Automatic subway fare gate based on emergency signal status detection

Abstract

This utility model relates to an automatic subway ticket gate based on emergency signal status detection, which includes an electrically connected status detection system circuit and an automatic ticket gate unit load circuit; the status detection system circuit includes an MCU and peripheral circuits electrically connected to the MCU; the peripheral circuits include an input detection circuit, a current detection amplification circuit, a backup power supply control circuit, a status indication circuit, and a current detection resistor electrically connected to the MCU; the MCU has an ADC pin and a GPIO pin; this utility model is reasonably designed, compact in structure, and easy to use.

Description

Technical Field

[0001] This utility model relates to an automatic ticket gate for subways based on emergency signal status detection, and is applied to the automatic ticket gate of subway AFC (Automatic Fare Collection) system. Background Technology

[0002] Currently, there is no status detection system designed for emergency signals of automatic ticket gates. The status of automatic ticket gates can only be confirmed through manual inspection or by reporting problems found on-site. Manual inspection is labor-intensive, requiring testing of every single automatic ticket gate, which is inefficient. When on-site staff discover a malfunction in an automatic ticket gate during use and report it, maintenance personnel need to investigate the cause of the malfunction on-site before repairs can be carried out, which causes inconvenience to normal passage.

[0003] To address the above shortcomings, a system for detecting open-circuit and short-circuit conditions of emergency signals on automatic ticket gates was designed. This system can confirm the current status of the automatic ticket gate by monitoring the status of its emergency signal interface circuit in real time, significantly reducing the frequency of manual inspections, saving costs, and enabling timely location of malfunctioning automatic ticket gates to identify the cause of the malfunction, thus improving the maintenance efficiency of automatic ticket gates in abnormal states.

[0004] The system also incorporates an input detection circuit and a backup power control circuit, which can detect the status of the external input voltage and determine whether the backup power supply needs to be activated. If the external input voltage is detected to be disconnected, the MCU activates the backup power supply through the backup power control circuit, thereby ensuring the stable operation of the system. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide an automatic ticket gate for subways based on emergency signal status detection.

[0006] To solve the above problems, the technical solution adopted by this utility model is as follows:

[0007] A subway automatic ticket gate based on emergency signal status detection includes an electrically connected status detection system circuit and an automatic ticket gate unit load circuit.

[0008] The condition detection system circuit includes an MCU and peripheral circuits electrically connected to the MCU;

[0009] The peripheral circuitry includes an input detection circuit, a current detection amplifier circuit, a backup power control circuit, a status indicator circuit, and a current detection resistor, all of which are electrically connected to the MCU.

[0010] The MCU has ADC pins and GPIO pins;

[0011] The ADC pin is electrically connected to the current detection amplifier circuit.

[0012] The current detection amplifier circuit includes chip U1; in chip U1, pin 6 is connected to the ADC pin, pins 1 and 2 are grounded, pin 3 is connected to VCC1, and a bridge A consisting of resistors R2-4 and capacitor C1 is connected between pins 4 and 5; VCC3 is split into three paths after passing through diode D1, one path is connected to the node of resistors R2 and R3 in bridge A, the second path is connected to the node of resistors R2 and R4 after passing through the current detection resistor R1, and the third path is connected to the load circuit of the automatic ticket gate after passing through the current limiting resistor R15; the third path is connected to the backup power control circuit.

[0013] As a further improvement to the above technical solution:

[0014] One of the GPIO pins is electrically connected to a status indicator circuit.

[0015] The status indicator circuit includes a resistor R6 and an LED that are electrically connected to the GPIO pin.

[0016] The backup power control circuit includes transistor Q1 and MOSFET Q2, whose gate is electrically connected to the collector of transistor Q1;

[0017] One of the MCU's GPIO pins is connected to the base of transistor Q1 via a series diode D2 and resistor R7.

[0018] There is a resistor R10 between the base and emitter of transistor Q1; the emitter is grounded.

[0019] The drain of MOSFET Q2 is connected to the node of resistors R2 and R3 through diode D3; the node of resistors R2 and R3 is grounded through resistor R11.

[0020] VCC3 is directly connected to the source of MOSFET Q2 and connected to the gate of MOSFET Q2 through resistor R8;

[0021] There is a resistor R9 between the gate of MOSFET Q2 and the collector of transistor Q1;

[0022] A current-limiting resistor R15 is connected in series in the circuit where the current sensing resistor R1 is connected to the load circuit of the automatic ticket gate.

[0023] The current sensing amplifier circuit includes a U2C chip and an optocoupler;

[0024] Pin 4 of the optocoupler is grounded through resistor R14, and pins 5 and 7 are grounded; VCC3 is connected to pins 2 and 3 through reverse-connected diodes D4 and D5 respectively; VCC2 is connected to pins 1 and 8 through resistors R12 and R13 respectively; pin 8 is connected to pin 5 of the U2C chip, and pin 6 is connected to the GPIO pin of the MCU.

[0025] The automatic ticket gate load circuit includes a parallel terminating resistor R24 ​​and several emergency signal interface circuits;

[0026] The emergency signal interface circuit AG9 includes a transistor Q9A and a relay RELAY9.

[0027] The emitter of transistor Q9A is grounded at one end of resistor R24, and the base is connected to the current detection and amplification circuit through resistor R22 and the other end of resistor R24; the base is grounded through resistor R23; the collector is connected to the control coil of relay RELAY9.

[0028] The current sensing resistor R1 is located between the bus power supply VCC3 and the load of the automatic ticket gate machine.

[0029] When current flows from the bus power supply through the current sensing resistor R1 to the load of the automatic ticket checker, there is a voltage difference across the current sensing resistor R1. The voltage difference is fed into the IN+ and IN- input terminals of the chip U1, and the chip U1 amplifies and outputs the voltage difference value.

[0030] The automatic ticket checking machine can have up to ten load circuits.

[0031] A method for detecting the status of an emergency signal of a subway automatic ticket gate, comprising the aforementioned subway automatic ticket gate; the method includes the following steps;

[0032] S1, based on the resistance of the external load, calculate the minimum voltage reference value Vmin and the maximum voltage reference value Vmax under normal conditions;

[0033] S2, After the system starts, the MCU checks the input voltage of the input detection circuit to confirm the presence of the external input voltage;

[0034] If an external voltage is present, the MCU's AD detection will be activated directly to monitor the status of the external automatic ticket gate in real time.

[0035] If the external voltage is not available, the backup power control circuit is started through the GPIO pin of the MCU, and the backup power is used as the input voltage to power the system, and then the MCU's AD detection is enabled.

[0036] S3, through the current detection amplifier circuit, amplifies the voltage difference across the resistor through which the current is detected, and sends the amplified voltage difference to the AD pin of the MCU for real-time detection and analysis.

[0037] S4, the MCU compares the obtained voltage value with the reference values ​​Vmin and Vmax to determine whether the current state of the automatic ticket gate is normal.

[0038] As a further improvement to the above technical solution:

[0039] If the detected value is less than Vmin, the automatic ticket gate is considered to be in an open circuit state.

[0040] If the detected value is greater than Vmax, the automatic ticket gate is considered to be in a short circuit state.

[0041] If the detected value is between Vmin and Vmax, the automatic ticket gate is considered to be in normal working order.

[0042] S5. If the automatic ticket gate is in normal operation, the MCU control status indicator circuit is in state 1; if it is in a short circuit state, the MCU control status indicator circuit is in state 2.

[0043] If the circuit is open, the MCU control status indicator circuit is in state 3.

[0044] The MCU will upload status 1, 2, or 3;

[0045] Status 1, 2, or 3 uses lights and / or sounds.

[0046] This system utilizes current amplification technology and the principle of AD (Analog-to-Digital) conversion. A current amplifier amplifies a small current signal and converts it into an analog voltage signal for output. The output analog voltage signal is then converted into a digital voltage signal by the AD converter of the MCU (Microcontroller Unit). This digital signal is compared with a reference value to determine whether the automatic ticket machine is in an abnormal state (open circuit or short circuit indicates an abnormal state), and an alarm with lights and sounds is issued for any abnormal conditions.

[0047] The basic principle of current sense amplification is to place a current-sensing resistor in the sensing circuit between the bus power supply and the load. When current flows from the bus power supply through the current-sensing resistor to the load, a voltage difference will appear across the resistor. The voltage across the resistor is fed into the two input terminals of the current sense amplifier, the voltage difference is detected and amplified, and the amplified voltage difference is output through the output pin of the current sense amplifier, thus completing the process of converting the current value into a voltage value and amplifying the output.

[0048] Signals in a circuit exist as analog signals, which are continuous in time. Therefore, it is necessary to discretize continuous signals into digital signals. This is done by sampling the input analog signal at a series of selected instants and then converting these sampled values ​​into a digital output. Thus, the AD conversion process first samples the input analog voltage signal. After sampling, a hold period is entered, during which the sampled analog quantity is converted into a digital quantity and the conversion result is given according to a certain encoding format. Then, the next sampling begins.

[0049] The emergency signal interface circuit of the automatic ticket gate is connected to the load side of the system. Changes in the load side cause changes in the current in the system, resulting in changes in the voltage difference between the two input terminals of the current sensing amplifier, and further causing changes in the output voltage. Therefore, this system confirms whether the automatic ticket gate on the load side has experienced any abnormal conditions such as open circuits or short circuits by comparing the voltage difference between the sensing resistor on the load side and the bus voltage side.

[0050] This utility model is reasonably designed, low in cost, sturdy and durable, safe and reliable, simple to operate, time-saving and labor-saving, cost-saving, compact in structure and easy to use. Attached Figure Description

[0051] Figure 1 The overall circuit block diagram of this utility model.

[0052] Figure 2 This utility model presents a circuit diagram of a state detection system.

[0053] Figure 3 A schematic diagram of the automatic ticket checking machine of this utility model. Detailed Implementation

[0054] like Figures 1-3 As shown, the system consists of two parts: a status detection system circuit with electrical connections and an automatic ticket gate load circuit; where AGx represents the Automatic Gate, with 10 electrical connections.

[0055] The status detection system circuit includes an input detection circuit with electrical connection, a current detection amplification circuit, a backup power control circuit, a status indication circuit, a current detection resistor, a current limiting resistor, and other peripheral circuits, as well as an MCU.

[0056] The MCU has ADC pins and GPIO pins;

[0057] One of the GPIO pins is electrically connected to a status indicator circuit.

[0058] The ADC pin is electrically connected to the current detection and amplifier circuit.

[0059] The current detection amplifier circuit includes chip U1; in chip U1, pin 6 is connected to the ADC pin, pins 1 and 2 are grounded, pin 3 is connected to VCC1, and a bridge A consisting of resistors R2-4 and capacitor C1 is connected between pins 4 and 5; VCC3 is split into three paths after passing through diode D1: one path is connected to the node of resistors R2 and R3 in bridge A; the second path passes through the current detection resistor R1 and is connected to the node of resistors R2 and R4 respectively, and then passes through the current limiting resistor R15 and is connected to the load circuit of the automatic ticket gate; the third path is connected to the backup power control circuit.

[0060] The backup power control circuit includes transistor Q1 and MOSFET Q2, whose gate is electrically connected to the collector of transistor Q1;

[0061] One of the MCU's GPIO pins is connected to the base of transistor Q1 via a series diode D2 and resistor R7.

[0062] There is a resistor R10 between the base and emitter of transistor Q1; the emitter is grounded.

[0063] The drain of MOSFET Q2 is connected to the node of resistors R2 and R3 through diode D3; the node of resistors R2 and R3 is grounded through resistor R11.

[0064] VCC3 is directly connected to the source of MOSFET Q2 and connected to the gate of MOSFET Q2 through resistor R8;

[0065] There is a resistor R9 between the gate of MOSFET Q2 and the collector of transistor Q1;

[0066] A current-limiting resistor R15 is connected in series in the circuit where the current sensing resistor R1 is connected to the load circuit of the automatic ticket gate;

[0067] The current sensing amplifier circuit includes a U2C chip and an optocoupler;

[0068] Optocoupler pin 4 is grounded through resistor R14, and pins 5 and 7 are grounded; VCC3 is connected to pins 2 and 3 through reverse-connected diodes D4 and D5 respectively; VCC2 is connected to pins 1 and 8 through resistors R12 and R13 respectively; pin 8 is connected to pin 5 of the U2C chip, and pin 6 is connected to the GPIO pin of the MCU.

[0069] The main component of the automatic ticket gate's load circuit is the emergency signal interface circuit. The status detection system circuit is connected to the emergency signal interface circuit of the automatic ticket gate via a current-limiting resistor. The status of the automatic ticket gate is determined by judging the status of the emergency signal interface circuit. One status detection system circuit is electrically connected to 10 automatic ticket gates to form an automatic ticket gate group. A terminating resistor is connected in series in the last automatic ticket gate as a detection resistor.

[0070] The automatic ticket gate load circuit includes a parallel terminating resistor R24 ​​and several emergency signal interface circuits;

[0071] The emergency signal interface circuit AG9 includes a transistor Q9A and a relay RELAY9.

[0072] The emitter of transistor Q9A is grounded to one end of resistor R24, and the base is connected to a current detection and amplification circuit through resistor R22 and the other end of resistor R24; the base is grounded through resistor R23; the collector is connected to the control coil of relay RELAY9.

[0073] The working principle of this utility model is combined with Figure 1 , Figure 2 and Figure 3 The system works as follows:

[0074] After the system is powered on, the MCU, as the core of the system, first detects the presence of an external input voltage through the "input detection circuit". Only when an external input voltage is present can the current detection amplifier circuit work normally.

[0075] If no external voltage input is detected, the MCU will control the GPIO pin connected to the "backup power control circuit" to enable the backup voltage to power the system, and at the same time enable the AD detection function.

[0076] A current sensing resistor R1 (hereinafter referred to as R1) is placed between the bus power supply (input voltage / backup voltage) and the automatic ticket machine load. When current flows from the bus power supply through R1 to the automatic ticket machine load, a voltage difference will appear across the resistor. The detected values ​​across R1 are fed into the IN+ and IN- input terminals of the current sensing amplifier circuit to detect and amplify the voltage difference. The amplified voltage difference is then output through the OUT pin of the current sensing amplifier circuit, thus completing the process of converting the current value into a voltage value and amplifying the output.

[0077] The "current detection amplifier circuit" detects the voltage difference across R1, amplifies the value, and inputs it to the AD pin of the MCU through the OUT pin. The MCU then compares the data value detected by the AD pin with the calculated reference values ​​Vmin and Vmax to determine whether the automatic ticket gate is in normal condition, and displays the current status of the automatic ticket gate by controlling the "status indicator circuit".

[0078] The automatic ticket checking unit serves as an external load, connected between R1 and R4 via a current-limiting resistor R15 (hereinafter referred to as R15). The value of R1 is much smaller than that of R15. A set of automatic ticket checking units can connect to a maximum of 10 automatic ticket checking machines, with a terminating resistor R24 ​​(hereinafter referred to as R24) connected in series in the last automatic ticket checking machine as a detection resistor.

[0079] Taking 10 external automatic ticket gates as an example, since the value of the current sensing resistor R1 is much smaller than that of the current limiting resistor R15, when all 10 automatic ticket gates are in normal working order, the current value is:

[0080] I N =Vcc / (R 15 +R AG1 / / R AG2 / / … / / R AG9 / / R 24 );

[0081] When the automatic ticket gate is short-circuited, the current is:

[0082] I S =Vcc / R 15 ;

[0083] When all 10 automatic ticket gates are disconnected, the current value is 0;

[0084] When only the last of the 10 automatic ticket gates is functioning properly, and the other 9 are open-circuited, the current is:

[0085] I O9 =Vcc / (R 15 +R 24 )

[0086] Current value I of an automatic ticket gate under normal load conditions N In I S and I O9 between;

[0087] The number of external automatic ticket gates can be between 1 and 10, therefore the current value I of the automatic ticket gates under normal load conditions is... N In I S and I O9 Between. When the detected current value is less than I O9 When the detected current value is greater than or equal to I, it is determined that the automatic ticket gate's load is in an open circuit state; S If this occurs, the automatic ticket gate machine is determined to be in a short-circuit state.

[0088] In summary, the different states of the external automatic ticket gate can be converted into different current values ​​in the circuit, and then further converted into different voltage values ​​by the current detection and amplification circuit for judgment.

[0089] in, Figure 1 The lack of clarity does not affect the scope of protection of this utility model. The working process of the system is described as follows:

[0090] S1, based on the resistance of the external load, calculate the minimum voltage reference value Vmin and the maximum voltage reference value Vmax under normal conditions;

[0091] S2. After the system starts, the MCU checks the input voltage of the input detection circuit to confirm the existence of the external input voltage. If the external voltage exists, the AD detection is directly enabled to monitor the status of the external automatic ticket gate in real time. If the external voltage does not exist, the backup power control circuit is started through the GPIO (General-Purpose Input / Output) pin to use the backup power as the input voltage to power the system, and then the AD detection is enabled.

[0092] S3, through the current detection amplifier circuit, amplifies the voltage difference across the current detection resistor and sends the amplified voltage difference to the MCU's AD pin for real-time detection and analysis.

[0093] S4, the MCU compares the obtained voltage value with the reference values ​​Vmin and Vmax to determine whether the automatic ticket gate is in normal condition: if the detected value is less than Vmin, the automatic ticket gate is considered to be in an open circuit state; if the detected value is greater than Vmax, the automatic ticket gate is considered to be in a short circuit state; if the detected value is between Vmin and Vmax, the automatic ticket gate is considered to be in normal condition.

[0094] S5. If the automatic ticket gate is in normal operation, the MCU control status indicator circuit is in state 1; if it is in a short-circuit state, the MCU control status indicator circuit is in state 2; if it is in an open-circuit state, the MCU control status indicator circuit is in state 3, thus informing staff of the current status of the automatic ticket gate. (States 1 to 3 can be combinations of various light and sound signals, which can be determined according to user needs.)

[0095] This invention uses a current detection and amplification circuit to convert changes in load current into changes in voltage, and then detects these voltage changes using an MCU. It also uses an input detection circuit to detect the presence of an external input voltage; if the voltage is absent, a backup power supply is activated, ensuring the stability and continuity of the detection status. Furthermore, the MCU compares the detected voltage value with reference values ​​Vmin and Vmax to confirm the real-time status of the external automatic ticket checking machine. Finally, a status indicator circuit displays the real-time status of the emergency signals from the external automatic ticket checking machine.

[0096] This utility model is described in detail for the purpose of making the disclosure clearer, and the prior art will not be listed one by one.

[0097] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. It is obvious to those skilled in the art that multiple technical solutions of this utility model can be combined. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model. All technical contents not described in detail in this utility model are publicly known technologies.

Claims

1. A subway automatic ticket gate based on emergency signal status detection, characterized in that: This includes the electrical connection status detection system circuit and the automatic ticket checking unit load circuit; The condition detection system circuit includes an MCU and peripheral circuits electrically connected to the MCU; The peripheral circuitry includes an input detection circuit, a current detection amplifier circuit, a backup power control circuit, a status indicator circuit, and a current detection resistor, all of which are electrically connected to the MCU. The MCU has ADC pins and GPIO pins; The ADC pin is electrically connected to the current detection amplifier circuit. The current detection amplifier circuit includes chip U1; in chip U1, pin 6 is connected to the ADC pin, pins 1 and 2 are grounded, pin 3 is connected to VCC1, and a bridge A consisting of resistors R2-4 and capacitor C1 is connected between pins 4 and 5. After passing through diode D1, VCC3 is divided into three paths: one path is connected to the node between resistors R2 and R3 in bridge A; the second path is connected to the node between resistors R2 and R4 after passing through current sensing resistor R1, and then connected to the load circuit of the automatic ticket gate after passing through current limiting resistor R15; the third path is connected to the backup power control circuit.

2. The emergency signal based status detection of metro automatic ticket gates according to claim 1, characterized in that: in, One GPIO pin is electrically connected to a status indicator circuit; The status indicator circuit includes a resistor R6 and an LED that are electrically connected to the GPIO pin.

3. The emergency signal based status detection of metro automatic ticket checking machine according to claim 1, characterized in that: The backup power control circuit includes transistor Q1 and MOSFET Q2, whose gate is electrically connected to the collector of transistor Q1; One of the MCU's GPIO pins is connected to the base of transistor Q1 via a series diode D2 and resistor R7. There is a resistor R10 between the base and emitter of transistor Q1; the emitter is grounded. The drain of MOSFET Q2 is connected to the node of resistors R2 and R3 through diode D3; the node of resistors R2 and R3 is grounded through resistor R11. VCC3 is directly connected to the source of MOSFET Q2 and connected to the gate of MOSFET Q2 through resistor R8; There is a resistor R9 between the gate of MOSFET Q2 and the collector of transistor Q1; A current-limiting resistor R15 is connected in series in the circuit where the current sensing resistor R1 is connected to the load circuit of the automatic ticket gate.

4. The subway automatic ticket gate based on emergency signal status detection according to claim 1, characterized in that: The current sensing amplifier circuit includes a U2C chip and an optocoupler; Pin 4 of the optocoupler is grounded through resistor R14, and pins 5 and 7 are grounded; VCC3 is connected to pins 2 and 3 through reverse-connected diodes D4 and D5 respectively. VCC2 is connected to pin 1 and pin 8 via resistors R12 and R13 respectively; pin 8 is connected to pin 5 of the U2C chip, and pin 6 is connected to the GPIO pin of the MCU.

5. The subway automatic ticket gate based on emergency signal status detection according to claim 1, characterized in that: The automatic ticket checker load circuit includes a parallel terminating resistor R24 ​​and several emergency signal interface circuits; The emergency signal interface circuit AG9 includes a transistor Q9A and a relay RELAY9. The emitter of transistor Q9A is grounded at one end of resistor R24, and the base is connected to the current detection and amplification circuit through resistor R22 and the other end of resistor R24; the base is grounded through resistor R23; the collector is connected to the control coil of relay RELAY9.

6. The subway automatic ticket gate based on emergency signal status detection according to claim 1, characterized in that: The current sensing resistor R1 is located between the bus power supply VCC3 and the load of the automatic ticket gate machine.

7. The subway automatic ticket gate based on emergency signal status detection according to claim 1, characterized in that: When current flows from the bus power supply through the current sensing resistor R1 to the load of the automatic ticket checker, there is a voltage difference across the current sensing resistor R1. The voltage difference is fed into the IN+ and IN- input terminals of the chip U1, and the chip U1 amplifies and outputs the voltage difference value.

8. The subway automatic ticket gate based on emergency signal status detection according to claim 1, characterized in that: The automatic ticket checking machine has ten load circuits.

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