Switch control method of intelligent door lock and door lock mechanism

Abstract

The invention discloses a switch control method of an intelligent door lock, which comprises the following steps of: detecting a large current value and a timely voltage value of a motor in a locked-rotor state by using a controller, calculating internal resistance, sampling and recording power supply voltage and current of a driving motor at a time interval of 100-500 microseconds, calculating mechanical energy of each sampling and recording value, and calculating the mechanical energy of each sampling and recording value; summing all the calculated mechanical energy to obtain a mechanical energy total value, and then solving an average value; the average value of the total mechanical values serves as a threshold value for judging whether the motor operates in place or not, if the current total mechanical energy value is larger than or equal to the threshold value, it is judged that the door lock is locked, and the controller controls the motor to stop operating. According to the control method, other hardware equipment is not added, the machine can be stopped in time before motor stalling, electric energy is effectively saved, and the service time of the door lock is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent door lock switch control, and in particular to an intelligent door lock switch control method and a door lock mechanism. Background Art

[0002] At present, smart door locks realize switch control by rotating the motor to drive the lock core. In order to ensure that the lock core rotates in place, current detection is generally used to determine whether it is locked in place. The principle is that after the motor turns to the lock position, it is allowed to continue to stall for a period of time. When the motor stalls, the current value suddenly increases and a large current appears. When the controller detects a large current, it controls it to stop rotating. The rotation of the motor of the smart door lock can be divided into three states: the starting state of the motor, the rotating state of the motor, and the motor stalled state when the lock core is locked in place. From the perspective of electric energy conversion, electric energy is converted into mechanical energy and internal energy in the starting state and the rotating state, while the mechanical energy is almost converted into internal energy in the stalled state. Therefore, avoiding or reducing the stalled state can effectively save electric energy. A Chinese patent (publication number CN115749460A) discloses a switch method and door lock mechanism of an intelligent door lock, which calculates the number of motor rotations when the door lock mechanism switch does not generate a stall current by adding a Hall sensor, and counts the number of motor stalled rotations when each switch generates a stall current; calculates the difference between the total number of motor rotations and the number of motor stalled rotations at each switch; determines the number of motor rotations based on multiple differences in the number of rotations, and when the number of motor rotations reaches a certain number of rotations, the controller starts and stops the motor according to the number of rotations, thereby avoiding energy waste during stalling. However, this technical solution requires the installation of a Hall sensor to be implemented, and the biggest disadvantage of judging whether the lock is in place based on the number of rotations is that once the sensor installation position is offset or fails, the method will completely fail. Summary of the invention

[0003] The purpose of the present invention is to detect the current during the operation of the motor through the existing controller of the smart door lock without adding other hardware devices, and to calculate whether the lock is in place with the help of an algorithm, thereby reducing energy waste and extending the use time of the door lock.

[0004] In order to achieve the purpose of the present invention, the following technical solutions are proposed:

[0005] A method for controlling the opening and closing of an intelligent door lock, characterized in that:

[0006] S1, start the motor and detect the current I and voltage U of the drive motor through the controller. When a large current in the motor stall state is detected, the collected current value I0 and voltage value U0 are recorded, and the internal resistance R=U0 / I0 is calculated;

[0007] S2. Restart the motor to run. The controller samples and records the power supply voltage U and current I of the drive motor at time intervals t of 100 - 500 μs. When detecting a large current in the motor stall state, stop sampling and recording and do not record the last sampled value.

[0008] S3. Calculate the mechanical energy W of each sampled value. The mechanical energy W is obtained by subtracting the internal energy from the electrical energy. The calculation formula is W = UIt - I 2 Rt, where U is the recorded voltage value, I is the recorded current value, t is the time interval value determined in step S2, and R is the value obtained in step S1. Then sum all the calculated mechanical energies to obtain the total mechanical energy value ∑w.

[0009] S3. After 5 - 10 motor runs, then sum the total mechanical energy values ∑w of each motor run and divide by the number of motor runs to obtain the average value of the total mechanical energy.

[0010] S4. Take the average value of the total mechanical energy as the threshold for whether the motor runs in place. If the current total mechanical energy value ∑w is greater than or equal to the threshold, it is determined that the door lock has been locked, and the controller controls the motor to stop running.

[0011] Preferably, the time interval t in step S2 is 100 μs. The shorter the sampling time interval, the more accurate the final calculation result, but the relationship between data storage space and calculation amount also needs to be balanced.

[0012] Preferably, the number of motor runs in step S3 is the number of times of opening and closing the door. The larger the number of times, the more accurate the final calculation result. The specific number of times is set in the program before leaving the factory. According to the actual situation during the installation of the door lock, the number of times is set to 10 times as the best.

[0013] A door lock mechanism includes a lock core, a gearbox, a drive motor, and a controller;

[0014] The gearbox is fixedly connected to the lock core, and the rotation of the lock core is controlled by the shaft ring on the gearbox;

[0015] The drive motor is fixedly installed at the input shaft position of the gearbox and is connected to the input shaft of the gearbox through the motor shaft of the drive motor;

[0016] The drive motor leads out a control line and is connected to the controller, and the controller is used to execute the control method as described in S1 - S5.

[0017] Compared with the prior art, the technical solution of the present invention does not add a Hall sensor, reducing the assembly process in the production process, thereby reducing the overall cost, and at the same time avoiding control failure caused by sensor failure. During the operation of the motor, the current value and voltage value are changing, but the total mechanical energy value of the driving motor remains unchanged. Based on this principle, the total mechanical energy value of the motor from startup to just before stalling is calculated, and this total mechanical energy value is used as a threshold to judge the operation of the motor, so that the motor can be stopped before stalling occurs, thereby realizing motor control without stalling, effectively saving electric energy and prolonging the service time of the door lock. Detailed implementation manners

[0018] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the scope of protection of the present invention.

[0019] From the perspective of the existing intelligent door lock that only uses current detection to judge whether it is locked, the stalling phenomenon has actually occurred, that is, a certain amount of electric energy has been wasted. Therefore, the ideal way is to control the motor to stop running before the stalling is about to occur, so that the door lock is locked and the motor will not stall.

[0020] Embodiment 1: After the lock body of the embodiment of the present invention is installed, the door is opened and closed. During this process, the lock tongue has a process of squeezing inward and then popping out. At this time, the controller starts to implement the following steps:

[0021] S1. The controller detects the current I and voltage U of the driving motor. When detecting the large current in the motor stalling state, record the collected current value I0 and voltage value U0, and calculate the internal resistance R = U0 / I0; generally, the normal current of the motor rotation is about 300 - 500 mA, while the stalling current is generally above 1000 mA, and the maximum may reach 5000 mA. Therefore, the sudden increase in current can be judged by the detection circuit. The purpose of this step is to measure the internal resistance R, and the measurement of the internal resistance R can also be completed during the production process or quality inspection process before the door lock leaves the factory.

[0022] S2. In the engineering mode, that is, during the installation process of the door lock, the motor is started to run through the door opening and closing actions. The controller samples and records the power supply voltage U and current I of the driving motor at a time interval t of 100 μs, and records the voltage values as U1, U2, U3... U n , and at the same time records the current values as I1, I2, I3... In When a large current in the motor stall state is detected, stop sampling and recording and do not record the last sampled value; generally, the total time for the motor to start and lock is about 2S. If the time interval is 100 μs, the number of sampling records is about 10,000 times.

[0023] S3. Calculate the mechanical energy W of each sampled value. The mechanical energy W is obtained by subtracting the internal energy from the electrical energy. Based on the data obtained in the previous steps, through the calculation formula W1 = U1I1t - I1 2 Rt to get W1, and then similarly get W2, W3... W n Then add W1, W2, W3... W n together to obtain the total mechanical energy value ∑w; during the operation of the motor, the current value I and the voltage value U are changing, but the total mechanical energy value for driving the motor remains unchanged. Therefore, through this calculation process, the total mechanical energy value of the motor from start to lock can be calculated.

[0024] S3. Through 5 door opening and closing operations, that is, 5 motor operations, then add up the total mechanical energy values ∑w of the 5 motor operations and divide by the number of motor operations 5 to obtain the average value of the total mechanical value

[0025] S4. Exit the engineering mode, and the controller will use the average value of the total mechanical value as the threshold for whether the motor operation is in place. During the subsequent door opening and closing process, the controller continues to sample the voltage and current of the driving motor and calculate the mechanical energy. If the current total mechanical energy value is greater than or equal to the threshold, it is determined that the door lock has been locked, and the controller controls the motor to stop running.

[0026] During use, if the situation where the door lock is actually not locked in place but the motor has stopped running occurs, it can be set by entering the administrator mode and re - executing the above steps S1 - S4 to correct the threshold.

[0027] Before exiting the engineering mode, during the data sampling of each door opening and closing process, the motor stall actually occurs. However, after exiting the engineering mode, through the setting of the threshold, the motor can be stopped before the stall occurs, effectively saving electrical energy. Existing intelligent door locks are powered by dry batteries or rechargeable batteries, and generally need to replace the batteries or recharge after 3 - 6 months of use. After adopting this sampling control method, the service time can be effectively extended.

[0028] This embodiment also provides a door lock mechanism, including a lock core, a gearbox, a driving motor, and a controller; the gearbox is fixedly connected to the lock core, and the shaft ring on the gearbox controls the rotation of the lock core; the driving motor is fixedly installed at the input shaft position of the gearbox and is connected to the input shaft of the gearbox through the motor rotating shaft of the driving motor; the driving motor leads out a control line and is connected to the controller, and the controller is used to execute the control method described in S1-S5.

[0029] Embodiment 2: The basic steps of this embodiment are the same as those of Embodiment 1, where the sampling time interval is set to 500 μs, and the number of door openings and closings in the engineering mode is set to 10 times. By means of this embodiment, the service life of the door lock can be effectively extended.

[0030] Embodiment 3: The basic steps of this embodiment are the same as those of Embodiment 1, where the sampling time interval is set to 300 μs, and the number of door openings and closings in the engineering mode is set to 8 times. By means of this embodiment, the service life of the door lock can be effectively extended.

[0031] Although the embodiments of the present invention have been described in combination, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A method for controlling the opening and closing of an intelligent door lock, characterized in that: S1. Start the motor to run and detect the current I and voltage U of the driving motor through a controller. When a large current in the motor locked-rotor state is detected, record the collected current value I0 and voltage value U0, and calculate the internal resistance R = U0 / I0; S2. Restart the motor to run, and sample and record the power supply voltage U and current I of the driving motor at a time interval t of 100 - 500 μs through the controller. When a large current in the motor locked-rotor state is detected, stop sampling and recording and do not record the last sampling record value; S3. Calculate the mechanical energy W of each sampled recorded value. The mechanical energy W is obtained by subtracting the internal energy from the electrical energy, and the calculation formula is W = UIt - I 2 Rt, where U is the recorded voltage value, I is the recorded current value, t is the time interval value determined in step S2, and R is the value obtained in step S1. Then sum all the calculated mechanical energies to obtain the total mechanical energy value ∑w; S3. After the motor runs 5 to 10 times, sum up the total mechanical energy value ∑w of each motor run, and then divide it by the number of motor runs to obtain the average value of the total mechanical value. S4. Take the average value of the total mechanical value as the threshold for whether the motor operation is in place. If the current total mechanical energy value ∑w is greater than or equal to the threshold, it is determined that the door lock has been locked, and the controller controls the motor to stop running.

2. The switch control method of an intelligent door lock according to claim 1, wherein: The time interval t in step S2 is 100 μs.

3. The switch control method of an intelligent door lock according to claim 1, characterized in that: The number of motor running times in step S3 is the number of door opening and closing times, and the value is 10.

4. A door lock mechanism, comprising a lock core, a gearbox, a driving motor and a controller; characterized in that: The gearbox is fixedly connected to the lock core, and the rotation of the lock core is controlled by the shaft ring on the gearbox; The driving motor is fixedly installed at the input shaft position of the gearbox and is connected to the input shaft of the gearbox through the motor shaft of the driving motor; The driving motor leads out a control line and is connected to the controller, and the controller is used to execute the control method according to any one of claims 1 - 3.