CN116374765A

CN116374765A - Elevator door state monitoring system

Info

Publication number: CN116374765A
Application number: CN202310390012.9A
Authority: CN
Inventors: 郭贝; 郭涛; 李欣朔; 陈洁
Original assignee: Zibo Dongsheng Elevator Engineering Co ltd
Current assignee: Zibo Dongsheng Elevator Engineering Co ltd
Priority date: 2023-04-07
Filing date: 2023-04-07
Publication date: 2023-07-04

Abstract

The invention discloses an elevator door state monitoring system, which belongs to the technical field of elevator monitoring, and comprises a data collector and a master controller which is in communication connection with the data collector through a CAN bus, wherein: the data acquisition device comprises a first microcontroller, wherein the first microcontroller is connected with a door switch state acquisition circuit through an AD conversion circuit, and is also connected with a door leaf state acquisition circuit, a floor coding circuit, a first audible and visual alarm circuit and a first CAN bus communication circuit; the master controller comprises a second microcontroller which is used for being connected with an elevator master control board, and the second microcontroller is connected with a serial port screen, a second audible and visual alarm circuit and a second CAN bus communication circuit. The invention realizes the real-time monitoring of the state of the elevator door, can find the fault type and the fault floor of the door in time, effectively solves the problem of the failure of the door opening and closing function caused by human factors, and greatly improves the efficiency of personnel in checking the door fault.

Description

Elevator door state monitoring system

Technical Field

The invention relates to the technical field of elevator monitoring, in particular to an elevator door state monitoring system.

Background

With the rapid development of urban construction and rapid promotion of town, an elevator becomes an indispensable vertical transportation vehicle in daily life of people, and the safety and reliability of the elevator are more and more paid attention to and paid attention to. The reliability of an electrical safety device (hereinafter referred to as a "door switch") that confirms that a door is in a locked and closed state is an effective measure for avoiding the occurrence of personnel falling, shearing and crushing accidents. However, door switch failure has been the high incidence of elevator accidents. According to the data issued by the accident investigation and processing center of special equipment of the national market supervision administration, during 2002-2016, 64 accidents caused by the faults of the door lock related to traction and forced driving of the elevator occur altogether, wherein 50 elevator accidents caused by the failure of an electric safety device for verifying the closing of the door take over 50, account for 78.13% of the faults of the door lock, and are the first place of the total accident number of the elevator. The main causes of failure of the elevator door switch are: (1) The elevator door is frequently opened and closed, and the door is manually opened and closed in order to reduce the door lock failure; (2) The insulating property of the signal wire of the door switch is reduced or damaged, and the hoistway environment where the door switch is positioned is moist, so that the door switch is short-circuited. Once the door switch is in the artificial bypass and short circuit state, the control system can not normally judge the switch state of the elevator door, and elevator accidents can easily occur.

The main types of faults of elevator door switches are: open circuit, short circuit, and artificial bypass faults. In order to troubleshoot the faults, a door loop is usually separated from a control system, door loop detection signals on the control system are manually short-circuited, and fault points are troubleshooted layer by layer. In order to avoid accidents caused by unsafe factors of people, a new national standard of elevator manufacture and installation safety Specification part 1 implemented by 2022, 7 and 1 is: passenger and freight elevators have increased the need for landing door and car door bypass devices, preventing normal operation of the elevator when the door contacts fail, but are not monitored for door open conditions when the bypass function is used for service operation and for short conditions of a single contact checking the landing door closed position. Thus, omnibearing monitoring of the status of the elevator door is important.

Disclosure of Invention

The invention aims to provide an elevator door state monitoring system which can monitor various states of a door in real time and accurately position a floor where the door fails.

In order to solve the technical problems, the invention provides the following technical scheme:

The utility model provides an elevator door state monitoring system, includes data acquisition unit and with the total accuse ware that data acquisition unit passes through CAN bus communication and is connected, wherein:

the data acquisition device comprises a first microcontroller, wherein the first microcontroller is connected with a door switch state acquisition circuit through an AD conversion circuit, and is also connected with a door leaf state acquisition circuit, a floor coding circuit, a first audible and visual alarm circuit and a first CAN bus communication circuit;

the master controller comprises a second microcontroller which is used for being connected with an elevator master control board, and the second microcontroller is connected with a serial port screen, a second audible and visual alarm circuit and a second CAN bus communication circuit.

The invention has the following beneficial effects:

the elevator door state monitoring system realizes the real-time monitoring of the elevator door state, can timely find the fault type and the fault floor of the door by collecting the real-time data of the door switching voltage and the current and comparing and analyzing the parameters of the elevator main controller, effectively solves the problem of the failure of the door switching function caused by human factors, and greatly improves the efficiency of personnel checking the door fault.

Drawings

Fig. 1 is a schematic diagram of the overall architecture of an elevator door condition monitoring system of the present invention;

FIG. 2 is a schematic diagram of the power supply circuit of the data acquisition device of FIG. 1, wherein (a) is a 5V power supply circuit diagram and (b) is a 3.3V power supply circuit diagram;

FIG. 3 is a schematic diagram of the door switch state acquisition circuit of FIG. 1;

fig. 4 is a schematic diagram of the AD conversion circuit in fig. 1;

FIG. 5 is a schematic diagram of the door leaf status acquisition circuit of FIG. 1;

FIG. 6 is a schematic diagram of the floor encoder circuit of FIG. 1;

FIG. 7 is a schematic diagram of an audible and visual alarm circuit of the data acquisition unit of FIG. 1;

FIG. 8 is a schematic diagram of a microcontroller circuit of the data acquisition device of FIG. 1;

FIG. 9 is a schematic diagram of a CAN bus communication circuit of the data collector of FIG. 1;

FIG. 10 is a schematic diagram of the power circuit of the 4G module of FIG. 1;

FIG. 11 is a schematic diagram of the 4G module circuit of FIG. 1;

FIG. 12 is a schematic diagram of an RS485 bus circuit of the master controller of FIG. 1;

FIG. 13 is a schematic diagram of an RS232 serial circuit of the master controller of FIG. 1;

FIG. 14 is a schematic diagram of a microcontroller circuit of the master controller of FIG. 1;

fig. 15 is a schematic workflow diagram of the elevator door condition monitoring system of fig. 1.

Detailed Description

In order to make the technical problems, technical solutions and advantages to be solved more apparent, the following detailed description will be given with reference to the accompanying drawings and specific embodiments.

The invention provides an elevator door state monitoring system, which is introduced one by one from three aspects of system overall architecture design, hardware design and software design.

1 System overall architecture design

As shown in fig. 1, the elevator door status monitoring system of the present invention includes a data collector 1 and a master controller 2 communicatively connected to the data collector 1 through a CAN (controller area network) bus, wherein:

the data acquisition device 1 comprises a first microcontroller 11, wherein the first microcontroller 11 is connected with a door switch state acquisition circuit 13 through an AD (digital-to-analog) conversion circuit 12, and the first microcontroller 11 is also connected with a door leaf state acquisition circuit 14, a floor coding circuit 15, a first audible and visual alarm circuit 16 and a first CAN bus communication circuit (not shown in fig. 1);

the master controller 2 comprises a second microcontroller 21, the second microcontroller 21 is used for an elevator master control board 22, and the second microcontroller 21 is connected with a serial port screen 23, a second audible alarm circuit 24 and a second CAN bus communication circuit (not shown in fig. 1).

When the elevator door monitoring system works, the data collector 1 is used for collecting the opening and closing states of the elevator door, analyzing and judging whether the current elevator door has faults or not through information collected by the sensors (namely, information collected by the door opening and closing state collecting circuit 13, the door leaf state collecting circuit 14 and the floor coding circuit 15), and communicating with the main controller 2 through the CAN bus; the master controller 2 is used for comparing the collected data information with the data of the elevator master control board 22 to determine whether the elevator door state is in a normal state, and when the data abnormality is monitored, an alarm is given, and a responsible person can be notified to repair.

2. Hardware design

2.1 Design of data collector

The data acquisition device 1 is composed of a power supply circuit, a door switch state acquisition circuit 13, an AD conversion circuit 12, a door leaf state acquisition circuit 14, a floor coding circuit 15, a first audible and visual alarm circuit 16, a first CAN bus communication circuit, a first microcontroller 11 and the like. The door switch state acquisition circuit 13 transmits the acquired door state signal to the first microcontroller 11 through the AD conversion circuit 12, performs data processing with the door leaf state signal and the floor coding signal acquired by the first microcontroller 11, performs audible and visual alarm when abnormality is monitored, and simultaneously transmits data information to the master controller 2 through CAN bus communication.

2.1.1 Power supply Circuit

The power supply provided by the elevator is 12V generally, and the power supply needs to be converted because of different voltages required by each chip, and the whole system needs three working power supplies of 12V, 5V and 3.3V. Accordingly, the data collector 1 may further include a power supply circuit including a 5V power supply circuit for supplying power to the first CAN bus communication circuit and the AD conversion circuit 12 and a 3.3V power supply circuit for supplying power to the first microcontroller 11, as shown in fig. 2, wherein:

The 5V power supply circuit comprises a first voltage stabilizer U6, wherein the input end Vin of the first voltage stabilizer U6 is connected with a 12V power supply, the output end Vout is used for outputting the 5V power supply, the grounding end GND is grounded, and the input end Vin and the output end Vout of the first voltage stabilizer U6 are grounded through filter capacitors C12-15;

the 3.3V power supply circuit comprises a second voltage stabilizer U7, wherein the input end Vin of the second voltage stabilizer U7 is connected with a 5V power supply, the output end Vout is used for outputting the 3.3V power supply, the grounding end GND is grounded, and the input end Vin and the output end Vout of the second voltage stabilizer U7 are grounded through filter capacitors C21-24.

In fig. 2 (a) is a power supply voltage-reducing circuit diagram from 12V to 5V, and provides power for the CAN bus chip and the AD conversion chip, and the AD conversion chip needs to be powered by the 5V power supply, so that a corresponding power supply voltage-reducing circuit needs to be designed; the 12V voltage is filtered and then input into the Vin end of the first voltage stabilizer U6, and the output voltage is filtered by a capacitor to obtain a stable 5V power supply.

The U6 first voltage stabilizer can specifically adopt a 78M05 chip, the 78M05 chip is a three-terminal voltage stabilizing chip, the 1 pin is 12V power input, the C12 and the C13 are input power filter capacitors, the 2 pin is connected with GND (ground), the 3 pin outputs 5V voltage, the C14 and the C15 are output 5V power filter capacitors, and the stable power supply of the output 5V power supply is ensured.

In fig. 2 (b), a circuit diagram of a power supply voltage step-down circuit for converting 5V to 3.3V is shown, and a corresponding power supply voltage step-down circuit is required to be designed because the first microcontroller 11 needs 3.3V power supply to supply power to the first microcontroller 11; the 5V voltage is filtered and then is input into the Vin end of the second voltage stabilizer U7, and the Vout end outputs the voltage and is filtered by a capacitor to obtain a stable 3.3V power supply.

The second voltage stabilizer U7 can specifically adopt an AMS1117-3.3 chip, the 3 pin is 5V power input, the C21 and the C23 are 5V power filter capacitors, the 2 pin is 3.3V power output, the C24 and the C22 are 3.3V output power filter capacitors, the output end Vout is grounded through a resistor R24 and a light-emitting diode D4, the D4 is a power indicator lamp, the power indicator lamp is powered on, the power indicator lamp represents that the power works normally, and the R24 is a D4 current-limiting voltage-dividing resistor.

2.1.2 door switch state acquisition circuit

As shown in fig. 3, the door switch state acquisition circuit 13 may include a current sensor U1, a voltage transformer T1, and an operational amplifier U4, wherein:

the current inflow end IP+ to be detected and the current outflow end IP-to be detected of the current sensor U1 are respectively connected with two ends of the monitored gate switch P1, the power supply end VCC is connected with a 5V power supply, the grounding end GND is grounded, and the output end VIOUT is input into the AD conversion circuit 12 after RC filtering (R1 and C3) (see the sign AIN0 in the figure);

The two ends of the primary winding of the voltage transformer T1 are respectively connected with the two ends of the monitored gate switch P1, one of the two ends of the secondary winding is connected to the other end through a diode D2 and a resistor R9 and is grounded at the same time, the two ends of the resistor R9 are connected with a filter capacitor C6 in parallel, and a connecting point between the diode D2 and the resistor R9 is connected to the non-inverting input end of the operational amplifier U4 through a resistor R5;

the positive power supply of the operational amplifier U4 is connected with a 5V power supply, the negative power supply is connected with the ground after passing through a resistor R13, the output end is connected with the reverse input end of the operational amplifier U4 after passing through a resistor R12, and the output end is input into an AD conversion circuit 12 after being subjected to RC filtering (R7 and C8) (see the sign AIN1 in the figure).

The gate switch state acquisition circuit 13 is composed of a current sensor U1 (specifically, ACS712 chip may be adopted) and a voltage transformer T1 (specifically ZMPT107 may be adopted) and is used for respectively acquiring and monitoring current and voltage information of the gate switch. The ACS712 is internally provided with a low-bias linear Hall sensor circuit, can output voltage proportional to the monitored current, has the bandwidth of 50kHz, the maximum total output error of 4 percent, and high output sensitivity (66-185 mV/A), has the characteristics of low noise, quick response and high insulation voltage, and can be used for overcurrent fault protection.

P1 is a door lock switch binding post, U1 is a current acquisition chip, and a Hall current chip of ACS712 (specifically ACS712 ELCTR-05B-T) is adopted to detect the current on the switch P1, so that whether the door lock switch is short-circuited to ground or not is monitored. The current of the monitored gate switch is input through the IP+ of the ASC712 sensor, the IP-output is carried out, the passing current generates a magnetic field in the sensor, an analog voltage which is in linear relation with the monitored current is induced by the Hall element, the analog voltage is output by the VIOUT, and the analog voltage is input into the AD conversion circuit after RC filtering, so that the state monitoring of the ground short circuit of the gate switch is realized.

The ACS712 chip has three different versions of 5A, 20A and 30A, the design can adopt the 5A version, because the short circuit is only a moment, the acquisition sensitivity is improved by adopting a low range, the Hall current chip can measure alternating current or direct current, when detecting that the current is 0, the voltage of the 7 pins outputs 2.5V, when detecting that the forward current, the voltage of the 7 pins outputs between 2.5 and 5V, when detecting that the reverse current, the voltage of the 7 pins changes between 0 and 2.5V, and the analog quantity of the change is sent to the high-precision ADC conversion chip, thereby realizing the detection of the short circuit state of the door lock.

The voltage transformer is responsible for detecting whether voltage exists on the P1 switch, so that whether the switch state is on or off is judged. After the monitored gate switching voltage is rectified by a voltage transformer ZMPT107 and a fast switching tube D2 (specifically can be 1N 148), the voltage at two ends of a current-to-voltage resistor R9 is transmitted to an in-phase operational amplifier U4 (specifically can be AD 8605), and the analog voltage with the amplification factor of 1+R12/R13 is input to an AD conversion chip for data conversion after RC filtering, so that the opening and closing of the gate switching state are monitored.

2.1.3AD conversion circuit

As shown in fig. 4, the AD conversion circuit 12 may include an AD conversion chip U2 and a voltage reference chip U3, in which:

the analog power supply end AVDD of the AD conversion chip U2 is connected with a 5V power supply, the analog grounding end AGND and the negative reference input end VREFN are grounded, the analog input ends AIN0 and AIN1 respectively receive output signals of the current sensor U1 and the operational amplifier U4, an SPI interface (comprising a clock signal line SCLK, a data input line DIN, a data output line DOUT and a chip selection line CS), a data effective signal end DRDY, a synchronizing end SYNC and a RESET end RESET are connected to the first microcontroller 11, a clock circuit Y1 is connected between the two crystal oscillator connecting ends XTAL1 and XTAL2, the two crystal oscillator connecting ends XTAL1 and XTAL2 are grounded after being respectively connected with a 3.3V power supply through capacitors C10 and C11, the digital power supply end DVDD is grounded;

The input end VIN of the voltage reference chip U3 is connected with a 5V power supply, the output end VOUT is connected with the positive reference input end VREFP of the AD conversion chip U2, and the ground end GND is grounded.

The AD conversion circuit 12 is mainly responsible for converting the current and voltage data of the acquisition gate switch into digital values, and inputs the digital values to the first microcontroller 11 through the SPI interface for data processing. In order to improve the data acquisition accuracy, a REF2930 voltage reference chip is adopted. Y1 is a clock circuit of the AD conversion chip, and in order to obtain a stable clock frequency, a C10 crystal oscillator and a C11 crystal oscillator are used for capacitive filtering (ensuring the stable clock frequency), and a 7.68MHz crystal oscillator is selected.

The AD conversion chip U2 is mainly responsible for collecting current data and voltage data of a door lock switch, and can adopt an ADS1256 chip produced by TI company, which is a micro-power consumption, high-precision and 8-channel 24-bit delta-sigma analog-digital converter, has the characteristics of low nonlinearity of +/-0.001 percent, no noise level of 23bit, data sampling speed of 30ksps and the like, and adopts a four-wire SPI communication mode (clock signal line SCLK, data input line DIN, data output line DOUT and chip selection line CS) to connect with pins of the single chip microcomputer PB9-PB 15. The SPI is a serial digital interface that can communicate with the first microcontroller 11, and the data valid signal DRDY is used to indicate whether the conversion of data is complete. SYNC and RESET are the synchronous input and RESET of data, respectively.

2.1.4 door leaf state acquisition, floor coding and audible and visual alarm circuit

As shown in fig. 5, the door leaf status collection circuit 14 may include a photo sensor P2, where a positive power supply electrode (i.e. a brown wire pin in the drawing) of the photo sensor P2 is connected to a 5V power supply, a negative power supply electrode (i.e. a blue wire pin in the drawing) is grounded, and a switching signal output end (i.e. a black wire pin in the drawing) is connected to one path of the power supply electrode through a resistor R16 and then to the other path of the power supply electrode through a zener diode D3, and the other path of the power supply electrode is connected to the first microcontroller 11 (see reference numeral PB5 in the drawing).

The door leaf state acquisition circuit 14 acquires the opening and closing state of the elevator door leaf by the photoelectric sensor P2, and directly inputs the acquired digital signal to the first microcontroller 11 to judge the opening and closing state of the door. In the photoelectric sensor P2, two

pins

1 and 3 are power supply pins, a pin 2 is a signal output pin, a pin R16 is an output current-limiting diode, a pin D3 is a voltage-stabilizing diode, the changed digital signal is sent to a PB5 pin of the first microcontroller 11, and the first microcontroller 11 can know whether a door leaf switch is opened or not by reading the change of the high level and the low level of the PB5 pin.

As shown in fig. 6, the floor coding circuit 15 may include a 6-bit coding switch S1, where one end of the 6-bit coding switch S1 is grounded, one end of the other end is connected to a 3.3V power supply through resistors R14, R15, R17, R18, R19, R20, respectively, and the other end is connected to the first microcontroller 11, respectively.

In order to facilitate the controller to monitor the fault location of the landing switch, the floor coding circuit 15 uses a 6-bit coding switch S1, can set 64 floor codes, sets unique ID information for each floor, and inputs the code signal into the first microcontroller 11.

S1 is a 6-bit coding switch, 64 different coding states CAN be generated altogether, R14, R15, R17, R18, R19 and R20 are pull-up resistors, the coding switch is turned on, the corresponding pin of the first microcontroller 11 is low level, otherwise, the corresponding pin is pulled up by the pull-up resistors, the first microcontroller 11 reads the high-low level change state of the pins PA3-PA8, and when the CAN bus communication sends data, fault information and address information are sent to a host (a master controller 2) together, and the host CAN know which layer has faults.

As shown in fig. 7, the first audible and visual alarm circuit 16 may include an audible alarm sub-circuit and a visual alarm sub-circuit, wherein:

the acoustic alarm sub-circuit comprises a triode Q1, wherein the base electrode of the triode Q1 is connected to the first microcontroller 11 (see the reference sign PB0 in the figure) through a resistor R28, the emitter electrode is connected with a 3.3V power supply, and the collector electrode is grounded through a buzzer LS 1;

the light alarm sub-circuit comprises a light emitting diode D5, the anode of the light emitting diode D5 is connected to a 3.3V power supply via a resistor R26, and the cathode is connected to the first microcontroller 11 (see reference sign PB1 in the figure).

The first audible and visual alarm circuit 16 performs audible and visual alarm for the failure state of the door, and when abnormality is detected, it gives out audible and visual alarm to give a warning. In specific implementation, when the first microcontroller 11 compares the data detected by the door lock switch with the host data, if the first microcontroller 11 finds that the first microcontroller is manually opened, the PB0 PB1 of the first microcontroller 11 outputs a low level, the buzzer alarms, and the D5 is on for audible and visual reminding.

2.1.5 first microcontroller

As shown in fig. 8, the first microcontroller 11 may employ an STM32F103C8T6 (hereinafter, STM 32) chip, in which:

a clock circuit X1 for providing 8MHz clock signal is connected between the two crystal oscillator connection terminals OSC_IN and OSC_OUT of the first microcontroller 11;

the reset terminal NRST of the first microcontroller 11 is connected to a reset circuit, the reset circuit includes a resistor R25 and a capacitor C25, the 3.3V power supply is grounded through the resistor R25 and the capacitor C25, and a connection point between the resistor R25 and the capacitor C25 is connected to the reset terminal NRST of the first microcontroller 11.

The design can adopt STM32F103C8T6 microcontroller of ST company as control chip of data collector 1 and master controller 2, which is a 32-bit microcontroller based on ARM Cortex-M3 kernel, the working frequency is 72MHz, high-speed memory is built in, abundant enhanced I/O ports and peripheral equipment connected to two APB (advanced peripheral bus) buses.

The STM32 microcontroller obtains elevator door state information by reading data information of the AD converter and the door leaf sensor and performing data processing and analysis, judges whether a door switch has a fault, and sends out an audible and visual alarm signal when a fault signal is monitored.

The clock circuit X1 provides an 8MHz clock signal to STM32, and C19 and C20 stabilize the clock frequency. R25 and C25 are STM32 singlechip reset circuits, and the power-on utilizes the principle of capacitor charge and discharge to reset automatically. R27 is a pull-down resistor of the STM32 singlechip BOOT0, and the STM32 singlechip is normally started. And C26, C27, C28 and C29 are STM32 singlechip power supply filter capacitors, so that the power supply stability of the STM32 singlechip power supply is ensured. And P3 is an SWD interface for realizing reading and writing of program data, and the STLINK writer is connected with a computer to realize online debugging and programming.

2.1.6CAN bus communication circuit

As shown in fig. 9, the first CAN bus communication circuit may include a CAN transceiver chip U5 and a CAN bus interface P4, wherein:

the data transmitting terminal TXD and the data receiving terminal RXD of the CAN transceiver chip U5 are respectively connected to the first microcontroller 11 (see reference numerals a12_cantx and a11_cantx in the figure), the power terminal VCC is connected to a 5V power supply, and the ground terminal GND is grounded;

One path of high-level CAN bus connection end CANH of the CAN transceiver chip U5 is connected to the CAN bus interface P4 through a resistor R21, the other path is grounded through a capacitor C17, one path of low-level CAN bus connection end CANL is connected to the CAN bus interface P4 through a resistor R23, and the other path is grounded through a capacitor C16;

the CAN bus interface P4 is connected with a port of the high-level CAN bus connecting end CANH and a port of the CAN bus interface P4 is connected with the low-level CAN bus connecting end CANL, and a matching resistor R22 is connected between the two ports.

The data acquired by the whole data acquisition device 1 are communicated with the master controller 2 through the CAN bus, the door leaf switch and door lock switch state is sent to the master controller 2 through the CAN bus, the master controller 2 is compared with the elevator main board data, whether the elevator reaches the normal door switch state of the appointed floor or the abnormal state is caused artificially is judged, and accordingly an alarm is triggered.

In the first CAN bus communication circuit, the CAN transceiver chip U5 may specifically use a TJA1050 chip as a CAN bus communication transceiver, where the highest transmission rate is 1Mb/s, and the first CAN bus communication circuit has a mute mode and a higher anti-electromagnetic interference capability, and may convert an output signal CANTX into a differential signal pair to send to a bus, or convert a differential signal pair on the CAN bus into cantrx. The two

pins

1 and 4 are connected with serial ports A11 and A12 of the STM32F103C8T6 singlechip, the serial ports are converted into CAN data through a CAN bus chip, C16 and C17 are filter capacitors, high-frequency interference of a bus is filtered, R22 (120 ohms) is an impedance matching resistor used for impedance matching of the bus and eliminating signal reflection, the two

pins

2 and 3 of the P4 port are connected, the two

pins

1 and 4 are power supply pins, and the P4 is powered by a direct current 12V power supply. The whole CAN bus communication circuit realizes data communication between data information acquired by the data acquisition device and STM 32.

2.2 design of master controller

The master controller 2 is composed of a power circuit, a second audible alarm circuit 24, an RS485 and CAN bus communication circuit, a 4G module circuit, an RS232 serial port screen circuit, a second microcontroller 21 and the like, wherein the design of the power circuit, the second audible alarm circuit 24 and the second CAN bus communication circuit of the master controller 2 is consistent with the design of the 2.1 part data acquisition unit, and the details are not repeated here. The 5V power supply supplies power to the CAN bus chip and other peripheral elements; the second CAN bus communication circuit is responsible for collecting the data collected by the elevator layer data collector 1.

2.2.1 4G module circuit

The second microcontroller 21 may further be connected with a 4G module circuit 25,4G module circuit 25, which may include a 4G communication module and a 4G module power circuit for supplying power to the 4G communication module, as shown in fig. 10, where the 4G module power circuit includes a DC-DC switching power supply conversion chip U7, and in which:

the power end VIN of the DC-DC switching power supply conversion chip U7 is connected with a 12V power supply, the ground end GND is grounded, and filter capacitors C27 and C28 are connected in series between the power end VIN and the ground end GND;

the boost capacitor high-side FET (Field Effect Transistor ) gate drive connection end BOOT of the DC-DC switching power supply conversion chip U7 is used as a battery anode VBAT for supplying power to the 4G communication module after passing through a capacitor C25 and an inductor L1, one path of connection point between the capacitor C25 and the inductor L1 is connected with the feedback voltage regulation connection end PH of the DC-DC switching power supply conversion chip U7, and the other path is grounded through a freewheeling diode D6;

One path of the battery anode VBAT is grounded through a first sampling resistor R26 and a second sampling resistor R28, the other path of the battery anode VBAT is grounded through filter capacitors C29 and C30, and a connection point between the first sampling resistor R26 and the second sampling resistor R28 is connected with a high-bias power MOSFET source connection end VSENSE of the DC-DC switching power supply conversion chip U7.

The 4G module circuit 25 may specifically adopt an Air724UG communication module, and its voltage input range is 3.3-4.3V, because the LTE radio frequency works with a continuous working current of about 700mA, the power supply must be able to provide enough current, so a DC-DC switching power supply conversion chip U7 (specifically may adopt a TPS5430 chip) is selected to form a step-down circuit, and the chip has the characteristics of high conversion efficiency, adjustable output voltage, and large output current.

The 4G module power supply circuit is a 12V-to-4.2V DC-DC voltage reduction circuit, and because the Air724UG 4G communication module needs direct current 4.2V power supply for power supply, the voltage needs to be reduced further. U7 TPS5430 is DC-DC step-down chip, 7 foot is 12V power input, C27, C28 are 12V power input filter capacitance, D6 is the freewheel diode, L1 is energy storage inductance, freewheel diode D6 and energy storage inductance L1's effect is the sudden change that prevents voltage current and protects the circuit, R26, R28 are output sample feedback resistance, output sample resistance R26 and R28 decide the size of output voltage, C29, C30 are output power filter capacitance, guarantee output power supply stability.

Air724UG is a whole network 4G module of ultra-small encapsulation LTE Cat.1bis, which is deduced by the universe communication, can adapt to different operators and products, adopts a ultraviolet sharp UIS8910 platform, and supports the LTE 3GPP rel.13 technology. The module is internally provided with rich network protocols, integrates a plurality of industry standard interfaces, supports various driving and software functions, and supports various development modes, such as AT and Lua secondary development.

As shown in fig. 11, a low ESR tantalum capacitor C4 and 2 filter capacitors C1 and C2 may be connected in series between the power supply end VBAT and the ground end GND of the 4G communication module, so as to prevent the power supply voltage drop phenomenon generated on the VBAT power supply when the 4G communication module transmits radio frequency;

and/or, the on-off control pin PWRKEY of the 4G communication module may be connected to a start-up driving circuit, where the start-up driving circuit includes a triode Q1, one path of the base of the triode Q1 is connected to the second microcontroller 21 (see reference PA15 in the figure) through a resistor R1, the other path of the base of the triode is connected to the emitter of the triode Q1 through a resistor R3, the collector of the triode Q1 is connected to the on-off control pin PWRKEY of the 4G communication module, and the emitter is grounded, so that the on-off of the module is realized by controlling the pin PWRKEY by using the start-up driving circuit;

And/or, in order to increase ESD (electrostatic discharge) electrostatic protection in the SIM card circuit, an electrostatic protection device SMF05 can be arranged in the SIM card circuit of the 4G communication module, the 1 st pin of the electrostatic protection device SMF05 is suspended, the 2 nd pin is grounded, one path of the 3 rd pin is grounded after passing through a capacitor C23, the other path of the 3 rd pin is connected to the SIM card DATA end SIM_DATA of the 4G communication module through a resistor R25, the 4 th pin is connected with a clock pin CLK of the SIM card, the 5 th pin is connected with a DATA pin DAT of the SIM card, and the 6 th pin is connected with a reset pin RST of the SIM card;

and/or, in the SIM card circuit of the 4G communication module, a reset pin RST, a data pin DAT and a clock pin CLK of the SIM card are connected in series with resistors (R16, R22 and R18) for matching load impedance, and a parallel capacitor (C22, C20 and C21) for filtering high-frequency interference;

and/or, the serial port level of the data transmission TXD and the serial port level of the receiving RXD of the 4G module are 1.8V, and data communication with the level of the second microcontroller 21 is required to be performed, so that a level conversion circuit is required to be added, so that both the data transmission end uart1_txd and the data receiving end uart1_rxd of the 4G communication module can be provided with a level conversion circuit, the level conversion circuit comprises a triode Q2 and a schottky diode D4 (D4 is a schottky diode with low conduction voltage drop), the base electrode of the triode Q2 is connected with a 1.8V power supply through a resistor R9, the emitter is connected with the data transmission end uart1_txd, and the collector is connected with a 3.3V power supply through a resistor R10 and is simultaneously connected with the second microcontroller 21 (see the reference symbol PA10_rx 1); the data receiving terminal uart1_rxd is connected to a 1.8V power supply via a resistor R8 and is connected to the second microcontroller 21 via a schottky diode D4 (see reference numeral PA9 TX1 in the figure);

And/or, the antenna connection end lte_ant of the 4G communication module may be connected to the antenna through a pi-type circuit, where the pi-type circuit includes a series resistor R7, and two ends of the resistor are grounded through capacitors C10 and C11, respectively, and since the impedance of the radio frequency antenna connected to the module needs to be controlled to be 50Ω, in order to correct the deviation of the resistor, a pi-type circuit is added to perform impedance matching;

and/or, the network MODE output end net_mode of the 4G communication module may be connected with a network MODE indicating circuit, where the network MODE indicating circuit includes a light emitting diode LTE2 and a triode Q4, the base of the triode Q4 is connected to the network MODE output end net_mode via a resistor R20 and is connected to the emitter of the triode Q4 via a resistor R23, the collector is connected to the battery anode VBAT via a resistor R14 and the light emitting diode LTE2, the emitter is grounded, and the LET2 may be a 4G network MODE indicator lamp;

and/or, the network state output end net_status of the 4G communication module may be connected with a network state indicating circuit, where the network state indicating circuit includes a light emitting diode NET1 and a triode Q5, the base of the triode Q5 is connected to the network state output end net_status through a resistor R21 and is connected to the emitter of the triode Q5 through a resistor R24, the collector is connected to the battery anode VBAT through a resistor R15 and the light emitting diode NET1, the emitter is grounded, and NET1 is a network state indicating lamp.

Fig. 11 is a 4G communication module, and adopts an Air724UG module, and the singlechip uses serial ports PA9, PA10 and 4G module to communicate, and when the singlechip detects that the door lock door leaf is abnormal in opening and closing state, a short message can be sent to an elevator responsible person through the 4G module to remind the elevator of abnormality. CN1 is SIM card seat, and can be connected to network by inserting telephone card.

2.2.2RS485 bus circuit

The master controller 2 and the elevator master control board 22 can carry out data communication through an RS485 bus, an RS485 bus circuit and a 485 bus interface can be arranged between the second microcontroller 21 and the elevator master control board 22, and as shown in fig. 12, the RS485 bus circuit comprises a level conversion chip U2, wherein:

the receiver output end RO and the driver input end DI of the level conversion chip U2 are respectively connected to the data receiving end PA3 RX and the data transmitting end PA2 TX of the second microcontroller 21, and the receiver output enable control end RE and the driver output enable control end DE are both connected to the second microcontroller 21 (specifically may be the pin PA 4);

the power end VCC of the level conversion chip U2 is connected with a 3.3V power supply and is connected to an A port of the level conversion chip U2 through a resistor R4, wherein the A port is a port corresponding to the input of a non-inverting receiver and the output of a non-inverting driver;

the ground end GND of the level conversion chip U2 is grounded and is connected to the port B of the level conversion chip U2 through a resistor R6, and the port B is a port corresponding to the input of the inverting receiver and the output of the inverting driver;

One path of the port A of the level conversion chip U2 is grounded through a transient voltage suppression diode (Transient Voltage Suppressor, TVS) D1, and the other path is connected to a 485 bus interface P1 (3 rd pin in the figure);

one path of the port B of the level conversion chip U2 is grounded through a transient voltage suppression diode D3, and the other path is connected to a 485 bus interface P1 (a 2 nd pin in the figure);

a matching resistor R5 is also connected in series between the A port and the B port of the level conversion chip U2.

The RS485 bus circuit is in charge of communicating with the elevator main control board 22, and the transient voltage suppression diodes D1 and D3 are used for protecting a bus interface and avoiding damage to a transceiver caused by external interference; the resistor R5 is a terminal matching resistor, so that signal reflection is avoided, and the stability and reliability of communication are improved; the resistors R4 and R6 are used for preventing electromagnetic interference generated by suspending the input end and weakening interference of external current to the chip. The level conversion chip U2 may be an SP3485EEN chip, for converting the TTL level of the second microcontroller 21 into 485 level, and the DE and RE are used for controlling the 485 chip to send and receive data for enabling.

In the RS485 bus circuit, P1 is a 485 bus port, two

pins

1 and 4 are power supply pins, and two

pins

2 and 3 are 485 data pins A, B; the SP3485EEN chip is mainly responsible for converting the TTL serial port of the second microcontroller 21 into 485 data, the 1 pin and the 4 pin are connected with the PA2 pin and the PA3 pin of the second microcontroller 21, and the PA4 controls the 485 chip to send and receive data to enable.

2.2.3RS232 serial port communication circuit

In order to check the states of the door switches of the elevator in real time, an RS232 serial port screen of a general interface can be adopted, and a design circuit diagram is shown in fig. 13.

The RS232 serial port communication circuit is used for receiving the 232 serial port screen, and the 232 serial port belongs to a universal interface, so that the screen supporting the 232 serial port can be used without limitation of the model, the P5 is a 232 touch screen interface, the 1 pin and the 4 pin are power supply pins, and the 2 pin and the 3 pin are 232 data pins.

The level conversion chip U8 can specifically adopt SP3232EEN-L/TR, and is responsible for converting the PB10 and PB11 serial ports of the second microcontroller 21 into 232 levels, so as to realize conversion between STM32 serial port TTL levels and 232 levels. And C32, C33, C35 and C36 are charge pump capacitors in the 232 chip, and C31 is a power supply filter capacitor, so that the power supply stability of the 232 chip is ensured.

2.2.4 second microcontroller

Fig. 14 is a circuit of the second microcontroller 21 in the master controller 2, the data information collected by the data collector 1 is transmitted to the second microcontroller 21 of the master controller 2 through the CAN bus communication to perform data processing, when abnormal data is monitored, audible and visual alarm CAN be performed, fault information is sent to an elevator responsible person through the 4G module 25, state information of an elevator door switch is displayed on a 232 serial port screen in real time, and the data information CAN be communicated with the elevator master control board 22 through the RS485 bus communication to send out instruction signals, so that the elevator is prohibited from starting to run, and the safety of personnel and equipment is ensured.

Fig. 14 shows an STM32 single-chip microcomputer minimum system, which is composed of a clock circuit, a reset circuit and the like, wherein the clock circuit is composed of an X1, a C24 and a C26, the X1 provides 8Mhz clock signals for the single-chip microcomputer, and the C24 and the C26 stabilize clock frequencies.

R27 and C34 are STM32 singlechip reset circuits, and the power-on utilizes the principle of capacitor charge and discharge to reset automatically. R29 is a pull-down resistor of the STM32 singlechip BOOT0, and the STM32 singlechip is normally started.

And C37, C38, C39 and C40 are STM32 singlechip power supply filter capacitors, so that the power supply stability of the STM32 singlechip power supply is ensured. P4 is SWD interface, uses STLINK writer to connect computer, can realize online debugging, programming program.

3 software design

The program design of the system mainly comprises a data acquisition part, a data transmission part, a data processing part and a fault judgment alarm part 4. The data acquisition procedure is mainly completed by the first microcontroller 11 and the AD conversion circuit 12, the acquired data (including the door state data after AD conversion) is communicated with the first microcontroller 11 through an SPI interface, and the floor coding and door leaf digital quantity data are directly connected into the first microcontroller 11. The data acquired by the first microcontroller 11 in the data acquisition device 1 are transmitted to the second microcontroller 21 in the master controller 2 through the CAN bus, and then are respectively transmitted to the elevator master control board 22 and the 232 serial port screen 23 through the RS485 and the RS232 bus, the data are processed, the door state is judged by faults, and the alarm is given out in real time when the abnormal situation is monitored. The program flow may be as shown in fig. 15.

In summary, the elevator door state monitoring system realizes real-time monitoring of the elevator door state, and can timely find the fault type and the fault floor of the door by collecting the real-time data of the door switching voltage and the current and comparing and analyzing the parameters of the elevator main controller, thereby effectively solving the problem of failure of the door switching function caused by human factors and greatly improving the efficiency of personnel checking the door faults.

While the foregoing is directed to the preferred embodiments of the present invention, it will be appreciated by those skilled in the art that various modifications and adaptations can be made without departing from the principles of the present invention, and such modifications and adaptations are intended to be comprehended within the scope of the present invention.

Claims

1. The elevator door state monitoring system is characterized by comprising a data acquisition unit and a master controller which is connected with the data acquisition unit through CAN bus communication, wherein:

2. The elevator door status monitoring system of claim 1, wherein the data collector further comprises a power circuit comprising a 5V power circuit for powering the first CAN bus communication circuit and AD conversion circuit and a 3.3V power circuit for powering the first microcontroller, wherein:

the 5V power supply circuit comprises a first voltage stabilizer, wherein the input end of the first voltage stabilizer is connected with a 12V power supply, the output end of the first voltage stabilizer is used for outputting a 5V power supply, the grounding end is grounded, and the input end and the output end of the first voltage stabilizer are grounded through a filter capacitor;

the 3.3V power supply circuit comprises a second voltage stabilizer, wherein the input end of the second voltage stabilizer is connected with a 5V power supply, the output end of the second voltage stabilizer is used for outputting a 3.3V power supply, the grounding end is grounded, and the input end and the output end of the second voltage stabilizer are grounded through filter capacitors.

3. The elevator door status monitoring system of claim 1, wherein the door switch status acquisition circuit comprises a current sensor, a voltage transformer, and an operational amplifier, wherein:

The current inflow end and the current outflow end of the current sensor are respectively connected with two ends of the monitored gate switch, the power supply is connected with a 5V power supply, the ground is grounded, and the output end is input into the AD conversion circuit after RC filtering;

two ends of a primary winding of the voltage transformer are respectively connected with two ends of a monitored door switch, one of the two ends of the secondary winding is connected to the other end through a diode and a resistor and is grounded at the same time, two ends of the resistor are connected with a capacitor in parallel, and a connecting point between the diode and the resistor is connected to a non-inverting input end of the operational amplifier through the resistor;

the positive power supply of the operational amplifier is connected with a 5V power supply, the negative power supply is grounded, the inverting input end of the operational amplifier is grounded after passing through a resistor, the output end of the operational amplifier is connected with the inverting input end of the operational amplifier after passing through the resistor, and the output end of the operational amplifier is input into the AD conversion circuit after being filtered by RC.

4. The elevator door status monitoring system of claim 3, wherein the AD conversion circuit comprises an AD conversion chip and a voltage reference chip, wherein:

the analog power supply end of the AD conversion chip is connected with a 5V power supply, the analog grounding end and the negative reference input end are grounded, the analog input end respectively receives output signals of the current sensor and the operational amplifier, the SPI interface, the data effective signal end, the synchronous end and the reset end are all connected to the first microcontroller, a clock circuit is connected between the two crystal oscillator connecting ends, the two crystal oscillator connecting ends are respectively grounded after passing through a capacitor, the digital power supply end is connected with a 3.3V power supply, and the digital grounding end is grounded;

The input end of the voltage reference chip is connected with a 5V power supply, the output end of the voltage reference chip is connected with the positive reference input end of the AD conversion chip, and the ground is grounded.

5. The elevator door state monitoring system according to claim 1, wherein the door leaf state acquisition circuit comprises a photoelectric sensor, a power supply anode of the photoelectric sensor is connected with a 5V power supply, a power supply cathode is grounded, one path of a switch signal output end is grounded through a zener diode after passing through a resistor, and the other path of the switch signal output end is connected to the first microcontroller;

and/or the floor coding circuit comprises 6-bit coding switches, one ends of the 6-bit coding switches are grounded, one paths of the other ends of the 6-bit coding switches are respectively connected with a 3.3V power supply through resistors, and the other paths of the 6-bit coding switches are respectively connected to the first microcontroller;

and/or the first audible and visual alarm circuit comprises an audible alarm sub-circuit and an audible alarm sub-circuit, wherein the audible alarm sub-circuit comprises a triode, the base electrode of the triode is connected to the first microcontroller through a resistor, the emitter electrode of the triode is connected with a 3.3V power supply, and the collector electrode of the triode is grounded through a buzzer; the light alarm sub-circuit comprises a light emitting diode, wherein the anode of the light emitting diode is connected with a 3.3V power supply through a resistor, and the cathode of the light emitting diode is connected with the first microcontroller.

6. The elevator door status monitoring system of claim 1, wherein the first microcontroller employs an STM32F103C8T6 chip, wherein:

a clock circuit for providing 8MHz clock signals is connected between the two crystal oscillator connecting ends of the first microcontroller;

the reset end of the first microcontroller is connected with a reset circuit, the reset circuit comprises a resistor and a capacitor, a 3.3V power supply is grounded after passing through the resistor and the capacitor, and a connection point between the resistor and the capacitor is connected with the reset end of the first microcontroller.

7. The elevator door status monitoring system of claim 1, wherein the first CAN bus communication circuit comprises a CAN transceiver chip and a CAN bus interface, wherein:

the data transmitting end and the data receiving end of the CAN transceiver chip are respectively connected to the first microcontroller, the power supply end is connected with a 5V power supply, and the grounding end is grounded;

one path of high-level CAN bus connecting end of the CAN transceiver chip is connected to the CAN bus interface after passing through a resistor, the other path of high-level CAN bus connecting end is grounded through a capacitor, one path of low-level CAN bus connecting end is connected to the CAN bus interface after passing through a resistor, and the other path of low-level CAN bus connecting end is grounded through a capacitor;

the CAN bus interface is connected with the port connected with the high-level CAN bus connecting end and the port connected with the low-level CAN bus connecting end, and a matching resistor is connected between the two ports.

8. The elevator door status monitoring system of claim 1, wherein the second microcontroller is further connected with a 4G module circuit, the 4G module circuit comprising a 4G communication module and a 4G module power circuit powering the 4G communication module, the 4G module power circuit comprising a DC-DC switching power conversion chip, wherein:

the power end of the DC-DC switching power supply conversion chip is connected with a 12V power supply, the grounding end is grounded, and a filter capacitor is connected in series between the power end and the grounding end;

the boost capacitor high-side FET grid driving connection end of the DC-DC switching power supply conversion chip is used as a battery anode for supplying power to the 4G communication module after passing through a capacitor and an inductor, one path of connection point between the capacitor and the inductor is connected with the feedback voltage regulating connection end of the DC-DC switching power supply conversion chip, and the other path of connection point is grounded through a freewheeling diode;

one path of the battery anode is grounded through the first sampling resistor and the second sampling resistor, the other path of the battery anode is grounded through the filter capacitor, and a connection point between the first sampling resistor and the second sampling resistor is connected with a source connection end of a high-bias power MOSFET of the DC-DC switching power supply conversion chip.

9. The elevator door status monitoring system of claim 8, wherein a low ESR tantalum capacitor and 2 filter capacitors are connected in series between the power terminal and the ground terminal of the 4G communication module;

And/or the on-off control pin of the 4G communication module is connected with a start-up driving circuit, the start-up driving circuit comprises a triode, one path of the base electrode of the triode is connected to the second microcontroller through a resistor, the other path of the base electrode of the triode is connected to the emitting electrode of the triode through a resistor, the collecting electrode of the triode is connected with the on-off control pin of the 4G communication module, and the emitting electrode is grounded;

and/or, an electrostatic protection device SMF05 is arranged in the SIM card circuit of the 4G communication module, a 1 st pin of the electrostatic protection device SMF05 is suspended, a 2 nd pin is grounded, one path of a 3 rd pin is grounded after passing through a capacitor, the other path of the 3 rd pin is connected to the SIM card data end of the 4G communication module through a resistor, a 4 th pin is connected with a clock pin of the SIM card, a 5 th pin is connected with a data pin of the SIM card, and a 6 th pin is connected with a reset pin of the SIM card;

and/or, in the SIM card circuit of the 4G communication module, the reset pin, the data pin and the clock pin of the SIM card are connected in series with resistors for matching load impedance, and the parallel capacitor is used for filtering high-frequency interference;

and/or, the data transmitting end and the data receiving end of the 4G communication module are both provided with a level conversion circuit, the level conversion circuit comprises a triode and a Schottky diode, the base electrode of the triode is connected with a 1.8V power supply through a resistor, the emitter electrode of the triode is connected with the data transmitting end, and the collector electrode of the triode is connected with a 3.3V power supply through a resistor and is simultaneously connected to the second microcontroller; the data receiving end is connected with a 1.8V power supply through a resistor and is connected to the second microcontroller through the Schottky diode;

And/or the antenna connecting end of the 4G communication module is connected to the antenna through a pi-type circuit, the pi-type circuit comprises resistors connected in series, and two ends of the resistors are respectively grounded through capacitors;

and/or the network mode output end of the 4G communication module is connected with a network mode indicating circuit, the network mode indicating circuit comprises a light emitting diode and a triode, the base electrode of the triode is connected with the network mode output end through a resistor and is simultaneously connected with the emitting electrode of the triode through a resistor, the collector electrode is connected with the anode of the battery through the resistor and the light emitting diode, and the emitting electrode is grounded;

and/or the network state output end of the 4G communication module is connected with a network state indicating circuit, the network state indicating circuit comprises a light emitting diode and a triode, the base electrode of the triode is connected with the network state output end through a resistor and is connected with the emitting electrode of the triode through a resistor, the collector electrode is connected with the anode of the battery through the resistor and the light emitting diode, and the emitting electrode is grounded.

10. The elevator door status monitoring system of claim 1, wherein an RS485 bus circuit is provided between the second microcontroller and the elevator main control board, the RS485 bus circuit comprising a level shift chip and a 485 bus interface, wherein:

The receiver output end and the driver input end of the level conversion chip are respectively connected to the data receiving end and the data transmitting end of the second microcontroller, and the receiver output enabling control end and the driver output enabling control end are both connected to the second microcontroller;

the power end of the level conversion chip is connected with a 3.3V power supply and is connected to an A port of the level conversion chip through a resistor, and the A port is a port corresponding to the input of the non-inverting receiver and the output of the non-inverting driver;

the grounding terminal of the level conversion chip is connected to the B port of the level conversion chip through a resistor, and the B port is a port corresponding to the input of the inverting receiver and the output of the inverting driver;

one path of an A port of the level conversion chip is grounded through a transient voltage suppression diode, and the other path of the A port of the level conversion chip is connected to the 485 bus interface;

one path of the port B of the level conversion chip is grounded through a transient voltage suppression diode, and the other path of the port B of the level conversion chip is connected to the 485 bus interface;

and a matching resistor is also connected in series between the A port and the B port of the level conversion chip.