Alarm control circuit

Abstract

The invention belongs to the technical field of alarm control, and particularly discloses an alarm control circuit, which comprises a power supply circuit, an alarm acquisition circuit, a logic combination circuit and an enabling control circuit: the power supply circuit is used for converting externally input 28V direct current into 5V direct current to supply power to the alarm control circuit; the alarm acquisition circuit is used for acquiring switching value alarm signals of a plurality of devices; the logic combination circuit is connected with the alarm acquisition circuit, and is used for carrying out negation operation and AND operation on switching value alarm signals of a plurality of devices, synthesizing the switching value alarm signals into a signal and inputting the signal into the enabling control circuit; the enabling control circuit is connected with the logic combination circuit, and is used for normally enabling the controlled device when the switching value alarm signals of the multiple devices are invalid, and turning off enabling signals of the controlled device and enabling the controlled device to stop working when at least one path of the switching value alarm signals of the multiple devices is valid. And meanwhile, an alarm indicating lamp corresponding to the equipment with the effective switching value alarm signal is lightened.

Description

Technical Field

[0001] This application belongs to the field of alarm control technology, and more specifically, relates to an alarm control circuit. Background Technology

[0002] Alarm controllers are playing an increasingly important role in the safety management of equipment systems, and their applications are becoming more and more widespread. However, traditional alarm controllers are usually designed and implemented by combining electronic hardware and microcontroller unit (MCU) software. This involves both electronic hardware design and MCU software development, requiring a significant investment of manpower and resulting in high costs. Summary of the Invention

[0003] In view of the shortcomings of the prior art, the purpose of this application is to provide an alarm control circuit that aims to solve the problem of high cost caused by the combination of electronic hardware and MCU software in the design of existing alarm controllers.

[0004] To achieve the above objectives, in a first aspect, this application provides an alarm control circuit, comprising: a power supply circuit, an alarm acquisition circuit, a logic combination circuit, and an enable control circuit. The power supply circuit is used to convert the externally input 28V DC power into 5V DC power to power the alarm control circuit. The alarm acquisition circuit is used to acquire switch alarm signals from multiple devices. The logic combination circuit and the alarm acquisition circuit are connected to each other and are used to invert the switch alarm signals of the multiple devices and then perform an AND operation to synthesize a signal and input it into the enable control circuit. The enable control circuit and the logic combination circuit are connected to enable the controlled device normally when the switch alarm signals of multiple devices are invalid, and disable the enable signal of the controlled device and stop the controlled device from working when at least one switch alarm signal of multiple devices is valid, while illuminating the alarm indicator corresponding to the device with the valid switch alarm signal.

[0005] This application designs a purely electronic hardware-based alarm control circuit that does not contain an MCU device, eliminating the need for conventional MCU software design, saving product development time and software design personnel investment, simplifying the alarm control circuit, improving reliability, shortening the product's response time to alarm signals, and improving the circuit's safety management performance. It can simultaneously collect switch alarm signals from multiple devices and light up the corresponding alarm indicator lights, realizing alarms for various device faults or safety hazards. At the same time, when any device alarm signal is valid, it can automatically shut down the controlled device, realizing safe management and control of the controlled device, with complete functions.

[0006] According to an alarm control circuit provided in this application, the power supply circuit includes a first filter, a power module, a power switch, a power indicator light, a ferrite bead, a first filter capacitor, and a second filter capacitor, wherein: The power switch is used to control the on / off state of the externally input 28V DC power. The filter is connected to the power switch and is used to filter the externally input 28V DC power. The power module and the filter are connected to convert the input 28V DC power into 5V DC power. The power indicator light is connected to the power switch and is used to indicate the status of the power switch; The magnetic bead is connected to the output terminal of the power module and is used to absorb the ultra-high frequency signal of the 5V DC power output by the power module. The first filter capacitor and the second filter capacitor are respectively connected to the output terminal of the power module to filter the 5V DC power output by the power module.

[0007] According to an alarm control circuit provided in this application, the alarm acquisition circuit includes a first optocoupler, a second optocoupler, multiple current-limiting resistors, multiple filter capacitors, multiple switching diodes, multiple pull-up resistors, multiple alarm lights, and multiple alarm signal input terminals. The multiple alarm signal input terminals are used to receive switch alarm signals from multiple devices respectively; The multiple filter capacitors are used to reduce 28V power supply ripple noise; The plurality of current-limiting resistors are used to limit the current flowing into the light-emitting diodes inside the first optocoupler and the second optocoupler. The multiple switching diodes are connected in reverse parallel to prevent the light-emitting diodes in the optocoupler from being broken down by the reverse electromotive force. The plurality of pull-up resistors are used to pull up pin 16 of the optocoupler output terminal; The first optocoupler and the second optocoupler are used to electrically isolate the switch alarm signals of multiple devices, and also to collect the switch alarm signals of multiple devices; The multiple alarm lights are used to indicate that the multiple devices are malfunctioning.

[0008] According to an alarm control circuit provided in this application, the logic combination circuit includes a logic inverter circuit and a logic AND gate circuit: The logic inverting circuit is used to invert the switch alarm signals of the multiple devices. The logic AND gate circuit is used to perform AND operations on the switch alarm signals of multiple devices after inversion.

[0009] According to an alarm control circuit provided in this application, the logic inverting circuit includes an inverter and a third filter capacitor: The inverter is used to logically invert the input alarm signal; The filter capacitor is used to reduce 5V power supply ripple noise.

[0010] According to an alarm control circuit provided in this application, the logic AND gate circuit includes an AND gate device, a fourth filter capacitor, and a fifth filter capacitor: The fourth and fifth filter capacitors are used to reduce 5V power supply ripple noise. The AND gate device is used to perform an AND operation on all the switch alarm signals of multiple devices after the inversion operation.

[0011] According to an alarm control circuit provided in this application, the enable control circuit includes a third optocoupler, multiple current-limiting resistors, an enable switch, an enable indicator light, and an enable signal output terminal. The multiple current-limiting resistors are used to limit the current flowing into the light-emitting diode inside the third optocoupler; The enable switch is used to control the on / off state of the output enable signal; The enable indicator light is used to indicate whether the enable signal is output; The enable signal output terminal is used to output an enable signal to the controlled device; The third optocoupler is used to electrically isolate the fused alarm signal from the enable signal, and also to transmit the enable signal to the enable signal output terminal.

[0012] Overall, the technical solutions conceived in this application have the following beneficial effects compared with the prior art: This application designs a purely electronic hardware-based alarm control circuit that does not contain an MCU device, eliminating the need for conventional MCU software design, saving product development time and software design personnel investment, simplifying the alarm control circuit, improving reliability, shortening the product's response time to alarm signals, and improving the circuit's safety management performance. It can simultaneously collect switch alarm signals from multiple devices and light up the corresponding alarm indicator lights, realizing alarms for various device faults or safety hazards. At the same time, when any device alarm signal is valid, it can automatically shut down the controlled device, realizing safe management and control of the controlled device, with complete functions. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is one of the structural schematic diagrams of the alarm control circuit provided in the embodiments of this application; Figure 2 This is a second schematic diagram of the alarm control circuit provided in the embodiments of this application; Figure 3 This is a circuit diagram of the power supply circuit provided in an embodiment of this application; Figure 4 This is a circuit diagram of the alarm acquisition circuit provided in the embodiments of this application; Figure 5 This is a circuit diagram of the logic inverting circuit provided in the embodiments of this application; Figure 6 This is a circuit diagram of the logic AND gate circuit provided in the embodiments of this application; Figure 7 This is a circuit diagram of the enable control circuit provided in the embodiments of this application. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0016] In this article, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. The symbol " / " in this article indicates that the related objects are in an "or" relationship; for example, A / B means A or B.

[0017] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0018] In the description of the embodiments of this application, unless otherwise stated, "multiple" means two or more, for example, multiple processing units means two or more processing units, multiple elements means two or more elements, etc.

[0019] Next, combined Figures 1-7 The alarm control circuit provided in the embodiments of this application will be described.

[0020] Figure 1 This is one of the structural schematic diagrams of the alarm control circuit provided in the embodiments of this application, such as... Figure 1 As shown, the circuit 100 includes a power supply circuit, an alarm acquisition circuit, a logic combination circuit, and an enable control circuit: The power supply circuit 110 is used to convert the externally input 28V DC power into 5V DC power to power the alarm control circuit; Alarm acquisition circuit 120 is used to acquire switch alarm signals from multiple devices; The logic combination circuit 130 and the alarm acquisition circuit 120 are connected to each other to invert and then AND the switch alarm signals of multiple devices, synthesize them into one signal and input it into the enable control circuit 140. The enable control circuit 140 and the logic combination circuit 130 are connected to enable the controlled device normally when the switch alarm signals of multiple devices are invalid, and turn off the enable signal of the controlled device and stop the controlled device from working when at least one switch alarm signal of multiple devices is valid, while illuminating the alarm indicator corresponding to the device with the valid switch alarm signal.

[0021] Figure 2 This is a second schematic diagram of the alarm control circuit provided in the embodiments of this application, as shown below. Figure 2 As shown in one embodiment of this application, taking six devices as an example, the alarm control circuit includes a power supply circuit, an alarm acquisition circuit, a logic combination circuit, an enable control circuit, a power switch, a power indicator light, an enable switch, an enable indicator light, six alarm indicator lights, six alarm signal input interfaces, and one enable signal output interface. The alarm control circuit is powered by 28V DC, which is converted to 5V DC by a filter and a power module to power the logic devices. After the alarm acquisition circuit acquires the switch alarm signals input by devices A to F, the logic combination circuit first inverts the switch alarm signals and then performs an AND operation to synthesize a single signal for input to the subsequent enable control circuit. This ensures that when all six alarm signals are invalid, device G is enabled normally. When any one of the six alarm signals is valid, the enable signal of device G is turned off, device G stops working, and the corresponding alarm indicator light illuminates, thus achieving safety control.

[0022] The alarm control circuit provided in this application is a purely electronic hardware implementation, without MCU devices, eliminating the need for conventional MCU software design, saving product development time and software design personnel investment, simplifying the alarm control circuit, improving reliability, shortening the product's response time to alarm signals, and improving circuit safety management performance. It can simultaneously collect switch alarm signals from multiple devices and light up the corresponding alarm indicator lights, realizing alarms for various device faults or safety hazards. At the same time, when any device alarm signal is valid, it can automatically shut down the controlled device, realizing safety management of the controlled device, with complete functions.

[0023] In some embodiments, the power supply circuit 110 includes a first filter, a power module, a power switch, a power indicator light, a ferrite bead, a first filter capacitor, and a second filter capacitor, wherein: The power switch is used to control the on / off state of the externally input 28V DC power. The filter is connected to the power switch and is used to filter the externally input 28V DC power. The power module and filter are connected to convert the input 28V DC power into 5V DC power; The power indicator light is connected to the power switch and is used to indicate the status of the power switch; The ferrite bead is connected to the output terminal of the power module to absorb the ultra-high frequency signal of the 5V DC power output by the power module. The first and second filter capacitors are connected to the output terminals of the power module to filter the 5V DC power output by the power module.

[0024] Figure 3 This is a circuit diagram of the power supply circuit provided in an embodiment of this application, as shown below. Figure 3As shown, in one embodiment of this application, the power supply circuit includes a filter N1, a power module N2, a power switch KEY1, a power indicator LED1, a ferrite bead L1, and filter capacitors C7 and C8. The positive terminal (DC28V+) of the externally input 28V DC power is connected to pin 1 of the power switch KEY1, and the negative terminal (DC28V-) of the 28V DC power is connected to pin 2 of the power indicator LED1 and pin 2 of the filter N1. Pin 2 of the power switch KEY1 is connected to pin 1 of the power indicator LED1 and pin 1 of the filter N1. N1's model number is CXDD5-3-50, with a rated current of 3A. Its pin 4 is connected to pin 1 of power module N2, and its pin 3 is connected to pin 2 of power module N2. Power module N2's model number is RP15-2405SF, with a power rating of 15W. Its pin 3 is connected to pin 1 of ferrite bead L1, filter capacitors C7 and C8, and its pin 5 is connected to pin 2 of filter capacitors C7 and C8. The capacitance of filter capacitor C7 is 0.1µF, the capacitance of filter capacitor C8 is 10µF, and the model number of ferrite bead L1 is PB1608-121 / 3A.

[0025] Filter N1 suppresses electromagnetic interference and prevents high-frequency noise from entering the circuit and affecting its operation. Power module N2 converts the input 28V DC power into 5V DC power for use by subsequent circuits. Power switch KEY1 controls the input of 28V DC power to the alarm control circuit. Power indicator LED1 indicates whether 28V DC power is being supplied to the alarm control circuit; an illuminated LED indicates that the alarm control circuit is powered, while an off LED indicates that the alarm control circuit is not powered. The ferrite bead L1, filter capacitors C7 and C8 at the output of power module N2 reduce the output ripple noise of power module N2, suppress high-frequency interference, and stabilize voltage quality.

[0026] In some embodiments, the alarm acquisition circuit 120 includes a first optocoupler, a second optocoupler, multiple current-limiting resistors, multiple filter capacitors, multiple switching diodes, multiple pull-up resistors, multiple alarm lights, and multiple alarm signal input terminals. Multiple alarm signal input terminals are used to receive switch alarm signals from multiple devices respectively; Multiple filter capacitors are used to reduce 28V power supply ripple noise; Multiple current-limiting resistors are used to limit the current flowing into the light-emitting diodes inside the first and second optocouplers; Multiple switching diodes are connected in reverse parallel to prevent the light-emitting diodes in the optocoupler from being broken down by the reverse electromotive force; Multiple pull-up resistors are used to pull up the 16 pins of the optocoupler output. The first and second optocouplers are used to electrically isolate the switch alarm signals of multiple devices, and also to collect the switch alarm signals of multiple devices. Multiple alarm lights are used to indicate that multiple devices are malfunctioning.

[0027] Figure 4 This is a circuit diagram of the alarm acquisition circuit provided in the embodiments of this application, as shown below. Figure 4As shown, in one embodiment of this application, the alarm acquisition circuit includes optocouplers U1 and U2, current-limiting resistors R1-R6, filter capacitors C1-C6, switching diodes V1-V6, pull-up resistors R7-R12, alarm lights BULB_A-BULB_F, and alarm signal input terminals PIN_A-PIN_F. Pin 2 of the alarm signal input terminal PIN_A is connected to 28V_GND, and pin 1 of PIN_A is connected to pin 2 of the filter capacitor C1 and the switching diode. Pin 1 of transistor V1 and pin 2 of optocoupler U1; +28V is connected to pin 1 of current-limiting resistor R1 and pin 1 of filter capacitor C1; pin 2 of current-limiting resistor R1 is connected to pin 2 of switching diode V1 and pin 1 of optocoupler U1; pin 15 of optocoupler U1 is connected to 5V_GND and pin 2 of alarm lamp BULB_A; pin 16 of optocoupler U1 is connected to A_AR, pin 2 of pull-up resistor R7 and pin 1 of alarm lamp BULB_A; pin 1 of pull-up resistor R7 is connected to +5V. Pin 2 of the alarm signal input terminal PIN_B is connected to 28V_GND. Pin 1 of PIN_B is connected to pin 2 of filter capacitor C2, pin 1 of switching diode V2, and pin 4 of optocoupler U1. +28V is connected to pin 1 of current-limiting resistor R2 and pin 1 of filter capacitor C2. Pin 2 of current-limiting resistor R2 is connected to pin 2 of switching diode V2 and pin 3 of optocoupler U1. Pin 13 of optocoupler U1 is connected to 5V_GND and pin 2 of alarm lamp BULB_B. Pin 14 of optocoupler U1 is connected to B_AR, pin 2 of pull-up resistor R8, and pin 1 of alarm lamp BULB_B. Pin 1 of pull-up resistor R8 is connected to +5V. Pin 2 of the alarm signal input terminal PIN_C is connected to 28V_GND. Pin 1 of PIN_C is connected to pin 2 of filter capacitor C3, pin 1 of switching diode V3, and pin 6 of optocoupler U1. +28V is connected to pin 1 of current-limiting resistor R3 and pin 1 of filter capacitor C3. Pin 2 of current-limiting resistor R3 is connected to pin 2 of switching diode V3 and pin 5 of optocoupler U1. Pin 11 of optocoupler U1 is connected to 5V_GND and pin 2 of alarm lamp BULB_C. Pin 12 of optocoupler U1 is connected to C_AR, pin 2 of pull-up resistor R9, and pin 1 of alarm lamp BULB_C. Pin 1 of pull-up resistor R9 is connected to +5V. Pin 2 of the alarm signal input terminal PIN_D is connected to 28V_GND. Pin 1 of PIN_D is connected to pin 2 of the filter capacitor C4, pin 1 of the switching diode V4, and pin 8 of the optocoupler U1. +28V is connected to pin 1 of the current-limiting resistor R4 and pin 1 of the filter capacitor C4. Pin 2 of the current-limiting resistor R4 is connected to pin 2 of the switching diode V4 and pin 7 of the optocoupler U1. Pin 9 of the optocoupler U1 is connected to 5V_GND and pin 2 of the alarm lamp BULB_D. Pin 10 of the optocoupler U1 is connected to D_AR, pin 2 of the pull-up resistor R10, and pin 1 of the alarm lamp BULB_D. Pin 1 of the pull-up resistor R10 is connected to +5V.Pin 2 of the alarm signal input terminal PIN_E is connected to 28V_GND. Pin 1 of PIN_E is connected to pin 2 of filter capacitor C5, pin 1 of switching diode V5, and pin 2 of optocoupler U2. +28V is connected to pin 1 of current-limiting resistor R5 and pin 1 of filter capacitor C5. Pin 2 of current-limiting resistor R5 is connected to pin 2 of switching diode V5 and pin 1 of optocoupler U2. Pin 15 of optocoupler U2 is connected to 5V_GND and pin 2 of alarm lamp BULB_E. Pin 16 of optocoupler U2 is connected to E_AR, pin 2 of pull-up resistor R11, and pin 1 of alarm lamp BULB_E. Pin 1 of pull-up resistor R11 is connected to +5V. Pin 2 of the alarm signal input terminal PIN_F is connected to 28V_GND. Pin 1 of PIN_F is connected to pin 2 of the filter capacitor C6, pin 1 of the switching diode V6, and pin 4 of the optocoupler U2. +28V is connected to pin 1 of the current-limiting resistor R6 and pin 1 of the filter capacitor C6. Pin 2 of the current-limiting resistor R6 is connected to pin 2 of the switching diode V6 and pin 3 of the optocoupler U2. Pin 13 of the optocoupler U2 is connected to 5V_GND and pin 2 of the alarm lamp BULB_F. Pin 14 of the optocoupler U2 is connected to F_AR, pin 2 of the pull-up resistor R12, and pin 1 of the alarm lamp BULB_F. Pin 1 of the pull-up resistor R12 is connected to +5V.

[0028] The alarm signal input terminals PIN_A~PIN_F are the alarm signal input interfaces for devices A to F, and the alarm signals are switch signals. The filter capacitors C1~C6 have a capacitance of 0.1µF and are used to reduce 28V power supply ripple noise. The current-limiting resistors R1~R6 have a resistance of 2.4KΩ and are used to limit the current flowing into the LEDs inside optocouplers U1 and U2 to prevent excessive current from burning out the optocouplers. The reverse-parallel switching diodes V1~V6 are in a reverse-biased state during normal operation, which has no effect on the circuit compared to an open circuit. When turned off, they generate a reverse electromotive force, causing the diodes to be forward-biased. When the diode is turned on, it provides a low-impedance discharge path for the reverse current, thereby clamping the reverse voltage applied across the LED of the optocoupler to the forward voltage drop of the diode, preventing the LED in the optocoupler from being broken down by the reverse electromotive force; the pull-up resistors R7~R12 have a resistance of 200Ω, which pull up pin 16 of the output terminal of optocoupler U1 and U2; optocouplers U1 and U2 have 4 independent channels (A, B, C, D), model HRG3105J-4; the alarm lights BULB_A~BULB_F correspond to the indication of abnormal operation of devices A to F respectively. The working principle is as follows: When there is no alarm, pins 1 and 2 of the alarm signal input terminals PIN_A~PIN_F are connected, the LEDs on the input side of optocouplers U1 and U2 light up, and the phototransistors on the output side change from the cutoff state to the on state after receiving light, and the output signals A_AR~F_AR are low level; the alarm lights BULB_A~BULB_F are not lit. When there is an alarm, pins 1 and 2 of the alarm signal input terminals PIN_A~PIN_F are disconnected, the LEDs on the input side of optocouplers U1 and U2 do not light up, the phototransistors on the output side do not receive light, change from the on state to the cutoff state, the output signals A_AR~F_AR are high level, and the alarm lights BULB_A~BULB_F are lit.

[0029] In some embodiments, the logic combination circuit 130 includes a logic inverter circuit and a logic AND gate circuit: The logic inverting circuit is used to invert the switch alarm signals of multiple devices. AND gates are used to perform AND operations on the switch alarm signals of multiple devices after inversion.

[0030] In some embodiments, the logic inverting circuit includes an inverter and a third filter capacitor: An inverter is used to logically invert the input alarm signal; The filter capacitor is used to reduce 5V power supply ripple noise.

[0031] Figure 5 This is a circuit diagram of the logic inverting circuit provided in the embodiments of this application, such as... Figure 5As shown, in one embodiment of this application, the logic inverting circuit includes an inverter N3 and a filter capacitor C9. +5V is connected to pin 1 of the filter capacitor C9 and pin 14 of the inverter N3; 5V_GND is connected to pin 2 of the filter capacitor C9 and pin 7 of the inverter N3; A_AR is connected to pin 1 of the inverter N3; A_WARN is connected to pin 2 of the inverter N3; B_AR is connected to pin 3 of the inverter N3; B_WARN is connected to pin 4 of the inverter N3; C_AR is connected to pin 5 of the inverter N3; C_WARN is connected to pin 6 of the inverter N3; D_AR is connected to pin 9 of the inverter N3; D_WARN is connected to pin 8 of the inverter N3; E_AR is connected to pin 11 of the inverter N3; E_WARN is connected to pin 7 of the inverter N3. Pin 10 of inverter N3 is connected to pin 13 of inverter N3, and pin 12 of inverter N3 is connected to pin 13 of inverter N3. Inverter N3 is powered by 5V DC, and the capacitance of filter capacitor C9 is 0.47µF to reduce 5V power supply ripple noise. Inverter N3 is model SN74HC04N, which realizes the logic inversion of its 6 input alarm signals A_AR~F_AR, and outputs alarm signals A_WARN~F_WARN. When there is no alarm, A_AR~F_AR is low level, and A_WARN~F_WARN is high level (5V). When there is an alarm, A_AR~F_AR is high level, and A_WARN~F_WARN is low level (0V).

[0032] In some embodiments, the logic AND gate circuit includes an AND gate device, a fourth filter capacitor, and a fifth filter capacitor: The fourth and fifth filter capacitors are used to reduce 5V power supply ripple noise; AND gate devices are used to perform an AND operation on all the switch alarm signals of multiple devices after inversion.

[0033] Figure 6 This is a circuit diagram of the logic AND gate circuit provided in the embodiments of this application, such as... Figure 6As shown, in one embodiment of this application, the logic AND gate circuit includes AND gate devices N4~N5 and filter capacitors C10~C11. +5V is connected to pin 1 of filter capacitors C10~C111 and pin 14 of AND gate devices N4~N5. 5V_GND is connected to pin 2 of filter capacitors C10~C11 and pin 7 of AND gate devices N4~N5. A_WARN is connected to pin 1 of AND gate device N4, B_WARN is connected to pin 2 of AND gate device N4, C_WARN is connected to pin 4 of AND gate device N4, D_WARN is connected to pin 5 of AND gate device N4, and E_WARN is connected to pin 5 of AND gate device N4. RN is connected to pin 9 of AND gate N4, F_WARN is connected to pin 10 of AND gate N4, AB_WARN is connected to pins 12 and 3 of AND gate N4, CD_WARN is connected to pins 13 and 6 of AND gate N4, EF_WARN is connected to pin 8 of AND gate N4 and pins 2, 5, 10 and 13 of AND gate N5, ABCD_WARN is connected to pin 11 of AND gate N4 and pins 1, 4, 9 and 12 of AND gate N5, and ABCDEF_WARN is connected to pins 3, 6, 8 and 11 of AND gate N5. AND gates N4-N5 are powered by 5V DC. The filter capacitors C10-C11 have a capacitance of 0.47µF to reduce the 5V power supply ripple noise. The AND gates N4-N5 are of model SN74HC08N. They perform an AND operation on all six alarm signals A_WARN-F_WARN. The combined alarm signal ABCDEF_WARN is high (5V) only when all A_WARN-F_WARN are high (5V), i.e., when no alarm signal is valid. The combined alarm signal ABCDEF_WARN is low (0V) as long as any one of A_WARN-F_WARN is low (0V).

[0034] In some embodiments, the enable control circuit includes a third optocoupler, multiple current-limiting resistors, an enable switch, an enable indicator light, and an enable signal output terminal. Multiple current-limiting resistors are used to limit the current flowing into the light-emitting diode inside the third optocoupler; The enable switch is used to control whether the output enable signal is on or off; The enable indicator light is used to indicate whether the enable signal is output; The enable signal output terminal is used to output an enable signal to the controlled device; The third optocoupler is used to electrically isolate the fused alarm signal from the enable signal, and also to transmit the enable signal to the enable signal output terminal.

[0035] Figure 7 This is a circuit diagram of the enable control circuit provided in the embodiments of this application, such as... Figure 7As shown, in one embodiment of this application, +5V is connected to pin 1 of the current-limiting resistor R13, pin 2 of the current-limiting resistor R13 is connected to pin 1 of the optocoupler U3, ABCDEF_WARN is connected to pin 2 of the optocoupler U3, pins 15 and 6 of the optocoupler U3 are connected to 28V_GND, pin 16 of the optocoupler U3 is connected to pin 2 of the current-limiting resistor R14 and pin 3 of the optocoupler U3, pin 1 of the current-limiting resistor R14 is connected to pin 2 of the enable switch KEY2, pin 1 of the enable switch KEY2 is connected to +28V, pin 4 of the optocoupler U3 is connected to pin 5, pin 14 of the optocoupler U3 is connected to pin 1 of the enable signal output terminal PIN_G, pin 13 of the optocoupler U3 is connected to pin 2 of the enable signal output terminal PIN_G, pin 12 of the optocoupler U3 is connected to +28V, pin 1 of the enable indicator LED2 is connected to pin 11 of the optocoupler U3, and pin 2 of the enable indicator LED2 is connected to 28V_GND.

[0036] The current-limiting resistor R13 has a resistance of 470Ω, and the current-limiting resistor R14 has a resistance of 3KΩ. These resistors are used to limit the current flowing into the LED inside the optocoupler U3 to prevent excessive current from burning out the optocoupler. The optocoupler U3 has four independent channels (A, B, C, D) and is model HRG3105J-4. The enable switch KEY2 enables the output enable signal. The enable indicator LED2 indicates whether the enable signal is output. The enable signal output terminal PIN_G serves as the enable signal output interface and is connected to device G. The working principle is as follows: When enable switch KEY2 is closed, if no alarm signal is active, the synthesized alarm signal ABCDEF_WARN is high (5V). The LED on the A-side of optocoupler U3 does not emit light, and the output phototransistor is not illuminated and is in a cutoff state. Current flows into the LEDs on the B and C-sides of optocoupler U3, causing them to emit light. Upon receiving light, the output phototransistors on the B and C-sides change from a cutoff state to a conducting state, outputting an enable signal EN to device G. Simultaneously, the enable indicator LED2 lights up. When any alarm signal is active, the signal will activate. When the alarm signal is valid, the synthesized alarm signal ABCDEF_WARN is low (0V). The LED on the input side of the optocoupler U3 illuminates, and the phototransistor on the output side receives the light and changes from the cutoff state to the conduction state. Current flows to the phototransistor on the output side of the optocoupler U3. The LEDs on the input sides of the optocoupler U3 (B and C) do not illuminate. After the phototransistors on the output sides of the optocoupler U3 (B and C) do not receive the light, they change from the conduction state to the cutoff state, turning off the output enable signal EN to the G device. At the same time, the enable indicator LED2 turns off, realizing the safety control of the G device.

[0037] It is understood that the various numerical designations used in the embodiments of this application are merely for the convenience of description and are not intended to limit the scope of the embodiments of this application.

[0038] Those skilled in the art will readily understand that the above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. An alarm control circuit, characterized in that, Includes power supply circuit, alarm acquisition circuit, logic combination circuit, and enable control circuit: The power supply circuit is used to convert the externally input 28V DC power into 5V DC power to power the alarm control circuit. The alarm acquisition circuit is used to acquire switch alarm signals from multiple devices. The logic combination circuit and the alarm acquisition circuit are connected to each other and are used to invert the switch alarm signals of the multiple devices and then perform an AND operation to synthesize a signal and input it into the enable control circuit. The enable control circuit and the logic combination circuit are connected to enable the controlled device normally when the switch alarm signals of multiple devices are invalid, and disable the enable signal of the controlled device and stop the controlled device from working when at least one switch alarm signal of multiple devices is valid, while illuminating the alarm indicator corresponding to the device with the valid switch alarm signal.

2. The alarm control circuit according to claim 1, characterized in that, The power supply circuit includes a first filter, a power module, a power switch, a power indicator light, a ferrite bead, a first filter capacitor, and a second filter capacitor, wherein: The power switch is used to control the on / off state of the externally input 28V DC power. The filter is connected to the power switch and is used to filter the externally input 28V DC power. The power module and the filter are connected to convert the input 28V DC power into 5V DC power. The power indicator light is connected to the power switch and is used to indicate the status of the power switch; The magnetic bead is connected to the output terminal of the power module and is used to absorb the ultra-high frequency signal of the 5V DC power output by the power module. The first filter capacitor and the second filter capacitor are respectively connected to the output terminal of the power module to filter the 5V DC power output by the power module.

3. The alarm control circuit according to claim 1, characterized in that, The alarm acquisition circuit includes a first optocoupler, a second optocoupler, multiple current-limiting resistors, multiple filter capacitors, multiple switching diodes, multiple pull-up resistors, multiple alarm lights, and multiple alarm signal input terminals. The multiple alarm signal input terminals are used to receive switch alarm signals from multiple devices respectively; The multiple filter capacitors are used to reduce 28V power supply ripple noise; The plurality of current-limiting resistors are used to limit the current flowing into the light-emitting diodes inside the first optocoupler and the second optocoupler. The multiple switching diodes are connected in reverse parallel to prevent the light-emitting diodes in the optocoupler from being broken down by the reverse electromotive force. The plurality of pull-up resistors are used to pull up pin 16 of the optocoupler output terminal; The first optocoupler and the second optocoupler are used to electrically isolate the switch alarm signals of multiple devices, and also to collect the switch alarm signals of multiple devices; The multiple alarm lights are used to indicate that the multiple devices are malfunctioning.

4. The alarm control circuit according to claim 1, characterized in that, The logic combinational circuit includes a logic inverter circuit and a logic AND gate circuit: The logic inverting circuit is used to invert the switch alarm signals of the multiple devices. The logic AND gate circuit is used to perform AND operations on the switch alarm signals of multiple devices after inversion.

5. The alarm control circuit according to claim 4, characterized in that, The logic inverting circuit includes an inverter and a third filter capacitor: The inverter is used to logically invert the input alarm signal; The filter capacitor is used to reduce 5V power supply ripple noise.

6. The alarm control circuit according to claim 4, characterized in that, The logic AND gate circuit includes an AND gate device, a fourth filter capacitor, and a fifth filter capacitor: The fourth and fifth filter capacitors are used to reduce 5V power supply ripple noise. The AND gate device is used to perform an AND operation on all the switch alarm signals of multiple devices after the inversion operation.

7. The alarm control circuit according to claim 1, characterized in that, The enable control circuit includes a third optocoupler, multiple current-limiting resistors, an enable switch, an enable indicator light, and an enable signal output terminal. The multiple current-limiting resistors are used to limit the current flowing into the light-emitting diode inside the third optocoupler; The enable switch is used to control the on / off state of the output enable signal; The enable indicator light is used to indicate whether the enable signal is output; The enable signal output terminal is used to output an enable signal to the controlled device; The third optocoupler is used to electrically isolate the fused alarm signal from the enable signal, and also to transmit the enable signal to the enable signal output terminal.

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