Overload warning circuit structure of alternating current

Abstract

The utility model discloses an alternating current overload warning circuit structure, comprising a current detection unit which is electrically connected with a live wire of an alternating current circuit through a live wire first end point and a live wire second end point, the current detection unit detects a working current of the alternating current circuit, and when the magnitude of the working current reaches a preset value, the current detection unit detects the current of the alternating current circuit; the current detection unit sends a detection signal; the control unit is in signal connection with the current detection unit; the warning unit is in signal connection with the control unit, and after the control unit receives the detection signal, the control unit controls the warning unit to give out a warning through a bipolar transistor; and the power supply management unit is electrically connected with a zero line of the alternating current circuit through a zero line end point and provides direct current for the current detection unit, the control unit and the warning unit. Therefore, when the magnitude of the working current reaches the preset value, an alarm can be given out accurately and immediately, and a user is reminded to cut off power in time.

Description

Technical Field

[0001] The utility model relates to an overload warning circuit structure, and in particular to an alternating current overload warning circuit structure which can accurately detect working current and issue a warning in real time when overloaded. Background Art

[0002] In order to prevent the power socket or electrical switch from being damaged due to excessive load, an overload protection device is usually provided on the power socket or electrical switch.

[0003] For example, Taiwan Patent Publication No. M245591 provides an overload protection device for a safety switch, in which a protrusion is provided on the switch button of the safety switch, which presses against the movable contact of the bimetallic strip when the switch is turned on, and a seat is inserted between the two pins of the safety switch. The seat is provided with a protrusion that protrudes into the body and presses against the bimetallic strip when the switch is turned on. When the current is overloaded and the temperature of the bimetallic strip rises and rebounds, the protrusion forms a reaction force to make the bimetallic strip rebound quickly, thereby improving the rebound force and sensitivity of the bimetallic strip.

[0004] However, in the aforementioned patent, when the current is overloaded, the temperature of the bimetallic strip may not have risen yet, and the user cannot immediately know that the current is overloaded, and cannot take corresponding measures in time. Utility Model Content

[0005] Therefore, the purpose of the present invention is to provide an alternating current overload warning circuit structure.

[0006] The utility model provides an alternating current overload warning circuit structure, which is electrically connected to an alternating current circuit. The alternating current overload warning circuit structure comprises: a current detection unit, which is electrically connected to a live wire of the alternating current circuit via a live wire first terminal and a live wire second terminal, the current detection unit detects a working current of the alternating current circuit, and when the magnitude of the working current reaches a preset value, the current detection unit sends a detection signal; a control unit, whose signal is connected to the current detection unit; an alarm unit, whose signal is connected to the control unit, and after the control unit receives the detection signal, the control unit controls the alarm unit to send an alarm; and a power management unit, which is electrically connected to a neutral wire of the alternating current circuit via a neutral wire terminal and electrically connected to the live wire via the live wire first terminal, the power management unit provides a direct current to one or a combination of the current detection unit, the control unit and the alarm unit; and a bipolar transistor, whose base is electrically connected to the control unit, whose emitter is electrically connected to the neutral wire terminal, and whose collector is electrically connected to the alarm unit.

[0007] Furthermore, an operational amplifier is electrically connected to the current detection unit and the control unit. The detection signal is amplified by the operational amplifier and then transmitted to the control unit.

[0008] Wherein, the current detection unit is a Hall current detector.

[0009] Wherein, the warning unit is a sound-generating element and / or a light-emitting element.

[0010] Wherein, the power management unit is a power switch.

[0011] The power management unit is electrically connected to the neutral line terminal via one or a combination of an inductor, a resistor, a capacitor and a diode.

[0012] The live wire is one of the following: a live wire pin, a live wire, a live wire copper sheet, a live wire clip, or a live wire pin of a switch. The neutral wire is one of the following: a neutral wire pin, a neutral wire, a neutral wire copper sheet, a neutral wire clip, or a neutral wire pin of a switch.

[0013] According to the above technical features, the utility model can achieve the following effects:

[0014] 1. The overload warning circuit structure of AC power can be set on a circuit board with an area of ​​less than 3 square centimeters. It is very small and can be easily configured in a plug, socket or electrical appliance.

[0015] 2. The overload warning circuit structure of the alternating current is provided with a first live wire terminal and a second live wire terminal, and the first live wire terminal and the second live wire terminal can be directly connected to the live wire; and a neutral wire terminal is also provided for connecting the neutral wire, so that the magnitude of the working current can be accurately detected.

[0016] 3. Through the combination of the current detection unit, the control unit and the warning unit, an alarm can be accurately issued when the working current reaches a preset value, reminding the user to cut off the power in time.

[0017] 4. Through the operational amplifier, the detection signal of the current detection unit can be amplified, which is convenient for the subsequent control unit to collect the detection signal. At the same time, the operational amplifier can also prevent the inrush current from causing false triggering of the control unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 2 is a circuit diagram of an embodiment of the utility model.

[0019] Figure 2 It is a circuit diagram of the current detection unit and the operational amplifier of the utility model.

[0020] Figure 3 This is a circuit diagram of the control unit of the utility model.

[0021] Figure 4 The utility model is a circuit diagram of a power management unit.

[0022] Figure 5 Schematic diagram of the implementation of the present utility model Figure 1 , indicating that it is combined with a plug.

[0023] Figure 6 Schematic diagram of the implementation of the present utility model Figure 2 , indicating that it is combined with a plug.

[0024] Figure 7 Schematic diagram of the implementation of the present utility model Figure 3 , indicating that it is combined with a socket.

[0025] Figure 8 Schematic diagram of the implementation of the present utility model Figure 4 , indicating that it is combined with a socket.

[0026] Fig. 9 The utility model is a connection diagram of an alternating current overload warning circuit structure configured in a socket in the form of a circuit board.

[0027] Description of reference numerals: 100 - alternating current overload warning circuit structure; 101 - rigid copper bar; 102 - rigid copper bar; 103 - copper wire; 1 - current detection unit; 11, 12, 13, 14, 15, 16, 17, 18 - pins; 2 - control unit; 21, 22, 23, 24, 25, 26, 27, 28 - pins; 3 - warning unit; 4 - power management unit; 41, 42, 43 - pins; 5 - operational amplifier; 51, 52, 53, 54, 55 - pins; 6 - bipolar transistor; 71, 72 -light emitting diode; 200-plug; 201-live pin; 202-neutral pin; 203-live wire; 204-neutral wire; 205,206-wire; 300-socket; 300A-sub-socket; 301-live pin; 302-neutral pin; 303-live wire; 304-neutral wire; 305-live copper sheet; 306-neutral copper sheet; 307-live clip; 308-neutral clip; L-live wire; L1-live first terminal; L2-live second terminal; N-neutral wire; N1-neutral terminal. DETAILED DESCRIPTION

[0028] In view of the above technical features, the main functions of the AC overload warning circuit structure of the present invention can be clearly presented in the following embodiments.

[0029] See also Figure 1 , which discloses an alternating current overload warning circuit structure 100 of the utility model. The alternating current overload warning circuit structure 100 can be configured on a circuit board and electrically connected to an alternating current circuit, such as Figure 6 The plug 200 shown or Figure 8 Socket 300 is shown.

[0030] The AC overload warning circuit structure 100 of the utility model is provided with a live wire first terminal L1, a live wire second terminal L2 and a neutral wire terminal N1. The AC overload warning circuit structure 100 comprises:

[0031] A current detection unit 1, see Figure 1 and Figure 2 The current detection unit 1 of this embodiment is a Hall current detector. Taking the current detection unit 1 of model ACS712 as an example, the current detection unit 1 has eight pins 11, 12, 13, 14, 15, 16, 17, and 18 respectively. Two of the pins 11 and 12 are connected to the first terminal L1 of the live wire, and the other two pins 13 and 14 are connected to the second terminal L2 of the live wire. Pin 15 is grounded. Pin 18 is connected to a DC power. The current detection unit 1 is used to detect the current value of the alternating current. The internal structure of the current detection unit 1 includes a Hall element, a voltage comparator, etc., wherein the Hall element collects the AC signal of the live wire, and then reduces the AC signal through the voltage comparator to become a half-wave AC signal.

[0032] An operational amplifier 5, which is an operational amplifier 5 of model LM321 in this embodiment, has five pins 51, 52, 53, 54, and 55. Pin 53 is connected to pin 17 of the current detection unit 1. Pin 55 is connected to the aforementioned direct current. Pin 52 is grounded. The direct current in this embodiment is 5 volts and 0.1 amperes.

[0033] A control unit 2, see Figure 1 , Figure 2 and Figure 3 , the control unit 2 is connected to the current detection unit 1. Preferably, the control unit 2 is a microcontroller, and the control unit 2 has eight pins 21, 22, 23, 24, 25, 26, 27, 28, wherein the pin 21 is connected to the aforementioned direct current. The pin 27 is connected to the pin 54 of the operational amplifier 5. Two light-emitting diodes 71 and 72 are connected between the pins 22 and 25, wherein the light-emitting diode 71 emits green light when the working current does not reach the preset value, and the light-emitting diode 72 emits red light when the working current reaches the preset value. The pin 26 is connected to the base of a bipolar transistor 6. The present embodiment uses a bipolar transistor 6 of model SS8050, and the emitter of the bipolar transistor 6 is grounded.

[0034] An alarm unit 3 is connected to the DC power. In this embodiment, the alarm unit 3 is connected to the collector of the bipolar transistor 6. Preferably, the alarm unit 3 is a sound element and / or a light element, wherein the sound element is, for example, a buzzer, and the light element is, for example, a light emitting diode.

[0035] The aforementioned light emitting diodes 71, 72 are used to assist in displaying whether the current is overloaded. If the light emitting diodes 71, 72 are not provided, and only the warning unit 3 is used to issue a warning when the current is overloaded, it is also a feasible embodiment.

[0036] A power management unit 4, see Figure 1 and Figure 4 , connecting inductors, resistors, capacitors and diodes, etc. The pin 41 of the power management unit 4 is connected to the first terminal L1 of the live wire, the pin 43 outputs the direct current, and the pin 42 is grounded. Figure 1 In the AC overload warning circuit structure shown, the first live wire terminal L1 and the second live wire terminal L2 are respectively connected to the live wire L of the power source, and the neutral wire terminal N1 is connected to the neutral wire N of the power source.

[0037] The power management unit 4 of this embodiment is a power switch of model FT8430, which outputs a fixed DC current of 5 volts and 0.1 amperes to allow the current detection unit 1, the control unit 2 and the warning unit 3 to operate normally. Figure 1 , Figure 2 , Figure 3 and Figure 4 In the diagram, the grounding symbol represents the connection to the neutral terminal N1.

[0038] See also Figure 1 , Figure 5 and Figure 6 , the AC circuit may be a circuit of a plug 200, wherein the plug 200 includes a live pin 201, a neutral pin 202, a live wire 203, and a neutral wire 204, wherein the live pin 201 and the live wire 203 are both live wires L; the neutral pin 202 and the neutral wire 204 are both neutral wires N. The AC overload warning circuit structure 100 is implemented in the form of a circuit board, wherein the live first terminal L1 is welded to the live pin 201 through a wire 205, and the live second terminal L2 is directly welded to the live wire 203, so that the AC overload warning circuit structure 100 is connected to the live wire L. In addition, the neutral terminal N1 is connected to the neutral wire 204 or the neutral pin 202 through a wire 206, and in this embodiment, the wire 206 is connected to the neutral wire 204.

[0039] See also Figure 1 , Figure 7 and Figure 8 The AC circuit may also be a circuit of a socket 300, for example Figure 7 and Figure 8 The extension cord socket shown, or various types of sockets 300 such as wall sockets, adapter sockets, expansion sockets, etc. The AC overload warning circuit structure 100 of the utility model is electrically connected to the aforementioned socket 300 to detect the overload current of the socket 300 and issue a warning in real time.

[0040] The live wire first end L1 and the live wire second end L2 are connected to the live wire L of the socket. The socket 300 of the present embodiment is an extension cord socket with a plug, and the extension cord socket includes a live wire pin 301, a neutral wire pin 302, a live wire 303, a neutral wire 304, a live wire copper sheet 305, a neutral wire copper sheet 306, a live wire clip 307 and a neutral wire clip 308. The live wire pin 301, the live wire 303, the live wire copper sheet 305 and the live wire clip 307 are connected to each other; the neutral wire pin 302, the neutral wire 304, the neutral wire copper sheet 306 and the neutral wire clip 308 are also connected to each other. The live wire clip 307 is for the live wire pin of the load plug to be inserted, and the neutral wire clip 308 is for the neutral wire pin of the load plug to be inserted. Each live wire clip 307 and a corresponding neutral wire clip 308 form a sub-socket 300A in the above-mentioned socket 300. Figure 8 The live wire L in this embodiment refers to any one of the live wire pin 301, the live wire 303, the live wire copper sheet 305 and the live wire clip 307, and the neutral wire N in this embodiment refers to any one of the neutral wire pin 302, the neutral wire 304, the neutral wire copper sheet 306 and the neutral wire clip 308.

[0041] Some extension cord sockets are also preset with switches, which are not shown in this embodiment. The switch is used to control the conduction and disconnection of the current. For these extension cord sockets with switches, the live wire pin of the switch also belongs to the live wire L described in the utility model. If the switch has a neutral wire pin, the neutral wire pin also belongs to the neutral wire N described in the utility model.

[0042] See also Figure 8 and Fig. 9In the embodiment of the extension cord socket, the overload warning circuit structure 100 of the alternating current is arranged on a circuit board, and the circuit board in the figure omits the related electronic components arranged thereon. The board body of the circuit board is provided with the aforementioned live wire first terminal L1, live wire second terminal L2 and neutral wire terminal N1. A rigid copper strip 101 is used to connect the live wire 303 and the live wire first terminal L1, and another rigid copper strip 102 is used to connect the live wire second terminal L2 and the live wire copper sheet 305, so that the overload warning circuit structure 100 of the alternating current is connected between the live wire 303 and the live wire copper sheet 305 in the live wire L. In addition, a copper wire 103 is used to connect the neutral wire terminal N1 and the neutral wire copper sheet 306, so that the overload warning circuit structure 100 of the alternating current is connected to the neutral wire copper sheet 306 of the neutral wire N. The aforementioned rigid copper strip 101 and rigid copper strip 102 can also be flexible copper wires, and the copper wire 103 can also be a rigid copper strip, and the connection is preferably soldered with solder.

[0043] See also Figure 1 , Figure 6 and Figure 8 Regardless of whether the AC overload warning circuit structure 100 is combined with the socket 300 or the plug 200, the current detection unit 1 will detect a working current on the live wire L. When the working current reaches or exceeds a preset value, for example, reaches or exceeds 16 amperes, the current detection unit 1 will send a detection signal, which is amplified by the operational amplifier 5 and then transmitted to the control unit 2.

[0044] The operational amplifier 5 can amplify the detection signal of the current detection unit 1 to facilitate the subsequent acquisition of the detection signal by the control unit 2. At the same time, the operational amplifier 5 can also prevent the inrush current from causing false triggering of the control unit 2.

[0045] After receiving the detection signal, the control unit 2 controls the warning unit 3 to issue a warning by turning on the bipolar transistor 6, that is, the buzzer sounds. The control unit 2 also directly drives the light emitting diode 72 to emit red light to assist in the warning. When the working current is less than a preset value, such as less than 16 amperes, the control unit 2 controls another light emitting diode 71 to emit green light.

[0046] In actual implementation, the detection signal sent by the current detection unit 1 is a current signal. According to Ohm's law, in combination with the resistance at the output end of the current detection unit 1, the control unit 2 can collect a voltage signal.

[0047] Through the combination of the current detection unit 1, the control unit 2 and the warning unit 3, the warning can be accurately issued when the magnitude of the working current reaches a preset value, reminding the user to cut off the power in time or perform corresponding processing, such as unplugging the plugs of other loads plugged into the extension cord socket at that time, unplugging the plug of the extension cord socket itself, turning off the power switch of the load, etc.

[0048] The ACS712 Hall current detector, LM321 operational amplifier 5, FT8430 power switch, microcontroller and other electronic components with model numbers provided in the above embodiments and drawings, as well as parameters such as current, voltage, and preset values ​​of operating current, are only used to illustrate the implementation of the utility model. The use of other equivalent electronic components and changes in the above parameters are still feasible embodiments of the utility model.

[0049] Based on the description of the above embodiments, the operation, use and effects of the present invention can be fully understood. However, the above embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of implementation of the present invention. That is, simple equivalent changes and modifications made according to the claims of the present invention and the contents of the utility model specification are all within the scope of the present invention.

Claims

1. An alternating current overload warning circuit structure, electrically connected to an alternating current circuit, characterized in that: The AC overload warning circuit structure includes: a current detection unit, electrically connected to a live wire of the AC circuit via a live wire first terminal and a live wire second terminal, the current detection unit detecting a working current of the AC circuit, and sending a detection signal when the working current reaches a preset value; a control unit, signal-connected to the current detection unit; An alarm unit, the signal of which is connected to the control unit, so that after the control unit receives the detection signal, the control unit controls the alarm unit to issue an alarm; a power management unit, electrically connected to a neutral line of the AC circuit via a neutral line terminal, and electrically connected to the live line via the live line first terminal, the power management unit providing a DC power to the current detection unit, the control unit and the warning unit; as well as A bipolar transistor, wherein the base of the bipolar transistor is electrically connected to the control unit, the emitter is electrically connected to the zero line terminal, and the collector is electrically connected to the warning unit.

2. The AC overload warning circuit structure according to claim 1, characterized in that: An operational amplifier is electrically connected to the current detection unit and the control unit. The detection signal is amplified by the operational amplifier and then transmitted to the control unit.

3. The AC overload warning circuit structure according to claim 1, characterized in that: The current detection unit is a Hall current detector.

4. The AC overload warning circuit structure according to claim 1, characterized in that: The warning unit is a sound-generating element and / or a light-emitting element.

5. The AC overload warning circuit structure according to claim 1, characterized in that: The power management unit is a power switch.

6. The AC overload warning circuit structure according to claim 1, characterized in that: The power management unit is electrically connected to the neutral line terminal via one or a combination of an inductor, a resistor, a capacitor and a diode.

7. The AC overload warning circuit structure according to claim 1, characterized in that: The live wire is one of the following: a live wire pin, a live wire, a live wire copper sheet, a live wire clip, or a live wire pin of a switch; the neutral wire is one of the following: a neutral wire pin, a neutral wire, a neutral wire copper sheet, a neutral wire clip, or a neutral wire pin of a switch.

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