Water level detection circuit of full-automatic water feeding kettle and water feeding kettle applied to water level detection circuit

Abstract

The water level detection circuit comprises a connector J1, a second pin of the connector J1 is connected with a first water level and a second water level, a sixth capacitor C6 is connected between the second pin of the connector J1 and the second water level, a fifth pin and a sixth pin of the connector J1 are further connected with a first capacitor C1 and a second capacitor C2 respectively, and the first capacitor C1 and the second capacitor C2 are connected with the first capacitor C1 and the second capacitor C2 respectively. The first capacitor C1 is connected with a B end, and the second capacitor C2 is connected with an A end. The water level detection device has the advantages that electromagnetic interference is restrained through the resistance-capacitance filter network, and the stability and precision of water level detection are remarkably improved by combining a temperature compensation mechanism; and 2, modularized design is realized by adopting standardized elements, the production cost is reduced, the maintenance is convenient, and the structure is simple. And 3, water level and temperature signals are cooperatively processed, a detection result is dynamically calibrated, and misoperation caused by water quality or environment temperature change is avoided.

Description

Technical Field

[0001] This utility model relates to the field of water dispenser technology, specifically to a water level detection circuit for a fully automatic water dispenser and a water dispenser used in the circuit. Background Technology

[0002] Traditional water level detection devices in containers such as kettles often employ mechanical float switches or simple electrode sensors. Mechanical float switches trigger circuit switching by the rise and fall of a float. While simple in structure, they suffer from problems such as easy wear of mechanical parts, short lifespan, and low accuracy. They are particularly prone to failure due to scaling or corrosion, especially under high temperatures or in poor water quality conditions. Electrode sensors determine water level by detecting the conductivity of water, but are easily affected by changes in water quality (such as impurities and mineral content), leading to false detections. Furthermore, the electrodes are prone to oxidation from prolonged immersion, affecting reliability.

[0003] With the development of electronic technology, some water level detection circuits have adopted capacitive or resistive sensing technologies. However, existing electronic water level detection solutions often suffer from drawbacks such as complex circuit design, high cost, and insufficient anti-interference capabilities. For example, capacitive sensors are susceptible to changes in ambient temperature and electromagnetic interference, leading to unstable detection signals; resistive solutions require frequent calibration, resulting in high maintenance costs. Furthermore, the integration of existing water level detection circuits with the kettle control module is insufficient, resulting in signal transmission delays and making it difficult to achieve accurate real-time water level monitoring, leading to slow response or malfunctions in the automatic water filling function.

[0004] In practical applications of automatic water dispensers, achieving stable and high-precision water level detection while ensuring efficient coordination with the control module remains a pressing technical challenge. Existing technologies still fall short in balancing cost, interference resistance, and reliability, and most solutions do not adequately consider the impact of temperature changes on the detection circuit, further limiting their application scope.

[0005] Therefore, there is an urgent need for a water level detection circuit that is simple in structure, low in cost, and has strong anti-interference ability, as well as a fully automatic water filling kettle that integrates the circuit, in order to overcome the shortcomings of the existing technology and improve the accuracy of water level detection and the overall reliability of the system. Summary of the Invention

[0006] The present invention aims to at least solve one of the technical problems existing in the prior art. Therefore, one objective of the present invention is to provide a water level detection circuit for a fully automatic water dispenser that is simple in structure, has strong anti-interference capabilities, and integrates temperature compensation, as well as a water dispenser using this circuit.

[0007] This utility model also provides a water level detection circuit for a fully automatic kettle, including a connector J1. Pin 2 of the connector J1 is connected to a first water level and a second water level, and a sixth capacitor C6 is connected between pin 2 of the connector J1 and the second water level. Pins 5 and 6 of the connector J1 are also connected to a first capacitor C1 and a second capacitor C2, respectively. The first capacitor C1 is connected to terminal B, and the second capacitor C2 is connected to terminal A.

[0008] Furthermore, a fourth resistor R4 is also connected to the common terminal between pin 5 of connector J1 and the first capacitor C1.

[0009] Specifically, the fourth resistor R4 is connected in parallel with a third capacitor C3, and the other end of the third capacitor C3 is connected to the ground terminal GND.

[0010] Furthermore, the common terminal between pin 6 of connector J1 and the second capacitor C2 is also connected to a fourth capacitor C4, and the other end of the fourth capacitor C4 is connected to the ground terminal GND.

[0011] Furthermore, the fourth capacitor C4 is also connected in parallel with a third resistor R3.

[0012] Furthermore, pin 3 of connector J1 is also connected to one end of the second thermistor NTC2, and pin 4 of connector J1 is connected to the other end of the second thermistor NTC2.

[0013] Specifically, pin 7 of connector J1 is connected to a first resistor R1 and a second resistor R2 in sequence. The other end of the first resistor R1 is connected to the VCC terminal, and the other end of the second resistor R2 is connected to one end of the first thermistor NTC1. The common terminal of the second resistor R2 and the first thermistor NTC1 is connected to a fifth capacitor C5, and the other end of the fifth capacitor C5 is connected to pin 8 of connector J1.

[0014] Specifically, the connector J1 has an 8-pin ground terminal GND connected to it.

[0015] This utility model also discloses a water level detection circuit for a fully automatic water dispenser, characterized in that: it includes a kettle body and a water level detection circuit disposed inside the kettle body. The water level detection circuit is electrically connected to the control module MCU of the kettle body through connector J1, and is used to detect the water level in the kettle in real time and control the automatic water filling function.

[0016] The beneficial effects of this utility model are as follows.

[0017] I. Electromagnetic interference is suppressed through an RC filter network, combined with a temperature compensation mechanism, significantly improving the stability and accuracy of water level detection and achieving high reliability. II. Standardized components are used to achieve a modular design, reducing production costs and facilitating maintenance, resulting in a simple structure. III. Water level and temperature signals are processed collaboratively, and detection results are dynamically calibrated to avoid malfunctions caused by changes in water quality or ambient temperature. IV. Optimized signal transmission paths and control logic ensure rapid response of the automatic water filling function, improving user experience and providing a fast response advantage. Attached Figure Description

[0018] The above and / or additional aspects and advantages of this invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings.

[0019] Figure 1 This is the circuit diagram of this utility model. Detailed Implementation

[0020] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0021] The following is for reference. Figure 1 The present invention describes a fully automatic water level detection circuit for a kettle, comprising a connector J1, wherein pin 2 of the connector J1 is connected to a first water level and a second water level, and a sixth capacitor C6 is connected between pin 2 of the connector J1 and the second water level; pins 5 and 6 of the connector J1 are also connected to a first capacitor C1 and a second capacitor C2, respectively; the first capacitor C1 is connected to terminal B, and the second capacitor C2 is connected to terminal A.

[0022] In this circuit, the common terminal between pin 5 of connector J1 and the first capacitor C1 is also connected to a fourth resistor R4. The fourth resistor R4 is connected in parallel with a third capacitor C3, the other end of which is connected to ground GND. The common terminal between pin 6 of connector J1 and the second capacitor C2 is also connected to a fourth capacitor C4, the other end of which is connected to ground GND. The fourth capacitor C4 is also connected in parallel with a third resistor R3. Pin 3 of connector J1 is also connected to one end of a second thermistor NTC2, and pin 4 of connector J1 is connected to the other end of the second thermistor NTC2. Pin 7 of connector J1 is sequentially connected to a first resistor R1 and a second resistor R2. The other end of the first resistor R1 is connected to VCC, and the other end of the second resistor R2 is connected to one end of the first thermistor NTC1. The common terminal of the second resistor R2 and the first thermistor NTC1 is connected to a fifth capacitor C5, the other end of which is connected to pin 8 of connector J1. Pin 8 of connector J1 is connected to ground GND.

[0023] This utility model discloses a water level detection circuit for a fully automatic water dispenser, including a kettle body and a water level detection circuit disposed inside the kettle body. The water level detection circuit is electrically connected to the control module MCU of the kettle body through connector J1, and is used to detect the water level in the kettle in real time and control the automatic water filling function.

[0024] Example 1: The specific configuration of the water level detection circuit is as follows:

[0025] like Figure 1 As shown, this circuit includes connector J1, first capacitors C1 to C6, first resistors R1 to R4, first thermistor NTC1, and second thermistor NTC2, with the following connections:

[0026] I. Signal Output Terminal (Path A):

[0027] Connect the second capacitor C2 (with a capacitance of 0.1μF) to pin A in sequence from pin 6 of connector J1;

[0028] A parallel branch is provided between pin 6 of connector J1 and the second capacitor C2: the fourth capacitor C4 (capacitance is 0.01μF) is connected to the ground terminal GND, and the fourth capacitor C4 is connected in parallel with the third resistor R3 (resistance is 10kΩ), forming an RC low-pass filter network to suppress high-frequency interference.

[0029] II. Signal Detection Terminal (B-end Path):

[0030] Connect the first capacitor C1 (with a capacitance of 0.1μF) to terminal B in sequence from pin 5 of connector J1;

[0031] A parallel branch is provided between pin 5 of connector J1 and the first capacitor C1: the fourth resistor R4 (resistance value is 10kΩ) to the third capacitor C3 (capacitance value is 0.01μF) to the ground terminal GND, forming a secondary filter.

[0032] III. Water level probe interface:

[0033] Pin 2 of connector J1 is connected to both the first and second water level probes, which are located at different heights inside the kettle.

[0034] The electrical signal is amplified through the sixth capacitor C6 (with a capacitance of 0.1μF) at pin 2 of connector J1.

[0035] IV. Temperature Compensation Module:

[0036] The first thermistor NTC1 (MF58 type): One end of the first thermistor NTC1 is connected to pin 7 of connector J1, and the other end is connected in sequence to the second resistor R2 (resistance value of 2kΩ), the first resistor R1 (resistance value of 5kΩ) and the VCC terminal (voltage of 5V).

[0037] Common node compensation: the connection point between the second resistor R2 and NTC1, the fifth capacitor C5 (0.1μF), and pin 8 of connector J1 and ground terminal GND;

[0038] The second thermistor, NTC2, is connected to pins 3 and 4 of J1 respectively, and is used to assist in monitoring the internal temperature of the kettle.

[0039] Example 2: The integrated application of the kettle is as follows.

[0040] High-frequency detection signal path:

[0041] The control module MCU is coupled to terminal A via the second capacitor C2, and outputs a 100kHz square wave along terminal A to the metal layer D1 of the pot body.

[0042] Water level detection mechanism: When the water level covers the probe (first water level / second water level), the high-frequency signal from the kettle body D1 passes sequentially through the water medium inside the kettle, the sixth capacitor C6, and pin 2 of connector J1, and is finally fed back to the control module MCU.

[0043] The signal from the kettle body is bypassed to ground and detected as attenuating at terminal B (voltage amplitude drop ≥50%). The control module MCU determines the water level status based on the signal attenuation amplitude at terminal B.

[0044] Temperature compensation process: The control module MCU acquires the voltage division value of the first thermistor NTC1 (formula: V_NTC = VCC × RNTC / (R1 + R2 + RNTC)), where VCC is in volts (V), and R1, R2, and RNTC are in ohms (Ω). This dynamically calibrates the water level trigger threshold (for example, when the water temperature is 60℃, the threshold is lowered by 20% to compensate for changes in water conductivity).

[0045] Anti-interference design: The first capacitor C1 to the fourth capacitor C4 form a four-stage filter network to suppress electromagnetic noise below 200kHz generated by motors, etc. The signal transmission line uses shielded twisted pair cable (the distance from connector J1 to the control module MCU is ≤10cm).

[0046] Example 3: Key component parameters are optimized as follows:

[0047] The parameters of the first capacitor C1 and the second capacitor C2 are 0.1μF ceramic capacitors (X7R), and their function is signal coupling and high-frequency filtering;

[0048] The third capacitor C3 and the fourth capacitor C4 are 0.01μF ceramic capacitors (NP0), and their function is to suppress low-frequency interference.

[0049] The sixth capacitor, C6, is a 0.1μF / 25V electrolytic capacitor, and its function is to amplify the water level signal.

[0050] The parameters of the third resistor R3 and the fourth resistor R4 are 10kΩ metal film resistors (±1%), and their function is to match the impedance of the filter network.

[0051] The first thermistor, NTC1, is an MF58 type (B value = 3950K), with a temperature detection range of -20℃ to 120℃.

[0052] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A water level detection circuit for a fully automatic kettle, comprising a connector J1, characterized in that: The connector J1 has pin 2 connected to the first water level and the second water level, and a sixth capacitor C6 is connected between pin 2 of the connector J1 and the second water level. Pins 5 and 6 of the connector J1 are also connected to the first capacitor C1 and the second capacitor C2, respectively. The first capacitor C1 is connected to terminal B, and the second capacitor C2 is connected to terminal A.

2. The water level detection circuit for the fully automatic kettle according to claim 1, characterized in that: A fourth resistor R4 is also connected to the common terminal between pin 5 of connector J1 and the first capacitor C1.

3. The water level detection circuit for the fully automatic kettle according to claim 2, characterized in that: The fourth resistor R4 is connected in parallel with the third capacitor C3, and the other end of the third capacitor C3 is connected to the ground terminal GND.

4. The water level detection circuit for the fully automatic kettle according to claim 1, characterized in that: The common terminal between pin 6 of connector J1 and the second capacitor C2 is also connected to a fourth capacitor C4, and the other end of the fourth capacitor C4 is connected to the ground terminal GND.

5. The water level detection circuit for the fully automatic kettle according to claim 4, characterized in that: The fourth capacitor C4 is also connected in parallel with a third resistor R3.

6. The water level detection circuit for the fully automatic kettle according to claim 1, characterized in that: Pin 3 of connector J1 is also connected to one end of the second thermistor NTC2, and pin 4 of connector J1 is connected to the other end of the second thermistor NTC2.

7. The water level detection circuit for the fully automatic kettle according to claim 1, characterized in that: The connector J1 has a first resistor R1 and a second resistor R2 connected to pin 7 in sequence. The other end of the first resistor R1 is connected to the VCC terminal. The other end of the second resistor R2 is connected to one end of the first thermistor NTC1. The common terminal of the second resistor R2 and the first thermistor NTC1 is connected to a fifth capacitor C5. The other end of the fifth capacitor C5 is connected to pin 8 of the connector J1.

8. The water level detection circuit for the fully automatic kettle according to claim 7, characterized in that: The connector J1 has an 8-pin ground terminal GND connected to it.

9. A water level detection circuit for an automatic water dispenser according to any one of claims 1 to 8, characterized in that: It includes a kettle body and a water level detection circuit installed inside the kettle body. The water level detection circuit is electrically connected to the control module MCU of the kettle body through connector J1, and is used to detect the water level in the kettle in real time and control the automatic water filling function.

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