A safety light curtain

Abstract

The utility model relates to safe detection field discloses a kind of safety light curtain, it includes: including the emitter for emitting infrared signal and the receiver for receiving infrared signal, wherein, receiver includes: first receiving control module, second receiving control module, first output module, second output module and receiving signal processing module;Receiving signal processing module further includes: signal receiving circuit, first signal amplification circuit, second signal amplification circuit and receiving signal processing circuit, signal receiving circuit is connected with first receiving control module;First signal amplification circuit is connected with signal receiving circuit and first receiving control module respectively;Second signal amplification circuit is connected with signal receiving circuit and second receiving control module respectively;Receiving signal processing circuit is connected with signal receiving circuit and first receiving control module respectively, and this safety light curtain can improve safety output guarantee, security and reliability are high by double output, double system.

Description

Technical Field

[0001] This utility model relates to the field of detection technology, and in particular to a safety light curtain. Background Technology

[0002] Light curtain sensors are now widely used in many fields, especially those using infrared light sources. These sensors are widely adopted due to their advantages such as resistance to ambient light interference and no impact on human vision. While these sensors generally work without problems in general applications, in many safety fields, such as those protecting human limbs and lives, a safe, reliable, and stable light curtain sensor is required. Even if the sensor itself is damaged or subjected to severe environmental interference, it should not stop working or malfunction, thus preventing any harm to human limbs or lives.

[0003] A safety light curtain consists of an infrared transmitter and an infrared receiver, installed on both sides of a platform screen door, elevator door, equipment door, etc. The infrared transmitter emits an infrared detection beam, and the infrared receiver receives the signal. When an object obstructs the light, the infrared receiver cannot detect the beam signal emitted by the transmitter, and this information is fed back to the control unit. The control unit then outputs a control signal to perform actions such as reversing the closing platform screen door to open it.

[0004] Currently, most light curtains on the market are Level 2, lacking reliable protection and self-test circuits. Furthermore, they are all single-output, making them low-reliability light curtain sensors. If a fault occurs and the output is not promptly shut off and the fault indicator is not displayed, it can cause significant harm to the user. Therefore, improving the reliability and safety of light curtain sensors in hazardous environments has become a key research focus. Utility Model Content

[0005] This invention provides a safety light curtain that can improve safety output protection through dual output and dual system, resulting in high safety and reliability.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: providing a safety light curtain, including a transmitter for emitting infrared signals and a receiver for receiving the infrared signals, wherein the receiver includes:

[0007] First receiving control module;

[0008] A second receiving control module is connected to the first receiving control module.

[0009] A first output module, which is connected to the first receiving control module;

[0010] The second output module is connected to the second receiving control module.

[0011] The receiving signal processing module further includes:

[0012] A signal receiving circuit, wherein the signal receiving circuit is connected to the first receiving control module;

[0013] A first signal amplification circuit is connected to the signal receiving circuit and the first receiving control module, respectively.

[0014] The second signal amplification circuit is connected to the signal receiving circuit and the second receiving control module, respectively.

[0015] A receiving signal processing circuit is provided, which is connected to both the signal receiving circuit and the first receiving control module.

[0016] According to one embodiment of the present invention, the receiver further includes:

[0017] A first output detection module is connected to both the first output module and the first receiving control module.

[0018] The second output detection module is connected to both the second output module and the second receiving control module.

[0019] According to one embodiment of the present invention, the receiver further includes: a first indication module, which is connected to the first receiving control module and includes: a first light energy indication submodule, a first output status indication submodule, and a first fault indication submodule.

[0020] According to one embodiment of the present invention, the receiver further includes:

[0021] A first power supply module, which is connected to the first receiving control module;

[0022] The second power supply module is connected to the second receiving control module.

[0023] According to one embodiment of the present invention, the transmitter includes:

[0024] Launch control module;

[0025] A transmission signal processing module, which is connected to the transmission control module;

[0026] The second indicator module, which is connected to the transmission control module, includes: a second optical energy indicator submodule, a second output status indicator submodule, and a second fault indicator submodule.

[0027] According to one embodiment of the present invention, the receiver further includes a first communication module connected to the first receiving control module; the transmitter further includes a second communication module connected to the transmitting control module, wherein the first communication module and the second communication module establish a communication connection.

[0028] According to one embodiment of the present invention, the transmitter further includes an auxiliary output module connected to the transmission control module.

[0029] According to one embodiment of the present invention, the transmitter further includes an external device monitoring module connected to the transmission control module.

[0030] According to one embodiment of the present invention, the transmitter further includes a third power supply module connected to the transmission control module.

[0031] According to one embodiment of the present invention, the transmitting signal processing module further includes:

[0032] A signal transmitting circuit, which is connected to the transmitting control module;

[0033] A signal processing circuit is provided, which is connected to both the signal transmitting circuit and the transmission control module.

[0034] The beneficial effects of this utility model are as follows: A safety light curtain includes a transmitter for emitting infrared signals and a receiver for receiving the infrared signals. The receiver includes a first receiving control module, a second receiving control module, a first output module, a second output module, and a receiving signal processing module. The second receiving control module is connected to the first receiving control module. The first output module is connected to the first receiving control module. The receiving signal processing module further includes a signal receiving circuit, a first signal amplification circuit, a second signal amplification circuit, and a receiving signal processing circuit. The signal receiving circuit is connected to the first receiving control module. The first signal amplification circuit is connected to both the signal receiving circuit and the first receiving control module. The second signal amplification circuit is connected to both the signal receiving circuit and the second receiving control module. The receiving signal processing circuit is connected to both the signal receiving circuit and the first receiving control module. This safety light curtain, through dual outputs and a dual system, can improve safety output protection, resulting in high safety and reliability. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the architecture of a safety light curtain according to an embodiment of the present invention;

[0036] Figure 2 This is a schematic diagram of the architecture of a safety light curtain according to another embodiment of the present invention;

[0037] Figure 3 This is a schematic diagram of the architecture of a safety light curtain according to another embodiment of the present invention;

[0038] Figure 4 This is a schematic diagram of the architecture of a safety light curtain according to another embodiment of the present invention;

[0039] Figure 5 This is a schematic diagram of the architecture of a safety light curtain according to another embodiment of the present invention;

[0040] Figure 6 This is a schematic diagram of the architecture of a safety light curtain according to another embodiment of the present invention;

[0041] Figure 7 This is a schematic diagram of the architecture of a safety light curtain according to another embodiment of the present invention;

[0042] Figure 8 This is a schematic diagram of the architecture of the signal transmission processing module in a safety light curtain according to an embodiment of the present invention;

[0043] Figure 9 This is a schematic diagram of the structure of the first power module and the second power module according to an embodiment of the present invention;

[0044] Figure 10 This is a schematic diagram of the structure of the first receiving control module according to an embodiment of the present invention;

[0045] Figure 11 This is a schematic diagram of the structure of the second receiving control module according to an embodiment of the present invention;

[0046] Figure 12 This is a schematic diagram of the structure of a launch control module according to an embodiment of the present invention;

[0047] Figure 13 This is a schematic diagram of the structure of the first communication module and the second communication module according to an embodiment of the present invention;

[0048] Figure 14 This is a schematic diagram of the signal transmitting circuit according to an embodiment of the present invention;

[0049] Figure 15 This is a schematic diagram of the structure of a transmission signal processing circuit according to an embodiment of the present invention;

[0050] Figure 16 This is a schematic diagram of the structure of a signal receiving circuit according to an embodiment of the present invention;

[0051] Figure 17This is a schematic diagram of the receiving signal processing circuit according to an embodiment of the present invention;

[0052] Figure 18 This is a schematic diagram of the structure of a first signal amplification circuit according to an embodiment of the present invention;

[0053] Figure 19 This is a schematic diagram of the structure of the second signal amplification circuit according to an embodiment of the present invention;

[0054] Figure 20 This is a schematic diagram of the structure of the first output module and the second output module according to an embodiment of the present invention;

[0055] Figure 21 This is a schematic diagram of the structure of the first output detection module and the second output detection module according to an embodiment of the present invention;

[0056] Figure 22 This is a schematic diagram of the structure of the first indicator module and the second indicator module according to an embodiment of the present invention;

[0057] Figure 23 This is a schematic diagram of the structure of an auxiliary output module according to an embodiment of the present invention;

[0058] Figure 24 This is a schematic diagram of the structure of an external device monitoring module according to an embodiment of the present invention. Detailed Implementation

[0059] The technical solutions of the present utility model 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 the present utility model, and not all of them. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0060] The terms "first," "second," and "third" in this utility model are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first," "second," or "third" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified. All directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of this utility model are only used to explain the relative positional relationships and movement of the components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.

[0061] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the present invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0062] Figure 1 This is a schematic diagram of the architecture of a safety light curtain according to an embodiment of this utility model. Figure 1 As shown, the safety light curtain 100 includes a transmitter 10 for emitting infrared signals and a receiver 20 for receiving infrared signals. The receiver 20 includes: a first receiving control module 201, a second receiving control module 202, a receiving signal processing module 203, a first output module 204, and a second output module 205. The second receiving control module 202 is connected to the first receiving control module 201; the receiving signal processing module 203 is connected to both the first receiving control module 201 and the second receiving control module 202; the first output module 204 is connected to the first receiving control module 201; and the second output module 205 is connected to the second receiving control module 202. The receiving signal processing module 203 further includes: a signal receiving circuit 2031, a first signal amplification circuit 2032, a second signal amplification circuit 2033, and a receiving signal processing circuit 2034. The signal receiving circuit 2031 is connected to the first receiving control module 201 and is used to receive infrared signals emitted by the transmitter 10. The first signal amplification circuit 2032 is connected to both the signal receiving circuit 2031 and the first receiving control module 201. The second signal amplification circuit 2033 is connected to both the signal receiving circuit 2031 and the second receiving control module 202. The receiving signal processing circuit 2034 is connected to both the signal receiving circuit 2031 and the first receiving control module 201. In this embodiment, the first signal amplification circuit 2032 and the second signal amplification circuit 2033 may include operational amplifiers (op-amps). The op-amps can amplify and filter the received signals generated by the signal receiving circuits and transmit the received signals to the control module. This embodiment employs dual operational amplifiers. The first signal amplification circuit 2032 supplies the received signal to the first receiving control module 201 for processing, and the second signal amplification circuit 2033 supplies the received signal to the second receiving control module 202 for processing. These two independent signal amplification circuits provide reliable protection for the dual detection system. This safety light curtain enhances safety output protection through dual outputs and a dual system, resulting in high safety and reliability.

[0063] In one feasible implementation, please refer to Figure 2The receiver 20 further includes a first indication module 206, which is connected to the first receiving control module 201. The first indication module 206 includes a first light energy indication submodule 2061, a first output status indication submodule 2062, and a first fault indication submodule 2063. In this embodiment, the first light energy indication submodule 2061 indicates whether the light curtain installation is offset. The first light energy indication submodule 2061 facilitates user installation and use of the safety light curtain 100, improving user experience. The first output status indication submodule 2062 indicates the light transmission and blocking status, the status of communication cables, etc. The first fault indication submodule 2063 indicates internal circuit self-test faults. If an abnormality is detected, the status display can be used to easily locate the fault point and facilitate troubleshooting when a fault occurs. Internal circuit self-test faults include faults occurring in one or more of the first output module 204, the second output module 205, and the receiving signal processing module 203.

[0064] The first output module 204 and the second output module 205 can be NPN outputs or PNP outputs. For example, both the first output module 204 and the second output module 205 are NPN outputs. Alternatively, both the first output module 204 and the second output module 205 are PNP outputs. Another example is where the first output module 204 is an NPN output and the second output module 205 is a PNP output. Yet another example is where the first output module 204 is a PNP output and the second output module 205 is an NPN output.

[0065] The safety light curtain 100 emits infrared signals through the transmitter 10. The receiving signal processing module 203 receives and processes the infrared signals. The first receiving control module 201 receives the processed infrared signals and outputs control signals through the first output module 204. The second receiving control module 202 receives the processed infrared signals and outputs control signals through the second output module 205. The first receiving control module 201 detects the light intensity of the processed infrared signals and indicates whether the light curtain is misaligned through the first light energy indicator submodule 2061. The first receiving control module 201 analyzes the processed infrared signals to determine the light transmission and blocking status and the status of the communication cables, and uses the first output status indicator submodule 2062 to indicate the light transmission and blocking status and the status of the communication cables. If there is an internal circuit self-test fault, the first receiving control module 201 controls the first fault indicator submodule 2063 to indicate the internal circuit self-test fault. This safety light curtain 100 can promptly indicate the installation status, working status, and fault problems, and has high safety and reliability.

[0066] In one feasible implementation, the first light energy indicator submodule 2061, the first output status indicator submodule 2062, and the first fault indicator submodule 2063 can each be equipped with three sets of signal indicator lights; wherein the first output status indicator submodule 2062 and the first fault indicator submodule 2063 can share the three sets of signal indicator lights. The signal indicator lights can be set in groups of four axes so that the user can intuitively see the indicator light indications from the upper, middle, and lower parts of the safety light curtain 100. For example, if the first light energy indicator submodule 2061 includes three sets of signal indicator lights of the same color, and the first output status indicator submodule 2062 and the first fault indicator submodule 2063 can share three sets of signal indicator lights of different colors, then the indication strategy can be implemented according to Tables 1 and 2 below:

[0067] Table 1 shows the indication strategies for the first output status indication submodule 2062 and the first fault indication submodule 2063.

[0068]

[0069] Table 2 shows the indication strategy of the first light energy indicator submodule 2061.

[0070]

[0071] In one feasible implementation, please refer to Figure 3 The receiver 20 further includes a first output detection module 207 and a second output detection module 208. The first output detection module 207 is connected to the first output module 204 and the first receiving control module 201, respectively. The second output detection module 208 is connected to the second output module 205 and the second receiving control module 202, respectively. In this embodiment, the first output detection module 207 performs fault detection on the first output module 204 and feeds it back to the first receiving control module 201. If a circuit fault occurs in the first output module 204, the first receiving control module 201 controls the first fault indication submodule 2063 to indicate an internal circuit self-test fault. The second output detection module 208 performs fault detection on the second output module 205 and feeds it back to the second receiving control module 202. If a circuit fault occurs in the second output module 205, the second receiving control module 202 controls the second fault indication submodule to indicate an internal circuit self-test fault. In this embodiment, the first output module 204 and the second output module 205 of the safety light curtain 100 can output safety signals normally and independently. When one or two outputs fail, they can be detected in time through mutual inspection, and the output can be shut down in time, and the fault can be indicated by the first indicator module 206.

[0072] In one feasible implementation, please refer to Figure 4The receiver 20 further includes a first power module 209 and a second power module 210. The first power module 209 is connected to the first receiving control module 201; the second power module 210 is connected to the second receiving control module 202. The first power module 209 and the second power module 210 may be the same or different. In one feasible embodiment, both the first power module 209 and the second power module 210 adopt power circuits with integrated DC-DC and low-dropout linear regulators to meet the voltage, maximum current, and power requirements of the safety light curtain 100. The dual power modules independently power the two receiving control modules, with separate power distribution. When a problem occurs in the power supply of one power module, the other can still perform the early warning function normally, preventing potential safety hazards.

[0073] In one feasible implementation, please refer to Figure 5 The transmitter 10 includes a transmission control module 101, a transmission signal processing module 102, a second indicator module 103, an auxiliary output module 104, and an external device monitoring module 105. The transmission signal processing module 102 is connected to the transmission control module 101, the second indicator module 103 is connected to the transmission control module 101, the auxiliary output module 104 is connected to the transmission control module 101, and the external device monitoring module 105 is connected to the transmission control module 101. The auxiliary output module 104 outputs the same data as the receiver 20, and its function is to supply power to the relays or alarms of the transmitter 10. The external device monitoring module 105 (EDM) detects malfunctions (contact welding) of external devices controlling dangerous parts of the machine. External devices typically refer to forced shutdown protection devices connected to the safety light curtain 100, such as relays and alarms. Once these external devices exhibit safety hazards, they can be detected and prevented from causing safety problems in a timely manner. For example, if the relay connection point is under high load and high frequency for a long time, oxidation of the surface metal layer of the contact point can cause the connected contacts to stick together, resulting in abnormal output and failure to output the correct signal in time when a danger occurs.

[0074] The second indicator module 103 includes a second light energy indicator submodule 1031, a second output status indicator submodule 1032, and a second fault indicator submodule 1033. In this embodiment, the second light energy indicator submodule 1031 is the same as the first light energy indicator submodule 2061. The second output status indicator submodule 1032 is used to indicate light transmission and blocking states, the status of communication cables, etc. The second fault indicator submodule 1033 is used to indicate internal circuit self-test faults and external device monitoring status. If an abnormality is detected, the status display can be shown through the second fault indicator submodule 1033, which can easily locate the fault point and facilitate troubleshooting when a fault occurs. Internal circuit self-test faults include faults occurring in one or more of the first output module 204, the second output module 205, and the receiving signal processing module 203.

[0075] In one feasible implementation, the second light energy indicator submodule 1031, the second output status indicator submodule 1032, and the second fault indicator submodule 1033 can each be equipped with three sets of signal indicator lights; wherein the second output status indicator submodule 1032 and the second fault indicator submodule 1033 can share the three sets of signal indicator lights. The signal indicator lights can be set in groups of four axes so that the user can visually see the indicator light indications from the upper, middle, and lower parts of the safety light curtain 100. For example, if the second light energy indicator submodule 1031 includes three sets of signal indicator lights of the same color, and the second output status indicator submodule 1032 and the second fault indicator submodule 1033 can share three sets of signal indicator lights of different colors, then the indication strategy can be implemented according to Tables 3 and 4 below:

[0076] Table 3 shows the indication strategies for the second output status indication submodule 1032 and the second fault indication submodule 1033.

[0077]

[0078] Table 4 shows the indication strategy of the second light energy indication submodule 1031.

[0079]

[0080] In one feasible implementation, please refer to Figure 6The receiver 20 further includes a first communication module 211 connected to the first receiving control module 201; the transmitter 10 further includes a second communication module 106 connected to the transmitting control module 101, and the first communication module 211 and the second communication module 106 establish a communication connection. Both the first communication module 211 and the second communication module 106 use RS-485 communication, which ensures the stability of the synchronization signal (differential transmission technology transmits signals, using twisted-pair differential transmission to transmit digital signals, which can improve the transmission rate, reduce crosstalk and interference, and is suitable for long-distance transmission), and can also perform information communication. The main functions of the first communication module 211 and the second communication module 106 are as follows: synchronization of the transmitter 10 and the receiver 20 (such as frequency synchronization, output signal synchronization), fault information synchronization, and optical energy information synchronization.

[0081] In one feasible implementation, please refer to Figure 7 The transmitter 10 also includes a third power module 107 connected to the transmission control module 101. The circuit structure of the third power module 107 may be the same as or different from that of the first power module 209.

[0082] In one feasible implementation, please refer to Figure 8 The transmission signal processing module 102 further includes a signal transmission circuit 1021 and a transmission signal processing circuit 1022. The signal transmission circuit 1021 is connected to the transmission control module 101; the transmission signal processing circuit 1022 is connected to both the signal transmission circuit 1021 and the transmission control module 101. The transmission signal processing circuit 1022 includes a trigger and a decoder.

[0083] For example, the implementation circuits of each module of the safety light curtain 100 are as follows: Figure 9-18 As shown.

[0084] Please see Figure 9 Both the first power module 209 and the second power module 210 adopt power supply circuits with integrated DC-DC and low-dropout linear regulators. These power supply circuits also have functions such as triggering current limiting and short-circuit protection when the input current is too large, thermal shutdown and automatic recovery when the ambient temperature is too high, and power-off protection to protect the output overvoltage of the downstream load when the output voltage exceeds the set voltage value. At the same time, an input power detection circuit is added to the power supply circuit. When the voltage across the Zener diode D3 exceeds the Zener value Vz, the voltage across the resistor R11 reaches 0.7V, thereby turning on the transistor Q1. Under the current limiting effect of the pull-up resistor R9, a trigger signal is given to the first receiving control module 201 and / or the second receiving control module 202. Upon receiving the trigger signal, the first receiving control module 201 and / or the second receiving control module 202 promptly shut down the output, thereby achieving the effect of input overvoltage protection.

[0085] Please see Figure 10 The first receiving control module 201 is used to provide the main frequency signal, RS-485 communication signal, trigger clock signal, analog switch enable pin signal, address signal, indicator light and energy lamp signal, as well as process the first operational amplifier signal and output, etc.

[0086] Please see Figure 11 The second receiving control module 202 is used to process the second operational amplifier signal, communicate with the first receiving control module 201, detect mutual detection signals, and output signals.

[0087] Please see Figure 12 The transmit control module 101 is used to process various information from RS-485 communication, including synchronization, signal fault, energy detection, decoder, trigger signals, output auxiliary output signals, EDM external interrupt control signals, etc.

[0088] Please see Figure 13 Both the first communication module 211 and the second communication module 106 use RS-485 communication.

[0089] The signal processing module 102 includes a signal transmission circuit 1021 (e.g., Figure 14 (as shown) and the transmit signal processing circuit 1022 (as shown) Figure 15 As shown, the signal transmitting circuit 1021 generates a frequency consistent with the main frequency based on the RS-485 communication signal, controls the trigger to select the cascaded decoder, and then the decoder controls the switch through the address signal and the on / off time of the enable pin, generating a rectangular periodic pulse signal with adjustable pulse width and period arranged in sequence. This then controls the PMOS switch to make the infrared LED emit modulated light to the signal receiving circuit. The circuit also includes a PA5_MC14013_QA signal, which is a detection signal used to check whether the decoder and trigger are working properly. There is also a PA8_Light_4059_BACK signal, which checks whether the transmitter 10 is transmitting a normal signal and whether there are any missing signals. This signal can also easily pinpoint the fault location during troubleshooting.

[0090] The signal processing module 203 also includes: a signal receiving circuit 2031 (e.g., Figure 16 As shown), the first signal amplifier circuit 2032 (as shown) Figure 18 (as shown), second signal amplifier circuit 2033 (as shown) Figure 19 (as shown) and the receiving signal processing circuit 2034 (as shown) Figure 17(As shown). The signal receiving circuit 2031 selects the cascaded analog switches through a trigger according to the synchronization frequency. Then, the analog switches control the 8 sets of switch signals through the address signal and the on / off time of the enable pin. The 8 sets of switches, arranged in sequence, receive the infrared light signal from the corresponding open transmitter 10. The signal is then coupled onto a signal line and transmitted to the first signal amplification circuit 2032 and the second signal amplification circuit 2033 for amplification.

[0091] The receiving signal processing circuit 2034 provides a clock signal via PA6_MC14013_CA and a switch signal via PA7_MC14013_DA. Then, the switch signal is sent to the enable pin of the analog switch via HC138_G2A#_low to control the on / off time of the total signal of the analog switch. Simultaneously, address signals are provided via PB13_HC4051_C, PB14_HC4051_B, and PB15_HC4051_A. The opening time of the eight groups of switches controlled by the enable pin is approximately the same as the decoding switching time of transmitter 10, achieving consistency with the transmit / receive timing of transmitter 10 and improving electromagnetic interference immunity. The circuit also includes a PA5_MC14013_QA signal, a detection signal used to check if the multiplexer and triggers are working properly. If not, a fault signal will be issued, and the output and fault display will be shut down promptly.

[0092] Please see Figure 18 The first signal amplification circuit 2032 is equipped with a set of energy detection circuits, which are used to generate signals used by the first optical energy indicator submodule 2061 and the second optical energy indicator submodule 1031.

[0093] Please see Figure 20The first output module 204 and the second output module 205 are commonly used transistor OC output modules. The safety light curtain 100 employs dual outputs: one output is provided by the first receiving control module 201, and the other by the second receiving control module 202. A detection circuit (i.e., the first output detection module 207 and the second output detection module 208) is provided between them. When the first receiving control module 201 experiences an output fault, it is determined that there is a problem with its output circuit. This signal is then transmitted to the second receiving control module 202, which immediately issues a stop output signal, shutting off the output, and the indicator module synchronously indicates the fault. The first output module 204 and the second output module 205 are respectively equipped with a short-circuit protection detection circuit and an output signal monitoring circuit. Short circuit: When the output current is too large, it will drive transistor Q16 or transistor Q17 to conduct (the voltage across the load resistor reaches the transistor's turn-on voltage of 0.7V). Then, the signal is connected to the receiving control module through the pull-up resistor. When the receiving control module detects the signal, it will turn off the output and the indicator light will indicate this. The output will be restored after the signal is sensed again.

[0094] Please see Figure 21 The detection circuit detects the output of OUT_L and OUT_H signals. It detects a high level when the output is high and a low level when the output is low. Then, it transmits the signals PF6_Output_L_check and PF7_Output_H_check to the corresponding receiving control module. The receiving control module compares the output signals PB8_Output_signal_L and PB9_Output_signal_H with PF6_Output_L_check and PF7_Output_H_check to determine whether the output is abnormal.

[0095] The first indicator module 206 and the second indicator module are as follows: Figure 22 As shown.

[0096] Auxiliary output module 104, etc. Figure 23As shown, the auxiliary output module 104 is an open-circuit (OC) output of a non-safety NPN transistor. This auxiliary output module 104 is located in the transmitter 10. When an object blocks the light, the first receiving control module 201 transmits a signal to the transmitting control module 101 via RS-485 communication. The transmitting control module 101 generates corresponding digital signals 0 / 1 to PB0_AUXintput, controlling the 0 / 1 level transition of the AUX Output through an NMOS transistor. This circuit can also include a self-test circuit, PA7_AUX check. This signal monitors the AUX Output signal; a high level indicates a high output level, and a low level indicates a low output level. The transmitting control module 101 monitors and compares the PB0_AUX intput and PA7_AUX check signals in real time. If an abnormal output is detected, a fault message is issued, and the output is paused.

[0097] Please see Figure 24 The external device monitoring module 105 can monitor in real time for contact sticking and response delay faults in the drive relays of the first output module 204 and the second output module 205 while in operation. When one or more of the monitored relays fail, the safety light curtain 100 immediately locks the output and stops working, and the fault can be displayed by indicator lights. The switch signal is connected to the external device monitoring signal, and then, through optocoupler isolation, generates the PA0 / 1_switch_OUT signal, which is transmitted to the transmission control module 101. The transmission control module 101 then issues a judgment signal by determining whether the delay time between the output signal and the EDM signal is within the specified time.

[0098] The principle of the safety light curtain 100 is as follows:

[0099] 1: The first receiving control module 201 of receiver 20 generates a fixed frequency based on an external 16M crystal oscillator, and generates a series of synchronization signals based on the fixed frequency, such as RS-485 synchronization signal, fault output signal, indicator light output signal, decoder address signal, trigger signal, analog switch signal, etc.

[0100] 2: The first communication module 211 and the second communication module 106 transmit the synchronization signal to the transmitter 10 via a transmission line. When the transmitter 10 is properly connected and is the corresponding transmitter model, a handshake signal is transmitted back to the receiver 20 through the first communication module 211 and the second communication module 106, informing the receiver 20 that synchronization is normal. Then, some synchronization frequencies, such as indicator light signals and fault signals, are transmitted, and the transmitter 10 processes these signals.

[0101] 3. After the transmitter control module 101 of transmitter 10 successfully synchronizes, the generated trigger signals PA14_MC14013_CA (clock signal) and PA15_MC14013_DA (data signal) control the operation of the trigger of transmitter 10. Then, an HC138_G2A#_low signal is generated from the trigger, which is consistent with the PA15_MC14013_DA signal. This signal is transmitted to the enable terminal of the decoder, and together with the three address signals PB7_HC138_A, PB6_HC138_B, and PB5_HC138_C, it controls the output of the decoder to generate eight sequentially arranged modulation pulse signals. These signals then drive the infrared LEDs to output infrared modulated light.

[0102] 4. Similarly, after successful synchronization, receiver 20 generates trigger signals PA6_MC14013_CA (clock signal) and PA7_MC14013_DA (data signal) to control the operation of transmitter 10's trigger. Then, the trigger generates an HC138_G2A#_low signal, which is consistent with the PA7_MC14013_DA signal. This signal is transmitted to the enable terminal of the analog switch, and together with the three address signals PB15_HC4051_A, PB14_HC4051_B, and PB13_HC4051_C, controls the output of the analog switch, sequentially opening the analog switch and coupling the infrared modulation signal received by receiver 20 into HC4051_X. This signal is then transmitted to the input terminals of the first and second signal amplification circuits.

[0103] 5: The first signal amplification circuit 2032 and the second signal amplification circuit 2033 amplify and filter the received signal, and transmit the signal to the first receiving control module 201 and the second receiving control module 202 respectively. The first receiving control module 201 and the second receiving control module 202 process the signal, and then output the signal to the first output module 204 and the second output module 205 respectively. After passing through the Darlington transistor, the signal is output to the relay of the external device.

[0104] The above are merely embodiments of this utility model and do not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the description and drawings of this utility model, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A safety light curtain, comprising a transmitter for emitting infrared signals and a receiver for receiving the infrared signals, characterized in that, The receiver includes: First receiving control module; A second receiving control module is connected to the first receiving control module. A first output module, which is connected to the first receiving control module; The second output module is connected to the second receiving control module. The receiving signal processing module further includes: A signal receiving circuit, wherein the signal receiving circuit is connected to the first receiving control module; A first signal amplification circuit is connected to the signal receiving circuit and the first receiving control module, respectively. The second signal amplification circuit is connected to the signal receiving circuit and the second receiving control module, respectively. A receiving signal processing circuit is provided, which is connected to both the signal receiving circuit and the first receiving control module.

2. The safety light curtain according to claim 1, characterized in that, The receiver also includes: A first output detection module is connected to both the first output module and the first receiving control module. The second output detection module is connected to both the second output module and the second receiving control module.

3. The safety light curtain according to claim 1, characterized in that, The receiver further includes a first indication module, which is connected to the first receiving control module and includes a first light energy indication submodule, a first output status indication submodule, and a first fault indication submodule.

4. The safety light curtain according to claim 1, characterized in that, The receiver also includes: A first power supply module, which is connected to the first receiving control module; The second power supply module is connected to the second receiving control module.

5. The safety light curtain according to claim 1, characterized in that, The transmitter includes: Launch control module; A transmission signal processing module, which is connected to the transmission control module; The second indicator module, which is connected to the transmission control module, includes: a second optical energy indicator submodule, a second output status indicator submodule, and a second fault indicator submodule.

6. The safety light curtain according to claim 5, characterized in that, The receiver further includes a first communication module connected to the first receiving control module; the transmitter further includes a second communication module connected to the transmitting control module, wherein the first communication module and the second communication module establish a communication connection.

7. The safety light curtain according to claim 5, characterized in that, The transmitter also includes an auxiliary output module connected to the transmission control module.

8. The safety light curtain according to claim 5, characterized in that, The transmitter also includes an external device monitoring module connected to the transmission control module.

9. The safety light curtain according to claim 5, characterized in that, The transmitter also includes a third power supply module connected to the transmission control module.

10. The safety light curtain according to claim 5, characterized in that, The transmitted signal processing module further includes: A signal transmitting circuit, which is connected to the transmitting control module; A signal processing circuit is provided, which is connected to both the signal transmitting circuit and the transmission control module.

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