Flameout protection device of gas cooker and gas cooker

Abstract

The utility model discloses a flameout protection device for a gas cooker, which relates to the technical field of flameout protection circuits and comprises a control chip, a flame detection circuit, an electromagnetic valve detection circuit, a relay and an electromagnetic valve. The control chip receives a flame state signal, detected by the flame detection circuit, of the gas cooker and an electromagnetic valve working state signal, detected by the electromagnetic valve circuit, of the electromagnetic valve, and judges whether the flame state signal or the electromagnetic valve working state signal is in a fault state or not. And according to the judgment result, the relay is controlled to carry out on-off control on the electromagnetic valve. Potential safety hazards caused by failure of a driving circuit are avoided by adopting double-path detection and double driving, gas valve control is independently controlled by two chips capable of independently detecting flame signals, and output contacts of two paths of relays respectively controlled by a main chip and an auxiliary chip are connected in series, so that a gas control part is prevented from being out of control.

Description

Technical Field

[0001] This utility model relates to the field of flameout protection circuit technology, specifically to a flameout protection device for gas stoves. Background Technology

[0002] Currently, commercial gas flameout protection devices, as a core technology for ensuring the safety of gas equipment, mainly use ion probes to detect the presence of flames and then link them with solenoid valves to control the gas supply. Their core principle is based on the ionization characteristics of flames: when a flame burns, the high temperature ionizes the surrounding gas, forming a conductive path. A weak current of approximately 0.1–5 μA is generated between the probe and the burner. This signal, after being processed by an amplification circuit, keeps the solenoid valve open. Once the flame is accidentally extinguished, the current disappears, and the system will cut off the gas supply within 0.1 seconds.

[0003] However, this technology still faces multiple safety hazards in practical applications. For example, at the detection end, ion probes are susceptible to environmental interference, leading to misjudgments. For instance, oil stains and carbon deposits adhering to the probe surface can create false conductive paths, potentially detecting residual current even after the flame is extinguished, causing the system to misjudge it as continued combustion. In high humidity or strong electromagnetic field environments, stray currents generated by air ionization can also trigger erroneous signals. Furthermore, poor contact between the probe and the burner (such as oxidation or loosening) significantly reduces the effective signal strength, leading to the risk of missed detections. Prolonged high-temperature operation accelerates probe aging, and decreased sensitivity may delay protection actions; some probes show significantly longer response times after two years of continuous use. Additionally, the main safety hazards at the actuator end are concentrated in the solenoid valve drive. When the control relay contacts stick or the drive circuit fails, the gas valve may remain open even after the detection system has issued a valve-closing command. This phenomenon is particularly prominent in the high-temperature, high-humidity environment of commercial kitchens—the probability of increased contact resistance due to relay contact oxidation is much higher than in residential environments. A more insidious risk stems from circuit design flaws: if a current monitoring module is not included in the drive circuit, the solenoid valve may fail to close due to continuous power supply when the transistor breaks down or the filter capacitor leaks. Accident analysis reports from some commercial stove brands indicate that a significant proportion of safety incidents originate from drive circuit failure rather than probe malfunction.

[0004] There are currently no effective solutions to the problems in the relevant technologies. Utility Model Content

[0005] In view of the problems in the related technologies, this utility model proposes a flameout protection device for gas stoves to overcome the above-mentioned technical problems existing in the existing related technologies.

[0006] Therefore, the specific technical solution adopted by this utility model is as follows:

[0007] A flameout protection device for a gas stove, comprising:

[0008] Control chip, flame detection circuit, solenoid valve detection circuit, relay and solenoid valve;

[0009] The input terminals of the control chip are connected to the flame detection circuit and the solenoid valve detection circuit respectively, the output terminal of the control chip is connected to the relay input terminal, and the relay output terminal is connected to one end of the solenoid valve.

[0010] The control chip receives the flame status signal of the gas stove detected by the flame detection circuit and the solenoid valve working status signal of the solenoid valve detected by the solenoid valve circuit. It determines whether the flame status signal or the solenoid valve working status signal is in a fault state, and controls the relay to control the solenoid valve to open or close the circuit based on the determination result.

[0011] Furthermore, when either the flame status signal or the solenoid valve operating status signal is a fault status signal, the control chip controls the relay to disconnect the circuit of the solenoid valve.

[0012] Furthermore, the control chip includes a main chip and an auxiliary chip; both the main chip and the auxiliary chip independently control the relay to disconnect the circuit of the solenoid valve.

[0013] Furthermore, the flame detection circuit includes a main flame detection circuit and an auxiliary flame detection circuit; the main flame detection circuit is connected to the main chip, and the auxiliary flame detection circuit is connected to the auxiliary chip.

[0014] Furthermore, both the main flame detection circuit and the auxiliary flame detection circuit include: a first transformer, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a first varistor, a first amplifier, a first optocoupler, a first power converter, and a first diode;

[0015] Specifically, pin 4 of the first transformer is connected to a 220V_N signal, pin 5 of the first transformer is connected to a 220V_L signal, pin 3 of the first transformer is connected to one end of the first capacitor, and the other end of the first capacitor is connected to one end of the first resistor and one end of the ninth resistor; the other end of the first resistor is connected to one end of the second resistor, the other end of the second resistor is connected to one end of the third resistor, the other end of the third resistor is connected to one end of the fourth resistor and one end of the first varistor, the other end of the fourth resistor is connected to one end of the fifth resistor, the other end of the fifth resistor is connected to one end of the sixth resistor, and the sixth... The other end of the resistor is connected to one end of the seventh resistor and the other end of the first varistor, respectively. The other end of the seventh resistor is connected to one end of the eighth resistor, and the other end of the eighth resistor is grounded. The other end of the ninth resistor is connected to one end of the tenth resistor, and the other end of the tenth resistor is connected to one end of the eleventh resistor. The other end of the eleventh resistor is connected to one end of the twelfth resistor and one end of the second capacitor, respectively. The other end of the twelfth resistor is connected to one end of the thirteenth resistor and one end of the third capacitor, respectively. The other end of the thirteenth resistor is connected to the cathode of the first diode, one end of the fourth capacitor, one end of the sixteenth resistor, one end of the seventeenth resistor, and... The first amplifier's pin 3 is connected to the other end of the second capacitor, the other end of the third capacitor, the anode of the first diode, and the other end of the fourth capacitor, all of which are grounded. The first amplifier's pin 1 is connected to one end of the eighteenth resistor. The other end of the eighteenth resistor is connected to one end of the nineteenth resistor and pin 2 of the first optocoupler. The other end of the nineteenth resistor is connected to pin 1 of the first optocoupler and grounded. Pin 3 of the first optocoupler is grounded. Pin 4 of the first optocoupler is connected to the OUT1 signal. Pin 2 of the first optocoupler is connected to one end of the fifteenth resistor and one end of the fourteenth resistor. Pin 8 of the first optocoupler is connected to one end of the fifth capacitor and the +5V signal. Pins 4, 5, and 6 of the first optocoupler are connected to the other ends of the fifteenth resistor, the seventeenth resistor, and the fifth capacitor, respectively, and grounded. The other end of the fourteenth resistor is connected to the other end of the sixteenth resistor and the second interface of the first power converter. The first power converter's first interface is grounded. Pin 3 of the first power converter is connected to one end of the sixth capacitor and grounded. Pin 4 of the first power converter is connected to the other end of the sixth capacitor and the +5V signal.

[0016] Furthermore, the solenoid valve detection circuit includes a main solenoid valve detection circuit and an auxiliary solenoid valve detection circuit; the main solenoid valve detection circuit is connected to the main chip, the auxiliary solenoid valve detection circuit is connected to the auxiliary chip, and both the main solenoid valve detection circuit and the auxiliary solenoid valve detection circuit receive input signals from the solenoid valve.

[0017] Furthermore, both the main solenoid valve detection circuit and the auxiliary solenoid valve detection circuit include: a twentieth resistor, a twenty-first resistor, a second diode, a second optocoupler, and a seventh capacitor;

[0018] The second resistor is connected to the cathode of the second diode and the first pin of the second optocoupler. The anode of the second diode is connected to the second pin of the second optocoupler and connected to the 220V_N signal. The third pin of the second optocoupler is grounded. The fourth pin of the second optocoupler is connected to one end of the seventh capacitor, one end of the twenty-first resistor, and the Q03_OK1 signal. The other end of the seventh capacitor is grounded, and the other end of the twenty-first resistor is connected to the +3.3V signal.

[0019] Furthermore, the relay includes a main relay and an auxiliary relay. The main relay is connected to the main chip, and the auxiliary relay is connected to the auxiliary chip. The main relay, the auxiliary relay, and the solenoid valve are connected in series. When either the main relay or the auxiliary relay is disconnected, the solenoid valve is open-circuited.

[0020] A gas stove includes the flameout protection device described in any of the above embodiments.

[0021] The beneficial effects of this utility model are as follows: By adopting dual-path detection and dual-drive, the safety hazards caused by the failure of the drive circuit are avoided. Its working principle is that the gas valve control is controlled by two chips that can independently detect flame signals. The main chip and the auxiliary chip can communicate and cooperate with each other. The output contacts of the two relays controlled by the main and auxiliary chips are connected in series. As long as one of them detects that the flame is lost, the entire control system is disconnected, thereby preventing the gas control part from going out of control. In addition, each relay has a detection circuit for the output contacts. When the relay contacts are open or stuck, a warning signal will be issued, maximizing the safety of the gas system. Attached Figure Description

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

[0023] Figure 1 This is a system block diagram of a gas stove flameout protection device according to an embodiment of the present utility model;

[0024] Figure 2 This is a circuit diagram of the main flame detection circuit in a gas stove flameout protection device according to an embodiment of the present utility model;

[0025] Figure 3 This is a circuit diagram of the auxiliary flame detection circuit in a gas stove flameout protection device according to an embodiment of the present utility model;

[0026] Figure 4This is a circuit diagram of the 220V solenoid valve detection mode in a gas stove flameout protection device according to an embodiment of the present utility model.

[0027] Figure 5 This is a circuit diagram of the 24V solenoid valve detection mode in a gas stove flameout protection device according to an embodiment of the present utility model. Detailed Implementation

[0028] The following description and accompanying drawings fully illustrate specific embodiments described herein to enable those skilled in the art to practice them. Some embodiments may include or substitute parts and features of other embodiments. The scope of the embodiments herein encompasses the entire scope of the claims and all available equivalents thereof. Throughout this document, the terms “first,” “second,” etc., are used only to distinguish one element from another without requiring or implying any actual relationship or order between the elements. Indeed, a first element can also be referred to as a second element, and vice versa. Furthermore, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a structure, apparatus, or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a structure, apparatus, or device. Without further limitation, an element defined by the phrase “comprising one…” does not exclude the presence of other identical elements in the structure, apparatus, or device that includes said element. The various embodiments described herein are presented in a progressive manner, with each embodiment focusing on its differences from other embodiments; similar or identical parts between embodiments can be referred to interchangeably.

[0029] The terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer" used in this document to indicate orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings. They are used solely for the convenience of describing the document and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. In the description herein, unless otherwise specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to mechanical or electrical connections, or internal connections between two elements; they can be direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0030] In this document, unless otherwise stated, the term "multiple" means two or more.

[0031] In this article, the character " / " indicates that the objects before and after it are in an "or" relationship. For example, A / B means: A or B.

[0032] In this article, the term "and / or" describes an association between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or A and B.

[0033] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0034] According to an embodiment of the present invention, a flameout protection device for a gas stove is provided.

[0035] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments, such as... Figure 1 As shown, the gas stove flameout protection device according to an embodiment of the present invention includes:

[0036] Control chip, flame detection circuit, solenoid valve detection circuit, relay and solenoid valve;

[0037] The input terminals of the control chip are connected to the flame detection circuit and the solenoid valve detection circuit respectively, the output terminal of the control chip is connected to the relay input terminal, and the relay output terminal is connected to one end of the solenoid valve.

[0038] The control chip receives the flame status signal of the gas stove detected by the flame detection circuit and the solenoid valve working status signal of the solenoid valve detected by the solenoid valve circuit. It determines whether the flame status signal or the solenoid valve working status signal is in a fault state, and controls the relay to control the solenoid valve to open or close the circuit based on the determination result.

[0039] In one embodiment, when either the flame status signal or the solenoid valve operating status signal is a fault status signal, the control chip controls the relay to disconnect the circuit of the solenoid valve.

[0040] It should be noted that the contact detection principle is as follows: when the control chip controls the opening and closing of the relay contacts, it will obtain a feedback signal by collecting the contact voltage through the optocoupler. When the control chip controls the relay to conduct, the relay contacts will return a conduction signal. When the control chip controls the relay contacts to open, the optocoupler should not have a conduction signal; otherwise, it is considered as sticking.

[0041] In one embodiment, the control chip includes a main chip and an auxiliary chip; both the main chip and the auxiliary chip independently control the relay to disconnect the solenoid valve.

[0042] In one embodiment, the flame detection circuit includes a main flame detection circuit and an auxiliary flame detection circuit; the main flame detection circuit is connected to the main chip, and the auxiliary flame detection circuit is connected to the auxiliary chip.

[0043] It should be noted that the flame detection circuit works by continuously detecting the ion needle current signal after ignition. If the current disappears for more than 0.5 seconds, it is considered that the flame has been disconnected.

[0044] In one embodiment, both the main flame detection circuit and the auxiliary flame detection circuit include: a first transformer, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a first varistor, a first amplifier, a first optocoupler, a first power converter, and a first diode;

[0045] Specifically, pin 4 of the first transformer is connected to a 220V_N signal, pin 5 of the first transformer is connected to a 220V_L signal, pin 3 of the first transformer is connected to one end of the first capacitor, and the other end of the first capacitor is connected to one end of the first resistor and one end of the ninth resistor; the other end of the first resistor is connected to one end of the second resistor, the other end of the second resistor is connected to one end of the third resistor, the other end of the third resistor is connected to one end of the fourth resistor and one end of the first varistor, the other end of the fourth resistor is connected to one end of the fifth resistor, the other end of the fifth resistor is connected to one end of the sixth resistor, and the sixth... The other end of the resistor is connected to one end of the seventh resistor and the other end of the first varistor, respectively. The other end of the seventh resistor is connected to one end of the eighth resistor, and the other end of the eighth resistor is grounded. The other end of the ninth resistor is connected to one end of the tenth resistor, and the other end of the tenth resistor is connected to one end of the eleventh resistor. The other end of the eleventh resistor is connected to one end of the twelfth resistor and one end of the second capacitor, respectively. The other end of the twelfth resistor is connected to one end of the thirteenth resistor and one end of the third capacitor, respectively. The other end of the thirteenth resistor is connected to the cathode of the first diode, one end of the fourth capacitor, one end of the sixteenth resistor, one end of the seventeenth resistor, and... The first amplifier's pin 3 is connected to the other end of the second capacitor, the other end of the third capacitor, the anode of the first diode, and the other end of the fourth capacitor, all of which are grounded. The first amplifier's pin 1 is connected to one end of the eighteenth resistor. The other end of the eighteenth resistor is connected to one end of the nineteenth resistor and pin 2 of the first optocoupler. The other end of the nineteenth resistor is connected to pin 1 of the first optocoupler and grounded. Pin 3 of the first optocoupler is grounded. Pin 4 of the first optocoupler is connected to the OUT1 signal. Pin 2 of the first optocoupler is connected to one end of the fifteenth resistor and one end of the fourteenth resistor. Pin 8 of the first optocoupler is connected to one end of the fifth capacitor and the +5V signal. Pins 4, 5, and 6 of the first optocoupler are connected to the other ends of the fifteenth resistor, the seventeenth resistor, and the fifth capacitor, respectively, and grounded. The other end of the fourteenth resistor is connected to the other end of the sixteenth resistor and the second interface of the first power converter. The first power converter's first interface is grounded. Pin 3 of the first power converter is connected to one end of the sixth capacitor and grounded. Pin 4 of the first power converter is connected to the other end of the sixth capacitor and the +5V signal.

[0046] In one embodiment, the solenoid valve detection circuit includes a main solenoid valve detection circuit and an auxiliary solenoid valve detection circuit; the main solenoid valve detection circuit is connected to the main chip, the auxiliary solenoid valve detection circuit is connected to the auxiliary chip, and both the main solenoid valve detection circuit and the auxiliary solenoid valve detection circuit receive input signals from the solenoid valve.

[0047] It should be noted that the principle of the solenoid valve detection circuit is that the solenoid valve detects whether its control circuit has failed. The series relay has a dual-redundancy design to prevent the solenoid valve control circuit from failing.

[0048] In one embodiment, both the main solenoid valve detection circuit and the auxiliary solenoid valve detection circuit include: a twentieth resistor, a twenty-first resistor, a second diode, a second optocoupler, and a seventh capacitor.

[0049] The second resistor is connected to the cathode of the second diode and the first pin of the second optocoupler. The anode of the second diode is connected to the second pin of the second optocoupler and connected to the 220V_N signal. The third pin of the second optocoupler is grounded. The fourth pin of the second optocoupler is connected to one end of the seventh capacitor, one end of the twenty-first resistor, and the Q03_OK1 signal. The other end of the seventh capacitor is grounded, and the other end of the twenty-first resistor is connected to the +3.3V signal.

[0050] In one embodiment, the relay includes a main relay and an auxiliary relay. The main relay is connected to a main chip, and the auxiliary relay is connected to an auxiliary chip. The main relay, the auxiliary relay, and the solenoid valve are connected in series. When either the main relay or the auxiliary relay is disconnected, the solenoid valve is open-circuited.

[0051] The present invention will be described below with reference to the accompanying drawings and specific embodiments.

[0052] In a specific embodiment, such as Figure 2 As shown, the main flame detection circuit includes: transformer T1 (using EI type transformer), capacitor C1 (model CBB630V104J), capacitors C2, C3, C4, C5, and C6, resistors R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18, and R19, varistor RV1 (model VDR-14D911K), amplifier U1 (model TLC27L2CDR), optocoupler U2 (354T optocoupler), power converter U3 (model B0505S-1WR3), and diode D1 (model 1N4148-LL34).

[0053] Specifically, pin 4 of transformer T1 is connected to a 220V_N signal, pin 5 of transformer T1 is connected to a 220V_L signal, pin 3 of transformer T1 is connected to one end of capacitor C1, and the other end of capacitor C1 is connected to one end of resistor R1 and one end of resistor R9; the other end of resistor R1 is connected to one end of resistor R2, the other end of resistor R2 is connected to one end of resistor R3, the other end of resistor R3 is connected to one end of resistor R4 and one end of varistor RV1, the other end of resistor R4 is connected to one end of resistor R5, and the other end of resistor R5 is connected to one end of resistor R6. The other end of R6 is connected to one end of resistor R7 and the other end of varistor RV1. The other end of resistor R7 is connected to one end of resistor R8, and the other end of resistor R8 is grounded. The other end of resistor R9 is connected to one end of resistor R10. The other end of resistor R10 is connected to one end of resistor R11. The other end of resistor R11 is connected to one end of resistor R12 and one end of capacitor C2. The other end of resistor R12 is connected to one end of resistor R13 and one end of capacitor C3. The other end of resistor R13 is connected to the cathode of diode D1, one end of capacitor C4, one end of resistor R16, and one end of resistor R17. The amplifier U1's pin 3 is connected to the other end of capacitor C2, capacitor C3, diode D1's anode, and capacitor C4, and grounded. Amplifier U1's pin 1 is connected to one end of resistor R18. The other end of resistor R18 is connected to one end of resistor R19 and pin 2 of optocoupler U2. The other end of resistor R19 is connected to pin 1 of optocoupler U2 and grounded. Optocoupler U2's pin 3 is grounded. Optocoupler U2's pin 4 is connected to the OUT1 signal. Optocoupler U2's pin 2 is connected to one end of resistor R15 and... One end of R14 is connected, and pin 8 of optocoupler U2 is connected to one end of capacitor C5 and the +5V signal respectively. Pins 4, 5, and 6 of optocoupler U2 are connected to the other ends of resistor R15, resistor R17, and capacitor C5 respectively and grounded. The other end of resistor R14 is connected to the other end of resistor R16 and the second interface of power converter U3. The first interface of power converter U3 is grounded. Pin 3 of power converter U3 is connected to one end of capacitor C6 and grounded. Pin 4 of power converter U3 is connected to the other end of capacitor C6 and the +5V signal respectively.

[0054] Among them, the end of the varistor RV1 connected to the resistor R3 is used for flame detection, and the end of the varistor RV1 connected to the resistor R6 is used to connect to the machine casing.

[0055] like Figure 3As shown, the auxiliary flame detection circuit includes: transformer T2, capacitors C7, C8, C9, C10, C11, and C12, resistors R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, R36, R37, and R38, varistor RV2, amplifier U4, optocoupler U5, power converter U6, and diode D2.

[0056] Specifically, pin 4 of transformer T2 is connected to a 220V_N signal, pin 5 of transformer T2 is connected to a 220V_L signal, pin 3 of transformer T2 is connected to one end of capacitor C7, the other end of capacitor C7 is connected to one end of resistor R20 and one end of resistor R28; the other end of resistor R20 is connected to one end of resistor R21, the other end of resistor R21 is connected to one end of resistor R22, the other end of resistor R22 is connected to one end of resistor R23 and one end of varistor RV2, the other end of resistor R23 is connected to one end of resistor R24, and the other end of resistor R24 ​​is connected to one end of resistor R25. The resistor R25 is connected to one end of resistor R26 and the other end of varistor RV2. The other end of resistor R26 is connected to one end of resistor R27, and the other end of resistor R27 is grounded. The other end of resistor R28 is connected to one end of resistor R29. The other end of resistor R29 is connected to one end of resistor R30. The other end of resistor R30 is connected to one end of resistor R31 and one end of capacitor C8. The other end of resistor R31 is connected to one end of resistor R32 and one end of capacitor C9. The other end of resistor R32 is connected to the cathode of diode D2, one end of capacitor C10, and one end of resistor R35. One end of resistor R36 is connected to pin 3 of amplifier U4; the other ends of capacitors C8 and C9, the anode of diode D2, and the other end of capacitor C10 are connected to ground; pin 1 of amplifier U4 is connected to one end of resistor R37; the other end of resistor R37 is connected to one end of resistor R38 and pin 2 of optocoupler U5; the other end of resistor R38 is connected to pin 1 of optocoupler U5 and grounded; pin 3 of optocoupler U5 is grounded; pin 4 of optocoupler U5 is connected to the OUT2 signal; pin 2 of optocoupler U4 is connected to one end of resistor R34 and... One end of resistor R33 is connected to the optocoupler. Pin 8 of optocoupler U5 is connected to one end of capacitor C11 and the +5V signal. Pins 4, 5, and 6 of optocoupler U5 are connected to the other ends of resistor R34, resistor R36, and capacitor C11, respectively, and are grounded. The other end of resistor R33 is connected to the other end of resistor R35 and the second interface of power converter U6. The first interface of power converter U6 is grounded. Pin 3 of power converter U6 is connected to one end of capacitor C12 and is grounded. Pin 4 of power converter U6 is connected to the other end of capacitor C12 and the +5V signal.

[0057] In addition, the end of the varistor RV2 connected to the resistor R22 is used for flame detection, and the end of the varistor RV1 connected to the resistor R25 is used to connect to the machine casing.

[0058] like Figures 4-5 As shown ( Figure 4 Point A and Figure 5(Point A remains connected). The main solenoid valve detection circuit and the auxiliary solenoid valve detection circuit include: optocoupler U8 (model EL357), optocoupler U9, optocoupler U11, optocoupler U12, capacitor C14, capacitor C15, diode D3, diode D4, resistor R39, resistor R40, resistor R41, resistor R42, resistor R43, resistor R44, resistor R45, resistor R46, resistor R47, and resistor R48.

[0059] Furthermore, the main solenoid valve detection circuit and the auxiliary solenoid valve detection circuit can select different operating modes according to the input voltage, which can be divided into 220V and 24V modes. Among them, optocoupler U8 is used to provide the main 220V solenoid valve detection mode, which is connected and controlled by the main chip; optocoupler U8 is used to provide the auxiliary 220V solenoid valve detection mode, which is connected and controlled by the auxiliary chip; optocoupler U11 is used to provide the main 24V solenoid valve detection mode, which is connected and controlled by the main chip; optocoupler U12 is used to provide the auxiliary 24V solenoid valve detection mode, which is connected and controlled by the auxiliary chip.

[0060] like Figure 4 As shown on the left, the circuit connection for the main 220V solenoid valve detection mode is as follows: one end of resistor R39 is connected to the cathode of diode D3 and pin 1 of optocoupler U8 respectively; the anode of diode D3 is connected to pin 2 of optocoupler U8 and connected to the 220V_N signal; pin 3 of optocoupler U8 is grounded; pin 4 of optocoupler U8 is connected to one end of capacitor C14, one end of resistor R40 and the Q03_OK1 signal respectively; the other end of capacitor C14 is grounded; and the other end of resistor R40 is connected to the +3.3V signal.

[0061] like Figure 4 As shown on the right, the circuit connection for the auxiliary 220V solenoid valve detection mode is as follows: one end of resistor R42 is connected to the cathode of diode D4 and pin 1 of optocoupler U9 respectively; the anode of diode D4 is connected to pin 2 of optocoupler U9 and connected to the 220V_N signal; pin 3 of optocoupler U9 is grounded; pin 4 of optocoupler U9 is connected to one end of capacitor C15, one end of resistor R41 and the Q03_OK2 signal respectively; the other end of capacitor C15 is grounded; and the other end of resistor R41 is connected to the +3.3V signal.

[0062] like Figure 5As shown on the left, the circuit connection for the main 24V solenoid valve detection mode is as follows: one end of resistor R43 is connected to one end of resistor R45 and pin 1 of optocoupler U11; the other end of resistor R45 is connected to pin 2 of optocoupler U11 and grounded; pin 3 of optocoupler U11 is grounded; pin 4 of optocoupler U11 is connected to one end of resistor R44 and the Q08_OK1 signal; and the other end of resistor R44 is connected to a +3.3V signal.

[0063] like Figure 5 As shown on the right, the circuit connection for the auxiliary 24V solenoid valve detection mode is as follows: one end of resistor R47 is connected to one end of resistor R48 and pin 1 of optocoupler U12; the other end of resistor R48 is connected to pin 2 of optocoupler U12 and grounded; pin 3 of optocoupler U12 is grounded; pin 4 of optocoupler U12 is connected to one end of resistor R46 and the Q08_OK2 signal; and the other end of resistor R46 is connected to a +3.3V signal.

[0064] Among them, the Q03_OK1 signal, Q03_OK2 signal, Q08_OK1 signal and Q08_OK2 signal are solenoid valve input signals from the solenoid valve.

[0065] To facilitate understanding of the above-mentioned technical solutions of this utility model, the working principle or operation method of this utility model in actual process will be described in detail below.

[0066] In practical applications, an independent architecture is adopted for the main chip and auxiliary chip, which interact with each other via a communication connection. The main chip receives signals from the main flame detection circuit and the main solenoid valve, while the auxiliary chip receives signals from the auxiliary flame detection circuit and the auxiliary solenoid valve. This dual-system redundancy design significantly improves safety and fault tolerance; a failure in any control chip will not cause the overall protection to fail. The main relay and auxiliary relay are connected in series to the solenoid valve, forming an AND gate logic: the solenoid valve can only be energized and operate when both are closed simultaneously. If either relay is disconnected (e.g., the main chip detects flame extinction or solenoid valve malfunction), the solenoid valve power supply circuit is cut off, and the gas passage is closed. Both the flame detection signal and the solenoid valve status signal are acquired through two independent circuits (main circuit and auxiliary circuit), and the chip eliminates the possibility of misjudgment by comparing the consistency of the two signals. For example, the main flame detection circuit and the auxiliary flame detection circuit have the same structure, which can cross-verify the presence of the flame.

[0067] The user presses the knob to start ignition, and the flame detection circuit monitors the flame status in real time via a thermocouple or ionization sensor (depending on the specific design). The main chip and auxiliary chip simultaneously receive flame signals and solenoid valve feedback signals. If both are determined to be normal, a high-level signal is output to drive their respective relays to close, and the solenoid valve remains open to supply gas.

[0068] During the operation monitoring phase, the main / auxiliary chips continuously monitor the flame signal and solenoid valve current: Flame extinguishing: If the flame detection circuit senses a temperature drop (thermocouple type) or an interruption of ion current (ionization type), the chip immediately sends a shutdown command. Solenoid valve failure: If the solenoid valve detection circuit detects an abnormal current (such as a short circuit or open circuit), the chip also triggers the relay to disconnect. That is, after any control chip triggers a fault judgment, the relay it controls immediately disconnects, interrupting the series circuit and causing the solenoid valve to close.

[0069] In summary, by employing the above-mentioned technical solution of this utility model, the safety hazards caused by the failure of the drive circuit are avoided by adopting dual-path detection and dual-drive. Its working principle is that the gas valve control is controlled separately by two chips that can independently detect flame signals. The main chip and the auxiliary chip can exchange information and cooperate. The output contacts of the two relays controlled by the main and auxiliary chips are connected in series. As long as one of them detects the loss of flame, the entire control system is disconnected, thereby preventing the gas control part from going out of control. In addition, each relay has a detection circuit for the output contacts. When the relay contacts are open or stuck, a warning signal will be issued, maximizing the safety of the gas system.

[0070] In other embodiments, the present invention also provides a gas stove that includes the flameout protection device described in any of the above embodiments.

[0071] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A gas hob flame failure protection device, characterized in that include: Control chip, flame detection circuit, solenoid valve detection circuit, relay and solenoid valve; The input terminal of the control chip is connected to the flame detection circuit and the solenoid valve detection circuit respectively, the output terminal of the control chip is connected to the input terminal of the relay, and the output terminal of the relay is connected to one end of the solenoid valve. The control chip receives the flame status signal of the gas stove detected by the flame detection circuit and the electromagnetic working status signal of the solenoid valve detected by the solenoid valve circuit, determines whether the flame status signal or the solenoid valve working status signal is in a fault state, and controls the relay to control the solenoid valve to open and close the circuit based on the determination result. The control chip includes a main chip and an auxiliary chip; both the main chip and the auxiliary chip independently control the relay to disconnect the solenoid valve; the flame detection circuit includes a main flame detection circuit and an auxiliary flame detection circuit; the main flame detection circuit is connected to the main chip, and the auxiliary flame detection circuit is connected to the auxiliary chip.

2. A flame failure protection device for a gas hob according to claim 1, characterised in that When either the flame status signal or the electromagnetic operating status signal is a fault status signal, the control chip controls the relay to disconnect the circuit of the solenoid valve.

3. A flame failure protection device for a gas hob according to claim 1, characterised in that Both the main flame detection circuit and the auxiliary flame detection circuit include: a first transformer, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a first varistor, a first amplifier, a first optocoupler, a first power converter, and a first diode; Specifically, pin 4 of the first transformer is connected to a 220V_N signal, pin 5 of the first transformer is connected to a 220V_L signal, pin 3 of the first transformer is connected to one end of the first capacitor, and the other end of the first capacitor is connected to one end of the first resistor and one end of the ninth resistor; the other end of the first resistor is connected to one end of the second resistor, the other end of the second resistor is connected to one end of the third resistor, the other end of the third resistor is connected to one end of the fourth resistor and one end of the first varistor, the other end of the fourth resistor is connected to one end of the fifth resistor, the other end of the fifth resistor is connected to one end of the sixth resistor, and the sixth... The other end of the resistor is connected to one end of the seventh resistor and the other end of the first varistor, respectively. The other end of the seventh resistor is connected to one end of the eighth resistor, and the other end of the eighth resistor is grounded. The other end of the ninth resistor is connected to one end of the tenth resistor, and the other end of the tenth resistor is connected to one end of the eleventh resistor. The other end of the eleventh resistor is connected to one end of the twelfth resistor and one end of the second capacitor, respectively. The other end of the twelfth resistor is connected to one end of the thirteenth resistor and one end of the third capacitor, respectively. The other end of the thirteenth resistor is connected to the cathode of the first diode, one end of the fourth capacitor, one end of the sixteenth resistor, one end of the seventeenth resistor, and... The first amplifier's pin 3 is connected to the other end of the second capacitor, the other end of the third capacitor, the anode of the first diode, and the other end of the fourth capacitor, all of which are grounded. The first amplifier's pin 1 is connected to one end of the eighteenth resistor. The other end of the eighteenth resistor is connected to one end of the nineteenth resistor and pin 2 of the first optocoupler. The other end of the nineteenth resistor is connected to pin 1 of the first optocoupler and grounded. Pin 3 of the first optocoupler is grounded. Pin 4 of the first optocoupler is connected to the OUT1 signal. Pin 2 of the first optocoupler is connected to one end of the fifteenth resistor and one end of the fourteenth resistor. Pin 8 of the first optocoupler is connected to one end of the fifth capacitor and the +5V signal. Pins 4, 5, and 6 of the first optocoupler are connected to the other ends of the fifteenth resistor, the seventeenth resistor, and the fifth capacitor, respectively, and grounded. The other end of the fourteenth resistor is connected to the other end of the sixteenth resistor and the second interface of the first power converter. The first power converter's first interface is grounded. Pin 3 of the first power converter is connected to one end of the sixth capacitor and grounded. Pin 4 of the first power converter is connected to the other end of the sixth capacitor and the +5V signal.

4. A flame failure protection device for a gas hob according to claim 3, characterised in that The solenoid valve detection circuit includes a main solenoid valve detection circuit and an auxiliary solenoid valve detection circuit; the main solenoid valve detection circuit is connected to the main chip, the auxiliary solenoid valve detection circuit is connected to the auxiliary chip, and both the main solenoid valve detection circuit and the auxiliary solenoid valve detection circuit receive input signals from the solenoid valve.

5. A flame failure protection device for a gas hob according to claim 4, characterised in that Both the main solenoid valve detection circuit and the auxiliary solenoid valve detection circuit include: a twentieth resistor, a twenty-first resistor, a second diode, a second optocoupler, and a seventh capacitor; In this configuration, one end of the second resistor is connected to the cathode of the second diode and the first pin of the second optocoupler, the anode of the second diode is connected to the second pin of the second optocoupler and connected to a 220V_N signal, the third pin of the second optocoupler is grounded, the fourth pin of the second optocoupler is connected to one end of the seventh capacitor, one end of the eleventh resistor and the Q03_OK1 signal, the other end of the seventh capacitor is grounded, and the other end of the eleventh resistor is connected to a +3.3V signal.

6. A flame failure protection device for a gas hob as defined in claim 5, characterized in that The relay includes a main relay and an auxiliary relay. The main relay is connected to the main chip, and the auxiliary relay is connected to the auxiliary chip. The main relay, the auxiliary relay, and the solenoid valve are connected in series. When either the main relay or the auxiliary relay is disconnected, the solenoid valve is open-circuited.

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