Overload protection circuit applied to heating equipment

Abstract

The utility model relates to the technical field of overcurrent protection, and discloses an overload protection circuit applied to heating equipment, which is high in safety and reliable, and comprises a switch control module (110), an input detection module (120) and a main control module (130), the input detection module (120) is used for detecting DC electric signals; the main control module (130) is used for acquiring a DC electric signal and outputting a control signal according to the DC electric signal, the output end of the main control module (130) is connected with the control end of the switch control module (110), and the control signal is used for controlling the working state of the switch control module (110).

Description

Technical Field

[0001] This utility model relates to the field of overcurrent protection technology, and more specifically, to an overload protection circuit applied to heating equipment. Background Technology

[0002] Currently, traditional portable heating devices on the market require mechanical buttons or power buttons to start, making the operation process cumbersome. Furthermore, if the design and protection of the heating device are not safe enough, when the device malfunctions (such as overcurrent / overload), it may not only damage the heating device but also cause overheating or spontaneous combustion, potentially resulting in personal injury or property damage to the user.

[0003] Therefore, ensuring the safety and reliability of heating equipment operation has become an urgent problem for those skilled in the art. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a safer and more reliable overload protection circuit for heating equipment, which addresses the shortcomings of the prior art where the heating device is not only damaged when the equipment malfunctions (such as overcurrent / overload), but may also overheat or spontaneously combust.

[0005] The technical solution adopted by this utility model to solve its technical problem is: to construct an overload protection circuit for heating equipment, comprising:

[0006] A switch control module, configured in the overload protection circuit, is used to receive the input voltage signal;

[0007] An input detection module, whose input terminal is connected to the output terminal of the switch control module, is used to detect DC electrical signals;

[0008] A main control module, one input terminal of which is coupled to the output terminal of the input detection module, is used to acquire the DC electrical signal and output a control signal based on the DC electrical signal.

[0009] The output terminal of the main control module is connected to the control terminal of the switch control module, and the control signal is used to control the working state of the switch control module.

[0010] In some implementations, when the input detection module detects the DC electrical signal, the main control module outputs a high-level control signal based on the DC electrical signal to control the switch control module to turn on.

[0011] When the input detection module does not detect the DC electrical signal, the control signal is at a low level to control the switch control module to turn off.

[0012] In some implementations, an overcurrent detection module is also included, which has a voltage threshold.

[0013] The input terminal of the overcurrent detection module is connected to the load circuit terminal to receive current signals and convert the acquired current signals into voltage signals.

[0014] The output of the overcurrent detection module is connected to another input of the main control module.

[0015] The voltage signal is compared with the voltage threshold. When the voltage signal is greater than the voltage threshold, a high-level signal is output.

[0016] The main control module outputs a high-level control signal based on the high-level signal, and the high-level signal is used to control the switch control module to turn off.

[0017] In some embodiments, the overcurrent detection module includes at least an operational amplifier.

[0018] The non-inverting input of the operational amplifier is connected to the load circuit terminal via a seventh resistor.

[0019] The inverting input of the operational amplifier is connected to the common input via an eighth resistor.

[0020] The output of the operational amplifier is coupled to another input of the main control module.

[0021] In some implementations, the main control module includes a main controller.

[0022] One input terminal of the main controller is coupled to the output terminal of the input detection module.

[0023] The other input terminal of the main controller is coupled to the output terminal of the operational amplifier.

[0024] The output terminal of the main controller is connected to the control terminal of the switch control module.

[0025] In some embodiments, the input detection module includes at least a DC plug, a third resistor, and a fourth resistor.

[0026] The first end of the DC plug-in is connected to the output end of the switch control module.

[0027] The second terminal of the DC plug is connected to the non-inverting terminal of the operational amplifier.

[0028] The third terminal of the DC plug is connected to one end of the third resistor and one end of the fourth resistor, respectively.

[0029] The other end of the third resistor is connected to the VCC terminal.

[0030] The other end of the fourth resistor is connected to one input terminal of the main controller.

[0031] In some embodiments, the input detection module further includes a first diode and a second diode connected in parallel.

[0032] The anodes of the first diode and the second diode are connected to the output terminal of the switch control module.

[0033] The cathodes of the first diode and the second diode are connected to the first end of the DC plug.

[0034] In some embodiments, the switch control module includes at least a first MOSFET and a second MOSFET.

[0035] The source of the first MOSFET is connected to the output terminal of the power supply.

[0036] The drain of the first MOSFET is connected to the first terminal of the DC plug.

[0037] The gate of the first MOSFET is connected to the drain of the second MOSFET.

[0038] The gate of the second MOS transistor is connected to the output terminal of the main controller.

[0039] The source of the second MOSFET is connected to the common terminal.

[0040] In some embodiments, the switch control module further includes a first resistor, a second resistor, a fifth resistor, and a sixth resistor.

[0041] The first resistor and the second resistor are connected in parallel.

[0042] The fifth resistor is connected in parallel with the sixth resistor.

[0043] One end of the first resistor is connected to the output terminal of the power supply.

[0044] The other end of the first resistor is connected to one end of the second resistor and the gate of the first MOS transistor.

[0045] The other end of the second resistor is coupled to the drain of the second MOSFET.

[0046] One end of the fifth resistor is connected to the output terminal of the main controller.

[0047] The other end of the fifth resistor is connected to one end of the sixth resistor and the gate of the second MOS transistor, respectively.

[0048] The other end of the sixth resistor is connected to the source and common terminal of the second MOS transistor, respectively.

[0049] In some embodiments, the first MOSFET is selected as a P-channel enhancement-mode MOSFET.

[0050] The second MOSFET is selected as an N-channel enhancement-mode MOSFET.

[0051] The overload protection circuit for heating equipment described in this invention includes a switch control module, an input detection module, and a main control module. The input detection module detects a DC electrical signal; the main control module acquires the DC electrical signal and outputs a control signal based on it. The output terminal of the main control module is connected to the control terminal of the switch control module, and the control signal controls the operating state of the switch control module. Compared with existing technologies, by adding an input detection module to detect the DC electrical signal in real time when a DC power supply is inserted, and by automatically identifying and controlling the on / off state of the switch control module based on the current DC electrical signal, safe control of the heating equipment power supply and portable heating clothing / far-infrared intelligent heating devices can be achieved, thereby ensuring user safety. Attached Figure Description

[0052] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0053] Figure 1 This is a circuit diagram of an embodiment of the overload protection circuit for heating equipment provided by this utility model. Detailed Implementation

[0054] To provide a clearer understanding of the technical features, objectives, and effects of this utility model, the specific embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0055] like Figure 1 As shown, in the first embodiment of the overload protection circuit for heating equipment of this utility model, the overload protection circuit 10 for heating equipment includes a switch control module 110, an input detection module 120, a main control module 130, and an overcurrent detection module 140.

[0056] The switch control module 110 is used to control the on / off state of the DC power supply (corresponding to BATT1) output to the subsequent circuit.

[0057] The input detection module 120 is used to detect the DC electrical signal generated when the DC plug-in J1 is connected to the output terminal of the switch control module 110;

[0058] The main control module 130 has the functions of calculation, signal processing, comparison and output control level;

[0059] The overcurrent detection module 140 has a voltage threshold and functions to compare signals and output a level signal based on the comparison result.

[0060] The overcurrent detection module 140 is used to detect the current signal when the heating load 150 is working, convert the current signal into a voltage signal, compare it with the voltage threshold, and output a level signal (high level or low level) based on the comparison result.

[0061] The heating equipment includes at least a heating load 150 (such as a heating wire) for heating the equipment.

[0062] Specifically, the switch control module 110 is configured in the overload protection circuit to receive the voltage signal input from the DC power supply (corresponding to BATT1);

[0063] The input terminal of the input detection module 120 is connected to the output terminal of the switch control module 110, and is used to detect DC electrical signals and feed the DC electrical signals back to the main control module 130.

[0064] Specifically, one input terminal of the main control module 130 is coupled to the output terminal of the input detection module 120 to acquire DC electrical signals and output control signals (high level or low level) according to the DC electrical signals.

[0065] The output terminal of the main control module 130 is connected to the control terminal of the switch control module 110, and inputs a control signal to the switch control module 110. This control signal is used to control the working state of the switch control module 110.

[0066] Specifically, when the input detection module 120 detects a DC electrical signal, the main control module 130 outputs a high-level control signal based on the DC electrical signal to control the switch control module 110 to turn on.

[0067] That is, when the DC plug is input to the heating device, the third pin of the DC plug J1 is floating and is at a high level. After the main control module 130 detects the low level, the output control signal is at a high level, thereby controlling the switch control module 110 to turn on, so as to realize the intelligent heating device and achieve automatic intelligent detection and heating.

[0068] When the input detection module 120 does not detect a DC electrical signal, the control signal is at a low level. This low-level control signal controls the switch control module 110 to turn off, and the DC power supply (corresponding to BATT1) is turned off.

[0069] In some implementations, to improve the safety of the heating equipment operation, an overcurrent detection module 140 can be installed in the overload protection circuit, which has a voltage threshold.

[0070] The overcurrent detection module 140 has its input terminal connected to the loop terminal of the load 150. It is used to receive the current signal when the load 150 is working and convert the acquired current signal into a voltage signal.

[0071] The output of the overcurrent detection module 140 is connected to another input of the main control module 130.

[0072] The overcurrent detection module 140 compares the acquired voltage signal with a voltage threshold. When the voltage signal is greater than the voltage threshold, it outputs a high-level signal and sends this high-level signal to the main control module 130.

[0073] The main control module 130 outputs a high-level control signal based on the input high-level signal. This high-level signal is used to control the switch control module 110 to turn off, and the DC power supply (corresponding to BATT1) is turned off, thereby disconnecting the power supply to the intelligent heating device to achieve overload current conversion protection.

[0074] In some implementations, to ensure the accuracy of the output level signal, an operational amplifier A101 can be provided in the overcurrent detection module 140, which has the function of signal comparison;

[0075] Specifically, the non-inverting input (corresponding to pin 4) of operational amplifier A101 is connected to the loop terminal of load 150 through resistor R107 to acquire the current signal when load 150 is heating, and then converts the current signal into a voltage signal.

[0076] The inverting input (pin 5) of operational amplifier A101 is connected to the common terminal through resistor R108. The voltage signal at the inverting input (pin 5) of operational amplifier A101 is used as the threshold voltage.

[0077] Among them, a current-limiting resistor RS1 and RS2 are connected in parallel between the non-inverting input (corresponding to pin 4) and the inverting input (corresponding to pin 5) of operational amplifier A101.

[0078] The output terminal (corresponding to pin 6) of the operational amplifier A101 is connected to another input terminal of the main control module 130, and the comparison result of the threshold voltage and the voltage signal is output to the main control module 130.

[0079] In some implementations, in order to improve the reliability of the heating equipment operation, a main controller U101 can be set in the main control module 130, which has the functions of signal processing, calculation and output control signals;

[0080] Specifically, one input terminal (corresponding to pin 2) of the main controller U101 is connected to the output terminal of the input detection module 120, which is used to receive the DC electrical signal generated when the input detection module 120 is connected to the output terminal of the switch control module 110, and output a control signal according to the level state of the DC electrical signal;

[0081] The other input terminal of the main controller U101 (corresponding to pin 3) is coupled to the output terminal of the operational amplifier A101 (corresponding to pin 6) to receive the level signal (high level or low level) output by the operational amplifier A101.

[0082] The output terminal (corresponding to pin 1) of the main controller U101 is connected to the control terminal of the switch control module 110, and outputs a control signal according to the level state of the DC electrical signal or the level signal to control the on / off state of the switch control module 110.

[0083] In some embodiments, the input detection module 120 includes at least a DC plug-in J1, a third resistor R103, and a fourth resistor R104.

[0084] Specifically, the first end of DC plug-in J1 (corresponding to pin 1) is connected to the output end of switch control module 110, the other end of DC plug-in J1 is connected to the input end of load 150, and one input end of DC plug-in J1 is connected to the loop end of load 150.

[0085] The second terminal (pin 2) of DC plug-in J1 is connected to the non-inverting input (pin 4) of operational amplifier A101.

[0086] The third terminal (corresponding to pin 3) of DC plug-in J1 is connected to one end of the third resistor R103 and the fourth resistor R104 respectively.

[0087] The other end of the third resistor R103 is connected to the VCC terminal.

[0088] The other end of the fourth resistor R104 is connected to one input terminal (corresponding to pin 2) of the main controller U101;

[0089] Specifically, by default, pin 3 of DC plug-in J1 is grounded. When DC plug-in J1 is input to the heating device, pin 3 of DC plug-in J1 is floating and is at a high level. After the main controller U101 detects the low level, it outputs a high level to control the switch control module 110 to turn on the intelligent heating device.

[0090] In some embodiments, the input detection module 120 further includes a first diode D101 and a second diode D102 connected in parallel, wherein the anodes of the first diode D101 and the second diode D102 are connected to the output terminal of the switch control module 110.

[0091] The cathodes of the first diode D101 and the second diode D102 are connected to the first terminal (corresponding to pin 1) of the DC plug-in J1. The voltage signal output by the DC power supply (corresponding to BATT1) is input to the load 150 through the switch control module 110 and the DC plug-in J1.

[0092] In some embodiments, the switch control module 110 includes at least a first MOSFET Q101 and a second MOSFET Q102, wherein the first MOSFET Q101 is selected as a P-channel enhancement-mode MOSFET and the second MOSFET Q102 is selected as an N-channel enhancement-mode MOSFET, and each has a switching function;

[0093] Specifically, the source of the first MOSFET Q101 is connected to the output terminal of the power supply (corresponding to BATT1) to receive voltage signals.

[0094] The drain of the first MOSFET Q101 is connected to the first terminal (pin 1) of the DC plug-in J1.

[0095] The gate of the first MOSFET Q101 is connected to the drain of the second MOSFET Q102.

[0096] The gate of the second MOSFET Q102 is connected to the output terminal (pin 1) of the main controller U101.

[0097] The source of the second MOSFET Q102 is connected to the common terminal.

[0098] When the control signal input to the gate of the second MOSFET Q102 of the main controller U101 is low, the second MOSFET Q102 is turned off, the gate level of the first MOSFET Q101 is high, the first MOSFET Q101 is turned off, and there is no voltage signal output.

[0099] When the control signal for the gate of the second MOSFET Q102 input to the main controller U101 is high, the second MOSFET Q102 is turned on, the gate level of the first MOSFET Q101 is pulled to low, the first MOSFET Q101 is turned on, and the voltage signal is input to the load 150 through the source-drain of the first MOSFET Q101 and the first terminal (corresponding to pin 1) of the DC plug-in J1.

[0100] In some embodiments, the switch control module 110 further includes a first resistor R101, a second resistor R102, a fifth resistor R105, and a sixth resistor R106, wherein the first resistor R101 and the second resistor R102 are connected in parallel.

[0101] The fifth resistor R105 and the sixth resistor R106 are connected in parallel.

[0102] One end of the first resistor R101 is connected to the output terminal of the power supply.

[0103] The other end of the first resistor R101 is connected to one end of the second resistor R102 and the gate of the first MOSFET Q101, respectively.

[0104] The other end of the second resistor R102 is coupled to the drain of the second MOSFET Q102.

[0105] One end of the fifth resistor R105 is connected to the output terminal (pin 1) of the main controller U101.

[0106] The other end of the fifth resistor R105 is connected to one end of the sixth resistor R106 and the gate of the second MOSFET Q102.

[0107] The other end of the sixth resistor R106 is connected to the source and common terminal of the second MOSFET Q102.

[0108] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. An overload protection circuit for heating equipment, characterized in that, have: A switch control module, configured in the overload protection circuit, is used to receive the input voltage signal; An input detection module, whose input terminal is connected to the output terminal of the switch control module, is used to detect DC electrical signals; A main control module, one input terminal of which is coupled to the output terminal of the input detection module, is used to acquire the DC electrical signal and output a control signal based on the DC electrical signal. The output terminal of the main control module is connected to the control terminal of the switch control module, and the control signal is used to control the working state of the switch control module.

2. The overload protection circuit for heating equipment according to claim 1, characterized in that, When the input detection module detects the DC electrical signal, the main control module outputs a high-level control signal based on the DC electrical signal to control the switch control module to turn on. When the input detection module does not detect the DC electrical signal, the control signal is at a low level to control the switch control module to turn off.

3. The overload protection circuit for heating equipment according to claim 2, characterized in that, It also includes an overcurrent detection module, which has a voltage threshold. The input terminal of the overcurrent detection module is connected to the load circuit terminal to receive current signals and convert the acquired current signals into voltage signals. The output of the overcurrent detection module is connected to another input of the main control module. The voltage signal is compared with the voltage threshold. When the voltage signal is greater than the voltage threshold, a high-level signal is output. The main control module outputs a high-level control signal based on the high-level signal, and the high-level signal is used to control the switch control module to turn off.

4. The overload protection circuit for heating equipment according to claim 3, characterized in that, The overcurrent detection module includes at least an operational amplifier. The non-inverting input of the operational amplifier is connected to the load circuit terminal via a seventh resistor. The inverting input of the operational amplifier is connected to the common input via an eighth resistor. The output of the operational amplifier is coupled to another input of the main control module.

5. The overload protection circuit for heating equipment according to claim 4, characterized in that, The main control module includes a main controller. One input terminal of the main controller is coupled to the output terminal of the input detection module. The other input terminal of the main controller is coupled to the output terminal of the operational amplifier. The output terminal of the main controller is connected to the control terminal of the switch control module.

6. The overload protection circuit for heating equipment according to claim 5, characterized in that, The input detection module includes at least a DC plug, a third resistor, and a fourth resistor. The first end of the DC plug-in is connected to the output end of the switch control module. The second terminal of the DC plug is connected to the non-inverting terminal of the operational amplifier. The third terminal of the DC plug is connected to one end of the third resistor and one end of the fourth resistor, respectively. The other end of the third resistor is connected to the VCC terminal. The other end of the fourth resistor is connected to one input terminal of the main controller.

7. The overload protection circuit for heating equipment according to claim 6, characterized in that, The input detection module also includes a first diode and a second diode connected in parallel. The anodes of the first diode and the second diode are connected to the output terminal of the switch control module. The cathodes of the first diode and the second diode are connected to the first end of the DC plug.

8. The overload protection circuit for heating equipment according to claim 7, characterized in that, The switch control module includes at least a first MOSFET and a second MOSFET. The source of the first MOSFET is connected to the output terminal of the power supply. The drain of the first MOSFET is connected to the first terminal of the DC plug. The gate of the first MOSFET is connected to the drain of the second MOSFET. The gate of the second MOS transistor is connected to the output terminal of the main controller. The source of the second MOSFET is connected to the common terminal.

9. The overload protection circuit for heating equipment according to claim 8, characterized in that, The switch control module also includes a first resistor, a second resistor, a fifth resistor, and a sixth resistor. The first resistor and the second resistor are connected in parallel. The fifth resistor is connected in parallel with the sixth resistor. One end of the first resistor is connected to the output terminal of the power supply. The other end of the first resistor is connected to one end of the second resistor and the gate of the first MOS transistor. The other end of the second resistor is coupled to the drain of the second MOSFET. One end of the fifth resistor is connected to the output terminal of the main controller. The other end of the fifth resistor is connected to one end of the sixth resistor and the gate of the second MOS transistor, respectively. The other end of the sixth resistor is connected to the source and common terminal of the second MOS transistor, respectively.

10. The overload protection circuit for heating equipment according to claim 9, characterized in that, The first MOSFET is selected as a P-channel enhancement-mode MOSFET. The second MOSFET is selected as an N-channel enhancement-mode MOSFET.

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