading cylinder control system includes a loading end vibration isolator, a regulated air source, a first air proportional pressure valve, and a second air proportional pressure valve. The regulated air source is connected to the loading cylinder through the first air proportional pressure valve and the second air proportional pressure valve, respectively. An industrial control computer is connected to the first air proportional pressure valve and the second air proportional pressure valve, respectively. A pressure sensor is connected to the piston rod output end of the loading cylinder, and the pressure sensor is connected to the industrial control computer. The loading cylinder is connected to a lifting cylinder and a linear displacement sensor, respectively. The linear displacement sensor is connected to the industrial control computer through an analog-to-digital converter. The loading end vibration isolator is mounted on the piston rod of the loading cylinder.

[0008] The bottom vibration isolator control system includes a variable stiffness damping isolator, a third air proportional pressure valve, and a regulated air source. The third air proportional pressure valve is connected to the variable stiffness damping isolator, which is positioned between the main frame of the grinding machine and the mounting foundation. The regulated air source is connected to the third air proportional pressure valve, which is also connected to an industrial control computer. Vibration sensors are installed on the main frame and are connected to the industrial control computer. The motor drive control system is connected to the industrial control computer via an analog-to-digital converter.

[0009] The vibration isolator at the loading end is a variable stiffness magnetorheological damper, which is connected to an industrial control computer via a digital-to-analog converter and a power amplifier.

[0010] The first and second air proportional pressure valves are connected to a PID controller via a digital-to-analog converter. The PID controller is connected to a fuzzy controller by adjusting the values ​​of ΔKp, ΔKi, and ΔKd. The PID controller is also connected to a current controller, which is connected to the electromagnetic coil of the variable stiffness magnetorheological damper. The loading cylinder is connected to the variable stiffness magnetorheological damper. The electromagnetic coil and the magnetorheological fluid are located within the variable stiffness magnetorheological damper. The electromagnetic coil controls the stiffness and damping of the magnetorheological fluid, and controls the damping and stiffness of the variable stiffness magnetorheological damper by controlling the current in the electromagnetic coil. A pressure sensor is connected to the piston rod of the loading cylinder to measure the dynamic grinding pressure, which serves as the input auxiliary value for the fuzzy PID control. A vibration sensor is connected to the frame to measure the vibration value, which serves as the input value for the fuzzy PID control. The pressure sensor and the vibration sensor on the main frame are connected to the fuzzy controller via negative feedback adjustment.

[0011] The vibration isolator at the loading end is a spring vibration isolator.

[0012] The first and second air proportional pressure valves are respectively connected to a PID controller via a digital-to-analog converter. The PID controller is connected to a fuzzy controller by adjusting the values ​​of ΔKp, ΔKi, and ΔKd. The pressure sensor is connected to the piston rod of the cylinder to measure the dynamic grinding pressure, which is used as the input auxiliary value for the fuzzy PID control. The dynamic grinding pressure generated by the loading cylinder causes the main frame to vibrate. The vibration sensor is connected to the main frame and measures the vibration value, which is used as the input value for the fuzzy PID control. The pressure sensor and the vibration sensor on the main frame are respectively connected to the fuzzy controller through negative feedback adjustment.

[0013] The pressure sensor is connected to the piston rod of the cylinder to measure the dynamic grinding pressure, which is used as the input auxiliary value for fuzzy PID control. The dynamic grinding pressure generated by the loading cylinder causes the main frame to vibrate. The vibration sensor is connected to the main frame to measure the vibration value, which is used as the input value for fuzzy PID control. The variable stiffness damping vibration isolator is a variable stiffness damping airbag vibration isolator, which includes an isolator cylinder, an isolator base plate, an isolator top cover, an airbag cylinder, a variable pressure inflation airbag, a valve, a spring rod, a disc spring, and a rubber block. The isolator cylinder is fixedly connected to the isolator base plate, and the isolator top cover is slidably connected to the isolator cylinder. A sealing ring is provided between the isolator top cover and the isolator cylinder. The isolator cylinder, the isolator base plate, the isolator top cover, and the valve together form a sealed cavity. The airbag cylinder and the variable pressure inflation airbag are arranged inside the sealed cavity. An airbag, a variable pressure inflatable airbag, surrounds the airbag cylinder. The variable pressure inflatable airbag is equipped with a valve, which is connected to a third air proportional pressure valve. The variable pressure inflatable airbag is equipped with a ring of damping small air holes. The vibration isolator cylinder is equipped with a waist ring. The airbag cylinder is equipped with a spring rod and multiple disc springs. The disc springs are sleeved on the spring rod. The lower end of the spring rod is fixedly connected to the center of the vibration isolator base plate. The upper end of the disc spring is in contact with the vibration isolator top cover. The lower end of the disc spring is in contact with the vibration isolator base plate. Rubber blocks are set between the disc springs.

[0014] The airbag is connected to the main frame via a vibration isolator cover. A vibration sensor is installed on the main frame. The vibration sensor is connected to a fuzzy controller via negative feedback adjustment. The third air proportional controller is connected to a PID controller. The PID controller is connected to the fuzzy controller by adjusting the values ​​of ΔKp, ΔKi, and ΔKd.

[0015] The variable stiffness damping vibration isolator is a variable stiffness damping air-filled magnetohydrodynamic vibration isolator. The variable stiffness damping air-filled magnetohydrodynamic vibration isolator includes an isolator cylinder, an isolator base plate, an isolator top cover, magnetohydrodynamic rubber, an upper sealing ring, a lower sealing ring, a valve, a helical electromagnetic coil, a coil seat, and a pad. The isolator cylinder is fixedly connected to the isolator base plate, and the isolator top cover is slidably connected to the isolator cylinder. An upper sealing ring is provided between the isolator top cover and the isolator cylinder. A lower sealing ring is provided between the isolator cylinder and the isolator base plate. The isolator cylinder, the isolator base plate, the isolator top cover, and the valve together form a sealed air cylinder. Magnetic fluid rubber is installed inside the air cylinder. The upper end of the magnetic fluid rubber is connected to the isolator top cover, and the lower end is connected to the isolator base plate. A helical electromagnetic coil is sleeved on the magnetic fluid rubber. A coil seat and a pad are provided between the upper end of the helical electromagnetic coil and the isolator top cover. The valve is connected to a third air proportional pressure valve.

[0016] The third air proportional pressure valve is connected to a PID controller. The PID controller is connected to a fuzzy controller by adjusting the values ​​of ΔKp, ΔKi, and ΔKd. The PID controller is connected to a current controller, which is connected to an electromagnetic coil. The air cylinder and the electromagnetic coil are connected in parallel to the main frame. A vibration sensor is installed on the main frame. The vibration sensor is connected to the fuzzy controller through negative feedback adjustment.

[0017] A control method for a vibration reduction control system based on a precision surface grinder, wherein the vibration sensor measures the vibration value of the main frame, and the value is connected to an industrial control computer via an analog-to-digital converter to compare whether it is greater than a predetermined value; Ⅰ If the vibration value measured by the vibration sensor after the cycle is greater than the predetermined value, the industrial control computer changes the damping and stiffness values ​​through a digital-to-analog converter, a power amplifier, and a variable stiffness magnetorheological damper connected to the loading cylinder. Then, it detects the vibration value of the main frame and compares it with the predetermined value. If it is less than the predetermined value, the problem is solved and the cycle ends. If it is greater than the predetermined value and the problem is still not solved, the damping and stiffness values ​​are changed again, and the vibration value of the main frame is detected and compared with the predetermined value until it is less than the predetermined value. At the same time, the pressure sensor obtains the loading end pressure value (auxiliary input, enters the fuzzy PID control cycle, and performs auxiliary control). The loading end pressure value cannot exceed the predetermined grinding pressure value. II. If the vibration value measured by the vibration sensor after the cycle is greater than the predetermined value, the industrial control computer connects to the first and second air proportional pressure valves via a digital-to-analog converter and power amplifier to increase the pressure of the loading cylinder. Then, it detects the vibration value of the main frame and compares it with the predetermined value. If it is less than the predetermined value, the problem is solved and the cycle ends. If it is greater than the predetermined value and the problem is still not solved, the pressure of the loading cylinder is increased again, and the vibration value of the main frame is detected and compared with the predetermined value until it is less than the predetermined value. At the same time, the pressure sensor obtains the loading end pressure value (auxiliary input, entering the fuzzy PID control cycle for auxiliary control). The loading end pressure value must not exceed the predetermined grinding pressure value. Steps I and II can be performed simultaneously. Ⅲ If the vibration value measured by the vibration sensor after the cycle is greater than the predetermined value, and the problem is still not solved, the industrial control computer connects to the motor drive control system through an analog-to-digital converter, changes the damping and stiffness of the motor drive control system, and then detects the vibration value of the main frame to compare with whether it is greater than the predetermined value. If it is less than the predetermined value, the problem is solved and the cycle ends. If it is greater than the predetermined value and the problem is still not solved, the damping and stiffness of the motor drive are changed again, and the vibration value of the main frame is detected to compare with whether it is greater than the predetermined value, until it is less than the predetermined value. IV. If the vibration value measured by the vibration sensor after the cycle is greater than the predetermined value, and the problem is still not solved, the industrial control computer connects to the third air proportional pressure valve and the variable stiffness damping vibration isolator through the digital-to-analog converter and power amplifier. The damping and stiffness of the vibration isolator are changed, and then the vibration value of the main frame is detected and compared to whether it is greater than the predetermined value. If it is less than the predetermined value, the problem is solved, and the cycle ends. If it is greater than the predetermined value, and the problem is still not solved, the damping and stiffness of the vibration isolator are changed again, and the vibration value of the main frame is detected and compared to whether it is greater than the predetermined value, until it is less than the predetermined value. Steps III and IV can be performed simultaneously. V. If the vibration value measured by the vibration sensor after the cycle is greater than the predetermined value, and the problem is still not solved, change the design parameters of the main frame, change the stiffness and damping of the main frame, and then detect the vibration value of the machine tool body to compare whether it is greater than the predetermined value; if it is greater than the predetermined value, continue to change the design parameters of the main frame, change the stiffness and damping of the main frame; if it is less than the predetermined value, the problem is solved and the cycle ends. VI. If the vibration value measured by the vibration sensor after the cycle is greater than the predetermined value and the problem is still not solved, improve the accuracy of the key components, and then detect the vibration value of the main frame to compare whether it is greater than the predetermined value. If it is greater than the predetermined value, continue to improve the accuracy of the key components. If it is less than the predetermined value, the problem is solved and the cycle ends. V and VI can be performed simultaneously.

[0018] Compared with the prior art, the present invention has the following advantages: The present invention sets a loading end vibration isolator on the loading cylinder of the precision grinding machine and installs a bottom vibration isolator between the bottom of the grinding machine and the main frame; the loading end vibration isolator and the bottom vibration isolator are controlled by fuzzy adaptive PID control, and the stiffness and damping values ​​of the vibration isolator can be actively controlled, thereby improving or eliminating the overall working vibration of the grinding machine, and the precision grinding machine has strong robustness. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the first embodiment of the loading cylinder of the present invention; Figure 2 Here is a block diagram of the fuzzy adaptive PID control for the upper plate loading cylinder control system in Example 1; Figure 3 This is a schematic diagram of the structure of Embodiment 2 of the loading cylinder end of the present invention; Figure 4 This is a fuzzy adaptive PID control block diagram of the upper plate loading cylinder control system in Example 2; Figure 5 This is a schematic diagram of a variable stiffness damping airbag vibration isolator. Figure 6 The block diagram of fuzzy adaptive PID control for a variable stiffness damped airbag vibration isolator; Figure 7This is a schematic diagram of a variable stiffness damped air cylinder magnetohydrodynamic vibration isolator. Figure 8 The block diagram of fuzzy adaptive PID control for a variable stiffness damped air cylinder magnetohydrodynamic vibration isolator; Figure 9 This is the control flowchart of the present invention; In the diagram: 1-Spring rod, 2-Isolator top cover, 3-Airbag cylinder, 4-Valve, 5-Annular inflatable airbag, 6-Disc spring, 7-Isolator base plate, 8-Hex socket screw, 9-Rubber pad, 10-Isolator cylinder, 11-Rubber block, 12-Damping small air hole, 13-Waist ring, 14-Pad plate, 15-Coil seat, 16-Helical electromagnetic coil, 17-Magnetic fluid rubber, 18-Lower sealing ring, 19-Upper sealing ring. Detailed Implementation

[0020] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below with reference to specific illustrations.

[0021] In the description of this invention, it should be understood that the terms "one end", "the other end", "outer side", "upper", "inner side", "horizontal", "coaxial", "center", "end", "length", "outer end", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0022] Combined with appendix Figures 1 to 9 As shown, this embodiment discloses a vibration reduction control system for a precision surface grinding machine, including an upper loading cylinder control system, a bottom vibration isolator control system, a motor drive control system, and a vibration sensor. The upper loading cylinder control system includes a loading end vibration isolator, a regulated air source, a first air proportional pressure valve, and a second air proportional pressure valve. The regulated air source is connected to the loading cylinder via the first and second air proportional pressure valves. The industrial control computer is connected to the first and second air proportional pressure valves via a digital-to-analog converter and a power amplifier. A pressure sensor is connected to the output end of the piston rod of the loading cylinder, and the pressure sensor is connected to the industrial control computer via an analog-to-digital converter. The loading cylinder is connected to a lifting cylinder and a linear displacement sensor, and the linear displacement sensor is connected to the industrial control computer via an analog-to-digital converter. The loading end vibration isolator is mounted on the piston rod of the loading cylinder.

[0023] The bottom vibration isolator control system includes a variable stiffness damping isolator and a third air proportional pressure valve. The third air proportional pressure valve is connected to the variable stiffness damping isolator, which is positioned between the main frame of the grinding machine and the mounting foundation (there are two types of mounting foundations: one where the main frame is directly mounted on the ground floor, and another where the main frame is mounted on a floor above the second floor). The regulated air source is connected to the third air proportional pressure valve, which is connected to the industrial control computer via a digital-to-analog converter and a power amplifier. Vibration sensors are installed on the main frame, and these sensors are connected to the industrial control computer via an analog-to-digital converter. The motor drive control system communicates with the industrial control computer via the analog-to-digital converter and uses fuzzy adaptive PID control.

[0024] The loading cylinder's pressure is controlled by a first and second proportional air pressure valve, using a fuzzy adaptive PID control method, with the industrial computer acting as the controller. The variable stiffness damping isolator's pressure is controlled by a third proportional air pressure valve, communicating with the industrial computer via a power amplifier and digital-to-analog converter, also using a fuzzy adaptive PID control method. The variable stiffness damping isolator integrates active and passive vibration isolation. A regulated air source provides continuous gas power. A linear position sensor measures the displacement of the loading cylinder driven by the lifting cylinder. A vibration sensor measures the vibration value of the main frame. A pressure sensor measures the pressure of the loading cylinder.

[0025] like Figure 1 As shown, the vibration isolator at the loading end is a variable stiffness magnetorheological damper, which is connected to an industrial control computer via a digital-to-analog converter and a power amplifier. The upper plate loading cylinder control system is a longitudinal vibration active damping control system.

[0026] like Figure 2As shown, the first and second air proportional pressure valves are connected to a PID controller via a digital-to-analog converter. The PID controller is connected to a fuzzy controller by adjusting the values ​​of ΔKp, ΔKi, and ΔKd. The PID controller is also connected to a current controller, which is connected to the electromagnetic coil on the variable stiffness magnetorheological damper. The loading cylinder is connected to the variable stiffness magnetorheological damper. The electromagnetic coil and the magnetorheological fluid are located within the variable stiffness magnetorheological damper. The electromagnetic coil controls the stiffness and damping of the magnetorheological fluid and controls the damping and stiffness of the variable stiffness magnetorheological damper by controlling the current in the electromagnetic coil. A pressure sensor is connected to the piston rod of the loading cylinder to measure the working dynamic grinding pressure as an auxiliary input value for the fuzzy PID control. A vibration sensor is connected to the frame to measure the vibration value as an input value for the fuzzy PID control. The pressure sensor (as an auxiliary input) and the vibration sensor on the main frame (as the main input) are connected to the fuzzy controller via negative feedback adjustment. The variable stiffness magnetorheological damper contains an electromagnetic coil. The electromagnetic coil generates electromagnetic flux to control the viscosity and stiffness of the magnetorheological fluid, thereby changing the stiffness and damping. Changing the current in the electromagnetic coil changes the magnetic flux and the damping value.

[0027] Fuzzy adaptive PID control, based on the PID algorithm, uses the error *e* and the rate of change of error *ec* as inputs. It employs fuzzy rules for fuzzy inference and consults a fuzzy matrix table to adjust parameters, satisfying the self-tuning requirements of *e* and *ec* at different times for the PID parameters. While PID control is simple in principle, easy to use, and highly adaptable, it also has drawbacks such as low timing accuracy and poor anti-interference capability. Fuzzy adaptive PID control, by using fuzzy logic and eliminating the need for precise mathematical models, offers advantages such as ease of use and high adaptability. The addition of a fuzzy adaptive controller significantly increases overall robustness.

[0028] like Figure 3 As shown, the loading end vibration isolator is a spring vibration isolator. The spring vibration isolator is a passive vibration isolator (working vibration damper) composed of a cylindrical spring, a piston, and a sealing ring. The upper plate loading cylinder control system is a longitudinal vibration active and passive vibration damping control system.

[0029] like Figure 4As shown, the first and second air proportional pressure valves are connected to a PID controller via a digital-to-analog converter. The PID controller is connected to a fuzzy controller by adjusting the values ​​of ΔKp, ΔKi, and ΔKd. The pressure sensor is connected to the piston rod of the cylinder to measure the dynamic grinding pressure, which is used as the input auxiliary value for the fuzzy PID control. The dynamic grinding pressure generated by the loading cylinder causes the main frame to vibrate. The vibration sensor is connected to the main frame and measures the vibration value, which is used as the input value for the fuzzy PID control. The pressure sensor and the vibration sensor on the main frame are connected to the fuzzy controller via negative feedback adjustment.

[0030] The loading-end vibration isolator of this invention is a variable stiffness magnetorheological damper or a spring vibration isolator; the variable stiffness damping vibration isolator is a variable stiffness damping airbag vibration isolator or a variable stiffness damping air cylinder magnetorheological vibration isolator. These four solutions can be used in combination as needed. The variable stiffness damping vibration isolator at the bottom can improve or eliminate overall operating vibration. The loading-end vibration isolator can change the stiffness and damping at the loading end, thereby improving or eliminating overall operating vibration.

[0031] like Figure 5 As shown, the variable stiffness damping vibration isolator is a variable stiffness damping airbag vibration isolator. The variable stiffness damping airbag vibration isolator includes a vibration isolator cylinder 10, a vibration isolator base plate 7, a vibration isolator top cover 2, an airbag cylinder 3, a variable pressure inflation airbag 5, a valve 4, a spring rod 1, a disc spring 6, and a rubber block 11. The vibration isolator cylinder 10 is fixedly connected to the vibration isolator base plate 7, and the vibration isolator top cover 2 is slidably connected to the vibration isolator cylinder 10. A sealing ring is provided between the vibration isolator top cover 2 and the vibration isolator cylinder 10. The vibration isolator cylinder 10, the vibration isolator base plate 7, the vibration isolator top cover 2, and the valve 4 together form a sealed cavity. The sealed cavity contains an airbag cylinder 3 and a variable-pressure inflatable airbag 5, which surrounds the airbag cylinder 3. The variable-pressure inflatable airbag 5 is equipped with a valve 4, which is connected to a third air proportional pressure valve. The valve 4 is used to connect an air source to inflate and deflate the variable-pressure inflatable airbag 5, thereby adjusting the stiffness and damping of the vibration isolator to adapt to different operating conditions of the grinding machine. A vibration isolator with appropriate stiffness has a good vibration reduction effect. The variable-pressure inflatable airbag 5 has a ring of small damping air holes 12, and a corresponding waist ring 13 is provided on the cylinder 10 of the vibration isolator. The waist ring 13 is used to store the volume of the variable-pressure inflatable airbag 5 when compressed.

[0032] The airbag cylinder 3 is equipped with a spring rod 1 and multiple disc springs 6. The disc springs 6 are sleeved on the spring rod 1. The lower end of the spring rod 1 is fixedly connected to the center of the vibration isolator base plate 7. The upper end of the disc spring 6 is in contact with the vibration isolator top cover 2, and the lower end of the disc spring 6 is in contact with the vibration isolator base plate 7. Rubber blocks 11 are placed between the disc springs 6. The disc springs 6 have strong load-bearing capacity and small deformation, which can generate strong variable damping and have good buffering and shock absorption capabilities. The disc spring combination provides passive vibration isolation stiffness and damping, isolating high-frequency vibrations. Passive vibration isolation has resonance peaks. In order to reduce the resonance peaks, the damping of the vibration isolator can be increased. Therefore, rubber blocks 11 are added between the disc springs 6 to increase damping. However, this will cause the high-frequency band of the transmissivity curve to rise, thus sacrificing high-frequency vibration isolation performance. Applying active control on top of passive vibration isolation reduces the resonance peak of passive isolation, improving the low-frequency vibration isolation performance of the system, while still using passive isolation in the high-frequency band. This achieves full-band vibration isolation and reduces system energy consumption. Active control of the pneumatic vibration isolation system is based on the basic idea of ​​adaptively adjusting the actuator output force according to the system's disturbance input signal, so that the load's response to the actuator force cancels out the disturbance input response, achieving the purpose of eliminating load vibration. Active control of the airbag in the pneumatic vibration isolation system, through pressure feedback from the isolator's sealed cavity, achieves the purpose of eliminating load vibration through a fuzzy adaptive PID controller.

[0033] The variable pressure inflatable airbag 5 is made of rubber. When the precision grinding machine vibrates, the vibration isolator cover 2 also vibrates up and down, squeezing the disc spring 6 and the variable pressure inflatable airbag 5. During the vibration, the volume of the variable pressure inflatable airbag 5 will alternately increase and decrease, and it will alternately deflate and inhale through the damping small air hole 12, thereby generating damping. The disc spring 6 can generate strong variable damping. When the disc spring assembly is repeatedly compressed and deformed, friction and deformation between the disc springs 6 generate a large amount of heat, which consumes vibration energy.

[0034] A rubber pad 9 is provided at the bottom of the vibration isolator base plate 7, and the rubber pad 9 is fixedly connected to the vibration isolator base plate 7 by an internal hex screw 8.

[0035] like Figure 6 As shown, the airbag is connected to the main frame via a vibration isolator cover. A vibration sensor is installed on the main frame. The vibration sensor is connected to the fuzzy controller via negative feedback adjustment. The third air proportional controller is connected to the PID controller. The PID controller is connected to the fuzzy controller by adjusting the values ​​of ΔKp, ΔKi, and ΔKd.

[0036] A PID controller actively controls the pneumatic vibration isolation system. This method adaptively adjusts the actuator output force based on the system's disturbance input signal, so that the load's response to the actuator force cancels out the disturbance input response, thus eliminating load vibration. The airbag is the pneumatic vibration isolation system. Active control of the airbag, using air chamber pressure and position feedback, is achieved through a fuzzy adaptive PID controller to eliminate load vibration. The variable-stiffness damping airbag acts as the actuator. Due to the actuator's bandwidth limitations, active control is only effective in the low-frequency range. At high frequencies, active control becomes ineffective, and the system exhibits passive vibration isolation characteristics. Therefore, variable stiffness damping airbag vibration isolators can achieve full-frequency vibration isolation.

[0037] like Figure 7 As shown, the variable stiffness damping vibration isolator is a variable stiffness damping air-filled magnetic fluid vibration isolator. The variable stiffness damping air-filled magnetic fluid vibration isolator includes an isolator cylinder 10, an isolator base plate 7, an isolator top cover 2, magnetic fluid rubber 17, an upper sealing ring 19, a lower sealing ring 18, a valve 4, a spiral electromagnetic coil 16, a coil seat 15, and a pad 14. The isolator cylinder 10 is fixedly connected to the isolator base plate 7, and the isolator top cover 2 is slidably connected to the isolator cylinder 10. The isolator top cover 2 is connected to the isolator cylinder 10. An upper sealing ring 19 is provided between the cylinders 10 of the isolator and the base plate 7 of the isolator. A lower sealing ring 18 is provided between the cylinder 10 and the base plate 7 of the isolator. The cylinder 10, the base plate 7, the top cover 2, and the valve 4 together form a sealed air cylinder. A magnetic fluid rubber 17 is provided inside the air cylinder. The upper end of the magnetic fluid rubber 17 is connected to the top cover 2 of the isolator, and the lower end is connected to the base plate 7. A spiral electromagnetic coil 16 is fitted on the magnetic fluid rubber 17. The valve is connected to a third air proportional pressure valve. A coil seat 15 and a pad 14 are provided between the upper end of the magnetic fluid rubber 17 and the upper end of the spiral electromagnetic coil 16 and the top cover 2 of the isolator. A rubber pad 9 is provided at the bottom of the base plate 7 of the isolator. The rubber pad 9 is fixedly connected to the base plate 7 of the isolator by an internal hexagon screw 8.

[0038] like Figure 8 As shown, the third air proportional pressure valve is connected to a PID controller. The PID controller is connected to a fuzzy controller by adjusting the values ​​of ΔKp, ΔKi, and ΔKd. The PID controller is also connected to a current controller, which is connected to an electromagnetic coil. The air cylinder and the electromagnetic coil are connected in parallel to the main frame. A vibration sensor is installed on the main frame, and the vibration sensor is connected to the fuzzy controller through negative feedback adjustment. The air cylinder and magnetohydrodynamic rubber serve as actuators.

[0039] like Figure 9 As shown, a control method for a vibration reduction control system based on a precision surface grinding machine is described. The vibration sensor measures the vibration value of the main frame, which is then connected to an industrial control computer via an analog-to-digital converter to compare whether it exceeds a predetermined value. Ⅰ If the vibration value measured by the vibration sensor after the cycle is greater than the predetermined value, the industrial control computer changes the damping and stiffness values ​​through a digital-to-analog converter, a power amplifier, and a variable stiffness magnetorheological damper (active damper) connected to the loading cylinder. Then, it detects the vibration value of the main frame and compares it with the predetermined value. If it is less than the predetermined value, the problem is solved and the cycle ends. If it is greater than the predetermined value and the problem is still not solved, the damping and stiffness values ​​are changed again, and the vibration value of the main frame is detected and compared with the predetermined value until it is less than the predetermined value. At the same time, the pressure sensor obtains the loading end pressure value (auxiliary input, enters the fuzzy PID control cycle, and performs auxiliary control). The loading end pressure value cannot exceed the predetermined grinding pressure value. II. If the vibration value measured by the vibration sensor after the cycle is greater than the predetermined value, the industrial control computer connects to the first and second air proportional pressure valves via a digital-to-analog converter and power amplifier to increase the pressure of the loading cylinder. Then, it detects the vibration value of the main frame and compares it with the predetermined value. If it is less than the predetermined value, the problem is solved and the cycle ends. If it is greater than the predetermined value and the problem is still not solved, the pressure of the loading cylinder is increased again, and the vibration value of the main frame is detected and compared with the predetermined value until it is less than the predetermined value. At the same time, the pressure sensor obtains the loading end pressure value (auxiliary input, entering the fuzzy PID control cycle for auxiliary control). The loading end pressure value must not exceed the predetermined grinding pressure value. Steps I and II can be performed simultaneously. Ⅲ If the vibration value measured by the vibration sensor after the cycle is greater than the predetermined value, and the problem is still not solved, the industrial control computer connects to the motor drive control system through an analog-to-digital converter, changes the damping and stiffness of the motor drive control system, and then detects the vibration value of the main frame to compare with whether it is greater than the predetermined value. If it is less than the predetermined value, the problem is solved and the cycle ends. If it is greater than the predetermined value and the problem is still not solved, the damping and stiffness of the motor drive are changed again, and the vibration value of the main frame is detected to compare with whether it is greater than the predetermined value, until it is less than the predetermined value. IV. If the vibration value measured by the vibration sensor after the cycle is greater than the predetermined value, and the problem is still not solved, the industrial control computer connects to the third air proportional pressure valve and the variable stiffness damping vibration isolator through the digital-to-analog converter and power amplifier. The damping and stiffness of the vibration isolator are changed, and then the vibration value of the main frame is detected and compared to whether it is greater than the predetermined value. If it is less than the predetermined value, the problem is solved, and the cycle ends. If it is greater than the predetermined value, and the problem is still not solved, the damping and stiffness of the vibration isolator are changed again, and the vibration value of the main frame is detected and compared to whether it is greater than the predetermined value, until it is less than the predetermined value. Steps III and IV can be performed simultaneously. V. If the vibration value measured by the vibration sensor after the cycle is greater than the predetermined value, and the problem is still not solved, change the design parameters of the main frame, change the stiffness and damping of the main frame, and then detect the vibration value of the machine tool body to compare whether it is greater than the predetermined value; if it is greater than the predetermined value, continue to change the design parameters of the main frame, change the stiffness and damping of the main frame; if it is less than the predetermined value, the problem is solved and the cycle ends. VI. If the vibration value measured by the vibration sensor after the cycle is greater than the predetermined value and the problem is still not solved, improve the accuracy of the key components, and then detect the vibration value of the main frame to compare whether it is greater than the predetermined value. If it is greater than the predetermined value, continue to improve the accuracy of the key components. If it is less than the predetermined value, the problem is solved and the cycle ends. V and VI can be performed simultaneously.

[0040] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any way. Any simple modifications, equivalent changes, or alterations made to the above embodiments based on the technical principles of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A vibration reduction control system for a precision surface grinding machine, comprising an upper plate loading cylinder control system, a bottom vibration isolator control system, a motor drive control system, and a vibration sensor, characterized in that: The upper loading cylinder control system includes a loading end vibration isolator, a regulated air source, a first proportional air pressure valve, a second proportional air pressure valve, and an industrial control computer. The regulated air source is connected to the loading cylinder through the first and second proportional air pressure valves. The industrial control computer is connected to both the first and second proportional air pressure valves. A pressure sensor is connected to the piston rod output end of the loading cylinder, and the pressure sensor is connected to the industrial control computer. The loading cylinder is connected to a lifting cylinder and a linear displacement sensor. The linear displacement sensor is connected to the industrial control computer. The machine is connected to the loading end vibration isolator, which is mounted on the piston rod of the loading cylinder. The bottom vibration isolator control system includes a variable stiffness damping vibration isolator and a third air proportional pressure valve. The third air proportional pressure valve is connected to the variable stiffness damping vibration isolator, which is located between the main frame of the grinding machine and the mounting foundation. The stabilizing air source is connected to the third air proportional pressure valve, which is connected to the industrial control computer. The motor drive control system is connected to the industrial control computer. A vibration sensor is installed on the main frame and is connected to the industrial control computer.

2. The vibration reduction control system for a precision surface grinding machine according to claim 1, characterized in that: The vibration isolator at the loading end is a variable stiffness magnetorheological damper, which is connected to an industrial control computer via a digital-to-analog converter and a power amplifier.

3. The vibration reduction control system for a precision surface grinding machine according to claim 2, characterized in that: The first and second air proportional pressure valves are connected to a PID controller via a digital-to-analog converter. The PID controller is connected to a fuzzy controller by adjusting the values ​​of ΔKp, ΔKi, and ΔKd. The PID controller is also connected to a current controller, which is connected to the electromagnetic coil of the variable stiffness magnetorheological damper. The loading cylinder is connected to the variable stiffness magnetorheological damper. The electromagnetic coil and the magnetorheological fluid are located within the variable stiffness magnetorheological damper. The electromagnetic coil controls the stiffness and damping of the magnetorheological fluid, and controls the damping and stiffness of the variable stiffness magnetorheological damper by controlling the current in the electromagnetic coil. A pressure sensor is connected to the piston rod of the loading cylinder to measure the dynamic grinding pressure, which serves as the input auxiliary value for the fuzzy PID control. A vibration sensor is connected to the frame to measure the vibration value, which serves as the input value for the fuzzy PID control. The pressure sensor and the vibration sensor on the main frame are connected to the fuzzy controller via negative feedback adjustment.

4. The vibration reduction control system for a precision surface grinding machine according to claim 1, characterized in that: The vibration isolator at the loading end is a spring vibration isolator.

5. The vibration reduction control system for a precision surface grinding machine according to claim 4, characterized in that: The first and second air proportional pressure valves are respectively connected to a PID controller via a digital-to-analog converter. The PID controller is connected to a fuzzy controller by adjusting the values ​​of ΔKp, ΔKi, and ΔKd. The pressure sensor is connected to the piston rod of the cylinder to measure the dynamic grinding pressure, which is used as the input auxiliary value for the fuzzy PID control. The dynamic grinding pressure generated by the loading cylinder causes the main frame to vibrate. The vibration sensor is connected to the main frame and measures the vibration value, which is used as the input value for the fuzzy PID control. The pressure sensor and the vibration sensor on the main frame are respectively connected to the fuzzy controller through negative feedback adjustment.

6. The vibration reduction control system for a precision surface grinding machine according to claim 1, characterized in that: The variable stiffness damping vibration isolator is a variable stiffness damping airbag vibration isolator. The variable stiffness damping airbag vibration isolator includes a vibration isolator cylinder (10), a vibration isolator base plate (7), a vibration isolator top cover (2), an airbag cylinder (3), a variable pressure inflation airbag (5), a valve (4), a spring rod (1), a disc spring (6), and a rubber block (11). The vibration isolator cylinder (10) is fixedly connected to the vibration isolator base plate (7), and the vibration isolator top cover (2) is slidably connected to the vibration isolator cylinder (10). A sealing ring is provided between the vibration isolator top cover (2) and the vibration isolator cylinder (10). The vibration isolator cylinder (10), the vibration isolator base plate (7), the vibration isolator top cover (2), and the valve (4) together constitute a sealed cavity. The sealed cavity contains an airbag cylinder (3) and a variable pressure inflation airbag (5). A variable pressure inflatable airbag (5) surrounds the airbag cylinder (3). The variable pressure inflatable airbag (5) is provided with a valve (4), which is connected to a third air proportional pressure valve. A ring of damping small air holes (12) is provided on the variable pressure inflatable airbag (5). A waist ring (13) is provided on the cylinder (10) of the vibration isolator. A spring rod (1) and multiple disc springs (6) are provided inside the airbag cylinder (3). The disc springs (6) are sleeved on the spring rod (1). The lower end of the spring rod (1) is fixedly connected to the center of the vibration isolator base plate (7). The upper end of the disc spring (6) is in contact with the vibration isolator cover (2). The lower end of the disc spring (6) is in contact with the vibration isolator base plate (7). Rubber blocks (11) are provided between the disc springs (6).

7. The vibration reduction control system for a precision surface grinding machine according to claim 6, characterized in that: The airbag is connected to the main frame via a vibration isolator cover. A vibration sensor is installed on the main frame. The vibration sensor is connected to a fuzzy controller via negative feedback adjustment. The third air proportional controller is connected to a PID controller. The PID controller is connected to the fuzzy controller by adjusting the values ​​of ΔKp, ΔKi, and ΔKd.

8. The vibration reduction control system for a precision surface grinding machine according to claim 1, characterized in that: The variable stiffness damping vibration isolator is a variable stiffness damping air cylinder magnetic fluid vibration isolator. The variable stiffness damping air cylinder magnetic fluid vibration isolator includes a vibration isolator cylinder (10), a vibration isolator base plate (7), a vibration isolator top cover (2), magnetic fluid rubber (17), an upper sealing ring (19), a lower sealing ring (18), a valve (4), a spiral electromagnetic coil (16), a coil seat (15), and a pad (14). The vibration isolator cylinder (10) is fixedly connected to the vibration isolator base plate (7), and the vibration isolator top cover (2) is slidably connected to the vibration isolator cylinder (10). An upper sealing ring (19) is provided between the vibration isolator top cover (2) and the vibration isolator cylinder (10). A lower sealing ring (18) is provided between the vibrator cylinder (10) and the vibration isolator base plate (7). The vibration isolator cylinder (10), the vibration isolator base plate (7), the vibration isolator top cover (2) and the valve (4) together form a sealed air cylinder. A magnetic fluid rubber (17) is provided inside the air cylinder. The upper end of the magnetic fluid rubber (17) is connected to the vibration isolator top cover (2) and the lower end is connected to the vibration isolator base plate (7). A spiral electromagnetic coil (16) is sleeved on the magnetic fluid rubber (17). A coil seat (15) and a pad (14) are provided between the upper end of the spiral electromagnetic coil (16) and the vibration isolator top cover (2). The valve (4) is connected to the third air proportional pressure valve.

9. The vibration reduction control system for a precision surface grinding machine according to claim 1, characterized in that: The third air proportional pressure valve is connected to a PID controller. The PID controller is connected to a fuzzy controller by adjusting the values ​​of ΔKp, ΔKi, and ΔKd. The PID controller is connected to a current controller, which is connected to an electromagnetic coil. The air cylinder and the electromagnetic coil are connected in parallel to the main frame. A vibration sensor is installed on the main frame. The vibration sensor is connected to the fuzzy controller through negative feedback adjustment.

10. A control method for a vibration reduction control system of a precision surface grinding machine according to any one of claims 1-9, characterized in that: The vibration sensor measures the vibration value of the main frame, and connects it to the industrial control computer through an analog-to-digital converter to compare whether it is greater than a predetermined value; Ⅰ If the vibration value measured by the vibration sensor after the cycle is greater than the predetermined value, the industrial control computer connects to the variable stiffness magnetorheological damper connected to the loading cylinder, changes the damping value and stiffness value, and then detects the vibration value of the main frame to compare whether it is greater than the predetermined value; if it is less than the predetermined value, the problem is solved and the cycle ends; if it is greater than the predetermined value and the problem is still not solved, the damping value and stiffness value are changed again, and the vibration value of the main frame is detected to compare whether it is greater than the predetermined value, until it is less than the predetermined value; the pressure sensor obtains the loading end pressure value, which is used as an auxiliary input to enter the fuzzy PID control cycle for auxiliary control. The loading end pressure value cannot exceed the predetermined grinding pressure value; II. If the vibration value measured by the vibration sensor after the cycle is greater than the predetermined value, the industrial control computer connects the first and second proportional air pressure valves to increase the pressure of the loading cylinder, and then detects the vibration value of the main frame to compare with whether it is greater than the predetermined value. If it is less than the predetermined value, the problem is solved and the cycle ends. If it is greater than the predetermined value and the problem is still not solved, the pressure of the loading cylinder is increased again, and the vibration value of the main frame is detected to compare with whether it is greater than the predetermined value, until it is less than the predetermined value. The pressure sensor obtains the loading end pressure value, which is used as an auxiliary input to enter the fuzzy PID control cycle for auxiliary control. The loading end pressure value cannot exceed the predetermined grinding pressure value. I and II can be performed simultaneously. Ⅲ If the vibration value measured by the vibration sensor after the cycle is greater than the predetermined value, and the problem is still not solved, the industrial control computer connects to the motor drive control system, changes the motor drive damping and stiffness, and then detects the vibration value of the main frame to compare with whether it is greater than the predetermined value. If it is less than the predetermined value, the problem is solved and the cycle ends. If it is greater than the predetermined value and the problem is still not solved, the damping and stiffness of the motor drive control system are changed again, and the vibration value of the main frame is detected to compare with whether it is greater than the predetermined value, until it is less than the predetermined value. IV. If the vibration value measured by the vibration sensor after the cycle is greater than the predetermined value, and the problem is still not solved, the industrial control computer changes the damping and stiffness of the vibration isolator through the third air proportional pressure valve and the variable stiffness damping vibration isolator, and then detects the vibration value of the main frame to compare with whether it is greater than the predetermined value. If it is less than the predetermined value, the problem is solved and the cycle ends. If it is greater than the predetermined value and the problem is still not solved, the damping and stiffness of the vibration isolator are changed again, and the vibration value of the main frame is detected to compare with whether it is greater than the predetermined value, until it is less than the predetermined value. III. Steps III and IV can be performed simultaneously. V. If the vibration value measured by the vibration sensor after the cycle is greater than the predetermined value, and the problem is still not solved, change the design parameters of the main frame, change the stiffness and damping of the main frame, and then detect the vibration value of the machine tool body to compare whether it is greater than the predetermined value; if it is greater than the predetermined value, continue to change the design parameters of the main frame, change the stiffness and damping of the main frame; if it is less than the predetermined value, the problem is solved and the cycle ends. VI. If the vibration value measured by the vibration sensor after the cycle is greater than the predetermined value and the problem is still not solved, improve the accuracy of the key components, and then detect the vibration value of the main frame to compare whether it is greater than the predetermined value. If it is greater than the predetermined value, continue to improve the accuracy of the key components. If it is less than the predetermined value, the problem is solved and the cycle ends. V and VI can be performed simultaneously.

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