Stone removing machine with stone removal loss rate closed-loop control function

Abstract

The invention discloses a stone removing machine with a stone removal loss rate closed-loop control function. Comprising a machine frame, a screen box obliquely arranged on the machine frame, a vibration mechanism driving the screen box to vibrate in a reciprocating mode, an air suction pipe arranged at the top of the screen box, a feeding pipe arranged at the top of the screen box and located behind the air suction pipe, a discharging opening formed in the front side of the screen box and a stone discharging opening formed in the rear side of the screen box. The material returning plate assembly is installed in the screen box and located between the screen mesh and the stone discharging port, the detection unit is arranged to monitor the proportion of stones and grains in materials discharged from the stone discharging port in real time, the inclination angle of a material returning plate body is automatically adjusted in combination with the controller, and closed-loop control over the stone discharging loss rate is achieved. According to the control mode, the material returning amount can be automatically optimized according to the actual working condition, and the grain loss is effectively reduced on the premise that the stone removing effect is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of grain processing equipment technology, specifically to a destoner with a closed-loop control function for stone loss rate. Background Technology

[0002] Destoners are commonly used equipment in the grain processing industry to separate heavy impurities such as stones from grain particles. Their working principle is mainly based on the difference in specific gravity and suspension velocity of the materials. Through the reciprocating vibration of the screen box and the action of airflow, the grain and stones are separated into layers. The stones move upwards along the screen surface and are discharged from the stone discharge port, while the grain flows out from the discharge port.

[0003] Traditional destoners typically have an adjustable-angle return plate at the discharge port to control the amount of grain carried out during the stone discharge process (i.e., the stone loss rate). Operators need to manually adjust the angle of the return plate based on experience to achieve a balance between destone removal efficiency and grain loss. However, this manual adjustment method has the following problems: First, the adjustment is lagging and cannot be adjusted in real time according to changes in material; second, it relies on the operator's experience, resulting in low precision and easily leading to excessive grain loss or incomplete stone removal; third, it lacks quantitative monitoring and feedback control of the stone loss rate, making it difficult to achieve stable and efficient destone removal operations. Summary of the Invention

[0004] The present invention aims to solve the above-mentioned technical problems in the control of stone discharge loss of existing destoners, and to provide a destoner that can automatically adjust the angle of the return plate and realize closed-loop control of the stone discharge loss rate.

[0005] To achieve the above objectives, the present invention provides a destoner with a closed-loop control function for stone loss rate, comprising a frame, a screen box inclinedly mounted on the frame, a vibration mechanism for driving the screen box to reciprocate, an air suction pipe mounted on the top of the screen box, a feed pipe mounted on the top of the screen box and located behind the air suction pipe, a discharge port mounted on the front side of the screen box, and a stone discharge port mounted on the rear side of the screen box. The screen box contains a screen mesh, and further comprises:

[0006] The return plate assembly is installed inside the screen box and located above the rear end of the screen, including a return plate body rotatably mounted on the side plate of the screen box and an electric actuator that drives the return plate body to rotate around a first rotating shaft. The detection unit, located at the stone discharge port, is used to detect the proportion of stones and grains in the material discharged from the stone discharge port in real time and generate a corresponding loss rate signal. The controller is electrically connected to the electric actuator and the detection unit respectively. The controller is configured to automatically send adjustment commands to the electric actuator to change the tilt angle of the return plate body based on the comparison result of the received loss rate signal and the preset threshold.

[0007] Furthermore, the detection unit includes: The image acquisition module is used to acquire images of the material being discharged from the stone discharge port in real time. The image analysis module, electrically connected to the image acquisition module, is used to analyze the acquired images, identify the pixel area ratio of stones and grains in the discharged material, and generate a loss rate signal based on the ratio.

[0008] Furthermore, the image analysis module has a built-in deep learning-based image recognition model for stones and grains, which is trained by multiple sets of sample images with pre-labeled stone and grain regions.

[0009] Furthermore, the controller is configured as follows: When the loss rate signal exceeds the preset upper limit threshold, a first adjustment command is sent to the electric actuator to drive the return plate body to rotate in the direction of increasing the amount of return material. When the loss rate signal is lower than the preset lower threshold, a second adjustment command is sent to the electric actuator to drive the return plate body to rotate in the direction of reducing the amount of return material.

[0010] Furthermore, an angle sensor is provided between the first rotating shaft and the side plate of the screen box. The angle sensor is electrically connected to the controller and is used to provide real-time feedback on the current angle position of the return plate body. The controller is configured to perform closed-loop control of the electric actuator based on the deviation between the current angle position and the target angle position.

[0011] Furthermore, the electric actuator is a stepper motor or a servo motor, and the output shaft of the stepper motor or servo motor is connected to the first rotating shaft of the return plate body.

[0012] Furthermore, it also includes: The airflow regulating assembly includes a damper plate that is rotatably mounted inside the air intake duct via a second rotating shaft.

[0013] Furthermore, it also includes: The linkage transmission mechanism is connected to the return plate body and the damper plate respectively. The linkage transmission mechanism is configured to drive the damper plate to rotate synchronously when the return plate body rotates around the first rotating shaft, so as to realize the synchronous adjustment of the tilt angle of the return plate body and the air intake volume of the suction pipe.

[0014] Furthermore, the linkage transmission mechanism includes: The first swing arm is fixedly connected to the end of the first rotating shaft of the return plate body; The second swing arm is fixedly connected to the end of the second rotating shaft of the damper plate; A connecting rod, one end of which is hinged to a first swing arm and the other end of which is hinged to a second swing arm; When the return plate body rotates, the first rotating shaft drives the first swing arm to swing, and the first swing arm drives the second swing arm to swing through the connecting rod, thereby driving the damper plate to rotate synchronously.

[0015] Furthermore, the first swing arm is provided with a plurality of hinge holes spaced apart along the length direction, and the end of the connecting rod can be selectively connected to any of the hinge holes to adjust the transmission ratio between the return plate body and the damper plate.

[0016] The beneficial effects of this invention include: 1. This invention achieves closed-loop control of the stone discharge loss rate by setting up a detection unit to monitor the ratio of stones to grains in the material discharged from the stone discharge port in real time, and by automatically adjusting the tilt angle of the return plate body with a controller. This control method can automatically optimize the return material amount according to the actual working conditions, effectively reducing grain loss while ensuring the stone removal effect.

[0017] 2. This invention uses a linkage transmission mechanism to drive the return plate body and the damper plate. When the return plate body rotates, it synchronously drives the damper plate to rotate, realizing the coordinated adjustment of the return plate angle and the suction volume. This mechanical linkage structure does not require additional sensors and actuators, which simplifies the control system. At the same time, it ensures the coordinated matching of the return volume and the air volume, further optimizes the airflow distribution inside the screen box, and improves the stone removal efficiency and operational stability. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the destone destoner with closed-loop control function for stone loss rate according to the present invention. Figure 2 This is another state diagram of the destoner with closed-loop control function for stone loss rate of the present invention; Figure 3 This is a partial structural diagram of the destoner with closed-loop control function for stone loss rate according to the present invention. Figure 4 This is a circuit block diagram of the destone destoner with closed-loop control function for stone loss rate of the present invention; In the diagram: 1-Frame; 2-Screen box; 3-Vibration mechanism; 4-Suction pipe; 5-Feed pipe; 6-Discharge port; 7-Stone discharge port; 8-Screen; 9-Return plate assembly; 91-Return plate body; 911-First rotating shaft; 92-Electric actuator; 10-Detection unit; 11-Controller; 12-Angle sensor; 13-Airflow adjustment assembly; 131-Damper plate; 1311-Second rotating shaft; 14-Linkage transmission mechanism; 141-First swing arm; 1411-Hinge hole; 142-Connecting rod; 143-Second swing arm. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0020] Example 1 like Figure 1-2 As shown, this embodiment provides a destoner with a closed-loop control function for stone loss rate, including a frame 1, a screen box 2 inclinedly mounted on the frame 1, a vibration mechanism 3 driving the screen box 2 to reciprocate, an air suction pipe 4 mounted on the top of the screen box 2, a feed pipe 5 mounted on the top of the screen box 2 and located behind the air suction pipe 4, a discharge port 6 located on the front side of the screen box 2, and a stone discharge port 7 located on the rear side of the screen box 2. The screen box 2 contains a screen mesh 8. The bottom of the frame 1 is typically equipped with a vibration damping device (such as rubber damping pads or springs) to isolate the impact of the screen box 2 vibration on the foundation. The vibration mechanism 3 can be a vibrating motor or an eccentric shaft mechanism, causing the screen box 2 to reciprocate with a certain amplitude and frequency, promoting material stratification on the screen mesh 8. Grains in the material move towards the discharge port 6, while stones move towards the stone discharge port 7. The air suction pipe 4 is connected to an external fan to create an upward airflow inside the screen box 2, assisting in material stratification according to specific gravity.

[0021] As one of the core improvements of this invention, such as Figure 4 As shown, the destoner also includes a return plate assembly 9, a detection unit 10, and a controller 11.

[0022] The return plate assembly 9 is installed inside the screen box 2 and located above the rear end of the screen 8. The return plate assembly 9 includes a return plate body 91 and an electric actuator 92. The return plate body 91 has a rectangular plate structure, the width of which matches the internal width of the screen box 2. Its upper side is rotatably mounted between the two side plates of the screen box 2 via a first rotating shaft 911. The two ends of the first rotating shaft 911 are mounted on the side plates of the screen box 2 via bearings to ensure the flexibility of rotation. The lower side of the return plate body 91 is a free end, which can swing up and down around the first rotating shaft 911 under the drive of the electric actuator 92, thereby changing the gap between the return plate body 91 and the screen 8 and the tilt angle of the return plate body 91.

[0023] The electric actuator 92 is fixedly installed on the outer side of the side plate of the screen box 2, and its output shaft is connected to one end of the first rotating shaft 911 via a coupling or gear pair. In this embodiment, the electric actuator 92 is preferably a stepper motor, which has good open-loop position control capability and can accurately control the rotation angle according to the number of pulses. In another variation, the electric actuator 92 can also be a servo motor, which, together with an encoder, can achieve higher precision closed-loop position control. The control terminal of the stepper motor or servo motor is electrically connected to the controller 11, receiving pulse signals or analog signals from the controller 11, thereby driving the return plate body 91 to rotate to the target angle.

[0024] The detection unit 10 is located at the stone discharge port 7 and is used to detect the proportion of stones and grains in the material discharged from the stone discharge port 7 in real time, and generate a corresponding loss rate signal. The detection unit 10 includes an image acquisition module and an image analysis module. The image acquisition module is preferably an industrial-grade CMOS or CCD camera, equipped with an LED fill light, and is fixedly installed directly above or to the side of the stone discharge port 7, with the lens aimed at the material dropping area of ​​the stone discharge port 7 to ensure clear capture of the image of the material falling from the stone discharge port 7. To adapt to different lighting conditions, the camera can be configured with automatic exposure and white balance functions.

[0025] The image analysis module can be an embedded processing unit integrated into the camera, or a standalone industrial computer or a processing unit integrated with the controller 11. The image analysis module is electrically connected to the image acquisition module via a data cable or wirelessly. The image analysis module has a built-in deep learning-based image recognition model for stones and grains. This model is trained using multiple sets of sample images pre-labeled with stone and grain regions. The specific training process is as follows: First, a large number of image samples of materials from the stone discharge port 7 are acquired, and the stone and grain regions in the images are manually labeled at the pixel level using a labeling tool (such as LabelImg). Then, a convolutional neural network (CNN) architecture (such as U-Net, MaskR-CNN, etc.) is used for training, enabling the model to automatically identify and segment the stones and grains in the image. After training, the model can output the pixel area ratio of stones and grains in the image. The image analysis module generates a loss rate signal (e.g., "Current loss rate: 12.5%) based on the proportion of grain pixel area to the total material pixel area, and sends this signal to the controller 11 in real time.

[0026] In other embodiments, the detection unit 10 may also employ other sensor combinations, such as a near-infrared spectral sensor combined with a photoelectric counter, to distinguish between stones and grains through spectral characteristics and calculate the proportion of discharged quantities, thereby achieving real-time detection of the loss rate.

[0027] The controller 11 is a programmable logic controller (PLC) or an embedded microcontroller (such as an ARM series microcontroller), which is electrically connected to the electric actuator 92 and the detection unit 10, respectively. The controller 11 has preset upper and lower threshold values ​​for the loss rate, for example, the upper threshold is set to 15% and the lower threshold is set to 5%. These two threshold values ​​can be set on-site according to different grain types (such as wheat, rice, corn) and processing requirements.

[0028] The controller 11 is configured to automatically send adjustment commands to the electric actuator 92 based on the comparison result of the received loss rate signal and a preset threshold. The specific control logic is as follows: When the loss rate signal exceeds a preset upper limit threshold (e.g., grain content > 15%), it indicates that too much grain is being carried out of the discharge port 7, resulting in significant grain waste. At this time, the controller 11 sends a first adjustment command to the electric actuator 92 (e.g., N pulses of forward rotation), driving the return plate body 91 to rotate a certain angle in the direction of increasing the return amount. The so-called "direction of increasing the return amount" means that the free end of the return plate body 91 rotates towards the screen 8, reducing the gap between the return plate body 91 and the screen 8, and at the same time reducing the tilt angle of the return plate body 91. This intercepts more of the mixture about to be discharged from the discharge port 7 and guides it back to the front end of the screen 8 for further separation, thereby reducing the grain content in the discharge port.

[0029] When the loss rate signal is lower than the preset lower threshold (e.g., grain percentage < 5%), it indicates that too little grain is being discharged from the stone discharge port 7. This may mean that the return plate body 91 is over-intercepting, causing some stones to fail to be discharged in time, posing a risk of incomplete stone removal. At this time, the controller 11 sends a second adjustment command to the electric actuator 92 (e.g., reverse rotation N pulses), driving the return plate body 91 to rotate in the direction of reducing the amount of return material. The so-called "direction of reducing the amount of return material" means that the free end of the return plate body 91 rotates away from the screen 8, making the gap between the return plate body 91 and the screen 8 larger, and increasing the tilt angle of the return plate body 91, thereby allowing more material (including stones and a small amount of grain) to be discharged directly from the stone discharge port 7, ensuring that the stones are removed in time.

[0030] When the loss rate signal is between the upper and lower thresholds (e.g., 5% to 15%), the controller 11 does not issue an adjustment command and keeps the current angle of the return plate body 91 unchanged in order to maintain system stability.

[0031] Through the above closed-loop control mechanism, the stone discharge loss rate is always maintained within a preset reasonable range, realizing the automatic optimization of the stone discharge process of the destoner.

[0032] To further improve the accuracy and response speed of the angle adjustment of the return plate body 91, an angle sensor 12 is provided between the return plate body 91 and the side plate of the screen box 2. The angle sensor 12 can be a non-contact magnetic encoder or a conductive plastic potentiometer. Its fixed end is installed on the side plate of the screen box 2, and its rotating end is linked with the first rotating shaft 911 to detect the rotation angle of the first rotating shaft 911 in real time, thereby providing feedback on the current angle position of the return plate body 91. The angle sensor 12 is electrically connected to the controller 11, transmitting the real-time angle signal to the controller 11. The controller 11 uses a PID (proportional-integral-derivative) control algorithm to calculate the required drive quantity (such as the number of pulses of a stepper motor) of the electric actuator 92 based on the deviation between the current angle position and the target angle position, and outputs a control signal. The angle closed-loop control and the loss rate closed-loop control form a cascade control structure: the outer loop is the loss rate closed loop, which determines the target angle based on the loss rate deviation; the inner loop is the angle closed loop, which precisely drives the electric actuator 92 based on the angle deviation, thereby ensuring that the return plate body 91 reaches the target angle quickly and accurately, and improving the dynamic response performance of the entire system.

[0033] Example 2 This embodiment further adds an air volume adjustment component 13 and a linkage transmission mechanism 14 to the first embodiment to achieve coordinated adjustment of the angle of the return plate body 91 and the air volume, thereby further improving the stone removal effect.

[0034] The airflow regulating assembly 13 includes a damper plate 131 rotatably mounted inside the suction duct 4. The suction duct 4 has a round or square tube structure, and the shape of the damper plate 131 matches the cross-section of the inner cavity of the suction duct 4. Its second rotating shaft 1311 is horizontally inserted through the wall of the suction duct 4, and both ends of the second rotating shaft 1311 are supported by sealed bearings. One end of the second rotating shaft 1311 of the damper plate 131 extends outside the suction duct 4 and is fixedly connected to a second swing arm 143. When the second swing arm 143 swings, it drives the damper plate 131 to rotate, thereby changing the effective ventilation cross-sectional area of ​​the suction duct 4 and realizing continuous adjustment of the air intake volume.

[0035] like Figure 3 As shown, the linkage transmission mechanism 14 includes a first swing arm 141, a connecting rod 142, and a second swing arm 143. The first swing arm 141 is fixed to one end of the first rotating shaft 911 of the return plate body 91 that extends out of the side plate of the screen box 2. One end of the connecting rod 142 is hinged to the free end of the first swing arm 141, and the other end is hinged to the free end of the second swing arm 143.

[0036] When the return plate body 91 rotates, the first rotating shaft 911 drives the first swing arm 141 to swing, and the first swing arm 141 drives the second swing arm 143 to swing through the connecting rod 142, thereby driving the damper plate 131 to rotate synchronously. By reasonably setting the length ratio of the first swing arm 141 and the second swing arm 143 and the hinge point position of the connecting rod 142, a specific linkage relationship between the angle of the return plate body 91 and the opening of the damper plate 131 can be achieved. In this embodiment, the linkage relationship is configured as follows: when the return plate body 91 rotates in the direction of increasing the return amount, the damper plate 131 rotates in the direction of increasing the opening, thereby increasing the suction volume, enhancing the upward airflow, and assisting in blowing more light grains back to the screen surface; when the return plate body 91 rotates in the direction of decreasing the return amount, the damper plate 131 rotates in the direction of decreasing the opening, thereby decreasing the suction volume, weakening the upward airflow, and making it easier for heavier stones to be discharged from the stone discharge port 7. Through this mechanical linkage structure, the angle of the return plate and the air volume can be synchronously and adaptively adjusted without the need for additional sensors and actuators, simplifying the control system while ensuring the coordination between the two.

[0037] To adapt to the different requirements of destoning processes for different types of grains, this embodiment has multiple hinge holes 1411 spaced apart along the length of the first swing arm 141. The end of the connecting rod 142 can be selectively connected to any of the hinge holes 1411 via a pin. When the connecting rod 142 is connected to a hinge hole 1411 near the first rotating shaft 911, the effective swing arm of the first swing arm 141 is shorter, and the same angle change of the return plate body 91 only causes a small rotation angle of the damper plate 131, i.e., the transmission ratio is small; conversely, when the connecting rod 142 is connected to a hinge hole 1411 far from the first rotating shaft 911, the transmission ratio is larger. The operator can flexibly adjust the transmission ratio between the angle of the return plate and the air volume by changing the hinge position of the connecting rod 142 according to the material characteristics, making the equipment more widely applicable. For example, for rice with a lower specific gravity, a smaller transmission ratio can be selected to avoid excessively drastic changes in air volume; for corn with a higher specific gravity, a larger transmission ratio can be selected to enhance the range of air volume adjustment.

[0038] Example 3 This embodiment provides a specific working process of the above-mentioned destoner to further illustrate the technical effects of the present invention.

[0039] After the equipment is started, the vibration mechanism 3 drives the screen box 2 to generate reciprocating vibration, and the fan provides upward airflow into the screen box 2 through the suction pipe 4. The grain to be processed enters the screen box 2 through the feed pipe 5 and falls onto the screen mesh 8. Under the combined action of vibration and airflow, the material is stratified according to its specific gravity: the less dense grains are suspended in the upper layer and flow along the screen surface to the discharge port 6; the more dense stones sink to the lower layer and move upward along the screen surface to the rear end of the screen mesh 8 and enter the area where the return plate body 91 is located.

[0040] Initially, the return plate body 91 is at a preset intermediate angle. Under the action of the return plate body 91, part of the mixed material is intercepted and returned to the screen 8, and part is discharged from the discharge port 7. The image acquisition module captures images of the material discharged from the discharge port 7 in real time, and the image analysis module analyzes and obtains the current loss rate (e.g., 8.2%). This value is within the preset threshold range (5%~15%), so the controller 11 does not issue adjustment commands, and the equipment operates stably.

[0041] When the stone content in the wheat feed suddenly increases, or when changes in material moisture alter the stratification characteristics, the proportion of grain discharged from the stone discharge port 7 may rise to 18%, exceeding the upper limit threshold of 15%. Upon receiving the loss rate signal, the controller 11 calculates the target angle using PID control and sends a positive pulse signal to the stepper motor, driving the return plate body 91 to rotate 2° in the direction of increasing the return material volume. Simultaneously, the angle sensor 12 provides real-time feedback of the actual angle, and the controller 11 performs closed-loop angle correction. Under the action of the linkage transmission mechanism 14, as the return plate body 91 rotates, the damper plate 131 is synchronously driven, moderately increasing the suction volume to assist in blowing more grain back to the screen surface. After approximately 3-5 seconds, the loss rate signal gradually decreases, and adjustment stops when it drops below 15%. If the loss rate continues to decrease to below 5%, the controller 11 will reverse the adjustment of the return plate body 91, appropriately reducing the return material volume to ensure effective stone removal.

[0042] Through the aforementioned adaptive adjustment process, the destoner can automatically maintain the optimal stone removal loss rate when raw material characteristics fluctuate, ensuring both stone removal rate and minimizing grain loss. Actual testing shows that using the destoner of this invention, the stone removal loss rate fluctuation range can be controlled within ±2%. Compared to traditional manual adjustment methods, grain loss is reduced by approximately 30% to 50%, significantly improving processing efficiency.

[0043] In summary, by introducing loss rate detection and closed-loop control, and combining the linkage adjustment of the 91-degree angle of the return plate body and the air volume, this invention realizes intelligent and automated control of the stone discharge process of the destoner, which significantly improves the destone removal effect and grain utilization rate.

[0044] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A destoner with closed-loop control function for stone loss rate, comprising a frame, a screen box inclinedly mounted on the frame, a vibration mechanism for driving the screen box to reciprocate, a suction pipe mounted on the top of the screen box, a feed pipe mounted on the top of the screen box and located behind the suction pipe, a discharge port mounted on the front side of the screen box, and a stone discharge port mounted on the rear side of the screen box, wherein the screen box is equipped with a screen mesh, characterized in that, Also includes: The return plate assembly is installed inside the screen box and located above the rear end of the screen, including a return plate body rotatably mounted on the side plate of the screen box and an electric actuator that drives the return plate body to rotate around a first rotating shaft. The detection unit, located at the stone discharge port, is used to detect the proportion of stones and grains in the material discharged from the stone discharge port in real time and generate a corresponding loss rate signal. The controller is electrically connected to the electric actuator and the detection unit respectively. The controller is configured to automatically send adjustment commands to the electric actuator to change the tilt angle of the return plate body based on the comparison result of the received loss rate signal and the preset threshold.

2. The destoner with closed-loop control function for stone loss rate according to claim 1, characterized in that, The detection unit includes: The image acquisition module is used to acquire images of the material being discharged from the stone discharge port in real time. The image analysis module, electrically connected to the image acquisition module, is used to analyze the acquired images, identify the pixel area ratio of stones and grains in the discharged material, and generate a loss rate signal based on the ratio.

3. The destoner with closed-loop control function for stone loss rate according to claim 2, characterized in that, The image analysis module has a built-in deep learning-based image recognition model for stones and grains. The recognition model is trained by multiple sets of sample images with pre-labeled stone and grain regions.

4. The destoner with closed-loop control function for stone loss rate according to claim 1, characterized in that, The controller is configured as follows: When the loss rate signal exceeds the preset upper limit threshold, a first adjustment command is sent to the electric actuator to drive the return plate body to rotate in the direction of increasing the amount of return material. When the loss rate signal is lower than the preset lower threshold, a second adjustment command is sent to the electric actuator to drive the return plate body to rotate in the direction of reducing the amount of return material.

5. The destoner with closed-loop control function for stone loss rate according to claim 4, characterized in that, An angle sensor is provided between the first rotating shaft and the side plate of the screen box. The angle sensor is electrically connected to the controller and is used to provide real-time feedback on the current angle position of the return plate body. The controller is configured to perform closed-loop control of the electric actuator based on the deviation between the current angle position and the target angle position.

6. The destoner with closed-loop control function for stone loss rate according to claim 1, characterized in that, The electric actuator is a stepper motor or a servo motor, and the output shaft of the stepper motor or servo motor is connected to the first rotating shaft of the return plate body.

7. The destoner with closed-loop control function for stone loss rate according to claim 1, characterized in that, Also includes: The airflow regulating assembly includes a damper plate that is rotatably mounted inside the air intake duct via a second rotating shaft.

8. The destoner with closed-loop control function for stone loss rate according to claim 7, characterized in that, Also includes: The linkage transmission mechanism is connected to the return plate body and the damper plate respectively. The linkage transmission mechanism is configured to drive the damper plate to rotate synchronously when the return plate body rotates around the first rotating shaft, so as to realize the synchronous adjustment of the tilt angle of the return plate body and the air intake volume of the suction pipe.

9. The destoner with closed-loop control function for stone loss rate according to claim 8, characterized in that, The linkage transmission mechanism includes: The first swing arm is fixedly connected to the end of the first rotating shaft of the return plate body; The second swing arm is fixedly connected to the end of the second rotating shaft of the damper plate; A connecting rod, one end of which is hinged to a first swing arm and the other end of which is hinged to a second swing arm; When the return plate body rotates, the first rotating shaft drives the first swing arm to swing, and the first swing arm drives the second swing arm to swing through the connecting rod, thereby driving the damper plate to rotate synchronously.

10. The destoner with closed-loop control function for stone loss rate according to claim 9, characterized in that, The first swing arm is provided with a plurality of hinge holes spaced apart along the length direction. The end of the connecting rod can be selectively connected to any of the hinge holes to adjust the transmission ratio between the return plate body and the damper plate.

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