Power-off flameout protection circuit and kitchen appliance

Abstract

The utility model provides a power-off flameout protection circuit and a kitchen appliance. The kitchen appliance comprises a coil and a thermocouple, the power-off flameout protection circuit comprises a first switching circuit, a second switching circuit, a first one-way energy storage circuit and a second one-way energy storage circuit. And when the second switching circuit is in an on state and the second one-way energy storage circuit releases electric energy, current formed by the electric energy released by the second one-way energy storage circuit and current generated by the thermoelectric force in the coil counteract each other, so that the valve body of the kitchen appliance is closed, and the thermocouple stops generating the thermoelectric force. The power-off flameout protection can be performed on the gas stove (or the integrated stove) powered by the power adapter in a power-off state, so that the potential safety hazard is eliminated, and the experience feeling of a user is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic circuits, in particular to a power-off flameout protection circuit and a kitchen appliance. Background Art

[0002] In the prior art, the closure of the valve body of a household gas stove (or integrated stove) after ignition is usually maintained by the thermoelectric potential generated by a thermocouple, and does not need to rely on its own power supply to maintain it continuously. This can save electricity for battery-powered gas stoves. For gas stoves (or integrated stoves) powered by a power adapter, when the mains power is cut off or tripped, the combustion state will continue to be maintained without extinguishing the flame. However, if the gas stove (or integrated stove) itself has intelligent timing, anti-dry burning or other protection functions, these functions will fail after the power is cut off, and the gas stove (or integrated stove) will be in a continuous combustion state, which poses certain safety hazards and a poor user experience. Utility Model Content

[0003] In view of this, the purpose of the present invention is to provide a power-off flameout protection circuit and a kitchen appliance to ensure that a gas stove (or integrated stove) powered by a power adapter can be protected from power-off flameout when the device is powered off, thereby eliminating safety hazards and improving the user experience.

[0004] In a first aspect, an embodiment of the present invention provides a power-off and flameout protection circuit, which is applied to a kitchen appliance, the kitchen appliance including: a coil and a thermocouple; the power-off and flameout protection circuit including: a first switch circuit, a second switch circuit, a first unidirectional energy storage circuit, and a second unidirectional energy storage circuit; the first switch circuit and the second switch circuit are connected in sequence, the power supply, the first unidirectional energy storage circuit and the second switch circuit are connected in sequence, the power supply, the second unidirectional energy storage circuit and the second switch circuit are connected in sequence, and the second switch circuit, the coil and the thermocouple are connected in pairs; the first switch circuit is used to determine the open state or the closed state based on the valve opening signal; the second switch circuit is used to determine the open state or the closed state based on the first switch circuit and the first unidirectional energy storage circuit; the first unidirectional energy storage circuit and the second unidirectional energy storage circuit are both used to store or release electrical energy based on the power supply.

[0005] In the preferred embodiment provided by the present invention, when the kitchen appliance is in a burning state and the valve opening signal is not 0, the power supply is not 0, the first switch circuit is in an open state, the first unidirectional energy storage circuit and the second unidirectional energy storage circuit store electrical energy, and the second switch circuit is in a closed state.

[0006] In the preferred embodiment provided by the present invention, when the kitchen appliance is in a power-off state, the valve opening signal and the power supply are 0, the first switch circuit is in a closed state, the first unidirectional energy storage circuit and the second unidirectional energy storage circuit release electrical energy, and the second switch circuit is in an open state.

[0007] In a preferred embodiment provided by the present utility model, the above-mentioned first switching circuit includes: a third resistor, a fourth resistor and a second triode, the base of the second triode is connected to the third resistor, and the base of the second triode, the fourth resistor and the emitter of the second triode are connected in sequence; the second switching circuit includes: a first field effect transistor; the first unidirectional energy storage circuit includes: a first diode, a second resistor and a first power capacitor, the first diode is connected to the first power capacitor, and the second resistor is connected to the first power capacitor; the second unidirectional energy storage circuit includes: a second diode, a first resistor and a second power capacitor, the second diode is connected to the second power capacitor, and the first resistor is connected to the second power capacitor.

[0008] In a preferred embodiment provided by the present invention, when the kitchen appliance is in a burning state, the power supply stores electrical energy in the first power capacitor and the second power capacitor, the second transistor is turned on, and the first field effect transistor is turned off.

[0009] In a preferred embodiment provided by the present invention, when the kitchen appliance is in a power-off state, the first power capacitor and the second power capacitor release electrical energy, the second transistor is turned off, and the first field-effect transistor is turned on.

[0010] In a preferred embodiment provided by the present invention, the resistance values of the third resistor and the fourth resistor are both determined based on the level of the valve opening signal.

[0011] In a preferred embodiment provided by the present invention, the first resistor and the second resistor are current limiting resistors, the first resistor is used to reduce the instantaneous charging current of the second power capacitor, and the second resistor is used to reduce the instantaneous charging current of the first power capacitor.

[0012] In a preferred embodiment provided by the present invention, the above-mentioned kitchen appliance includes: a gas stove or an integrated stove with a single-coil solenoid valve.

[0013] In a second aspect, the embodiments of the present invention further provide a kitchen appliance, which includes the embodiments of the present invention and brings the following beneficial effects:

[0014] The present invention provides a power-off flameout protection circuit and a kitchen appliance. When the second switch circuit is on and the second unidirectional energy storage circuit releases electrical energy, the current generated by the energy released by the second unidirectional energy storage circuit offsets the current generated by the thermoelectric potential within the coil, closing the valve of the kitchen appliance and stopping the thermoelectric potential generated by the thermocouple. This ensures that a gas stove (or integrated stove) powered by a power adapter can be protected from power failure when the device is powered off, eliminating safety hazards and improving the user experience.

[0015] Other features and advantages of the present disclosure will be set forth in the following description, or some features and advantages may be inferred or unambiguously determined from the description, or may be learned by practicing the above-mentioned technology of the present disclosure.

[0016] In order to make the above-mentioned objectives, features and advantages of the present disclosure more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 A schematic structural diagram of a power-off flameout protection circuit provided by an embodiment of the present utility model;

[0019] Figure 2 A schematic diagram of a circuit state of a power-off flameout protection circuit when a gas stove is in a combustion state provided by an embodiment of the utility model;

[0020] Figure 3 A schematic diagram of a circuit state of a power-off flameout protection circuit of a gas stove provided by an embodiment of the present utility model when the gas stove is in a power-off state;

[0021] Figure 4 A circuit diagram of a power-off flameout protection circuit provided by an embodiment of the utility model;

[0022] Figure 5 The present invention provides a structural diagram of a kitchen appliance according to an embodiment of the present invention.

[0023] Icon: 100-kitchen appliance; 11-coil; 12-thermocouple; 200-power-off protection circuit; 21-first switch circuit; 22-second switch circuit; 23-first unidirectional energy storage circuit; 24-second unidirectional energy storage circuit; 3-valve opening signal; 4-power supply; 5-valve body. DETAILED DESCRIPTION

[0024] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0025] At present, the valve body closure of a household gas stove (or integrated stove) after ignition is usually maintained by the thermoelectric potential generated by a thermocouple, and does not need to rely on its own power supply to maintain continuous maintenance. This can save electricity for battery-powered gas stoves. For gas stoves (or integrated stoves) powered by a power adapter, when the mains power is cut off or tripped, the combustion state will continue to be maintained without extinguishing the flame. However, if the gas stove (or integrated stove) itself has intelligent timing, anti-dry burning or other protection functions, these functions will become ineffective after the power is cut off, and the gas stove (or integrated stove) will be in a continuous combustion state, posing certain safety risks and a poor user experience.

[0026] Based on this, the embodiments of the present invention provide a power-off and flameout protection circuit and a kitchen appliance, specifically providing a power-off and flameout protection circuit for a gas stove, ensuring that the gas stove (or integrated stove) powered by a power adapter can perform power-off and flameout protection when the device is powered off, thereby eliminating safety hazards and improving the user experience.

[0027] To facilitate understanding of this embodiment, a power-off flameout protection circuit disclosed in an embodiment of the present utility model is first introduced in detail.

[0028] Example 1:

[0029] The present invention provides a power failure flameout protection circuit for kitchen appliances. Figure 1 The schematic diagram of a power-off flameout protection circuit shown in FIG. 1 shows a kitchen appliance 100 including a coil 11 and a thermocouple 12; a power-off flameout protection circuit 200 including a first switch circuit 21, a second switch circuit 22, a first unidirectional energy storage circuit 23, and a second unidirectional energy storage circuit 24.

[0030] The first switch circuit 21 and the second switch circuit 22 are connected in sequence, the power supply 4, the first unidirectional energy storage circuit 23 and the second switch circuit 22 are connected in sequence, the power supply 4, the second unidirectional energy storage circuit 24 and the second switch circuit 22 are connected in sequence, and the second switch circuit 22, the coil 11 and the thermocouple 12 are connected in pairs;

[0031] The first switching circuit is used to determine the open state or the closed state based on the valve opening signal 3; the second switching circuit is used to determine the open state or the closed state based on the first switching circuit and the first unidirectional energy storage circuit; the first unidirectional energy storage circuit and the second unidirectional energy storage circuit are both used to store electrical energy or release electrical energy based on the power supply.

[0032] When the second switch circuit is in the on state and the second unidirectional energy storage circuit releases electrical energy, the current generated by the electrical energy released by the second unidirectional energy storage circuit and the current generated by the thermoelectric potential in the coil offset each other, so that the valve body of the kitchen appliance is closed and the thermocouple stops generating thermoelectric potential.

[0033] The kitchen appliance in this embodiment may include a gas stove or an integrated stove with a single-coil solenoid valve.

[0034] The power failure protection circuit provided by the embodiment of the present utility model is mainly applicable to single coil solenoid valves. Figure 1 As shown, the first switch circuit 21 is controlled by the valve opening signal 3, and 1 is its control end; the second switch circuit 22 is jointly controlled by the first switch circuit 21 and the first unidirectional energy storage circuit 23, and 2 is its control end; when the gas stove is burning, the thermocouple 12 can convert heat into thermoelectric potential to power the coil 11, and the coil 11 converts it into magnetic force to open the valve body, thereby controlling the on and off of the gas outlet valve.

[0035] This embodiment of the utility model provides a power-off flameout protection circuit. When the second switch circuit is in the on state and the second unidirectional energy storage circuit releases electrical energy, the current generated by the electrical energy released by the second unidirectional energy storage circuit and the current generated by the thermoelectric potential in the coil offset each other, closing the valve body of the kitchen appliance and stopping the thermocouple from generating thermoelectric potential. This ensures that the power-off flameout protection can be implemented when the gas stove (or integrated stove) powered by the power adapter is powered off, thereby eliminating safety hazards and improving the user experience.

[0036] Example 2:

[0037] An embodiment of the present utility model provides another power-off and flameout protection circuit. In some embodiments, when the kitchen appliance is in a burning state and the valve opening signal is not 0, the power supply is not 0, the first switch circuit is in an open state, the first unidirectional energy storage circuit and the second unidirectional energy storage circuit store electrical energy, and the second switch circuit is in a closed state.

[0038] See also Figure 2The diagram shows a circuit state diagram of a power-off flameout protection circuit when a gas stove is in a burning state. When the gas stove is in a normal burning state, the valve opening signal 3 controls the first switch circuit 21 to open, and the first unidirectional energy storage circuit 23 and the second unidirectional energy storage circuit 24 perform normal energy storage. At this time, since the first switch circuit 21 is in the open state, the second switch circuit 22 is in the closed state. At this time, the thermocouple 12 and the coil 11 independently form a power supply circuit, that is, the thermocouple 12 converts the heat of the flame combustion / radiation into thermoelectric potential, and the coil 11 converts it into magnetic force to attract the valve body 5, and the outlet valve opens.

[0039] In some embodiments, when the kitchen appliance is in a power-off state, the valve opening signal and the power supply are 0, the first switch circuit is in a closed state, the first unidirectional energy storage circuit and the second unidirectional energy storage circuit release electrical energy, and the second switch circuit is in an open state.

[0040] See also Figure 3 The circuit state diagram of the power-off flameout protection circuit of a gas stove when it is in a power-off state is shown. When the gas stove is powered off, the valve opening signal 3 and the power supply 4 are both zero. At this time, the first switch circuit 21 is closed, and the control end 2 of the second switch circuit 22 is controlled by the first unidirectional energy storage circuit 23. At this time, the second switch circuit 22 is opened, and the power of the second unidirectional energy storage circuit 24 is released, forming a reverse current opposite to the current generated by the thermoelectric potential in the coil 11. After the currents cancel each other out, there is no electricity in the coil 11 that can be converted into magnetic force, so that the valve body 5 is closed due to its own stress, the air outlet valve is closed, the flame is extinguished, and the thermocouple 12 continues to function due to the lack of flame heat energy, so that the thermoelectric potential gradually becomes zero. After the power of the second unidirectional energy storage circuit 24 is released, the energy is zero, and the entire system is shut down.

[0041] See also Figure 4 The circuit diagram of a power-off flameout protection circuit shown in FIG. 1 includes a first switching circuit comprising: a third resistor R3, a fourth resistor R4, and a second transistor Q2, wherein the base of the second transistor Q2 is connected to the third resistor R3, and the base of the second transistor Q2, the fourth resistor R4, and the emitter of the second transistor Q2 are connected in sequence. The second switching circuit includes: a first field-effect transistor Q1. The first unidirectional energy storage circuit includes: a first diode D1, a second resistor R2, and a first power capacitor CE1, wherein the first diode D1 is connected to the first power capacitor CE1, and the second resistor R2 is connected to the first power capacitor CE1. The second unidirectional energy storage circuit includes: a second diode D2, the first resistor R1, and a second power capacitor CE2, wherein the second diode D2 is connected to the second power capacitor CE2, and the first resistor R1 is connected to the second power capacitor CE2. In addition, L1 is a coil.

[0042] In some embodiments, when the kitchen appliance is in a burning state, the power supply stores electrical energy in the first power capacitor and the second power capacitor, the second transistor is turned on, and the first field effect transistor is turned off.

[0043] like Figure 4 As shown, when the gas stove is burning normally, the power supply VDD charges the first power capacitor CE1 and the second power capacitor CE2 normally to store energy. At this time, the valve opening signal is at a high level, the second transistor Q2 is turned on, the G end of the first field effect transistor Q1 is at a low level, the first field effect transistor Q1 is turned off, and the thermoelectric potential generated by the thermocouple supplies power to the coil L1 to form a power supply circuit.

[0044] In some embodiments, when the kitchen appliance is in a power-off state, the first power capacitor and the second power capacitor release electrical energy, the second transistor is turned off, and the first field-effect transistor is turned on.

[0045] like Figure 4 As shown, when the gas stove loses power, the power supply VDD and the valve opening signal are both pulled low. At this time, the second transistor Q2 is turned off, and the G end of the first field effect transistor Q1 is provided with a high level by the first power capacitor CE1 through the pull-up resistor R2. At this time, the first field effect transistor Q1 is turned on, and the second power capacitor CE2 forms a reverse current opposite to the current generated by the thermoelectric potential in the original coil L1 through the first field effect transistor Q1, so that the coil L1 is turned off and the flame is extinguished.

[0046] In some embodiments, the resistance values of the third resistor and the fourth resistor are both determined based on the level of the valve-opening signal.

[0047] like Figure 4 As shown, the first diode D1 and the second diode D2 prevent current backflow, ensuring that when the power is off, the energy in the first power capacitor CE1 and the second power capacitor CE2 will not be released to the previous circuit, ensuring that the first power capacitor CE1 has enough energy to provide a voltage level to the first field effect transistor Q1, and that the second power capacitor CE2 has enough energy to form a reverse current to close the valve body. The values of the third resistor R3 and the fourth resistor R4 need to be selected according to the voltage level of the valve opening signal, ensuring that when the valve opening signal is high, the second transistor Q2 is in the open state, and when the valve opening signal is low, the second transistor Q2 is in the closed state, while also taking into account that the current of the valve opening signal is as small as possible. Typically, R3 = 1K and R4 = 10K.

[0048] In some embodiments, the first resistor and the second resistor are current limiting resistors, the first resistor is used to reduce the instantaneous charging current of the second power capacitor, and the second resistor is used to reduce the instantaneous charging current of the first power capacitor.

[0049] like Figure 4As shown, the first resistor R1 and the second resistor R2 may be current limiting resistors, which are mainly used to reduce the instantaneous charging current of the first power capacitor CE1 and the second power capacitor CE2 when powered on to prevent device damage.

[0050] This embodiment provides a power-off and flameout protection circuit suitable for a single-coil valve body, ensuring that a gas stove (or integrated stove) powered by a power adapter can be protected from power failure when the device is powered off, thereby eliminating safety hazards and improving the user experience.

[0051] Example 3:

[0052] The present invention provides a kitchen appliance. Figure 5 The structural diagram of a kitchen appliance shown is a kitchen appliance 100, which includes: the power-off and flameout protection circuit 200 provided in the above embodiment.

[0053] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working process of the kitchen appliance described above can refer to the corresponding process in the aforementioned embodiment and will not be repeated here.

[0054] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating positions or relationships, are based on the positions or relationships shown in the accompanying drawings and are intended solely to facilitate the description of this utility model and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A power failure flameout protection circuit, characterized in that: Applicable to a kitchen appliance, the kitchen appliance comprising: a coil and a thermocouple; the power-off flameout protection circuit comprising: a first switch circuit, a second switch circuit, a first unidirectional energy storage circuit, and a second unidirectional energy storage circuit; The first switch circuit and the second switch circuit are connected in sequence, the power supply, the first unidirectional energy storage circuit and the second switch circuit are connected in sequence, the power supply, the second unidirectional energy storage circuit and the second switch circuit are connected in sequence, and the second switch circuit, the coil and the thermocouple are connected in pairs; The first switch circuit is used to determine an open state or a closed state based on a valve opening signal; The second switch circuit is configured to determine an on state or a off state based on the first switch circuit and the first unidirectional energy storage circuit; The first unidirectional energy storage circuit and the second unidirectional energy storage circuit are both used to store electrical energy or release electrical energy based on the power supply.

2. The power-off flameout protection circuit according to claim 1, characterized in that: When the kitchen appliance is in a burning state and the valve opening signal is not 0, the power supply is not 0, the first switch circuit is in an open state, the first unidirectional energy storage circuit and the second unidirectional energy storage circuit store electrical energy, and the second switch circuit is in a closed state.

3. The power-off flameout protection circuit according to claim 1, characterized in that: When the kitchen appliance is in a power-off state, the valve opening signal and the power supply are 0, the first switch circuit is in a closed state, the first unidirectional energy storage circuit and the second unidirectional energy storage circuit release electrical energy, and the second switch circuit is in an open state.

4. The power-off flameout protection circuit according to any one of claims 1 to 3, characterized in that: The first switch circuit includes: a third resistor, a fourth resistor, and a second transistor, the base of the second transistor is connected to the third resistor, and the base of the second transistor, the fourth resistor, and the emitter of the second transistor are connected in sequence; The second switch circuit includes: a first field effect transistor; The first unidirectional energy storage circuit includes: a first diode, a second resistor and a first power capacitor, the first diode is connected to the first power capacitor, and the second resistor is connected to the first power capacitor; The second unidirectional energy storage circuit includes: a second diode, a first resistor, and a second power capacitor. The second diode is connected to the second power capacitor, and the first resistor is connected to the second power capacitor.

5. The power-off flameout protection circuit according to claim 4, characterized in that: When the kitchen appliance is in a burning state, the power supply stores electrical energy for the first power capacitor and the second power capacitor, the second transistor is turned on, and the first field effect transistor is turned off.

6. The power-off flameout protection circuit according to claim 4, characterized in that: When the kitchen appliance is in a power-off state, the first power capacitor and the second power capacitor release electrical energy, the second transistor is turned off, and the first field-effect transistor is turned on.

7. The power-off flameout protection circuit according to claim 4, characterized in that: The resistance values of the third resistor and the fourth resistor are both determined based on the level of the valve opening signal.

8. The power-off flameout protection circuit according to claim 4, characterized in that: The first resistor and the second resistor are current limiting resistors. The first resistor is used to reduce the instantaneous charging current of the second power capacitor, and the second resistor is used to reduce the instantaneous charging current of the first power capacitor.

9. The power failure and flameout protection circuit according to claim 1, characterized in that: The kitchen appliance includes a gas stove or an integrated stove with a single-coil solenoid valve.

10. A kitchen appliance, characterized in that: The kitchen appliance comprises the power-off and flameout protection circuit according to any one of claims 1 to 9.

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