Multi-mode composite photoelectric sensor circuit

Abstract

This application discloses a multi-mode composite photoelectric sensor circuit. The circuit includes: a mode switching unit for generating a first switching signal, a second switching signal, or a third switching signal; a control unit for outputting a first control signal, a second control signal, or a third control signal according to different switching signals; a light emitting unit for receiving a first control signal and emitting a first light signal, receiving a second control signal and emitting a second light signal, and receiving a third control signal and disabling the light emission function; a switching unit for receiving a first control signal or a third control signal to turn on the control unit and the light receiving unit, and receiving a second control signal to turn off the control unit and the light receiving unit; and a light receiving unit for receiving externally fed-in light signals, converting the light signals into electrical signals, and performing electrical signal processing to generate a detection electrical signal. This application can flexibly switch between different modes according to different switching signals, improving the versatility, flexibility, and reliability of the sensor.

Description

Technical Field

[0001] This application relates to the field of optoelectronic sensing technology, specifically to a multi-mode composite optoelectronic sensor circuit. Background Technology

[0002] Photoelectric sensors are widely used in industrial automation inspection, intelligent warehouse identification, security monitoring, and other scenarios. Their core function is to sense the presence, location, and distance of objects through the emission, propagation, and reception of light signals. Traditional photoelectric sensors mostly adopt a single working mode design and are mainly divided into two categories: diffuse reflection and through-beam. Diffuse reflection sensors detect objects by emitting light signals at the transmitter and receiving the reflected light signals at the receiver. Through-beam sensors, on the other hand, require independent transmitter and receiver sensors to work together, emitting light signals at the transmitter and receiving direct light signals (or sensing the state of light signal obstruction) at the receiver to achieve detection.

[0003] To meet different detection needs, related technologies require the design of independent sensor circuits for the three functions of diffuse reflection, through-beam transmitter, and through-beam receiver. However, the problem with this approach of designing different sensors for different detection needs is that multiple circuit schemes need to be developed, resulting in a wide variety of sensor models and increased R&D, production, and inventory costs. Furthermore, in practical applications, different sensors need to be replaced to adapt to different scenarios, increasing the complexity of installation and debugging, reducing equipment flexibility, and making it difficult to meet the needs of rapid detection in multiple scenarios. Utility Model Content

[0004] In view of the above problems, this application provides a multi-mode composite photoelectric sensor circuit to solve the above technical problems.

[0005] This application provides a multi-mode composite photoelectric sensor circuit, including:

[0006] A mode switching unit is used to generate a first switching signal, a second switching signal, or a third switching signal;

[0007] The control unit is connected to the mode switching unit and is used to output a first control signal according to a first switching signal, output a second control signal according to a second switching signal, and output a third control signal according to a third switching signal.

[0008] The light emitting unit is connected to the control unit and is used to receive a first control signal to emit a first light signal; receive a second control signal to emit a second light signal; and receive a third control signal to disable the light emission function.

[0009] The switching unit and the optical receiving unit are respectively connected to the control unit and the optical receiving unit. The switching unit is used to receive a first control signal or a third control signal to turn on the signal transmission path of the control unit and the optical receiving unit, and to receive a second control signal to turn off the signal transmission path of the control unit and the optical receiving unit.

[0010] An optical receiving unit is used to receive optical signals fed back from the outside, convert the optical signals into electrical signals, process the electrical signals to generate detection electrical signals, and output them to the control unit so that the control unit can output detection results.

[0011] The first switching signal is used to control the multi-mode composite photoelectric sensor circuit to work as a diffuse reflection photoelectric sensor, the second switching signal is used to control the multi-mode composite photoelectric sensor circuit to work as the transmitter of a through-beam photoelectric sensor, and the third switching signal is used to control the multi-mode composite photoelectric sensor circuit to work as the receiver of a through-beam photoelectric sensor.

[0012] The multi-mode composite photoelectric sensor circuit provided in this application generates different first, second, and third switching signals through a mode switching unit. The control unit outputs first, second, and third control signals respectively based on these different switching signals, thereby controlling the light emitting unit to emit a first or second light signal, or disabling its light emission function. Simultaneously, a switching unit, under the action of the first or third control signal, connects the signal transmission path between the light receiving unit and the control unit; under the action of the second control signal, it disconnects the signal transmission path. This allows the light receiving unit to receive external feedback light signals and convert them into detection electrical signals for the control unit to generate detection results. This enables reliable switching of a single photoelectric sensor between diffuse reflection mode, through-beam emitting mode, and through-beam receiving mode. This technical solution solves the problems of high cost, large inventory pressure, complex installation, and poor flexibility caused by the need to produce and use multiple independent products for different detection modes in existing photoelectric sensors. It significantly reduces production and procurement costs, reduces inventory, simplifies installation and maintenance, improves sensor versatility and adaptability, and ensures accurate and reliable signal transmission paths in each mode.

[0013] These or other aspects of this application will become more apparent in the following description of the embodiments. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 A schematic diagram of the multi-mode composite photoelectric sensor circuit provided in an embodiment of this application is shown.

[0016] Figure 2A schematic diagram of the mode switching unit provided in an embodiment of this application is shown.

[0017] Figure 3 A schematic diagram of the structure of the optical emitting unit provided in an embodiment of this application is shown.

[0018] Figure 4 A schematic diagram of the structure of the switching unit provided in an embodiment of this application is shown.

[0019] Figure 5 A schematic diagram of the structure of the optical receiving unit provided in an embodiment of this application is shown.

[0020] Figure 6 This paper shows another schematic diagram of a multi-mode composite photoelectric sensor circuit provided in an embodiment of this application.

[0021] Figure 7 A schematic diagram of the structure of the output unit provided in an embodiment of this application is shown. Detailed Implementation

[0022] To enable those skilled in the art to better understand the solutions of this application, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0023] In the embodiments of this application, it should be noted that, in this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0024] It should be noted that in the embodiments of this application, "connection" can be understood as electrical connection. The connection between two electrical components can be a direct or indirect connection between the two electrical components. For example, the connection between A and B can be a direct connection between A and B, or an indirect connection between A and B through one or more other electrical components.

[0025] Figure 1 The following is a schematic diagram of a module of a multi-mode composite photoelectric sensor circuit provided in an embodiment of this application, as shown below. Figure 1 As shown, the multi-mode composite photoelectric sensor circuit includes a mode switching unit, a control unit, a light emitting unit, a switching unit, and a light receiving unit.

[0026] A mode switching unit generates a first switching signal, a second switching signal, or a third switching signal. A control unit connected to the mode switching unit outputs a first control signal based on the first switching signal, a second control signal based on the second switching signal, and a third control signal based on the third switching signal. A light emitting unit connected to the control unit receives the first control signal and emits a first light signal; receives the second control signal and emits a second light signal; receives the third control signal and disables the light emission function. A switching unit connected to both the control unit and the light receiving unit receives the first or third control signal to connect the signal transmission path between the control unit and the light receiving unit, and receives the second control signal to disconnect the signal transmission path between the control unit and the light receiving unit. The light receiving unit receives externally fed-back light signals, converts the light signals into electrical signals, processes the electrical signals to generate a detection electrical signal, and outputs it to the control unit so that the control unit outputs a detection result. Specifically, the first switching signal controls the multi-mode composite photoelectric sensor circuit to operate as a diffuse reflection photoelectric sensor, the second switching signal controls the multi-mode composite photoelectric sensor circuit to operate as the emitting end of a through-beam photoelectric sensor, and the third switching signal controls the multi-mode composite photoelectric sensor circuit to operate as the receiving end of a through-beam photoelectric sensor.

[0027] Optionally, when the multi-mode composite photoelectric sensor circuit operates as a diffuse reflection photoelectric sensor, both the light emitting unit and the light receiving unit of the sensor circuit need to participate. Specifically, the mode switching unit outputs a first switching signal to the control unit, and the control unit outputs a first control signal accordingly. On the one hand, it drives the light emitting unit to emit a first light signal, which directly illuminates the target object in the area to be detected. On the other hand, it controls the switching unit to conduct the signal transmission path between the control unit and the light receiving unit. When the first light signal encounters the target object, it is reflected by the object's surface. The light receiving unit receives the reflected light signal and converts it into a weak electrical signal. Then, through electrical signal processing (such as amplification and filtering), it eliminates ambient light interference and signal noise, generating a stable detection electrical signal. Subsequently, the detection electrical signal is transmitted to the control unit through the conducting switching unit, and the control unit generates the corresponding detection result based on the detection electrical signal.

[0028] When the multi-mode composite photoelectric sensor circuit operates as the transmitter of a through-beam photoelectric sensor, only the light emitting unit needs to participate independently in the functional implementation. Specifically, the mode switching unit outputs a second switching signal to the control unit, and the control unit outputs a second control signal. On the one hand, it drives the light emitting unit to emit a second light signal to the externally matched through-beam photoelectric sensor receiver (the power and transmission distance of the second light signal are adapted to the requirements of the through-beam photoelectric scenario). On the other hand, it controls the switching unit to disconnect the signal transmission path between the control unit and the light receiving unit, so that the light receiving unit is in an idle state, avoiding the generation of invalid electrical signals after receiving external signals that interfere with the control unit logic. At this time, the light emitting unit continuously sends the second light signal to the externally matched through-beam photoelectric sensor receiver, so that the matched through-beam photoelectric sensor receiver can receive the second light signal and complete the object occlusion judgment and detection result generation.

[0029] When the multi-mode composite photoelectric sensor circuit operates as the receiver of a through-beam photoelectric sensor, only the light receiving unit needs to participate in the function independently. Specifically, the mode switching unit outputs a third switching signal to the control unit, and the control unit outputs a third control signal. On the one hand, it disables the light emission function of the light emitting unit to prevent the light signal emitted by it from interfering with the light signal received by the externally matched through-beam photoelectric sensor transmitter. On the other hand, it controls the switching unit to conduct the signal transmission path between the control unit and the light receiving unit. At this time, the light receiving unit focuses on receiving the light signal emitted by the matched through-beam photoelectric sensor transmitter, converts it into an electrical signal, processes it to generate a detection electrical signal, and then transmits it to the control unit through the conducting switching unit. The control unit generates the corresponding detection result based on the detection electrical signal.

[0030] It is understood that in the embodiments of this application, when the multi-mode composite photoelectric sensor circuit works as the transmitter or receiver of the through-beam photoelectric sensor, there is no restriction on the specific type of the other target through-beam photoelectric sensor that works in cooperation. The target through-beam photoelectric sensor can be a multi-mode composite photoelectric sensor with the same circuit structure as this application, or it can be a traditional single-function through-beam photoelectric sensor. As long as the optical signal receiving / transmitting parameters of the target through-beam photoelectric sensor match the optical signal transmitting / receiving parameters of the circuit of this application, the through-beam detection function can be realized.

[0031] The multi-mode composite photoelectric sensor circuit provided in this application generates different first, second, and third switching signals through a mode switching unit. The control unit outputs a first, second, and third control signal respectively based on these different switching signals, thereby controlling the light emitting unit to emit a first or second light signal, or disabling its light emission function. Simultaneously, a switching unit connects the signal transmission path between the light receiving unit and the control unit under the action of the first or third control signal, and disconnects the signal transmission path under the action of the second control signal. This allows the light receiving unit to receive external feedback light signals and convert them into detection electrical signals for the control unit to generate detection results. This achieves reliable switching of a single photoelectric sensor between diffuse reflection mode, through-beam emitting mode, and through-beam receiving mode. This technical solution solves the problems of high cost, large inventory pressure, complex installation, and poor flexibility caused by the need to produce and use multiple independent products for different detection modes in existing photoelectric sensors. It significantly reduces production and procurement costs, reduces inventory, simplifies installation and maintenance, improves sensor versatility and adaptability, and ensures accurate and reliable signal transmission paths in each mode.

[0032] In some embodiments, Figure 2 A schematic diagram of the structure of the mode switching unit provided in an embodiment of this application is shown, as follows: Figure 2 As shown in the embodiment of this application, the mode switching unit includes a first variable resistor RV1 and a first capacitor C1.

[0033] The first terminal of the first variable resistor RV1 is connected to a preset first power supply, and the second terminal is grounded. The resistance adjustment terminal is connected to both the control unit and the first terminal of the first capacitor C1. The second terminal of the first capacitor C1 is grounded. The first power supply powers the mode switching unit. When the resistance of the first variable resistor RV1 is adjusted to a preset first resistance value, it generates a first switching signal and outputs it to the control unit. When the resistance of the first variable resistor RV1 is adjusted to a preset second resistance value, it generates a second switching signal and outputs it to the control unit. When the resistance of the first variable resistor RV1 is adjusted to a preset third resistance value, it generates a third switching signal and outputs it to the control unit. Optionally, the mode switching unit changes the voltage distribution of the RC circuit formed by the first variable resistor RV1 and the first capacitor C1 by adjusting the resistance value, thereby generating first, second, and third switching signals with different voltages at the control unit. After detecting the switching signals with different voltages, the control unit identifies the switching requirement based on the voltage difference and outputs corresponding first, second, and third control signals, thereby driving the optical emitting unit, optical receiving unit, and switching unit to achieve the corresponding operating states.

[0034] In practical applications, the first variable resistor RV1 can be physically adjusted by means of a knob, potentiometer, or digitally adjustable resistor, or its resistance value can be adjusted by an external control circuit to generate the required voltage switching signal, making the mode switching process stable and reliable, and meeting the response accuracy and switching speed requirements of different detection modes.

[0035] In one implementation, the first power supply is used to provide a 5V voltage to the mode switching unit to power the mode switching unit.

[0036] It should be clarified that the power supply voltage required by the mode switching unit should be selected according to the actual design of the sensor circuit, rather than being limited to 5V.

[0037] In some embodiments of this application, in the mode switching unit, the adjustable preset first resistance value is half of the maximum resistance value of the first variable resistor RV1, the preset second resistance value is the maximum resistance value of the variable resistor, and the preset third resistance value is the minimum resistance value of the variable resistor. Optionally, the user can change the resistance value of the first variable resistor RV1 by adjusting its adjustment terminal, thereby generating a first switching signal, a second switching signal, or a third switching signal and outputting it to the control unit so that the control unit can identify different mode switching requirements.

[0038] In one implementation, when the first power supply provides 5V to the mode switching unit, without considering errors, the voltage corresponding to the maximum resistance of the first variable resistor RV1 is 5V, the voltage corresponding to the minimum resistance of the first variable resistor RV1 is 0V, and the voltage corresponding to half of the maximum resistance of the first variable resistor RV1 is 2.5V. That is, at this time, the voltage of the first switching signal is 2.5V, the voltage of the second switching signal is 5V, and the voltage of the third switching signal is 0V.

[0039] It should be clarified that, in the embodiments of this application, the first switching signal, the second switching signal, and the third switching signal are not limited to strictly corresponding to the specific resistance value or precise voltage value of the first variable resistor. The voltage range of the switching signal can be adjusted according to the actual application requirements and system design, as long as the control unit can accurately identify different mode switching states.

[0040] In some embodiments, Figure 3 A schematic diagram of the structure of the optical emitting unit provided in an embodiment of this application is shown, as follows: Figure 3 As shown in the embodiment of this application, the light emitting unit includes a first resistor R1, a second resistor R2, a third resistor R3, a second capacitor C2, a light-emitting diode D1, and a first transistor Q1.

[0041] The first end of the first resistor R1 is connected to the control unit to receive the first, second, or third control signal output by the control unit, and the second end is connected to the control terminal of the first transistor Q1; the first end of the second resistor R2 is grounded, and the second end is connected to the first terminal of the first transistor Q1; the anode of the light-emitting diode D1 is connected to the first end of the third resistor R3 and the first end of the second capacitor C2, respectively, and the cathode is connected to the second terminal of the first transistor Q1; the second end of the third resistor R3 is used to connect to a preset second power supply, and the second end of the second capacitor C2 is grounded; the second power supply is used to power the light-emitting unit; wherein, the first transistor Q1 receives the first control signal to turn on to control the light-emitting diode D1 to emit the first light signal, receives the second control signal to turn on to control the light-emitting diode D1 to emit the second light signal, and receives the third control signal to turn off to control the light-emitting diode D1 to disable its light-emitting function.

[0042] Optionally, during operation, different control signals output by the control unit are applied to the control terminal of the first transistor Q1 via the first resistor R1, thereby changing the transistor's conduction state and controlling the light emission of the light-emitting diode D1. When the control signal is the first control signal, the first transistor Q1 is turned on, and the light-emitting diode D1 emits a first light signal, which can be used to detect reflected light or obstruction from a target object. When the control signal is the second control signal, the first transistor Q1 is turned on, and the light-emitting diode D1 emits a second light signal, which can be used to form a beam path to detect the passage of an object. When the control signal is the third control signal, the first transistor Q1 is turned off, and the light-emitting diode D1 stops emitting light, thus avoiding light signal interference and saving energy. During this process, the second resistor R2 and the third resistor R3 are used to limit the current of the first transistor Q1 and the light-emitting diode D1 to ensure stable light intensity, and the second capacitor C2 is used to suppress transient interference from the power supply and signal, ensuring the accuracy and reliability of the light signal emitted by the light-emitting diode D1. Through the above design, the light emitting unit can flexibly switch the light emission state according to different control signals, thereby realizing the multi-mode composite detection function.

[0043] Understandably, the specific resistance, capacitance, and model of each resistor, capacitor, and transistor in the light emitting unit can be selected and designed according to the required luminous intensity, response speed, and supply voltage of the light emitting unit to meet the requirements of different application scenarios. The first transistor can be a conventional NPN or PNP transistor, the light-emitting diode can be an infrared or visible light LED, and the second power supply voltage can be configured according to the operating voltage and current characteristics of the LED.

[0044] In one implementation, the first transistor is an NPN transistor.

[0045] In one implementation, the second power supply is used to provide 24V voltage to the light emitting unit to power it.

[0046] It should be clarified that the power supply voltage required for the optical emitting unit should be selected according to the actual design of the sensor circuit, rather than being limited to 24V.

[0047] In some embodiments, Figure 4 A schematic diagram of the structure of the switching unit provided in an embodiment of this application is shown, as follows: Figure 4 As shown in the embodiment of this application, the switching unit includes an analog switch SW and a third capacitor C3.

[0048] The input terminal Z of analog switch S2 is connected to the optical receiving unit to receive the detection electrical signal, and the output terminal Y is connected to the control unit to output the detection electrical signal to the control unit. The enable terminal E is connected to the control unit to receive the first, second, or third control signal output by the control unit. The power supply terminal VCC is used to connect to a preset first power supply, and the ground terminal GND is used for grounding. The power supply terminal VCC and the ground terminal GND are also connected through a third capacitor C3. The first power supply is used to power analog switch SW. Analog switch SW receives the first or third control signal to turn on the signal transmission path between the control unit and the optical receiving unit, and receives the second control signal to turn off the signal transmission path between the control unit and the optical receiving unit. Optionally, the control unit can change the conduction state of the analog switch by outputting different control signals to the enable terminal of analog switch SW, thereby achieving flexible switching of the signal transmission path between the optical receiving unit and the control unit. When the first or third control signal is received, the analog switch SW is turned on, allowing the detection electrical signal received by the optical receiving unit to be smoothly transmitted to the control unit. This ensures that the control unit can promptly acquire the optical signal information of the target object and perform subsequent processing. When the second control signal is received, the analog switch SW is turned off, cutting off the signal path between the optical receiving unit and the control unit, thus preventing interference to the signal at the optical transmitting end in through-beam mode. During this process, the third capacitor C3 is used to suppress transient interference in the power supply and signal, stabilize the working state of the analog switch SW, and ensure that the signal does not change abruptly or be lost during switching. Through this design, the analog switch SW can accurately and quickly switch between on and off states according to the control signal, thereby ensuring the reliability of signal transmission and detection accuracy of the multi-mode composite photoelectric sensor in different working modes.

[0049] In one implementation, the first power supply is used to provide a 5V voltage to the switching unit to power the switching unit.

[0050] It should be clarified that the power supply voltage required for the switching unit should be selected according to the actual design of the sensor circuit, rather than being limited to 5V.

[0051] In some embodiments, Figure 5 A schematic diagram of the structure of the optical receiving unit provided in an embodiment of this application is shown, as follows: Figure 5 As shown in the embodiment of this application, the optical receiving unit includes a photodiode PD1, an operational amplifier U1, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, a fourth capacitor C4, a fifth capacitor C5, a sixth capacitor C6, a seventh capacitor C7, and an eighth capacitor C8. The anode of photodiode PD1 is connected to the inverting input of operational amplifier U1 via resistor R4 and capacitor C4, and grounded via resistor R5. The cathode is connected to a preset first power supply via resistor R6, and grounded via capacitor C5. The first power supply provides a reverse bias voltage for photodiode PD1. The non-inverting input of operational amplifier U1 is connected to the first power supply via resistor R7, and grounded via resistor R8 and capacitor C6 in parallel. The first power supply provides a reference voltage for the non-inverting input of operational amplifier U1. The inverting input of operational amplifier U1 is also connected to the output of operational amplifier U1 via resistor R9 and capacitor C7 in parallel. The output of operational amplifier U1 is also connected to the switching unit via resistor R10, and grounded via capacitor C8.

[0052] Optionally, in this embodiment, when the optical receiving unit receives an externally fed-back optical signal, the photodiode PD1 converts the optical signal into a weak current signal. This current signal is then converted into a weak voltage signal by the fifth resistor R5, and then filtered and limited by the fourth resistor R4 and the fourth capacitor C4 to improve signal stability and anti-interference capability. Subsequently, this voltage signal enters the inverting input terminal of the operational amplifier U1, and after being amplified by the operational amplifier U1, it is output as a detection electrical signal that can be recognized by the control unit. The seventh resistor R7, the eighth resistor R8, and the sixth capacitor C6 form the reference circuit of the operational amplifier U1 to ensure that the input terminal of the operational amplifier U1 has a stable reference voltage, thereby improving the accuracy of the amplified signal. The ninth resistor R9 and the seventh capacitor C7 form a negative feedback loop with the output terminal of the operational amplifier U1 to adjust the gain and suppress high-frequency noise. The tenth resistor R10 and the eighth capacitor C8 form an RC filter to transmit the detection electrical signal output by the operational amplifier U1 to the switching unit after RC filtering.

[0053] In one implementation, the first power supply is used to provide a 5V voltage to the optical receiving unit.

[0054] It should be clarified that the reverse bias voltage required for the optical receiving unit should be selected according to the actual design of the sensor circuit, rather than being limited to 5V.

[0055] In one implementation, the operational amplifier of the optical receiving unit also has a power supply terminal and a ground terminal. The power supply terminal is connected to a first power supply and grounded through a filter capacitor, while the ground terminal is directly grounded.

[0056] In some embodiments, the multi-mode composite photoelectric sensor circuit provided in this application includes a control unit (MCU). The microcontroller is configured to receive a first switching signal and output a first pulse signal and a first enable signal to the light emitting unit and the switching unit, respectively; receive a second switching signal and output a second pulse signal and a second enable signal to the light emitting unit and the switching unit, respectively; and receive a third switching signal and output a third pulse signal and a first enable signal to the light emitting unit and the switching unit, respectively.

[0057] The first pulse signal is used to control the optical emitting unit to emit a first optical signal, the second pulse signal is used to control the optical emitting unit to disable its light emission function, the third pulse signal is used to control the optical emitting unit to emit a third optical signal, the first enable signal is used to connect the signal transmission path between the control unit and the optical receiving unit, and the second enable signal is used to disconnect the signal transmission path between the control unit and the optical receiving unit.

[0058] The first control signal includes a first pulse signal and a first enable signal; the second control signal includes a second pulse signal and a second enable signal; and the third control signal includes a third pulse signal and a first enable signal.

[0059] Optionally, in this embodiment, the control unit receives a first switching signal, a second switching signal, and a third switching signal from the mode switching unit, and outputs corresponding pulse signals and enable signals to the light emitting unit and the switching unit, respectively. Specifically, the first switching signal triggers the control unit to output a first pulse signal to control the light emitting unit to emit a first light signal, and simultaneously outputs a first enable signal to turn on the switching unit, realizing signal transmission between the control unit and the light receiving unit, thereby configuring the diffuse reflection photoelectric sensor; the second switching signal triggers the control unit to output a second pulse signal to control the light emitting unit to disable its light emission function, and simultaneously outputs a second enable signal to turn off the switching unit, cutting off signal transmission between the control unit and the light receiving unit, thereby configuring the through-beam photoelectric sensor transmitter; the third switching signal triggers the control unit to output a third pulse signal to control the light emitting unit to emit a third light signal, and simultaneously outputs a first enable signal to turn on the switching unit, ensuring that the signal transmission path between the control unit and the light receiving unit remains open, thereby configuring the through-beam photoelectric sensor receiver.

[0060] In some embodiments, Figure 6 This illustration shows another module diagram of the multi-mode composite photoelectric sensor circuit provided in an embodiment of this application. Figure 7A schematic diagram of the structure of the output unit provided in an embodiment of this application is shown, as follows: Figure 6 and Figure 7 As shown, the multi-mode composite photoelectric sensor circuit provided in this application embodiment further includes an output unit, which includes an eleventh resistor R11, a twelfth resistor R12, a second transistor Q2, a second variable resistor RV2, and a fuse F1. The first end of the eleventh resistor R11 is connected to the control unit to receive the level signal output based on the detection result, and the second end is connected to the control terminal of the second transistor Q2. The emitter of the second transistor Q2 is grounded, and the collector is grounded through the second variable resistor RV2, and the output terminal of the output unit outputs a switching signal. The emitter of the second transistor Q2 is grounded through the fuse F1 to protect the output unit in case of abnormal current. The control unit is also used to output a level signal based on the detection result. When the control unit outputs a high-level signal, the second transistor Q2 is turned on to output a low-level switching signal at the output terminal; when the control unit outputs a low-level signal, the second transistor Q2 is turned off to output a high-impedance state at the output terminal.

[0061] Optionally, this embodiment of the application achieves reliable feedback and signal conversion of the control unit's detection results through the coordinated operation of each device in the output unit. Specifically, the eleventh resistor R11 is used to limit the drive current of the control unit's output level signal, preventing it from directly acting on the second transistor Q2 and causing overload problems; the second transistor Q2 is turned on or off according to the level signal output by the control unit, converting the high and low level signals of the control unit into switching signals at the output terminal, thereby driving subsequent circuits or external loads; the second variable resistor RV2 is used to adjust the conduction characteristics of the output terminal, so that the output signal meets the current carrying requirements under different application scenarios; the fuse F1 is used to provide overcurrent protection when abnormal current occurs at the output terminal, avoiding damage to the output unit and connected loads.

[0062] Understandably, the second transistor Q2 can be a conventional NPN or PNP transistor.

[0063] In one implementation, the second transistor Q2 is an NPN transistor.

[0064] In this embodiment, the output unit can output a switching signal according to the detection result of the control unit, and also has current regulation and overcurrent protection functions, which improves the overall reliability, safety and applicability of the multi-mode composite photoelectric sensor circuit.

[0065] It is understood that in the embodiments of this application, the first power supply required by the analog switching unit, the optical receiving unit, the switching unit, and the control unit is the same power supply. The purpose of the embodiments of this application is not to improve the power supply direction of the sensor circuit, therefore, the power supply part will not be described in detail here, and the power supply part of the sensor circuit is designed with conventional technical means in the art. For example, in the sensor circuit, the second power supply can be designed as an external high-voltage power supply such as 24V, and the first power supply is a voltage conversion module used to convert the external high-voltage power supply into a low voltage such as 5V to provide power to the various functional modules of the sensor circuit.

[0066] The above description, in conjunction with specific embodiments, provides a further detailed explanation of this application and should not be construed as limiting the specific implementation of this application to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of this application, and all such modifications and substitutions should be considered within the scope of protection of this application.

Claims

1. A multi-mode composite photoelectric sensor circuit, characterized in that, include: A mode switching unit is used to generate a first switching signal, a second switching signal, or a third switching signal; The control unit, connected to the mode switching unit, is used to output a first control signal according to the first switching signal, output a second control signal according to the second switching signal, and output a third control signal according to the third switching signal; An optical emitting unit, connected to the control unit, is used to receive the first control signal and emit a first optical signal; Upon receiving the second control signal, emit a second light signal; upon receiving the third control signal, disable the light emission function. A switching unit and an optical receiving unit are provided. The switching unit is connected to the control unit and the optical receiving unit respectively. It is used to receive the first control signal or the third control signal to turn on the signal transmission path of the control unit and the optical receiving unit, and to receive the second control signal to disconnect the signal transmission path of the control unit and the optical receiving unit. The optical receiving unit is used to receive optical signals fed back from the outside, convert the optical signals into electrical signals, process the electrical signals to generate detection electrical signals, and output them to the control unit so that the control unit outputs detection results. Wherein, the first switching signal is used to control the multi-mode composite photoelectric sensor circuit to work as a diffuse reflection photoelectric sensor, the second switching signal is used to control the multi-mode composite photoelectric sensor circuit to work as the transmitter of a through-beam photoelectric sensor, and the third switching signal is used to control the multi-mode composite photoelectric sensor circuit to work as the receiver of a through-beam photoelectric sensor.

2. The multi-mode composite photoelectric sensor circuit as described in claim 1, characterized in that, The mode switching unit includes a first variable resistor and a first capacitor; The first terminal of the first variable resistor is connected to a preset first power supply, the second terminal is grounded, and the resistance adjustment terminal is connected to the control unit and the first terminal of the first capacitor respectively; the second terminal of the first capacitor is grounded; the first power supply is used to power the mode switching unit. Specifically, when the resistance value of the first variable resistor is adjusted to a preset first resistance value, the first variable resistor generates the first switching signal and outputs it to the control unit; when the resistance value of the first variable resistor is adjusted to a preset second resistance value, the first variable resistor generates the second switching signal and outputs it to the control unit; when the resistance value of the first variable resistor is adjusted to a preset third resistance value, the first variable resistor generates the third switching signal and outputs it to the control unit.

3. The multi-mode composite photoelectric sensor circuit as described in claim 2, characterized in that, The preset first resistance value is half of the maximum resistance value of the first variable resistor, the preset second resistance value is the maximum resistance value of the first variable resistor, and the preset third resistance value is the minimum resistance value of the first variable resistor.

4. The multi-mode composite photoelectric sensor circuit as described in claim 1, characterized in that, The light emitting unit includes a first resistor, a second resistor, a third resistor, a second capacitor, a light-emitting diode, and a first transistor; The first end of the first resistor is connected to the control unit to receive the first control signal, the second control signal, or the third control signal output by the control unit, and the second end is connected to the control terminal of the first transistor. The first terminal of the second resistor is grounded, and the second terminal is connected to the first terminal of the first transistor. The anode of the light-emitting diode is connected to the first terminal of the third resistor and the first terminal of the second capacitor, respectively, and the cathode is connected to the second terminal of the first transistor; The second end of the third resistor is used to connect to a preset second power supply, and the second end of the second capacitor is grounded; the second power supply is used to power the light emitting unit. The first transistor receives the first control signal to turn on and control the light-emitting diode to emit a first light signal, receives the second control signal to turn on and control the light-emitting diode to emit a second light signal, and receives the third control signal to turn off and control the light-emitting diode to disable its light-emitting function.

5. The multi-mode composite photoelectric sensor circuit as described in claim 1, characterized in that, The switching unit includes an analog switch and a third capacitor; The input terminal of the analog switch is connected to the optical receiving unit to receive the detection electrical signal, and the output terminal is connected to the control unit to output the detection electrical signal to the control unit. The enable terminal is connected to the control unit to receive the first control signal, the second control signal, or the third control signal output by the control unit. The power supply terminal is used to connect to a preset first power supply, and the ground terminal is used for grounding. The power supply terminal and the ground terminal are also connected through the third capacitor. The first power supply is used to power the analog switch. The analog switch receives the first control signal or the third control signal to connect the signal transmission path between the control unit and the optical receiving unit, and receives the second control signal to disconnect the signal transmission path between the control unit and the optical receiving unit.

6. The multi-mode composite photoelectric sensor circuit as described in claim 1, characterized in that, The optical receiving unit includes a photodiode, an operational amplifier, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor, and an eighth capacitor; The anode of the photodiode is connected to the inverting input of the operational amplifier through the fourth resistor and the fourth capacitor, and is grounded through the fifth resistor. The cathode is connected to a preset first power supply through the sixth resistor, and is grounded through the fifth capacitor. The first power supply is used to provide a reverse bias voltage for the photodiode. The non-inverting input terminal of the operational amplifier is connected to the first power supply through the seventh resistor and grounded through the eighth resistor and the sixth capacitor connected in parallel; the first power supply is used to provide a reference voltage for the non-inverting input terminal of the operational amplifier. The inverting input terminal of the operational amplifier is also connected to the output terminal of the operational amplifier through a ninth resistor and a seventh capacitor connected in parallel. The output of the operational amplifier is also connected to the switching unit through the tenth resistor and grounded through the eighth capacitor.

7. The multi-mode composite photoelectric sensor circuit as described in claim 1, characterized in that, The control unit includes a microcontroller; The microcontroller is configured to receive the first switching signal and output a first pulse signal and a first enable signal to the optical emitting unit and the switching unit respectively; receive the second switching signal and output a second pulse signal and a second enable signal to the optical emitting unit and the switching unit respectively; receive the third switching signal and output a third pulse signal and the first enable signal to the optical emitting unit and the switching unit respectively. Wherein, the first pulse signal is used to control the optical emitting unit to emit the first optical signal, the second pulse signal is used to control the optical emitting unit to emit the second optical signal, the third pulse signal is used to control the optical emitting unit to disable the light emission function, the first enable signal is used to connect the signal transmission path between the control unit and the optical receiving unit, and the second enable signal is used to disconnect the signal transmission path between the control unit and the optical receiving unit; Wherein, the first control signal includes the first pulse signal and the first enable signal; the second control signal includes the second pulse signal and the second enable signal; and the third control signal includes the third pulse signal and the first enable signal.

8. The multi-mode composite photoelectric sensor circuit as described in claim 1, characterized in that, It also includes an output unit, which includes an eleventh resistor, a twelfth resistor, a second transistor, a second variable resistor, and a fuse; The first end of the eleventh resistor is connected to the control unit to receive the level signal output according to the detection result, and the second end is connected to the control terminal of the second transistor. The emitter of the second transistor is grounded, the collector is grounded through the second variable resistor, and the output terminal of the output unit outputs a switching signal; The emitter of the second transistor is grounded through the fuse to protect the output unit in case of abnormal current. The control unit is further configured to output a level signal based on the detection result. When the control unit outputs a high-level signal, the second transistor is turned on to output a low-level switching signal at the output terminal; when the control unit outputs a low-level signal, the second transistor is turned off to output a high-impedance state at the output terminal.

Images