JP4556779B2 - High frequency heating device - Google Patents

Description

  The present invention relates to a high-frequency heating apparatus that can be used by incorporating a main body into a portion whose periphery is closed.

  In a high-frequency heating apparatus having an oven function as a heating means, the main body is not limited to being used in a place where the periphery is open (hereinafter referred to as a normal state), and is incorporated in a portion where the periphery is closed. It may be used in a state (hereinafter referred to as an embedded state).

However, conventionally, even in the assembled state, for example, the temperature in the heating chamber, the cooking time, the number of rotations of the cooling fan, and the like, which are conditions during oven cooking, are the same as in the normal state. For this reason, when used in the built-in state, the ambient temperature of the main body rises and the temperature around the cooling fan also rises, so that the temperature of the components in the machine room becomes higher than when used in the normal state. Therefore, constants such as the heater energization rate and energization timing could only be determined under conditions that ensure the component temperature in the minimum space specified in the catalog. Therefore, the heating power required for baking cooking is small, the cooking time is prolonged, or the cooked product becomes dry, and the quality of cooking is impaired.

  In recent years, using a saucer with a high-frequency heating element attached to the bottom surface, after heating the bottom surface of the saucer with high-frequency heating, it is possible to burn up and down without overturning the food by heating the heater from the top surface Products to sell are also on sale.

  In cooking using both high-frequency heating and oven heating, the hot air after cooling the high-frequency generator flows into the machine room, and the oven room temperature also rises due to the oven heating. One of the challenges in development. Furthermore, when it is used in an embedded state, the ambient temperature in the vicinity of the main body rises due to the heat generated from the main body during cooking and the exhaust from the main body, so that the intake air temperature of the cooling fan section for intake air for cooling the main body also Since the temperature rises, the cooling of the electric parts in the main body is severe, and the temperature of the electric parts is prevented from exceeding the limit by reducing the energy for heating the food. As a result, the quality of cooking was also affected.

For this reason, the heating cooker provided with the installation state determination means is proposed. This determines the installation state based on temperature detection by a temperature thermistor, and controls the cooking constant related to the heating cooking of the heating means and the number of rotations of the cooling fan (for example, see Patent Document 1).
Japanese Patent Laid-Open No. 10-169997

However, in the conventional structure, so as not to be affected by seasonal influences and the food, using the temperature sensor for measuring temperature of the temperature sensor and the heating chamber which is incorporated in the machine room, as a specific method, during the preheat By measuring the rise time of the heating chamber, the installation state of the main body is judged, but cooking using both high-frequency heating and heater heating at the same time, especially placing the object to be cooked on a saucer with a high-frequency heating body attached In the cooking mode, it is common to start cooking by placing an object to be cooked on a saucer stored at room temperature without preheating the inside, and preheating is not performed. This method is difficult to realize.

  The present invention solves the above-mentioned conventional problems, and is compatible with both maintaining the quality of cooking and preventing deterioration of electrical components during cooking that uses high-frequency heating and heater heating at the same time, regardless of the normal state or built-in state. An object of the present invention is to provide a high-frequency heating device.

In order to solve the above-mentioned conventional problems, a high-frequency heating device according to the present invention includes a main body having a heating chamber, a heater heating unit provided in the heating chamber, a high-frequency generation unit that generates a high frequency and performs high-frequency heating, comprising a cooling fan for an electric component cooling provided in the main body, a temperature sensor for detecting the temperature of the high-frequency generator, and a saucer stuck high frequency heating element saucer for placing an object to be heated, the heater In a double-sided grill cooking using heating by heating means and heating using high-frequency heating elements by high frequency , a set in which the body is installed in a state where the periphery is closed using the temperature change of the temperature sensor it is determined whether the write state, before a high-frequency heating apparatus for switching and cooking in a conventional cooking and embedded state in accordance with the determination result, after the cooking start, while performing the normal cooking Get the temperature detected by the temperature sensor, it is determined whether embedded state after performing the normal cooking, when determining whether the embedded state, the normal cooking
It is characterized by lowering the high frequency output than when performing .

  Then, even if there is no dedicated temperature detection means for determining whether or not it is in the built-in state, the built-in state can be reliably determined.

  According to the high frequency heating device of the present invention, when it is determined that the main body is installed, the cooking constant related to the heating cooking of the heating means and the rotation speed of the cooling fan are set in the built-in state. By controlling so as to be suitable for use, it becomes possible to use the electrical component within the temperature limit while maintaining the degree of cooking as much as possible.

A first invention includes a main body having a heating chamber, heater heating means provided in the heating chamber, high-frequency generating means for generating high frequency to perform high-frequency heating, and a cooling fan for cooling electrical components provided in the main body And a temperature sensor for detecting the temperature of the high-frequency generator , and a saucer in which a high-frequency heating element is attached to a saucer on which an object to be heated is placed , and heating by the heater heating means and heat generation of the high-frequency heating element by the high frequency In the double-sided grill cooking using the heating used, it is determined whether or not the main body is installed in a state where the surroundings are closed using the temperature change of the temperature sensor, and the determination result A high-frequency heating device that switches between normal cooking and cooking in an embedded state according to the above, after the start of cooking, obtaining the detected temperature of the temperature sensor while performing the normal cooking, the normal cooking A determination is made whether the embedded state after Tsu, when determining whether the embedded state, characterized in reducing the high-frequency output than when performing the normal cooking, freshly Even without adding a temperature sensor dedicated to temperature detection, appropriate control according to the installation state is possible.

Moreover, according to the said structure, appropriate control according to an installation state is attained also in the mode with severe cooling.

Moreover, according to the said structure, the appropriate control according to the installation state is attained in the cooking mode, without turning the to- be-heated object upside down.

In particular, in double-sided grill cooking, after the start of cooking, the temperature detected by the temperature sensor is acquired while performing the normal cooking, and it is determined whether or not it is in an embedded state after performing the normal cooking. It is.

Furthermore, according to the said structure, the high frequency output at the time of cooking which carries out a built-in judgment is set lower than the high frequency output energy at the time of performing normal cooking, so that a built-in judgment is made accurately. is there.

In addition , it is characterized in that it is determined whether or not it is in the built-in state every time it is cooked. Since the built-in state is determined for each cooking without storing it in a memory or the like, the installation conditions are When improved, it is possible to operate in a normal state.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
2 is a front view showing a state in which the open / close door of the high-frequency heating device according to the embodiment of the present invention is opened, FIG. 3 is a cross-sectional view of the high-frequency heating device viewed from the front, and FIG. 4 is a machine room viewed from the right side. FIG. 5 is a block diagram showing an electrical configuration.

  In the figure, a heating chamber 2 having an open front is disposed in a main body 1 of a high-frequency heating device. A door 3 that closes the front surface of the heating chamber 2 is provided on the front surface of the main body 1 so as to be openable and closable. Further, various operation keys 4 for a user to select a cooking menu, start a cooking instruction, and other necessary displays. An operation panel 6 having a display unit 5 for performing the above is provided. Further, a control board (not shown) is disposed on the back side of the operation panel 6, and a control device 7 including a microcomputer, a fuse (not shown), and a heating means are operated on the control board. Drive circuit 8 and the like are provided. Further, a machine room is provided behind the operation panel.

  An upper heater 9 (760 W), which is one of heating means, is disposed on the top surface of the heating chamber 2. A lower heater 10 (600 W), which is one of heating means, is also provided on the lower surface of the heating chamber 2. A rail 12 for holding the tray 11 is provided on the side surface of the heating chamber 2. Since the high frequency absorber 13 is attached to the lower part of the tray 11, the lower part of the food 14 can be burned by high frequency heating. A heating chamber temperature sensor 30 including a thermistor for detecting the temperature in the heating chamber is disposed in the upper right back of the heating chamber 2.

In the machine room, a magnetron 15 of a high-frequency generator is disposed as one of the heating means, located on the right side wall of the heating chamber 2. A cooling fan 17 and an air guide A18 attached to the back plate 16 are arranged on the right side of the magnetron 15 to cool the magnetron 15. An air guide C <b> 19 is installed on the left side of the magnetron 15 to send air into the heating chamber 2. The air guide C19 is provided with an exhaust thermistor 20 that detects the temperature of the magnetron 15. The high frequency oscillated from the magnetron 15 supplies microwaves into the heating chamber 2 through a waveguide 21 from a power supply port 22 provided on the bottom surface of the main body. An inverter power supply 23 that varies the output of the magnetron 15 is disposed above the magnetron 15. An infrared sensor 24 that detects the temperature of the food 14 in the warehouse, a lamp 25 that illuminates the interior, and the like are also arranged in the machine room.

FIG. 5 shows an electrical configuration. In FIG. 5, the control device 7 includes various operation keys 4 including a start switch, an infrared sensor 24 for detecting the temperature of the food, an exhaust thermistor 20 for detecting the temperature of the magnetron 15 of the high frequency generator, and the heating chamber 2. A signal from the heating chamber thermistor 15 for detecting the temperature inside is input. Based on these signals, the control device 7 displays cooking time and accessory information on the display 5 according to a program stored in advance, and via the drive circuit 8, the magnetron 15, the upper heater 9, the lower heater 10, and the cooling. The fan 17 is controlled. Since the magnetron 15 is controlled via the inverter power supply 23, the output can be freely controlled. For example, the upper heater 9 and the high frequency output 300W can be used simultaneously.

  Here, the case of performing double-sided grill cooking using heater heating and high-frequency heating simultaneously will be described. Double-sided grill mode is cooking consisting of three stages.

  First, a high-frequency heating output 600 W is continuously oscillated on the stage 1 to heat the high-frequency absorber 13 of the tray 11 and burn the lower portion of the food 14. Since the magnetron 15 is operating, the cooling fan 17 is rotating at a strong speed.

  Next, in the stage 2, the upper heater 760W and the high frequency heating 300W are continuously output. By continuing to heat the saucer 11 while lowering the output, the upper surface of the food 14 is also burned by starting heating from the upper surface with the upper heater 9 while further scorching the lower surface of the food 14. Since the magnetron 15 is also operating at this stage, the cooling fan 17 is rotating at a strong speed.

  The final stage 3 is a stage in which the upper heater 9 (760 W) and the lower heater 10 (600 W) are continuously operated, and the temperature in the heating chamber 2 is increased and the temperature is increased to the center of the food 14. Since the magnetron 15 is not operating at this stage 3, the rotation of the cooling fan 17 is reduced to a weak rotation. This is because the air that has cooled the magnetron 15 flows into the heating chamber 2 through the air guide C19, and therefore the purpose is to prevent the temperature in the heating chamber 2 from decreasing by reducing the amount of this air. . However, since the number of rotations of the cooling fan 17 is lowered, the temperature in the machine room rises and internal components are in a severe state in terms of temperature.

  In particular, when the main body 1 is installed in a state in which the periphery is closed, the temperature around the main body 1 rises due to the temperature rise of the main body 1 or exhaust heat, so the intake air temperature of the cooling fan 17 also rises. Even if the temperature rise value of the component is kept at a level where there is no problem in the normal state, the temperature limit of the component will be exceeded if it is incorporated in a state where the surroundings are closed. Therefore, when performing double-sided grill cooking, the control device 7 has a function of detecting the exhaust temperature of the magnetron 15 with the exhaust thermistor 20 and determining whether or not it is in an assembled state, and based on the determination result, The on / off time of the heating means and the number of rotations of the cooling fan are set so as to satisfy conditions suitable for the installation state, and the cooking function is performed.

  The flowchart of FIG. 1 shows a part related to the gist of the present embodiment among the contents of control by the control device 7, and this will be described below together with related actions.

  The user turns on the power in a state in which the main body 1 is placed on a table whose periphery is open or in a cabinet whose periphery is closed. When the user selects the double-sided grill key 4b, the flowchart of FIG. 1 starts. First, the control device 7 performs initialization (step S1). Here, the built-in flag is set to 0. At this time, the built-in flag is set to 0 each time. Initializing without remembering the result of the previous cooking. This is because the cooking mode is better when the cooking in the normal state is executed, so that the normal cooking mode is initially activated. And it waits until cooking time setting and the start key 4a are pushed (step S2).

  When the user puts the food 14 on the receiving pan 11 and accommodates it in the heating chamber 2, the cooking time (here, the maximum setting time of 30 minutes) is set with the time setting key 4c, and when the start key 4a is pressed, the control device 7 steps. The process proceeds to S3 and cooking of stage 1 is started.

  The cooking of stage 1 is continuously operated with high frequency heating 600 W to heat the high frequency absorber 13 of the tray 11. Because of the high frequency heating, the magnetron 15 is energized and the temperature rises.

  Next, the control device 7 acquires the level of the exhaust thermistor 20 (step S4) and stores it in step S5. In step S6, it is determined whether or not the cooking time for stage 1 has ended. Each stage operates at the time calculated by the control device 7 according to the time set by the user. When the cooking time is set at 30 minutes, stage 1 operates for 10 minutes and 32 seconds, stage 2 operates for 5 minutes and 13 seconds, and stage 3 operates for the remaining time. These cooking times are programmed in the control device 7 by a calculation formula obtained through experiments. If the end time of stage 1 has not been reached in step S6, the process returns to step S3.

  In step S5, a process of holding the maximum exhaust level acquired in step S4 is performed. Here, the maximum value of the exhaust level in the stage 1 is obtained. When the cooking time of stage 1 has elapsed 10 minutes and 32 seconds, the process proceeds to step S7 and the cooking mode of stage 2 is set.

Even if it moves to the stage 2, the built-in judgment of the control apparatus 7 is not performed immediately, and fixed mask time (3 minutes by this invention) is provided. This is also due to consideration of operating cooking under normal conditions as much as possible. If the mask time has not ended in step S8, the process jumps to step S14 to perform normal cooking. For cooking in the normal state of stage 2, the upper heater 9 (760 W) and the high-frequency output 300 W are energized continuously. In step S15, it is determined whether or not stage 2 is finished. Here, since it has just entered stage 2, the process returns to step S8. Thus, normal cooking in step S14 is executed until the mask time is finished.

  When the mask time ends, the process proceeds to step S9. When it comes to step S9 for the first time, the built-in flag is in a 0 state. Here, the exhaust level at the stage 2 is acquired (step S10). Next, in step S11, the level acquired in step S9 is compared with the constant Pk. The constant Pk is a value obtained by subtracting a certain constant (this time set to 15) from the MAX value of stage 1 held in step S5. The high frequency output of stage 1 is 600 W, while the high frequency output of stage 2 is 300 W.

  When the main body is used in the normal state, the intake temperature of the cooling fan is about room temperature, so that the magnetron 15 is sufficiently cooled and the level of the exhaust thermistor 20 is lowered, but the main body 1 is closed. When installed, the heat generated in the main body 1 and the exhaust heat from the main body 1 are confined in a closed space, so that the ambient temperature in the vicinity of the cooling fan 17 of the main body 1 also rises and the hot air is sent by the cooling fan 17. As a result, a sufficient cooling effect cannot be obtained and the output level of the high-frequency output is reduced, but the decrease value of the exhaust level is smaller than that in the normal state. Therefore, if it is equal to or greater than the constant Pk in step S11, it is determined that the main body is incorporated in the closed space, and cooking is performed with the cooking constant at the time of incorporation (step S13).

  In the present embodiment, the cooking constant when the stage 2 is assembled is such that the upper heater 9 (760 W) is kept energized and the high frequency output is controlled for 30 seconds on and 10 seconds off. The rotation of the cooling fan 17 remains strong because the magnetron 15 is energized. After the masking time is over and the incorporation determination is made, the process jumps from step S9 to step S13, and cooking at the time of incorporation is continued. It continues until the cooking time of stage 2 ends in step S15. When stage 2 ends in step S15, the process proceeds to stage 3.

  In stage 3, first, it is confirmed whether or not the incorporation determination is made in stage 2 (step S16). When the incorporation determination is not made (incorporation flag is 0), normal cooking is performed (step S18). During normal cooking of stage 3, the upper heater 9 (760 W) and the lower heater 10 (600 W) are energized continuously. The cooling fan 17 is controlled at medium rotation after weak rotation for 5 minutes. If it is determined in step S16 that the product is incorporated, cooking is performed during assembly (step S17). When the stage 3 is assembled, the upper heater 9 (760 W) is continuously energized, the lower heater 10 (600 W) is turned on for 30 seconds and turned off for 10 seconds. Rotate. Until the cooking time is over (step 19), the operation is performed in either the cooking at the time of incorporation or the cooking at the normal time. When the cooking time is finished in step 19, the process moves to step 20, the cooking end process such as stopping the drive circuit 8 and sounding the cooking end buzzer is executed, and the double-sided grill cooking is finished.

FIG. 6 shows the relationship between the cooking time and the exhaust level in the normal state and the built-in state. In cooking when installed in a normal state, the exhaust level rises to 75 level in stage 1 and the exhaust level at the time point when the mask time of stage 2 ends is 54 levels. Since the level continues to decrease after that, the built-in determination is not made. On the other hand, when installed in a built-in state (this time, a wooden wall of 20 mm thickness is installed at a position of 65 mm on the left and right and 50 mm on the back with respect to the main body), the exhaust level rises to 76 levels on stage 1 Yes. The exhaust level is constant when about 7 minutes and 30 seconds elapse, because the temperature rise of the magnetron 15 is steep and the high frequency output is reduced to 450 W for the purpose of component protection. In the case of the built-in state, even if the stage 2 is entered, the exhaust level does not decrease much, and 6
Since it is 9 levels and is higher than 76−15 = 61 level, it is determined as an embedded state.

  FIG. 7 is a graph showing cooking times and component (fuse) temperatures in the normal state and the assembled state. As shown in the drawing, in the normal state, the rotation of the cooling fan 17 drops to a weak rotation when entering the stage 3, so that the temperature of the fuse rises. By increasing to medium rotation, the temperature of the fuse also drops and stays within the temperature limit. On the other hand, when operated in the built-in state, the transition to the middle of the stage 2 starts intermittent operation, and the rotation speed of the cooling fan 17 does not decrease to a weak rotation, so the fluctuation of about 80 ° C. Therefore, it can be within the temperature limit.

In this embodiment, when it is determined to be built-in, the stage 2 has a high-frequency output of 300 W, the stage 3 has the lower heater 10 energized , and the upper heater 9 maintains continuous energization. As a result, the upper surface of the food 14 is firmly burnt, and the lower surface is slightly weakened in baked color, but the heating power through which the fire passes is maintained, so the user does not have to turn the food 14 upside down, It becomes possible to cook.

  In the present embodiment, as described above, the normal state is always prioritized by initializing the built-in state, determining for each cooking, and not holding the determination result in the previous cooking. To work. In other words, by giving priority to cooking conditions optimized in normal conditions with good thermal conditions, the quality of cooking is improved.

  Furthermore, since the built-in state is determined each time, even if it has been operating as determined to be in the built-in state so far, by cleaning and organizing, the part around the high-frequency heating device, particularly the machine room (this embodiment) Then, when the installation state on the right side of the main body is changed and the ventilation is improved, or when the temperature is lowered such as in winter and the cooling condition is improved, the operation as a normal state can be performed.

  As described above, according to the high-frequency heating device according to the present invention, when it is determined that the main body is installed in a built-in state, the cooking constant related to heating cooking of the heating means and the rotation speed of the cooling fan are By controlling in a state suitable for use in the built-in state, the cooking quality is almost the same as when the main unit is used in a normal state, and the electrical component is also cooled, so the deterioration of the electrical component Can be prevented.

The flowchart which shows the control content of the high frequency heating apparatus of Embodiment 1 of this invention. Configuration diagram of the main body of the high-frequency heating device Sectional view seen from the front of the high-frequency heating device Configuration of the right side of the same high-frequency heating device Block diagram showing the electrical configuration of the control means Graph of cooking time and exhaust level at the time of double-sided grill cooking in Embodiment 1 of the present invention Graph of cooking time and component temperature during double-sided grill cooking in Embodiment 1 of the present invention

1 Body 2 Heating chamber 9 Upper heater (heater heating means)
10 Lower heater (heater heating means)
11 saucer 13 high frequency absorber 15 magnetron (high frequency generating means)
17 Cooling fan 20 Exhaust thermistor (temperature sensor)

Claims (1)

A main body having a heating chamber; heater heating means provided in the heating chamber; high-frequency generating means for generating a high frequency to perform high-frequency heating; a cooling fan for cooling electrical components provided in the main body; and the high-frequency generator A temperature sensor that detects the temperature of the object and a tray on which a high-frequency heating element is attached to a tray on which an object to be heated is placed , and heating by means of heater heating and heating using high-frequency heating element by high frequency are used. in double-sided grill that, by using the temperature change of the temperature sensor, the body is equal to or an embedded state of being installed in a state in which the periphery is closed, the determination result ordinary cooking in accordance with the A high-frequency heating device that switches between cooking in a built-in state, after the start of cooking, acquiring the temperature detected by the temperature sensor while performing the normal cooking, and incorporating after performing the normal cooking A determination is made as to whether or condition or not, when determining whether the embedded state, high-frequency heating apparatus characterized by reducing the RF output than when performing cooking the normal.