Anti-pinch and anti-collision protection system adaptive to table frame structure form and detection method

Abstract

The invention relates to the technical field of intelligent lifting tables, in particular to an anti-pinch and anti-collision protection system with a self-adaptive table frame structure form and a detection method.The self-adaptive table frame comprises table legs, a base, a table plate, a control box, a hand controller, a motor, a Hall sensor, a gyroscope and an anti-pinch and anti-collision module; according to the detection method of the anti-pinch and anti-collision protection system, anti-pinch and anti-collision are achieved through at least one of the following modes: detection of the gyroscope detection module, detection of the motor current detection module and detection of the Hall sensor detection module, the integrated anti-pinch and anti-collision system is constructed, each item can be independently deprotected, and the detection efficiency is improved. Even if any protection measure fails, the system can be continuously protected, so that the problem of non-uniform sensitivity caused by transmission structure difference is fundamentally solved; the anti-pinch device can be suitable for different steel frame structures to adapt to the transmission resistance and different loads, and the anti-pinch function is triggered more sensitively; and the cost of adding various sensors such as a pressure sensor in the lifting table is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent lifting tables, and in particular to an anti-pinch and anti-collision protection system and a detection method in the form of an adaptive table frame structure. Background Art

[0002] In today's society, thanks to the continuous advancement of the times and the rapid development of science and technology, motor transmission technology has been widely used, and its influence has penetrated into many fields, not only greatly reducing the intensity of human labor, but also bringing many conveniences to daily life. Among them, the intelligent lifting system, as a typical representative, has gradually become a common facility in people's lives, especially the lifting desk, which is deeply favored by office workers and greatly improves office comfort and work efficiency.

[0003] However, while electric products bring convenience, they also cause a series of safety issues that cannot be ignored. Due to the characteristics of motor drive, there is a potential risk of pinching or hitting the user during operation, making safety protection a key consideration in the development and production of electric products.

[0004] In the current market, there are endless safety protection measures for electric products, which are designed to deal with various potential dangerous situations. However, many existing protection solutions are often not suitable for special steel frame structures. On the one hand, some protection measures are too focused on adaptability to specific steel frames and excessively adjust parameters, resulting in abnormally high sensitivity of anti-pinch and anti-collision functions, and frequent false triggering, which not only interferes with normal use, but may also reduce the overall stability of the equipment; on the other hand, some protection measures have not been accurately adjusted, resulting in serious lack of sensitivity, and cannot respond in time when facing actual dangers, and cannot effectively protect the safety of users, and it is difficult to meet diverse actual needs.

[0005] In view of this, there is an urgent need for a new anti-pinch and anti-collision system that can effectively take into account different transmission structures to fill the gaps in existing technologies and ensure that electric products not only have efficient and practical functions, but can also provide users with reliable, stable and consistent safety protection. Summary of the invention

[0006] In order to solve the problems existing in the prior art, the present invention provides an anti-pinch and anti-collision protection system and detection method in the form of an adaptive desk frame structure, which is used to solve the current situation that the anti-pinch and anti-collision sensitivity of existing lowering office desks is too sensitive or insensitive due to the adaptation of special steel frame structures, and it is difficult to meet the requirements of different transmission structures.

[0007] To solve the above problems, the technical solution of the present invention is as follows: an anti-pinch and anti-collision protection system in the form of an adaptive table frame structure, the adaptive table frame includes two liftable table legs, a base is provided at the lower end of the table legs, a table board is provided at the upper end, a control box is provided on the lower end surface of the table board, and also includes a hand controller, the table legs are connected to a motor, a Hall sensor is provided in the motor, a gyroscope is provided in the control box, and an anti-pinch and anti-collision module is also provided in the control box, the anti-pinch and anti-collision module is electrically connected to the motor, the Hall sensor and the gyroscope, and the anti-pinch and anti-collision module can control the motor to brake or reverse according to the status of the motor, the Hall sensor and the gyroscope.

[0008] Furthermore, the anti-pinch and anti-collision module includes a gyroscope detection module, a motor current detection module, and a Hall sensor detection module.

[0009] Furthermore, the gyroscope detection module is electrically connected to the gyroscope and determines the collision based on the acceleration, tilt angle or vibration data of the gyroscope.

[0010] Furthermore, the motor current detection module is electrically connected to the motor and identifies resistance by analyzing motor current changes through a filtering algorithm.

[0011] Furthermore, the Hall sensor detection module is electrically connected to the Hall sensor and determines the obstacle according to the continuous abnormality of the Hall sensor pulse width time.

[0012] The detection method of the anti-pinch and anti-collision protection system is adopted, and the detection method realizes anti-pinch and anti-collision in at least one of the following ways: 1. Gyroscope detection module detection; 2. Motor current detection module detection; 3. Hall sensor detection module detection.

[0013] Further, the gyroscope detection module detection includes the following steps: (1) During initialization, collect static gyroscope data and complete calibration; (2) During the movement phase of the lifting table, the control box controls the motor to run according to the acceleration-constant speed-deceleration trajectory; (3) Collision and tilt determination: During the acceleration stage, the accelerometer function of the gyroscope is in a uniform acceleration state, and the anti-pinch judgment is suspended; when the predetermined speed is reached, if the gyroscope detects that the acceleration is close to zero and vibration or abnormal tilt angle occurs, anti-collision is triggered; in the soft collision scenario, the gyroscope tilt angle change rate is used to determine whether to perform emergency braking.

[0014] Further, the motor current detection module detection includes the following steps: (1) When the motor is running at a constant speed, the current data of the first 500ms is collected as a benchmark using a sliding average filter; (2) Calculate the current average current every 800ms and compare it with the reference value of the previous cycle; (3) If the current value exceeds the sum of the reference value and the preset sensitivity threshold for 100 ms, it is determined that there is an obstacle. (4) Trigger the motor to stop and run in reverse.

[0015] Further, the Hall sensor detection module detection includes the following steps: (1) When the motor runs at a constant speed, the PID control algorithm is used to maintain a constant speed; (2) Real-time collection of Hall sensor pulse width time. The theoretical value of a single-turn Hall pulse width is 4500us. (3) When 10 consecutive Hall pulse width data exceed 4800us, it is judged as abnormal resistance; (4) Trigger the motor to stop and run in reverse.

[0016] Furthermore, among the gyroscope detection module detection, the motor current detection module detection, and the Hall sensor detection module detection, once any detection mode is triggered, the other detection processes are immediately interrupted.

[0017] Compared with the prior art, the present invention has the following beneficial effects: it adopts gyroscope detection module detection, motor current detection module detection, and Hall sensor detection module detection to construct an integrated anti-pinch and anti-collision system, each of which can independently protect the system, and can continue to protect the system even if any protection measure fails, fundamentally overcoming the problem of uneven sensitivity caused by differences in transmission structure; it can be applicable to different steel frame structures, adaptive transmission resistance sizes and different loads, and the anti-pinch function is triggered more sensitively; it reduces the cost of adding various sensors such as pressure sensors in the lifting table. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the structure of the adaptive table frame of the present invention; Figure 2 This is a schematic diagram of the detection of the motor current detection module of the present invention; Figure 3 This is the motor current collection circuit diagram of the present invention; Figure 4 This is a detection schematic diagram of the Hall sensor detection module of the present invention, the horizontal axis represents the motor running time, the unit is milliseconds, and the vertical axis is the pulse width time, the unit is microseconds.

[0019] In the picture: 1 table leg, 2 base, 3 table top, 4 hand controller. DETAILED DESCRIPTION

[0020] like Figure 1As shown, an anti-pinch and anti-collision protection system in the form of an adaptive table frame structure, the adaptive table frame includes two liftable table legs 1, a base 2 is provided at the lower end of the table leg 1, a table board 3 is provided at the upper end, a control box is provided on the lower end surface of the table board 3, and also includes a hand controller 4, the table leg 1 is connected to a motor, a Hall sensor is provided in the motor, a gyroscope is provided in the control box, and an anti-pinch and anti-collision module is also provided in the control box, the anti-pinch and anti-collision module is electrically connected to the motor, the Hall sensor and the gyroscope, the anti-pinch and anti-collision module can control the motor to brake or reverse according to the status of the motor, the Hall sensor and the gyroscope, and the anti-pinch and anti-collision module includes a gyroscope detection module, a motor current detection module, and a Hall sensor detection module.

[0021] The gyroscope detection module is electrically connected to the gyroscope and determines the collision based on the acceleration, tilt angle or vibration data of the gyroscope.

[0022] The motor current detection module is electrically connected to the motor and identifies resistance by analyzing motor current changes through a filtering algorithm.

[0023] The Hall sensor detection module is electrically connected to the Hall sensor and determines an obstacle according to the continuous abnormality of the Hall sensor pulse width time.

[0024] 1. Gyroscope detection module detection: (1) System initialization and calibration The control box has a built-in 6-axis gyroscope (model MPU6050). After power-on, it collects acceleration data (X / Y / Z axes) in a stationary state and takes the average value for 1 second as the reference value to complete the initial calibration.

[0025] Motion trajectory control, the motor adopts S-shaped speed curve control, which is divided into three stages: acceleration-constant speed-deceleration Collision and tilt detection: Acceleration phase: The motor accelerates from rest to the target speed (e.g. 100 mm / s) with an acceleration of 0.5 m / s². At this time, the acceleration detected by the gyroscope matches the preset trajectory. Constant speed stage: the motor maintains a constant speed, the system acceleration returns to zero, and the gyroscope vibration detection function is activated; Speed ​​reduction phase: The motor stops at a deceleration of 0.3m / s², during which the anti-pinch detection is shielded.

[0026] Hard collision detection: During the constant speed phase, if the gyroscope detects an instantaneous acceleration exceeding 5g and lasting for more than 10ms, it is considered a hard collision and triggers emergency braking; Soft collision and tilt judgment: When the table tilt angle exceeds 2° (calculated by the gyroscope attitude angle), or the angle change rate is greater than 1° / s, it is judged as abnormal resistance and the motor runs in the reverse direction for 200ms and then stops.

[0027] 2. Motor current detection module detection, such as Figure 2 , 3 As shown: (1) The motor current detection module (ACS712 chip) samples the motor current in real time and performs AD conversion at a frequency of 10kHz. It uses a sliding average filter algorithm to store the current data of the previous 500ms. (2) Update the reference current value every 800ms. The calculation formula is: = K , where N = 500 sampling points, k represents the temporary variable in the summation process; (3) Set the sensitivity threshold to 15% of the reference current (default value). If the current value exceeds + , it is determined to be triggered by an obstacle, and the motor stops immediately and reverses for 2 seconds.

[0028] 3. Hall sensor detection module detection, such as Figure 4 As shown: (1) PID speed control, the motor adopts closed-loop PID control, parameters: =0.8, =0.05, =0.1, target speed is 111 rpm; (2) Theoretical value of Hall pulse width =4500us / pulse, Hall sensor (model AH49E) outputs 2 pulses per revolution, and the pulse width time is recorded in real time .

[0029] (3) Pulse width abnormality judgment: establish a circular buffer to store the latest 10 pulse width data, calculate the moving standard deviation σ, and if 10 consecutive pulse widths exceed 4800us (i.e. >1.06 ), and σ<50us (excluding instantaneous interference), it is judged as continuous resistance, triggering the motor to stop and reverse.

[0030] When any module is triggered, an interrupt signal is immediately sent to the control box and the detection threads of other detection modules are frozen. If the gyroscope fails, the system automatically switches to the "current + Hall" dual detection mode; the heartbeat packet interval of each module is 50ms. If it times out 3 times, it is judged as a hardware failure and enters a safety lock state.

[0031] Each of the three protection measures in this application can be turned on or off by setting, and the sensitivity level of each protection can be adjusted. After each trigger, a separate error code is displayed, and each item can protect the system independently. Even if any protection measure fails, the system can continue to be protected. What's more beneficial is that it is convenient for after-sales service to troubleshoot the problem. For example: if the angle anti-pinch and anti-collision are always triggered, it can be determined whether the entire table frame system is uneven. If it is always triggered by current, it may be caused by the unstable transmission resistance of the table frame, which is convenient for the later analysis of the product and makes the product safer and more reliable.

[0032] The above specific implementation methods are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the scope of the technical solutions of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. An anti-pinch and anti-collision protection system in the form of an adaptive table frame structure, the adaptive table frame includes two liftable table legs, a base is provided at the lower end of the table legs, a table top is provided at the upper end, a control box is provided at the lower end surface of the table top, and also includes a hand controller, characterized in that: The table leg is connected to a motor, a Hall sensor is arranged in the motor, a gyroscope is arranged in the control box, and an anti-pinch and anti-collision module is also arranged in the control box. The anti-pinch and anti-collision module is electrically connected to the motor, the Hall sensor and the gyroscope. The anti-pinch and anti-collision module can control the motor to brake or reverse according to the status of the motor, the Hall sensor and the gyroscope.

2. The anti-pinch and anti-collision protection system according to claim 1, characterized in that: The anti-pinch and anti-collision module includes a gyroscope detection module, a motor current detection module, and a Hall sensor detection module.

3. The anti-pinch and anti-collision protection system according to claim 2, characterized in that: The gyroscope detection module is electrically connected to the gyroscope and determines the collision based on the acceleration, tilt angle or vibration data of the gyroscope.

4. The anti-pinch and anti-collision protection system according to claim 3, characterized in that: The motor current detection module is electrically connected to the motor and identifies resistance by analyzing motor current changes through a filtering algorithm.

5. The anti-pinch and anti-collision protection system according to claim 4, characterized in that: The Hall sensor detection module is electrically connected to the Hall sensor and determines an obstacle according to the continuous abnormality of the Hall sensor pulse width time.

6. A detection method for an anti-pinch and anti-collision protection system according to any one of claims 1 to 5, characterized in that: The detection method achieves anti-pinch and anti-collision by at least one of the following methods:

1. Gyroscope detection module detection; 2. Motor current detection module detection; 3. Hall sensor detection module detection.

7. The detection method according to claim 6, characterized in that: The gyroscope detection module detection includes the following steps: (1) During initialization, collect static gyroscope data and complete calibration; (2) During the movement phase of the lifting table, the control box controls the motor to run according to the acceleration-constant speed-deceleration trajectory; (3) Collision and tilt determination: During the acceleration phase, the accelerometer function of the gyroscope is in a uniform acceleration state, and the anti-pinch determination is suspended. When the predetermined speed is reached, if the gyroscope detects that the acceleration is close to zero and vibration or abnormal tilt angle occurs, collision avoidance is triggered. In a soft collision scenario, the rate of change of the gyroscope tilt angle is used to determine whether emergency braking should be performed.

8. The detection method according to claim 7, characterized in that: The motor current detection module detection includes the following steps: (1) When the motor is running at a constant speed, the current data of the first 500ms is collected as a benchmark using a sliding average filter; (2) Calculate the current average current every 800ms and compare it with the reference value of the previous cycle; (3) If the current value exceeds the sum of the reference value and the preset sensitivity threshold for 100 ms, it is determined that there is an obstacle. (4) Trigger the motor to stop and run in reverse.

9. The detection method according to claim 8, characterized in that: The Hall sensor detection module detection includes the following steps: (1) When the motor runs at a constant speed, the PID control algorithm is used to maintain a constant speed; (2) Real-time collection of Hall sensor pulse width time. The theoretical value of a single-turn Hall pulse width is 4500us. (3) When 10 consecutive Hall pulse width data exceed 4800us, it is judged as abnormal resistance; (4) Trigger the motor to stop and run in reverse.

10. The detection method according to claim 6, characterized in that: When any one of the detection modes of the gyroscope detection module, the motor current detection module, and the Hall sensor detection module is triggered, the other detection processes are immediately interrupted.

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