Equipment overload protection circuit for industrial internet

Abstract

The utility model relates to the technical field of protection circuits, in particular to an equipment overload protection circuit for industrial internet, which comprises an amplifying circuit, a comparison circuit, a prompt circuit and a judgment circuit, the amplifying circuit is used for sampling, converting and amplifying current signals, the comparison circuit is used for judging whether abnormal voltage occurs or not, and the prompt circuit is used for prompting whether the abnormal voltage occurs or not. The judgment circuit is used for judging whether an overload condition occurs or not. According to the utility model, the amplifying circuit is used for amplifying a voltage signal, then the comparison circuit is used for judging whether the normal working voltage is exceeded, when the equipment is overloaded, the output end of the voltage comparator U2 outputs high level, the indicating lamp L is lightened, and the judgment circuit drives the relay KA to disconnect the equipment circuit only when the overload time exceeds a certain duration; and the circuit is not switched off when the equipment is temporarily overloaded in a bearable range, so that the practicability is higher.

Description

Technical Field

[0001] The utility model relates to the technical field of protection circuits, and specifically, to an overload protection circuit for industrial Internet equipment. Background Art

[0002] The safety of industrial equipment is an important indicator of quality. In actual use, the equipment may sometimes be overloaded due to various reasons. It is necessary to have corresponding protection circuits to cut off the circuit in time when the equipment is overloaded to protect the safety of the equipment.

[0003] The utility model patent with application number CN201921733338.2 discloses an overload protection circuit and electronic device, including: a switching circuit, a sampling circuit, a signal amplifying circuit, an equalizing circuit, a self-locking circuit and a microcontroller unit; the input port of the switching circuit is connected to the control port of the microcontroller unit through the equalizing circuit, and the output port of the switching circuit is connected to the load driving circuit; the input port of the sampling circuit is connected to the load driving circuit, and the output port of the sampling circuit is connected to the signal amplifying circuit; the input port of the signal amplifying circuit is connected to the output port of the sampling circuit, and the output port of the signal amplifying circuit is connected to the self-locking circuit; the input port of the self-locking circuit is connected to the signal amplifying circuit, and the output port of the self-locking circuit is connected to the input port of the switching circuit.

[0004] Although the utility model realizes overload protection for the load driving circuit, when the device is actually used, a brief current surge may occur due to various reasons such as unstable power supply, operating environment, and connection and disconnection of other devices. However, this situation will not affect the operation of the device, and the designer has designed the corresponding circuit to deal with it. At this time, there is no need to disconnect the device. Disconnecting the device will affect production, which is not very practical. Utility Model Content

[0005] The purpose of the utility model is to provide an overload protection circuit for industrial Internet equipment to solve the problem proposed in the above background technology that a short-term current surge when the equipment is in use may cause the equipment to disconnect.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] An overload protection circuit for industrial Internet equipment includes an amplifier circuit, a comparison circuit, a prompt circuit and a judgment circuit. The amplifier circuit is used to sample, convert and amplify current signals, the comparison circuit is used to judge whether abnormal voltage occurs, and the judgment circuit is used to judge whether an overload occurs.

[0008] Preferably, the amplifying circuit comprises a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5 and an operational amplifier U1;

[0009] The first resistor R1 is connected in series in the device circuit, the first end of the second resistor R2 is connected to the first end of the first resistor R1, the second end of the second resistor R2 is connected to the inverting input terminal of the operational amplifier U1, the first end of the third resistor R3 is connected to the second end of the first resistor R1, the second end of the third resistor R3 is connected to the non-inverting input terminal of the operational amplifier U1, the first end of the fourth resistor R4 is grounded, the second end of the fourth resistor R4 is connected to the inverting input terminal of the operational amplifier U1, the first end of the fifth resistor R5 is connected to the non-inverting input terminal of the operational amplifier U1, and the second end of the fifth resistor R5 is connected to the output terminal of the operational amplifier U1.

[0010] Preferably, the comparison circuit comprises a voltage comparator U2 and a reference branch;

[0011] The reference branch includes a reference power supply E, a sixth resistor R6 and a seventh resistor R7, a first end of the sixth resistor R6 is connected to the positive electrode of the reference power supply E, a second end of the sixth resistor R6 is connected to the first end of the seventh resistor R7, and a first end of the seventh resistor R7 is connected to the inverting input end of the voltage comparator U2;

[0012] The output terminal of the operational amplifier U1 is connected to the non-inverting input terminal of the voltage comparator U2.

[0013] Preferably, the prompt circuit includes an eighth resistor R8 and an indicator light L;

[0014] A first end of the eighth resistor R8 is connected to the output end of the voltage comparator U2, a first end of the indicator light L is connected to the second end of the eighth resistor R8, and a second end of the indicator light L is grounded.

[0015] Preferably, the judgment circuit includes a 555 timer, a ninth resistor R9, a tenth resistor R10, a switch S, a first capacitor C1, a second capacitor C2, a relay KA and a buzzer BL;

[0016] A first end of the ninth resistor R9 is connected to the output end of the voltage comparator U2, a second end of the ninth resistor R9 is connected to the third pin of the 555 timer, a first end of the tenth resistor R10 is connected to the output end of the voltage comparator U2, a second end of the tenth resistor R10, the sixth pin of the 555 timer and the seventh pin of the 555 timer are all connected to the first end of the second capacitor C2, a second end of the second capacitor C2 is grounded, a first end of the first capacitor C1 is grounded, a second end of the first capacitor C1 is connected to the fifth pin of the 555 timer, a fourth pin of the 555 timer and the eighth pin of the 555 timer are all connected to the output end of the voltage comparator U2, a first pin of the 555 timer is grounded, a second pin of the 555 timer is connected to the first end of the switch S, a second end of the switch S is grounded, a third pin of the 555 timer is connected to the first end of the relay KA, a second end of the relay KA is connected to the first end of the buzzer BL, a second end of the buzzer BL is grounded, and the relay KA is used to control the circuit disconnection of the device.

[0017] Compared with the prior art, the beneficial effects of the utility model are:

[0018] The utility model converts the working current of the equipment into voltage by setting the first resistor R1 as the sampling resistor, which is then amplified by the operational amplifier U1, and then compared by the voltage comparator U2 to see whether it exceeds the normal working voltage. When the equipment is overloaded, the output end of the voltage comparator U2 outputs a high level, and the indicator light L lights up. The judgment circuit will drive the relay KA to disconnect the equipment circuit only when the overload time exceeds the preset time, so that the equipment will not disconnect the circuit when it is briefly overloaded within the tolerable range, and the utility model is more practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The overall circuit diagram of the utility model;

[0020] Figure 2 A circuit diagram of an amplifier circuit in a utility model;

[0021] Figure 3 A circuit diagram of a comparison circuit in the utility model;

[0022] Figure 4 A circuit diagram indicating a circuit in a utility model;

[0023] Figure 5 It is a circuit diagram of the judgment circuit in the utility model.

[0024] In the figure:

[0025] 1. Amplifier circuit;

[0026] 2. Comparison circuit;

[0027] 3. Prompt circuit;

[0028] 4. Judge the circuit. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the utility model to clearly and completely describe the technical solution in the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0030] See also Figure 1-Figure 5 , the utility model provides a technical solution:

[0031] The overload protection circuit for industrial Internet equipment includes an amplifier circuit 1, a comparison circuit 2, a prompt circuit 3 and a judgment circuit 4. The amplifier circuit 1 is used to sample, convert and amplify the current signal, the comparison circuit 2 is used to judge whether an abnormal voltage occurs, and the judgment circuit 4 is used to judge whether an overload occurs. When the equipment is briefly overloaded within the tolerable range, the circuit will not be disconnected, and the practicality is stronger.

[0032] In this embodiment, the amplifier circuit 1 includes a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5 and an operational amplifier U1;

[0033] The first resistor R1 is connected in series in the device circuit, the first end of the second resistor R2 is connected to the first end of the first resistor R1, the second end of the second resistor R2 is connected to the inverting input end of the operational amplifier U1, the first end of the third resistor R3 is connected to the second end of the first resistor R1, the second end of the third resistor R3 is connected to the non-inverting input end of the operational amplifier U1, the first end of the fourth resistor R4 is grounded, the second end of the fourth resistor R4 is connected to the inverting input end of the operational amplifier U1, the first end of the fifth resistor R5 is connected to the non-inverting input end of the operational amplifier U1, the second end of the fifth resistor R5 is connected to the output end of the operational amplifier U1, and the first resistor R1 is used as a sampling resistor to convert the current signal of the device into a voltage signal, which is then amplified by the operational amplifier U1.

[0034] Specifically, the comparison circuit 2 includes a voltage comparator U2 and a reference branch;

[0035] The reference branch includes a reference power supply E, a sixth resistor R6 and a seventh resistor R7, a first end of the sixth resistor R6 is connected to the positive electrode of the reference power supply E, a second end of the sixth resistor R6 is connected to the first end of the seventh resistor R7, and a first end of the seventh resistor R7 is connected to the inverting input end of the voltage comparator U2;

[0036] The output terminal of the operational amplifier U1 is connected to the non-inverting input terminal of the voltage comparator U2. The voltage comparator U2 is used to compare the voltage signal with the reference voltage signal. When the voltage signal is greater than the reference voltage signal, the output terminal of the voltage comparator U2 outputs a high level, otherwise it outputs a low level.

[0037] Further, the prompt circuit 3 includes an eighth resistor R8 and an indicator light L;

[0038] A first end of the eighth resistor R8 is connected to the output end of the voltage comparator U2, a first end of the indicator light L is connected to the second end of the eighth resistor R8, a second end of the indicator light L is grounded, and the indicator light L is used to indicate whether an abnormal current occurs.

[0039] It is worth noting that the judgment circuit 4 includes a 555 timer, a ninth resistor R9, a tenth resistor R10, a switch S, a first capacitor C1, a second capacitor C2, a relay KA and a buzzer BL;

[0040] A first end of the ninth resistor R9 is connected to the output end of the voltage comparator U2, a second end of the ninth resistor R9 is connected to the third pin of the 555 timer, a first end of the tenth resistor R10 is connected to the output end of the voltage comparator U2, a second end of the tenth resistor R10, the sixth pin of the 555 timer and the seventh pin of the 555 timer are all connected to the first end of the second capacitor C2, a second end of the second capacitor C2 is grounded, a first end of the first capacitor C1 is grounded, a second end of the first capacitor C1 is connected to the fifth pin of the 555 timer, a fourth pin of the 555 timer and the eighth pin of the 555 timer are all connected to the output end of the voltage comparator U2, a first pin of the 555 timer is grounded, a second pin of the 555 timer is connected to the first end of the switch S, a second end of the switch S is grounded, a third pin of the 555 timer is connected to the first end of the relay KA, a second end of the relay KA is connected to the first end of the buzzer BL, a second end of the buzzer BL is grounded, relay KA is used to control the circuit disconnection of the device, and relay KA will work only when the abnormal current time exceeds the preset time, and the preset time can be changed by replacing the tenth resistor R10 and the second capacitor C2.

[0041] When the industrial Internet equipment overload protection circuit of the utility model is in use, the first resistor R1 is connected in series in the equipment circuit. The first resistor R1 serves as a sampling resistor to convert the working voltage of the equipment circuit into a voltage signal. The voltage signal is then amplified by the operational amplifier U1. The amplified voltage signal is compared with the reference voltage signal at the inverting input terminal of the voltage comparator U2. When the amplified voltage signal is greater than the reference voltage signal, the output terminal of the voltage comparator U2 outputs a high level, indicating that the equipment has an abnormal working current. The indicator light L then lights up. When the power supply time in the judgment circuit 4 exceeds the preset time, the relay KA will work to disconnect the equipment circuit. The preset time can be changed by replacing the tenth resistor R10 and the second capacitor C2. When the equipment is overloaded, the overload time is greater than the preset time, the relay KA works to disconnect the equipment circuit, and the buzzer BL sounds to remind the workers. When the equipment is briefly overloaded within the tolerable range, the relay KA will not work, and the equipment can continue to work, which is more practical.

[0042] The above shows and describes the basic principle, main features and advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the utility model and are not used to limit the utility model. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, which fall within the scope of the utility model to be protected. The scope of protection of the utility model is defined by the attached claims and their equivalents.

Claims

1. An overload protection circuit for industrial Internet equipment, comprising an amplification circuit (1), a comparison circuit (2), a prompt circuit (3) and a judgment circuit (4), characterized in that: The amplifier circuit (1) is used to sample, convert and amplify the current signal, the comparison circuit (2) is used to determine whether an abnormal voltage occurs, and the determination circuit (4) is used to determine whether an overload condition occurs; The amplifier circuit (1) comprises a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5 and an operational amplifier U1; The first resistor R1 is connected in series in the device circuit, the first end of the second resistor R2 is connected to the first end of the first resistor R1, the second end of the second resistor R2 is connected to the inverting input terminal of the operational amplifier U1, the first end of the third resistor R3 is connected to the second end of the first resistor R1, the second end of the third resistor R3 is connected to the non-inverting input terminal of the operational amplifier U1, the first end of the fourth resistor R4 is grounded, the second end of the fourth resistor R4 is connected to the inverting input terminal of the operational amplifier U1, the first end of the fifth resistor R5 is connected to the non-inverting input terminal of the operational amplifier U1, and the second end of the fifth resistor R5 is connected to the output terminal of the operational amplifier U1; The comparison circuit (2) comprises a voltage comparator U2 and a reference branch; The reference branch includes a reference power supply E, a sixth resistor R6 and a seventh resistor R7, a first end of the sixth resistor R6 is connected to the positive electrode of the reference power supply E, a second end of the sixth resistor R6 is connected to the first end of the seventh resistor R7, and a first end of the seventh resistor R7 is connected to the inverting input end of the voltage comparator U2; The output terminal of the operational amplifier U1 is connected to the non-inverting input terminal of the voltage comparator U2; The prompt circuit (3) comprises an eighth resistor R8 and an indicator light L; A first end of the eighth resistor R8 is connected to the output end of the voltage comparator U2, a first end of the indicator light L is connected to the second end of the eighth resistor R8, and a second end of the indicator light L is grounded; The judgment circuit (4) comprises a 555 timer, a ninth resistor R9, a tenth resistor R10, a switch S, a first capacitor C1, a second capacitor C2, a relay KA and a buzzer BL; A first end of the ninth resistor R9 is connected to the output end of the voltage comparator U2, a second end of the ninth resistor R9 is connected to the third pin of the 555 timer, a first end of the tenth resistor R10 is connected to the output end of the voltage comparator U2, a second end of the tenth resistor R10, the sixth pin of the 555 timer and the seventh pin of the 555 timer are all connected to the first end of the second capacitor C2, a second end of the second capacitor C2 is grounded, a first end of the first capacitor C1 is grounded, a second end of the first capacitor C1 is connected to the fifth pin of the 555 timer, a fourth pin of the 555 timer and the eighth pin of the 555 timer are all connected to the output end of the voltage comparator U2, a first pin of the 555 timer is grounded, a second pin of the 555 timer is connected to the first end of the switch S, a second end of the switch S is grounded, a third pin of the 555 timer is connected to the first end of the relay KA, a second end of the relay KA is connected to the first end of the buzzer BL, a second end of the buzzer BL is grounded, and the relay KA is used to control the circuit disconnection of the device.

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