A load heating control protection circuit, device
Patent Information
- Application Number
- CN202522196204.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-17
- Publication Date
- 2026-10-09
- Estimated Expiration
- 2035-10-17
AI Technical Summary
[0005]为解决现有技术存在不能及时切断加热的问题，本实用新型提出一种负载加热控制保护电路、装置，在主控芯片失效时，及时切断负载加热电路，保证用电安全
本实用新型提出一种负载加热控制保护电路、装置，利用MCU作为信号源模块的两个信号输出端分别连接加热保护模块与第二加热控制模块，加热保护模块和第二加热控制模块的另一端分别连接加课控制模块中的继电器的第一端和第二端；需要加热时，MCU发出控制信号控制第二加热控制模块使第一加热控制模块的继电器闭合，连接继电器第三端的加热负载接通电源火线进行加热；当MCU失效时，加热保护模块断电，第一加热控制模块的继电器立刻断开，加热负载停止加热，保证了用电安全。
Smart Images
Figure CN224843103U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of protection circuit design, and in particular to a load heating control protection circuit and device. Background Technology
[0002] Under abnormal conditions such as short circuits or aging, the heating element may overheat and cause a fire. Similarly, if the main control chip is damaged or fails due to abnormal conditions, and the power supply cannot be cut off in time, a dangerous situation may occur. Therefore, designing a load heating protection circuit is of great significance for the safe use of heating equipment.
[0003] Currently, load heating protection circuits are mainly designed based on two aspects: overcurrent protection and overtemperature protection. Overcurrent protection detects the current through fuses or circuit breakers. When the current exceeds a set threshold, it triggers the protection to cut off the power and stop heating. Overtemperature protection detects the temperature through temperature sensors or thermistors. When the temperature exceeds a set threshold, it triggers the protection to stop heating.
[0004] Existing technology proposes a heating protection circuit, including a heating control terminal, an optocoupler, and a MOSFET. The heating software control terminal is connected to the MOSFET via the optocoupler, and the output terminal of the MOSFET is connected to the nozzle. The circuit also includes a capacitor, one end of which is connected to one pin of the optocoupler's input terminal, and the other end is connected to the heating control terminal. In the event of a malfunction in the heating control terminal, the nozzle heating drive protection circuit utilizes the capacitor's AC-passing and DC-blocking characteristics to reduce the nozzle heating drive voltage, thereby stopping the nozzle heating and preventing damage from prolonged heating. However, the capacitor's DC-blocking effect relies on its discharge process to gradually reduce the optocoupler's input current. If the capacitor's capacitance is too large and the discharge time is too long, the protection circuit may act lagily, failing to cut off heating in time before the nozzle overheats, still posing a risk of temporary overheating. Summary of the Invention
[0005] To address the problem of existing technologies failing to promptly cut off heating, this invention proposes a load heating control and protection circuit and device that promptly cuts off the load heating circuit in the event of a main control chip failure, ensuring electrical safety.
[0006] To achieve the above-mentioned technical effects, the technical solution of this utility model is as follows: In a first aspect, this application proposes a load heating control and protection circuit, comprising: a signal source module, a heating protection module, a first heating control module, and a second heating control module; The first output terminal of the signal source module is connected to the input terminal of the heating protection module, the output terminal of the heating protection module is connected to the first terminal of the first heating control module, the second terminal of the first heating control module is connected to the first terminal of the second heating control module, and the second terminal of the second heating control module is connected to the second output terminal of the signal source module.
[0007] Preferably, the signal source module and the heating protection module are powered by an external power source.
[0008] Preferably, the signal source module includes a capacitor C3 and an MCU, wherein one end of the capacitor C3 and the MCU pin VCC are both connected to an external power supply, and the other end of the capacitor C3 and the MCU pin VSS are both grounded.
[0009] Preferably, the heating protection module includes capacitors C1 and C2, resistors R1, R2, R3, and R4, diodes D1 and D2, and transistors Q1 and Q2; One end of capacitor C2 serves as the input terminal of the heating protection module and is connected to the first output terminal of the signal source module (1). The other end of capacitor C2 is connected to the anode of diode D1 and the cathode of diode D2. The cathode of diode D1 is connected to one end of resistor R3 and one end of capacitor C1. The other end of capacitor C1 and the anode of diode D2 are both grounded. The other end of resistor R3 is connected to the base of transistor Q2 and one end of resistor R4. One end of resistor R4 is connected to the emitter of transistor Q2 and then grounded. The collector of transistor Q2 is connected to one end of resistor R2. The other end of resistor R2 is connected to one end of resistor R1 and the gate of transistor Q1. The source of transistor Q1 serves as the input terminal of the heating protection module and is connected to an external power supply. The other end of resistor R1 is connected to the drain of transistor Q1. The drain of transistor Q1 serves as the output terminal of the heating protection module and is connected to the first heating control module.
[0010] Preferably, all external power sources are... DC voltage source.
[0011] Preferably, the first heating control module includes a relay K1, the first end of the relay K1 serves as the first end of the first heating control module, the second end of the relay K1 serves as the second end of the first heating control module, the third end of the relay K1 is connected to the heating load U2, and the fourth end of the relay K1 is connected to the power supply live wire ACL.
[0012] Preferably, the second heating control module includes transistor Q3 and resistors R5 and R6; The emitter of transistor Q3 serves as the first terminal of the second heating control module. The collector of transistor Q3 and one end of resistor R6 are both grounded. The base of transistor Q3 is connected to the other end of resistor R6 and one end of resistor R5, respectively. The other end of resistor R5 serves as the second terminal of the second heating control module and is connected to the second output terminal of the signal source module.
[0013] Preferably, transistor Q1 is a metal-semiconductor field-effect transistor (MOSFET), and transistor Q2 is a bipolar junction transistor (BJT).
[0014] Preferably, the transistor Q3 is a bipolar junction transistor (BJT).
[0015] Secondly, this application also proposes a load heating control and protection device, the device comprising a signal source module, a heating protection module, a first heating control module, and a second heating control module; The first output terminal of the signal source module is connected to the input terminal of the heating protection module, the output terminal of the heating protection module is connected to the first terminal of the first heating control module, the second terminal of the first heating control module is connected to the first terminal of the second heating control module, and the second terminal of the second heating control module is connected to the second output terminal of the signal source module.
[0016] Compared with the prior art, the beneficial effects of this utility model's technical solution are: This utility model proposes a load heating control and protection circuit and device. An MCU is used as the signal source module, with its two signal output terminals connected to a heating protection module and a second heating control module, respectively. The other ends of the heating protection module and the second heating control module are connected to the first and second terminals of a relay in the heating control module, respectively. When heating is required, the MCU sends a control signal to control the second heating control module to close the relay in the first heating control module, connecting the heating load connected to the third terminal of the relay to the power supply wire for heating. When the MCU fails, the heating protection module is powered off, the relay in the first heating control module immediately disconnects, and the heating load stops heating, ensuring electrical safety. Attached Figure Description
[0017] Figure 1 This is a schematic diagram of the structure of a load heating control and protection circuit proposed in Embodiment 1 of this utility model; Figure 2 This is another structural schematic diagram of a load heating control and protection circuit proposed in Embodiment 2 of this utility model.
[0018] Figure 3 This is a schematic diagram showing the specific structure of the signal source module proposed in Embodiment 2 of this utility model; Figure 4 This is a schematic diagram showing the specific structure of the heating protection module proposed in Embodiment 2 of this utility model; Figure 5 This is a schematic diagram showing the specific structure of the first heating control module proposed in Embodiment 2 of this utility model; Figure 6 This is a schematic diagram showing the specific structure of the second heating control module proposed in Embodiment 2 of this utility model.
[0019] 1. Signal source module; 2. Heating protection module; 3. First heating control module; 4. Second heating control module. Detailed Implementation
[0020] The accompanying drawings are for illustrative purposes only and should not be construed as limiting the scope of this patent. To better illustrate this embodiment, some parts of the accompanying drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions; It is understandable to those skilled in the art that some well-known details may be omitted from the accompanying drawings.
[0021] The technical solution of this utility model will be further described below with reference to the accompanying drawings and embodiments.
[0022] The positional relationships depicted in the accompanying drawings are for illustrative purposes only and should not be construed as limiting this patent. Example 1 This embodiment proposes a load heating control and protection circuit, the schematic diagram of which is shown below. Figure 1 As shown, it includes: signal source module 1, heating protection module 2, first heating control module 3, and second heating control module 4; The first output terminal of the signal source module 1 is connected to the input terminal of the heating protection module 2, the output terminal of the heating protection module 2 is connected to the first terminal of the first heating control module 3, the second terminal of the first heating control module 3 is connected to the first terminal of the second heating control module 4, the third terminal of the first heating control module 3 is connected to the heating load, and the second terminal of the second heating control module 4 is connected to the second output terminal of the signal source module 1.
[0023] In this embodiment, the two signal output terminals of the MCU as the signal source module are respectively connected to the heating protection module and the second heating control module. The other ends of the heating protection module and the second heating control module are respectively connected to the first terminal and the second terminal of the heating control module. When the MCU is working normally, the MCU can actively send control signals to control the second heating control module to connect the heating load of the first heating control module to the power wire for heating. When the MCU fails, the heating protection module is powered off, the relay of the first heating control module is immediately disconnected, and the heating load stops heating, ensuring electrical safety.
[0024] Example 2 This embodiment presents another structural schematic diagram of the load heating control and protection circuit, as shown below. Figure 2 As shown.
[0025] In this embodiment, the signal source module 1 and the heating protection module 2 are powered by an external power source.
[0026] Specifically, see Figure 2 The external power supply is connected to the power supply port of the signal source module 1 and the source of the transistor Q1 in the heating protection module 2.
[0027] In this embodiment, the signal source module 1 includes a capacitor C3 and an MCU. One end of the capacitor C3 and the VCC pin of the MCU are connected to an external power supply, and the other end of the capacitor C3 and the VSS pin of the MCU are grounded.
[0028] Specifically, the MCU chip is a BF7615CM20 chip. An external power supply provides power to the MCU through its VCC pin. Capacitor C3 is used to provide a clean and stable power supply voltage to the MCU, preventing MCU malfunctions due to voltage fluctuations and noise interference. .
[0029] In this embodiment, the heating protection module 2 includes capacitors C1 and C2, resistors R1, R2, R3, and R4, diodes D1 and D2, and transistors Q1 and Q2; a schematic diagram of the specific structure of the heating protection module 2 is shown below. Figure 4 As shown, One end of capacitor C2 serves as the input terminal of heating protection module 2, connected to the first output terminal of signal source module 1. The other end of capacitor C2 is connected to the anode of diode D1 and the cathode of diode D2. The cathode of diode D1 is connected to one end of resistor R3 and one end of capacitor C1. The other end of capacitor C1 and the anode of diode D2 are both grounded. The other end of resistor R3 is connected to the base of transistor Q2 and one end of resistor R4. One end of resistor R4 is connected to the emitter of transistor Q2 and then grounded. The collector of transistor Q2 is connected to one end of resistor R2. The other end of resistor R2 is connected to one end of resistor R1 and the gate of transistor Q1. The source of transistor Q1 serves as the input terminal of heating protection module 2, connected to an external power supply. The other end of resistor R1 is connected to the drain of transistor Q1. The drain of transistor Q1 serves as the output terminal of heating protection module 2, connected to the first heating control module 3.
[0030] Specifically, the transistor Q1 is model SI2301, and the resistor R1 is 20Ω. The surface mount resistor, R2 is 1. The resistor; the transistor Q2 is model S8050, and the resistor... ,resistance ,capacitance The capacitor C1 requires a 50V voltage connection. Diodes D1 and D2 are both IN4148. The capacitor C5 requires a voltage of 50V to be applied across its terminals.
[0031] In this embodiment, all external power sources are DC voltage source.
[0032] Specifically, the The DC voltage sources are connected to the source of transistor Q1 and the VCC pin of the MCU, respectively.
[0033] In this embodiment, the first heating control module 3 includes a relay K1. The first terminal of the relay K1 serves as the first terminal of the first heating control module 3, the second terminal of the relay K1 serves as the second terminal of the first heating control module 3, the third terminal of the relay K1 is connected to the heating load U2, and the fourth terminal of the relay K1 is connected to the power supply live wire ACL. A detailed structural diagram of the first heating control module 3 is shown below. Figure 5 As shown.
[0034] Specifically, the relay K1 is model MPF-105-A-2 with a rated input power of 0.2W, and the power range of the heating load is 50W~1800W.
[0035] In this embodiment, the second heating control module 4 includes transistor Q3 and resistors R5 and R6; The emitter of transistor Q3 serves as the first terminal of the second heating control module 4. The collector of transistor Q3 and one end of resistor R6 are both grounded. The base of transistor Q3 is connected to the other end of resistor R6 and one end of resistor R5. The other end of resistor R5 serves as the second terminal of the second heating control module 4 and is connected to the second output terminal of the signal source module. A schematic diagram of the specific structure of the second heating control module 4 is shown below. Figure 6 As shown.
[0036] Specifically, the transistor Q3 is an S8050, and the resistor R5 is... Surface mount resistors, resistors .
[0037] In this embodiment, transistor Q1 is a metal-semiconductor field-effect transistor (MOSFET), and transistor Q2 is a bipolar junction transistor (BJT).
[0038] In this embodiment, transistor Q3 is a bipolar junction transistor (BJT).
[0039] Example 3 This embodiment proposes a load heating control and protection device. In this embodiment, the device includes the load heating control and protection circuit structure described in Embodiment 1 or Embodiment 2, and also includes a housing for mounting the circuit structure.
[0040] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating this utility model, and are not intended to limit the implementation of this utility model. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.
Claims
1. A load heating control and protection circuit, characterized in that, include: Signal source module (1), heating protection module (2), first heating control module (3), second heating control module (4); The first output terminal of the signal source module (1) is connected to the input terminal of the heating protection module (2), the output terminal of the heating protection module (2) is connected to the first terminal of the first heating control module (3), the second terminal of the first heating control module (3) is connected to the first terminal of the second heating control module (4), the third terminal of the first heating control module (3) is connected to the heating load, and the second terminal of the second heating control module (4) is connected to the second output terminal of the signal source module (1).
2. The load heating control and protection circuit according to claim 1, characterized in that, The signal source module (1) and the heating protection module (2) are powered by an external power source.
3. The load heating control and protection circuit according to claim 2, characterized in that, The signal source module (1) includes a capacitor C3 and an MCU. One end of the capacitor C3 and the MCU pin VCC are connected to an external power supply, and the other end of the capacitor C3 and the MCU pin VSS are grounded.
4. The load heating control and protection circuit according to claim 1, characterized in that, The heating protection module (2) includes capacitors C1 and C2, resistors R1, R2, R3 and R4, diodes D1 and D2, and transistors Q1 and Q2; One end of capacitor C2 serves as the input terminal of the heating protection module (2) and is connected to the first output terminal of the signal source module (1). The other end of capacitor C2 is connected to the anode of diode D1 and the cathode of diode D2. The cathode of diode D1 is connected to one end of resistor R3 and one end of capacitor C1. The other end of capacitor C1 and the anode of diode D2 are both grounded. The other end of resistor R3 is connected to the base of transistor Q2 and one end of resistor R4. One end of resistor R4 is connected to the emitter of transistor Q2 and then grounded. The collector of transistor Q2 is connected to one end of resistor R2. The other end of resistor R2 is connected to one end of resistor R1 and the gate of transistor Q1. The source of transistor Q1 serves as the input terminal of the heating protection module (2) and is connected to an external power supply. The other end of resistor R1 is connected to the drain of transistor Q1. The drain of transistor Q1 serves as the output terminal of the heating protection module (2) and is connected to the first heating control module (3).
5. The load heating control and protection circuit according to any one of claims 2 to 4, characterized in that, The external power sources are all DC voltage source.
6. The load heating control and protection circuit according to claim 1, characterized in that, The first heating control module (3) includes a relay K1. The first end of the relay K1 serves as the first end of the first heating control module (3) and is connected to the output end of the heating protection module (2). The second end of the relay K1 serves as the second end of the first heating control module (3) and is connected to the first end of the second heating control module (4). The third end of the relay K1 is connected to the heating load U2, and the fourth end of the relay K1 is connected to the power supply live wire ACL.
7. The load heating control and protection circuit according to claim 1, characterized in that, The second heating control module (4) includes transistor Q3 and resistors R5 and R6; The emitter of transistor Q3 serves as the first terminal of the second heating control module (4). The collector of transistor Q3 and one end of resistor R6 are both grounded. The base of transistor Q3 is connected to the other end of resistor R6 and one end of resistor R5 respectively. The other end of resistor R5 serves as the second terminal of the second heating control module (4) and is connected to the second output terminal of the signal source module (1).
8. The load heating control and protection circuit according to claim 4, characterized in that, The transistor Q1 is a metal-semiconductor field-effect transistor (MOSFET), and the transistor Q2 is a bipolar junction transistor (BJT).
9. The load heating control and protection circuit according to claim 7, characterized in that, The transistor Q3 is a bipolar junction transistor (BJT).
10. A load heating control and protection device, characterized in that, The device includes the load heating control and protection circuit as described in any one of claims 1 to 9.