Frequency converter and cooking equipment

Abstract

The utility model provides a frequency converter and cooking equipment, and the frequency converter comprises a communication interface which is suitable for being connected with a computer board and a gear resistor; the communication circuit is connected with the communication interface; the control chip is connected with the communication circuit and is used for determining a target device connected with the communication interface according to a signal transmitted by the communication circuit; and under the condition that the target device is the computer board, adjusting the output power of the power switch based on a pulse width modulation signal sent by the computer board, and when the target device is the gear resistor, adjusting the output power of the power switch based on the voltage corresponding to the gear resistor.

Description

Technical Field

[0001] The utility model relates to the technical field of frequency converters, in particular to a frequency converter and a cooking device. Background Art

[0002] Microwave ovens are divided into transformer microwave ovens and variable frequency microwave ovens according to power devices. At the same time, they are divided into mechanical microwave ovens and electronic microwave ovens according to whether there is a computer board or not.

[0003] For electronic microwave ovens, the computer board installed therein can send out a pulse width modulation signal. The frequency converter is connected to the computer board via a communication interface to receive the pulse width modulation signal. At this time, the frequency converter can control the switching device based on the pulse width modulation signal to achieve power output.

[0004] At present, frequency converters can only be applied to electronic microwave ovens but not mechanical microwave ovens. As a result, when producing mechanical and electronic microwave ovens, in addition to producing frequency converters suitable for electronic microwave ovens, transformers suitable for mechanical microwave ovens must also be produced, which increases the complexity of production management. Utility Model Content

[0005] The utility model aims to solve at least one of the technical problems existing in the prior art or related technology.

[0006] To this end, a first aspect of the present invention is to provide a frequency converter.

[0007] A second aspect of the present invention is to provide a cooking device.

[0008] In view of this, according to the first aspect of the utility model, the utility model provides a frequency converter for a cooking device, the cooking device comprising a power switch, the frequency converter comprising: a communication interface, the communication interface being suitable for being connected to a computer board and a gear resistor; a communication circuit connected to the communication interface; a control chip connected to the communication circuit, for determining a target device connected to the communication interface according to a signal transmitted by the communication circuit; and in a case where the target device is a computer board, adjusting the output power of the power switch based on a pulse width modulation signal sent by the computer board; in a case where the target device is a gear resistor, adjusting the output power of the power switch based on a voltage corresponding to the gear resistor.

[0009] The utility model proposes a frequency converter. Specifically, the computer board belongs to an electronic microwave oven, and the gear resistor belongs to a mechanical microwave oven. In the frequency converter proposed in the utility model, it can not only be connected to the computer board, but also be connected to the gear resistor, and the control chip can know the target device connected to the communication interface according to the signal transmitted by the communication circuit, and then select the way to control the power switch according to the target device connected to the communication interface, so as to achieve output power adjustment.

[0010] In the above technical solution, the proposed inverter can be adapted to electronic microwave ovens to achieve output power adjustment, and can also be adapted to mechanical microwave ovens to achieve output power adjustment. Obviously, the same inverter can be used for mechanical microwave ovens and electronic microwave ovens, and there is no need to produce power supplies corresponding to mechanical microwave ovens and electronic microwave ovens. Therefore, the complexity of production management is simplified.

[0011] From the perspective of standardized management, if both inverters for electronic microwave ovens and transformers for mechanical microwave ovens are produced at the same time, corresponding codes need to be assigned to the two power sources, the inverters and the transformers. This requires a lot of manpower, material and financial resources to manage these codes, increasing the company's management costs. At the same time, if there are too many codes for similar products, it is easy to cause confusion among the codes, and employees will not be able to accurately identify the products, which may cause losses to the company. In addition, because multiple codes for similar products require more inventory space, it also increases the company's inventory costs.

[0012] For mechanical microwave ovens, since they do not have a computer board, they cannot achieve power adjustment. Therefore, mechanical microwave ovens have the following disadvantages:

[0013] 1. Uneven heating of food: Since mechanical microwave ovens cannot adjust power, food is prone to partial overheating or overcooling during the heating process, resulting in uneven heating of food. This type of problem will affect the taste and quality of the food.

[0014] 2. Inaccurate heating time: Since mechanical microwave ovens can only be controlled by heating time, they cannot be fine-tuned according to the size and type of ingredients. The heating time is set manually by the user and cannot be accurate to the minute or second, resulting in inaccurate heating time.

[0015] 3. High energy consumption: The heating power of a mechanical microwave oven will remain unchanged after the user selects the heating power and cannot be adjusted. Therefore, the energy consumption of a mechanical microwave oven is relatively high, which is not conducive to environmental protection.

[0016] 4. Not suitable for diverse cooking needs: Mechanical microwave ovens can only perform basic heating and defrosting functions, which cannot meet people’s diverse cooking needs, limiting their scope of use.

[0017] When the frequency converter proposed in the utility model is applied to a mechanical microwave oven, it can enable the mechanical microwave oven to achieve adjustable output power. When the output power is adjustable, the problems of uneven heating of food and high energy consumption can be improved. At the same time, the frequency converter can be used to achieve refined control and improve the problem of inaccurate heating time.

[0018] In addition, users can use the inverter to control the power switch to work in different working modes, thereby realizing different cooking functions to meet different cooking needs and achieve diverse cooking effects.

[0019] In addition, the frequency converter proposed by the utility model also has the following additional technical features.

[0020] In some technical schemes, optionally, the communication interface includes a first sub-interface and a second sub-interface, the first sub-interface is suitable for connecting to a computer board, and the second sub-interface is suitable for connecting to a gear resistor; the communication circuit includes: a first communication circuit, the input end of the first communication circuit is connected to the first sub-interface, and the output end of the first communication circuit is connected to the signal input end of the control chip; a second communication circuit, the input end of the second communication circuit is connected to the second sub-interface, and the output end of the second communication circuit is connected to the voltage input end of the control chip; wherein, when the first sub-interface is connected to the computer board, the output end of the first communication circuit outputs a pulse width modulation signal, and when the second sub-interface is connected to the gear resistor, the output end of the second communication circuit outputs the voltage corresponding to the gear resistor.

[0021] In this technical solution, the communication interface includes a first sub-interface and a second sub-interface. The first sub-interface is used to connect to the computer, and the second sub-interface is used to connect to the gear resistor. In this process, the frequency converter can be adapted to the computer without changing the computer board. At the same time, it is also convenient to connect the gear resistor to the communication interface.

[0022] In the above technical scheme, the communication circuit is divided into a first communication circuit and a second communication circuit so as to separate the first sub-interface and the control chip and the second sub-interface and the control chip from each other, thereby reducing mutual interference between the two, causing the control chip to make misjudgments in the process of determining the target device, thereby affecting the accurate operation of the cooking equipment.

[0023] In some technical solutions, the first sub-interface and the second sub-interface are integrated together.

[0024] In this technical solution, the first sub-interface and the second sub-interface are integrated to reduce the number of interfaces, thereby reducing the probability of misconnection during the assembly process, thereby improving assembly efficiency.

[0025] In some technical schemes, the signal input terminal and the voltage input terminal are two interfaces of the control chip, which are respectively connected to the first communication circuit and the second communication circuit. If the control chip receives a pulse width modulation signal, it is considered that the cooking device on which the inverter is installed is an electronic microwave oven. If the voltage corresponding to the gear resistance is received, it is considered that the cooking device on which the inverter is installed is a mechanical microwave oven.

[0026] Exemplarily, when the voltage transmitted by the second communication circuit is the first voltage, it is considered that the second sub-interface is not connected to the gear resistor. Conversely, if the voltage transmitted by the second communication circuit is less than the first voltage, it is considered that the second sub-interface is connected to the gear resistor, that is, the cooking device on which the inverter is installed is considered to be a mechanical microwave oven.

[0027] For example, when the first voltage is 5 volts, when the voltage transmitted by the second communication circuit is 5 volts, it is considered that the second sub-interface is not connected to the gear resistor. If the voltage transmitted by the second communication circuit is less than 5 volts, it is considered that the second sub-interface is connected to the gear resistor, that is, the cooking equipment on which the inverter is installed is considered to be a mechanical microwave oven.

[0028] In some technical schemes, optionally, the first sub-interface includes a first terminal pin and a second terminal pin, the first terminal pin is used to receive a pulse width modulation signal, and the second terminal pin is used to connect to a reference ground, and the first communication circuit includes: a first resistor, a first end of the first resistor is connected to the first terminal pin; a second resistor, a first end of the second resistor is connected to the second terminal pin, and a second end of the second resistor is connected to the second end of the first resistor; an optocoupler, a first end of the optocoupler is connected to the first end of the second resistor, and a second end of the optocoupler is connected to the second end of the second resistor, a third end of the optocoupler is used to be connected to a signal input end of a control chip, and a fourth end of the optocoupler is used to access a first power supply; a third resistor, a first end of the third resistor is connected to the third end of the optocoupler, and a second end of the third resistor is grounded.

[0029] In this technical solution, the first end pin can be connected to the computer board to receive the pulse width modulation signal from the computer board. By setting the second end pin, the second end pin can be used as a reference to confirm the voltage size of the pulse width modulation signal.

[0030] Among them, after the first resistor and the second resistor are connected together, they are connected in series between the first end pin and the second end pin. Therefore, as the voltage of the pulse width modulation signal changes, the voltage across the second resistor also changes, so that the light-emitting diodes set at the first end of the optocoupler and the second end of the optocoupler emit light, and correspondingly, the photosensitive diodes set at the third end of the optocoupler and the fourth end of the optocoupler receive the light emitted by the light-emitting diode and are turned on, thereby outputting a corresponding voltage signal based on the third end of the optocoupler. The above voltage signal can be reflected at the first end of the third resistor, thereby realizing the transmission of the pulse width modulation signal.

[0031] In this technical solution, the use of optocouplers can isolate the computer board from the control chip, thereby reducing the probability of damage to the control chip due to voltage shock while realizing the transmission of pulse width modulation signals, thereby improving the safety of the inverter.

[0032] In some technical solutions, optionally, the first communication circuit further includes: a first capacitor, a first end of the first capacitor is connected to the third end of the optocoupler, and a second end of the first capacitor is grounded.

[0033] In this technical solution, the first capacitor is provided so as to utilize the first capacitor to filter the signal interference outputted from the third terminal of the optical coupler, thereby ensuring the accuracy of the pulse width modulation signal.

[0034] In some technical solutions, the value of the first capacitor can be determined according to actual usage requirements, which will not be elaborated here.

[0035] In some technical solutions, optionally, the first communication circuit further includes: a fourth resistor, and the fourth resistor is located between the third end of the optocoupler and the signal input end of the control chip.

[0036] In this technical solution, since the signal output by the third terminal of the optocoupler directly acts on the signal input terminal of the control chip, when the current of the signal is relatively large, it is easy to cause overcurrent in the control chip, thereby causing the control chip to overcurrent and burn out.

[0037] By setting the fourth resistor, the current flowing through the control chip can be limited by the fourth resistor, thereby reducing the probability of the control chip being damaged due to overcurrent, thereby improving the safety of the inverter.

[0038] In some technical solutions, optionally, the first sub-interface also includes a third terminal pin, and the first communication circuit also includes: a fifth resistor, the first end of the fifth resistor is connected to the second terminal pin, and the second end of the fifth resistor is connected to the third terminal pin; wherein the voltage doubling circuit connected to the magnetron is connected to the reference ground through the fifth resistor.

[0039] In this technical solution, the fifth resistor and the third terminal pin are provided so that the current value flowing through the fifth resistor can be transmitted by using the first communication circuit, thereby realizing the detection of current anomaly.

[0040] Specifically, the current value flowing through the fifth resistor can be used to characterize the anode current of the magnetron, and then when the current value flowing through the fifth resistor exceeds the current threshold, protective measures are triggered, such as automatically cutting off the power supply of the cooking device or issuing an alarm signal, to prevent the magnetron from being damaged by overload or overheating, thereby ensuring the stability, reliability and performance of the inverter.

[0041] In addition, the magnetron anode current detection circuit can also be used for power control and regulation of the inverter to meet different working requirements of the electronic microwave oven.

[0042] In some technical solutions, optionally, the first communication circuit further includes: a sixth resistor, located between the first end and the second end of the fifth resistor.

[0043] In this technical solution, a sixth resistor is provided to limit the current flowing through the third terminal pin, thereby ensuring detection of the current value flowing through the fifth resistor while reducing the reliability of the circuit connected to the third terminal pin.

[0044] In some technical solutions, optionally, the second sub-interface includes a fourth pin and a fifth pin, the fourth pin is used to connect to the gear resistor, and the fifth pin is used to connect to the reference ground, and the second communication circuit includes: a seventh resistor, the first end of the seventh resistor is used to connect to the second power supply, and the second end of the seventh resistor is connected to the fourth pin and the voltage input terminal of the control chip.

[0045] In this technical solution, when the fourth end pin is connected to the gear resistor, the gear resistor and the seventh resistor will form a series relationship, and when the second power supply provides a voltage, a voltage division will be formed on the gear resistor. When the resistance of the gear resistor is different, the voltage presented by the second end of the seventh resistor is also different, so the detection of whether the second sub-interface is connected to the gear resistor can be realized based on the voltage at the fourth end pin.

[0046] Specifically, when the fourth end pin is not connected to the gear resistor, the voltage at the second end of the seventh resistor is the same as the voltage provided by the second power supply, and when the fourth end pin is connected to the gear resistor, the voltage at the second end of the seventh resistor changes with the resistance of the gear resistor.

[0047] Exemplarily, the voltage provided by the second power supply is 5 volts. When the fourth end pin is not connected to the gear resistor, the voltage at the second end of the seventh resistor is 5 volts. When the fourth end pin is connected to the gear resistor, the voltage at the second end of the seventh resistor is less than 5 volts.

[0048] In some technical solutions, optionally, the second communication circuit further includes: a second capacitor, a first end of the second capacitor is connected to the fifth terminal pin, and a second end of the second capacitor is connected to the voltage input terminal of the control chip.

[0049] In this technical solution, a second capacitor is provided so as to utilize the second capacitor to filter out voltage interference connected to the fourth terminal pin, thereby improving the accuracy of determining whether the second sub-interface is connected to the gear resistor.

[0050] In some technical solutions, optionally, the second communication circuit further includes: an eighth resistor, located between the second end of the seventh resistor and the voltage input end of the control chip.

[0051] In this technical solution, an eighth resistor is provided so as to utilize the eighth resistor to limit the current flowing through the voltage input terminal, thereby protecting the control chip and reducing the probability of damage to the control chip due to overcurrent.

[0052] According to a second aspect of the utility model, the utility model provides a cooking device, comprising: a frequency converter as described in any one of the above items.

[0053] In some technical solutions, optionally, the cooking device includes an electronic microwave oven or a mechanical microwave oven.

[0054] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0056] Figure 1 One of the connection diagrams of the frequency converter in the embodiment of the utility model is shown;

[0057] Figure 2 The second connection diagram of the frequency converter in the embodiment of the utility model is shown;

[0058] Figure 3 A schematic diagram of a control flow of a cooking device in a related technical solution is shown;

[0059] Figure 4 A control flow diagram of a cooking device in an embodiment of the utility model is shown.

[0060] in, Figure 1 and Figure 2 The corresponding relationship between the reference numerals and the component names is as follows:

[0061] 102 communication interface, 1022 first sub-interface, 1024 second sub-interface, 104 communication circuit, 1042 first communication circuit, 1044 second communication circuit, 106 control chip, 108 voltage doubling circuit, 110 power switch, 200 computer board, RL gear resistor, R1 first resistor, R2 second resistor, R3 third resistor, R4 fourth resistor, R5 fifth resistor, R6 sixth resistor, R7 seventh resistor, R8 eighth resistor, R9 ninth resistor, C1 first capacitor, C2 second capacitor, VCC1 first power supply, VCC2 second power supply, P signal input terminal, POWER voltage input terminal, A first terminal pin, B second terminal pin, C third terminal pin, D fourth terminal pin, F fifth terminal pin, GND grounding, EARTH grounding point, U optical coupler. DETAILED DESCRIPTION

[0062] In order to more clearly understand the above aspects, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0063] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0064] In one embodiment of the present invention, Figure 1 and Figure 2 As shown, a frequency converter is provided for a cooking device, the cooking device includes a power switch 110, and the frequency converter includes: a communication interface 102, the communication interface 102 is suitable for connecting to a computer board 200 and a gear resistor RL; a communication circuit 104, connected to the communication interface 102; a control chip 106, connected to the communication circuit 104, for determining the target device connected to the communication interface 102 according to the signal transmitted by the communication circuit 104; and when the target device is the computer board 200, adjusting the output power of the power switch 110 based on the pulse width modulation signal sent by the computer board 200; when the target device is the gear resistor RL, adjusting the output power of the power switch 110 based on the voltage corresponding to the gear resistor RL.

[0065] The utility model proposes a frequency converter. Specifically, the computer board 200 belongs to an electronic microwave oven, and the gear resistor RL belongs to a mechanical microwave oven. In the frequency converter proposed in the utility model, it can not only be connected to the computer board 200, but also be connected to the gear resistor RL, and the control chip 106 can know the target device connected to the communication interface 102 according to the signal transmitted by the communication circuit 104, and then select the way to control the power switch 110 according to the target device connected to the communication interface 102, so as to achieve output power adjustment.

[0066] In the above embodiment, the proposed inverter can be adapted to electronic microwave ovens to achieve output power adjustment, and can also be adapted to mechanical microwave ovens to achieve output power adjustment. Obviously, the same inverter can be used for mechanical microwave ovens and electronic microwave ovens, and there is no need to produce power supplies corresponding to mechanical microwave ovens and electronic microwave ovens. Therefore, the complexity of production management is simplified.

[0067] From the perspective of standardized management, if both inverters for electronic microwave ovens and transformers for mechanical microwave ovens are produced at the same time, corresponding codes need to be assigned to the two power sources, the inverters and the transformers. This requires a lot of manpower, material and financial resources to manage these codes, increasing the company's management costs. At the same time, if there are too many codes for similar products, it is easy to cause confusion among the codes, and employees will not be able to accurately identify the products, which may cause losses to the company. In addition, because multiple codes for similar products require more inventory space, it also increases the company's inventory costs.

[0068] For a mechanical microwave oven, since it does not have a computer board 200, it is impossible to achieve power adjustment. Therefore, the mechanical microwave oven has the following disadvantages:

[0069] 1. Uneven heating of food: Since mechanical microwave ovens cannot adjust power, food is prone to partial overheating or overcooling during the heating process, resulting in uneven heating of food. This type of problem will affect the taste and quality of the food.

[0070] 2. Inaccurate heating time: Since mechanical microwave ovens can only be controlled by heating time, they cannot be fine-tuned according to the size and type of ingredients. The heating time is set manually by the user and cannot be accurate to the minute or second, resulting in inaccurate heating time.

[0071] 3. High energy consumption: The heating power of a mechanical microwave oven will remain unchanged after the user selects the heating power and cannot be adjusted. Therefore, the energy consumption of a mechanical microwave oven is relatively high, which is not conducive to environmental protection.

[0072] 4. Not suitable for diverse cooking needs: Mechanical microwave ovens can only perform basic heating and defrosting functions, which cannot meet people’s diverse cooking needs, limiting their scope of use.

[0073] When the frequency converter proposed in the utility model is applied to a mechanical microwave oven, it can enable the mechanical microwave oven to achieve adjustable output power. When the output power is adjustable, the problems of uneven heating of food and high energy consumption can be improved. At the same time, the frequency converter can be used to achieve refined control and improve the problem of inaccurate heating time.

[0074] In addition, the user can use the inverter to control the power switch 110 to work in different working modes, thereby realizing different cooking functions, so as to meet different cooking needs and achieve diversified cooking effects.

[0075] In some embodiments, optionally, the gear resistor RL can be a mechanical switch or a mechanical knob, wherein the mechanical switch or the mechanical knob is used to modulate the heating power.

[0076] In some embodiments, optionally, the communication interface 102 includes a first sub-interface 1022 and a second sub-interface 1024, the first sub-interface 1022 is suitable for connecting to the computer board 200, and the second sub-interface 1024 is suitable for connecting to the gear resistor RL; the communication circuit 104 includes: a first communication circuit 1042, the input end of the first communication circuit 1042 is connected to the first sub-interface 1022, and the output end of the first communication circuit 1042 is connected to the signal input end P of the control chip 106; a second communication circuit 1044, the input end of the second communication circuit 1044 is connected to the second sub-interface 1024, and the output end of the second communication circuit 1044 is connected to the voltage input end POWER of the control chip 106; wherein, when the first sub-interface 1022 is connected to the computer board 200, the output end of the first communication circuit 1042 outputs a pulse width modulation signal, and when the second sub-interface 1024 is connected to the gear resistor RL, the output end of the second communication circuit 1044 outputs the voltage corresponding to the gear resistor RL.

[0077] In this embodiment, the communication interface 102 includes a first sub-interface 1022 and a second sub-interface 1024. The first sub-interface 1022 is used to connect to the computer, and the second sub-interface 1024 is used to connect to the gear resistor RL. In this process, the frequency converter can be adapted to the computer board 200 without changing it. At the same time, it is also convenient to connect the gear resistor RL to the communication interface 102.

[0078] In the above embodiment, the communication circuit 104 is divided into a first communication circuit 1042 and a second communication circuit 1044 so as to separate the first sub-interface 1022 and the control chip 106 and the second sub-interface 1024 and the control chip 106 from each other, thereby reducing mutual interference between the two, causing the control chip 106 to make misjudgments in the process of determining the target device, thereby affecting the accurate operation of the cooking device.

[0079] In some embodiments, the first sub-interface 1022 and the second sub-interface 1024 are integrated together.

[0080] In this embodiment, the first sub-interface 1022 and the second sub-interface 1024 are integrated to reduce the number of interfaces, thereby reducing the probability of misconnection during the assembly process, thereby improving assembly efficiency.

[0081] In some embodiments, the signal input terminal P and the voltage input terminal POWER are two interfaces of the control chip 106, which are respectively connected to the first communication circuit 1042 and the second communication circuit 1044. If the control chip 106 receives a pulse width modulation signal, it is considered that the cooking device on which the inverter is installed is an electronic microwave oven. If the voltage corresponding to the gear resistor RL is received, it is considered that the cooking device on which the inverter is installed is a mechanical microwave oven.

[0082] Exemplarily, when the voltage transmitted by the second communication circuit 1044 is the first voltage, it is considered that the second sub-interface 1024 is not connected to the gear resistor RL. Conversely, if the voltage transmitted by the second communication circuit 1044 is less than the first voltage, it is considered that the second sub-interface 1024 is connected to the gear resistor RL, that is, it is considered that the cooking device on which the inverter is installed is a mechanical microwave oven.

[0083] For example, when the first voltage is 5 volts, when the voltage transmitted by the second communication circuit 1044 is 5 volts, it is considered that the second sub-interface 1024 is not connected to the gear resistor RL. If the voltage transmitted by the second communication circuit 1044 is less than 5 volts, it is considered that the second sub-interface 1024 is connected to the gear resistor RL, that is, the cooking equipment on which the inverter is installed is considered to be a mechanical microwave oven.

[0084] In some embodiments, optionally, the first sub-interface 1022 includes a first terminal pin A and a second terminal pin B, the first terminal pin A is used to receive a pulse width modulation signal, and the second terminal pin B is used to connect to a reference ground, and the first communication circuit 1042 includes: a first resistor R1, a first end of the first resistor R1 is connected to the first terminal pin A; a second resistor R2, a first end of the second resistor R2 is connected to the second terminal pin B, and a second end of the second resistor R2 is connected to the second end of the first resistor R1; an optocoupler U, a first end of the optocoupler U is connected to the first end of the second resistor R2, a second end of the optocoupler U is connected to the second end of the second resistor R2, a third end of the optocoupler U is used to be connected to the signal input terminal P of the control chip 106, and a fourth end of the optocoupler U is used to access the first power supply VCC1; a third resistor R3, a first end of the third resistor R3 is connected to the third end of the optocoupler U, and a second end of the third resistor R3 is grounded GND.

[0085] In this embodiment, the first terminal pin A can be connected to the computer board 200 to receive the pulse width modulation signal from the computer board 200. By setting the second terminal pin B, the second terminal pin B can be used as a reference to confirm the voltage of the pulse width modulation signal.

[0086] In one embodiment, the second end pin B is used to connect to the ground point EARTH of the housing of the cooking device.

[0087] Among them, after the first resistor R1 and the second resistor R2 are connected together, they are connected in series between the first end pin A and the second end pin B. Therefore, as the voltage of the pulse width modulation signal changes, the voltage across the second resistor R2 also changes, so that the light-emitting diodes set at the first end of the optocoupler U and the second end of the optocoupler U emit light, and correspondingly, the photosensitive diodes set at the third end of the optocoupler U and the fourth end of the optocoupler U receive the light emitted by the light-emitting diode and are turned on, thereby outputting a corresponding voltage signal based on the third end of the optocoupler U. The above voltage signal can be reflected at the first end of the third resistor R3, thereby realizing the transmission of the pulse width modulation signal.

[0088] In this embodiment, the use of the optical coupler U can isolate the computer board 200 from the control chip 106, thereby reducing the probability of damage to the control chip 106 due to voltage shock while realizing the transmission of the pulse width modulation signal, thereby improving the safety of the inverter.

[0089] In some embodiments, optionally, the first communication circuit 1042 further includes: a first capacitor C1 , a first end of the first capacitor C1 is connected to the third end of the optical coupler U, and a second end of the first capacitor C1 is grounded.

[0090] In this embodiment, the first capacitor C1 is provided so as to utilize the first capacitor C1 to filter the signal interference outputted from the third terminal of the optical coupler U, thereby ensuring the accuracy of the pulse width modulation signal.

[0091] In some embodiments, the value of the first capacitor C1 can be determined according to actual usage requirements, which will not be elaborated here.

[0092] In some embodiments, optionally, the first communication circuit 1042 further includes: a fourth resistor R4 , and the fourth resistor R4 is located between the third end of the optical coupler U and the signal input end P of the control chip 106 .

[0093] In this embodiment, since the signal outputted by the third terminal of the optical coupler U directly acts on the signal input terminal P of the control chip 106, when the current of the signal is relatively large, it is easy to cause overcurrent in the control chip 106, thereby causing the control chip 106 to burn out due to overcurrent.

[0094] By providing the fourth resistor R4 , the fourth resistor R4 is used to limit the current flowing through the control chip 106 , thereby reducing the probability of the control chip 106 being damaged due to overcurrent, thereby improving the safety of the inverter.

[0095] In some embodiments, optionally, the first sub-interface 1022 also includes a third terminal pin C, and the first communication circuit 1042 also includes: a fifth resistor R5, a first end of the fifth resistor R5 is connected to the second terminal pin B, and a second end of the fifth resistor R5 is connected to the third terminal pin C; wherein the voltage doubling circuit 108 connected to the magnetron is connected to the reference ground through the fifth resistor R5.

[0096] In this embodiment, the fifth resistor R5 and the third terminal C are provided so that the first communication circuit 1042 can be used to transmit the current value flowing through the fifth resistor R5, thereby realizing the detection of current anomaly.

[0097] Specifically, the current value flowing through the fifth resistor R5 can be used to characterize the anode current of the magnetron, and then when the current value flowing through the fifth resistor R5 exceeds the current threshold, protective measures are triggered, such as automatically cutting off the power supply of the cooking device or issuing an alarm signal, to prevent the magnetron from being damaged by overload or overheating, thereby ensuring the stability, reliability and performance of the inverter.

[0098] In addition, the magnetron anode current detection circuit can also be used for power control and regulation of the inverter to meet different working requirements of the electronic microwave oven.

[0099] In some embodiments, optionally, the voltage doubling circuit 108 further includes a ninth resistor R9 , wherein the ninth resistor R9 is connected to the sixth resistor R6 .

[0100] In some embodiments, optionally, the first communication circuit 1042 further includes: a sixth resistor R6 located between the first end and the second end pin B of the fifth resistor R5.

[0101] In this embodiment, the sixth resistor R6 is provided to limit the current flowing through the third terminal C, thereby reducing the reliability of the circuit connected to the third terminal C while ensuring the detection of the current value flowing through the fifth resistor R5.

[0102] In some embodiments, optionally, the second sub-interface 1024 includes a fourth terminal pin D and a fifth terminal pin F, the fourth terminal pin D is used to connect to the gear resistor RL, and the fifth terminal pin F is used to connect to the reference ground, and the second communication circuit 1044 includes: a seventh resistor R7, the first end of the seventh resistor R7 is used to connect to the second power supply VCC2, and the second end of the seventh resistor R7 is connected to the fourth terminal pin D and the voltage input terminal POWER of the control chip 106.

[0103] In this embodiment, when the fourth end pin D is connected to the gear resistor RL, the gear resistor RL and the seventh resistor R7 form a series relationship, and when the second power supply VCC2 provides a voltage, a voltage division is formed on the gear resistor RL. When the resistance of the gear resistor RL is different, the voltage presented by the second end of the seventh resistor R7 is also different, so the detection of whether the second sub-interface 1024 is connected to the gear resistor RL can be realized based on the voltage at the fourth end pin D.

[0104] Specifically, when the fourth end pin D is not connected to the shift resistor RL, the voltage at the second end of the seventh resistor R7 is the same as the voltage provided by the second power supply VCC2, and when the fourth end pin D is connected to the shift resistor RL, the voltage at the second end of the seventh resistor R7 changes with the resistance change of the shift resistor RL.

[0105] Exemplarily, the voltage provided by the second power supply VCC2 is 5 volts. When the fourth terminal pin D is not connected to the gear resistor RL, the voltage at the second end of the seventh resistor R7 is 5 volts. When the fourth terminal pin D is connected to the gear resistor RL, the voltage at the second end of the seventh resistor R7 is less than 5 volts.

[0106] In some embodiments, optionally, the second communication circuit 1044 further includes: a second capacitor C2, a first end of the second capacitor C2 is connected to the fifth terminal pin F, and a second end of the second capacitor C2 is connected to the voltage input terminal POWER of the control chip 106.

[0107] In this embodiment, the second capacitor C2 is provided so as to utilize the second capacitor C2 to filter out the voltage interference connected to the fourth terminal pin D, thereby improving the accuracy of determining whether the second sub-interface 1024 is connected to the gear resistor RL.

[0108] In some embodiments, optionally, the second communication circuit 1044 further includes: an eighth resistor R8 located between the second end of the seventh resistor R7 and the voltage input terminal POWER of the control chip 106 .

[0109] In this embodiment, the eighth resistor R8 is provided so as to limit the current flowing through the voltage input terminal POWER, thereby protecting the control chip 106 and reducing the probability of damage to the control chip 106 due to overcurrent.

[0110] In one embodiment, the utility model provides a cooking device, comprising: a frequency converter as described in any one of the above items.

[0111] In some embodiments, optionally, the cooking device comprises an electronic microwave oven or a mechanical microwave oven.

[0112] In one embodiment, if Figure 3 As shown, in the related technical scheme, the overall control process of the cooking equipment includes: the microwave oven computer board sends a pulse width modulation signal (Pulse Width Modulation, PWM) signal, and uses the communication interface to transmit the above PWM signal to the inverter. After receiving the communication signal, that is, after receiving the PWM signal, the inverter controls the switching device to operate according to different switching frequencies and duty cycles to achieve different output powers.

[0113] Among them, the switching device is also a power switch.

[0114] and Figure 3 In comparison, Figure 4 As shown, in the embodiment of the utility model, the overall control process of the cooking device includes: judging whether it is a mechanical microwave oven, if the judgment result is yes, the microwave oven mechanical knob samples the voltage signal and transmits it to the inverter through the communication interface, if the judgment result is no, the microwave oven computer board sends a PWM signal and transmits it to the inverter through the communication interface, after the inverter receives the communication signal, that is, after receiving the PWM signal or voltage signal, it controls the switching device to operate according to different switching frequencies and duty cycles to achieve different output powers.

[0115] In the embodiments of the utility model, the frequency converter is compatible with electronic and mechanical microwave ovens, so that electronic and mechanical microwave ovens can share a frequency converter, which helps to improve the standardization of the frequency converter, reduce related costs, and increase the application range of the frequency converter.

[0116] In addition, the embodiments of the utility model can construct a mechanical variable frequency microwave oven, which directly makes up for the shortcomings of traditional mechanical microwave ovens that cannot continuously adjust power, greatly improves the performance of mechanical microwave ovens, improves energy efficiency, reduces weight, and adapts to a wider range of market demands.

[0117] The term "first" or "second" in the specification and claims of this application may include one or more of the features explicitly or implicitly. In the textual description of this utility model, unless otherwise specified, "multiple" means two or more. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / " generally means that the objects connected before and after are in an "or" relationship.

[0118] In the claims, specification and drawings of the present invention, the term "multiple" refers to two or more than two. Unless otherwise clearly defined, the terms "upper" and "lower" indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. They are only for the purpose of more conveniently describing the present invention and making the description process easier, and are not intended to indicate or imply that the device or element referred to must have the specific position described, be constructed and operated in a specific position. Therefore, these descriptions cannot be understood as limitations on the present invention. The terms "connect", "install", "fix" and the like should be understood in a broad sense. For example, "connection" can be a fixed connection between multiple objects, or a detachable connection between multiple objects, or an integral connection; it can be a direct connection between multiple objects, or an indirect connection between multiple objects through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood based on the specific circumstances of the above data.

[0119] In the claims, specification and drawings of the present invention, the description of the terms "one embodiment", "some embodiments", "specific embodiments" and the like means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In the claims, specification and drawings of the present invention, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0120] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be subject to various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A frequency converter for cooking equipment, characterized in that: The cooking device comprises a power switch, and the frequency converter comprises: A communication interface, the communication interface being adapted to be connected to a computer board and a gear resistor; A communication circuit connected to the communication interface; a control chip connected to the communication circuit and configured to determine a target device connected to the communication interface according to a signal transmitted by the communication circuit; and In the case where the target device is the computer board, adjusting the output power of the power switch based on a pulse width modulation signal sent by the computer board; In a case where the target device is the level resistor, the output power of the power switch is adjusted based on a voltage corresponding to the level resistor.

2. The frequency converter according to claim 1, characterized in that: The communication interface includes a first sub-interface and a second sub-interface, the first sub-interface is suitable for connecting to the computer board, and the second sub-interface is suitable for connecting to the gear resistor; The communication circuit comprises: a first communication circuit, wherein an input end of the first communication circuit is connected to the first sub-interface, and an output end of the first communication circuit is connected to a signal input end of the control chip; a second communication circuit, wherein an input end of the second communication circuit is connected to the second sub-interface, and an output end of the second communication circuit is connected to a voltage input end of the control chip; Among them, when the first sub-interface is connected to the computer board, the output end of the first communication circuit outputs the pulse width modulation signal, and when the second sub-interface is connected to the gear resistor, the output end of the second communication circuit outputs the voltage corresponding to the gear resistor.

3. The frequency converter according to claim 2, characterized in that: The first sub-interface includes a first terminal pin and a second terminal pin, the first terminal pin is used to receive the pulse width modulation signal, and the second terminal pin is used to connect to a reference ground, and the first communication circuit includes: A first resistor, wherein a first end of the first resistor is connected to the first end pin; a second resistor, wherein a first end of the second resistor is connected to the second end pin, and a second end of the second resistor is connected to the second end of the first resistor; an optical coupler, wherein a first end of the optical coupler is connected to a first end of the second resistor, a second end of the optical coupler is connected to a second end of the second resistor, a third end of the optical coupler is used to be connected to a signal input end of the control chip, and a fourth end of the optical coupler is used to be connected to a first power supply; A third resistor, wherein a first end of the third resistor is connected to a third end of the optical coupler, and a second end of the third resistor is grounded.

4. The frequency converter according to claim 3, characterized in that: The first communication circuit further includes: A first capacitor, wherein a first end of the first capacitor is connected to the third end of the optical coupler, and a second end of the first capacitor is grounded.

5. The frequency converter according to claim 3, characterized in that: The first communication circuit further includes: A fourth resistor, wherein the fourth resistor is located between the third end of the optical coupler and the signal input end of the control chip.

6. The frequency converter according to claim 3, characterized in that: The first sub-interface further includes a third terminal pin, and the first communication circuit further includes: a fifth resistor, wherein a first end of the fifth resistor is connected to the second end pin, and a second end of the fifth resistor is connected to the third end pin; Wherein, the voltage doubler circuit connected to the magnetron is connected to the reference ground via the fifth resistor.

7. The frequency converter according to claim 6, characterized in that: The first communication circuit further includes: The sixth resistor is located between the first end of the fifth resistor and the second end pin.

8. The frequency converter according to claim 2, characterized in that: The second sub-interface includes a fourth terminal pin and a fifth terminal pin, the fourth terminal pin is used to connect to the gear resistor, and the fifth terminal pin is used to connect to the reference ground, and the second communication circuit includes: A seventh resistor, wherein a first end of the seventh resistor is used to connect to a second power supply, and a second end of the seventh resistor is connected to the fourth end pin and a voltage input end of the control chip.

9. The frequency converter according to claim 8, characterized in that: The second communication circuit further includes: A second capacitor, wherein a first end of the second capacitor is connected to the fifth terminal pin, and a second end of the second capacitor is connected to the voltage input terminal of the control chip.

10. The frequency converter according to claim 8, characterized in that: The second communication circuit further includes: The eighth resistor is located between the second end of the seventh resistor and the voltage input end of the control chip.

11. A cooking device, characterized in that: include: A frequency converter as claimed in any one of claims 1 to 10.

12. The cooking device according to claim 11, characterized in that The cooking device comprises an electronic microwave oven or a mechanical microwave oven.

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