Door and window emergency forced unlocking system

Abstract

The invention discloses a door and window emergency forced unlocking system, and relates to the technical field of door and window emergency unlocking. The standby power supply module is used for providing an independent emergency power supply for each door lock or window, and adopts a common dry battery to avoid danger caused by a lithium battery; the door and window emergency forced unlocking system and the door and window control system used in the normal state share the same group of manual switches; the time delay relay module is used for closing a time delay relay when the manual switch is pressed down and is kept for a set time; the motor driving circuit is directly connected with the output end of the time delay relay and a door and window control motor; and the time delay relay module is used for triggering an unlocking function after the switching operation exceeds the set time. The system and a door and window control system used in a normal state share the same group of manual switches, and the time delay relay is arranged to ensure that unlocking is triggered after a user continuously presses the switch for a time exceeding a set time, so that misoperation is prevented, and quick response under an emergency condition is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of emergency unlocking of doors and windows, and in particular to an emergency forced unlocking system for doors and windows. Background Art

[0002] Locking and unlocking mechanisms for doors and windows play a crucial role in the security systems of modern buildings and vehicles. Traditional door and window control systems typically rely on mains power and utilize electric actuators for remote or automatic control. However, these designs often lack effective emergency unlocking methods in emergencies such as fire, power outages, or system failures, potentially preventing timely evacuation and hindering the rapid intervention of external rescue forces.

[0003] For example, after a car falls into the water, a function may fail for some reason, such as detecting a high-current short circuit and having to cut off the power before the doors can unlock. Alternatively, wiring damage from a collision may prevent unlocking. Sometimes, a vehicle rolls over, and because the doors don't want to be flung open during a roll, the original vehicle control system won't issue an unlock command. However, after multiple rolls, the circuitry may be damaged, making it impossible to issue an unlock command when the car comes to a stop. Reports of collisions where all doors fail to unlock after a car crash, trapping drivers and passengers, resulting in tragic consequences, are common.

[0004] Therefore, it is particularly important to develop a door and window emergency forced unlocking system that is safe, reliable, easy to maintain, and can respond quickly in emergency situations. Summary of the Invention

[0005] The purpose of the present invention is to solve the shortcomings of the prior art and to propose an emergency forced unlocking system for doors and windows.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] Door and window emergency forced unlocking system, including:

[0008] Backup power module: provides independent emergency power for each door lock or window, using ordinary dry batteries to avoid the dangers of lithium batteries;

[0009] Manual switch: The door and window emergency forced unlocking system and the door and window control system used in normal state share the same set of manual switches;

[0010] Delay relay module: When the manual switch is pressed and held for the set time, the delay relay will be energized;

[0011] Motor drive circuit: directly connect the output end of the time delay relay and the door and window control motor;

[0012] The time delay relay module is used to trigger the unlocking function after the switch operation exceeds the set time;

[0013] The workflow is as follows:

[0014] Switch trigger: The user presses the switch from the inside and keeps it pressed;

[0015] Relay closure: If the switch signal remains for more than the set time, the delay relay will closure;

[0016] Door and window control motor works: The door and window control motor performs the unlocking operation.

[0017] Door and window emergency forced unlocking system, including:

[0018] Backup power module: provides independent emergency power for each door lock or window, using ordinary dry batteries to avoid the dangers of lithium batteries;

[0019] Delay relay module: triggers the unlocking function after the switch operation exceeds the set time;

[0020] Main control module: responsible for monitoring the status of each module and controlling the operation of the overall system;

[0021] Drive module: door and window control motor performs unlocking operation;

[0022] Monitoring module: real-time monitoring of system voltage and prompts battery replacement;

[0023] The time delay relay module is used to trigger the unlocking function after the switch operation exceeds the set time. Its working process is as follows:

[0024] Switch trigger: After the user presses the switch from the inside, the switch signal is transmitted to the main control module;

[0025] Delay setting: The main control module sets the delay parameters and continuously detects the switch signal during this period;

[0026] Delay relay energizes: If the switch signal remains on for more than the set time, the delay relay energizes and the door and window control motor performs the unlocking operation.

[0027] Preferably, the main control module is responsible for monitoring the status of each module and making corresponding control decisions; specifically including:

[0028] Power supply monitoring: Real-time monitoring of the voltage of the main power supply and backup power supply to ensure the stability of the system power supply;

[0029] Status monitoring: monitors the status of each door lock and window, including whether it is locked and whether there is an unlock request;

[0030] Emergency processing: When the main power failure is detected, switch to the backup power supply and start the delay relay module;

[0031] Fault diagnosis: diagnose faults in the system and provide feedback to the user through the monitoring module;

[0032] The driver module is responsible for performing the unlocking operation, as follows:

[0033] Based on the status monitoring of the main control module, the power supply is switched to the corresponding power supply; the driving module receives the control signal from the main control module and performs the corresponding unlocking operation according to the signal.

[0034] Preferably, the monitoring module monitors the voltage of the backup power supply in real time and provides a battery replacement prompt; specifically including:

[0035] Voltage monitoring: Continuously monitor the voltage of the backup dry battery and feed the voltage value back to the main control module;

[0036] Threshold setting: Based on the set voltage threshold, when the voltage is lower than the threshold, a replacement prompt is triggered.

[0037] Preferably, the circuit of the backup power supply is as follows:

[0038] Ordinary dry batteries are used as backup power sources. Multiple dry batteries are connected in series. The circuit includes an over-discharge protection circuit to prevent the battery from over-discharging. The backup power source is connected in parallel with the main power source through a time delay relay. When the main power source fails, it switches to the backup power source.

[0039] The time delay relay circuit is specifically as follows:

[0040] The control end of the relay is connected to the output interface of the main control module, and the main control module controls the attraction and release of the relay through high and low levels; a delay capacitor and resistor are added to the control circuit of the relay to set the delay time; when the switch in the car or indoor room remains on for more than the set time, the delay relay is attracted and the door and window control motor performs the unlocking operation.

[0041] Preferably: the main control module circuit is specifically as follows:

[0042] An STM32 series microcontroller is used as the main control chip. The VCC pin of the main control chip is connected to the main power supply and the backup power supply. The power supply source is selected through the power management circuit. The status signals of each door lock and window, as well as the voltage signal of the backup power supply, are collected and analog-to-digital conversion is performed through the ADC channel. Based on the written control program, the overall control logic of the system is implemented, including power switching, delay control, and fault diagnosis.

[0043] The driving module circuit is specifically as follows:

[0044] The L298N motor driver chip is used. The input ends of the driver chip are respectively connected to the main power supply and the backup power supply. The power source is selected by the control signal of the main control module. After receiving the control signal from the main control module, the door and window control motor performs the unlocking operation. Overcurrent protection and overtemperature protection circuits are added to prevent overload damage to the motor and driver chip.

[0045] Preferably, it also includes a power monitoring module and a control relay. When the backup power supply is switched, detection and switching are realized based on an intelligent switching circuit. The intelligent switching circuit includes a voltage comparator for monitoring changes in the power supply voltage. When the main power supply voltage is lower than a set threshold, the voltage comparator outputs a signal to control the relay to switch to the backup power supply.

[0046] A feedback loop is also included to ensure that the system automatically switches back to main power when main power is restored.

[0047] Preferably: the power monitoring module uses a voltage comparator to monitor the voltages of the main power supply and the backup power supply, and when the voltage of the main power supply is lower than a set threshold, the comparator outputs a high level signal;

[0048] The control relay receives the signal output by the comparator, and when low voltage is detected, the control relay switches to the backup power supply;

[0049] The feedback loop is specifically:

[0050] A diode and a resistor are added to the main power side of the relay to detect whether the main power has been restored. When the main power is restored, the diode conducts and sends a signal to the comparator input through the resistor, causing the system to switch back to the main power.

[0051] Preferably, the door and window emergency forced unlocking system further includes a state feedback circuit, and the state feedback circuit is specifically:

[0052] Connect an LED indicator light to both ends of the delay relay contact and use a resistor to limit the current; when the relay is closed, the LED lights up, indicating that the unlocking operation is in progress; when the relay is released, the LED goes out;

[0053] The main control module detects the brightness change of the LED through the ADC channel to obtain the status information of the relay;

[0054] The door and window emergency forced unlocking system also includes a high-efficiency motor drive circuit, specifically as follows:

[0055] MOSFET is used as a switch to control the on and off of the motor. A freewheeling diode is added to the drive circuit to prevent the motor's back electromotive force from damaging the MOSFET. An NTC thermistor is used to monitor the MOSFET's temperature. When the temperature exceeds the set threshold, the power supply is automatically cut off.

[0056] The specific connection method is as follows:

[0057] MOSFET is used as a switching tube to connect the two ends of the motor; the gate is connected to the main control module through a driver chip; a freewheeling diode is connected in parallel at both ends of the motor to prevent the motor's back electromotive force from damaging the MOSFET; a current detection resistor is connected in series between the source and drain of the MOSFET to monitor current changes; an NTC thermistor is placed near the MOSFET to monitor temperature changes; the main control module controls the conduction and shutdown of the MOSFET according to the monitored current and temperature values to achieve overcurrent protection and overtemperature protection.

[0058] Preferably, the door and window emergency forced unlocking system further includes a soft start circuit, which is constructed based on the capacitor charging principle. When the voltage across the capacitor gradually increases, the conduction degree of the MOSFET is controlled to achieve soft start of the current; specifically:

[0059] A charging capacitor and a charging resistor are connected in parallel at both ends of the motor; one end of the capacitor is connected to the power supply, and the other end is grounded through the charging resistor; a MOSFET is used to control the charging process of the capacitor; the gate is connected to the main control module through a driver chip; a synchronous rectifier diode is connected in parallel at both ends of the motor. When the MOSFET is turned on, the motor starts to charge; when the MOSFET is turned off, the motor continues to flow through the diode; the main control module controls the on-time of the MOSFET and the discharge process of the charging capacitor according to the preset soft-start curve to achieve soft-start of the current.

[0060] The beneficial effects of the present invention are:

[0061] 1. The system of the present invention shares the same set of manual switches with the door and window control system used in normal conditions. By setting a time-delay relay, it ensures that unlocking is triggered after the user continuously presses the switch for more than a set time, which not only prevents misoperation but also ensures a quick response in emergency situations.

[0062] 2. The present invention uses ordinary dry batteries as a backup power source to provide independent power supply for each door lock or window, effectively avoiding the safety risks that may be brought by lithium batteries, such as leakage and overheating, while reducing costs and maintenance difficulties.

[0063] 3. The present invention realizes intelligent switching between the main power supply and the backup power supply through a voltage comparator and a control relay, and automatically switches back when the main power supply is restored, ensuring continuous power supply and stability of the system; the design of the feedback loop further enhances the intelligence level of the system.

[0064] 4. The present invention takes safety into consideration in multiple aspects, from power supply selection, circuit design to fault diagnosis, status feedback, etc., ensuring that the system can operate safely and stably under various circumstances, providing strong protection for personnel evacuation and rescue. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] Figure 1 This is the main emergency unlocking logic circuit diagram;

[0066] Figure 2 Unlocks the circuit diagram for the example. DETAILED DESCRIPTION

[0067] The technical solution of the present invention will be further described in detail below in conjunction with specific implementation methods.

[0068] Example 1:

[0069] Door and window emergency forced unlocking system, including:

[0070] Backup power module: provides independent emergency power for each door lock or window, using ordinary dry batteries to avoid the dangers of lithium batteries;

[0071] Manual switch: The door and window emergency forced unlocking system and the door and window control system used in normal state share the same set of manual switches;

[0072] Delay relay module: When the manual switch is pressed and held for a set time (such as 5 seconds), the delay relay will be energized;

[0073] Motor drive circuit: directly connect the output end of the delay relay and the door and window control motor.

[0074] Wherein, the time delay relay module is used to trigger the unlocking function after the switch operation exceeds the set time;

[0075] The workflow is as follows:

[0076] Switch trigger: The user presses the switch from the inside and keeps it pressed;

[0077] Relay closure: If the switch signal remains for more than the set time, the delay relay will closure;

[0078] Door and window control motor works: the door and window control motor performs unlocking operation;

[0079] In daily use, the forced unlocking function will not be triggered by mistake because the holding time will not reach the time setting of the delay relay.

[0080] Example 2:

[0081] Door and window emergency forced unlocking system, including:

[0082] Backup power module: provides independent emergency power for each door lock or window, using ordinary dry batteries to avoid the dangers of lithium batteries;

[0083] Delay relay module: triggers the unlocking function after the switch operation exceeds the set time;

[0084] Main control module: responsible for monitoring the status of each module and controlling the operation of the overall system;

[0085] Drive module: door and window control motor performs unlocking operation;

[0086] Monitoring module: monitors system voltage in real time and prompts battery replacement.

[0087] The time delay relay module is used to trigger the unlocking function after the switch operation exceeds the set time. Its working process is as follows:

[0088] Switch trigger: After the user presses the switch from the inside, the switch signal is transmitted to the main control module;

[0089] Delay setting: The main control module sets a delay parameter (e.g. 5 seconds) and continuously detects the switch signal during this period;

[0090] Delay relay energizes: If the switch signal remains for more than the set time, the delay relay energizes and the door and window control motor performs the unlocking operation;

[0091] In daily use, the forced unlocking function will not be triggered by mistake because the holding time will not reach the time setting of the delay relay.

[0092] The main control module is responsible for monitoring the status of each module and making corresponding control decisions; specifically, it includes:

[0093] Power supply monitoring: Real-time monitoring of the voltage of the main power supply and backup power supply to ensure the stability of the system power supply;

[0094] Status monitoring: monitors the status of each door lock and window, including whether it is locked and whether there is an unlock request;

[0095] Emergency processing: When the main power failure is detected, switch to the backup power supply and start the delay relay module;

[0096] Fault diagnosis: Diagnose faults in the system and provide feedback to the user through the monitoring module.

[0097] The driver module is responsible for performing the unlocking operation, as follows:

[0098] Based on the status monitoring of the main control module, the power supply is switched to the corresponding power supply; the driving module receives the control signal from the main control module and performs the corresponding unlocking operation according to the signal.

[0099] The monitoring module monitors the voltage of the backup power supply in real time and provides a battery replacement prompt; specifically, it includes:

[0100] Voltage monitoring: Continuously monitor the voltage of the backup dry battery and feed the voltage value back to the main control module;

[0101] Threshold setting: Based on the set voltage threshold (e.g. 6V), when the voltage is lower than the threshold, a replacement prompt is triggered.

[0102] The backup power supply circuit is as follows:

[0103] Ordinary dry batteries are used as backup power sources. Multiple dry batteries are connected in series. The circuit includes an over-discharge protection circuit to prevent the battery from over-discharging. The backup power source is connected in parallel with the main power source through a time delay relay. When the main power source fails, it switches to the backup power source.

[0104] The time delay relay circuit is specifically as follows:

[0105] An SRD-05VDC-SL-C relay with an AC 250V / 5A contact capacity is selected. The control end of the relay is connected to the output interface of the main control module, which controls the closure and release of the relay through high and low voltage levels. A delay capacitor and resistor are added to the relay control circuit, and the delay time is set to 5 seconds. When the in-vehicle or indoor switch remains on for more than the set time (5 seconds), the delay relay closure is activated, and the door and window control motor performs the unlocking operation.

[0106] The main control module circuit is as follows:

[0107] An STM32 series microcontroller is selected as the main control chip. The VCC pin of the main control chip is connected to the main power supply and backup power supply, and the power supply source is selected through the power management circuit. The status signals of each door lock and window, the voltage signal of the backup power supply, etc. are collected, and analog-to-digital conversion is performed through the ADC channel. Based on the written control program, the overall control logic of the system is implemented, including power switching, delay control, fault diagnosis, etc.

[0108] The driving module circuit is specifically as follows:

[0109] The L298N motor driver chip is used. The input ends of the driver chip are respectively connected to the main power supply and the backup power supply. The power source is selected by the control signal of the main control module. After receiving the control signal from the main control module, the door and window control motor performs the unlocking operation. Overcurrent protection and overtemperature protection circuits are added to prevent overload damage to the motor and driver chip.

[0110] Example 3:

[0111] The door and window emergency forced unlocking system, based on Example 2, further includes a power monitoring module and a control relay. When the backup power source is switched, detection and switching are achieved based on an intelligent switching circuit. The intelligent switching circuit includes a voltage comparator for monitoring changes in the power supply voltage. When the main power supply voltage is lower than a set threshold, the voltage comparator outputs a signal to control the relay to switch to the backup power source.

[0112] A feedback loop is also included to ensure that the system automatically switches back to main power when main power is restored.

[0113] Among them, the power monitoring module uses a voltage comparator (such as LM393) to monitor the voltage of the main power supply and the backup power supply. When the main power supply voltage is lower than the set threshold, the comparator outputs a high-level signal;

[0114] The control relay receives the signal output by the comparator. When a low voltage is detected, the control relay switches to the backup power supply. A Darlington transistor (such as TIP122) can be used to drive the relay.

[0115] The feedback loop is specifically:

[0116] A diode and a resistor are added to the main power side of the relay to detect whether the main power has been restored. When the main power is restored, the diode conducts and sends a signal to the comparator input through the resistor, causing the system to switch back to the main power.

[0117] The door and window emergency forced unlocking system further includes a state feedback circuit, which is specifically:

[0118] Connect an LED indicator light to both ends of the delay relay contact and use a resistor to limit the current; when the relay is closed, the LED lights up, indicating that the unlocking operation is in progress; when the relay is released, the LED goes out;

[0119] The main control module detects the brightness change of the LED through the ADC channel to obtain the status information of the relay.

[0120] The door and window emergency forced unlocking system further includes a high-efficiency motor drive circuit, specifically as follows:

[0121] MOSFET is used as a switch to control the on and off of the motor. A freewheeling diode is added to the drive circuit to prevent the motor's back electromotive force from damaging the MOSFET. At the same time, to improve system reliability, overcurrent protection and overtemperature protection functions can be added to the drive circuit. For example, an NTC thermistor can be used to monitor the temperature of the MOSFET and automatically cut off the power supply when the temperature exceeds the set threshold.

[0122] The specific connection method is as follows:

[0123] Use MOSFET (such as IRLZ44N) as a switching tube to connect the two ends of the motor; the gate is connected to the main control module through a driver chip (such as TC4457); a freewheeling diode (such as IN4007) is connected in parallel at both ends of the motor to prevent the motor's back electromotive force from damaging the MOSFET; a current detection resistor is connected in series between the source and drain of the MOSFET to monitor current changes; an NTC thermistor (such as a negative temperature coefficient thermistor) is placed near the MOSFET to monitor temperature changes; the main control module controls the conduction and shutdown of the MOSFET based on the monitored current and temperature values to achieve overcurrent protection and overtemperature protection.

[0124] The door and window emergency forced unlocking system further includes a soft start circuit, which is constructed based on the capacitor charging principle. When the voltage across the capacitor gradually increases, the conduction degree of the MOSFET is controlled to achieve soft start of the current. Specifically:

[0125] A charging capacitor and a charging resistor are connected in parallel at both ends of the motor; one end of the capacitor is connected to the power supply, and the other end is grounded through the charging resistor; a MOSFET is used to control the charging process of the capacitor; the gate is connected to the main control module through a driver chip; a synchronous rectifier diode is connected in parallel at both ends of the motor. When the MOSFET is turned on, the motor starts to charge; when the MOSFET is turned off, the motor continues to flow through the diode; the main control module controls the on-time of the MOSFET and the discharge process of the charging capacitor according to the preset soft-start curve to achieve soft-start of the current.

[0126] in:

[0127] Soft start curve: Design a soft start curve based on the motor's characteristics and application requirements. For example, an exponential curve or ramp curve can be used to slowly increase the current.

[0128] PWM control: Use PWM signal to control the on-time of MOSFET; at the moment of startup, the duty cycle of PWM signal gradually increases, causing the current to rise slowly;

[0129] Feedback adjustment: In actual operation, the duty cycle of the PWM signal is dynamically adjusted according to the actual response of the motor to achieve the best soft start effect.

[0130] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. Door and window emergency forced unlocking system, characterized by: include: Backup power module: provides independent emergency power for each door lock or window, using ordinary dry batteries to avoid the dangers of lithium batteries; Manual switch: The door and window emergency forced unlocking system and the door and window control system used in normal state share the same set of manual switches; Delay relay module: When the manual switch is pressed and held for the set time, the delay relay will be energized; Motor drive circuit: directly connect the output end of the time delay relay and the door and window control motor; The time delay relay module is used to trigger the unlocking function after the switch operation exceeds the set time; The workflow is as follows: Switch trigger: The user presses the switch from the inside and keeps it pressed; Relay closure: If the switch signal remains for more than the set time, the delay relay will closure; Door and window control motor works: The door and window control motor performs the unlocking operation.

2. Door and window emergency forced unlocking system, characterized by: include: Backup power module: provides independent emergency power for each door lock or window, using ordinary dry batteries to avoid the dangers of lithium batteries; Delay relay module: triggers the unlocking function after the switch operation exceeds the set time; Main control module: responsible for monitoring the status of each module and controlling the operation of the overall system; Drive module: door and window control motor performs unlocking operation; Monitoring module: real-time monitoring of system voltage and prompts battery replacement; The time delay relay module is used to trigger the unlocking function after the switch operation exceeds the set time. Its working process is as follows: Switch trigger: After the user presses the switch from the inside, the switch signal is transmitted to the main control module; Delay setting: The main control module sets the delay parameters and continuously detects the switch signal during this period; Delay relay energizes: If the switch signal remains on for more than the set time, the delay relay energizes and the door and window control motor performs the unlocking operation.

3. The door and window emergency forced unlocking system according to claim 2, characterized in that: The main control module is responsible for monitoring the status of each module and making corresponding control decisions; specifically including: Power supply monitoring: Real-time monitoring of the voltage of the main power supply and backup power supply to ensure the stability of the system power supply; Status monitoring: monitors the status of each door lock and window, including whether it is locked and whether there is an unlock request; Emergency processing: When the main power failure is detected, switch to the backup power supply and start the delay relay module; Fault diagnosis: diagnose faults in the system and provide feedback to the user through the monitoring module; The driver module is responsible for performing the unlocking operation, as follows: Based on the status monitoring of the main control module, the power supply is switched to the corresponding power supply; the driving module receives the control signal from the main control module and performs the corresponding unlocking operation according to the signal.

4. The door and window emergency forced unlocking system according to claim 2, characterized in that: The monitoring module monitors the voltage of the backup power supply in real time and provides battery replacement prompts; specifically, it includes: Voltage monitoring: Continuously monitor the voltage of the backup dry battery and feed the voltage value back to the main control module; Threshold setting: Based on the set voltage threshold, when the voltage is lower than the threshold, a replacement prompt is triggered.

5. The door and window emergency forced unlocking system according to claim 2, characterized in that: The circuit of the backup power supply is specifically as follows: Ordinary dry batteries are used as backup power sources. Multiple dry batteries are connected in series. The circuit includes an over-discharge protection circuit to prevent the battery from over-discharging. The backup power source is connected in parallel with the main power source through a time delay relay. When the main power source fails, it switches to the backup power source. The time delay relay circuit is specifically as follows: The control end of the relay is connected to the output interface of the main control module. The main control module controls the contact and release of the relay through high and low levels. Delay capacitors and resistors are added to the control circuit of the relay to set the delay time. When the interior or exterior switch remains on for longer than the set time, the time delay relay is energized and the door and window control motor performs the unlocking operation.

6. The door and window emergency forced unlocking system according to claim 5, characterized in that: The main control module circuit is specifically as follows: An STM32 series microcontroller is used as the main control chip. The VCC pin of the main control chip is connected to the main power supply and the backup power supply. The power supply source is selected through the power management circuit. The status signals of each door lock and window, as well as the voltage signal of the backup power supply, are collected and analog-to-digital conversion is performed through the ADC channel. Based on the written control program, the overall control logic of the system is implemented, including power switching, delay control, and fault diagnosis. The driving module circuit is specifically as follows: The L298N motor driver chip is used. The input ends of the driver chip are respectively connected to the main power supply and the backup power supply. The power source is selected by the control signal of the main control module. After receiving the control signal from the main control module, the door and window control motor performs the unlocking operation. Overcurrent protection and overtemperature protection circuits are added to prevent overload damage to the motor and driver chip.

7. The door and window emergency forced unlocking system according to claim 2, characterized in that: It also includes a power monitoring module and a control relay. When the backup power supply is switched, detection and switching are achieved based on an intelligent switching circuit. The intelligent switching circuit includes a voltage comparator for monitoring changes in the power supply voltage. When the main power supply voltage is lower than a set threshold, the voltage comparator outputs a signal to control the relay to switch to the backup power supply. A feedback loop is also included to ensure that the system automatically switches back to main power when main power is restored.

8. The door and window emergency forced unlocking system according to claim 7, characterized in that: The power monitoring module uses a voltage comparator to monitor the voltage of the main power supply and the backup power supply. When the main power supply voltage is lower than a set threshold, the comparator outputs a high level signal; The control relay receives the signal output by the comparator, and when low voltage is detected, the control relay switches to the backup power supply; The feedback loop is specifically: A diode and a resistor are added to the main power side of the relay to detect whether the main power has been restored. When the main power is restored, the diode conducts and sends a signal to the comparator input through the resistor, causing the system to switch back to the main power.

9. The door and window emergency forced unlocking system according to claim 8, characterized in that: The door and window emergency forced unlocking system further includes a state feedback circuit, which is specifically: Connect an LED indicator light to both ends of the delay relay contact and use a resistor to limit the current; when the relay is closed, the LED lights up, indicating that the unlocking operation is in progress; when the relay is released, the LED goes out; The main control module detects the brightness change of the LED through the ADC channel to obtain the status information of the relay; The door and window emergency forced unlocking system also includes a high-efficiency motor drive circuit, specifically as follows: MOSFET is used as a switch to control the on and off of the motor. A freewheeling diode is added to the drive circuit to prevent the motor's back electromotive force from damaging the MOSFET. An NTC thermistor is used to monitor the MOSFET's temperature. When the temperature exceeds the set threshold, the power supply is automatically cut off. The specific connection method is as follows: MOSFET is used as a switching tube to connect the two ends of the motor; the gate is connected to the main control module through a driver chip; a freewheeling diode is connected in parallel at both ends of the motor to prevent the motor's back electromotive force from damaging the MOSFET; a current detection resistor is connected in series between the source and drain of the MOSFET to monitor current changes; an NTC thermistor is placed near the MOSFET to monitor temperature changes; the main control module controls the conduction and shutdown of the MOSFET according to the monitored current and temperature values to achieve overcurrent protection and overtemperature protection.

10. The door and window emergency forced unlocking system according to claim 9, characterized in that: The door and window emergency forced unlocking system also includes a soft start circuit, which is constructed based on the capacitor charging principle. When the voltage across the capacitor gradually increases, the conduction degree of the MOSFET is controlled to achieve soft start of the current; specifically: Connect a charging capacitor and a charging resistor in parallel at both ends of the motor; one end of the capacitor is connected to the power supply, and the other end is grounded through the charging resistor; use MOSFET to control the charging process of the capacitor; The gate is connected to the main control module through the driver chip; a synchronous rectifier diode is connected in parallel at both ends of the motor. When the MOSFET is turned on, the motor starts to charge; when the MOSFET is turned off, the motor continues to flow through the diode; the main control module controls the on-time of the MOSFET and the discharge process of the charging capacitor according to the preset soft-start curve to achieve soft-start of the current.

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