Device and method for extending the service life of a photoelectric sensor

Abstract

This invention discloses a device for extending the lifespan of a photoelectric sensor, comprising a photoelectric sensor, a light intensity adjustment module, and an MCU controller. The PWM terminal of the MCU controller is connected to the input terminal of the light intensity adjustment module, and the output terminal of the light intensity adjustment module is connected to the emitting terminal of the photoelectric sensor. This allows adjustment of the duty cycle of the PWM signal output by the MCU controller, and the control of the luminous current at the emitting terminal of the photoelectric sensor via the light intensity adjustment module, thereby regulating the light signal intensity at the emitting terminal of the photoelectric sensor. The ADC terminal of the MCU controller is connected to the receiving terminal of the photoelectric sensor to sample the voltage at the receiving terminal. Based on the MCU controller, this invention, through the light intensity adjustment module and the resistance adjustment module, controls the light intensity at the emitting terminal and the voltage at the receiving terminal of the photoelectric sensor, effectively delaying the problem of shortened lifespan due to light decay and enhancing the stability and accuracy of the photoelectric sensor in various environments.

Description

Technical Field

[0001] This invention relates to the field of photoelectric sensor technology, and more specifically, to a device and method for extending the service life of photoelectric sensors. Background Technology

[0002] In daily life and industrial applications, photoelectric sensors are favored due to their wide application in various fields. However, in practical applications, existing photoelectric sensors are inevitably affected by factors such as temperature, current, and working time, resulting in light decay. This seriously affects the machinery and equipment embedded with photoelectric sensors, significantly shortens the lifespan of industrial equipment, and affects the accuracy and stability of industrial equipment. At the same time, considering the timeliness and labor cost of troubleshooting light decay problems in industrial equipment, especially in remote areas where maintenance costs are high, the environment is harsh, and maintenance is difficult, delaying the impact of light decay on machines and timely feedback of anomalies have become the main directions for current solutions.

[0003] Existing patent CN216052701U discloses a photoelectric sensor light decay detection device. It receives current data signals from a current acquisition unit via a main control unit, calculates the actual current value on the photosensitive side of the photoelectric sensor, and sends it to a display unit. It also sends the acquisition time and actual current value to a data storage unit at preset time intervals to achieve automatic detection of photoelectric sensor light decay. However, this patent has a limited function, only detecting light decay current and unable to prevent the machine from being affected by light decay. Existing patent CN102708617B discloses a banknote detection method and device, as well as a photoelectric sensor adaptive adjustment method and device. This includes a photoelectric sensor, a micro-control unit, a digital-to-analog converter (DAC), a driver, and a current-limiting resistor. It adaptively adjusts the DAC value corresponding to the voltage at the photoelectric sensor's emitting end and compensates for this DAC value, thereby improving the photoelectric sensor's adaptability. However, this patent can only adjust the light intensity at the emitting end, cannot cope with severe light decay, and has limited time to extend the lifespan of the light-decaying sensor, thus exhibiting certain limitations. Summary of the Invention

[0004] In order to overcome the shortcomings of the existing technology, the present invention provides an apparatus and method for extending the service life of photoelectric sensors, which solves the problems of limited effect of existing devices in delaying the light decay life of photoelectric sensors and inability to provide timely feedback on photoelectric sensor abnormalities.

[0005] To achieve the above technical objectives, the following technical solution is adopted:

[0006] In a first aspect, embodiments of the present invention provide an apparatus for extending the service life of a photoelectric sensor, including a photoelectric sensor, and further including a light intensity adjustment module and an MCU controller;

[0007] The PWM terminal of the MCU controller is connected to the input terminal of the light intensity adjustment module, and the output terminal of the light intensity adjustment module is connected to the emitting terminal of the photoelectric sensor. This is used to adjust the duty cycle of the PWM signal output by the MCU controller and to regulate the light emission current of the emitting terminal of the photoelectric sensor by the light intensity adjustment module, thereby adjusting the light signal intensity of the emitting terminal of the photoelectric sensor.

[0008] The ADC terminal of the MCU controller is connected to the receiving terminal of the photoelectric sensor to sample the voltage at the receiving terminal of the photoelectric sensor.

[0009] Furthermore, it also includes a resistance adjustment module, which includes a first resistance adjustment unit, a second resistance adjustment unit, a first switch K1, and a second switch K2; the input terminal of the first resistance adjustment unit is connected to the first control terminal of the MCU controller through the first switch K1, and the output terminal of the first resistance adjustment unit is connected to the receiving terminal of the photoelectric sensor.

[0010] The input terminal of the second resistance adjustment unit is connected to the second control terminal of the MCU controller through the second switch K2, and the output terminal of the second resistance adjustment unit is connected to the receiving terminal of the photoelectric sensor.

[0011] Furthermore, it also includes a host computer, which is connected to the MCU controller to receive abnormal signals from the photoelectric sensor fed back by the MCU controller, and to regulate the photoelectric sensor through the MCU controller.

[0012] Furthermore, the light intensity modulation unit includes a field-effect transistor Q1, a resistor R1, a resistor R2, and a resistor R3;

[0013] The drain of the field-effect transistor Q1 is connected to the emitter of the photoelectric sensor, the source of the field-effect transistor Q1 is grounded through resistor R1, and the gate of the field-effect transistor Q1 is connected to the PWM terminal of the MCU controller through resistor R2; one end of the resistor R3 is connected to the gate of the field-effect transistor Q1, and the other end is grounded.

[0014] Furthermore, the first regulating resistor unit includes a field-effect transistor Q2, a resistor R4, a resistor R5, and a resistor R6;

[0015] The drain of the field-effect transistor Q2 is connected to the emitter of the photoelectric sensor, and the source of the field-effect transistor Q2 is grounded through resistor R4; the gate of the field-effect transistor Q2 is connected in sequence to resistor R5, the first switch K1 and the first control terminal of the MCU controller.

[0016] One end of the resistor R6 is connected to the first switch K1, and the other end is grounded; the ADC terminal of the MCU controller is connected to the drain of the field-effect transistor Q2.

[0017] Furthermore, the second regulating resistor unit includes a field-effect transistor Q3, resistors R7, R8, and R9;

[0018] The drain of the field-effect transistor Q3 is connected to the emitter of the photoelectric sensor, and the source of the field-effect transistor Q3 is grounded through resistor R7; the gate of the field-effect transistor Q3 is connected in sequence to resistor R8, second switch K2 and the second control terminal of the MCU controller.

[0019] One end of the resistor R9 is connected to the second switch K2, and the other end is grounded; the ADC terminal of the MCU controller is connected to the drain of the field-effect transistor Q3.

[0020] Furthermore, the emitting end of the photoelectric sensor is an infrared emitting tube, and the receiving end of the photoelectric sensor is an infrared receiving tube; the infrared receiving tube is a phototransistor.

[0021] The anode of the infrared emitting diode is connected to the first power supply voltage terminal, and the cathode of the infrared emitting diode is connected to the PWM terminal of the MCU controller through the light intensity adjustment module.

[0022] The collector of the infrared receiver is connected to the second power supply voltage terminal, and the emitter of the infrared receiver is connected to the first resistance adjustment unit and the second resistance adjustment unit respectively.

[0023] Secondly, embodiments of the present invention provide a method for extending the lifespan of a photoelectric sensor, applied to the apparatus described above, comprising:

[0024] S1. Send a calibration command to the MCU controller via the host computer and set the calibration success threshold V. ref ;

[0025] S2. After receiving the calibration command, the MCU controller samples the voltage at the receiving end of the photoelectric sensor through the MCU controller's ADC terminal to obtain the sampled voltage V. ADC ;

[0026] S3. Determine the working status of the photoelectric sensor and decide whether the photoelectric sensor needs to be calibrated based on the working status.

[0027] S3 specifically includes the following steps:

[0028] S31, Sample voltage V ADC With calibration success threshold V ref Compare;

[0029] S32, when V ADC ≥V ref If the photoelectric sensor is in normal working condition, then the photoelectric sensor does not need to be calibrated.

[0030] S33, when V ADC <V ref If the light decays, the photoelectric sensor is considered to be in a state of light decay. At this time, the automatic calibration mechanism is triggered to calibrate the photoelectric sensor. If the calibration is successful, the duty cycle of the PWM signal at the sensor's transmitter is saved, and the photoelectric sensor can be used normally. If the calibration fails, the life extension mechanism is triggered to recalibrate the photoelectric sensor.

[0031] Furthermore, in step S33, the specific steps of the automatic calibration mechanism include:

[0032] By adjusting the duty cycle of the PWM signal output by the MCU controller, the light signal intensity at the photoelectric sensor's transmitter can be adjusted, thereby changing the emitter voltage V at the photoelectric sensor's transmitter. RD ;

[0033] The emitter voltage V of the infrared receiver tube RD With calibration success threshold V ref Compare;

[0034] When V RD ≥V ref If the result is positive, the photoelectric sensor calibration is considered successful.

[0035] When V R <V ref If so, the photoelectric sensor calibration is considered to have failed;

[0036] The emitter voltage V of the infrared receiver tube RD The calculation formula is:

[0037] V RD =V ADC

[0038] V ADC =I E ·R E

[0039] I E = (1+β)·I B

[0040] Where, I E I is the emitter current of the infrared receiver tube. B R is the luminous current of the infrared emitter; E β is the pull-down resistor for the infrared receiver; β is the amplification factor of the infrared receiver.

[0041] The luminous current I of the infrared emitting diode B The calculation formula is:

[0042]

[0043] In the formula, V is the first power supply voltage, V f θ is the conduction voltage of the infrared emitting diode; PWM is the duty cycle of the PWM signal; α is the light attenuation coefficient; θ1 is the influence coefficient of the installation distance and angle offset of the photoelectric sensor (0≦θ1≦1); θ2 is the dust and environmental influence coefficient.

[0044] Furthermore, in S33, the specific steps of triggering the lifetime extension mechanism include:

[0045] S331. Open the first switch K1, close the second switch K2, and adjust the pull-down resistor value to the first resistance value to change the emitter voltage V of the infrared receiver tube. RD The photoelectric sensor is calibrated, and it is determined whether the photoelectric sensor is calibrated successfully. If the calibration fails, the calibration is continued through step S332.

[0046] S332. Close the first switch K1, open the second switch K2, and adjust the pull-down resistor value to the second resistance value to change the emitter voltage V of the infrared receiver tube. RD The photoelectric sensor is recalibrated, and it is determined whether the photoelectric sensor has been successfully calibrated.

[0047] The process of determining whether the photoelectric sensor has been successfully calibrated includes the following steps:

[0048] The emitter voltage V of the infrared receiver tube RD With calibration success threshold V ref Compare;

[0049] When V RD ≥V ref If the photoelectric sensor is successfully calibrated, the duty cycle of the PWM signal at the sensor's transmitter is saved, the photoelectric sensor is in normal use, and an alarm signal is sent to the host computer, which then controls the photoelectric sensor.

[0050] When V RD <V ref If the result is not met, the photoelectric sensor calibration is considered to have failed.

[0051] The beneficial effects of the embodiments provided by the present invention include:

[0052] This invention, based on an MCU controller, uses an intensity adjustment module and a resistance adjustment module to regulate the light intensity at the transmitting end and the voltage at the receiving end of a photoelectric sensor. This effectively mitigates the problem of shortened lifespan due to light decay in the photoelectric sensor, enhancing its stability and accuracy in various environments. Furthermore, this invention receives abnormal signals from the photoelectric sensor from the MCU controller via a host computer and sends calibration commands to the MCU controller to calibrate the sensor. This enables early warning and handling of photoelectric sensor malfunctions, reducing troubleshooting and replacement work and lowering labor costs. The invention is simple in structure, low in cost, and can be freely adjusted according to actual usage, making it adaptable to various scenarios and easy to implement. Attached Figure Description

[0053] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0054] Figure 1 A circuit diagram of a device for extending the lifespan of a photoelectric sensor, provided in an embodiment of the present invention:

[0055] Figure 2 A schematic diagram of a device module for extending the service life of a photoelectric sensor, provided in an embodiment of the present invention;

[0056] Figure 3 This is a schematic flowchart of a method for extending the service life of a photoelectric sensor, provided as an embodiment of the present invention. Detailed Implementation

[0057] To make the objectives, technical solutions and advantages of this disclosure clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0058] However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of this disclosure. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of embodiments of this disclosure for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known technologies are omitted in the following description to avoid unnecessarily obscuring the concepts of this disclosure.

[0059] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The term "comprising" as used herein indicates the presence of features, steps, or operations, but does not exclude the presence or addition of one or more other features. It should be noted that all terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be understood that the terms used herein should be interpreted in a manner consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0060] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0061] Example 1

[0062] like Figure 1-Figure 2 As shown, this embodiment of the invention provides a device for extending the service life of a photoelectric sensor, including a photoelectric sensor, a light intensity adjustment module, an MCU controller, and a resistance adjustment module;

[0063] In some embodiments, the PWM terminal of the MCU controller is connected to the input terminal of the light intensity adjustment module, and the output terminal of the light intensity adjustment module is connected to the emitting terminal of the photoelectric sensor. This is used to adjust the duty cycle of the PWM signal output by the MCU controller and to regulate the light emission current of the emitting terminal of the photoelectric sensor by the light intensity adjustment module, thereby adjusting the light signal intensity of the emitting terminal of the photoelectric sensor.

[0064] The ADC terminal of the MCU controller is connected to the receiving terminal of the photoelectric sensor to sample the voltage at the receiving terminal of the photoelectric sensor.

[0065] In this embodiment, the resistance adjustment module includes a first resistance adjustment unit, a second resistance adjustment unit, a first switch K1, and a second switch K2.

[0066] Specifically, the input terminal of the first resistance adjustment unit is connected to the first control terminal of the MCU controller through the first switch K1, and the output terminal of the first resistance adjustment unit is connected to the receiving terminal of the photoelectric sensor; the input terminal of the second resistance adjustment unit is connected to the second control terminal of the MCU controller through the second switch K2, and the output terminal of the second resistance adjustment unit is connected to the receiving terminal of the photoelectric sensor.

[0067] In some embodiments, the device further includes a host computer connected to an MCU controller, which is used to receive abnormal signals from the photoelectric sensor fed back by the MCU controller and to regulate the photoelectric sensor through the MCU controller.

[0068] In some embodiments, the light intensity modulation unit includes a field-effect transistor Q1, a resistor R1, a resistor R2, and a resistor R3;

[0069] Specifically, the drain of the field-effect transistor Q1 is connected to the emitter of the photoelectric sensor, the source of the field-effect transistor Q1 is grounded through resistor R1, and the gate of the field-effect transistor Q1 is connected to the PWM terminal of the MCU controller through resistor R2; one end of resistor R3 is connected to the gate of the field-effect transistor Q1, and the other end is grounded.

[0070] In some embodiments, the first regulating resistor unit includes a field-effect transistor Q2, a resistor R4, a resistor R5, and a resistor R6;

[0071] Specifically, the drain of the field-effect transistor Q2 is connected to the emitter of the photoelectric sensor and the ADC terminal of the MCU controller, respectively, and the source of the field-effect transistor Q2 is grounded through resistor R4; the gate of the field-effect transistor Q2 is connected in sequence to resistor R5, the first switch K1 and the first control terminal of the MCU controller.

[0072] One end of resistor R6 is connected to the first switch K1, and the other end is grounded.

[0073] In some embodiments, the second regulating resistor unit includes a field-effect transistor Q3, a resistor R7, a resistor R8, and a resistor R9;

[0074] Specifically, the drain of the field-effect transistor Q3 is connected to the emitter of the photoelectric sensor and the ADC terminal of the MCU controller, respectively, and the source of the field-effect transistor Q3 is grounded through resistor R7; the gate of the field-effect transistor Q3 is connected to resistor R8, the second switch K2 and the second control terminal of the MCU controller in sequence; one end of resistor R9 is connected to the second switch K2, and the other end is grounded;

[0075] In some embodiments, the emitting end of the photoelectric sensor is an infrared emitting tube, and the receiving end of the photoelectric sensor is an infrared receiving tube; the infrared receiving tube is a phototransistor.

[0076] Specifically, the anode of the infrared emitting diode is connected to the first power supply voltage terminal, and the cathode of the infrared emitting diode is connected to the PWM terminal of the MCU controller through the light intensity adjustment module; the collector of the infrared receiving diode is connected to the second power supply voltage terminal, and the emitter of the infrared receiving diode is connected to the first resistance adjustment unit and the second resistance adjustment unit respectively.

[0077] In this embodiment, the first power supply voltage is 5V and the second power supply voltage is 3.3V.

[0078] Example 2

[0079] This embodiment provides a method for extending the lifespan of a photoelectric sensor, applied to the device described in Embodiment 1, including:

[0080] The host computer sends a calibration command to the MCU controller and sets the calibration success threshold V. ref ;

[0081] After receiving the calibration command, the MCU controller samples the voltage at the receiver of the photoelectric sensor through the MCU controller's ADC terminal to obtain the sampled voltage V. ADC ;

[0082] Sample voltage V ADC With calibration success threshold V ref Comparison, when V ADC ≥V ref If the photoelectric sensor is in normal working condition, then the photoelectric sensor does not need to be calibrated.

[0083] When V ADC <V ref If the light decays, the sensor is considered to have experienced light decay. At this time, the automatic calibration mechanism is triggered to calibrate the photoelectric sensor. If the calibration is successful, the duty cycle of the PWM signal at the sensor's transmitter is saved, and the photoelectric sensor can be used normally. If the calibration fails, the lifespan extension mechanism is triggered to recalibrate the photoelectric sensor.

[0084] In some embodiments, the specific steps of the automatic calibration mechanism include:

[0085] By adjusting the duty cycle of the PWM signal output by the MCU controller, the light signal intensity at the photoelectric sensor's transmitter can be adjusted, thereby changing the emitter voltage V at the photoelectric sensor's transmitter. RD ;

[0086] The emitter voltage V of the infrared receiver tube RD With calibration success threshold V ref Compare;

[0087] When V RD ≥V ref If the result is positive, the photoelectric sensor calibration is considered successful.

[0088] When V RD <V ref If the result is not met, the photoelectric sensor calibration is considered to have failed.

[0089] In this embodiment, by increasing the duty cycle of the PWM signal output by the MCU controller, the conduction time of the field-effect transistor Q1 in the light intensity modulation module is increased, thereby increasing the luminous current at the photoelectric sensor's emitter and enhancing the light signal intensity at the photoelectric sensor's emitter, thus increasing the emitter voltage V at the photoelectric sensor's emitter. RD Increase the size to bring the photoelectric sensor into normal working condition.

[0090] Specifically, the emitter voltage V of the infrared receiver tube RD The calculation formula is:

[0091] V RD =V ADC

[0092] V ADC =I E ·R E

[0093] I E = (1+β)·I B

[0094] Where, I E I is the emitter current of the infrared receiver tube. B R is the luminous current of the infrared emitter; E β is the pull-down resistor for the infrared receiver; β is the amplification factor of the infrared receiver.

[0095] In this embodiment, the pull-down resistor R of the infrared receiver tube E The values ​​can be 10K, 15K, or 30K. When the calibration success threshold V is set... ref At that time, R E Take 10K.

[0096] Specifically, the luminous current I of the infrared emitting diode B The calculation formula is:

[0097]

[0098] In the formula, V f θ is the conduction voltage of the infrared emitting diode; PWM is the duty cycle of the PWM signal; α is the light attenuation coefficient; θ1 is the influence coefficient of the installation distance and angle offset of the photoelectric sensor (0≦θ1≦1); θ2 is the dust and environmental influence coefficient.

[0099] In some embodiments, the specific steps for triggering the lifetime extension mechanism include:

[0100] Turn on the first switch K1, turn off the second switch K2, adjust the pull-down resistor value to 15K, trigger the automatic calibration mechanism, and calibrate the photoelectric sensor;

[0101] When the photoelectric sensor is successfully calibrated, the duty cycle of the PWM signal can be adjusted back to 0%-100%. The duty cycle of the PWM signal at the sensor's transmitter is saved at this time. The photoelectric sensor is in normal use and sends an alarm signal to the host computer. The host computer can then control the photoelectric sensor.

[0102] When the photoelectric sensor calibration fails, turn off the first switch K1, turn on the second switch K2, adjust the pull-down resistor value to 30K, trigger the automatic calibration mechanism, and recalibrate the photoelectric sensor.

[0103] If the calibration is successful, the duty cycle of the PWM signal at the sensor's transmitter is saved, and the photoelectric sensor can be used normally.

[0104] If calibration fails, the photoelectric sensor is considered unusable.

[0105] In this embodiment, the photoelectric sensor sends an alarm signal to the host computer to remind the user that the photoelectric sensor has experienced light decay and needs to be protected to extend its lifespan. The host computer should control the start and stop of the photoelectric sensor according to the actual situation and minimize the use of the sensor as much as possible.

[0106] In summary, this invention, through intensity modulation and resistance adjustment, can effectively delay the shortened lifespan of photoelectric sensors due to light decay, and enhance the stability and accuracy of photoelectric sensors in various environments. Before the photoelectric sensor is calibrated, both the first switch K1 and the second switch K2 are open, at which point the pull-down resistor R... E The value is 10k, and the pull-down resistor R is used when the lifetime extension mechanism is triggered. E At 30kΩ, this is equivalent to amplifying the photoelectric signal by a factor of 3, which can greatly extend the sensor's lifespan and allow the photoelectric sensor to be salvaged even in cases of severe light decay. Furthermore, in practical applications, the pull-down resistor R can be used... E Adjusting the resistance to a higher value enhances the effectiveness of the lifespan extension mechanism. This invention receives abnormal signals from the photoelectric sensor from the MCU controller via a host computer and sends calibration commands to the MCU controller to calibrate the photoelectric sensor. This enables early warning and remote handling of photoelectric sensor malfunctions, reducing troubleshooting and replacement work and lowering labor costs. The invention is simple in structure, low in cost, and can be freely adjusted according to actual usage, making it adaptable to various scenarios and easy to implement.

[0107] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for extending the service life of a photoelectric sensor, applied to a device for extending the service life of a photoelectric sensor, characterized in that, include: S1. Send a calibration command to the MCU controller via the host computer and set the calibration success threshold V. ref ; S2. After receiving the calibration command, the MCU controller samples the voltage at the receiving end of the photoelectric sensor through the MCU controller's ADC terminal to obtain the sampled voltage V. ADC ; S3. Determine the working status of the photoelectric sensor and decide whether the photoelectric sensor needs to be calibrated based on the working status. S3 specifically includes the following steps: S31, Sample voltage V ADC With calibration success threshold V ref Compare; S32, when V ADC ≥V ref If the photoelectric sensor is in normal working condition, then the photoelectric sensor does not need to be calibrated. S33, when V ADC <V ref If the light decays, the photoelectric sensor is considered to be in a state of light decay. At this time, the automatic calibration mechanism is triggered to calibrate the photoelectric sensor. If the calibration is successful, the duty cycle of the PWM signal at the sensor's transmitting end is saved, and the photoelectric sensor is used normally. If calibration fails, the lifetime extension mechanism is triggered to recalibrate the photoelectric sensor. In step S33, the specific steps of the triggered lifetime extension mechanism include: S331. Open the first switch K1, close the second switch K2, and adjust the pull-down resistor value to the first resistance value to change the emitter voltage V of the infrared receiver tube. RD The photoelectric sensor is calibrated, and it is determined whether the photoelectric sensor is calibrated successfully. If the calibration fails, the calibration is continued through step S332. S332. Close the first switch K1, open the second switch K2, and adjust the pull-down resistor value to the second resistance value to change the emitter voltage V of the infrared receiver tube. RD The photoelectric sensor is recalibrated, and it is determined whether the photoelectric sensor has been successfully calibrated. The process of determining whether the photoelectric sensor has been successfully calibrated includes the following steps: The emitter voltage V of the infrared receiver tube RD With calibration success threshold V ref Compare; When V RD ≥V ref If the photoelectric sensor is successfully calibrated, the duty cycle of the PWM signal at the sensor's transmitter is saved, the photoelectric sensor is in normal use, and an alarm signal is sent to the host computer, which then controls the photoelectric sensor. When V RD <V ref If so, the photoelectric sensor calibration is considered to have failed; The device includes a photoelectric sensor, a light intensity adjustment module, an MCU controller, and a resistance adjustment module; The PWM terminal of the MCU controller is connected to the input terminal of the light intensity adjustment module, and the output terminal of the light intensity adjustment module is connected to the emitting terminal of the photoelectric sensor. This is used to adjust the duty cycle of the PWM signal output by the MCU controller and to regulate the light emission current of the emitting terminal of the photoelectric sensor by the light intensity adjustment module, thereby adjusting the light signal intensity of the emitting terminal of the photoelectric sensor. The ADC terminal of the MCU controller is connected to the receiving terminal of the photoelectric sensor to sample the voltage at the receiving terminal of the photoelectric sensor. The resistance adjustment module includes a first resistance adjustment unit, a second resistance adjustment unit, a first switch K1, and a second switch K2; the input terminal of the first resistance adjustment unit is connected to the first control terminal of the MCU controller through the first switch K1, and the output terminal of the first resistance adjustment unit is connected to the receiving terminal of the photoelectric sensor. The input terminal of the second resistance adjustment unit is connected to the second control terminal of the MCU controller through the second switch K2, and the output terminal of the second resistance adjustment unit is connected to the receiving terminal of the photoelectric sensor.

2. The method according to claim 1, characterized in that, The device also includes a host computer, which is connected to an MCU controller to receive abnormal signals from the photoelectric sensor fed back by the MCU controller and to regulate the photoelectric sensor through the MCU controller.

3. The method according to claim 1, characterized in that, The light intensity modulation module includes a field-effect transistor Q1, resistors R1, R2, and R3; The drain of the field-effect transistor Q1 is connected to the emitter of the photoelectric sensor, the source of the field-effect transistor Q1 is grounded through resistor R1, and the gate of the field-effect transistor Q1 is connected to the PWM terminal of the MCU controller through resistor R2; one end of the resistor R3 is connected to the gate of the field-effect transistor Q1, and the other end is grounded.

4. The method according to claim 1, characterized in that, The first resistor adjustment unit includes a field-effect transistor Q2, resistor R4, resistor R5, and resistor R6; The drain of the field-effect transistor Q2 is connected to the emitter of the photoelectric sensor, and the source of the field-effect transistor Q2 is grounded through resistor R4; the gate of the field-effect transistor Q2 is connected in sequence to resistor R5, the first switch K1 and the first control terminal of the MCU controller. One end of the resistor R6 is connected to the first switch K1, and the other end is grounded; the ADC terminal of the MCU controller is connected to the drain of the field-effect transistor Q2.

5. The method according to claim 1, characterized in that, The second resistor adjustment unit includes a field-effect transistor Q3, resistors R7, R8, and R9; The drain of the field-effect transistor Q3 is connected to the emitter of the photoelectric sensor, and the source of the field-effect transistor Q3 is grounded through resistor R7; the gate of the field-effect transistor Q3 is connected in sequence to resistor R8, second switch K2 and the second control terminal of the MCU controller. One end of the resistor R9 is connected to the second switch K2, and the other end is grounded; the ADC terminal of the MCU controller is connected to the drain of the field-effect transistor Q3.

6. The method according to claim 1, characterized in that, The emitting end of the photoelectric sensor is an infrared emitting tube, and the receiving end of the photoelectric sensor is an infrared receiving tube; the infrared receiving tube is a phototransistor. The anode of the infrared emitting diode is connected to the first power supply voltage terminal, and the cathode of the infrared emitting diode is connected to the PWM terminal of the MCU controller through the light intensity adjustment module. The collector of the infrared receiver is connected to the second power supply voltage terminal, and the emitter of the infrared receiver is connected to the first resistance adjustment unit and the second resistance adjustment unit respectively.

7. The method according to claim 3, characterized in that, In step S33, the specific steps of the automatic calibration mechanism include: By adjusting the duty cycle of the PWM signal output by the MCU controller, the light signal intensity at the photoelectric sensor's transmitter can be adjusted, thereby changing the emitter voltage V at the photoelectric sensor's transmitter. RD ; The emitter voltage V of the infrared receiver tube RD With calibration success threshold V ref Compare; When V RD ≥V ref If the result is positive, the photoelectric sensor calibration is considered successful. When V RD <V ref If so, the photoelectric sensor calibration is considered to have failed; The emitter voltage V of the infrared receiver tube RD The calculation formula is: V RD =V ADC ; V ADC =I E ·R E ; I E =(1+β)•I B ; Where, I E I is the emitter current of the infrared receiver tube. B R is the luminous current of the infrared emitter; E β is the pull-down resistor for the infrared receiver; β is the amplification factor of the infrared receiver. The luminous current I of the infrared emitting diode B The calculation formula is: I B = ·PWM·ɑ·θ1·θ2 ; In the formula, V is the first power supply voltage. θ is the conduction voltage of the infrared emitting diode; PWM is the duty cycle of the PWM signal; α is the light attenuation coefficient; θ1 is the influence coefficient of the installation distance and angle offset of the photoelectric sensor, 0≦θ1≦1; θ2 is the dust and environmental influence coefficient.

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