Automatic timing maintenance device for elevator emergency power supply

Abstract

The utility model provides an automatic timing maintenance device for an elevator emergency power supply. The automatic maintenance device comprises a maintenance control module, and a presence / absence detection sensor and a power-off time presetting module which are connected with the maintenance control module, the presence and absence detection sensor comprises an ultrasonic obstacle avoidance sensor which is arranged at a ceiling of an elevator car and used for detecting whether a person exists in the car, and the maintenance control module comprises a timing maintenance contactor KM used for testing the emergency leveling device, a small relay KA1 and a control circuit comprising a small relay KA2. When the maintenance timing time stored in the power-off time presetting module is up and the ultrasonic obstacle avoidance sensor detects that no one is in the lift car, the maintenance control module cuts off the mains supply of the elevator through the machine room main power switch so as to start the emergency power supply of the elevator; and meanwhile, internal wiring of the elevator car operating panel is controlled to enable the car to move to a preset floor for maintenance operation, and the elevator emergency power supply can be automatically maintained at regular time.

Description

Technical Field

[0001] This utility model relates to the field of elevator operation and maintenance technology, and in particular to an automatic timed maintenance device for elevator emergency power supplies. Background Technology

[0002] Currently, elevators are equipped with emergency power supplies for power outages. When the mains power fails, the emergency power supply automatically activates, providing three-phase emergency power to the elevator control system, allowing the elevator car to slowly move to the landing position and open the doors to release passengers. The elevator's power outage re-leveling function relies on an emergency power source (such as a battery). However, prolonged disuse or lack of regular maintenance can lead to battery aging or failure. Since battery maintenance relies on manual operation, there are risks of missed checks, insufficient testing frequency, or improper operation. Furthermore, the lack of automated testing methods makes it impossible to ensure that the emergency power supply is always available.

[0003] The elevator emergency power supply timed automatic maintenance device proposed in this utility model can simulate a power grid outage when the elevator is idle and no one is in the car, so that the emergency power supply can be put into use and in a charging and discharging state. It can automatically select the highest floor to run. During the operation, it records various parameters of the emergency power supply battery, such as the voltage of each battery unit, the surface temperature of the battery, the total current of the battery charging and discharging circuit, maintenance time and frequency, maintenance status, and operational faults. The collected information is sent to the Internet of Things platform through the network communication module. Maintenance personnel can monitor the real-time use of the emergency power supply on their mobile phones or computers, understand the various parameters of the battery, and replace the battery in time if a problem is found. Utility Model Content

[0004] This utility model proposes a timed automatic maintenance device for elevator emergency power supplies, which can perform timed automatic maintenance on elevator emergency power supplies.

[0005] The present invention adopts the following technical solution.

[0006] An elevator emergency power supply timed automatic maintenance device includes a maintenance control module and connected to it an occupancy detection sensor and a power outage time preset module. The occupancy detection sensor includes an ultrasonic obstacle avoidance sensor installed on the elevator car ceiling to detect whether there are people in the car. The maintenance control module includes a timed maintenance contactor KM, a small relay KA1, and a control circuit containing a small relay KA2 for testing the emergency leveling device. When the maintenance time stored in the power outage time preset module expires and the ultrasonic obstacle avoidance sensor detects that there is no one in the car, the maintenance control module cuts off the elevator's mains power supply via the machine room main power switch to start the elevator's emergency power supply. At the same time, it controls the internal wiring of the elevator car control panel to move the car to a preset floor for maintenance work.

[0007] The power outage time preset module uses an STM32F103C8T6 as the MCU. The MCU's internal real-time clock RTC is used to set the preset time in years, months, days, hours, minutes, and seconds, and the settings are displayed on the LCD connected to the MCU. The external small relay KA1 is used for mode switching. The mode switching is set to occur during the elevator's idle time. The modes are divided into normal operation mode and timed maintenance mode.

[0008] The power-off time preset module MCU's level signal powers the small intermediate relay KA1 through the optocoupler.

[0009] When the maintenance timer stored in the power outage timer preset module expires and the ultrasonic obstacle avoidance sensor detects that no one is in the car, the power outage timer preset module's level signal energizes the small intermediate relay KA1. In conjunction with the automatic triggering action of the timed maintenance contactor KM, the main power switch in the machine room cuts off the elevator's mains power supply to start the elevator's emergency power supply. At the same time, the small relay KA2 controls the internal wiring of the elevator car control panel to move the car to the preset floor for maintenance work.

[0010] After the power outage time preset module cuts off the mains power supply to the elevator via the main power switch in the machine room to activate the elevator's emergency power supply, the small relay KA2 controls the internal wiring of the elevator car control panel to move the car to the preset floor for maintenance work. This is achieved by short-circuiting the internal wiring contacts of the elevator car control panel to simulate the triggering of the floor buttons on the elevator car control panel.

[0011] The emergency leveling device is an elevator power failure re-leveling device with a built-in emergency power supply, which uses multiple sets of lead-acid batteries as energy storage devices.

[0012] The automatic maintenance device also includes a battery parameter acquisition module for collecting data on the voltage, temperature, and total charging and discharging current of each unit of the emergency power lead-acid battery.

[0013] The battery parameter acquisition module acquires the voltage of each cell of the emergency power lead-acid battery through a voltage acquisition circuit containing a resistor voltage divider circuit and an LTC248 multiplexing chip.

[0014] The battery parameter acquisition module collects the temperature of each cell of the emergency power lead-acid battery through a cell temperature acquisition board attached to the surface of the battery. The cell temperature acquisition board is equipped with a temperature sensor LM35.

[0015] The battery parameter acquisition module uses the Hall effect current sensor ACS758 to acquire the total current signal of the emergency power supply charging and discharging circuit.

[0016] The emergency leveling device also includes a network communication module for accessing an Internet of Things (IoT) platform.

[0017] The elevator emergency power supply timed automatic maintenance device proposed in this utility model can simulate a power outage when the elevator is idle and no one is in the car, enabling the emergency power supply to be put into use and in a charging and discharging state. It can automatically select the highest floor to run on. During operation, it records various parameters of the emergency power supply battery, such as the voltage of each battery unit, the surface temperature of the battery, the total current of the battery charging and discharging circuit, maintenance time and frequency, maintenance status, and operational faults. The collected information is sent to an external Internet of Things platform through a network communication module, allowing maintenance personnel to monitor the real-time usage of the emergency power supply, understand various battery parameters, and replace any batteries with problems in a timely manner. Attached Figure Description

[0018] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0019] Figure 1 This is a schematic diagram of the pin distribution of the STM32F103C8T6 of the power-off time preset module in this embodiment of the present invention.

[0020] Figure 2 This is a schematic diagram of the high-frequency crystal oscillator circuit of the power-off time preset module in this embodiment of the present invention;

[0021] Figure 3 This is a circuit diagram of the low-frequency crystal oscillator circuit of the power-off time preset module in this embodiment of the present invention;

[0022] Figure 4 This is a schematic diagram of the reset circuit of the power-off time preset module in an embodiment of this utility model;

[0023] Figure 5 This is a circuit diagram of the system power supply of the power-off time preset module in an embodiment of this utility model;

[0024] Figure 6 This is a schematic diagram of the backup battery wiring of the power outage time preset module in this embodiment of the utility model;

[0025] Figure 7 This is a schematic diagram of the LCD1602 display module of the power outage time preset module in an embodiment of this utility model;

[0026] Figure 8 This is a schematic diagram of the peripheral circuit of the LCD1602 display module of the power failure time preset module in this embodiment of the present invention;

[0027] Figure 9 This is a schematic diagram of the function button circuit of the power failure time preset module in this embodiment of the utility model;

[0028] Figure 10This is a schematic diagram of the main circuit for switching between mains power and emergency power in an embodiment of this utility model;

[0029] Figure 11 This is a schematic diagram of the timed maintenance mains power and emergency power switching control circuit in this embodiment of the utility model;

[0030] Figure 12 This is a schematic diagram of the linkage circuit between the maintenance control module and the elevator car in a simulated state (maintenance state) according to an embodiment of this utility model;

[0031] Figure 13 This is a schematic diagram of the presence or absence detection module in the car in an embodiment of this utility model;

[0032] Figure 14 This is a partial wiring diagram of the car occupancy detection module in this embodiment of the utility model;

[0033] Figure 15 This is a schematic diagram of the installation position of the car occupancy detection module in this embodiment of the utility model;

[0034] Figure 16 This is a schematic diagram of the voltage acquisition circuit of the battery parameter acquisition module in an embodiment of this utility model;

[0035] Figure 17 This is a schematic diagram of the unit voltage acquisition board of the voltage acquisition circuit of the battery parameter acquisition module in this embodiment of the present invention;

[0036] Figure 18 This is a schematic diagram of the battery voltage and temperature acquisition multiplexing circuit of the battery parameter acquisition module in this embodiment of the utility model;

[0037] Figure 19 This is a schematic diagram of the unit temperature acquisition board of the battery parameter acquisition module in an embodiment of this utility model;

[0038] Figure 20 This is a schematic diagram of the data acquisition point setting of the battery parameter acquisition module in this embodiment of the utility model;

[0039] Figure 21 This is an electrical control schematic diagram of the emergency power supply timed maintenance device of this utility model;

[0040] Figure 22 This is a schematic diagram of a battery parameter acquisition module used for voltage acquisition circuit of 16-channel batteries in an embodiment of this utility model.

[0041] Figure 23 This is a schematic diagram of a battery parameter acquisition module used for temperature acquisition circuit of 16-channel batteries in this embodiment of the utility model. Detailed Implementation

[0042] As shown in the figure, the elevator emergency power supply timed automatic maintenance device includes a maintenance control module and connected to it an occupancy detection sensor and a power outage time preset module. The occupancy detection sensor includes an ultrasonic obstacle avoidance sensor installed on the elevator car ceiling to detect whether there are people in the car. The maintenance control module includes a timed maintenance contactor KM, a small relay KA1, and a control circuit containing a small relay KA2 for testing the emergency leveling device. When the maintenance time stored in the power outage time preset module expires and the ultrasonic obstacle avoidance sensor detects that there is no one in the car, the maintenance control module cuts off the elevator's mains power supply via the machine room main power switch to start the elevator's emergency power supply. At the same time, it controls the internal wiring of the elevator car control panel to move the car to a preset floor for maintenance work.

[0043] The power outage time preset module uses an STM32F103C8T6 as the MCU. The MCU's internal real-time clock RTC is used to set the preset time in years, months, days, hours, minutes, and seconds, and the settings are displayed on the LCD connected to the MCU. The external small relay KA1 is used for mode switching. The mode switching is set to occur during the elevator's idle time. The modes are divided into normal operation mode and timed maintenance mode.

[0044] The power-off time preset module MCU's level signal powers the small intermediate relay KA1 through the optocoupler.

[0045] The power outage time setting module mainly sets the time and timed power outage parameters. The year, month, day, hour, minute, and second are set via function buttons and displayed on the LCD. Typically, the timer is set to the middle or late part of each month, between 3:00 AM and 4:00 AM, during the elevator's idle time and when the elevator car is unoccupied, to simulate a power outage scenario.

[0046] like Figure 1 As shown, the preset value module mainly uses STM32F103C8T6 as the MCU. The internal real-time clock (RTC) is used to set the year, month, day, hour, minute and second of the time and display it on the LCD. It uses an externally connected small relay for mode switching and is configured to automatically trigger two maintenance cycles per month (the specific time can be set). It is generally set to switch modes during the elevator's idle time. The modes are divided into normal operation mode and timed maintenance mode.

[0047] The timing module consists of a crystal oscillator circuit, a reset circuit, a system power supply, a backup power supply, an LCD1602 display module, and a function key module.

[0048] 1) Crystal oscillator circuit, such as Figure 2 As shown,

[0049] Crystal circuits include high-frequency crystals (such as 8MHz) and low-frequency crystals (such as 32.768kHz). The high-frequency crystal is used for the system master clock, while the low-frequency crystal may be used for the RTC (real-time clock) or low-power modes.

[0050] (1) Parameters of high frequency crystal oscillator circuit

[0051] Crystal oscillator model: 8MHz ±20ppm (e.g., ECS-080-20-4X-DU)

[0052] Load capacitance (CL):

[0053] Determined according to the crystal oscillator datasheet, for example, CL=20pF

[0054] Matching capacitor formula: C6 = C7 = 2 × CL - Cstray

[0055] (Cstray is the parasitic capacitance of the PCB, usually 3-5pF)

[0056] C6 = C7 = 2 × 20pF - 5pF = 35pF → Select a 33pF NP0 capacitor.

[0057] Feedback resistor (Rf): Typically 1MΩ (to suppress harmonics and enhance oscillation).

[0058] (2) Low-frequency crystal oscillator circuit, such as Figure 3 As shown,

[0059] Parameter configuration

[0060] Crystal oscillator model: 32.768kHz ±20ppm (e.g., EPSON MC-306 32.768KD20)

[0061] Load capacitance: CL = 12.5pF

[0062] C3 = C4 = 2 × 12.5pF - 5pF = 20pF → Select a 22pF C0G capacitor.

[0063] 2) Reset circuit, such as Figure 4 As shown,

[0064] The reset circuit consists of a capacitor connected in series with a resistor. The capacitor voltage cannot change abruptly. When the system is powered on, the microcontroller's RST pin will display a continuous high level, and the duration of this high level is determined by the capacitor value. The STM32 microcontroller will perform a reset operation after detecting a high level lasting longer than 20µs on its RST pin. Therefore, appropriately combining the RC values ​​can ensure a reliable reset.

[0065] 3) The system power supply circuit is as follows: Figure 5 As shown,

[0066] The microcontroller operates at 3.3V, so the voltage needs to be stepped down. The power supply is connected from the 5V output of the switching power supply to pin 1 of the AMS1117 forward voltage drop regulator, and pin 3 of the output terminal outputs 3.3V to supply the system power.

[0067] 4) Wiring of the backup battery as follows Figure 6 As shown,

[0068] Backup batteries are typically used to keep the RTC running and to back up the data in the registers when the main power is disconnected.

[0069] ①Main power priority mechanism

[0070] When the main power supply (VDD) is present: the RTC is powered by VDD through the internal circuit, the diode is reverse-biased and the battery does not consume power.

[0071] When the main power supply is disconnected: the battery supplies power to VBAT through a diode to maintain the operation of the RTC.

[0072] ② Current consumption requirements

[0073] Typical RTC operating current: Approximately 1μA (LSE clock source, uncalibrated)

[0074] Battery life calculation:

[0075] Lifespan (years) = Battery capacity (mAh) / (Operating current (μA) × 24 × 365 / 1000)

[0076] The lifespan of CR2032 (220mAh) is approximately 220 / (1 × 8.76) ≈ 25 years (theoretical value, actual lifespan is approximately 5-10 years).

[0077] The negative terminal of the backup battery is connected to system ground, and the positive terminal is connected to pin 1 of the STM32 chip.

[0078] 5) LCD1602 display module, such as Figure 7 As shown, the peripheral circuit of the LCD1602 display module is as follows: Figure 8 As shown,

[0079] The LCD1602 LCD screen is a 16-column, 2-row character LCD module, with each character consisting of a 5x8 dot matrix. It is primarily used for setting and displaying calendar and time parameters, allowing for settings of year, month, day, weekday, hour, minute, and second.

[0080] Main technical parameters of LCD1602:

[0081] 1. Display capacity: 16 x 2 characters

[0082] 2. Chip operating voltage: 4.5-5.5V

[0083] 3. Operating current: 2.0mA (5.0V)

[0084] 4. Module optimal operating voltage: 5.0V

[0085] 5. Character size: 2.95×4.35(W×H)mm.

[0086] 6) Function key circuit of the function key module, such as Figure 9 As shown,

[0087] The function key module is mainly used to set time and timing parameters. It consists of function keys, plus / minus keys, and a clear key.

[0088] S1, S2, S3, and S4 are used as ordinary key inputs and are connected to PA1, PA2, PA3, and PA4 respectively.

[0089] The maintenance control module includes a mains power indicator light, which is always on when the mains power supply is normal, and is off during maintenance.

[0090] The main function of the maintenance control module is to simulate a power outage when the set maintenance timer expires. At this time, when pin 32 PA11 of the main control chip outputs a high level, the optocoupler energizes the small intermediate relay KA1, which, in conjunction with the timed maintenance contactor KM, automatically cuts off the mains power, activating the emergency power supply. The elevator car's top floor button and the small relay KA2 then operate automatically in tandem. The mains power indicator light on the maintenance module is constantly lit under normal mains power conditions and is off during maintenance. This module primarily tests the emergency power supply to ensure it is functioning correctly and prevents failure in critical moments.

[0091] This module mainly consists of the main power switch for the computer room, a timed maintenance contactor KM, an emergency leveling device, small relays KA1 and KA2, control circuits, and power indicator lights.

[0092] Does the elevator car have an unoccupied detection module?

[0093] During scheduled maintenance, it is necessary to check whether there is anyone in the elevator car. If the car is unoccupied within the scheduled maintenance time, the mains power will be automatically cut off, the emergency power supply will be activated, the elevator can automatically select the highest floor, and then the door will close to start the scheduled maintenance program.

[0094] This device uses an ultrasonic obstacle avoidance sensor, which is installed on the ceiling of the car to detect whether the car is unoccupied.

[0095] 1) Functions: Supports normally open switch signal output; supports one-button setting of sensing distance, which is convenient, fast and efficient.

[0096] 2) Electrical parameters

[0097] ① Power supply voltage: DC 9-30V;

[0098] ② Output interface: Normally open switch signal output (closed when there is a signal, open when there is no signal)

[0099] ③ Effective detection distance: 20-4500mm

[0100] ④ Detection angle: 60° cone angle, large sensing area;

[0101] ⑤ Distance measurement accuracy: 5mm;

[0102] ⑥ Resolution: 1mm;

[0103] 3) Interface definition

[0104] Red: 9-30V Green: OUT

[0105] Black: GND; Yellow: COM.

[0106] When the maintenance timer stored in the power outage timer preset module expires and the ultrasonic obstacle avoidance sensor detects that no one is in the car, the power outage timer preset module's level signal energizes the small intermediate relay KA1. In conjunction with the automatic triggering action of the timed maintenance contactor KM, the elevator's mains power supply is cut off via the machine room's main power switch to activate the elevator's emergency power supply. Simultaneously, the small relay KA2 controls the internal wiring of the elevator car control panel to move the car to the preset floor for maintenance work. This is achieved by short-circuiting the internal wiring contacts of the elevator car control panel to simulate the triggering of the floor buttons on the elevator car control panel.

[0107] After the power outage time preset module cuts off the mains power supply to the elevator via the main power switch in the machine room to activate the elevator's emergency power supply, the small relay KA2 controls the internal wiring of the elevator car control panel to move the car to the preset floor for maintenance work.

[0108] The emergency leveling device is an elevator power failure re-leveling device with a built-in emergency power supply, which uses multiple sets of lead-acid batteries as energy storage devices.

[0109] The automatic maintenance device also includes a battery parameter acquisition module for collecting data on the voltage, temperature, and total charging and discharging current of each unit of the emergency power lead-acid battery.

[0110] The battery parameter acquisition module acquires the voltage of each cell of the emergency power lead-acid battery through a voltage acquisition circuit containing a resistor voltage divider circuit and an LTC248 multiplexing chip.

[0111] The battery parameter acquisition module collects the temperature of each cell of the emergency power lead-acid battery through a cell temperature acquisition board attached to the surface of the battery. The cell temperature acquisition board is equipped with a temperature sensor LM35.

[0112] The battery parameter acquisition module uses the Hall effect current sensor ACS758 to acquire the total current signal of the emergency power supply charging and discharging circuit.

[0113] The battery parameter module mainly collects the voltage, temperature, and total charging and discharging current of each unit of the lead-acid battery in the emergency power supply device.

[0114] 1) Target of data collection:

[0115] ① Unit Voltage: The single-terminal voltage (12V) of each battery unit consists of two groups of eight 12V batteries connected in series and parallel. If any of these groups fails, it may cause a malfunction before or during the use of the emergency power supply. The terminal voltage of each battery unit must be measured to ensure it is within the normal range.

[0116] ② Cell Temperature: Battery temperature monitoring is achieved through temperature sensors attached to the surface of each cell. The temperature of each cell is monitored in real time. Excessively high temperatures can affect battery life and safety, prompting maintenance personnel to replace the affected cells promptly.

[0117] ③ Total current: The total current data of the charging and discharging circuit can be used for fault diagnosis to determine whether there is an internal short circuit or whether the internal connection is reliable. Abnormal changes in current may occur earlier than changes in voltage and temperature. Early detection of faults allows for timely maintenance.

[0118] 2) Signal acquisition method

[0119] ① Battery unit voltage signal acquisition: The emergency power supply device is equipped with two sets of parallel circuits, each with eight units connected in series. The terminal voltage of each battery unit is 12V. A total of 16 battery units are monitored for their terminal voltage. The signal acquisition uses a resistor voltage divider + LTC248 multiplexing chip.

[0120] Voltage divider circuit: Voltage division calculation for each battery (12V→3.3V)

[0121] R1 = 10K, R2 = 3.3K→ Vout = 12V * R2 / (R1+R2) ≈ 3.0V

[0122] The LTC2498 is a 24-bit delta-Σ ADC supporting 16 input channels, featuring high accuracy and low noise. It operates from 2.7V to 5.5V, with a selectable 3.3V voltage range. Each channel of the LTC2498 is configured in single-ended mode. For the digital interface, the LTC2498 communicates with the MCU via an SPI interface. Overvoltage protection and filtering are implemented, with TVS diodes added at the input ports to prevent voltage transients.

[0123] The emergency leveling device also includes a network communication module for accessing an Internet of Things (IoT) platform.

[0124] ② Unit temperature signal acquisition

[0125] The battery cell temperature is acquired using LM35 temperature sensors attached to the surfaces of 16 individual battery cells, for a total of 16 temperature sensors. These sensors are analog temperature sensors, characterized by high linearity, simple circuitry, and ease of use.

[0126] ③ Total current signal acquisition

[0127] The total current signal acquisition of the charging and discharging circuit uses the ACS758, which is a Hall effect current sensor. Its advantages are isolated measurement and suitability for high current and high voltage applications.

[0128] The main function of the network communication module is to connect to an external Internet of Things (IoT) platform and transmit data and status such as the voltage of the batteries in the emergency power supply device, the total current of the charging and discharging circuit, the temperature of each battery, and maintenance time in real time for remote monitoring. Maintenance personnel can connect to the IoT platform via mobile phone to understand the operation of the emergency power supply device in real time, which facilitates maintenance and management.

[0129] The network communication module uses the W5500 chip, which integrates the TCP / IP protocol; it has an internal 32K-byte memory as a TX / RX cache; it supports a transmission rate of 10 / 100Mbps; it supports simultaneous operation of 8 independent ports; the module supports 3.3V or 5V power supply; and the communication method between the module and the microcontroller system is simple and convenient SPI communication.

Claims

1. An elevator emergency power supply timed automatic maintenance device, characterized in that: The automatic maintenance device includes a maintenance control module and connected to it an occupancy detection sensor and a power outage time preset module. The occupancy detection sensor includes an ultrasonic obstacle avoidance sensor installed on the elevator car ceiling to detect whether there are people in the car. The maintenance control module includes a timed maintenance contactor KM, a small relay KA1, and a control circuit containing a small relay KA2 for testing the emergency leveling device. When the maintenance timer stored in the power outage time preset module expires and the ultrasonic obstacle avoidance sensor detects that there is no one in the car, the maintenance control module cuts off the mains power supply to the elevator via the main power switch in the machine room to start the elevator's emergency power supply. At the same time, it controls the internal wiring of the elevator car control panel to move the car to a preset floor for maintenance work.

2. The elevator emergency power supply timed automatic maintenance device according to claim 1, characterized in that: The power outage time preset module uses an STM32F103C8T6 as the MCU. The MCU's internal real-time clock RTC is used to set the preset time in years, months, days, hours, minutes, and seconds, and the settings are displayed on the LCD connected to the MCU. The external small relay KA1 is used for mode switching. The mode switching is set to occur during the elevator's idle time. The modes are divided into normal operation mode and timed maintenance mode. The power-off time preset module MCU's level signal powers the small relay KA1 through the optocoupler.

3. The elevator emergency power supply timed automatic maintenance device according to claim 1, characterized in that: When the maintenance timer expires, the maintenance control module simulates a power outage scenario. When pin 32 PA11 of the main control chip outputs a high level, the optocoupler energizes the small relay KA1, which, together with the timed maintenance contactor KM, automatically triggers to cut off the mains power and start the emergency power supply. The top floor button inside the elevator car is then linked with the small relay KA2 to perform automatic operation.

4. The elevator emergency power supply timed automatic maintenance device according to claim 1, characterized in that: When the maintenance timer stored in the power outage timer preset module expires and the ultrasonic obstacle avoidance sensor detects that no one is in the car, the power outage timer preset module's level signal energizes the miniature relay KA1. In conjunction with the automatic triggering action of the timed maintenance contactor KM, the elevator's mains power supply is cut off via the machine room's main power switch to activate the elevator's emergency power supply. At the same time, the miniature relay KA2 controls the internal wiring of the elevator car's control panel to move the car to the preset floor for maintenance work.

5. The elevator emergency power supply timed automatic maintenance device according to claim 4, characterized in that: After the power outage time preset module cuts off the mains power supply to the elevator via the main power switch in the machine room to activate the elevator's emergency power supply, the small relay KA2 controls the internal wiring of the elevator car control panel to move the car to the preset floor for maintenance work. This is achieved by short-circuiting the internal wiring contacts of the elevator car control panel to simulate the triggering of the floor buttons on the elevator car control panel.

6. The elevator emergency power supply timed automatic maintenance device according to claim 1, characterized in that: The emergency leveling device is an elevator power failure re-leveling device with a built-in emergency power supply, which uses multiple sets of lead-acid batteries as energy storage devices. The automatic maintenance device also includes a battery parameter acquisition module for collecting data on the voltage, temperature, and total charging and discharging current of each unit of the emergency power lead-acid battery.

7. The elevator emergency power supply timed automatic maintenance device according to claim 6, characterized in that: The battery parameter acquisition module acquires the voltage of each cell of the emergency power lead-acid battery through a voltage acquisition circuit containing a resistor voltage divider circuit and an LTC248 multiplexing chip.

8. The elevator emergency power supply timed automatic maintenance device according to claim 6, characterized in that: The battery parameter acquisition module collects the temperature of each cell of the emergency power lead-acid battery through a cell temperature acquisition board attached to the surface of the battery. The cell temperature acquisition board is equipped with a temperature sensor LM35.

9. The elevator emergency power supply timed automatic maintenance device according to claim 6, characterized in that: The battery parameter acquisition module uses the Hall effect current sensor ACS758 to acquire the total current signal of the emergency power supply charging and discharging circuit.

10. The elevator emergency power supply timed automatic maintenance device according to claim 6, characterized in that: The emergency leveling device also includes a network communication module for accessing an Internet of Things (IoT) platform.

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