Automatic heating temperature control circuit and heating equipment thereof

Abstract

The utility model discloses an automatic heating temperature control circuit and heating equipment thereof, and relates to the technical field of control circuits. The circuit comprises an input circuit, a voltage division control circuit, a signal processing module and a working circuit, the signal processing module is used for comparing signals from the input circuit and the voltage division control circuit and outputting a control signal, the input circuit is used for outputting a reference voltage signal, the voltage division control circuit is used for outputting a comparison voltage signal, and the working circuit is used for outputting the comparison voltage signal. And the working circuit is used for driving a load to work according to the output signal of the signal processing module. According to the embodiment of the utility model, the signal processing module is utilized to compare voltage signals provided by the input circuit and the voltage division control circuit, so that the circuit can automatically adjust the working state of the load and realize accurate temperature control, thereby not only simplifying the hardware requirement and reducing the production cost, but also reducing the dependence on complex software support, and improving the reliability of the circuit. And the complexity and the cost of technical maintenance are reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of control circuits, in particular to an automatic heating temperature control circuit and a heating device thereof. Background Art

[0002] The application of controlled heating technology has become increasingly common in modern industrial and household appliances. The core of controlled heating technology is to achieve temperature stability and regulation by precisely controlling the operation of heating elements, ensuring the efficiency and safety of the heating process. For example, in household appliances such as electric water heaters and microwave ovens, the heating system is controlled to ensure uniformity and energy saving of water or food heating.

[0003] However, most of its implementations rely on high-cost microcontrollers or application-specific integrated circuits. These solutions usually require complex software support to perform precise temperature control and monitoring functions. For example, in smart home appliances and precision manufacturing equipment, not only are the hardware costs high, but the development and maintenance of the corresponding control software also requires expertise and continuous technical support. Its high cost and complexity remain the main obstacles to its wider application. Utility Model Content

[0004] The purpose of the present utility model is to address the defects and shortcomings of the existing technology. On the one hand, it provides an automatic heating temperature control circuit, including an input circuit, a voltage divider control circuit, a signal processing module and a working circuit, wherein the input circuit is connected to the first input end of the signal processing module, the voltage divider control circuit is connected to the second input end of the signal processing module, and the working circuit is connected to the first output end of the signal processing module. The signal processing module is used to compare the signals from the input circuit and the voltage divider control circuit and output a control signal. The input circuit is used to output a reference voltage signal, the voltage divider control circuit is used to output a comparison voltage signal, and the working circuit is used to drive a load to work according to the output signal of the signal processing module.

[0005] The voltage divider control circuit includes a voltage divider submodule and a temperature sensing module. One end of the temperature sensing module is grounded, and the other end is connected to one end of the voltage divider submodule to form a common end. The other end of the voltage divider submodule is connected to the power supply end. The second input end of the signal processing module is connected to the common end. The power supply end is grounded through the voltage divider submodule and the temperature sensing module to form a loop.

[0006] The input voltage of the second input terminal of the signal processing module is the divided voltage of the temperature sensing module at the power supply terminal.

[0007] The temperature sensing module includes a temperature sensing resistor NTC1 , one end of which is grounded, and the other end of which is connected to the voltage divider module.

[0008] The voltage divider submodule includes a first resistor R7, a second resistor R8, a third resistor R9, a fourth resistor R10, a fifth resistor R11, a sixth resistor R12, and a rotary switch SW1. The rotary switch SW1 includes a first contact, a second contact, a third contact, a fourth contact, a fifth contact, a sixth contact, a seventh contact, and a selection contact. One end of the selection contact is connected to the power supply end, and the other end is connected to any one of the first contact, the second contact, the third contact, the fourth contact, the fifth contact, the sixth contact, and the seventh contact. The first contact is floating. The second contact and the first resistor R7 are connected in series to the common end. The third contact and the second resistor R8 are connected in series to the common end. The fourth contact and the third resistor R9 are connected in series to the common end. The fifth contact and the fourth resistor R10 are connected in series to the common end. The sixth contact and the fifth resistor R11 are connected in series to the common end. The seventh contact and the sixth resistor R12 are connected in series to the common end.

[0009] The voltage divider module includes a variable resistor RP1, a sliding end of the variable resistor RP1 is connected to the power supply end, a first fixed end of the variable resistor RP1 is connected to the voltage divider module and the second input end of the signal processing module, and a second fixed end of the variable resistor RP1 is suspended.

[0010] A seventh resistor is further provided between the second input terminal of the signal processing module and the common terminal.

[0011] The working circuit includes an eighth resistor R3, a ninth resistor R5, a switch tube Q1 and a heating interface CN1. One end of the eighth resistor R3 is connected to the first output end of the signal processing module, the other end of the eighth resistor R3 is connected to one end of the ninth resistor R5 and the gate of the switch tube Q1, the other end of the ninth resistor R5 is connected to the source of the switch tube Q1 and the ground end, the drain of the switch tube Q1 is connected to the first port of the heating interface CN1, and the second port of the heating interface CN1 is connected to the power supply end.

[0012] The input circuit includes a tenth resistor R1, an eleventh resistor R2 and a twelfth resistor R4, one end of the tenth resistor R1 is connected to the power supply end, the other end of the tenth resistor R1 is connected to one end of the eleventh resistor R2 and one end of the twelfth resistor R4, the other end of the twelfth resistor R4 is grounded, and the other end of the eleventh resistor R2 is connected to the first input end of the signal processing module.

[0013] On the other hand, the present invention also provides a heating device, including the automatic heating temperature control circuit of the above technical solution.

[0014] The embodiment of the utility model utilizes a signal processing module to compare the voltage signals provided by the input circuit and the voltage divider control circuit. The circuit can automatically adjust the working state of the load to achieve precise temperature control, which not only simplifies hardware requirements and reduces production costs, but also reduces dependence on complex software support and reduces the complexity and cost of technical maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0016] Figure 1 It is a structural block diagram of the first embodiment of the utility model;

[0017] Figure 2 is a circuit diagram of another embodiment of the utility model;

[0018] Figure 3 It is a circuit diagram of another embodiment of the present utility model.

[0019] Figure 4 It is a circuit diagram of yet another embodiment of the present utility model.

[0020] Reference numerals:

[0021] DETAILED DESCRIPTION

[0022] The present invention will be described in further detail below with reference to the accompanying drawings.

[0023] This specific embodiment is merely an explanation of the present invention and is not a limitation of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed, but as long as they are within the scope of the claims of the present invention, they are protected by patent law.

[0024] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0025] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are also within the scope of protection of the present invention.

[0026] 1 , the present invention provides an automatic heating temperature control circuit, comprising an input circuit 100, a voltage divider control circuit 200, a signal processing module 300, and a working circuit 400. The input circuit 100 is connected to a first input end of the signal processing module 300, the voltage divider control circuit 200 is connected to a second input end of the signal processing module 300, the working circuit 400 is connected to a first output end of the signal processing module 300, the signal processing module 300 is used to compare signals from the input circuit 100 and the voltage divider control circuit 200, and output a control signal. The input circuit 100 is used to output a reference voltage signal, the voltage divider control circuit 200 is used to output a comparison voltage signal, and the working circuit 400 is used to drive a load to operate according to the output signal of the signal processing module 300.

[0027] Specifically, the input circuit 100 is responsible for providing a reference voltage signal, which is used as a reference point for temperature control. The voltage divider control circuit 200 generates a comparison voltage signal, which is obtained by voltage division by a temperature sensing element such as a thermistor, reflecting the current temperature state of the system. The signal processing module 300 receives the reference voltage from the input circuit 100 and the comparison voltage from the voltage divider control circuit 200. The signal processing module compares the two voltage signals and generates a control signal based on the comparison result. If the comparison voltage is lower than the reference voltage, the signal processing module outputs an activation signal. If it is higher than or equal to, it outputs a stop or hold signal. Finally, the working circuit 400 controls the opening or closing of the heating element according to the output signal of the signal processing module 300.

[0028] The embodiment of the utility model utilizes a signal processing module to compare the voltage signals provided by the input circuit and the voltage divider control circuit. The circuit can automatically adjust the working state of the load to achieve precise temperature control, which not only simplifies hardware requirements and reduces production costs, but also reduces dependence on complex software support and reduces the complexity and cost of technical maintenance.

[0029] Reference Figure 2 , the utility model provides another automatic heating temperature control circuit:

[0030] Specifically, the voltage divider control circuit 200 includes a voltage divider sub-module 210 and a temperature sensing module 220. One end of the temperature sensing module 220 is grounded, and the other end is connected to one end of the voltage divider sub-module 210 to form a common end. The other end of the voltage divider sub-module 210 is connected to the power supply end. The second input end of the signal processing module 300 is connected to the common end. The power supply end is grounded through the voltage divider sub-module 210 and the temperature sensing module 220 to form a loop.

[0031] Furthermore, the input voltage of the second input terminal of the signal processing module 300 is the divided voltage of the temperature sensing module 220 at the power supply terminal.

[0032] Specifically, the voltage divider submodule 210 and the temperature sensing module 220 form a voltage divider loop, wherein the resistance value of the temperature sensing module 220 changes with temperature, thereby adjusting the voltage divider passing through it. The second input end of the signal processing module 300 is connected to the common end of the voltage divider control circuit, and receives the divided voltage formed by the temperature sensing module 220 and the voltage divider submodule 210 (this divided voltage reflects the temperature of the current environment or system), and the signal processing module 300 compares the divided voltage from the voltage divider control circuit with a preset reference voltage. If the divided voltage is lower than the reference voltage, the signal processing module generates an activation signal to turn on the heating. If the divided voltage is higher than or equal to the reference voltage, a stop signal is generated to turn off the heating. Finally, the output signal of the signal processing module is used to control the working circuit 400, that is, the turning on or off of the heating element, thereby automatically adjusting the system temperature to ensure that it remains within the set temperature range.

[0033] This embodiment utilizes the temperature-dependent resistance of the temperature-sensing module, combined with the voltage divider module. The circuit can accurately generate a voltage divider that reflects the current temperature. The signal processing module evaluates this voltage divider against a preset reference voltage and controls the heating element on or off accordingly, thereby automatically adjusting and maintaining the system temperature within a set range. This improves the system's response speed and energy efficiency while reducing energy consumption.

[0034] Reference Figure 3 , the utility model provides another automatic heating temperature control circuit:

[0035] Specifically, the temperature sensing module 220 includes a temperature sensing resistor NTC1, one end of which is grounded and the other end is connected to the voltage divider submodule 210. The resistance of NTC1 changes with temperature, and together with the voltage divider submodule 210, it forms a voltage divider loop, which can accurately output a voltage signal representing the actual temperature, so that the signal processing module can more accurately control the working state of the heating element and effectively maintain the system within a preset temperature range, thereby improving energy efficiency and ensuring the uniformity and safety of the heating process.

[0036] Furthermore, the voltage divider submodule 210 includes a variable resistor RP1, the sliding end of the variable resistor RP1 is connected to the power supply end, the first fixed end of the variable resistor RP1 is connected to the voltage divider submodule 210 and the second input end of the signal processing module 300, and the second fixed end of the variable resistor RP1 is suspended. By connecting the sliding end of RP1 to the power supply end and its first fixed end to the voltage divider submodule 210 and the second input end of the signal processing module 300, the user or the system is allowed to adjust the voltage division ratio as needed. This adjustability allows the circuit to flexibly respond to different temperature control requirements, thereby improving the system's response speed and accuracy to temperature changes.

[0037] Furthermore, a seventh resistor R6 is provided between the second input terminal of the signal processing module 300 and the common terminal. R6 acts as a current-limiting resistor, primarily limiting the current flowing through this path, thereby preventing damage to the input terminal of the signal processing module due to excessive current. This protective measure ensures circuit stability and component safety. Furthermore, the design of R6 does not alter the voltage level at its connection point, meaning it does not affect the voltage at the second input port (negative input terminal V+) of the signal processing module 300.

[0038] Furthermore, the working circuit 400 includes an eighth resistor R3, a ninth resistor R5, a switch tube Q1, and a heating interface CN1. One end of the eighth resistor R3 is connected to the first output end of the signal processing module 300, the other end of the eighth resistor R3 is connected to one end of the ninth resistor R5 and the gate of the switch tube Q1, the other end of the ninth resistor R5 is connected to the source and ground of the switch tube Q1, the drain of the switch tube Q1 is connected to the first port of the heating interface CN1, and the second port of the heating interface CN1 is connected to the power supply end. The working circuit 400 adopts a switch tube Q1 (field effect transistor) and the eighth resistor R3 and the ninth resistor R5 that cooperate with it form an effective switching control mechanism. The eighth resistor R3 and the ninth resistor R5 work together to provide appropriate bias and current limiting protection for the switch tube Q1, ensuring that Q1 can be safely and reliably turned on or off when receiving the output signal of the signal processing module 300. Q1, as the core switching component, directly controls the heating load connected to the heating interface CN1. The efficient switching capability of Q1 enables the circuit to respond quickly to the control signal and accurately control the working state of the heating element, thereby achieving fast and efficient temperature regulation.

[0039] Furthermore, the input circuit 100 includes a tenth resistor R1, an eleventh resistor R2, and a twelfth resistor R4, one end of the tenth resistor R1 is connected to the power supply end, the other end of the tenth resistor R1 is connected to one end of the eleventh resistor R2 and one end of the twelfth resistor R4, the other end of the twelfth resistor R4 is grounded, and the other end of the eleventh resistor R2 is connected to the first input end of the signal processing module 300. The input circuit 100 constructs an effective voltage divider network by combining the tenth resistor R1, the eleventh resistor R2, and the twelfth resistor R4. The design purpose of this network is to provide a stable and accurate reference voltage to the first input end of the signal processing module 300. The tenth resistor R1 and the twelfth resistor R4 form a voltage divider to reduce the voltage at the power supply end to an appropriate level, and the eleventh resistor R2 imports this reduced voltage into the signal processing module, ensuring that the signal processing module can receive an accurate reference voltage, thereby effectively comparing it with the comparison voltage output by the voltage divider control circuit 200. This embodiment not only improves the accuracy of the entire control system, but also enhances the circuit's response capability to temperature changes, ensuring the accuracy of heating control and the stability of the system.

[0040] In addition, R2 is a current limiting resistor that plays a protective role in the circuit and does not change the voltage of the negative input terminal (V-).

[0041] Specifically, this embodiment uses comparator U1A to implement temperature control. Taking advantage of its fast switching characteristics, the output state is directly controlled based on the comparison result between the input signal and the set threshold. In this embodiment, the negative input terminal (V-) of the comparator is fixed at 2.5V through the voltage divider network formed by resistors R1 and R4, while the positive input terminal (V+) is adjusted through a voltage divider loop composed of resistors with different configurations and an NTC (negative temperature coefficient thermistor).

[0042] When variable resistor RP1 is set so that the positive input (V+) is pulled directly to ground (GND) through the NTC, V+ is 0V, which is lower than V- by 2.5V. Therefore, the comparator outputs a low level, field-effect transistor Q1 turns off, the PTC does not heat, and the system enters standby mode. RP1 is adjusted so that V+ is generated through the voltage divider circuit connecting the NTC and RP1. Its voltage is calculated as 5V * (R_NTC / (R_NTC + RP1 setting)). If the NTC resistance is greater than the RP1 setting, V+ will exceed 2.5V, the comparator outputs a high level, Q1 turns on, and the PTC begins heating. As the temperature rises, the NTC resistance decreases. When the resistance falls below the RP1 setting, V+ drops below 2.5V, the comparator outputs a low level, Q1 turns off, and the PTC stops heating. Subsequently, as the PTC stops heating, the temperature drops, and the NTC resistance increases again, repeating the process, achieving automatic temperature control.

[0043] Reference Figure 4 , the utility model provides another automatic heating temperature control circuit:

[0044] The voltage divider submodule 210 includes a first resistor R7, a second resistor R8, a third resistor R9, a fourth resistor R10, a fifth resistor R11, a sixth resistor R12, and a rotary switch SW1. The rotary switch SW1 includes a first contact, a second contact, a third contact, a fourth contact, a fifth contact, a sixth contact, a seventh contact, and a selection contact. One end of the selection contact is connected to the power supply end, and the other end is connected to any one of the first contact, the second contact, the third contact, the fourth contact, the fifth contact, the sixth contact, and the seventh contact. The first contact is floating. The second contact is connected in series with the first resistor R7 to the common end. The third contact is connected in series with the second resistor R8 to the common end. The fourth contact is connected in series with the third resistor R9 to the common end. The fifth contact is connected in series with the fourth resistor R10 to the common end. The sixth contact is connected in series with the fifth resistor R11 to the common end. The seventh contact is connected in series with the sixth resistor R12 to the common end.

[0045] This embodiment implements flexible temperature control by configuring a rotary switch SW1 and a plurality of series resistors (R7 to R12) in the voltage divider submodule 210: the rotary switch SW1 allows the user to select different resistance configurations, thereby adjusting the resistance connected to the common terminal. In this way, the user can precisely control the voltage signal generated by the voltage divider submodule, which is then used in the signal processing module to compare and determine the working state of the heating element. Through this design, this embodiment can adapt to different temperature control requirements and effectively adjust and maintain the required temperature level. Selecting different contacts and corresponding resistors allows the system to operate within a wider temperature range, thereby enhancing the applicability and flexibility of the system. This adjustability not only improves the efficiency of the heating process, but also ensures the uniformity and safety of heating, and is suitable for application scenarios requiring precise temperature management.

[0046] Specifically, when the knob switch SW1 is connected to pin 1, the positive input terminal (V+) is directly pulled to the ground (GND) through the NTC, causing V+ to be 0V, which is lower than V-'s 2.5V. Therefore, the comparator outputs a low level, the field effect transistor Q1 is not turned on, the PTC does not heat, and the system is in standby mode.

[0047] When SW1 is connected to pin 2, V+ is generated by the voltage divider circuit connecting the NTC and R7. Its voltage is calculated by 5V*(R_NTC / (R_NTC + 65K)). If the resistance of the NTC is greater than 65KΩ, V+ will be higher than 2.5V, the comparator outputs a high level, Q1 turns on, and the PTC starts heating. As the temperature rises, the resistance of the NTC decreases. When the resistance is lower than 65KΩ, V+ drops to below 2.5V, the comparator outputs a low level, Q1 turns off, and the PTC stops heating. Subsequently, as the PTC stops heating, the temperature drops, and the resistance of the NTC increases again. The process repeats, achieving automatic temperature control.

[0048] The above is only used to illustrate the technical solution of the present invention and is not intended to limit it. Other modifications or equivalent substitutions made to the technical solution of the present invention by ordinary technicians in this field should be included in the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solution of the present invention.

Claims

1. An automatic heating temperature control circuit, characterized in that: The invention comprises an input circuit (100), a voltage division control circuit (200), a signal processing module (300) and a working circuit (400), wherein the input circuit (100) is connected to a first input end of the signal processing module (300), the voltage division control circuit (200) is connected to a second input end of the signal processing module (300), and the working circuit (400) is connected to a first output end of the signal processing module (300). The signal processing module (300) is used to compare signals from the input circuit (100) and the voltage division control circuit (200) and output a control signal. The input circuit (100) is used to output a reference voltage signal, the voltage division control circuit (200) is used to output a comparison voltage signal, and the working circuit (400) is used to drive a load to operate according to the output signal of the signal processing module (300).

2. The automatic heating temperature control circuit according to claim 1, characterized in that: The voltage dividing control circuit (200) comprises a voltage dividing submodule (210) and a temperature sensing module (220); one end of the temperature sensing module (220) is grounded, and the other end is connected to one end of the voltage dividing submodule (210) to form a common end; the other end of the voltage dividing submodule (210) is connected to a power supply end; the second input end of the signal processing module (300) is connected to the common end; and the power supply end is grounded to the temperature sensing module (220) through the voltage dividing submodule (210) to form a loop.

3. The automatic heating temperature control circuit according to claim 2, characterized in that: The input voltage of the second input terminal of the signal processing module (300) is the divided voltage of the temperature sensing module (220) at the power supply terminal.

4. The automatic heating temperature control circuit according to claim 3, characterized in that: The temperature sensing module (220) comprises a temperature sensing resistor NTC1, one end of the temperature sensing resistor NTC1 is grounded, and the other end is connected to the voltage divider module (210).

5. An automatic heating temperature control circuit according to claim 2 or 3, characterized in that: The voltage divider module (210) includes a first resistor R7, a second resistor R8, a third resistor R9, a fourth resistor R10, a fifth resistor R11, a sixth resistor R12, and a rotary switch SW1. The rotary switch SW1 includes a first contact, a second contact, a third contact, a fourth contact, a fifth contact, a sixth contact, a seventh contact, and a selection contact. One end of the selection contact is connected to the power supply end, and the other end is connected to any one of the first contact, the second contact, the third contact, the fourth contact, the fifth contact, the sixth contact, and the seventh contact. The first contact is suspended. The second contact is connected in series with the first resistor R7 to the common end. The third contact is connected in series with the second resistor R8 to the common end. The fourth contact is connected in series with the third resistor R9 to the common end. The fifth contact is connected in series with the fourth resistor R10 to the common end. The sixth contact is connected in series with the fifth resistor R11 to the common end. The seventh contact is connected in series with the sixth resistor R12 to the common end.

6. An automatic heating temperature control circuit according to claim 2 or 3, characterized in that: The voltage divider module (210) comprises a variable resistor RP1, a sliding end of the variable resistor RP1 is connected to a power supply end, a first fixed end of the variable resistor RP1 is connected to the voltage divider module (210) and a second input end of the signal processing module (300), and a second fixed end of the variable resistor RP1 is suspended.

7. The automatic heating temperature control circuit according to claim 2, characterized in that: A seventh resistor R6 is further provided between the second input terminal of the signal processing module (300) and the common terminal.

8. The automatic heating temperature control circuit according to claim 1, characterized in that: The working circuit (400) comprises an eighth resistor R3, a ninth resistor R5, a switch tube Q1 and a heating interface CN1, one end of the eighth resistor R3 is connected to the first output end of the signal processing module (300), the other end of the eighth resistor R3 is connected to one end of the ninth resistor R5 and the gate of the switch tube Q1, the other end of the ninth resistor R5 is connected to the source and the ground end of the switch tube Q1, the drain of the switch tube Q1 is connected to the first port of the heating interface CN1, and the second port of the heating interface CN1 is connected to the power supply end.

9. The automatic heating temperature control circuit according to claim 1, characterized in that: The input circuit (100) comprises a tenth resistor R1, an eleventh resistor R2, and a twelfth resistor R4, one end of the tenth resistor R1 is connected to a power supply end, the other end of the tenth resistor R1 is connected to one end of the eleventh resistor R2 and one end of the twelfth resistor R4, the other end of the twelfth resistor R4 is grounded, and the other end of the eleventh resistor R2 is connected to the first input end of the signal processing module (300).

10. A heating device, characterized in that: The invention comprises an automatic heating temperature control circuit as described in any one of claims 1 to 9.

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