Pulse air supply type air floatation device and air floatation control method

Abstract

The application relates to the field of semiconductor equipment, and provides a pulse air supply type air floating device and an air floating control method. The air floating device comprises a base, an air floating plate, a pulse electromagnetic valve array, a sensor and a controller. The air floating plate is arranged on the base, and the air floating plate is provided with an air hole array. The pulse electromagnetic valve array is arranged in the base, and the outlet of each pulse electromagnetic valve is in fluid connection with one or more air outlets in the air hole array. At least one sensor is configured to detect floating state information of a glass substrate in real time. The floating state information comprises at least one of height, vibration frequency and phase. The controller is in signal connection with the at least one sensor and the pulse electromagnetic valve array. The controller is configured to control the pulse electromagnetic valve array to work in a preset pulse mode based on the floating state information, so as to adjust the rigidity and thickness of the air film between the glass substrate and the air floating plate.

Description

Technical Field

[0001] This application relates to the field of semiconductor equipment, and in particular to a pulse-supply type air flotation device and air flotation control method. Background Technology

[0002] As a highly efficient and precise tool for suspension transportation and positioning, air flotation platforms have a wide range of applications. From industrial manufacturing to laboratory research, from material transfer to wastewater treatment, air flotation platforms have demonstrated their powerful functionality and adaptability.

[0003] Existing glass air flotation systems form an air film through continuous air supply. Without a pre-tightening system, the air film's stiffness is limited, failing to effectively resist vibrations from the equipment foundation. This leads to slight glass swaying, affecting detection accuracy. Due to the unique characteristics of the glass substrate, magnetic pre-tightening is not possible; instead, a negative pressure adsorption force is generated by integrating a vacuum adsorption chamber into the air outlet array. However, this solution requires a forced increase in the air supply pressure to over 0.8 MPa, resulting in a significant increase in gas flow. Furthermore, the continuous air supply mode leads to substantial waste of compressed air. While the air film formed by continuous air supply can reduce the impact of high-frequency vibrations on the glass substrate, it is ineffective against low-frequency vibrations. Summary of the Invention

[0004] This application aims to improve at least one technical problem in the background art.

[0005] This application provides a pulse-supply type air flotation device, which includes a base, an air flotation plate, a monitoring component, and an air jet component; The base is provided with multiple air passages, each having an inlet and an outlet that are interconnected. An air flotation plate is disposed on the base, and the surface of the air flotation plate is provided with a plurality of air outlet holes, each of the air outlet holes being connected to the air outlet end of an air passage. The monitoring component includes multiple sensors disposed on the air flotation plate for detecting the floating state information of the glass substrate when the glass substrate floats on the air flotation plate. The jet assembly includes a plurality of pulse solenoid valves disposed inside the base, and each pulse solenoid valve is connected to the inlet end of at least one of the air passages. The pulse solenoid valves are driven by a duty cycle adjustable pulse signal to generate a pulsed airflow.

[0006] According to some technical solutions of this application, the sensor is a laser displacement meter or a grating ruler.

[0007] According to some technical solutions of this application, there are four sensors, and the four sensors are respectively arranged along the outer edge of the air flotation plate.

[0008] According to some technical solutions of this application, the pulse solenoid valve is a piezoelectric high-speed valve.

[0009] This application also provides an air flotation control method for a glass substrate, which is applied to an air flotation control system for a glass substrate. The air flotation control system includes a control component and a pulse-supply type air flotation device as described above. The control component is electrically connected to a sensor and a pulse solenoid valve, respectively. The air flotation control method includes: Control the pulse solenoid valve to open at a preset duty cycle; When the pulse solenoid valve is opened, the status data of the air flotation device is acquired to determine the load status of the air flotation device. When the air flotation device is under load, the floating parameters of the glass substrate are obtained according to a preset time interval to obtain a set of floating parameters. Data is extracted from the set of floating parameters to obtain height information data and vibration component data; The steady-state duty cycle data is calculated based on the altitude information data, and the first pulse solenoid valve control command is generated. The vibration component data is analyzed and processed to generate an inverse pulse sequence; The steady-state duty cycle data and the inverted pulse sequence are superimposed to generate the second pulse solenoid valve control command.

[0010] According to some technical solutions of this application, the step of obtaining the state data of the air flotation device and determining the load state of the air flotation device specifically includes: Acquire the status data of the air flotation device to obtain the real-time height data and duration data of the glass substrate; Determine whether the height data is equal to or greater than the preset no-load height threshold and whether the duration data is less than the preset duration range; If the height data is equal to or greater than the preset no-load height threshold and the duration data is less than the preset duration range, then the air flotation device is determined to be in a no-load state. If the height data is less than the preset no-load height threshold and the duration data is greater than the preset duration range, then the air flotation device is determined to be in a loaded state.

[0011] According to some technical solutions of this application, the step of analyzing and processing the vibration component data to generate an inverse pulse sequence includes: The vibration component data is analyzed and extracted to obtain vibration frequency data and phase data; The vibration frequency and phase data are denoised using a preset control algorithm to generate an inverse pulse sequence.

[0012] According to some technical solutions of this application, the step of calculating steady-state duty cycle data based on altitude information data and generating a first pulse solenoid valve control command includes: Generate real-time average altitude based on altitude information data; The real-time average height is calculated based on a preset PID control algorithm and a preset target height to generate steady-state duty cycle data. The first pulse solenoid valve control command is generated based on the steady-state duty cycle data.

[0013] According to some technical solutions of this application, after the pulse solenoid valve is opened, the status data of the air flotation device is acquired, and the load status of the air flotation device is determined, the following steps are taken: If the air flotation device is in an unloaded state, a third pulse solenoid valve control command is generated to control the pulse solenoid valve to close. If the air flotation device is in a static load state, a fourth pulse solenoid valve control command is generated to control the pulse solenoid valve to reduce to a preset state.

[0014] According to some technical solutions of this application, when the air flotation device is under load, after obtaining the floating parameters of the glass substrate according to a preset time interval to obtain the floating parameter set, the method further includes: The floating parameter set was extracted and analyzed to obtain the position and deformation data of the glass substrate; Determine whether the deformation data is greater than the preset deformation threshold. If it is, generate the fifth pulse solenoid valve control command based on the position data.

[0015] The pulse-supply air flotation device provided in this application has at least the following beneficial effects: by providing a pulse solenoid valve, the pulse-supply can increase the stiffness of the air film without using negative pressure pre-tightening, and the air film thickness can be quickly adjusted by adjusting the duty cycle to meet the different requirements of different substrate sizes and different operating conditions, thereby reducing the complexity and cost of the equipment. Attached Figure Description

[0016] Figure 1 A top view schematic diagram of the glass substrate air flotation device provided in the embodiments of this application; Figure 2 This is a cross-sectional schematic diagram of the glass substrate air flotation device provided in the embodiments of this application; Figure 3 This is one of the flowcharts for the air flotation control method provided in the embodiments of this application; Figure 4 The second flowchart of the air flotation control method provided in the embodiments of this application; Figure 5 The third flowchart of the air flotation control method provided in the embodiments of this application; Figure 6 The fourth flowchart of the air flotation control method provided in the embodiments of this application; Figure 7The fifth flowchart of the air flotation control method provided in the embodiments of this application; Figure 8 The sixth flowchart is a representation of the air flotation control method provided in the embodiments of this application.

[0017] In the attached diagram: 100-base; 200-air float plate; 210-air passage; 300-sensor; 400-pulse solenoid valve; 220-air outlet. Detailed Implementation

[0018] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0019] In the description of this application, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation or be constructed or operated in a specific orientation. Therefore, they should not be construed as limiting the present invention.

[0020] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0021] The following is combined Figures 1 to 8 Embodiments of the present invention will be described.

[0022] As LCD and OLED display technologies evolve towards larger glass substrates, measurement and testing equipment widely adopts air-float platforms to meet micron-level precision requirements. Traditional continuous air supply modes have limited air film stiffness, failing to effectively resist vibrations in the equipment base, leading to slight glass swaying and affecting testing accuracy. To improve the accuracy and load capacity of air-float platforms, the stiffness of the air film needs to be increased. Traditional air-float platforms increase air film stiffness by applying pre-tension to the glass plate. For example, integrating a vacuum adsorption chamber into the air outlet array utilizes negative pressure to enhance the attraction between the glass and the base. However, this method increases the supply pressure and airflow, amplifying low-frequency vibrations transmitted to the glass. Simultaneously, the vacuum piping system significantly increases the structural complexity of the equipment. Furthermore, increasing the floating height during glass substrate loading and unloading ensures smooth handling; reducing the floating height during measurement and testing ensures measurement accuracy. Therefore, air-float platforms are typically divided into high-speed air-float and precision air-float areas.

[0023] Existing glass air flotation systems form an air film through continuous air supply. Without a pre-tightening system, the air film's stiffness is limited, failing to effectively resist vibrations from the equipment foundation, leading to slight glass swaying and affecting detection accuracy. Due to the unique characteristics of the glass substrate, magnetic pre-tightening is not possible; instead, negative pressure adsorption is generated by integrating a vacuum adsorption chamber into the air outlet array. However, this solution requires forcibly increasing the air supply pressure to over 0.8 MPa, resulting in a significant increase in gas flow. Continuous air supply leads to substantial waste of compressed air, especially when the glass is stationary or moving at low speeds, with unnecessary continuous air supply severely reducing system energy efficiency. While the air film formed by traditional continuous air supply methods can effectively reduce the impact of high-frequency equipment vibrations on the glass substrate, it is ineffective against low-frequency vibrations.

[0024] Based on the above, this application provides a pulse-supply air flotation device, which includes a base 100, an air flotation plate 200, a monitoring component, and an air jet component; The base 100 is the main support of the device. The base 100 is provided with multiple air passages 210, and the air passages 210 have interconnected air inlet and air outlet. An air flotation plate 200 is disposed on the base 100, and the upper working surface of the air flotation plate 200 is used to support the glass substrate. The surface of the air flotation plate 200 is provided with a plurality of air outlets 220, each of the air outlets 220 being connected to the air outlet end of an air passage 210; that is, the air flotation plate 200 is provided with an array of air outlets, and the inlet of each air outlet in the array is connected to an air passage 210 inside the base 100.

[0025] The monitoring component includes multiple sensors 300, which are disposed on the air flotation plate 200 and are used to detect the floating state information of the glass substrate when the glass substrate floats on the air flotation plate. Optionally, there are four sensors 300. The four sensors 300 are arranged along the outer edge of the air-float plate 200, that is, arranged in the four corner areas of the platform. They can form a four-point detection area on the air-float plate 200. The complete three-dimensional attitude of a rectangular object can be uniquely determined by the four points, including three translations of X, Y and Z and two tilts around the X and Y axes. This can be used to measure the flatness, floating height and micro-vibration of the glass substrate in real time.

[0026] For example, when the readings of two diagonally opposite sensors 300 are detected to increase or decrease simultaneously, the controller can easily determine whether it is a pure lifting motion or a gyratory motion. In addition, depending on the measurement accuracy required, the number of sensors 300 can be increased and arranged in the center of the platform edge or in specific key areas.

[0027] Among them, sensor 300 can be a non-contact measurement laser displacement meter or optical grating ruler. The laser displacement meter directly measures the distance change by emitting a laser to the lower surface of the glass and receiving the reflected light; the optical grating ruler obtains high-precision position information by reading a scale installed on the edge of the glass or an additional device. Compared to sensor 300, which has excessive delay, both of these have micron-level or even submicron-level resolution, capable of clearly capturing high-frequency, minute changes in the air film thickness, providing high-quality input signals for active control. The sampling frequency of these two technologies can reach tens or even hundreds of kHz, far exceeding the vibration frequencies typically below several hundred Hz that air-bearing platforms need to suppress. This ensures that the control system can capture vibration waveforms in real time.

[0028] The jet assembly includes a plurality of pulse solenoid valves 400 disposed inside the base 100, and each pulse solenoid valve 400 is connected to the air inlet end of at least one of the air passages 210. The pulse solenoid valves 400 are driven by a pulse signal with adjustable duty cycle to form a pulsed airflow.

[0029] The pulse solenoid valves 400 are embedded inside the base 100 in an M×N matrix. The outlet of each pulse solenoid valve 400 is directly connected to one or more air outlets 220. The number of solenoid valves in the air flotation device can be adjusted as needed, i.e., set according to the size of the glass substrate, the required control accuracy, cost budget, and system complexity requirements. Alternatively, the pulse solenoid valves 400 can be piezoelectric high-speed valves, i.e., the jet assembly consists of multiple independently controlled piezoelectric high-speed valves.

[0030] In actual assembly, for example, 81 pulse solenoid valves 400 can be arranged in 9 rows × 9 columns. Specifically, for larger substrates, such as G10.5 or larger, 11×11, 13×13, or more valves can be used to maintain the same control accuracy. For applications with lower accuracy requirements or cost sensitivity, a 7×7, 5×5, or fewer valves can be used as a simplification solution. Thus, by uniformly arranging the valve array within the plane of the base 100, a zoned controllable air supply system covering the entire air-bearing plane is formed.

[0031] In some embodiments, the pulse solenoid valves 400 array is in the form of an M×N matrix and embedded inside the base 100. Understandably, since the air-floating platform needs to provide uniform support force to the glass, the M×N configuration of the pulse solenoid valves 400 allows for a more symmetrical and uniformly distributed valve array. A symmetrical and uniformly distributed valve array is most conducive to forming a stable and consistent air film stiffness across the entire plane, avoiding uneven stress on the glass plate due to uneven valve distribution, thus preventing unnecessary stress or deformation. A square or near-square array layout best ensures effective coverage of the rectangular glass plate, allowing for effective control of the four corners and edges.

[0032] Install the air flotation plate 200 on the base 100, ensuring that the air hole array of the air flotation plate 200 corresponds one-to-one with the outlet of the pulse solenoid valve 400 array inside the base 100 and achieves fluid connection; install at least one sensor 300 at the designated position of the air flotation platform, and complete the signal connection debugging between the controller and the sensor 300 and the pulse solenoid valve 400 array.

[0033] In actual configuration, the controller is signal-connected to at least one sensor 300 and the pulse solenoid valve 400 array. The controller is configured to control the pulse solenoid valve 400 array to operate in a preset pulse mode based on the floating state information, so as to adjust the stiffness and thickness of the air film between the glass substrate and the air flotation plate 200.

[0034] In some embodiments, the pulse solenoid valve 400 is a piezoelectric high-speed valve. The piezoelectric high-speed valve is used as the pulse solenoid valve 400 and is embedded in the base 100 in an M×N matrix. The inlet of each piezoelectric high-speed valve is connected to an air source, and the outlet is fluidly connected to the air outlet 220 of the air float plate 200, thus completing the assembly and debugging of the valve group and the air circuit.

[0035] When the device is working, the controller sends pulse control signals to the piezoelectric high-speed valve. The piezoelectric element of the valve deforms rapidly under the action of the voltage signal, realizing the high-speed opening and closing of the valve, thereby generating a high-frequency pulsed airflow. The controller controls the valve's opening duration and period by adjusting the pulse signal parameters output to the piezoelectric high-speed valve, thereby changing the intensity and frequency of the pulsed airflow. For example, in the precision measurement stage, the pulse frequency is increased and the duty cycle is decreased to form a high-rigidity, thin-film gas; in the loading and unloading stage, the pulse frequency is decreased and the duty cycle is increased to form a thicker gas film.

[0036] This application also provides an air flotation control method for a glass substrate, which is applied to an air flotation control system for a glass substrate. The air flotation control system includes a control component and a pulse-supply type air flotation device as described above. The control component is electrically connected to the sensor 300 and the pulse solenoid valve 400, respectively. The air flotation control method includes: S100 controls the pulse solenoid valve to open with a preset duty cycle; Upon startup, the controller sends an opening command to all pulse solenoid valves of the air flotation device, causing all valves to open at 100% duty cycle. At this point, all pulse solenoid valves are fully open, and compressed gas is vertically sprayed onto the lower surface of the glass substrate through an array of air outlets on the air flotation plate. The gas rapidly accumulates in the gap between the glass and the air flotation plate, forming a continuous and uniform initial gas film. Regardless of the size and weight of the glass substrate, the maximum gas supply intensity ensures that the gas film covers the bottom surface of the glass within 3-5 seconds, lifting the glass substrate from a contact state to initial floating. It should be noted that, in this context, the pulse solenoid valve control command controls the pulse solenoid valves to supply gas at the corresponding duty cycle to adjust the gas film thickness between the glass substrate and the air flotation plate.

[0037] Therefore, continuous gas supply with a 100% duty cycle can quickly accumulate sufficient gas pressure between the glass and the air-float plate, forming a uniform gas film. This continuous gas supply mode is a traditional and mature method for gas film formation. In the unknown state after system startup, it can minimize direct contact between the glass and the air-float plate, providing a safe and known initial operating state for subsequent control. Furthermore, its stability is unaffected by differences in the size and specifications of the glass substrate.

[0038] S200: When the pulse solenoid valve is opened, the status data of the air flotation device is acquired to determine the load status of the air flotation device. Specifically, after the pulse solenoid valve is opened, sensors installed at the four corners of the air-floating platform, such as laser displacement gauges or grating rulers, collect data in real time to generate real-time height data of the glass substrate and the duration of that height.

[0039] In some embodiments, in step S200, acquiring the state data of the air flotation device and determining the load state of the air flotation device specifically includes: S210, acquire the status data of the air flotation device, and obtain the real-time height data and duration data of the glass substrate; S220, determine whether the height data is equal to or greater than the preset no-load height threshold and whether the duration data is less than the preset duration range; S230, if the height data is equal to or greater than the preset no-load height threshold and the duration data is less than the preset duration range, then the air flotation device is determined to be in a no-load state. S240, if the height data is less than the preset no-load height threshold and the duration data is greater than the preset duration range, then the air flotation device is determined to be in a loaded state.

[0040] Specifically, the controller calls upon preset no-load height thresholds and preset duration ranges. The no-load height threshold is calibrated and set before the device leaves the factory; it represents the distance measured by the sensor when the platform is empty. The preset duration range is a preset value, such as 0.1-0.5 seconds. The collected data is compared and judged. If the real-time height data is equal to or greater than the no-load height threshold, and the duration data is less than the preset duration range, it is determined to be in a no-load state. If the real-time height data is less than the no-load height threshold, and the duration data is greater than the preset duration range, it is determined to be in a loaded state. The preset duration range can filter out accidental operations such as a hand brushing across the platform or small debris falling.

[0041] In some alternative embodiments, in step S200, after the pulse solenoid valve is opened, the status data of the air flotation device is acquired, and the load status of the air flotation device is determined, the following steps are included: S211, If ​​the air flotation device is in an unloaded state, a third pulse solenoid valve control command is generated to control the pulse solenoid valve to close. S212, if the air flotation device is in a static load state, a fourth pulse solenoid valve control command is generated to control the pulse solenoid valve to reduce to a preset state. Thus, different pulse solenoid valve control strategies correspond to different load states. When there is no load, no air supply is required, and closing the pulse solenoid valve saves energy to the greatest extent. Under static load, it is not necessary to maintain a high-precision air film; only a low duty cycle, such as maintaining a 30% duty cycle, is needed to maintain the foundation's buoyancy. Static load refers to the idle stage when there is a load but no loading / unloading or stable detection is required. Furthermore, during the unloading stage, the central pulse valve is opened, for example, at a 40% duty cycle, to provide low-pressure air supply, preventing the glass substrate from impacting the air flotation plate due to rapid separation.

[0042] Therefore, load determination is achieved by utilizing the height change characteristics and state stability differences of the air film after it is compressed. Based on actual sensor data, the load state determination can be automated without human intervention, thus improving the accuracy of load state identification.

[0043] S300: When the air flotation device is under load, it acquires the floating parameters of the glass substrate at preset time intervals to obtain a floating parameter set. When the controller determines that the air flotation device is under load, it triggers the sensors to acquire the floating parameters of the glass substrate at preset time intervals. The same set of sensors simultaneously completes multi-parameter acquisition. The laser displacement meter directly measures the absolute distance from the sensor probe to the lower surface of the glass, and the grating ruler measures the displacement of the glass relative to a fixed reference point. The parameters acquired by the sensors include height, vibration frequency, amplitude, etc. All parameters are summarized to form a floating parameter set and transmitted to the controller.

[0044] In some embodiments, in step S300, after obtaining the floating parameters of the glass substrate according to a preset time interval and obtaining the floating parameter set when the air flotation device is under load, the method further includes: S310, extract and analyze the floating parameter set to obtain the position data and deformation data of the glass substrate; S320: Determine whether the deformation data is greater than the preset deformation threshold. If it is, generate the fifth pulse solenoid valve control command based on the position data.

[0045] Specifically, since large-area glass substrates are prone to central protrusions due to uneven gas film pressure, positional data is used to locate the coverage area of ​​the glass substrate on the air-bearing platform. Deformation data is then used to determine if central protrusion deformation exists. If the deformation exceeds the system's allowable accuracy threshold (e.g., deformation > 5 μm), it is identified as a large-area glass substrate. Furthermore, by reducing the duty cycle of the pulse solenoid valve in the central region and maintaining the duty cycle of the pulse solenoid valve in the edge region, the gas film pressure can be balanced, offsetting the central protrusion deformation of the glass substrate and achieving correction of the large-area glass substrate.

[0046] The central region refers to the area covered by the glass substrate projected onto the air-bearing plate, and is a certain safe distance from the glass edge, for example, 50-150mm. The edge region refers to the edge region of the glass substrate projected onto the air-bearing plate, excluding the central region. By adjusting the duty cycle of the pulse valve in the central region to be lower than that in the edge region, the deformation of the central protrusion caused by uneven pressure is counteracted.

[0047] Therefore, by continuously collecting the parameter set, the real-time changes of glass floating can be obtained, thus providing data for subsequent air film thickness adjustment and vibration suppression.

[0048] S400 extracts data from the floating parameter set to obtain height information data and vibration component data; after receiving the floating parameter set, it extracts data from the collected dataset, including height information data reflecting the thickness of the air film and vibration component data reflecting the vibration state of the glass.

[0049] S500 calculates steady-state duty cycle data based on altitude information data and generates the first pulse solenoid valve control command. Specifically, the controller first analyzes the extracted height information data to calculate the real-time average height of the glass substrate. Then, it calls a preset PID control algorithm and a target height. During the precision measurement stage, the target height is a specific value between 3-20 μm, and during the loading and unloading stage, it is a specific value between 50-200 μm. The deviation between the real-time average height and the target height is calculated to generate steady-state duty cycle data, with a duty cycle range of 5%-95%, adjusted according to the size and weight of the glass substrate. Finally, based on this steady-state duty cycle data, a first pulse solenoid valve control command is generated to control the air supply intensity of the pulse solenoid valve, thereby stabilizing the glass substrate at the target floating height and meeting the height requirements of different process stages.

[0050] In some embodiments, in step S500, calculating the steady-state duty cycle data based on the altitude information data and generating the first pulse solenoid valve control command includes: S510 generates real-time average altitude based on altitude information data; S520 calculates the real-time average height based on a preset PID control algorithm and a preset target height to generate steady-state duty cycle data; S530 generates the first pulse solenoid valve control command based on the steady-state duty cycle data.

[0051] Specifically, a preset PID control algorithm and target height are invoked to calculate the difference between the real-time average height and the target height, dynamically generating steady-state duty cycle data. This steady-state duty cycle data is then converted into a control signal recognizable by the pulse solenoid valve, generating the first pulse solenoid valve control command. Operating with a millisecond-level response speed, the duty cycle of the pulse valve is dynamically adjusted to maintain the stability of the air film thickness.

[0052] S600 analyzes and processes vibration component data to generate inverse pulse sequences; Specifically, the controller analyzes and processes the extracted vibration component data, first separating and extracting the vibration frequency and phase data. Then, it calls a preset control algorithm, such as based on existing FFT and PID control algorithms, to perform noise reduction processing on the vibration frequency and phase data, filtering out environmental interference signals. Finally, based on the processed frequency and phase data, it generates an inverse pulse sequence of the original vibration.

[0053] The method for generating the inverse pulse sequence is an existing active noise reduction process.

[0054] First, the controller samples the altitude signal transmitted from the sensor. The time-domain data is then converted to a frequency-domain signal using a Fourier transform (FFT) algorithm; the highest peak in the frequency spectrum corresponds to the main disturbance frequency fv.

[0055] Next, an adaptive filtering algorithm is used to calculate the phase φ and amplitude A of the current vibration signal in real time. Finally, the instantaneous value of the reverse pulse is calculated as -A. sin(2) π fv The calculated inverted signal value (t+φ) is converted into the duty cycle of the PWM signal using pulse width modulation (PWM) technology. The frequency of this PWM signal is much higher than the vibration frequency fv. The high-frequency characteristics of the piezoelectric high-speed valve in this embodiment can achieve this level of accuracy. The final duty cycle of the driving pulse valve is the output steady-state duty cycle plus the reverse PWM duty cycle offset. Simultaneously, the controller ensures that the final duty cycle is controlled within the effective range of 0% to 100%.

[0056] In some embodiments, step S600, analyzing and processing the vibration component data to generate an inverse pulse sequence, includes: S610 analyzes and extracts vibration component data to obtain vibration frequency data and phase data; The S620 uses a preset control algorithm to denoise the vibration frequency and phase data, generating an inverse pulse sequence.

[0057] The S700 superimposes steady-state duty cycle data and the inverse pulse sequence to generate a second pulse solenoid valve control command. The controller superimposes the obtained steady-state duty cycle data with the generated inverse pulse sequence, ensuring the final duty cycle is within the effective range of 0%-100%. Based on the superimposed duty cycle data, a second pulse solenoid valve control command is generated and sent to the pulse solenoid valve array. This commands the solenoid valve to supply air according to the specified duty cycle, achieving synchronous control of gas film thickness adjustment and vibration suppression.

[0058] The preferred embodiments of the present invention have been described in detail above, but the present disclosure is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention, and these equivalent modifications or substitutions are all included within the scope defined by the claims of the present disclosure.

Claims

1. A pulse-supply type air flotation device, characterized in that: include: The base has multiple air passages inside, and the air passages have interconnected air inlet and air outlet ends; An air flotation plate is disposed on the base, and the surface of the air flotation plate is provided with a plurality of air outlet holes, each of the air outlet holes being connected to the air outlet end of an air passage. The monitoring component includes multiple sensors disposed on the air flotation plate for detecting the floating state information of the glass substrate when the glass substrate floats on the air flotation plate. The jet assembly includes multiple pulse solenoid valves in an M×N matrix configuration. The multiple pulse solenoid valves are located inside the base, and each pulse solenoid valve is connected to the inlet end of at least one of the air passages. The pulse solenoid valves are driven by a pulse signal with an adjustable duty cycle to form a pulsed airflow that achieves synchronous control for adjusting the air film thickness and suppressing vibration. The control method includes: controlling the pulse solenoid valve to open with a preset duty cycle; after the pulse solenoid valve opens, acquiring the status data of the air flotation device to determine the load state of the air flotation device; when the air flotation device is under load, acquiring the floating parameters of the glass substrate according to a preset time interval to obtain a floating parameter set; extracting data from the floating parameter set to obtain height information data and vibration component data; calculating the steady-state duty cycle data based on the height information data and generating a first pulse solenoid valve control command; analyzing and processing the vibration component data to generate an inverse pulse sequence; and superimposing the steady-state duty cycle data and the inverse pulse sequence to generate a second pulse solenoid valve control command.

2. The pulse-supply air flotation device according to claim 1, characterized in that: The sensor is a laser displacement meter or a grating ruler.

3. The pulse-supply air flotation device according to claim 1, characterized in that: There are four sensors, which are arranged along the outer edge of the air flotation plate.

4. The pulse-supply air flotation device according to claim 1, characterized in that: The pulse solenoid valve is a piezoelectric high-speed valve.

5. A flotation control method, applied to the flotation control system of an air flotation device, the air flotation control system comprising a control component and a pulse-supply type air flotation device as described in any one of claims 1-4, wherein the control component is electrically connected to a sensor and a pulse solenoid valve respectively, characterized in that: Air flotation control methods include: Control the pulse solenoid valve to open at a preset duty cycle; When the pulse solenoid valve is opened, the status data of the air flotation device is acquired to determine the load status of the air flotation device. When the air flotation device is under load, the floating parameters of the glass substrate are obtained according to a preset time interval to obtain a set of floating parameters. Data is extracted from the set of floating parameters to obtain height information data and vibration component data; The steady-state duty cycle data is calculated based on the altitude information data, and the first pulse solenoid valve control command is generated. The vibration component data is analyzed and processed to generate an inverse pulse sequence; The steady-state duty cycle data and the inverted pulse sequence are superimposed to generate the second pulse solenoid valve control command.

6. The air flotation control method according to claim 5, characterized in that: The process of acquiring the status data of the air flotation device and determining its load status specifically includes: Acquire the status data of the air flotation device to obtain the real-time height data and duration data of the glass substrate; Determine whether the height data is equal to or greater than the preset no-load height threshold and whether the duration data is less than the preset duration range; If the height data is equal to or greater than the preset no-load height threshold and the duration data is less than the preset duration range, then the air flotation device is determined to be in a no-load state. If the height data is less than the preset no-load height threshold and the duration data is greater than the preset duration range, then the air flotation device is determined to be in a loaded state.

7. The air flotation control method according to claim 5, characterized in that: The analysis and processing of vibration component data to generate an inverse pulse sequence includes: The vibration component data is analyzed and extracted to obtain vibration frequency data and phase data; The vibration frequency and phase data are denoised using a preset control algorithm to generate an inverse pulse sequence.

8. The air flotation control method according to claim 5, characterized in that: The step of calculating the steady-state duty cycle data based on altitude information data and generating the first pulse solenoid valve control command includes: Generate real-time average altitude based on altitude information data; The real-time average height is calculated based on a preset PID control algorithm and a preset target height to generate steady-state duty cycle data. The first pulse solenoid valve control command is generated based on the steady-state duty cycle data.

9. The air flotation control method according to claim 5, characterized in that: After the pulse solenoid valve opens, the status data of the air flotation device is acquired, and the load status of the air flotation device is determined, including: If the air flotation device is in an unloaded state, a third pulse solenoid valve control command is generated to control the pulse solenoid valve to close. If the air flotation device is in a static load state, a fourth pulse solenoid valve control command is generated to control the pulse solenoid valve to reduce to a preset state.

10. The air flotation control method according to claim 5, characterized in that: When the air flotation device is under load, after obtaining the floating parameters of the glass substrate according to a preset time interval to obtain the floating parameter set, the method further includes: The floating parameter set was extracted and analyzed to obtain the position and deformation data of the glass substrate; Determine whether the deformation data is greater than the preset deformation threshold. If it is, generate the fifth pulse solenoid valve control command based on the position data.

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