KR20120071989A - A cooking apparatus - Google Patents

Abstract

PURPOSE: A cooking apparatus is provided to output amplified microwaves with high efficiency, and to perform impedance matching while an amplifying unit amplifies microwaves and a capacitor transmits the microwaves to a transmitting unit. CONSTITUTION: A cooking apparatus comprises a cavity, a microwave generating unit, and a microwave transmitting unit. The microwave generating unit generates microwaves. The microwave transmitting unit transmits the generated microwaves to the cavity. The microwave generating unit comprises an amplifier, a capacitor(610), and a stove(620). The amplifier outputs amplified microwaves. The capacitor outputs the amplified microwaves to the microwave transmitting unit. The stove performs harmonic matching of the microwaves at a place between the stove and the amplifier.

Description

Cooking apparatus

The present invention relates to a cooking appliance, and more particularly, to a cooking appliance having improved efficiency.

In general, when a cooking appliance stores and seals food and presses an operation button, a voltage is applied to the high pressure generator, and a commercial voltage applied to the high pressure generator is boosted to power the magnetron generating microwaves, and the magnetron is operated by the magnetron. The generated microwaves are transmitted to the cavity through a wave guide or the like.

At this time, the cooking appliance is to heat the food with friction heat generated by irradiating microwaves generated from the magnetron to the food and vibrating the molecules constituting the food 245 million times per second.

Such a cooking apparatus is easy to control the temperature, it is a situation that is widely spread in the general home due to various advantages such as saving of cooking time, ease of operation.

However, when cooking food using microwaves, there is a problem that a temperature difference occurs partially in the food without being uniformly heated by the surface deviation of the food. In addition, there is a problem that the temperature deviation during cooking also varies depending on the type of food stored in the cooking apparatus.

It is an object of the present invention to provide a cooking apparatus with improved efficiency.

The cooking apparatus according to the embodiment of the present invention for solving the above problems includes a cavity, a microwave generator for generating a predetermined microwave, and a microwave transmitter for delivering the generated microwave to the cavity, The wave generator includes an amplifier for outputting amplified microwaves by performing frequency oscillation and amplification, and a capacitor for outputting the amplified microwaves to the microwave transmitter.

In addition, a cooking apparatus according to an embodiment of the present invention for solving the above problems, a cavity, a microwave generator for generating a predetermined microwave, and a microwave transmitter for transmitting the generated microwave to the cavity The microwave generator includes an amplifier for outputting microwaves amplified by performing frequency oscillation and amplification, and a stub for harmonic matching of the microwaves.

According to an embodiment of the present invention, impedance matching may be performed by including an amplifier for outputting amplified microwaves by performing frequency oscillation and amplification, and a capacitor for outputting the amplified microwaves to a microwave transmitter. Therefore, it is possible to output with high efficiency when outputting the amplified microwave.

On the other hand, by providing a stub at the output terminal of the amplifier, it is possible to perform harmonic matching of the microwave, thereby improving the efficiency at the time of output of the microwave.

On the other hand, by providing an isolation unit for blocking the microwaves reflected from the load in the cavity to be delivered to the amplifier, it is possible to eliminate the noise signal fed back.

On the other hand, by using a plurality of microwaves, the heating efficiency is calculated, and by outputting microwaves of a predetermined frequency in accordance with the calculated efficiency, uniform heating of the object in the cavity is performed.

1 is a partial perspective view of a cooking appliance according to an embodiment of the present invention.
2 is a cross-sectional view of the cooking appliance of FIG.
3 is a block diagram schematically illustrating an example of the inside of the cooking appliance of FIG. 1.
4 is a block diagram schematically illustrating another example of the inside of the cooking appliance of FIG. 1.
FIG. 5 is a circuit diagram schematically illustrating the interior of the solid state power oscillator of FIG. 4.
FIG. 6 is a partial block diagram illustrating the microwave generator of FIG. 4.
FIG. 7 is a diagram illustrating an example of the stub of FIG. 6.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The suffixes "module" and "unit" for components used in the following description are merely given in consideration of ease of preparation of the present specification, and do not impart any particular meaning or role by themselves. Therefore, the "module" and "unit" may be used interchangeably.

1 is a partial perspective view of a cooking appliance according to an embodiment of the present invention, Figure 2 is a cross-sectional view of the cooking appliance of FIG.

Referring to the drawings, the cooking appliance 100 according to an embodiment of the present invention, the door 106 is attached to the cooking window 104 in the front portion of the main body 102 is coupled to open and close, the main body ( The operation panel 108 is coupled to one side of the front of the 102.

The door 106 opens and closes the cavity 134, and although not shown in the drawing, a door choke (not shown) for shielding microwaves may be disposed inside the door 106.

The operation panel 108 includes an operation unit 107 for operating the operation of the cooking appliance, and a display unit 105 for displaying the operation of the cooking appliance, and the like.

The inside of the main body 102 is provided with a cavity 134 having an accommodation space of a predetermined size so that the heating target 140, for example, food is accommodated and cooked by a microwave.

The cavity 134 may be formed in a tubular shape of an approximately rectangular parallelepiped having at least one surface joined to each other and having an open front surface.

For example, the cavity 134 may include an upper plate forming a ceiling, a rear plate forming a rear surface of the cavity 134, and a bottom forming a bottom surface of the cavity 134. It can be formed by a bottom plate (side plate) and the side plate (side plate) forming the side of the cavity (134). On the other hand, the door 106 may be disposed on the front of the cavity 134. In this case, a front plate that forms the front surface of the cavity 134 may be formed in an area other than the door 106.

The microwave generator 110 for generating a microwave is installed on the outer surface of the cavity 134, the microwave generated from the microwave generator 110 on the output side of the microwave generator 110, the cavity A microwave transmitter 112 is disposed for guiding the inside of 134.

The microwave generator 110 may include a magnetron, a solid state power amplifier (SSPA) using a semiconductor, or a solid state power oscillator (SSPO) using a semiconductor. have.

Solid-state power amplifiers (SSPAs) have the advantage of taking up less space than magnetrons. On the other hand, SSPOs do not have a voltage controlled oscillator (VCO) and a voltage controlled attenuator (VCA) as compared to a solid state power amplifier (SSPA), thereby providing space. It occupies less and has the advantage of simplifying the circuit configuration.

Meanwhile, the solid state power amplifier (SSPA) or the solid state power oscillator (SSPO) may include hybrid microwave integrated circuits including passive elements (capacitors and inductors) and active elements (transistors, etc.) for amplification; HMIC), or passive elements and active elements may be implemented as single high frequency integrated circuits (MMICs) implemented with one substrate.

The microwave generator 110 may implement a solid state power amplifier (SSPA) or a solid state power oscillator (SSPO) as one module, which may be referred to as a solid state power module (SSPM). .

Meanwhile, according to the exemplary embodiment of the present invention, the microwave generator 110 may generate and output a plurality of microwaves. The frequency range of such microwaves may be around 900 MHz to 2500 Hz. In particular, it may be within a predetermined range around 915 MHz or within a predetermined range around 2450 MHz.

The microwave transmitter 112 transmits the microwave generated and output by the microwave generator 110 to the cavity 134. The microwave transmitter 112 may include a transmission line. The transmission line may be implemented by a waveguide, a microstrip line, a coaxial cable, or the like. In order to send the generated microwaves to the microwave transmitter 112, as shown in the figure, the feeder 142 may be connected.

On the other hand, the microwave transmission unit 112, as shown in the drawing can be implemented in the form of opening with the opening 145 into the cavity 134.

On the other hand, the opening 145 may be formed in various forms such as a slot form. Through the opening 145, the microwaves are released to the cavity 134.

Meanwhile, although one opening 145 is illustrated above the cavity 134 in the drawing, the opening 145 may be disposed below or on the side of the cavity 134, and a plurality of openings may be disposed. It is also possible.

In addition, an antenna may be coupled to the end of the microwave transmitter 112.

Below the microwave generator 110, a power supply 114 for supplying power to the microwave generator 110 is provided.

The power supply unit 114 may include a high voltage transformer for supplying power to the microwave generator 110 by boosting the power input to the cooking apparatus 100 to a high pressure, or generated by one or more switching elements performing a switching operation. An inverter for supplying a high output voltage of about 3500V or more to the microwave generator 110 may be provided.

Meanwhile, a cooling fan (not shown) for cooling the microwave generator 110 may be installed around the microwave generator 110.

Although not shown in the figure, a resonance mode converter (not shown) for resonant mode conversion in the cavity 134 may be disposed. Examples of the resonance mode converter (not shown) may include at least one of a stirrer, a rotation table, a sliding table, and a field adjustment element (FAE). Among them, the rotary table and the sliding table may be disposed under the cavity 134, and the stirrer may be disposed at various positions such as the lower, side, and upper portions of the cavity.

In the above-described cooking apparatus 100, the user opens the door 106, puts the heating object 140 into the cavity 134, and then closes the door 106, or closes the door 106 and the operation panel 108. ), In particular, by pressing the start button (not shown) by operating the operation unit 107 is operated.

That is, the power supply unit 114 in the cooking apparatus 100 boosts the input AC power to a high-pressure DC power supply to supply the microwave generator 110, and the microwave generator 110 supplies the corresponding microwave. It generates and outputs, the microwave transmitter 112 transmits the generated microwave to be emitted to the cavity 134. Accordingly, the heating target 140, for example, the food inside the cavity 134 is heated.

3 is a block diagram schematically illustrating an example of the inside of the cooking appliance of FIG. 1.

Referring to the block diagram of FIG. 3, the cooking apparatus 100 according to the embodiment of the present invention may include a microwave generator 110, a microwave transmitter 112, a cavity 134, a controller 310, and It may include a power supply 114.

The microwave generator 110 includes a frequency oscillator 332, a level adjuster 334, an amplifier 336, a directional coupler 338, a first power detector 342, and a second power detector 346. , A microwave control unit 350, a power supply unit 360, and an isolation unit 364. This exemplifies a case composed of a solid state power amplifier (SSPA).

Such components may be configured by combining two or more components into one component, or by dividing one or more components into two or more components as necessary when implemented in an actual application.

The frequency oscillator 332 oscillates to output a microwave of a corresponding frequency by a frequency control signal from the microwave control unit 350. The frequency oscillator 322 may include a voltage controlled oscillator (VCO). According to the voltage level of the frequency control signal, the voltage controlled oscillator VCO oscillates a corresponding frequency. For example, the greater the voltage level of the frequency control signal, the greater the frequency generated by oscillation in the voltage controlled oscillator VCO.

The level adjuster 334 may oscillate the frequency signal oscillated by the frequency oscillator 332 to output a microwave at a corresponding power according to the power control signal. The level adjuster 334 may include a voltage controlled attenuator (VCA).

According to the voltage level of the power control signal, the voltage control attenuation unit VCA performs a correction operation so that microwaves are output at a corresponding power. For example, the greater the voltage level of the power control signal, the greater the power level of the signal output from the voltage control attenuation unit VCA.

The amplifier 336 amplifies the oscillated frequency signal based on the frequency signal oscillated by the frequency oscillator 332 and the power control signal by the level adjuster 334 to output a microwave.

 The directional coupler (DC) 338 transmits the microwaves amplified by the amplifier 336 to the microwave transmitter 112. The microwave output from the microwave transmitter 112 heats the object in the cavity 134.

Meanwhile, microwaves that are not absorbed and reflected by the object in the cavity 134 may be input to the directional coupler 338 through the microwave transmitter 112 again. The directional coupler 338 delivers the reflected microwaves to the microwave control unit 350.

On the other hand, the directional coupler 338 may include a first power detector 342 for detecting the power of the microwave output, and a second power detector 346 for detecting the power of the reflected microwaves. The first power detector 342 and the second power detector 346 may be disposed between the directional coupler 338 and the microwave controller 350 and may be disposed on the directional coupler 338 in a circuit.

The first power detector 342 detects the output power of the microwaves amplified by the amplifier 336 and output to the microwave transmitter 112 via the directional coupler 338. The detected power signal is input to the microwave control unit 350 to be used for calculating the heating efficiency. The first power detector 342 may be implemented with a resistor, a Schottky diode device, or the like for power detection.

Meanwhile, the second power detector 346 detects the power of the reflected microwaves reflected by the cavity 134 and received by the directional coupler 338. The detected power signal is input to the microwave control unit 350 to be used for calculating the heating efficiency. The second power detector 346 may be implemented with a resistor, a Schottky diode device, or the like for power detection.

The microwave control unit 350 operates by receiving driving power from the internal power supply unit 360 constituting the microwave generating unit 110. The microwave control unit 350 may communicate with the control unit 310 to control the operation of the components of the microwave generation unit 110.

The microwave controller 350 may calculate the heating efficiency based on the microwaves reflected without being absorbed by the object among the microwaves emitted into the cavity 134.

Here, Pt represents the power of the microwave emitted into the cavity 134, Pr represents the power of the microwave reflected from the cavity 134, he represents the heating efficiency of the microwave.

According to Equation 1, the heating efficiency he becomes smaller as the power of the microwave to be reflected increases.

On the other hand, when a plurality of microwaves are emitted into the cavity 134, the microwave control unit 350 calculates the heating efficiency (he) for each frequency of the plurality of microwaves. This heating efficiency calculation, according to an embodiment of the present invention, can be performed during the entire cooking period.

On the other hand, for efficient heating, the entire cooking section may be performed by dividing the scan section and the heating section. During the scan period, the plurality of microwaves may be sequentially output into the cavity 134 and the heating efficiency may be calculated based on the reflected microwaves. During the heating section, based on the heating efficiency calculated in the scan section, the output period of each microwave is outputted differently, or only a microwave of a predetermined frequency is output. The power of the microwave in the heating section is preferably significantly higher than the power of the microwave in the scan section.

The microwave controller 350 generates and outputs a frequency control signal to vary the output period of the microwave according to the calculated heating efficiency. The frequency oscillator 332 oscillates a corresponding frequency according to the input frequency control signal.

The microwave control unit 350 generates a frequency control signal so that the output period of the microwave is shortened when the calculated heating efficiency he is high. That is, while sequentially sweeping a plurality of microwaves, the output period of each microwave can be varied according to the calculated heating efficiency. In other words, the higher the heating efficiency he, the smaller the corresponding output period. Accordingly, the microwaves can be uniformly absorbed by the heating object in the cavity 134 for each frequency, and the heating object can be uniformly heated.

On the other hand, the microwave control unit 350, it is also possible to control to output the microwave of the corresponding frequency only when the heating efficiency (he) calculated for each frequency is more than the set target heating efficiency. That is, the microwave of low frequency heating efficiency (he) is excluded from the actual heating period, it is possible to efficiently heat the heating object efficiently.

Meanwhile, the directional coupler 338, including the microwave control unit 350, the power supply unit 360, the frequency oscillator 332, the level control unit 334, and the amplifier 336 in the microwave generation unit 110 described above. The first power detector 342, the second power detector 346, and the like may be implemented as one module. That is, it is possible to be all disposed on one substrate, to be implemented as one module.

The microwave control unit 350 calculates the heating efficiency for each microwave based on the microwaves reflected from the inside of the cavity 134 without being absorbed by the food among the microwaves output into the cavity 134. The microwave of the frequency whose heating efficiency is more than the set target heating efficiency can be calculated. The heating time can be calculated based on the calculated heating efficiency of the microwave. For example, the heating efficiency is higher than or equal to the set target heating efficiency, and the higher the heating efficiency is, the smaller the heating time of the microwave of the corresponding frequency can be set. Thereby, uniform heating of the object can be performed.

Meanwhile, the microwave control unit 350 outputs a microwave for heating the food in the cavity 134 to the cavity 134 based on the calculated heating efficiency. To control. At this time, when heating, the power of the microwave output to the cavity 134 is preferably significantly greater than the power of the microwave output to the cavity 134 when measuring the heating efficiency.

On the other hand, the microwave control unit 350, in the heating section, when the heating efficiency based on the microwaves reflected from the inside of the cavity 134 of the output microwaves is less than the reference efficiency, and stops the output of the microwave of the frequency, The microwave generator 110 may be controlled to output the microwave of the next frequency. By this, efficient heating can be performed.

In addition, the microwave controller 350 calculates heating efficiency for each of the plurality of microwaves based on the microwaves reflected from the inside of the cavity 134 among the microwaves output by the amplifier 336. Depending on the heating efficiency, it is possible to set the heating time for each microwave during the heating period.

At this time, the microwave control unit 350, for example, when the first microwave of the plurality of microwaves has a higher heating efficiency than the second microwave, the heating time of the first microwave than the heating time of the second microwave It can be set shorter.

When heating, the microwave control unit 350 may output the same power control signal to the microwave generating unit 110 for each microwave. In addition, the level adjusting unit 334 may output a constant power level according to the input power control signal.

The power supply unit 360 supplies the driving power for the components inside the microwave generating unit 110. The driving power is supplied to the microwave control unit 350 and the amplifier 336. The external power is supplied from the power supply unit 114 to regulate power to the inside of the microwave generator 110.

The isolation unit 364 is disposed between the amplifier 336 and the directional coupler 338, and passes the microwaves when passing the microwaves amplified by the amplifier 336 to the cavity 134. The microwaves reflected from 134 block. The isolation unit 364 may be implemented as an isolator. The microwaves reflected from the cavity 134 are absorbed by the resistance inside the isolation 364 and cannot enter the amplifier 336. The reflected microwaves are prevented from entering the amplifier 336.

The microwave transmitter 112 transmits the microwave generated and output by the microwave generator 110 to the cavity 134. The microwave transmitter 112 may include a transmission line. The transmission line may be implemented by a waveguide, a microstrip line, a coaxial cable, or the like.

Meanwhile, in order to transmit the generated microwaves to the microwave transmitter 112, the feeder 142 may be connected as shown in the drawing.

The control unit 310 controls the entire system of the cooking appliance in response to the signal received from the operation unit 107. The controller 310 may communicate with the microwave controller 350 of the microwave generator 110 to control the operation of internal components of the microwave generator 110. The controller 310 may control the display unit 105 to externally display the current operation of the cooking appliance, the remaining cooking time, the type of cooking, and the like.

The power supply unit 114 may include a high voltage transformer for supplying power to the microwave generator 110 by boosting the power input to the cooking apparatus 100 to a high pressure, or generated by one or more switching elements performing a switching operation. An inverter for supplying a high output voltage of about 3500V or more to the microwave generator 110 may be provided. In addition, the power supply unit 114 supplies a driving voltage to the control unit 310.

Meanwhile, a block diagram of the cooking appliance 100 shown in FIG. 3 is a block diagram for one embodiment of the present invention. Each component of the block diagram may be integrated, added, or omitted according to the specifications of the cooking apparatus 100 that is actually implemented. That is, two or more constituent elements may be combined into one constituent element, or one constituent element may be constituted by two or more constituent elements, if necessary. In addition, the functions performed in each block are intended to illustrate the embodiments of the present invention, and the specific operations and apparatuses do not limit the scope of the present invention.

4 is a block diagram schematically illustrating another example of the inside of the cooking appliance of FIG. 1.

Referring to the drawings, unlike the microwave generator 110 described above with reference to FIG. 3, a block diagram of a cooking apparatus including a solid power oscillator (SSPO) is shown.

The same components as those described above in FIG. 3 will be omitted.

According to the exemplary embodiment of the present invention, the microwave generator 110 may include a microwave controller 350, a power supply unit 360, a phase shifter 362, an amplifier 336, an isolation unit 364, and a directional coupler. 338 may be included.

As described above, the directional coupler 338 may include a first power detector 342 and a second power detector 346.

There is a difference in that the frequency oscillator 322 and the level adjuster 334 existing in the microwave generator 110 of FIG. 3 are not included, and a phase shifter 362 is added. Referring to the difference from FIG. 3, the microwave control unit 350 outputs the microwave unit 336 to output the microwave for heating the food in the cavity to the cavity 134 based on the calculated heating efficiency he. To control.

The amplifier 336 receives the DC power from the power supply unit 360 and performs its own frequency oscillation and amplification. That is, without an additional frequency oscillator for generating and outputting a frequency oscillation signal, it performs frequency oscillation by itself according to the input of the DC power supply and performs an amplification operation.

The amplifier 336 may include at least one RF power transistor, and when a plurality of RF power transistors are used, the amplifier 336 may be implemented in series, parallel, serial, or parallel mixing to implement multistage amplification. The amplifier 336 may be, for example, an RF power transistor. On the other hand, the output of the amplifier 336 may be approximately 100 to 1000W.

Next, the phase shifter 362 may feed back the output of the amplifier 336 to shift the phase. The amount of phase shift may be adjusted according to the phase control signal of the microwave controller 350. By phase shifting the amplified signal of the predetermined frequency output from the amplifier in this way, it is possible to generate microwaves of various frequencies as described above. For example, the frequency may increase in proportion to the amount of phase shift.

On the other hand, it is preferable that a signal corresponding to approximately 1 to 2% of the amplified signal level at a predetermined frequency is sampled and input to the phase shifter 362. This is considered to be amplified by the amplifier 336 again after the feedback.

Next, the isolation unit 364 supplies the phase shifted signal from the phase shifter 362 to the amplifier 336 again. On the other hand, when the level of the phase shifted signal by the phase shifter 362 is less than the set value, the isolation unit 364 may supply the phase shifted signal to the ground terminal instead of the amplifier 336.

The signal supplied from the isolation unit 364 is amplified again by the amplifier 336. Accordingly, a plurality of microwaves having different frequencies are sequentially output.

As such, since the amplifier 336 performs oscillation and amplification of itself, the microwave generator 110 may be simply implemented. In addition, a plurality of microwaves can be generated and output using the phase shifter 362.

FIG. 5 is a circuit diagram schematically illustrating the interior of the solid state power oscillator of FIG. 4.

Referring to the drawings, the solid state power oscillator (SSPO) of FIG. 5 may include an amplifier 336, a phase shifter 362, a first isolator 364, and a second isolator 366. Can be.

The amplifier 336 receives the DC power from the power supply unit 360 and performs its own frequency oscillation and amplification. That is, without an additional frequency oscillator for generating and outputting a frequency oscillation signal, it performs frequency oscillation by itself according to the input of the DC power supply and performs an amplification operation.

The amplifier 336 may include at least one RF power transistor, and when a plurality of RF power transistors are used, the amplifier 336 may be implemented in series, parallel, serial, or parallel mixing to implement multistage amplification. The amplifier 336 may be, for example, an RF power transistor. On the other hand, the output of the amplifier 336 may be approximately 100 to 1000W.

Next, the phase shifter 362 may feed back the output of the amplifier 336 to shift the phase. The amount of phase shift may be adjusted according to the phase control signal of the controller 310. By phase shifting the amplified signal of the predetermined frequency output from the amplifier in this way, it is possible to generate microwaves of various frequencies as described above. For example, the frequency may increase in proportion to the amount of phase shift.

On the other hand, it is preferable that a signal corresponding to approximately 1 to 2% of the amplified signal level at a predetermined frequency is sampled and input to the phase shifter 362. This is considered to be amplified by the amplifier 336 again after the feedback.

On the other hand, the first isolator 364 is located between the amplifier 336 and the directional coupler 338, and microwaves a plurality of microwaves having different frequencies, sequentially output from the amplifier 336 Supply to the transmitter 112. Specifically, it is to be supplied to the microwave transmitter 112 via the directional coupler 338. On the other hand, when the signal level of the microwave supplied from the amplifier 336 is less than the set value, the first isolator 364 may supply the microwave to the ground terminal instead of the microwave transmitter 112.

Next, the second isolation unit 366 supplies the phase shifted signal from the phase shifter 362 to the amplifier 336 again. On the other hand, when the phase shifted signal level of the phase shifter 362 is less than the set value, the second isolator 366 may supply the phase shifted signal to the ground terminal instead of the amplifier 336.

The signal supplied from the second isolation unit 366 is amplified again by the amplifier 336. Accordingly, a plurality of microwaves having different frequencies are sequentially output.

The feedback transmission line 390 is a transmission line connecting the output terminal of the amplifier 336 and the phase shifter 362. The phase shifter 362 is located on the feedback transmission line 390. According to an embodiment of the present invention, the phase shifter 362 may be configured as an impedance element such as a switch and / or a diode.

6 is a partial block diagram illustrating the microwave generator of FIG. 4, and FIG. 7 is a diagram illustrating an example of the stub of FIG. 6.

First, referring to FIG. 6, the microwave generator 600 according to an embodiment of the present invention includes a high output capacitor 610, a stub 620, and an isolation unit 630. In addition, although not shown in the drawings, as illustrated in FIG. 4 or 5, an amplifier (not shown), a phase shifter (not shown), and a controller (not shown) may be further included.

When the microwave generator 600 is a solid state power amplifier (SSPA), the amplifier (not shown) receives the generated microwaves and performs amplification, and the microwave generator 600 performs the solid state power oscillator (SSPO). ), The amplifier (not shown) may perform frequency oscillation and amplification to output the amplified microwave.

Hereinafter, a description will be given of a case where the microwave generator 600 is a solid power oscillator (SSPO).

An amplifier (not shown) outputs microwaves amplified by performing frequency oscillation and amplification. In order to output a high power microwave, a plurality of RF power transistors are provided, and each RF power transistor may be connected in parallel with each other.

The microwave oscillated and amplified by the amplifier (not shown) is transmitted to the microwave transmitter 112 for output to the cavity. At the output terminal of the microwave generator 600, a capacitor 610 for impedance matching with the microwave transmitter 112 is disposed.

The frequency range of the microwave output through the capacitor 610 may be within a predetermined range (for example, 900 MHz to 950 MHz, specifically 902 MHz to 928 MHz) about 915 MHz in the case of SSPO. Therefore, since the capacitance of the capacitor 610 is inversely proportional, it may be determined according to the frequency range of the microwave.

As such, by performing impedance matching through the capacitor 610, the output of the amplified microwave can be output with high efficiency.

Meanwhile, the capacitor 610 may couple the amplified high power microwave to the delay line 640.

On the other hand, the stub 620 may be disposed between the amplifier (not shown) and the capacitor 610 for the harmonic matching of the microwave. For example, the stub 620 is disposed to limit the third harmonic component or the fifth harmonic component of the frequency of the microwave output from the amplifier (not shown).

For example, when the microwave generator 600 of FIG. 6 is implemented on a circuit board, the stub 620 may be implemented in a micro strip shape due to a limitation in space.

7 shows an example of the stub 620. As shown in the figure, it can be implemented on a circuit board as a parallel strip of micro strip shape. Specifically, in order to limit the third harmonic component (about 2745 MHz in case of SSPO) or the fifth harmonic component (about 4575 MHz in case of SSPO) of the frequency of the microwave output from the amplifier (not shown), The LC value is equivalently implemented in a pattern of predetermined length and width on the line on the substrate.

In this way, through the stub, it is possible to perform harmonic matching of the microwave, thereby improving the efficiency at the output of the microwave.

On the other hand, the isolation unit 630 blocks the microwaves transmitted through the delay line 640 to block the transmission to the amplifier (not shown).

For example, when a portion (about 1 to 5%) of the microwave output through the capacitor 610 is fed back and transmitted through the delay line 640, the noise component mixed in the microwave may be removed. In addition, the isolation unit 630 may block the microwaves reflected from the load in the cavity from being transmitted to the amplification unit (not shown) when the microwaves are transmitted through the delay line 640 through the capacitor 610.

The isolation unit 630 may also perform impedance matching between the delay line 640 and the input terminal. The input terminal may mean a stage after the amplifier (not shown).

Meanwhile, the phase shifter (not shown) may be disposed between the isolation unit 630 and the capacitor 610 or at a previous stage of the isolation unit 630.

Such a phase shifter (not shown) may include at least one impedance element or at least one switch, and may shift the phase of the microwave output from the amplifier based on an impedance variable by the impedance element or the switch. have. The amount of phase shift may be determined according to a control signal of a microwave controller (not shown). As the phase shifts, the amplifier (not shown) may output a plurality of microwaves.

Meanwhile, the microwave controller (not shown) calculates heating efficiency for each frequency using microwaves supplied into the cavity and microwaves reflected from the cavity, and generates microwaves having a predetermined frequency based on the calculated heating efficiency. Can be controlled.

Meanwhile, the capacitor 610 in the microwave generator 600 of FIG. 6 may correspond to the capacitor shown between the amplifier 336 and the phase shifter of FIG. 5, and the delay line 640 of FIG. It may correspond to the feedback transmission line 390 of FIG. 5. In addition, the isolation part 630 of FIG. 6 may correspond to the second isolation part 366 of FIG. 5.

Meanwhile, the cooking apparatus according to the embodiment of the present invention has been described with reference to a cooking apparatus using microwaves, but is not limited thereto and may be combined with various cooking apparatuses. For example, a cooking appliance using a microwave according to an embodiment of the present invention may be coupled to a cooking appliance in the form of an oven using a heater as a heating source. As another example, as a heating source, a cooking appliance using a microwave according to an embodiment of the present invention may be combined with a cooking appliance using an induction heating heater. As another example, as a heating source, a cooking appliance using a magnetron may be combined with a cooking appliance using a microwave according to an embodiment of the present invention.

The cooking apparatus according to the present invention is not limited to the configuration and method of the embodiments described as described above, the embodiments are all or part of each embodiment can be selectively combined so that various modifications can be made It may be configured.

In addition, although the preferred embodiment of the present invention has been shown and described above, the present invention is not limited to the specific embodiments described above, but the technical field to which the invention belongs without departing from the spirit of the invention claimed in the claims. Of course, various modifications can be made by those skilled in the art, and these modifications should not be individually understood from the technical spirit or the prospect of the present invention.

Claims (9)

Cavity;
A microwave generator for generating a predetermined microwave; And
It includes; Microwave transmission unit for delivering the generated microwave to the cavity,
The microwave generator,
An amplifier for outputting an amplified microwave by performing frequency oscillation and amplification; And
And a capacitor for outputting the amplified microwave to the microwave transmitter. The method of claim 1,
The microwave generator,
And a stub for harmonic matching of the microwave, between the amplifier and the capacitor. The method of claim 2,
The stub is,
A cooking apparatus, characterized in that the parallel strip of the micro strip shape. The method of claim 1,
The microwave generator,
And an isolation unit for blocking the microwaves reflected from the load in the cavity from being transmitted to the amplification unit. The method of claim 1,
The microwave generator,
And a phase shifter having at least one impedance element or at least one switch, the phase shifter shifting a phase of the microwave output from the amplifier based on the impedance variable by the impedance element or the switch. Cooking apparatus, characterized in that. The method of claim 1,
The microwave generator,
A control unit configured to calculate heating efficiency for each frequency using microwaves supplied into the cavity and microwaves reflected from the cavity, and to control to generate microwaves of a predetermined frequency based on the calculated heating efficiency. Cooker, characterized in that to output. Cavity;
A microwave generator for generating a predetermined microwave; And
It includes; Microwave transmission unit for delivering the generated microwave to the cavity,
The microwave generator,
An amplifier for outputting an amplified microwave by performing frequency oscillation and amplification; And
And a stub for harmonic matching of the microwaves. The method of claim 7, wherein
The microwave generator,
And an isolation unit for blocking the microwaves reflected from the load in the cavity from being transmitted to the amplification unit. The method of claim 7, wherein
The microwave generator,
A control unit configured to calculate heating efficiency for each frequency using microwaves supplied into the cavity and microwaves reflected from the cavity, and to control to generate microwaves of a predetermined frequency based on the calculated heating efficiency. Cooker, characterized in that to output.

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