Liquid temperature reuse detection device, electric kettle and control circuit

Abstract

This application relates to a liquid temperature multiplexing detection device, an electric kettle, and a control circuit. The liquid temperature multiplexing detection device includes a five-ring connector, a temperature detection device, a single-ended electrode, a first switch, a second switch, a signal processing module, and a control unit. The temperature detection device is disposed inside the kettle. The first electrode of the temperature detection device is electrically connected to the third ring of the five-ring connector and the first switch. The second electrode of the temperature detection device is electrically connected to the fifth ring of the five-ring connector, the second switch, and the single-ended electrode disposed inside the kettle. The control unit controls the first and second switches. The second switch is also electrically connected to the signal processing module, which is coupled and electrically connected to the control unit. This application solves the problem in related technologies where electric kettles use six-ring connectors for composite liquid temperature detection, requiring improvements to the kettle layout design and resulting in poor composite liquid temperature detection performance.

Description

Technical Field

[0001] This application relates to the field of electric kettle technology, and in particular to a liquid temperature reuse detection device, an electric kettle, and a control circuit. Background Technology

[0002] Electric kettles and other small household appliances have become frequently used devices in people's daily lives. Currently, the liquid level detection and water temperature detection of electric kettles are combined on the kettle's connector. For example, the liquid level detection sensor is connected to the corresponding ring of a five-ring connector, and the temperature detection sensor is connected to one ring of a five-ring connector. In related technologies, when liquid level detection and water temperature detection are combined, a six-ring connector is required for the corresponding connection. However, this is not suitable for electric kettles that currently use five-ring connectors. It is necessary to change the relevant mold and circuit design and replace the five-ring connector with a six-ring connector to meet the combined liquid and temperature detection requirements. However, changing the design of the electric kettle's five-ring connector to a six-ring connector increases the mold design and development cost. Secondly, using a six-ring connector requires adaptation adjustments to the current control circuit and component installation, increasing the electric kettle's processing cost. Moreover, the combined liquid and temperature detection effect is poor, which can easily cause the electric kettle's liquid level detection and temperature detection control to fail.

[0003] Currently, no effective solution has been proposed for the problem that electric kettles using six-ring connectors for composite liquid temperature detection require improvements to the kettle layout design and that the composite liquid temperature detection effect is not good. Utility Model Content

[0004] In view of this, it is necessary to provide a liquid temperature reuse detection device, an electric kettle, and a control circuit to at least solve the problem in the related technology that the electric kettle uses a six-ring connector for composite liquid temperature detection, which requires improvement of the electric kettle layout design and results in poor liquid temperature composite detection effect.

[0005] In a first aspect, this application provides a technical solution as follows: a liquid temperature multiplexing detection device for an electric kettle, comprising a five-ring connector, a temperature detection device, a single-ended electrode, a first switching switch, a second switching switch, a signal processing module, and a control unit. The temperature detection device is disposed within the kettle body, and the first electrode of the temperature detection device is electrically connected to the third ring of the five-ring connector and the first switching switch, respectively. The second electrode of the temperature detection device is electrically connected to the fifth ring of the five-ring connector, the second switching switch, and the single-ended electrode disposed within the kettle body. The control unit controls and electrically connects the first switching switch and the second switching switch. The second switching switch is also electrically connected to the signal processing module, which is coupled and electrically connected to the control unit. When a temperature detection control signal is received from the control unit, the first switching switch is used to... The first electrode is connected to the control unit, and the second switch is used to connect the second electrode to ground. When a liquid level detection signal is received from the control unit, the first switch is used to disconnect the first electrode from the control unit, and the second switch is used to connect the single-ended electrode to the signal processing module. When the first electrode is connected to the control unit and the second electrode is connected to ground, the temperature detection device is used to detect the water temperature inside the kettle, so that the control unit can control the electric kettle to perform the corresponding boiling operation according to the water temperature. When the first electrode is disconnected from the control unit and the single-ended electrode is connected to the signal processing module, the signal processing module detects the liquid level inside the kettle through the single-ended electrode, so that the control unit can control the electric kettle to perform the corresponding water filling operation according to the liquid level.

[0006] In one embodiment, both the first and second switching switches include analog switches. Each analog switch includes a controlled terminal, a common input terminal, a normally open output terminal, a normally closed output terminal, a power supply terminal, and a ground terminal. The controlled terminal is electrically connected to the liquid level multiplexing control port of the control unit. The power supply terminal is electrically connected to a first power supply. The ground terminal is grounded. The common input terminal of the first switching switch is electrically connected to the first electrode and the third ring. The common input terminal of the second switching switch is electrically connected to the single-ended electrode and the fifth ring. The normally open output terminal of the first switching switch is electrically connected to the temperature detection port of the control unit through a sampling unit. The normally open output terminal of the second switching switch is grounded. The normally closed output terminal of the first switching switch is left floating. The normally closed output terminal of the second switching switch is connected to one detection electrode port of the signal processing module.

[0007] The analog switch is used to control the common input terminal to connect with the normally open output terminal when the controlled terminal receives the temperature detection control signal, and to control the common input terminal to connect with the normally closed output terminal when the controlled terminal receives the liquid level detection signal.

[0008] When the common input terminal is connected to the normally open output terminal, the first switch connects the first electrode to the control unit, and the second switch connects the second electrode to ground; when the common input terminal is connected to the normally closed output terminal, the first switch disconnects the first electrode from the control unit, and the second switch connects the single-ended electrode to the signal processing module.

[0009] In one embodiment, the analog switch includes an RS2057 model analog switch.

[0010] In one embodiment, the sampling unit includes a first resistor, a second resistor, a third resistor, and a first capacitor. One end of the first resistor is electrically connected to the first power supply, and the other end is electrically connected to one end of the second resistor, one end of the third resistor, and the normally open output terminal of the analog switch corresponding to the first switching switch. The other end of the second resistor is connected to the first capacitor and grounded. The other end of the third resistor is electrically connected to the temperature detection port of the control unit and the first capacitor.

[0011] The sampling unit is used to sample the level of the temperature signal output from the normally open output terminal of the analog switch corresponding to the first switching switch;

[0012] The control unit is used to detect the water temperature inside the kettle based on the level of the sampling unit.

[0013] In one embodiment, the temperature detection device includes an NTC temperature sensor.

[0014] In one embodiment, the single-ended electrode includes a capacitive liquid level sensor.

[0015] In one embodiment, the signal processing module includes an MC1081 digital capacitance sensor chip. One detection electrode port of the MC1081 digital capacitance sensor chip is electrically connected to the single-ended electrode and an ESD protection diode, respectively. The end of the ESD protection diode away from the one detection electrode port is grounded. The I²C interface of the MC1081 digital capacitance sensor chip is coupled and electrically connected to the control unit through an I²C serial communication bus. The MC1081 digital capacitance sensor chip is used to generate a corresponding liquid level value based on the capacitance value generated by the change in liquid level in the vessel body sensed by the single-ended electrode.

[0016] In one embodiment, the control unit includes one of the following: a microcontroller (MCU), a digital signal processor (DSP), or a programmable logic device (FPGA).

[0017] Secondly, this application provides a technical solution as follows: a control circuit for an electric kettle, including a liquid level reuse detection device electrically connected to a five-ring connector, wherein the liquid level reuse detection device includes the liquid temperature reuse detection device described in the first aspect.

[0018] Thirdly, embodiments of this application also provide an electric kettle, including a control circuit for controlling the operation of the electric kettle, wherein the control circuit is the control circuit for the electric kettle described in the second aspect.

[0019] Compared with related technologies, this embodiment provides a liquid temperature reuse detection device, an electric kettle, and a control circuit, including a five-ring connector, a temperature detection device, a single-ended electrode, a first switch, a second switch, a signal processing module, and a control unit. The temperature detection device is disposed inside the kettle, and its first electrode is electrically connected to the third ring of the five-ring connector and the first switch. The second electrode of the temperature detection device is electrically connected to the fifth ring of the five-ring connector, the second switch, and the single-ended electrode disposed inside the kettle. The control unit controls and electrically connects the first switch and the second switch. The second switch is also electrically connected to the signal processing module, which is coupled to and electrically connected to the control unit. When a temperature detection control signal is received from the control unit, the first electrode is connected to the control unit via the first switch, and the second electrode is connected to ground via the second switch. When a liquid level detection signal is received from the control unit, the first electrode is connected to the control unit via the first switch. The unit is disconnected and the single-ended electrode is connected to the signal processing module via the second switching switch; when the first electrode is connected to the control unit and the second electrode is connected to ground, the water temperature in the kettle is detected by the temperature detection device, so that the control unit can control the kettle to perform the corresponding boiling operation according to the water temperature; and when the first electrode is disconnected from the control unit and the single-ended electrode is connected to the signal processing module, the liquid level in the kettle is detected by the signal processing module through the single-ended electrode, so that the control unit can control the kettle to perform the corresponding water filling operation according to the liquid level. This solves the problem in related technologies where electric kettles use a six-ring connector for composite liquid temperature detection, which requires improvement of the electric kettle layout design and has poor composite liquid temperature detection effect. By reusing the connection of the temperature detection device and the liquid level detection device on the five-ring connector and switching them by the first switching switch and the second switching switch, the liquid level detection and temperature detection requirements are met without replacing the five-ring connector of the electric kettle, thereby enhancing the functionality of the electric kettle and reducing the processing cost of the electric kettle.

[0020] Details of one or more embodiments of this application are set forth in the following drawings and description to make other features, objects and advantages of this application more readily apparent. Attached Figure Description

[0021] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the present invention and, together with the description, serve to explain the principles of the present invention.

[0022] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 A structural block diagram of a liquid temperature reuse detection device provided in an embodiment of this application;

[0024] Figure 2 A topology diagram is provided for a preferred embodiment of this application. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0026] The electric kettle and control circuit of this application will be described below with reference to the accompanying drawings in the embodiments of this application and through specific embodiments.

[0027] Figure 1 A structural block diagram of a liquid temperature reuse detection device provided in an embodiment of this application; Figure 2 This is a topology diagram provided for a preferred embodiment of the present application. The liquid level reuse detection device shown in the diagram is applied to an electric kettle, enabling liquid level detection and temperature detection without replacing the five-ring connector of the electric kettle, thereby enhancing the functionality of the electric kettle and reducing its manufacturing cost.

[0028] Please see Figures 1 to 2 The liquid temperature multiplexing detection device of this application embodiment includes a five-ring connector 100, a temperature detection device 200, a single-ended electrode 300, a first switching switch 400, a second switching switch 500, a signal processing module 600, and a control unit 700. The temperature detection device 200 is disposed inside the kettle, and the first electrode of the temperature detection device 200 is electrically connected to the third ring of the five-ring connector 100 and the first switching switch 400, respectively. The second electrode of the temperature detection device 200 is electrically connected to the fifth ring of the five-ring connector 100, the second switching switch 500, and the single-ended electrode 300 disposed inside the kettle. The control unit 700 controls the first switching switch 400 and the second switching switch 500, and the second switching switch 500 is also electrically connected to the signal processing module 600, which is coupled and electrically connected to the control unit 700.

[0029] In this embodiment, the control unit 700 can be a microcontroller (MCU), a digital signal processor (DSP), or a programmable logic device (FPGA). In some optional embodiments, the control unit 700 is preferably an MCU of one of the following: R7F0C908B2 microprocessor, STC15F204 microcontroller, AT89S52 microcontroller, or EN8F677E microprocessor.

[0030] In this embodiment, when the liquid level in the kettle has not reached the preset water level (the preset water level represents the amount of water that needs to be added in the corresponding working mode, such as the initial water addition setting), the control unit 700 sends a liquid level detection signal to the first switch 400 and the second switch 500 (at this time, the level corresponding to the liquid level detection signal is low, for example, 0). The first switch 400 and the second switch 500 switch synchronously switch to disconnect the first electrode of the temperature detection device 200 from the control unit 700 and connect the single-ended electrode 300 to the signal processing module 600, thereby switching to the water level detection state. When the liquid level in the kettle reaches the preset water level, the control unit 700 sends a temperature detection signal to the first switch 400 and the second switch 500 (at this time, the level corresponding to the temperature detection signal is high, for example, 1). The first switch 400 and the second switch 500 switch synchronously switch to connect the first electrode of the temperature detection device 200 to the control unit 700 and connect the second electrode to ground, thereby switching to the temperature detection state.

[0031] In this embodiment, when a temperature detection control signal is received from the control unit 700, the first switching switch 400 is used to connect the first electrode to the control unit 700, and the second switching switch 500 is used to connect the second electrode to ground. When a liquid level detection signal is received from the control unit 700, the first switching switch 400 is used to disconnect the first electrode from the control unit 700, and the second switching switch 500 is used to connect the single-ended electrode 300 to the signal processing module 600.

[0032] In this embodiment, when the first electrode is connected to the control unit 700 and the second electrode is connected to ground, the temperature detection device 200 is used to detect the water temperature inside the kettle so that the control unit 700 can control the electric kettle to perform the corresponding boiling operation according to the water temperature.

[0033] In this embodiment, the temperature detection device 200 includes, but is not limited to, an NTC temperature sensor.

[0034] In this embodiment, when the first electrode is disconnected from the control unit 700 and the single-ended electrode 300 is connected to the signal processing module 600, the signal processing module 600 detects the liquid level in the kettle through the single-ended electrode 300, so that the control unit 700 can control the electric kettle to perform the corresponding water filling operation according to the liquid level.

[0035] In this embodiment, the single-ended electrode 300 includes, but is not limited to, a capacitive liquid level sensor. In this embodiment, the single-ended electrode 300 is used to generate a corresponding capacitance value based on the liquid volume injected into the vessel, and transmits the capacitance value to the signal processing module 600 through an electrical connection line. In this embodiment, the single-ended electrode 300 is also covered with an insulating protective layer for electrically isolating and protecting the single-ended electrode 300, thereby preventing corrosion and short circuits of the single-ended electrode 300.

[0036] In this embodiment, the signal processing module 600 is used to generate a water level value corresponding to the liquid capacity based on the received capacitance value, and transmit the water level value to the control unit 700 so that the control unit 700 controls the electric kettle to perform the corresponding water filling operation.

[0037] In some of these alternative implementations, refer to Figure 2 The signal processing module 600 includes an MC1081 digital capacitance sensor chip IC3, and one detection electrode port of the MC1081 digital capacitance sensor chip IC3 (reference). Figure 2 Pin C5 of IC3 is electrically connected to the single-ended electrode 300 and the ESD protection diode DR1, respectively. The end of the ESD protection diode DR1 furthest from the detection electrode port is grounded. The I²C interface of the MC1081 digital capacitance sensor chip IC3 (see reference) Figure 2 The SDA and SCL pins of IC3 communicate via the I²C serial bus (see reference). Figure 2 The network labels SDA and SCL are electrically coupled to the control unit 700. The MC1081 digital capacitance sensor chip IC3 is used to generate a corresponding liquid level value based on the capacitance value generated by the liquid level change in the pot sensed by the single-ended electrode 300.

[0038] In this embodiment, the MC1081 digital capacitive sensing chip IC3, together with the surrounding resistors and capacitors and the single-ended electrode 300 (as an external capacitor Csensor), constitutes a capacitive sensor. When measuring the water level, different water volumes will generate different oscillation signals. After frequency division by the MC1081 digital capacitive sensing chip IC3, the signal is sent to the digital logic circuit to measure and digitize the oscillation signal frequency. The digital logic uses a reference frequency to measure the oscillation signal frequency. Using the reference capacitor inside the MC1081 digital capacitive sensing chip IC3, the capacitance corresponding to the oscillation signal frequency is calculated from the DATA value in the register through a calculation formula. The change in capacitance is obtained, and the control unit 700 determines the current water level in the kettle in real time based on the change in capacitance and a preset capacitance water level parameter table.

[0039] Understandably, the MC1081 digital capacitive sensing chip IC3 operates by connecting to a single-ended electrode 300 to measure the water level inside the kettle. In one optional embodiment, the MC1081 digital capacitive sensing chip IC3 is connected to multiple single-ended electrodes 300 to measure the current water level inside the kettle and perform linear regression on the current water level to determine the real-time water level inside the kettle, thereby providing accuracy in detecting the water level inside the kettle and achieving precise control of water filling in the electric kettle.

[0040] In the above-mentioned liquid temperature reuse detection device, the temperature detection device 200 and the liquid level detection device (corresponding to the single-ended electrode 300) are reused on the five-ring connector 100, and the switching is performed by the first switching switch 400 and the second switching switch 500. This allows the liquid level detection and temperature detection requirements to be met without replacing the five-ring connector 100 of the electric kettle, thereby enhancing the functionality of the electric kettle and reducing the processing cost of the electric kettle.

[0041] To achieve liquid temperature reuse switching, refer to Figure 1 and Figure 2 In some embodiments, both the first switching switch 400 and the second switching switch 500 include analog switches (see reference). Figure 2 IC1 and IC2 in the analog switch (refer to IC1 and IC2), the analog switch includes the controlled terminal (reference) Figure 2 IN ports of IC1 and IC2), common input (refer to) Figure 2 COM ports of IC1 and IC2), normally open outputs (refer to...) Figure 2 The NO ports of IC1 and IC2), normally closed output terminals (refer to...) Figure 2 NC ports of IC1 and IC2), power supply (reference) Figure 2 V+ ports of IC1 and IC2 and ground (refer to) Figure 2 The GND ports of IC1 and IC2, and the level multiplexing control port of the controlled terminal and control unit 700 (see reference). Figure 2The MCU's I / O ports are electrically connected, the power supply is electrically connected to the first power supply (corresponding to +5V), and the ground is connected to ground. The first switching switch is 400 (reference). Figure 2 The common input terminal of IC2 is electrically connected to the first electrode and the third ring, and the second switching switch 500 (reference) Figure 2 The common input terminal of IC1 is electrically connected to the single-ended electrode 300 and the fifth ring. The normally open output terminal of the first switching switch 400 is connected to the temperature detection port of the control unit 700 (reference) through the sampling unit. Figure 2 The ADC port of the MCU is electrically connected. The normally open output of the second switch 500 is grounded, and the normally closed output of the first switch 400 is left floating high. The normally closed output of the second switch 500 is connected to one detection electrode port of the signal processing module 600.

[0042] An analog switch is used to connect the common input terminal to the normally open output terminal when a temperature detection control signal is received at the controlled end, and to connect the common input terminal to the normally closed output terminal when a liquid level detection signal is received at the controlled end.

[0043] In this embodiment, the analog switch includes, but is not limited to, the RS2057 analog switch;

[0044] When the common input terminal is connected to the normally open output terminal, the first switch 400 connects the first electrode to the control unit 700, and the second switch 500 connects the second electrode to ground; when the common input terminal is connected to the normally closed output terminal, the first switch 400 disconnects the first electrode from the control unit 700, and the second switch 500 connects the single-ended electrode 300 to the signal processing module 600.

[0045] In some of these alternative implementations, refer to Figure 2 The sampling unit includes a first resistor R66, a second resistor R64, a third resistor R65, and a first capacitor C13. One end of the first resistor R66 is electrically connected to the first power supply (corresponding to +5V power supply), and the other end is electrically connected to one end of the second resistor R64, one end of the third resistor R65, and the normally open output terminal of the analog switch corresponding to the first switching switch 400. The other end of the second resistor R64 is connected to the first capacitor C13 and grounded. The other end of the third resistor R65 is electrically connected to the temperature detection port of the control unit 700 and the first capacitor C13.

[0046] The sampling unit is used to sample the level of the temperature signal output from the normally open output terminal of the analog switch corresponding to the first switching switch 400;

[0047] The control unit is used to detect the water temperature inside the kettle based on the level of the sampling unit.

[0048] This application also provides a control circuit for an electric kettle, including a liquid level reuse detection device electrically connected to a five-ring connector, which is the liquid level reuse detection device in the above embodiments.

[0049] This application also provides an electric kettle, including a control circuit for controlling the operation of the electric kettle, which is the control circuit of the electric kettle in the above embodiment.

[0050] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive elements that are not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0051] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A liquid temperature reuse detection device for an electric kettle, characterized in that, The device includes a five-ring connector, a temperature detection device, a single-ended electrode, a first switch, a second switch, a signal processing module, and a control unit. The temperature detection device is disposed inside the kettle body, and its first electrode is electrically connected to the third ring of the five-ring connector and the first switch. The second electrode of the temperature detection device is electrically connected to the fifth ring of the five-ring connector, the second switch, and the single-ended electrode disposed inside the kettle body. The control unit controls and electrically connects the first switch and the second switch. The second switch is also electrically connected to the signal processing module, which is coupled and electrically connected to the control unit. When a temperature detection control signal is received from the control unit, the first switch is used to connect the first electrode to the control unit, and the second switch is used to connect the second electrode to ground. When a liquid level detection signal is received from the control unit, the first switch is used to disconnect the first electrode from the control unit, and the second switch is used to connect the single-ended electrode to the signal processing module. When the first electrode is connected to the control unit and the second electrode is connected to ground, the temperature detection device is used to detect the water temperature inside the kettle so that the control unit can control the electric kettle to perform the corresponding boiling water operation according to the water temperature. When the first electrode is disconnected from the control unit and the single-ended electrode is connected to the signal processing module, the signal processing module detects the liquid level inside the kettle through the single-ended electrode, so that the control unit can control the electric kettle to perform the corresponding water filling operation according to the liquid level.

2. The liquid temperature reuse detection device according to claim 1, characterized in that, Both the first and second switching switches include analog switches. Each analog switch includes a controlled terminal, a common input terminal, a normally open output terminal, a normally closed output terminal, a power supply terminal, and a ground terminal. The controlled terminal is electrically connected to the liquid level multiplexing control port of the control unit. The power supply terminal is electrically connected to a first power supply. The ground terminal is grounded. The common input terminal of the first switching switch is electrically connected to the first electrode and the third ring. The common input terminal of the second switching switch is electrically connected to the single-ended electrode and the fifth ring. The normally open output terminal of the first switching switch is electrically connected to the temperature detection port of the control unit through a sampling unit. The normally open output terminal of the second switching switch is grounded. The normally closed output terminal of the first switching switch is left floating. The normally closed output terminal of the second switching switch is connected to one detection electrode port of the signal processing module. The analog switch is used to control the common input terminal to connect with the normally open output terminal when the controlled terminal receives the temperature detection control signal, and to control the common input terminal to connect with the normally closed output terminal when the controlled terminal receives the liquid level detection signal. When the common input terminal is connected to the normally open output terminal, the first switch connects the first electrode to the control unit, and the second switch connects the second electrode to ground; when the common input terminal is connected to the normally closed output terminal, the first switch disconnects the first electrode from the control unit, and the second switch connects the single-ended electrode to the signal processing module.

3. The liquid temperature reuse detection device according to claim 2, characterized in that, The analog switch includes the RS2057 model analog switch.

4. The liquid temperature reuse detection device according to claim 2, characterized in that, The sampling unit includes a first resistor, a second resistor, a third resistor, and a first capacitor. One end of the first resistor is electrically connected to the first power supply, and the other end is electrically connected to one end of the second resistor, one end of the third resistor, and the normally open output terminal of the analog switch corresponding to the first switching switch. The other end of the second resistor is connected to the first capacitor and grounded. The other end of the third resistor is electrically connected to the temperature detection port of the control unit and the first capacitor. The sampling unit is used to sample the level of the temperature signal output from the normally open output terminal of the analog switch corresponding to the first switching switch; The control unit is used to detect the water temperature inside the kettle based on the level of the sampling unit.

5. The liquid temperature reuse detection device according to claim 2, characterized in that, The temperature detection device includes an NTC temperature sensor.

6. The liquid temperature reuse detection device according to claim 2, characterized in that, The single-ended electrode includes a capacitive liquid level sensor.

7. The liquid temperature reuse detection device according to claim 2, characterized in that, The signal processing module includes an MC1081 digital capacitive sensing chip. One detection electrode port of the MC1081 digital capacitive sensing chip is electrically connected to the single-ended electrode and the ESD protection diode. The end of the ESD protection diode away from the detection electrode port is grounded. The I²C interface of the MC1081 digital capacitive sensing chip is coupled and electrically connected to the control unit through an I²C serial communication bus. The MC1081 digital capacitive sensing chip is used to generate a corresponding liquid level value based on the capacitance value generated by the liquid level change in the vessel body sensed by the single-ended electrode.

8. The liquid temperature reuse detection device according to any one of claims 1 to 7, characterized in that, The control unit includes one of the following: a microcontroller (MCU), a digital signal processor (DSP), or a programmable logic device (FPGA).

9. A control circuit for an electric kettle, comprising a liquid level multiplexing detection device electrically connected to a five-ring connector, characterized in that, The liquid level reuse detection device includes the liquid temperature reuse detection device according to any one of claims 1 to 8.

10. An electric kettle, characterized in that, The device includes a control circuit for controlling the operation of the electric kettle, the control circuit being the same as the control circuit for the electric kettle as described in claim 9.

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