Constant-voltage alternating-current signal generating circuit and combustion equipment

Abstract

The utility model relates to the technical field of voltage conversion, and discloses a constant-voltage alternating-current signal generating circuit and combustion equipment, and the constant-voltage alternating-current signal generating circuit comprises a voltage conversion module and a voltage stabilization module, the voltage stabilizing module comprises a charging capacitor and a voltage stabilizing tube; wherein one end of the charging capacitor is respectively connected with the output end of the voltage conversion module and the first end of the voltage-regulator tube, and the other end of the charging capacitor is respectively connected with the voltage feedback end of the voltage conversion module and the second end of the voltage-regulator tube and is grounded; the first end of the voltage stabilizing tube serves as the output end of the voltage stabilizing module and is used for outputting an alternating-current voltage signal. Therefore, the output AC voltage signal is fed back through the voltage-regulator tube, so that the voltage conversion module can control voltage conversion according to the feedback of the voltage-regulator tube received by the voltage feedback end, closed-loop control of the output AC voltage signal is formed, and the AC voltage signal is ensured to be constant.

Description

Technical Field

[0001] This utility model relates to the field of voltage conversion technology, and in particular to a constant voltage AC signal generating circuit and a combustion device. Background Technology

[0002] Gas water heaters are widely used, and constant-voltage AC signals are involved in both the ignition circuit and flame ionization signal detection processes. However, in related technologies, constant-voltage AC signals typically employ open circuit structures, resulting in unstable peak voltages. This significantly impacts the accuracy and sensitivity of some signal detection during gas water heater operation, even affecting safety. For example, in flame ionization signal detection, due to performance variations in components and the open circuit structure, different AC signal sources output voltage values ​​that fluctuate within a certain range. This hinders precise detection of the flame ionization signal, affecting its sensitivity, and in severe cases, can lead to safety issues due to delayed detection. Therefore, improving the stability of AC signal sources is a pressing technical problem that needs to be addressed. Utility Model Content

[0003] The first technical problem solved by this invention is to provide a constant voltage AC signal generating circuit, which effectively solves the problem of poor stability of AC signal sources.

[0004] The second technical problem solved by this invention is to provide a combustion device that effectively solves the problem of poor stability of AC signal sources.

[0005] The first technical problem mentioned above is solved by the following technical solution:

[0006] A constant voltage AC signal generating circuit includes:

[0007] Voltage conversion module and voltage regulation module;

[0008] The voltage regulator module includes: a charging capacitor and a Zener diode;

[0009] One end of the charging capacitor is connected to the output terminal of the voltage conversion module and the first terminal of the Zener diode, respectively, and the other end is connected to the voltage feedback terminal of the voltage conversion module and the second terminal of the Zener diode, respectively, and grounded.

[0010] The first terminal of the Zener diode serves as the output terminal of the voltage regulator module, used to output an AC voltage signal.

[0011] Compared with the prior art, the constant voltage AC signal generating circuit of this utility model has the following advantages: by setting a Zener diode in the voltage regulator module, and setting the first end of the Zener diode to be connected to one end of the charging capacitor and the output terminal of the voltage output module respectively, and the second end to be connected to the other end of the charging capacitor and the voltage feedback terminal of the voltage conversion module respectively, the Zener diode provides feedback to the output AC voltage signal, so that the voltage conversion module can control the voltage conversion according to the feedback of the Zener diode received by the voltage feedback terminal, forming a closed-loop control of the output AC voltage signal, and ensuring that the AC voltage signal is constant.

[0012] In one embodiment, the voltage conversion module includes: a pulse unit, a transformer unit, a switching unit, and a rectifier unit;

[0013] The output terminal of the pulse unit is connected to the first terminal of the switching unit;

[0014] The input terminal of the transformer unit is connected to the second terminal of the switching unit, and the output terminal of the transformer unit is connected to one end of the rectifier unit.

[0015] The other end of the rectifier unit is connected to one end of the charging capacitor and the first end of the Zener diode, respectively.

[0016] The third terminal of the switching unit serves as the voltage feedback terminal of the voltage conversion module, and is connected to the other end of the charging capacitor and the second terminal of the Zener diode, respectively, and grounded.

[0017] In one embodiment, the transformer unit includes the primary winding and secondary winding of the transformer, and the pulse unit includes the feedback winding of the transformer.

[0018] One end of the feedback winding is connected to the power supply, and the other end is connected to the first end of the switching unit.

[0019] One end of the primary winding is connected to the power supply, and the other end is connected to the second end of the switching unit.

[0020] One end of the secondary winding is connected to one end of the rectifier unit, and the other end is grounded.

[0021] In one embodiment, the transformer unit includes a primary winding and a secondary winding of a transformer, and the pulse unit includes a pulse signal generator;

[0022] The pulse signal generator is connected to the first terminal of the switching unit;

[0023] One end of the primary winding is connected to the power supply, and the other end is connected to the second end of the switching unit.

[0024] One end of the secondary winding is connected to one end of the rectifier unit, and the other end is grounded.

[0025] In one embodiment, the transformer unit includes an I-shaped inductor, and the pulse unit includes a pulse signal generator;

[0026] The pulse signal generator is connected to the first terminal of the switching unit;

[0027] One end of the I-shaped inductor is connected to the power supply, and the other end is connected to one end of the charging capacitor, one end of the Zener diode, and the second end of the switching unit, respectively.

[0028] In one embodiment, the voltage conversion module includes a voltage divider unit, a transformer unit, and a switching unit; the transformer unit includes an I-shaped inductor, and the voltage divider unit includes a first voltage divider resistor, a second voltage divider resistor, a current limiting resistor, and a second diode;

[0029] One end of the first voltage divider resistor is connected to the power supply, and the other end is connected to the second terminal of the switching unit and one end of the second voltage divider resistor, respectively.

[0030] The other end of the second voltage divider resistor is connected to one end of the current limiting resistor and one end of the second diode, respectively.

[0031] The other end of the current-limiting resistor is connected to the first end of the switching unit;

[0032] The other end of the second diode is connected to the other end of the charging capacitor and the second end of the Zener diode, and then grounded;

[0033] One end of the I-shaped inductor is connected to the third terminal of the switching unit, and the other end is connected to one end of the charging capacitor and the first terminal of the Zener diode, respectively.

[0034] In one embodiment, the switching unit includes: a transistor, a first resistor, and a second capacitor;

[0035] Among them, the transistor is a current-type device; the first terminal of the transistor is connected to one end of the first resistor and one end of the second capacitor respectively, the second terminal is connected to the input terminal of the transformer unit, and the third terminal is connected to ground;

[0036] The other end of the first resistor is connected to the pulse unit;

[0037] The other end of the second capacitor is connected to ground.

[0038] In one embodiment, the switching unit includes: a transistor, a first resistor, and a second resistor;

[0039] Among them, the transistor is a voltage-type device; the first terminal of the transistor is connected to one end of the first resistor and one end of the second resistor respectively, the second terminal is connected to the input terminal of the transformer unit, and the third terminal is connected to ground;

[0040] The other end of the first resistor is connected to the pulse unit;

[0041] The other end of the second resistor is connected to ground.

[0042] In one embodiment, the circuit further includes a filtering module, comprising a filtering capacitor, one end of which is connected to one end of a Zener diode, and the other end serving as the output terminal of a constant voltage AC signal generating circuit for outputting an AC voltage signal.

[0043] The second technical problem mentioned above is solved by the following technical solution:

[0044] A combustion device includes a constant voltage AC signal generating circuit as described in any of the above embodiments. Attached Figure Description

[0045] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0046] Figure 1 This is a schematic diagram of the structure of a constant voltage AC signal generating circuit according to an embodiment of the present invention;

[0047] Figure 2 This is a circuit diagram of a voltage regulator module in a constant voltage AC signal generating circuit according to an embodiment of the present invention;

[0048] Figure 3 This is a circuit diagram of a specific embodiment of a constant voltage AC signal generating circuit according to this utility model;

[0049] Figure 4 This is a circuit diagram of a specific embodiment of a constant voltage AC signal generating circuit according to this utility model;

[0050] Figure 5 This is a circuit diagram of a specific embodiment of a constant voltage AC signal generating circuit according to this utility model;

[0051] Figure 6 This is a circuit diagram of a specific embodiment of a constant voltage AC signal generating circuit according to this utility model;

[0052] Figure 7 This is a circuit diagram of a specific embodiment of a constant voltage AC signal generating circuit according to this utility model;

[0053] Figure 8 This is a circuit diagram of a specific embodiment of a constant voltage AC signal generating circuit according to this utility model;

[0054] Figure 9 This is a circuit diagram of a specific embodiment of a constant voltage AC signal generating circuit according to this utility model;

[0055] Figure 10 This is a circuit diagram of a specific embodiment of a constant voltage AC signal generating circuit according to this utility model;

[0056] Figure 11 This is a circuit diagram of a flame ion detection circuit according to an embodiment of the present invention.

[0057] Explanation of reference numerals in the attached figures:

[0058] 11. Voltage conversion module; 111. Pulse unit; 112. Transformer unit; 113. Switching unit; 114. Rectifier unit; 115. Voltage divider unit; 12. Voltage regulator module. Detailed Implementation

[0059] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0060] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "multiple" means two or more.

[0061] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0062] Gas water heaters are widely used, and constant-voltage AC signals are involved in both the ignition circuit and flame ionization signal detection processes. However, in related technologies, constant-voltage AC signals typically employ open circuit structures, resulting in unstable peak voltages. This significantly impacts the accuracy and sensitivity of some signal detection during gas water heater operation, potentially affecting safety. For example, in flame ionization signal detection, due to component performance variations and the open circuit structure, different AC signal sources output voltage values ​​that fluctuate within a certain range. This makes precise detection of the flame ionization signal impossible, affecting its sensitivity and, in severe cases, potentially leading to safety issues due to delayed detection.

[0063] To address the aforementioned problems, this invention provides a constant voltage AC signal generating circuit, comprising: a voltage conversion module and a voltage regulator module; the voltage regulator module includes: a charging capacitor and a Zener diode; wherein, one end of the charging capacitor is connected to the output terminal of the voltage conversion module and the first end of the Zener diode, respectively, and the other end is connected to the voltage feedback terminal of the voltage conversion module and the second end of the Zener diode, respectively, and grounded; the first end of the Zener diode serves as the output terminal of the voltage regulator module, used to output an AC voltage signal. Thus, by providing feedback to the output AC voltage signal through the Zener diode, the voltage conversion module can control the voltage conversion based on the feedback received from the Zener diode at the voltage feedback terminal, forming a closed-loop control of the output AC voltage signal, ensuring a constant AC voltage signal.

[0064] The following is combined Figures 1 to 11 The following describes embodiments of the present invention.

[0065] According to an embodiment of the present invention, a constant voltage AC signal generating circuit is provided. Figure 1 This is a schematic diagram of a constant voltage AC signal generating circuit according to an embodiment of the present invention, as shown below. Figure 1 As shown, the constant voltage AC signal generating circuit includes a voltage conversion module 11 and a voltage regulator module 12. The voltage conversion module 11 performs voltage conversion to generate an AC voltage; the voltage regulator module 12 regulates the AC voltage generated by the voltage conversion module 11 to output an AC voltage signal.

[0066] Specifically, Figure 2 This is a circuit diagram of a voltage regulator module in a constant voltage AC signal generating circuit according to an embodiment of this utility model, as shown below. Figure 2As shown, the voltage regulator module 12 includes a charging capacitor C1 and a Zener diode Z1. One end of the charging capacitor C1 is connected to the output terminal of the voltage conversion module 11 and the first end of the Zener diode Z1, respectively. The other end of the charging capacitor C1 is connected to the voltage feedback terminal of the voltage conversion module 11 and the second end of the Zener diode Z1, and is grounded. Simultaneously, the first end of the Zener diode Z1 serves as the output terminal of the voltage regulator module 12, used to output an AC voltage signal. Therefore, the Zener diode Z1 is connected in parallel across the charging capacitor C1, and the voltage of the Zener diode Z1 is the voltage generated by the charging capacitor C1 during charging. Furthermore, the second end of the Zener diode Z1 is also connected to the voltage feedback terminal of the voltage conversion module 11, thus forming a closed-loop control of the output AC voltage signal. When the voltage across the charging capacitor C1 does not trigger the avalanche breakdown of the Zener diode Z1, no current signal is generated on the Zener diode Z1, and the voltage feedback terminal of the voltage conversion module 11 cannot receive the feedback signal; when the voltage across the charging capacitor C1 triggers the avalanche breakdown of the Zener diode Z1, a current signal is generated on the Zener diode Z1, the voltage feedback terminal of the voltage conversion module 11 receives the feedback signal, and thus controls the voltage conversion according to the feedback signal.

[0067] In one embodiment, the voltage conversion module 11 can be implemented based on boosting and inverting a low-voltage DC signal. Specifically, the voltage conversion module 11 includes: a pulse unit 111, a transformer unit 112, a switching unit 113, and a rectifier unit 114. The output terminal of the pulse unit 111 is connected to the first terminal of the switching unit 113; the input terminal of the transformer unit 112 is connected to the second terminal of the switching unit 113, and the output terminal of the transformer unit 112 is connected to one end of the rectifier unit 114; the other end of the rectifier unit 114 is connected to one end of the charging capacitor C1 and the first end of the Zener diode Z1, respectively; the third end of the switching unit 113 serves as the voltage feedback terminal of the voltage conversion module 11, and is connected to the other end of the charging capacitor C1 and the second end of the Zener diode Z1, and is grounded. In the voltage conversion module 11, the pulse unit 111 is used to output pulse signals to the switching unit 113. At the same time, the third terminal of the switching unit 113 serves as the voltage feedback terminal of the voltage conversion module 11, and is connected to the other end of the charging capacitor C1 and the second terminal of the Zener diode Z1, respectively. Thus, the feedback from the voltage regulator module 12 to the switching unit 113, in conjunction with the pulse unit 111, controls the switching unit 113 to turn on and off, thereby controlling whether the transformer unit 112 is working.

[0068] In one embodiment, the rectifier unit 114 can be a rectifier circuit of any structure, such as a full-bridge rectifier circuit, a half-bridge rectifier circuit, etc. In this embodiment, in order to simplify the circuit structure, the rectifier unit 114 adopts a rectifier diode D1. The positive terminal of the rectifier diode D1 is connected to the output terminal of the transformer unit 112, and the negative terminal is connected to one end of the charging capacitor C1 and the first end of the first resistor R1, respectively.

[0069] In one embodiment, Figure 3 and Figure 4 This is a circuit diagram of a specific embodiment of a constant voltage AC signal generating circuit according to this utility model, as shown below. Figure 3 and Figure 4 As shown, the transformer unit 112 includes a primary winding and a secondary winding of the transformer, and the pulse unit 111 includes a feedback winding of the transformer. One end of the feedback winding is connected to a power source, and the other end is connected to the first terminal of the switching unit 113; one end of the primary winding is connected to a power source, and the other end is connected to the second terminal of the switching unit 113; one end of the secondary winding is connected to one end of the rectifier unit 114, and the other end is grounded.

[0070] In this embodiment, the transformer unit 112 and the pulse unit 111 constitute a complete transformer. When the primary winding is connected to the power supply and energized, the secondary winding forms a boost voltage through coil coupling, thereby generating an AC signal. At this time, a voltage difference is generated across the feedback winding. When the voltage difference across the feedback winding reaches a certain value, the switch unit 113 is disconnected, thereby disconnecting the primary winding from ground and stopping the secondary winding from boosting voltage. At this time, there is no voltage difference across the feedback winding, and the switch unit 113 is reconnected, so that the primary winding is energized again and the secondary winding boosts voltage.

[0071] In one embodiment, such as Figure 3 and Figure 4 As shown, the switching unit 113 may include transistor Q. When there is no voltage difference across the feedback winding, transistor Q1 is turned on, energizing the primary winding and boosting the secondary winding voltage. When the voltage difference across the feedback winding reaches a certain value, transistor Q1 is turned off, disconnecting the primary winding from ground and stopping the secondary winding voltage boosting. When the Zener diode Z1 is not broken down, transistor Q1 is turned on, energizing the primary winding and boosting the secondary winding voltage. When the Zener diode Z1 breaks down, transistor Q1 is turned off, disconnecting the primary winding from ground and stopping the secondary winding voltage boosting.

[0072] In one embodiment, Figure 5 and Figure 6 This is a circuit diagram of a specific embodiment of a constant voltage AC signal generating circuit according to this utility model, as shown below. Figure 5 and Figure 6 As shown, the transformer unit 112 includes a primary winding and a secondary winding of a transformer, and the pulse unit 111 includes a pulse signal generator. The pulse signal generator is connected to the first terminal of the switching unit 113; one end of the primary winding is connected to a power supply, and the other end is connected to the second terminal of the switching unit 113; one end of the secondary winding is connected to one end of the rectifier unit 114, and the other end is grounded. Compared to... Figure 3 and Figure 4 In the embodiment shown, a pulse signal generator is used instead of the feedback winding of the transformer, thereby reducing the use of winding coils.

[0073] In one embodiment, such as Figure 5 and Figure 6 As shown, the switching unit 113 may include transistor Q1. When the pulse signal generator outputs a high-level signal, transistor Q1 is turned on, energizing the primary winding and boosting the secondary winding; when the pulse signal generator outputs a low-level signal, transistor Q1 is turned off, disconnecting the primary winding from ground and stopping the secondary winding from boosting. When the Zener diode Z1 is not broken down, transistor Q1 is turned on, energizing the primary winding and boosting the secondary winding; when the Zener diode Z1 breaks down, transistor Q1 is turned off, disconnecting the primary winding from ground and stopping the secondary winding from boosting.

[0074] In one embodiment, Figure 7 and Figure 8 This is a circuit diagram of a specific embodiment of a constant voltage AC signal generating circuit according to this utility model, as shown below. Figure 7 and Figure 8 As shown, the transformer unit 112 includes an I-shaped inductor L1, and the pulse unit 111 includes a pulse signal generator. The pulse signal generator is connected to the first terminal of the switching unit 113; one end of the I-shaped inductor L1 is connected to the power supply, and the other end is connected to one end of the charging capacitor C1, one end of the Zener diode Z1, and the second terminal of the switching unit 113, respectively. Compared to... Figure 5 and Figure 6 In the embodiment shown, an I-shaped inductor L1 is used to replace the primary and secondary windings of the transformer, thereby further reducing the use of winding coils.

[0075] In one embodiment, such as Figure 7 and Figure 8 As shown, the switching unit 113 may include transistor Q1. When the pulse signal generator outputs a high-level signal, transistor Q1 is turned on, connecting the I-inductor L1 to ground, enabling normal voltage boosting; when the pulse signal generator outputs a low-level signal, transistor Q1 is turned off, disconnecting the I-inductor L1 from ground and stopping voltage boosting. When the Zener diode Z1 is not broken down, transistor Q1 is turned on, connecting the I-inductor L1 to ground, enabling normal voltage boosting; when the Zener diode Z1 breaks down, transistor Q1 is turned off, disconnecting the I-inductor L1 from ground and stopping voltage boosting.

[0076] In the above embodiments, the waveform generated by the pulse generator is a square wave waveform; at the same time, the pulse signal generator can also be replaced by any circuit structure that can generate pulse signals, such as a microcontroller, a 555 chip, an inverter, or an amplifier.

[0077] In one embodiment, the voltage conversion module 11 can be implemented based on the step-down and inversion of a low-voltage DC signal. Specifically, the voltage conversion module 11 includes: a voltage divider unit 115, a transformer unit 112, and a switching unit 113. Figure 9 and Figure 10 This is a circuit diagram of a specific embodiment of a constant voltage AC signal generating circuit according to this utility model, as shown below. Figure 9 and Figure 10 As shown, the transformer unit 112 includes an I-shaped inductor L1, and the voltage divider unit 115 includes a first voltage divider resistor R3, a second voltage divider resistor R4, a current limiting resistor R5, and a second diode D2.

[0078] In this circuit, one end of the first voltage divider resistor R3 is connected to a power supply, which is a high-voltage DC power supply, and the other end is connected to the second terminal of the switching unit 113 and one end of the second voltage divider resistor R4, respectively. The other end of the second voltage divider resistor R3 is connected to one end of the current-limiting resistor R5 and one end of the second diode D2, respectively. The first voltage divider resistor R3 serves as a current-limiting resistor and a load resistor for the high-voltage DC power supply when it is turned on. On the other hand, it forms a series voltage divider circuit with the second voltage divider resistor R4 and the second diode D2.

[0079] The other end of the current-limiting resistor R5 is connected to the first end of the switching unit 113, serving to protect the switching unit 113. The voltage passing through the second diode D2 in the forward direction reaches the switching unit 113 through the current-limiting resistor R5, thereby turning on the switching unit 113. The other end of the second diode D2 is connected to the other end of the charging capacitor C1 and the second end of the Zener diode Z1, and is grounded. One end of the I-shaped inductor L1 is connected to the third end of the switching unit, and the other end is connected to one end of the charging capacitor C1 and the first end of the Zener diode Z1, respectively.

[0080] In one embodiment, such as Figure 9 and Figure 10 As shown, the switching unit 113 may include transistor Q1. When the voltage reaches transistor Q1 through the current-limiting resistor R5, transistor Q1 conducts, connecting the I-inductor L1 to the power supply, enabling normal voltage boosting. During the voltage boosting process of the I-inductor L1, the voltage at the third terminal of transistor Q1 gradually increases. When the voltage at the third terminal of transistor Q1 is greater than the voltage at the first terminal, transistor Q1 is turned off, disconnecting the I-inductor L1 from the power supply and stopping voltage boosting. When the Zener diode Z1 is not broken down, transistor Q1 conducts, connecting the I-inductor L1 to the power supply, enabling normal voltage boosting; when the Zener diode Z1 breaks down, transistor Q1 is turned off, disconnecting the I-inductor L1 from the power supply and stopping voltage boosting.

[0081] In one embodiment, the type of transistor Q1 is not limited. The first terminal of transistor Q1 is the first terminal of switching unit 113, the second terminal of transistor Q1 is the second terminal of switching unit 113, and the third terminal of transistor Q1 is the third terminal of switching unit 113.

[0082] In one embodiment, such as Figure 3 , Figure 5 and Figure 7 As shown, to protect transistor Q1 in the switching unit 113, the switching unit 113 includes a first resistor R1 and a second capacitor C2 in addition to transistor Q1. In this case, transistor Q1 is a current-type device. The first terminal of transistor Q1 is connected to one end of the first resistor R1 and one end of the second capacitor C2, respectively; the second terminal is connected to the input terminal of the transformer unit 112; and the third terminal is grounded. The other end of the first resistor R1 is connected to the pulse unit 111; and the other end of the second capacitor C2 is grounded.

[0083] In one embodiment, such as Figure 4 , Figure 6 and Figure 8 As shown, to protect transistor Q1 in the switching unit 113, the switching unit 113 includes a first resistor R1 and a second resistor R2 in addition to transistor Q1. In this case, transistor Q1 is a voltage-type device. The first terminal of transistor Q1 is connected to one end of the first resistor R1 and one end of the second resistor R2, respectively. The second terminal is connected to the input terminal of the transformer unit 112, and the third terminal is grounded. The other end of the first resistor R1 is connected to the pulse unit 111, and the other end of the second resistor R2 is grounded.

[0084] In one embodiment, the circuit further includes a filtering module. The filtering module includes a filtering capacitor C3, which is used to filter the AC voltage signal output by the voltage regulator module 12. One end of the filtering capacitor C3 is connected to one end of the Zener diode Z1, and the other end serves as the output terminal of the constant voltage AC signal generator circuit, used to output an AC voltage signal.

[0085] The constant voltage AC signal generating circuit provided by this utility model sets a Zener diode in the voltage regulator module, and sets the first end of the Zener diode to one end of the charging capacitor and the output terminal of the voltage output module respectively, and the second end to the other end of the charging capacitor and the voltage feedback terminal of the voltage conversion module respectively. In this way, the Zener diode provides feedback on the output AC voltage signal, so that the voltage conversion module can control the voltage conversion according to the feedback of the Zener diode received by the voltage feedback terminal, forming a closed-loop control of the output AC voltage signal and ensuring that the AC voltage signal is constant.

[0086] According to an embodiment of the present invention, another aspect provides a combustion device, including a constant voltage AC signal generating circuit as described in any of the above embodiments. The constant voltage AC signal generating circuit can be used to provide a stable AC voltage signal to any circuit or structure in the combustion device that requires an AC voltage signal, such as an ignition circuit or a flame ionization detection circuit.

[0087] In one embodiment, the combustion device includes at least a constant voltage AC signal generating circuit as described in any of the above embodiments, and a flame ionization detection circuit; wherein the constant voltage AC signal generating circuit is used to provide a constant AC voltage signal to the flame ionization detection circuit, and the flame ionization detection circuit is used to detect the flame ionization signal to determine the combustion state of the flame in the combustion device.

[0088] In one embodiment, Figure 11 This is a circuit diagram of a flame ionization detection circuit according to an embodiment of the present invention, as shown below. Figure 11 As shown, the flame ion detection circuit includes: a third voltage divider resistor R6, a front-end resistor R7, an input resistor R8, a feedback resistor R9, an amplifier, and a processor.

[0089] Among them, one end of the third voltage divider resistor R6 is connected to the flame detection electrode S3, and the other end is connected to the constant voltage AC signal generating circuit and one end of the front-end resistor R7 respectively. The other end of the front-end resistor R7 is connected to one end of the input resistor R8. The third voltage divider resistor R6 is used to protect the flame detection electrode S3 and prevent the voltage input to the constant voltage AC signal generating circuit from exceeding the voltage range that the flame detection electrode S3 can withstand.

[0090] The input resistor R8 is connected to the first terminal of the amplifier and one terminal of the feedback resistor R9, respectively. The other terminal of the feedback resistor R9 is connected to the third terminal of the amplifier. The second terminal of the amplifier is grounded, and the third terminal is connected to the processor. The first terminal of the amplifier corresponds to the negative input terminal, the second terminal corresponds to the positive input terminal, and the third terminal corresponds to the output terminal. This forms an inverting amplifier that amplifies the flame ion signal detected by the flame detection electrode S3, enabling the processor to perform refined detection of the flame ion signal.

[0091] In one embodiment, the flame signal sensing circuit further includes a fourth capacitor C4, which is used for pre-processing and filtering of the flame ionization signal input to the amplifier. One end of the fourth capacitor C4 is connected to the other end of the front-end resistor R7 and one end of the input resistor R8, respectively, and the other end is connected to ground.

[0092] In one embodiment, the flame signal sensing circuit further includes a first clamping diode D3 and a second clamping diode D4. One end of the first clamping diode D3 is connected to the power supply, and the other end is connected to the other end of the front-end resistor R7, one end of the input resistor R8, and one end of the second clamping diode D4, respectively. The other end of the second clamping diode D4 is connected to ground, thereby forming a clamp to ground and to VCC.

[0093] In one embodiment, the flame signal sensing circuit further includes a tenth resistor R10 and a fifth capacitor C5. The tenth resistor R10 and the fifth capacitor C5 constitute an RC filter circuit, which is used to filter the amplified flame ion signal to improve the accuracy of the amplified flame ion signal. One end of the tenth resistor R10 is connected to the third terminal of the amplifier, and the other end is connected to the processor and one end of the fifth capacitor C5, respectively; the other end of the fifth capacitor C5 is grounded.

[0094] In the specific implementation of the above embodiments, the technical features can be combined in any non-contradictory way. For the sake of brevity, not all possible combinations of the above technical features are described. However, as long as the combination of these technical features is not contradictory, it should be considered to be within the scope of this specification.

[0095] The specific embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are detailed, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these modifications and improvements all fall within the protection scope of this utility model.

Claims

1. A constant-voltage AC signal generating circuit characterized by comprising: The voltage conversion module (11) and the voltage stabilizing module (12) are included. The voltage stabilizing module (12) includes a charging capacitor and a voltage stabilizing tube. One end of the charging capacitor is connected with the output end of the voltage conversion module (11) and the first end of the voltage stabilizing tube respectively, the other end is connected with the voltage feedback end of the voltage conversion module (11) and the second end of the voltage stabilizing tube respectively, and is grounded. The first end of the voltage stabilizing tube is used as the output end (S1) of the voltage stabilizing module (12) for outputting an alternating voltage signal. The voltage conversion module (11) includes a pulse unit (111), a voltage transformation unit (112), a switch unit (113) and a rectification unit (114).

2. The circuit of claim 1, wherein, The output end of the pulse unit (111) is connected with the first end of the switch unit (113). The input end of the voltage transformation unit (112) is connected with the second end of the switch unit (113), and the output end of the voltage transformation unit (112) is connected with one end of the rectification unit (114). The other end of the rectification unit (114) is connected with one end of the charging capacitor and the first end of the voltage stabilizing tube respectively. The third end of the switch unit (113) is used as the voltage feedback end of the voltage conversion module (11), and is connected with the other end of the charging capacitor and the second end of the voltage stabilizing tube respectively, and is grounded. The voltage transformation unit (112) includes a primary winding and a secondary winding of a transformer, and the pulse unit (111) includes a feedback winding of the transformer.

3. The circuit of claim 2, wherein, One end of the feedback winding is connected with a power supply, and the other end is connected with the first end of the switch unit (113). One end of the primary winding is connected with a power supply, and the other end is connected with the second end of the switch unit (113). One end of the secondary winding is connected with one end of the rectification unit (114), and the other end is grounded. The voltage transformation unit (112) includes a primary winding and a secondary winding of a transformer, and the pulse unit (111) includes a pulse signal generator.

4. The circuit of claim 2, wherein, The pulse signal generator is connected with the first end of the switch unit (113). One end of the primary winding is connected with a power supply, and the other end is connected with the second end of the switch unit (113). One end of the secondary winding is connected with one end of the rectification unit (114), and the other end is grounded. The voltage transformation unit (112) includes an I-shaped inductor, and the pulse unit (111) includes a pulse signal generator.

5. The circuit of claim 2, wherein, The pulse signal generator is connected with the first end of the switch unit (113). One end of the I-shaped inductor is connected with a power supply, and the other end is connected with one end of the charging capacitor, one end of the voltage stabilizing tube and the second end of the switch unit (113) respectively. The voltage conversion module (11) includes a voltage division unit (115), a voltage transformation unit (112) and a switch unit (113).

6. The circuit of claim 1, wherein, The voltage transformation unit (112) includes an I-shaped inductor, and the voltage division unit (115) includes a first voltage division resistor and a second voltage division resistor, a current limiting resistor and a second diode. ​ One end of the first voltage division resistor is connected to a power supply, and the other end is connected to the second end of the switch unit (113) and one end of the second voltage division resistor, respectively; The other end of the second voltage division resistor is connected to one end of the current limiting resistor and one end of the second diode, respectively; The other end of the current limiting resistor is connected to the first end of the switch unit (113); The other end of the second diode is connected to the other end of the charging capacitor and the second end of the voltage stabilizing tube, and is grounded; One end of the I-shaped inductor is connected to the third end of the switch unit (113), and the other end is connected to one end of the charging capacitor and the first end of the voltage stabilizing tube, respectively.

7. The circuit of any one of claims 2-5, wherein, The switch unit (113) comprises a transistor, a first resistor and a second capacitor; Wherein, the transistor is a current type device; the first end of the transistor is connected to one end of the first resistor and one end of the second capacitor, respectively, the second end is connected to the input end of the voltage conversion unit (112), and the third end is grounded; The other end of the first resistor is connected to the pulse unit (111); The other end of the second capacitor is grounded.

8. The circuit of any one of claims 2-5, wherein, The switch unit (113) comprises a transistor, a first resistor and a second resistor; Wherein, the transistor is a voltage type device; the first end of the transistor is connected to one end of the first resistor and one end of the second resistor, respectively, the second end is connected to the input end of the voltage conversion unit (112), and the third end is grounded; The other end of the first resistor is connected to the pulse unit (111); The other end of the second resistor is grounded.

9. The circuit of claim 1, wherein, The circuit further comprises a filtering module comprising a filtering capacitor, one end of which is connected to one end of the voltage stabilizing tube, and the other end is the output end (S2) of the constant voltage alternating current signal generating circuit, used for outputting the alternating voltage signal.

10. A combustion apparatus characterized by comprising: The constant voltage alternating current signal generating circuit comprises the constant voltage alternating current signal generating circuit according to any one of claims 1-9. The constant voltage alternating current signal generating circuit comprises the constant voltage alternating current signal generating circuit according to any one of claims 1-9.

Images