Intelligent door anti-pinch method and system

Abstract

The invention relates to an intelligent door anti-pinch method and system, an intelligent door comprises a frame body and a movable leaf capable of being opened and closed in a sliding mode in the frame body, and the method comprises the steps that the rotation angle value of a motor shaft of a motor unit is collected in real time; measuring an actual distance value between a preset measuring point on the movable leaf and a corresponding reference surface on the door frame in real time through a distance sensor; calculating a theoretical displacement value of the movable fan relative to the initial zero point based on the rotation angle value; continuously comparing the deviation value between the theoretical displacement value and the actual distance value in the displacement process of the movable fan; when the deviation value exceeds a preset safety threshold value, it is judged that the foreign matter exists; and sending a control instruction for stopping door closing or reverse operation. According to the scheme, whether foreign matter blocking exists or not is effectively recognized by comparing the deviation between the motor rotation angle and the theoretical displacement and the deviation between the sensor distance measurement and the actual distance, and non-contact obstacle clamping judgment is achieved. And the method is suitable for various forms of intelligent sliding door systems.

Description

Technical Field

[0001] The present application relates to the field of doors and windows, and in particular to an intelligent door anti-pinch method and system. Background Art

[0002] With the development of smart buildings and smart homes, smart doors are widely used in residences, office buildings, shopping malls, and other places. Ensuring safety while improving user experience has become a key direction for the evolution of smart door technology. The anti-pinch function, as a key link in ensuring user safety, is particularly important.

[0003] Common smart door anti-pinch solutions currently available include placing infrared or ultrasonic sensors on both sides of the door or in the doorframe. These sensors detect whether an object enters a pre-defined area during the door's opening and closing process, thereby determining whether there is a risk of entrapment. However, this approach presents the following challenges: the detection range is limited by the installation angle and door structure, resulting in blind spots; the ability to detect small, low-reflectivity, or fast-moving objects is limited; and environmental interference (such as strong light, moisture, and dust) can easily affect distance measurement accuracy. Alternatively, the current fluctuations during door operation are used as a basis for detection. When an obstacle increases resistance, the current surges, triggering the anti-pinch action. However, this approach suffers from response delays, and current anomalies must be detected only after the door has made contact with a foreign object. Furthermore, these solutions are susceptible to interference from factors such as voltage fluctuations and load variations, leading to false or missed detections. Alternatively, mechanisms such as elastic contact edges and micro switches are installed on the door's edges. Once the door contacts an obstacle and presses the switch, the anti-pinch action is triggered. However, these approaches are mechanical contact solutions, essentially detecting after entrapment has occurred, and are less effective in preventing injuries.

[0004] In summary, existing anti-pinch technologies generally have the following shortcomings: most rely on a "post-contact response" mechanism and cannot achieve "predictive anti-pinch"; they rely on a single sensing method and are easily affected by environmental noise, structural differences, etc.; the action response mechanism is rigid: it is unable to make differentiated treatments for different types of pinching situations (software / hardware / continuous obstacles); it is impossible to maintain the consistency of sensor data with the actual operation trajectory of the door body for a long time, and the system is prone to cumulative errors.

[0005] Therefore, there is an urgent need for a dual data fusion mechanism that integrates motor displacement estimation and distance sensor detection, which can not only judge the door movement status in real time, but also predict in advance whether there is any obstacle pinching behavior, thereby achieving a safer, more reliable and intelligent anti-pinch control strategy. Summary of the Invention

[0006] The purpose of this application is to solve the problems that the above-mentioned anti-pinch system cannot achieve early prediction, has limited detection accuracy, and has weak calibration capabilities.

[0007] According to one aspect of the present application, a method for preventing pinching of an intelligent door is provided. The intelligent door includes a frame and a movable door that can be slid open or closed within the frame. The method includes:

[0008] Real-time acquisition of a rotation angle value of a motor shaft of a motor unit, wherein the motor unit is mechanically connected to the movable fan and converts the rotational motion of the motor shaft into a linear displacement of the movable fan through a transmission mechanism;

[0009] The actual distance between the preset measuring point on the movable door sash and the corresponding reference surface on the door frame is measured in real time by the distance sensor;

[0010] Calculating a theoretical displacement value of the movable fan relative to an initial zero point based on the rotation angle value;

[0011] During the displacement of the movable sector, continuously comparing the deviation value between the theoretical displacement value and the actual distance value;

[0012] When the deviation value exceeds a preset safety threshold, it is determined that a foreign object exists;

[0013] Send control instructions to stop door closing and / or reverse operation.

[0014] Preferably, the method further comprises a calibration step, specifically comprising:

[0015] When the movable fan moves to the fully closed position, a calibration signal is triggered by contact between the reed switch and the calibration magnet;

[0016] Resetting the theoretical displacement value at that moment to zero;

[0017] The measurement value of the distance sensor at this moment is set as the initial reference value.

[0018] Preferably, after determining that a foreign object exists, the method further includes:

[0019] Continue to track the changing trend of the deviation value;

[0020] If the deviation value continues to increase, an enhanced reversing operation is performed, including increasing the motor reversing speed and extending the reversing stroke to quickly release the clamped object.

[0021] Preferably, the distance sensor is a laser ranging or infrared ranging element with a ranging range of 5 cm to 100 cm and a ranging accuracy of not less than ±1 cm;

[0022] The rotation angle value of the motor shaft of the motor unit is collected by a rotary encoder, and the resolution of the rotary encoder is not less than 360 pulses / revolution, which is used to achieve high-precision matching judgment between theoretical displacement and actual distance.

[0023] Preferably, the method further comprises:

[0024] During the operation of the door, the rotation angle value and the actual distance value are recorded periodically.

[0025] When an error is detected three times in a row, an alarm signal is issued to remind the user to manually perform a calibration operation, using the rotation value and distance value at the current door closing end point as the new reference zero point.

[0026] The present invention further provides an intelligent door anti-pinch system, which applies any of the intelligent door anti-pinch methods described above, comprising:

[0027] a motor unit mechanically connected to the movable fan, converting the rotational motion of the motor shaft into linear displacement of the movable fan through a specific transmission mechanism; under the control of the control module, the motor unit drives the movable fan along the guide track at a preset speed by controlling the forward or reverse rotation of the motor body; the motor unit includes a rotary encoder integrated into the motor body for detecting the rotation angle or number of revolutions of the motor shaft;

[0028] a distance sensor, mounted on the door frame and / or the movable leaf, for detecting in real time the actual distance between a preset measuring point on the movable leaf and a preset reference point on the door frame;

[0029] The control module is communicatively connected to the motor unit and the distance sensor, and is used to:

[0030] Based on the data collected by the rotary encoder and the preset transmission parameters, the theoretical displacement value of the movable fan relative to the initial position is calculated;

[0031] Get the actual distance value measured by the distance sensor in real time;

[0032] Comparing the deviation between the theoretical displacement value and the actual distance value during the door closing process;

[0033] When the deviation value exceeds a set safety threshold, it is determined that a foreign object exists, and an instruction to stop closing the door or reverse operation is sent to the motor unit.

[0034] Preferably, the distance sensor comprises any one of the following micro sensors:

[0035] A laser distance measuring sensor is installed on the side of the door frame, and its emission light path is parallel to the movement trajectory of the movable door;

[0036] Ultrasonic sensor, embedded in the bottom of the movable fan;

[0037] Hall effect sensors are used in conjunction with a magnetic grid array placed on the door frame.

[0038] Preferably, a zero point calibration module is provided at the position where the movable fan is in a fully closed position, comprising:

[0039] Magnetic reed switch, installed in the sealing groove of the door frame;

[0040] A calibration magnet is set at a position corresponding to the movable fan;

[0041] The control module responds to the reed switch trigger signal and sets the current rotation angle value and distance value as the theoretical displacement zero point and distance zero point respectively.

[0042] Preferably, the control module is connected to a human-computer interaction interface arranged on a door frame or a wall, and the interface includes a buzzer and an LED indicator light. When the system detects a foreign object obstacle, the control module controls the buzzer and the LED indicator light to send out an alarm signal.

[0043] Preferably, the control module includes a reset trigger unit, and the user can trigger the system to enter the zero-point calibration mode through a physical button, with the rotation angle value and the actual distance value in the current fully closed state of the door body as new reference values.

[0044] The present application has the following beneficial effects: by comparing the deviation between "motor rotation angle → theoretical displacement" and "sensor distance → actual distance", it can effectively identify whether there is a foreign object blocking it and realize non-contact obstacle judgment. The rotary encoder works in conjunction with the high-precision distance sensor to ensure that the data comparison results are accurate, and it is suitable for low-speed or high-speed door scenarios. The system can not only stop closing the door immediately, but also judge the continued existence of the obstacle based on the deviation trend and perform a reverse release action, effectively avoiding secondary pinching. The consistency of the displacement-distance judgment is guaranteed through calibration mechanisms such as reed switches or button operations, and high accuracy can be maintained during long-term operation. It does not rely on a specific type of sensing device or external equipment, and is suitable for various forms of intelligent sliding door systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the implementation methods of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the implementation methods or the description of the prior art. Obviously, the drawings described below are only some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0046] Figure 1 This is a logic block diagram of an intelligent door anti-pinch method described in one embodiment of the present application. DETAILED DESCRIPTION

[0047] To facilitate understanding of the present application, a more comprehensive description of the present application will be provided below with reference to the accompanying drawings. The accompanying drawings illustrate preferred embodiments of the present application. However, the present application may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure of the present application.

[0048] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are intended only to describe specific embodiments and are not intended to limit this application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0049] Please refer to Figure 1 An embodiment of the present application provides a method for preventing pinching of a smart door. The smart door includes a frame and a movable door that can be slid open or closed within the frame. The method includes:

[0050] S10. Real-time acquisition of the rotation angle value of the motor shaft of the motor unit. The motor unit is mechanically connected to the movable door and converts the rotational motion of the motor shaft into linear displacement of the movable door via a transmission mechanism. Because the push-pull motion of the movable door is driven by the motor unit, the rotary encoder, as a detection device directly coupled to the motor shaft, can output the rotation angle or number of revolutions in real time with high precision. After conversion of the transmission parameters, this angle value corresponds to the theoretical displacement of the door body. Therefore, this step provides accurate basic data for the subsequent construction of the "theoretical displacement curve."

[0051] S20. Use a distance sensor to measure the actual distance between a preset measuring point on the movable door sash and a corresponding reference surface on the door frame in real time. Using a distance sensor to measure the actual distance between a preset measuring point on the movable door sash and a corresponding reference surface on the door frame is a key method for constructing the "actual distance curve" in the present invention. This distance value can reflect the actual opening gap between the door body and the door frame at any given moment and is an important basis for determining whether there are obstructions or obstacles. Compared to traditional limit switches or infrared detection, distance sensors have advantages in accuracy and response speed and are particularly suitable for high-speed or medium-speed doors.

[0052] S30. Calculate the theoretical displacement of the movable sash relative to the initial zero point based on the rotation angle. The angle output by the rotary encoder is combined with the preset motor-door transmission parameters to convert it into the theoretical displacement of the movable sash relative to the initial position. This conversion allows for accurate reproduction of the door's motion trajectory. This method, particularly when the transmission system utilizes a screw, sprocket, or rack structure, can establish a one-to-one mapping relationship between the rotation angle and displacement, further enhancing the control system's predictive capabilities and judgment accuracy.

[0053] S40: During the movement of the movable door, the deviation between the theoretical displacement value and the actual distance value is continuously compared. This enables real-time comparison between the theoretical trajectory and the actual distance measurement during the door's movement. By continuously collecting and comparing theoretical displacement values ​​with actual distance values, the system establishes a continuous dynamic error monitoring mechanism throughout the door's movement. Compared to solutions that only detect obstacles at the end point, this step provides an early warning at the initial stage of the obstacle formation, significantly improving the timeliness and safety of the anti-pinch response.

[0054] S50: When the deviation exceeds the preset safety threshold, a foreign object is detected. A reasonable deviation threshold is set. Once the comparison result exceeds this threshold, an obstacle is detected during door operation. This judgment method does not rely on the material, conductivity, or reflective properties of the obstacle, but instead relies on a "theory-to-practice" logical error analysis, resulting in greater versatility and adaptability. It is particularly effective in identifying soft obstructions (such as towels and fingers).

[0055] S60: Send a control command to stop closing the door and / or reverse operation. If a foreign object is detected, the control system immediately sends a stop or reverse operation command to the motor unit. The control strategy can be further optimized based on the deviation trend. For minor deviations, a deceleration and stop strategy can be implemented. For severe deviations or those that continue to increase, a high-speed reverse release action can be initiated, effectively preventing pinching and ensuring the safety of people and objects.

[0056] By implementing the technical solution of this embodiment, by comparing the deviation between "motor rotation angle → theoretical displacement" and "sensor distance → actual distance", it is possible to effectively identify whether there is a foreign object blocking the way and realize non-contact obstacle judgment. The rotary encoder works in conjunction with the high-precision distance sensor to ensure accurate data comparison results, which is suitable for low-speed or high-speed door scenarios. The system can not only stop closing the door immediately, but also judge the continued existence of the obstacle based on the deviation trend and perform a reverse release action, effectively avoiding secondary pinching. The consistency of the displacement-distance judgment is guaranteed through calibration mechanisms such as reed switches or button operations, and high accuracy can be maintained during long-term operation. It does not rely on a specific type of sensing device or external equipment and is suitable for various forms of intelligent sliding door systems.

[0057] In a specific embodiment, a calibration step is further included before S10, specifically including:

[0058] S11. When the movable door moves to the fully closed position, the calibration signal is triggered by the contact between the reed switch and the calibration magnet. It is used to realize automatic recognition and triggering of the zero position of the system. When the movable door moves to the fully closed position, the reed switch provided in the sealing groove of the door frame contacts the calibration magnet installed on the movable door in precise alignment, and then outputs a calibration signal. This signal can be recognized by the control module in real time as a trigger condition for the synchronous calibration of the system displacement and distance measurement. Compared with traditional mechanical limit or manual operation methods, this step provides a non-contact, highly reliable closed state confirmation mechanism, which provides a trigger basis for subsequent data reset.

[0059] S12. Reset the theoretical displacement value at that moment to zero. After receiving the calibration signal, the theoretical displacement value currently output by the rotary encoder is reset to zero, using the current motor shaft rotation angle as the "starting point." Because the displacement value output by the rotary encoder has a cumulative nature, if it is not calibrated over a long period of operation, cumulative drift may occur due to mechanical slip, gear backlash, or transmission error. Therefore, this reset operation effectively avoids the problem of theoretical displacement distortion caused by long-term operation, ensuring that each door closing process starts from a unified zero position, maintaining the consistency of calculation accuracy within the system.

[0060] S13. Set the distance sensor's measured value at that moment as the initial reference value. The actual value measured by the distance sensor at that moment is set as the initial reference value, meaning that the distance between the door and the door frame at that moment is considered to be the standard "closing distance." This setting facilitates accurate deviation calculations in subsequent judgments. In particular, the actual closing gap may vary slightly depending on the door structure (e.g., glass door, metal door, composite door) or installation tolerances. This reference value enables the system to have adaptive judgment capabilities in different scenarios, improving environmental adaptability and stability.

[0061] Implementing the technical solution of this embodiment can achieve the following beneficial effects:

[0062] The introduction of a reed switch and magnetic trigger mechanism enables accurate and reliable closed-door zero-point calibration, effectively preventing false triggering and environmental interference. Synchronously resetting the reference values ​​of the rotary encoder and distance sensor enables bidirectional, unified calibration of the motion trajectory and distance measurement benchmark, enhancing system data consistency. This improves the drift resistance and stability of the entire anti-pinch system during long-term operation, preventing anti-pinch failure due to error accumulation. Automatic calibration capabilities reduce reliance on manual intervention, enhancing system intelligence and user convenience. Improved adaptability and judgment accuracy in various installation environments provide a more solid technical foundation for subsequent deviation judgment and anti-pinch strategy execution.

[0063] In an optional embodiment, after determining that a foreign object exists in S50, the method further includes:

[0064] S51. Continue to track the changing trend of the deviation value. This step introduces a dynamic trend tracking mechanism for the deviation value. That is, after initially determining the presence of a foreign object, the system does not immediately enter a fixed action process. Instead, it continuously collects the deviation value between the theoretical displacement and the actual distance and establishes its changing trend curve. By determining whether the deviation value continues to expand, slowly decreases, or remains stable within a short period of time, the type and thickness of the obstacle can be further inferred, as well as whether the pressure is continuously applied. Unlike the traditional "one-time threshold trigger" mechanism, this step improves the system's adaptability to complex obstacle situations through a dynamic judgment mechanism, helping to avoid misjudgments and optimize the strength and form of subsequent reaction actions.

[0065] S52. If the deviation value continues to increase, an enhanced reversal operation is performed, including increasing the motor reversal speed and extending the reversal stroke to quickly release the clamped object. According to the above trend analysis results, if it is judged that the deviation value continues to increase, it means that the obstacle has not been released and may even be further oppressed. At this time, the system performs an enhanced reversal operation. Different from the ordinary reversal strategy, the motor reversal speed is appropriately increased during the reversal action, and the reversal stroke is extended to quickly pull the door back with greater force to ensure that the clamped objects (such as fingers, cloth, children's toys, etc.) can be released in time. This enhanced reversal action not only improves the efficiency of obstacle release, but also reduces the risk of injury caused by excessive clamping time. It is a more humane and safe supplementary control strategy.

[0066] Implementing the technical solution of this embodiment adds a trend judgment link after foreign object identification, improves the system's ability to identify the persistence and severity of entrapment, and enhances the accuracy of intelligent judgment. By triggering with dynamic trend changes rather than static thresholds, false triggering or false reversal caused by occasional signal fluctuations or small structural interference is avoided. Execute enhanced reversal actions to provide stronger release force and longer recovery distance in necessary scenarios, effectively preventing high-risk events such as entanglement of soft objects and children being pinched. Provide graded response strategies for entrapment situations of different complexities to improve the system's scene adaptability and practicality. Enhance the system's safety performance and user trust, and it is particularly suitable for use in homes, nursing homes, kindergartens, and other environments with high safety protection requirements.

[0067] In a specific embodiment, the distance sensor is a laser ranging or infrared ranging element with a ranging range of 5 cm to 100 cm, a ranging accuracy of not less than ±1 cm, and a resolution of the rotary encoder of not less than 360 pulses / revolution, which is used to achieve high-precision matching judgment between theoretical displacement and actual distance.

[0068] In this embodiment, it should be noted that the distance sensor used is a laser ranging element or an infrared ranging element, and its ranging range is set to 5cm to 100cm, covering the active distance of most common smart sliding doors during the opening and closing process. The ranging accuracy is not less than ±1cm, which means that when the system dynamically monitors the distance between the door leaf and the door frame, it can output relatively stable, continuous and high-confidence actual distance data in real time, effectively reducing the error interference caused by signal jitter. Especially in anti-pinch detection, even if the thickness of the foreign object is small (such as fingers, clothing edges, etc.), the deviation can be identified within the tolerance range of the ranging error.

[0069] At the same time, the resolution of the rotary encoder used in this embodiment is no less than 360 pulses per revolution, that is, it can output at least 360 position points per rotation. After linear displacement conversion is performed on the door's transmission structure (such as the lead screw, rack, and synchronous belt), the rotation angle of the motor shaft can be mapped to the door's linear displacement trajectory with high precision. This resolution is sufficient to support centimeter-level or even sub-centimeter-level displacement conversion in current smart door scenarios, ensuring that the theoretical displacement values ​​calculated by the system have high accuracy and consistency.

[0070] The control module synchronously collects data from the distance sensor and rotary encoder, establishing a "theoretical displacement - actual distance" correspondence to form a highly accurate anti-pinch deviation judgment mechanism. Even at high door speeds, millisecond-level response is achieved, enabling real-time error identification and dynamic protective response.

[0071] Implementing the technical solution of this embodiment can achieve the following technical effects:

[0072] Laser or infrared ranging devices provide high-precision distance monitoring capabilities, capable of identifying subtle obstacles and improving the sensitivity of anti-pinch detection. A high-resolution rotary encoder enables continuous and precise displacement tracking during door movement, providing stable support for theoretical displacement calculations. The fusion of distance and displacement signals gives the anti-pinch system advantages such as low error tolerance, fast response, and strong environmental adaptability. This significantly improves the accuracy and reliability of intelligent door anti-pinch systems, meeting the needs of high-security locations such as residences, hospitals, and public buildings.

[0073] In a specific embodiment, the method further comprises:

[0074] S70. During the operation of the door, the rotation angle value and the actual distance value are periodically recorded. By periodically recording the rotation angle value and the actual distance value during the operation of the door, a basic support is provided for the system to establish historical displacement-distance relationship data. This recording can be performed at preset time intervals, displacement increments, or trigger events to generate a comparison table of theoretical displacement and actual distance under multiple typical conditions during the door opening and closing process. This mechanism not only facilitates subsequent deviation analysis of the system, but also provides a traceable data basis for judging potential problems such as transmission wear and displacement drift. Compared with real-time judgment, periodic recording emphasizes the monitoring of the accumulation of trend errors and plays an important role in improving the long-term stability of the system.

[0075] S80. When an error is determined three times in a row, an alarm signal is issued to remind the user to manually perform a calibration operation, with the rotation value and distance value at the current door closing end point as the new reference zero point. An alarm and user guidance mechanism is set that is triggered after multiple error determinations. When the system detects a repetitive or persistent deviation between the theoretical displacement and the actual distance in multiple operating cycles, it indicates that the current zero point reference value may have drifted. At this time, the control module can issue an alarm signal through a buzzer, LED indicator, touch screen prompt, etc., prompting the user to enter the calibration mode. The user can confirm the calibration when the door is fully closed, and the system will set the rotary encoder value and distance value at that moment as the new theoretical zero point and distance measurement reference value respectively. This method combines the system's self-judgment capability with the user's active participation mechanism, effectively making up for the boundary condition limitations of the automatic calibration mechanism.

[0076] By implementing the technical solution of this embodiment, an error trend tracking mechanism is established during the operation of the door body through periodic data recording, thereby improving the system's ability to identify chronic offset problems. Alarms are issued based on multiple historical error judgments to avoid false triggering of calibration due to occasional errors, thereby ensuring the stability and robustness of the system's judgments. The introduction of user manual calibration operations gives the system flexible self-recovery capabilities, allowing it to maintain a good operating state in extreme scenarios (such as strong external force interference and hardware aging). Visual alarms and operation feedback are provided to enhance the maintainability and user-friendliness of the system and reduce maintenance costs. The system is supported to maintain high-precision displacement-distance mapping matching capabilities after long-term operation, further improving the reliability and sustainability of the anti-pinch function.

[0077] In a specific embodiment, the present invention further provides an intelligent door anti-pinch system, applying any of the above intelligent door anti-pinch methods, comprising:

[0078] The motor unit is mechanically connected to the movable fan and converts the rotational motion of the motor shaft into linear displacement of the movable fan through a specific transmission mechanism. Under the control of the control module, the motor unit drives the movable fan along the guide track at a preset speed by controlling the forward or reverse rotation of the motor body. The motor unit includes a rotary encoder integrated into the motor body for detecting the rotation angle or number of revolutions of the motor shaft.

[0079] A distance sensor is installed on the door frame and / or the movable leaf, and is used to detect in real time the actual distance between a preset measuring point on the movable leaf and a preset reference point on the door frame;

[0080] The control module is connected to the motor unit and the distance sensor for:

[0081] Based on the data collected by the rotary encoder and the preset transmission parameters, the theoretical displacement value of the movable fan relative to the initial position is calculated;

[0082] Get the actual distance value measured by the distance sensor in real time;

[0083] Compare the deviation between the theoretical displacement value and the actual distance value during the door closing process;

[0084] When the deviation value exceeds the set safety threshold, it is determined that there is a foreign object and an instruction to stop closing the door or reverse operation is sent to the motor unit.

[0085] In this embodiment, it should be noted that the intelligent door anti-pinch system is built on a motor control architecture directly coupled to the movable fan. The core components of the system include a motor unit, a distance sensor and a control module, and the closed-loop response of the door anti-pinch control is achieved through the collaboration of software and hardware.

[0086] Among them, the motor unit is mechanically connected to the movable fan through a preset transmission mechanism (such as a gear set, pulley, chain, screw, etc.) to drive the door body to perform linear push-pull motion along the guide track. Under the control of the control module, the motor can run forward or reverse and achieve smooth opening and closing at a set speed. At the same time, the motor unit is integrated with a rotary encoder for real-time acquisition of the rotation angle or number of turns of the motor shaft. It is a key component for constructing the theoretical displacement value. The angle data output by the encoder will be converted with the transmission ratio parameter within the system to correspond to the linear displacement path of the door body.

[0087] Distance sensors are installed on the door frame or movable sash. By setting the relative position of the measurement point to a reference surface, they dynamically measure the actual distance between the door and the door during opening and closing. Sensors can be laser, infrared, or ultrasonic distance measuring devices, ensuring stable detection across a variety of door structures and materials.

[0088] The control module, the brain of the system, communicates with the motor unit and the distance sensor. Its functions include:

[0089] According to the output value of the rotary encoder and the transmission parameters, the theoretical displacement value of the movable fan is calculated in real time;

[0090] Synchronously read the actual measurement data of the distance sensor;

[0091] During the operation of the door, the difference between the theoretical displacement and the actual distance is continuously compared and the deviation value is calculated;

[0092] Once the deviation value exceeds the set threshold, it is determined that there is a foreign object (such as human hands, debris, etc.) between the door body and the door frame;

[0093] The system immediately issues a stop or reverse operation command to the motor unit, interrupting the door closing action to avoid jamming.

[0094] The entire system forms a control structure of data closed loop + logic closed loop + action closed loop, ensuring that the anti-pinch action is not only real-time but also accurate.

[0095] By implementing the technical solution of this embodiment, a high-precision anti-pinch system based on the fusion of the motor rotation displacement and the actual distance measurement dual signal is constructed, which significantly improves the accuracy of misjudgment identification. The system can dynamically monitor deviations throughout the door movement, breaking the limitation of traditional limiters that only judge at the end point, and has full-process protection capabilities. The control module has the ability to make real-time judgments and issue instructions, achieving a millisecond-level response speed, and effectively preventing pinching incidents. The communication logic between modules is clear and the interface is standardized, which facilitates system maintenance and modular integration and has good industrial feasibility. It supports a variety of door structure application scenarios, such as sliding doors, track doors, automatic sliding doors, etc., and has strong versatility and market adaptability. The high-precision encoders and ranging sensors used improve the overall stability of the system and can be used in places with extremely high safety requirements, such as residences, hospitals, schools, and rail transit stations.

[0096] In a specific embodiment, the distance sensor includes any one of the following micro sensors:

[0097] The laser distance sensor is installed on the side of the door frame, and its emission light path is parallel to the movement trajectory of the movable door leaf;

[0098] Ultrasonic sensor, embedded in the bottom of the movable fan;

[0099] Hall effect sensors are used in conjunction with a magnetic grid array placed on the door frame.

[0100] In this embodiment, it should be noted that the distance sensor may be any of the following micro-distance measuring elements. The specific selection and installation method may be flexibly configured according to different door structures and application scenarios to achieve accurate monitoring of the actual distance between the movable leaf and the door frame:

[0101] Laser ranging sensors: These sensors are mounted on the side of the door frame. Their beam travels parallel to the direction of motion of the sash, aiming at a reflective area or specific measurement point on the sash. This installation method is suitable for linear motion structures such as track-sliding and sliding doors. Laser ranging offers non-contact, high accuracy, and fast response, making it particularly well-suited for applications requiring fast response times to obstacle detection.

[0102] Ultrasonic sensor: Embedded in the base of the movable door sash, it transmits ultrasonic pulses toward the door frame and receives the reflected echo to calculate the current distance. Ultrasonic ranging has the advantages of low reflective surface material requirements and strong adaptability. It is particularly suitable for working in dusty, poorly illuminated, or reflective environments. It also adapts well to irregular or curved reflective surfaces.

[0103] Hall Effect Sensor: This sensor is installed on the movable door sash and works in conjunction with a magnetic grid array mounted on the door frame. As the door moves, the Hall Effect sensor detects the number of magnetic poles it passes through, indirectly calculating displacement or relative position. This structure offers a compact design, stable response, and strong anti-interference capabilities, making it particularly suitable for smart door designs where space is limited or concealed installation is required.

[0104] The above three sensors can be selected as needed or used in combination to form a multi-redundant, multi-source verification mechanism to further improve ranging accuracy and system stability.

[0105] The implementation of the technical solution of this embodiment can achieve the following technical effects: providing a variety of micro-sensor configuration options to meet the installation requirements of different types of smart door structures, with a high degree of flexible adaptability. Supporting a variety of ranging principles (optical, acoustic, magnetic field) to ensure stable and reliable ranging under different environmental conditions. Suitable sensors can be selected according to accuracy requirements and spatial layout to improve the overall deployment convenience and maintainability of the system. The combined use of different types of sensors can build a multiple cross-validation mechanism to effectively reduce the risk of misjudgment caused by the failure of a single sensor. In environments with high requirements for safety and stability, such as homes, hospitals, and rail transit, the system's anti-pinch detection reliability and long-term operation stability are improved. Provide an expandable sensor data foundation for subsequent expansions such as environmental perception, self-learning calibration and other functions.

[0106] In a specific embodiment, a zero point calibration module is provided when the movable fan is in a fully closed position, comprising:

[0107] Magnetic reed switch, installed in the sealing groove of the door frame;

[0108] A calibration magnet is set at a position corresponding to the movable fan;

[0109] The control module responds to the reed switch trigger signal and sets the current rotation angle value and distance value as the theoretical displacement zero point and distance zero point respectively.

[0110] In this embodiment, it should be noted that a zero-point calibration module is provided when the movable fan is in the fully closed position, for achieving automatic baseline reset of the system displacement and distance measurement. This module mainly includes the following two hardware components and corresponding control response logic:

[0111] A reed switch, installed in the sealing groove of the door frame, serves as a fixed-end sensor element. When the door is fully closed, it uses magnetic field sensing to detect whether the movable leaf has reached its final position. This switch features a simple structure and high sensitivity, enabling highly reliable detection of the closed state without mechanical contact.

[0112] A calibration magnet, mounted on the movable leaf, is precisely aligned with the reed switch. When the leaf is fully closed, the magnet approaches and activates the reed switch, triggering a clear closure signal. This signal is recognized by the control module as a "physical endpoint reached," initiating the system calibration process.

[0113] Upon receiving the trigger signal from the reed switch, the control module immediately resets the rotation angle recorded by the rotary encoder to the theoretical zero point of displacement and sets the current measurement value collected by the distance sensor as the reference zero point of actual distance. This completes the global synchronous calibration of the "displacement-distance" judgment model at the system level.

[0114] The zero-point calibration module is automatically executed each time the door is fully closed, and can also be used in conjunction with manual user-triggered calibration mode, providing a stable and reliable reference for the entire anti-pinch system.

[0115] Implementing the technical solution of this embodiment can achieve the following technical effects:

[0116] By setting a reed switch and a magnetic alignment device at the physical closing end point of the door body, a contactless, low-power, and long-term stable zero-point identification method is achieved. The system automatically resets the current values ​​of the rotary encoder and the distance sensor each time it closes, constructing a unified reference coordinate system to ensure consistency between theoretical and actual value judgments. This avoids cumulative drift problems caused by transmission structure wear, installation errors, or long-term operation, and improves the system's anti-drift and self-recovery capabilities. The system's autonomous calibration capabilities are enhanced, eliminating the need for frequent manual intervention, improving the equipment's intelligence and ease of use. It ensures that anti-pinch judgments are based on the latest zero-point reference, making the identification of pinching objects more accurate, timely, and sensitive, and is especially suitable for high-frequency opening and closing scenarios. The structure is simple, low-cost, and easy to integrate, with good engineering feasibility and product application prospects.

[0117] In a specific embodiment, the control module is connected to a human-computer interaction interface set on a door frame or wall, and the interface includes a buzzer and an LED indicator light. When the system detects a foreign object obstacle, the control module controls the buzzer and LED indicator light to send an alarm signal.

[0118] In this embodiment, it should be noted that the control module is connected to a human-machine interface mounted on the door frame or wall. This interface includes a buzzer and LED indicator light, providing intuitive alerts to the user when critical events occur. When the anti-pinch system detects a deviation exceeding a preset threshold during the door closing process and preliminarily determines the presence of an obstructing object, the control module immediately controls the buzzer to emit a continuous or intermittent beep and the LED indicator to emit a flashing red light or multi-segment status light signal, providing multi-modal, multi-angle information prompts.

[0119] The human-machine interface is installed in a location easily visible or accessible to users, such as above a doorframe, near a side wall, or in the indoor control panel area, ensuring that alarms are immediately noticed and responded to. Furthermore, the buzzer and LED status can also be used to provide system status feedback during other operating states (such as calibration completed, abnormal operation, and waiting for maintenance).

[0120] Implementing the technical solution of this embodiment can achieve the following technical effects:

[0121] A multi-channel alarm system combining visual and audible signals enhances the system's ability to alert users to abnormal conditions. This alert alerts users to entrapment risks even without directly observing door movement, improving operational safety. The LED and buzzer feature a simple layout and responsive response, adapting to diverse installation environments with excellent compatibility and scalability. This facilitates future expansion into more advanced interactive modes such as touchscreens and voice prompts, providing a solid foundation for future upgrades.

[0122] In a specific embodiment, the control module includes a reset trigger unit, and the user can trigger the system to enter the zero-point calibration mode through a physical button, using the rotation angle value and actual distance value when the door is currently in a fully closed state as new reference values.

[0123] In this embodiment, it should be noted that the control module also includes a reset trigger unit. The user can actively trigger the system to enter zero-point calibration mode by pressing a physical button located on the door frame or wall. This button is typically designed to prevent accidental touches, such as requiring a 3-second press and hold and requiring double confirmation to take effect, to avoid accidental operation.

[0124] When the user manually triggers calibration mode using this button, the system automatically uses the current rotary encoder angle as the theoretical displacement zero point when the door is fully closed, and simultaneously sets the current actual value of the distance sensor as the distance measurement reference zero point. This method is suitable for situations where the system has experienced accumulated errors after long-term operation, or when drastic environmental changes have prevented automatic calibration from effectively recognizing the system, requiring user intervention for a one-time "hard reset."

[0125] Implementing the technical solution of this embodiment can achieve the following technical effects:

[0126] This system provides users with convenient access to manually intervene in system baseline corrections, enhancing system controllability. It also enables rapid restoration of normal operation in critical scenarios (such as motor reinstallation, sensor replacement, or severe displacement offset). The intuitive, simple button operation makes it easy to understand and execute, enhancing the system's user-friendliness and ease of maintenance. This complements the automatic calibration mechanism, improving the system's overall fault tolerance and self-recovery capabilities, ensuring long-term, high-precision operation.

[0127] The above-described embodiments merely represent several embodiments of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A smart door anti-pinch method, characterized in that: The smart door includes a frame and a movable door that can be slid open or closed within the frame. The method includes: Real-time acquisition of a rotation angle value of a motor shaft of a motor unit, wherein the motor unit is mechanically connected to the movable fan and converts the rotational motion of the motor shaft into a linear displacement of the movable fan through a transmission mechanism; The actual distance between the preset measuring point on the movable door sash and the corresponding reference surface on the door frame is measured in real time by the distance sensor; Calculating a theoretical displacement value of the movable fan relative to an initial zero point based on the rotation angle value; During the displacement of the movable sector, continuously comparing the deviation value between the theoretical displacement value and the actual distance value; When the deviation value exceeds a preset safety threshold, it is determined that a foreign object exists; Send control instructions to stop door closing and / or reverse operation.

2. The intelligent door anti-pinch method according to claim 1, characterized in that: The method further comprises a calibration step, specifically comprising: When the movable fan moves to the fully closed position, a calibration signal is triggered by contact between the reed switch and the calibration magnet; Resetting the theoretical displacement value at that moment to zero; The measurement value of the distance sensor at this moment is set as the initial reference value.

3. The intelligent door anti-pinch method according to claim 1, characterized in that: After determining that a foreign object exists, the method further includes: Continue to track the changing trend of the deviation value; If the deviation value continues to increase, an enhanced reversing operation is performed, including increasing the motor reversing speed and extending the reversing stroke to quickly release the clamped object.

4. The intelligent door anti-pinch method according to claim 1, characterized in that: The distance sensor is a laser distance measuring element or an infrared distance measuring element, with a distance measuring range of 5cm to 100cm and a distance measuring accuracy of not less than ±1cm; The rotation angle value of the motor shaft of the motor unit is collected by a rotary encoder, and the resolution of the rotary encoder is not less than 360 pulses / revolution, which is used to achieve high-precision matching judgment between theoretical displacement and actual distance.

5. The intelligent door anti-pinch method according to claim 1, characterized in that: The method further comprises: During the operation of the door, the rotation angle value and the actual distance value are recorded periodically. When errors are detected three times in a row, an alarm signal is issued to remind the user to manually perform calibration operations, using the rotation value and distance value at the current door closing end point as the new reference zero point.

6. An intelligent door anti-pinch system, applying the intelligent door anti-pinch method according to any one of claims 1 to 5, characterized in that: include: a motor unit mechanically connected to the movable fan, converting the rotational motion of the motor shaft into linear displacement of the movable fan through a specific transmission mechanism; under the control of the control module, the motor unit drives the movable fan along the guide track at a preset speed by controlling the forward or reverse rotation of the motor body; the motor unit includes a rotary encoder integrated into the motor body for detecting the rotation angle or number of revolutions of the motor shaft; a distance sensor, mounted on the door frame and / or the movable leaf, for detecting in real time the actual distance between a preset measuring point on the movable leaf and a preset reference point on the door frame; The control module is communicatively connected to the motor unit and the distance sensor, and is used to: Based on the data collected by the rotary encoder and the preset transmission parameters, the theoretical displacement value of the movable fan relative to the initial position is calculated; Get the actual distance value measured by the distance sensor in real time; Comparing the deviation between the theoretical displacement value and the actual distance value during the door closing process; When the deviation value exceeds a set safety threshold, it is determined that a foreign object exists, and an instruction to stop closing the door or reverse operation is sent to the motor unit.

7. The intelligent door anti-pinch system according to claim 6, characterized in that: The distance sensor includes any of the following micro sensors: A laser distance measuring sensor is installed on the side of the door frame, and its emission light path is parallel to the movement trajectory of the movable door; Ultrasonic sensor, embedded in the bottom of the movable fan; Hall effect sensors are used in conjunction with a magnetic grid array placed on the door frame.

8. The intelligent door anti-pinch system according to claim 6, characterized in that: A zero point calibration module is provided when the movable fan is in a fully closed position, comprising: Magnetic reed switch, installed in the sealing groove of the door frame; A calibration magnet is set at a position corresponding to the movable fan; The control module responds to the reed switch trigger signal and sets the current rotation angle value and distance value as the theoretical displacement zero point and distance zero point respectively.

9. The intelligent door anti-pinch system according to claim 6, characterized in that: The control module is connected to a human-computer interaction interface set on a door frame or a wall. The interface includes a buzzer and an LED indicator light. When the system detects a foreign object obstacle, the control module controls the buzzer and the LED indicator light to send out an alarm signal.

10. The intelligent door anti-pinch system according to claim 6, characterized in that: The control module includes a reset trigger unit, and the user can trigger the system to enter the zero-point calibration mode through a physical button, using the rotation angle value and the actual distance value when the door is currently in a fully closed state as new reference values.

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