JP3863886B2 - High frequency heating device - Google Patents

Description

  The present invention relates to a high-frequency heating device, and more particularly to a high-frequency heating device that performs heating so as to control the temperature of an object to be heated.

Conventionally, in a microwave oven or the like, a technique has been disclosed in which heating is performed using an infrared sensor while detecting the temperature of an object to be heated such as an object to be heated in a heating chamber (for example, Patent Document 1).
Japanese Patent Laid-Open No. 10-220771

  However, for such a technique, it is always required to accurately set the temperature of the object to be heated to the target temperature at the end of heating.

  The present invention has been conceived in view of such circumstances.

A high-frequency heating device according to an aspect of the present invention includes a heating chamber that houses an object to be heated, an infrared sensor that detects infrared rays in the heating chamber and detects temperature, and a bottom surface of the heating chamber. A bottom plate on which a heated object is placed, a magnetron that oscillates at a high frequency, a waveguide connected to the magnetron, and a high frequency from the magnetron supplied via the waveguide, the bottom surface of the heating chamber A rotating antenna that is supplied to the heating chamber while diffusing from the antenna, an antenna receiving portion that is disposed below the bottom plate, and stores the rotating antenna, and the object to be heated is placed and stored in the heating chamber, A heating pan in which a high-frequency heating element that absorbs the high frequency to generate heat is disposed on the back surface, a rail that is formed on the left and right wall surfaces of the heating chamber and supports the heating tray housed in the heating chamber; Of the high frequency radiated from the rotating antenna, the heated object is directly heated by the high frequency that has not been absorbed by the high frequency heating element of the heating dish, and is provided between the high frequency heating element and the heating chamber wall surface. Further, a reaching path that allows the high frequency wave not absorbed by the high frequency heating element to reach the upper side of the heating dish, and the driving of the magnetron is controlled based on the detected temperature of the infrared sensor, and the heating dish is set to a specific temperature. A control unit capable of performing preheat treatment that heats the rotating antenna, wherein the rotating antenna is disposed so as to overlap a high-frequency heating element of the heating dish housed in the heating chamber, and the control unit is configured to perform the preheat treatment. , The detected temperature of the heating pan detected by the infrared sensor immediately before driving the magnetron, or at the start of driving of the magnetron Serial based on the detected temperature of the heating pan which is detected by the infrared sensor, and determines the magnetron driving time for raising the temperature of the heating pan to a certain temperature.
A high-frequency heating device according to another aspect of the present invention is provided on a heating chamber that houses an object to be heated, an infrared sensor that detects infrared rays in the heating chamber and detects temperature, and a bottom surface of the heating chamber. A base plate on which the object to be heated is placed, a magnetron that oscillates a high frequency, a waveguide connected to the magnetron, and a high frequency from the magnetron supplied via the waveguide, A rotating antenna that diffuses from the bottom of the chamber and supplies it into the heating chamber, an antenna housing portion that is disposed below the bottom plate and houses the rotating antenna, and the object to be heated is placed and housed in the heating chamber. And a heating pan in which a high-frequency heating element that absorbs the high frequency to generate heat is disposed on the back surface, and a tray that is formed on the left and right wall surfaces of the heating chamber and supports the heating pan housed in the heating chamber. Between the high-frequency heating element and the heating chamber wall surface to directly heat the object to be heated by the high-frequency wave radiated from the rotating antenna and not absorbed by the high-frequency heating element of the heating dish. And a path for reaching the high frequency that has not been absorbed by the high frequency heating element to reach the upper side of the heating dish, and the driving of the magnetron is controlled based on the detected temperature of the infrared sensor, and the heating dish A control unit capable of performing preheat treatment for heating to a specific temperature, and the rotating antenna has a portion that overlaps a high-frequency heating element of the heating dish housed in the heating chamber, and the control unit includes: In the pre-heat treatment, the detected temperature of the heating pan detected by the infrared sensor immediately before driving the magnetron, or at the start of driving of the magnetron Serial based on the detected temperature of the heating pan which is detected by the infrared sensor, and determines the magnetron driving time for raising the temperature of the heating pan to a certain temperature.

  According to the present invention, the time for oscillating the magnetron to raise the heating dish to a specific temperature is determined according to the situation where the heating dish is placed, and more accurately the heating dish is set to a specific temperature. can do.

  Embodiments of the present invention will be described below with reference to the drawings.

[1. Microwave oven structure]
FIG. 1 is a perspective view of a microwave oven according to an embodiment of the present invention. The microwave oven 1 mainly includes a main body and a door 3. The main body is covered by the exterior portion 4 and supported by a plurality of legs 8. In addition, an operation panel 6 for a user to input various information to the microwave oven 1 is provided on the front surface of the main body.

  The door 3 is configured to be openable and closable with the lower end as an axis. A handle 3 </ b> A is provided on the upper portion of the door 3. FIG. 2 shows a front view of the operation panel 6 and FIG. 3 shows a front view of the microwave oven 1 when the door 3 is opened.

  A main body frame 5 is provided inside the main body 2. A heating chamber 10 is provided inside the main body frame 5. A hole 10 </ b> A is formed in the upper right side of the heating chamber 10. A detection path member 40 is connected to the hole 10 </ b> A from the outside of the heating chamber 10. A bottom plate 9 is provided on the bottom surface of the heating chamber 10.

  A transparent heat-resistant glass 3B is fitted into the central portion of the door 3 so that the inside of the heating chamber 10 can be visually recognized from the outside even when the door 3 is in a closed state. Inside the heating chamber 10 of the door 3, a resin choke cover 3 </ b> C is provided to fill a gap between the outer periphery of the contact surface 3 </ b> D that contacts the main body frame 5 and the door 3 main body. The high frequency leaking from the gap between the contact surface 3D and the main body frame 5 is covered with a choke cover 3C and is prevented from leaking outside the heating chamber 10 by a choke structure (not shown) formed in the door 3.

  The operation panel 6 includes a display unit 60 that includes a liquid crystal panel or the like and displays various information, an adjustment knob 608, and various keys. The adjustment knob 608 is used when inputting various information such as numerical values.

  For this reason, the start key 601 is operated when various types of cooking are started. The range baking key 602 is operated when the food is heated by the range baking pan 80 as described later. The favorite temperature key 603 is operated when inputting the desired temperature when the adjustment knob 608 is operated to cook the food to the desired temperature.

  Moreover, in the microwave oven 1, automatic cooking according to various menus is possible, and the strength of the finish can be adjusted by operating the keys 604 and 605. The grill key 606 is operated when the food in the heating chamber 10 is cooked with a heater (not shown). The deodorizing key 607 is operated when the heating chamber 10 is deodorized.

  The microwave oven 1 can be configured to place a plurality of trays (or a range baking dish 80 described later) in the heating chamber 10. The oven stage adjustment key 609 is operated to input whether oven cooking in the heating chamber 10 is performed in one stage or two stages. The fermentation key 610 is operated when fermenting bread dough and the like. The range output key 611 is operated when changing the high frequency output oscillated in the microwave oven 1. The thawing key 613 is operated when the frozen food is thawed. When the thawing key 613 is operated twice, the microwave oven 1 performs cooking for thawing the frozen sashimi. The cancel key 614 is operated when canceling a key operation in the middle of input.

  In the microwave oven 1, a microwave oven pan 80 (see FIG. 4) can be placed in the heating chamber 10. In the heating chamber 10, rails 103, 104, 106, and 107 for supporting the range baking dish 80 are formed so as to protrude inside the heating chamber 10. The rails 103 and 104 and the rails 106 and 107 are formed so as to be connected on a horizontal line.

  Concave portions 101 and 102 are formed between the rails 103 and 104 and the rails 106 and 107, respectively. The recesses 101 and 102 are formed so as to protrude outward from the heating chamber 10.

  The rails 103, 104, 106, 107 and the recesses 101, 102 can be formed, for example, by pressing a sheet metal constituting the wall surface of the heating chamber 10.

  FIG. 4 is a perspective view of the range baking dish 80. 5 and 6 are a rear view and a front view of the range baking dish 80, and FIG. 7 is a cross-sectional view taken along the line VII-VII in FIG.

  Hereinafter, with reference to FIGS. 4-7, the structure of the range baking dish 80 is demonstrated.

  The range baking dish 80 has an outer peripheral part 80D which is a plate extending in the horizontal direction on the outer periphery thereof, and a bottom part 80B. The outer peripheral portion 80D and the bottom portion 80B are connected by a wall portion 80E. A groove 80A is formed at the outer edge of the bottom portion 80B and at the connection portion with the wall portion 80E so as to surround the entire periphery of the bottom portion 80B.

  A high frequency heating element 81 is deposited on the back surface of the bottom 80B. The high-frequency heating element is a substance that generates heat by absorbing high frequency, and includes a conductive material, more specifically, a conductive material in which molybdenum is added to tin oxide. The thickness of the deposited film is preferably about 8 × 10 −8 m and the resistivity is about 2 to 6 (Ω / m). In FIG. 5, the surface of the high-frequency heating element 81 is shown hatched.

  Legs 80 </ b> C are formed at the four corners of the back surface of the range baking dish 80. As shown in FIG. 7, in the range baking dish 80, the bottom of the leg 80C, the bottom of the bottom 80B (the part corresponding to the back surface of the groove 80A), and the height of the bottom of the high-frequency heating element 81 are different. Z, Y, and X are in order from the lowest. Thereby, even when the microwave oven 80 is taken out of the heating chamber 10 and placed on a mounting surface such as a table in a state where the high-frequency heating element 81 is heated and heated in the heating chamber 10, Prior to the heating element 81, the leg 80 </ b> C or the bottom portion 80 </ b> B is in contact with the placement surface. Thereby, it can be avoided that high heat is applied from the high-frequency heating element 81 to the mounting surface. By configuring the range baking dish 80 in this way, even if the range baking dish 80 is placed on the door 3 opened as shown in FIG. As a result of the choke cover 3C being melted in contact with 3C, the gap between the contact surface 3D and the main body frame 5 is widened, so that leakage of high frequency in the heating chamber 10 can be avoided.

  Further, as shown in FIG. 5, the high-frequency heating element 81 is deposited at a position away from the end of the outer peripheral portion 80D by a distance W or more and inside the groove 80A. In order to send the high frequency efficiently on the heating pan 80, the distance W may be λ / 4 (1/4 of the wavelength) or more when the wavelength of the high frequency supplied into the heating chamber 10 is λ. preferable. That is, when microwaves are oscillated as a high frequency in the microwave oven 1, the distance W is preferably about 3 cm or more. When the distance W is 5 cm, about 75% to 80% of the high frequency supplied from the magnetron 12 is absorbed by the high frequency heating element 81, and about 20% to 25% is transmitted through the range baking dish 80. Then, it is sent above the range baking dish 80.

  8 is a cross-sectional view taken along the line VIII-VIII in FIG. For convenience, some members are omitted in FIG.

  An infrared sensor 7 is attached to one end of the detection path member 40. The infrared sensor 7 catches infrared rays in the heating chamber 10 through the hole 10A. A magnetron 12 is provided inside the exterior portion 4 so as to be adjacent to the lower right of the heating chamber 10. A waveguide 19 that connects the magnetron 12 and the lower part of the main body frame 5 is provided below the heating chamber 10. A rotating antenna 21 is provided between the bottom of the main body frame 5 and the bottom plate 9. An antenna motor 16 is provided below the waveguide 19. The rotating antenna 21 is connected to the antenna motor 16 by the shaft 15 and rotates when the antenna motor 16 is driven.

  In the heating chamber 10, the food that is the object to be heated is placed on the bottom plate 9 or the range baking dish 80. The range baking dish 80 is accommodated in the heating chamber 10 with the outer peripheral portion 80 </ b> D supported on the rails 103, 104, 106, and 107.

  The high frequency generated by the magnetron 12 is supplied into the heating chamber 10 from the bottom surface of the heating chamber 10 while being stirred by the rotating antenna 21 via the waveguide 19. Thereby, the food in the heating chamber 10 is heated.

  In FIG. 8, the flow of the high frequency supplied into the heating chamber 10 is indicated by a white arrow. Further, the size of the arrow schematically shows the high-frequency electric field strength. The high frequency supplied into the heating chamber 10 is absorbed by the high frequency heating element 81. As a result, the high-frequency heating element 81 is heated, heat is supplied from the high-frequency heating element 81, and the food on the microwave oven pan 80 is heated. The high-frequency flow in this case is shown by a large arrow below the high-frequency heating element 81 in FIG.

  Moreover, the high frequency supplied into the heating chamber 10 permeates through the outer edge of the range baking dish 80 or passes between the range baking dish 80 and the wall surfaces of the recesses 101 and 102. It reaches above the plate 80. As a result, the food on the microwave oven 80 is directly supplied with a high frequency and heated. The high-frequency flow in this case is shown by large arrows at the top and bottom of the outer edge end portion of the range baking dish 80 in FIG.

  In the present embodiment, a portion of the heating chamber 10 below the range baking dish 80 and an outer edge end of the range baking dish 80 where the high-frequency heating element 81 is not deposited (the outer edge of the bottom 80B, the outer peripheral part 80D, the wall A portion including the portion 80E) or the recesses 101 and 102 to reach the upper side of the heating dish (the range baking dish 80) through the high-frequency wave introduced from the waveguide into the heating chamber without passing through the high-frequency heating element. Is configured. When the distance W (see FIG. 5) is set to λ / 4 or more, the dimension in the direction intersecting the high-frequency traveling direction in the reaching path is set to λ / 4 or more.

  Further, in FIG. 8, a part of the high frequency that is not converted into heat and is transmitted through the high frequency heating element 81 is indicated by a small arrow above the center portion of the range baking dish 80. Further, heaters are provided above and below the heating chamber 10 (the grill heater 51 on the upper side and the lower heater 52 on the lower side), which are omitted in FIG.

  In the present embodiment, the rails 103 and 104 and the rails 106 and 107 are provided with rails that support the range baking dish 80 from below at intervals on the right side and the left side in the heating chamber 10, respectively. It is composed of a plurality of members. Thereby, compared with the case where the rail 103 and the rail 104 or the rail 106 and the rail 107 are connected and configured as a single rail extending from the front side to the back side in the heating chamber 10, heating is performed. Since there are many gaps between the inner wall surface of the chamber 10 and the end of the range baking dish 80, it becomes easy to send a high frequency above the range baking dish 80.

  Further, a convex portion 101 A for microwave diffusion is provided in the concave portion 101, and a convex portion 102 A for microwave diffusion is provided in the concave portion 102. The convex portions 101 </ b> A and 102 </ b> A have a function of diffusing high-frequency waves passing through the concave portions 101 and 102 into information on the microwave oven pan 80.

[2. Electrical configuration of microwave oven]
FIG. 9 schematically shows the electrical configuration of the microwave oven 1. The microwave oven 1 includes a control circuit 30 that controls the operation of the microwave oven 1 as a whole. The control circuit 30 includes a microcomputer.

  In the microwave oven 1, the AC voltage from the external commercial power supply 41 is rectified by the rectifier bridge 42 and then converted into a DC voltage by the choke coil 43 and the smoothing capacitor 44. The rectifier bridge 42, the choke coil 43, and the smoothing capacitor 44 constitute a rectifier 45 that rectifies the AC voltage of the commercial power supply 41.

  The switching element 46 is composed of an IGBT (insulator gate bipolar transistor), and a free wheel diode 47 and a resonance capacitor 48 are connected in parallel between the collector and emitter thereof to constitute a resonance type switching circuit. The high frequency transformer 54 includes a primary winding 55, a secondary winding 56 and a heater winding 57. An input DC voltage is supplied to the collector of the switching element 46 through the primary winding 55 of the high-frequency transformer 54. The switching element 46 is turned on / off by a drive signal from the drive circuit 58, and an input DC voltage is periodically switched to be converted into a high frequency. The switching element 46, the free wheel diode 47, and the resonance capacitor 48 constitute a frequency conversion device 49. The drive timing of the switching element 46 by the drive circuit 58 is controlled by the control circuit 30.

  The secondary winding 56 of the high-frequency transformer 54 is connected to a voltage doubler rectifier circuit composed of the voltage doubler rectifier capacitor 32 and the voltage doubler rectifier diode 34. The high frequency voltage generated in the winding 56 is voltage doubled rectified to obtain a DC high voltage. A drive power supply unit for supplying anode power between the anode 33 and cathode of the magnetron 12 (also used as a heater for heating the cathode, hereinafter also referred to as the cathode is also used) is constituted by the voltage doubler rectifier circuit. Is done. The current supplied to the magnetron 12 is detected by the current transformer 37, and this detection signal is input to the control circuit 30. The magnetron 12 is grounded on the anode 33 side, and the heater voltage from the heater winding 57 is supplied to the heater 35 of the magnetron 12.

  The microwave oven 1 is provided with a door switch 3X. The door switch 3X opens the circuit when the door 3 is opened, and closes the circuit when the door 3 is closed. Thereby, when the door 3 is opened, it becomes impossible to supply power from the commercial power supply 41 to the magnetron 12. Therefore, by providing the door switch 3X, it is possible to avoid a situation in which the magnetron 21 oscillates the microwave even though the door 3 is open.

  The microwave oven 1 further includes an interior lamp 53 serving as illumination in the heating chamber 10 and an oven thermistor 59 that detects the temperature in the heating chamber 10. The control circuit 30 is inputted with the contents of operations performed on the key input units 601 to 614 (the adjustment knob 608 and various keys on the operation panel) and the detection outputs of the infrared sensor 7 and the oven thermistor 59, and the rotating antenna. 21, and the display content of the display unit 60 is controlled. Further, the control circuit 30 controls the operation of the grill heater 51, the lower heater 52, and the interior lamp 53 by appropriately driving a relay.

[3. Variation of heating chamber of microwave oven]
In FIG. 10, the 1st modification of the heating chamber 10 of the microwave oven 1 of this Embodiment is shown. 10 corresponds to a diagram showing a modification of the main body frame 5 and its peripheral part in FIG. In this modification, the main change from the example shown in FIG. 8 and the like is that four stages of rails for the range baking dish 80 in the heating chamber 10 are provided.

  In FIG. 10, four stages of rails 111, 112, rails 113, 114, rails 115, 116, and rails 117, 118 are shown in the heating chamber 10 from the top. And in FIG. 10, the state in which the range baking dish 80 is arrange | positioned in the highest position set in the heating chamber 10 which made the outer peripheral part 80D contact | abut to the rails 111 and 112 of the uppermost stage is described. Has been.

  In FIG. 10, a grill heater 51 is shown at the top inside the heating chamber 10, and the heat radiated from the heater 51 is indicated by a solid line arrow, and the high frequency oscillated by the magnetron 12 is indicated by a broken line arrow. . Also in this modified example, as described with reference to FIG. 8, the high frequency supplied from the bottom surface of the heating chamber 10 is absorbed by the high frequency heating element 81 and permeates the outer edge end portion of the range baking dish 80. It is guided above the range baking dish 80.

  In the example as shown in FIG. 10, the surface of the food on the microwave oven pan 80 is heated by the high frequency heating element 81, the contents are heated by directly absorbing the high frequency, and further heated by the grill heater 51. And can burn the surface.

  FIG. 11 is a diagram illustrating a second modification of the heating chamber 10 of the microwave oven 1. In addition, FIG. 11 is a right side view of the microwave oven 1 in order to show the positional relationship between the inside of the heating chamber 10 and the door 3, and shows a state in which the right side surface of the main body is omitted.

  A rail 108 is formed above the rails 103 and 104 on the wall surface of the heating chamber 10 of this modification. Although omitted in FIG. 11, a rail 109 (similar to the rail 109 in FIG. 25) is formed on the wall surface of the heating chamber 10 at a position facing the rail 108. The range baking dish 80 can be supported in the heating chamber 10 by the rail 108 and the rail 109.

  Further, in this modification, a convex portion 121 is formed below the rail 104 and in the back of the heating chamber 10. Although omitted in FIG. 11, a convex portion 122 (see FIGS. 12 and 13) is formed on the wall surface of the heating chamber 10 at a position facing the convex portion 121.

  The convex portions 121 and 122 are cases where a metal dish may be stored in the heating chamber 10, and when the magnetron 12 oscillates microwaves, the range baking dish 80 may be placed. However, in order to prohibit the oscillation of the microwave of the magnetron 12 only when the metal dish (enameled dish 100) is placed in the place where the metal dish is not preferred. Is formed. In this modification, examples of such a place include a place on the bottom plate 9 and at a short distance (within 1 cm) from the bottom plate 9. When the microwave is supplied to the heating chamber 10 via the rotating antenna 21 while the metal dish is placed at a distance close to the bottom plate 9, a discharge occurs between the rotating antenna 21 and the enamel dish 100, Because it is dangerous.

  The enamel pan 100 is a dish on which food is placed during oven cooking in which heating is performed only by the heaters (the grill heater 51 and the lower heater 52), and is configured by coating a sheet metal with a bowl. The

  12 and 13 are diagrams schematically showing a cross section of the main body portion of the microwave oven 1 shown in FIG. 11 at a height at which the convex portions 121 and 122 exist.

  First, referring to FIG. 12, when the range baking dish 80 is placed on the bottom plate 9, the convex portions 121 and 122 are located between the corners of the range baking dish 80 and the wall surface of the heating chamber 10. That is, the range baking dish 80 can be stored in the heating chamber 10 even when the height is the same as the height at which the convex portions 121 and 122 exist.

  On the other hand, referring to FIG. 13, when the enamel pan 100, which is a metal dish as described above, is placed on the bottom plate 9, the enamel pan 100 has its corners in contact with the convex portions 121 and 122. As described above, the shape cannot be advanced to the back of the heating chamber 10. That is, the enamel pan 80 is not stored in the heating chamber 10 at the same height as the height of the convex portions 121 and 122. In such a case, as shown in FIG. 11, the enamel pan 100 prevents the door 3 from being closed. If the door 3 is not closed, the door switch 3X opens the circuit shown in FIG. 9 as described above, so that the magnetron 12 cannot oscillate the microwave.

  That is, in the present modification, the convex portions 121 and 122 are formed, and the shape of the corner is different between the microwave oven pan 80 and the enamel pan 100, and therefore, in the heating chamber 10, Even though the range baking dish 80 can be stored at the same height, the enamel pan 100 cannot be stored. Note that, regardless of the height in the heating chamber 10, the range baking dish 80 is blocked by the convex portions 121 and 122 and cannot be housed in the depths like the enamel pan 100 of FIG. 11. There is no.

  Moreover, as shown in FIG. 12, the range baking dish 80 is accommodated in the heating chamber 10 in a state having a dimension L1 in the depth direction and a dimension L2 (> L1) in the width direction. .

  Furthermore, there is a gap by a distance K with respect to the forefront portion 10X of the heating chamber 10. Thereby, even when the range baking dish 80 is accommodated in the heating chamber 10 and the door 3 is closed, a gap of a distance K or more is generated between the range baking dish 80 and the door 3. Therefore, even when the door 3 is closed, air and microwaves below the range pan 80 are easily sent above the range pan 80.

  In this modification, when the microwaves are oscillated in the magnetron 12 in the heating chamber 10 by forming the convex portions 121 and 122, the microwave oven pan 80 can be installed, but the enamel pan 100 is not installed. There was a place where it was possible. That is, the convex portions 121 and 122 constitute the second convex portion of the present invention.

  Further, the heating chamber 10 may be configured to avoid the microwave oscillation of the magnetron 12 when the microwave oven 80 is installed in an unfavorable place when the microwave is oscillated. Such a modification (third modification) will be described with reference to FIGS.

  FIG. 14 is a right side view of the microwave oven 1 in which members similar to those in FIG. 11 are omitted. In this modification, the convex parts 121 and 122 in the modification example shown in FIG. 12 are changed to convex parts 121A and 122A (see FIG. 15) that have moved to the front side in the heating chamber 10. 15 and 16 are diagrams schematically showing a cross section of the main body portion of the microwave oven 1 of FIG. 14 at a height where the convex portions 121A and 122A exist.

  Referring to FIG. 15, the convex portions 121A and 122A are positioned closer to the front side in the heating chamber 10 than the convex portions 121 and 122 (see FIG. 12), so that the range is the same height as the convex portions 121A and 122A. If it is going to store the baking pan 80, it will be obstruct | occluded by convex part 121A, 122A, and the range baking pan 80 will not enter into the back of the heating chamber 10, and it will prevent that the door 3 closes. In this modified example, if the enamel pan 100 is also stored at the same height as the convex portions 121A and 122A, it is blocked by the convex portions 121A and 122A, and does not fully enter the heating chamber 10, and the door 3 Inhibits closing.

  As described above, since L1 <L2 in the range baking dish 80, as shown in FIG. 16, the range baking dish 80 is rotated by 90 ° from the state shown in FIG. Enters the heating chamber 10 without contacting the convex portions 121A and 122A. Therefore, for such a case, it is preferable that convex portions 123 and 124 are formed on the rear surface in the heating chamber 10. Thus, it is possible to reliably avoid the door 3 being closed and the microwave being supplied into the heating chamber 10 in a state where the range baking dish 80 is stored at an undesirably high height.

  The dimension of the heating chamber 10 in the depth direction is “L1 + K” from FIG. Therefore, in the state shown in FIG. 16, the protrusions 123 and 124 protrude from the rear surface of the heating chamber 10 by a distance longer than “L1 + K−L2” in order to prevent the door 3 from being closed by the range baking dish 80. Need to be.

  Next, the 4th modification of the microwave oven 1 is demonstrated. In this modification, as shown in FIG. 17, reflectors 501 to 504 (refer to FIG. 19 for 501 and 502) are provided on the outer periphery of the rotating antenna 21. 17 is a cross-sectional view corresponding to the cross-sectional view of FIG.

  In this modification, as will be described later, the reflectors 501 to 504 are provided on the outer periphery of the rotating antenna 21, so that the microwave supplied from the bottom surface of the heating chamber 10 to the heating chamber 10 via the rotating antenna 21 can be obtained. It is suppressed from flowing near the wall surface of the heating chamber 10 and is efficiently absorbed by the high-frequency heating element 81. As a result, as shown in FIG.

  FIG. 18 is a diagram showing a temperature distribution on the microwave oven pan 80 when the magnetron 12 is oscillated for 3 minutes. FIG. 18A shows a case where the reflectors 501 to 504 are provided. ) Shows a case where the reflection plates 501 to 504 are not provided.

  In FIG. 18 (B), there are portions that reach a high temperature close to 300 ° C. at the four corners of the range baking dish 80, whereas the vicinity of the center of the range baking dish 80 rises only to about 100 ° C. On the other hand, in FIG. 18 (A), although a slightly hot part is seen in the center part and four corners of the range baking dish 80, the whole area is 150 degreeC or more, and many parts are 175 degreeC or more. . That is, by providing the reflectors 501 to 504, the uneven heating on the range baking dish 80 is eliminated.

  Next, the structure and the like of the reflecting plates 501 to 504 will be described in detail with reference to FIGS. 19 and 20. 19 is a cross-sectional view taken along line FF in FIG. 17, and FIG. 20 is a perspective view of the reflecting plate 501.

  Below the heating chamber 10, there are provided a bottom plate housing portion 92 that houses the bottom plate 9 and an antenna housing portion 91 that is located below the bottom plate housing portion 92 and houses the rotating antenna 21. The shape of the surface of the antenna accommodating portion 91 that intersects the traveling direction of the microwave (the surface including the cross section along the line FF shown in FIG. 19) has rounded corners as shown in FIG. It is made into a shape.

  The reflection plate 501 has a plate shape with an L-shaped cross section, and the reflection plates 502 to 504 have the same structure. The reflectors 501 to 504 are made of a material that reflects microwaves. Moreover, the reflecting plates 501 to 504 may be configured by being coated with such a material.

  The reflectors 501 to 504 are arranged between the rounded corners of the square and the rotating antenna 21. The places where the reflectors 501 to 504 are arranged include a place where the distance between the end face of the rotating antenna 21 and the wall surface of the antenna accommodating portion 91 is the longest. Note that the longest example of the distance between the end face of the rotating antenna 21 and the wall surface of the antenna housing portion 91 is Q1 in FIG. 19, and the shortest example is Q2 in FIG. And by arrange | positioning the reflecting plates 501-504 in such a place, it prevents that the microwave supplied in the heating chamber 10 via the rotating antenna 21 spreads to the wall surface vicinity of the heating chamber 10. FIG. Can do. Accordingly, as described with reference to FIG. 18, it is possible to suppress a large amount of microwaves being supplied to the wall surface portion of the heating chamber 10, and it is possible to suppress uneven heating on the range baking dish 80.

  In addition, the reflecting plates 501 to 504 extend beyond the rotating antenna 21 in the traveling direction of the microwave. Specifically, in FIG. 17, the traveling direction of the microwave is considered to be the upward direction, the height of the reflectors 501 to 504 is H1, and the height of the rotating antenna 21 is H2 (<H1). 501 to 504 exist up to a place higher than the rotating antenna 21. Thereby, the reflecting plate 501 can reliably guide the microwave guided to the heating chamber 10 via the rotating antenna 21 upward while suppressing the diffusion in the lateral direction.

  Instead of providing the reflectors 501 to 504, it is also conceivable to change the structure of the wall surface of the antenna accommodating portion 91 as shown in FIG. 21 or FIG.

  In FIG. 21, the cross section of the antenna accommodating portion 91 is a circle. Moreover, in FIG. 22, the cross section of the antenna accommodating part 91 is made into the polygon (octagon). In this way, the cross section of the antenna accommodating portion 91 is circular or polygonal, so that the distance between the end surface of the rotating antenna 21 and the wall surface of the antenna accommodating portion 91 is further reduced and supplied via the rotating antenna 21. It is possible to avoid a large amount of microwaves traveling near the wall surface of the heating chamber 10.

  A modification example in which the reflectors 501 to 504 are provided and the lower heater 52 is provided around the rotating antenna 21 will be described with reference to FIGS. 23 corresponds to the modification of FIG. 17, and FIG. 24 corresponds to the modification of FIG. The lower heater 52 is fixed by a fixing member 52 </ b> A in the antenna housing portion 91.

  As shown in FIGS. 23 and 24, the reflectors 501 to 504 are provided outside the rotating antenna 21 and inside the lower heater 52. Thereby, in the part provided with the reflecting plates 501 to 504, the microwave supplied to the heating chamber 10 via the rotating antenna 21 is moved upward by the reflecting plates 501 to 504 before being diffused by the lower heater 52. Sent to. Thereby, a microwave is sent to the direction which should be sent more correctly.

  Next, a modification in which microwave heating is performed in a mode that matches the height of the range baking dish 80 when the height of the range baking dish 80 in the heating chamber 10 can be changed will be described.

  FIG. 25 is a diagram showing a fifth modification example in which the microwave oven 1 can store the range baking dishes 80 in the upper and lower two stages in the heating chamber 10, and the microwave oven 1 of the present embodiment described above is shown. FIG. 9 is a diagram corresponding to FIG. 8.

  In the heating chamber 10, rails 108 and 109 are provided above the rails 103, 104, 106, and 107 to support the range baking pan 80. The rail 109 has the shape of the left and right objects as the rail 108 (same as that shown in FIG. 11). In this modification, the range baking dish 80 is supported by the rails 103, 104, 106, and 107 (indicated by solid lines in FIG. 25), and is stored in the lower stage and supported by the rails 108 and 109. (The state shown by the broken line in FIG. 25) is stored in the upper stage. 25, the dimension HC (distance from the bottom surface of the antenna housing 91 to the rotating antenna 21) is 10 mm, the dimension HB (distance from the rotating antenna 21 to the bottom plate 9) is 15 mm, and the dimension HA (bottom plate). The distance from 9 to the range baking dish 80 installed in the lower stage is set to 1/8 of the wavelength of the microwave.

  When heating by microwaves is performed, the heating mode in the range pan 80 varies depending on the distance from the bottom plate 9 (the lowest surface on which the object to be heated can be placed in the heating chamber).

  Basically, it is preferable that the range baking dish 80 on which the food is placed is stored at a position away from the bottom plate 9 by 1/8 or more of the wavelength of the microwave. Thereby, the heating unevenness on the range baking dish 80 can be suppressed.

  In addition, FIG. 26 shows that the range baking dish 80 is stored in the upper stage as the temperature distribution on the range baking dish 80 when the rotation of the rotating antenna 21 is stopped and the microwave is supplied to the heating chamber 10 for a predetermined time. FIG. 27 shows a case where the range baking pan 80 is stored in the lower stage. 26 and 27, the microwaves are supplied in the same state except for the storage position of the range baking dish 80. In FIGS. 26 and 27, different hatching is applied for each temperature zone.

  In FIG. 26, the central portion of the range baking dish 80 is mainly heated, and the temperature difference from the surroundings is conspicuous, whereas in FIG. 27, the temperature in the vicinity of the central portion is relatively high. In comparison, the heating unevenness is suppressed.

  And in this modification, when the range baking dish 80 is accommodated in the upper stage, the rotation antenna 21 is stopped at a predetermined stop position to supply microwaves, thereby suppressing uneven heating. In other words, in this modification, the rotation of the rotating antenna 21 is stopped at a position corresponding to the position where the range baking dish 80 is stored, so that the range baking dish 80 is moved according to the position where the range baking dish 80 is stored. The mode for supplying microwaves is changed so that heating unevenness does not occur.

  It is due to the structure of the rotating antenna 21 that the mode in which the microwave is supplied in the heating chamber 10 changes according to the rotation stop position of the rotating antenna 21. FIG. 28 shows a plan view of the rotating antenna 21.

  The rotating antenna 21 is a disk made of metal, but has a structure in which a plurality of portions are hollowed out. A hole 210 in the central portion is fitted into the shaft 15 and serves as a rotation center. Further, the rotating antenna 21 is provided with a first portion 211 extending in a strip shape from the hole 210. Since the first portion 211 has a width W1 of 35 mm, leakage of microwaves traveling in the direction of the arrow M on the first portion 211 is suppressed as much as possible. The length W2 of the first portion 211 is 65 mm. Thereby, microwaves can be emitted relatively strongly from the tip in the M direction of the first portion 211 and the region 213.

  The rotating antenna 21 is fan-shaped cut out from the hole 210 on the side opposite to the first portion 211. Since the distance W3 from the hole 210 to the cutout portion is 45 mm, the emission of microwaves from the regions 212A and 212B is suppressed. A second portion 212 exists in the central portion of the fan-shaped cutout like a bridge that connects the central portion and the outer peripheral portion of the rotating antenna 21. Thereby, the emission of microwaves from the outer peripheral portion of the rotating antenna 21 is promoted.

  Since the rotating antenna 21 is configured as described above, the mode in which the microwave is supplied in the heating chamber 10 changes according to the stop position of the rotating antenna 21, thereby changing the heating mode in the microwave oven 80. To do.

  In the heating chamber 10, it is preferable that the range baking pan 80 is stored in the lower stage. However, depending on the cooking menu, for example, when cooking is performed by combining heating by the grill heater 51 provided in the upper part of the heating chamber 10 and heating by microwaves, the cooking menu may be stored in the upper stage. And in this modification, according to a cooking menu, a user is instruct | indicated by displaying the storage position of the range pan 80 on the display part 60, and the rotation antenna 21 is stopped at the stop position according to the said storage position. The microwave is supplied. For example, in the cooking menu in which the range baking dish 80 is placed in the lower stage, as shown in FIG. 29, the rotating antenna 21 is stopped and microwaves are supplied, and in the cooking menu in which the range baking dish 80 is placed in the lower stage, FIG. As described above, the rotating antenna 21 is stopped in a state where it is rotated 90 ° clockwise from the state shown in FIG.

[4. Variation of range baking pan]
Next, a modified example of the microwave oven pan 80 in the microwave oven 1 of the present embodiment will be described. First, a sixth modification will be described.

  As shown in the fifth modified example described above, in the microwave oven 1, the height at which the microwave oven pan 80 is stored in the heating chamber 10 can be changed. In addition, as described with reference to FIGS. 26 and 27, when the height at which the range baking dish 80 is stored is changed, the temperature distribution in the range baking dish 80 changes. By changing the area on which the high-frequency heating element 81 is deposited in accordance with the height at which the range baking dish 80 is stored, changes in the temperature distribution in the range baking dish 80 can be suppressed. Specifically, the area in which the high-frequency heating element 81 is vapor-deposited in the microwave oven 80 (hereinafter referred to as vapor deposition area) is the height in which the microwave oven 80 is stored (distance from the bottom plate 9). When the wavelength is 1/8 of the wavelength of the microwave supplied to the antenna, the area of the rotating antenna 21 is preferably the same as the horizontal area.

  Moreover, it is preferable that the deposition area becomes larger than the horizontal area of the rotating antenna 21 as the height at which the microwave oven 80 is stored is higher than 1/8 of the microwave wavelength (see FIG. 31). The deposition area is preferably smaller than the horizontal area of the rotating antenna 21 as it becomes lower than 1/8 (see FIG. 32).

  FIG. 31 and FIG. 32 are rear views of the range baking dish 80 in the present modification. In FIG. 31, the position of the rotating antenna 21 overlaps the high-frequency heating element 81, is indicated by a one-dot broken line AN, and is painted white. In FIG. 31, the area where the high-frequency heating element 81 exists (the above-described vapor deposition area) is larger than the area of the rotating antenna 21. On the other hand, in FIG. 32, the position of the rotating antenna 21 is indicated by a one-dot broken line AN, and a portion overlapping with the high frequency heating element 81 is filled with hatching indicating the high frequency heating element 81. In FIG. 32, the area where the high-frequency heating element 81 exists is smaller than the area of the rotating antenna 21.

  Next, a seventh modification of the present embodiment will be described. FIG. 33 is a back view of the range baking dish 80 of the present modification. FIG. 34 is a cross-sectional view taken along the line EE in FIG. In the range baking dish 80 of this modification, irregularities having a depth of about 5 mm are formed on the back surface, and a high-frequency heating element 81A is deposited along the irregularities on the back surface. In addition, high-frequency heating elements 81B to 81G are vapor-deposited on the front surface only at locations corresponding to the convex portions of the unevenness on the back surface. By placing food on the surface, cooking suitable for food such as okonomiyaki, which is generally cooked on an iron plate, can be realized. In FIG. 34, the surface on which the high-frequency heating elements 81B to 81G are deposited appears to have irregularities, but the thickness of the deposited film of the high-frequency heating elements 81A to 81G is 8 similarly to the high-frequency heating element 81. Since it is about × 10 −8 m, unevenness is hardly recognized when actually used.

  FIG. 35 shows a state where the front and back of the range baking dish 80 of FIG. 34 are turned over. In the state shown in FIG. 35, the food is placed on an uneven surface (a surface on which the high-frequency heating element 81 </ b> A is deposited). When food is placed on the uneven surface, cooking suitable for heat cooking of fat such as yakiniku can be realized. This is because the food itself is supported by the concave and convex portions, and the fat that comes out of the food during heating accumulates and separates from the food in the concave and convex portions.

  In addition, on the surface opposite to the uneven surface of the range baking dish 80, the high-frequency heating elements 81B to 81G are deposited only at locations corresponding to the convex portions on the uneven surface. This is because only the portion needs to be hot. In other words, it is avoided that the high-frequency heating element is deposited on a useless portion, and it is also avoided that a place where the temperature does not need to be high becomes high.

  As described above, the high-frequency heating elements are vapor-deposited in different patterns on the front and back sides of the range baking dish 80, so that different modes of cooking can be performed on the front and back sides of the range baking dish 80.

  Moreover, in this Embodiment, it is preferable that the resistivity of the high frequency heat generating body 81 and 81A-81G shall be about 2-6 (ohm / m) by adjusting the thickness. This will be described with reference to FIG. FIG. 36 shows the resistivity of the high-frequency heating element when microwaves are supplied to the heating chamber 10 when a conductive material in which molybdenum is added to tin oxide is used as the high-frequency heating element in the microwave oven 80. It is a figure which shows the relationship between the electric field intensity which the range baking dish 80 reflects, and the electric field intensity which permeate | transmits.

  From FIG. 36, when the resistivity of the high-frequency heating element is about 2 to 6 (Ω / m), the electric field intensity of the microwave reflected by the range baking dish 80 and the electric field intensity of the microwave transmitted by the range baking dish 80 are Same amount. Therefore, in such a case, heat cooking using the range baking dish 80 becomes efficient.

[5. Example of cooking process in microwave oven]
With reference to FIGS. 37-53, the heat cooking process in the microwave oven 1 of this Embodiment is demonstrated. First, it demonstrates based on FIG. 37 and FIG. 38 which are the flowcharts of a heat cooking process.

  The control circuit 30 performs the initial setting in S1, and then selects the manual range baking cooking in which the food is heated by the range baking dish 80 and the preheating temperature and cooking time are manually input in S2. It is determined whether or not. Specifically, this determination is made by determining whether or not the range baking key 602 has been pressed twice within a predetermined time. If it is determined that manual range cooking has been selected, the preheating temperature and cooking time are set in S3 as input by the user using the adjustment knob 608, and the process proceeds to S5. In the range baking cooking, two stages are set for microwave heating by the magnetron 12. These two stages are called a first stage and a second stage. And in S3, the cooking time of each of the first stage and the second stage is set by processing the inputted cooking time in a predetermined manner. In addition, when shifting from the first stage to the second stage, as will be described later, a buzzer notification is once given, and an instruction is given to the user to turn the food on the range baking dish 80 over.

  On the other hand, if it is determined in S2 that manual range-cooking cooking has not been selected, automatic range-cooking is performed in S4, in which food is heated by the range baking dish 80, and the preheating temperature and cooking time are automatically determined. It is determined whether cooking has been selected. Specifically, this determination is made by determining whether or not the range baking key 602 has been pressed only once within a predetermined time. And if it is judged that automatic range baking cooking was selected, a process will be advanced to S5 as it is. If it is determined in S4 that automatic range baking cooking has not been selected, the process proceeds to S12.

  Note that the setting of the preheating temperature and cooking time in S3 is omitted when automatic range baking cooking is selected because the preheating temperature and cooking time are determined in advance in automatic range baking cooking. is there.

  In S5, the control circuit 30 waits for an operation for starting heating (for example, pressing the start key 601), and advances the process to S6.

  In S6, the control circuit 30 starts driving the magnetron 12, and in S7, preheat treatment is performed. As a result, the high-frequency heating element 81 (81 </ b> A to 81 </ b> G) of the range baking dish 80 is heated and preheating is given to the range baking dish 80.

  When the pre-heat treatment of S7 is completed, the control circuit 30 stops driving the magnetron 12 and notifies the completion of the pre-heat treatment by a buzzer or the like in S8. Then, in S9, after waiting for an operation for starting heating, the process proceeds to S10. At the end of the pre-heat treatment in S8, a notification that the temperature of the microwave oven 80 is high is also given. This is because the range baking dish 80 becomes high temperature in a relatively short time, so that the user can fully recognize that the range baking dish 80 is hot.

  In S10, the control circuit 30 executes the range baking cooking process. When the cooking process is completed, the control circuit 30 notifies it in S11 and returns the process to S2.

  On the other hand, in S12, the control circuit 30 determines whether or not manual double-sided baking cooking, in which food is heated by the grill heater 51 and the range baking dish 80 and the cooking time is manually input, is selected. To do. Specifically, this determination is made by determining whether the grill key 606 has been pressed twice within a predetermined time. If it is determined that manual double-sided cooking is selected, the cooking time is set as input by the user using the adjustment knob 608 in S13, and the process proceeds to S19. In manual double-sided baking cooking and double-sided baking cooking described later, two stages are set, a first stage that is microwave heating by the magnetron 12 and a second stage that is heating by the grill heater 51.

  On the other hand, if it is determined in S12 that manual range-cooking cooking has not been selected, in S14, cooking is performed by heating food by the grill heater 51 and the range baking dish 80, and the cooking time is automatically determined. It is determined whether or not double-sided cooking is selected. Specifically, this determination is made by determining whether or not the grill key 606 has been pressed only once within a predetermined time. If it is determined that automatic double-sided baking cooking has been selected, the cooking time (first stage, second stage, cooking time) corresponding to the cooking course is read and set in S15, and the process proceeds to S19. The cooking course is a course corresponding to the cooking course number selected by the user by rotating the adjustment knob 608 on the operation panel 6 after automatic double-side baking cooking is selected.

  In S19, the control circuit 30 waits for an operation for starting heating (for example, pressing the start key 601), and then advances the process to S20.

  In S20, the control circuit 30 calculates the preheating time from the cooking time set in S13 or S15, and proceeds to S21. Note that the preheating time is calculated according to a predetermined mode. Note that the preheating time is longer as the cooking time is longer, such as 3 minutes if the cooking time is less than 5 minutes, and 5 minutes if the cooking time is 5 minutes or more and less than 10 minutes. Is calculated.

  In S21, the control circuit 30 starts driving the magnetron 12, and if it is determined in S22 that the preheating time has elapsed, the driving of the magnetron 12 is stopped in S23, and the preheat treatment is completed in S24. Is notified by a buzzer or the like. Then, in S25, after waiting for an operation for starting heating, the process proceeds to S26.

  In S26, the control circuit 30 executes the double-sided baked cooking process, and when it is finished, notifies it in S27 and returns the process to S2.

  On the other hand, in S16, the control circuit 30 determines whether or not other cooking has been selected. The other cooking is, for example, thawing cooking when the thawing key 613 is pressed. If it is determined that such cooking has been selected, the cooking time is set as input by the user in S17, cooking is performed for the cooking time in S18, and the process returns to S2. On the other hand, if it is determined in S16 that such other cooking is not selected, the process returns to S2.

  Next, the preheat treatment will be described with reference to FIGS. FIG. 39 is a flowchart of the preheat treatment subroutine of S7.

  In the pre-heat treatment, the control circuit 30 first starts counting the counter t in S701.

  In step S702, output setting A processing is executed. The contents of the output setting A process will be described with reference to FIG.

  In the output setting A process, the control circuit 30 first detects the temperature Ti of the inverter (frequency conversion circuit 49) in S7020.

  Next, in S7021, it is determined whether a timer ta described later is being counted. Note that the timer ta means that in the preheating control A process described later, Tcave (the detected temperature is the average temperature within the scanning range detected by the infrared element that is the target in the preheating control) from Tcave1 (predetermined temperature). This is a timer for measuring the time required to change to Tcave2 (a predetermined temperature higher than Tcave1). If the timer ta is being counted, the process proceeds to S7025. If not, the process proceeds to S7022.

  In S7022, the control circuit 30 determines whether Ti detected in S7020 is less than a predetermined value Ti1. If Ti is less than Ti1, the process proceeds to S7023; otherwise, the process proceeds to S7025.

  In S7025, it is determined whether Ti detected in S7020 is less than a predetermined value Ti2 (> Ti1). If it is less than Ti2, the process proceeds to S7026, and if not, the process proceeds to S7028.

  When the process proceeds to S7023, the control circuit 30 returns the output P of the magnetron 12 to P1, and further sets the maximum preheating time tmax to tmax1 in S7024. The maximum preheating time is the time at which preheating is completed when this time has elapsed since the start of preheating, regardless of the temperature detected by the infrared sensor 7 at that time.

  When the process proceeds to S7026, the control circuit 30 returns the output P of the magnetron 12 to P2, and further sets the maximum preheating time tmax to tmax2 in S7027.

  When the process proceeds to S7028, the control circuit 30 returns the output P of the magnetron 12 to P3, and further sets the maximum preheating time tmax to tmax3 in S7029.

  Note that the output of the magnetron 12 is P1> P2> P3. Therefore, the output of the magnetron 12 is suppressed as the temperature of the inverter that is considered to have the largest temperature rise when the magnetron 12 is driven in the microwave oven 1 is higher.

  If ta is not counting, the output of the magnetron 12 is P1 when “Ti <Ti1”, and the output of the magnetron 12 is P2 “when Ti1 ≦ Ti <Ti2 or more”. On the other hand, if ta is counting, the output of the magnetron 12 is P2 in both cases. Therefore, in the present embodiment, if ta is being counted, the condition for changing the output of magnetron 12 is relaxed compared to when ta is not being counted, and the output of magnetron 12 is set as low as possible. Has been.

  Further, the maximum preheating time tmax1 to tmax3 can be set to different values. Thereby, in this Embodiment, the maximum preheating time can be determined according to the output of the magnetron 12. FIG.

  Referring to FIG. 39 again, next to the output setting A process in S702, the control circuit 30 causes the oven thermistor 59 to detect the temperature Tth in the heating chamber 10 in S703, and further outputs the preheat holding output Px. calculate. The preheating holding output Px is obtained according to the function f (x) of the preheating temperature x set in S3 or the like. Note that f (x) is predetermined. Since Px is an output for maintaining the temperature of the range baking dish 80, Px << P3 <P2 <P1.

  Next, in step S704, the control circuit 30 executes dish temperature detection processing. The detailed contents of the dish temperature detection process will be described with reference to FIG.

  In the dish temperature detection process, the control circuit 30 first moves each infrared detection element of the infrared sensor 7 to the initial position in S7041. Here, the temperature detection area by the infrared detection element in the infrared sensor 7 will be described.

  The infrared sensor 7 according to the present embodiment includes eight infrared detection elements. When each of the eight elements is an element n (n = 1 to 8), the temperature detection area ARn of the element n may be indicated as AR1 to AR8 on the range baking dish 80 as shown in FIG. it can. In FIG. 42, 8 × 16 intersection points when 8 lines A to H are drawn in the left-right direction and 16 lines 0 to 15 are drawn in the depth direction on the range baking dish 80. As shown, each of AR1 to AR8 includes 16 points in the depth direction. In the infrared sensor 7, scanning is performed so that the element n sequentially detects the temperatures of 16 points included in AR <b> 1 to AR <b> 8 and arranged in the depth direction. The initial position in S7041 is, for example, a position for detecting the temperature on the 0 line in the depth direction for each element.

  Referring to FIG. 41 again, next, in S7042, the control circuit 30 causes the infrared sensor 7 to scan so that each element detects the temperature at 16 points in each area of AR1 to AR8.

  Next, in S7043, the control circuit 30 calculates Tdave as an average temperature and Tnmax as a maximum temperature in the temperature detection at 16 points in S7042 of each element of the infrared sensor 7.

  In step S7044, it is determined whether or not an element to be subjected to preheating control is already determined among the eight infrared detection elements. This determination is performed in SA7, SA13, or SA14 described later. If it has already been determined, in S7045, an average temperature (Tcave) at each detected point of the target element is calculated, and the process returns. On the other hand, if no such element has been determined yet, the process returns.

  Referring to FIG. 39 again, after the processing of S704, the control circuit 30 calculates the Tdnave detected in the immediately preceding dish temperature detection processing in S705 as Tdnave0 (“n” includes 8 Since a number for recognizing one of the infrared detection elements is entered, Td1ave0 to Td8ave0 exist, and “0” is stored as the first scan).

  Next, in S706, the control circuit 30 determines whether or not Tth detected in S703 is less than a predetermined value Tth1, and if it is less than Tth1, the process proceeds to S707, and if Tth1 or more, the process is performed. The process proceeds to S708.

  In S707, the control circuit 30 determines whether or not the maximum value of Tdave0 is less than a predetermined value Tdave1. If it is less than Tdave1, the process proceeds to S709, and if it is equal to or greater than Tdave1, the process proceeds to S710. Proceed to

  On the other hand, in S708, the control circuit 30 determines whether or not the maximum value of Tdave0 is less than a predetermined value Tdave2, and if it is less than Tdave2, the process proceeds to S711, and if it is equal to or greater than Tdave1, the process is performed. Is advanced to S712.

  And control circuit 30 performs preheating control A processing, preheating control B processing, preheating control C processing, and preheating control D processing by S709, S710, S711, and S712, respectively, and returns.

  The contents of the preheating control A process will be described with reference to FIG.

  In the preheating control A process, first, the control circuit 30 determines whether the cooking menu currently operated in the microwave oven 1 is a menu stored in the lower stage (see FIG. 25) in the heating chamber 10 at SA1. Judging. In addition, in the microwave oven 1, the stage which should accommodate the microwave oven pan 80 can be shown with respect to a user for every cooking menu. If the menu is to be stored in the lower row, the process proceeds to SA2. If the menu is to be stored in the upper row, the process proceeds to SA14.

  In SA2, the control circuit 30 determines whether or not the latest maximum value of Tnmax is less than a predetermined value Tnmax1, and if it is less than Tnmax1, the process proceeds to SA3, and if it is greater than or equal to Tnmax1, SA13. Proceed with the process.

  In SA3, the control circuit 30 executes an output confirmation process. Here, the contents of the output confirmation processing will be described with reference to FIG.

  In the output confirmation process, the control circuit 30 first executes an output setting A process in SE1. The output setting A process is the process described with reference to FIG.

  Next, the control circuit 30 determines whether or not the output P of the magnetron 12 has been changed in the output setting A process executed immediately before, and if there is no change, returns directly. On the other hand, if there is a change, the process proceeds to SE3.

  In SE3, the control circuit 30 determines whether or not the output after the change is P3. If the output is P3, the control circuit 30 returns as it is. If the output is changed to other than P3, the process proceeds to SE4.

  In SE4, the control circuit 30 determines whether or not the preheating time tn has already been determined. If it has been determined, the process proceeds to SE5, and if it has not been determined, the process directly returns.

  In SE5, the control circuit 30 changes the preheating time tn according to the change in the output of the magnetron 12, and returns. Note that the preheating time tn after change (tn [after change]) is specifically the output of the magnetron 12 before and after change, the preheat time tn before change (tn [before change]), And it calculates using the count value of the timer t which started the count in S701.

  Referring to FIG. 43 again, when the output confirmation process in SA3 is completed, control circuit 30 next executes a dish temperature detection process in SA4. The dish temperature detection process is the process described with reference to FIG.

  Next, the control circuit 30 executes an error detection process at SA5.

  Here, the content of the error detection process will be described with reference to FIG.

  In the error detection process, first, at SF1, the control circuit 30 determines whether or not the count value of the timer t started counting at S701 is a predetermined value te1. If it is te1, the process proceeds to SF2, and if not, the process proceeds to SF6.

  In SF2, the control circuit 30 determines whether or not the output P of the magnetron 12 is P1. If it is P1, the process proceeds to SF3, and if it is not P1, the process proceeds to SF4.

  In SF4, the control circuit 30 determines whether or not the output P of the magnetron 12 is P2. If it is P2, the process proceeds to SF5, and if it is not P2, the process directly returns.

  In SF3, threshold values for determining that an error has occurred in the microwave oven 1 with respect to the temperature rise values ΔT1 and ΔT2 in the range pan 80 are set to Ta and Tb, respectively, and the process proceeds to SF11. In SF5, the threshold values for the temperature rise values ΔT1 and ΔT2 are set as Tc and Td, respectively, and the process proceeds to SF11. That is, here, the threshold value for the temperature rise value in the range baking dish 80, which is a criterion for determining the error, can be set to a different value according to the output of the magnetron 12.

  On the other hand, in SF6, it is determined whether or not the count value of the timer t is a predetermined value te2. If it is te2, the process proceeds to SF7, and if not, the process returns as it is.

  In SF6, the control circuit 30 determines whether or not the output P of the magnetron 12 is P1. If it is P1, the process proceeds to SF8, and if it is not P1, the process proceeds to SF9.

  In SF9, the control circuit 30 determines whether or not the output P of the magnetron 12 is P2. If it is P2, the process proceeds to SF10, and if it is not P2, the process directly returns.

  In SF8, thresholds for determining that an error has occurred in the microwave oven 1 with respect to the temperature rise values ΔT1 and ΔT2 in the range pan 80 are set as Te and Tf, respectively, and the process proceeds to SF11. In SF10, the thresholds for the temperature rise values ΔT1 and ΔT2 are set as Tg and Th, respectively, and the process proceeds to SF11. That is, also here, the threshold value for the temperature rise value in the range baking dish 80, which is a criterion for determining the error, can be set to a different value according to the output of the magnetron 12. Also, compared with the processing of SF3 and SF5, in this error detection processing, different threshold values are set depending on the processing time (te1 or te2).

  In SF11, the control circuit 30 determines whether or not the maximum value of “Tnmax−Tnmax0” is less than ΔT1. Note that “Tnmax−Tnmax0” is an increase value of the maximum value of the detection temperature of each infrared detection element from the maximum value of the first detection. Further, the maximum value of “Tnmax−Tnmax0” is the maximum value among the increased values of the eight elements.

  If the maximum value of “Tnmax−Tnmax0” is less than ΔT1, an error is notified at SF15 and the pre-heat treatment is stopped. Thereby, for example, when the temperature rise value of the range baking dish 80 is smaller than the expected range, or when each element of the infrared sensor 7 cannot normally detect the temperature, the pre-heat treatment can be stopped.

  On the other hand, when the maximum value of “Tnmax−Tnmax0” is equal to or greater than ΔT1, the control circuit 30 advances the process to SF12.

  In SF 12, the control circuit 30 determines whether or not the cooking menu operated in the microwave oven 1 is a menu for storing the range baking dish 80 in the lower stage of the heating chamber 10. If the menu is stored in the lower row, the process proceeds to SF13. If the menu is stored in the upper row, the process proceeds to SF14.

  In S13, the control circuit 30 determines whether or not the minimum value of “Tnmax−Tnmax0” is less than ΔT2. If the minimum value of “Tnmax−Tnmax0” is less than ΔT2, error notification is performed in SF15, the pre-heat treatment is stopped, and if it is equal to or greater than ΔT2, the process returns as it is.

  On the other hand, in S14, the control circuit 30 determines whether or not the minimum value of “Tnmax−Tnmax0” is equal to or greater than ΔT2. If the minimum value of “Tnmax−Tnmax0” is equal to or greater than ΔT2, error notification is performed in SF15 to stop the pre-heat treatment, and if it is less than ΔT2, the process returns.

  In the processes of SF12 to SF14 described above, the manner of determination to be an error differs depending on the height at which the range baking pan 80 is stored. This is because, as shown in FIG. 46, when the height at which the range baking dish 80 is stored is different, the area included in the visual field range QA of each infrared detection element of the infrared sensor 7 on the range baking dish 80 is different. It is. 46A shows a state where the range baking dish 80 is stored in the upper stage, and FIG. 46B shows a state where the range baking dish 80 is stored in the lower stage. When the range baking dish 80 is stored in the lower stage as shown in FIG. 46 (B), almost the entire area of the range baking dish 80 is included in the visual field range QA, but is stored in the upper stage as shown in FIG. 46 (A). If it does, the area | region which is not contained in the visual field range QA in the range baking dish 80 will increase. In SF14, it is determined whether or not the temperature detection by the infrared detection element can follow the temperature increase of the range baking dish 80 by determining whether or not the detection temperature of the infrared detection element is sufficiently increased. . And if it judges that it cannot follow, an error alert | report will be performed and pre-heat processing will be complete | finished.

  In the microwave oven 1, the scanning range of each infrared detection element can be changed by changing the angle of the infrared sensor 7 in accordance with the height at which the range pan 80 is stored in the heating chamber 10. preferable. In addition, when the preferred storage height of the range baking dish 80 is set for each cooking menu in the microwave oven 1, such a change in the scanning range is performed according to the selected cooking menu. Further, in the error detection process described above, when the storage position of the range baking dish 80 does not correspond to the scanning range of the infrared detection element, the temperature detection by the infrared detection element cannot follow the temperature rise of the range baking dish 80. An error notification is performed. That is, in the error detection process, the height at which the range baking dish 80 is stored can be detected by changing the scanning range, and the height of the range baking dish 80 is preferably set for each cooking menu. Even when it is not stored, error notification can be performed. In such a case, since error notification is performed, it is necessary for the user to recognize that there may be an error in the storage position of the range baking pan 80 for error notification.

  In the error detection process, if the temperature rise is not a predetermined degree, an error notification is performed. In addition, the aspect of temperature rise changes with the materials of the dish accommodated in the heating chamber 10. FIG. That is, in the error detection process, not only the storage position of the range baking dish 80 but also the material of the range baking dish 80 is normal, that is, the range baking dish 80 and other dishes are stored in the heating chamber 10 by mistake. Whether or not it is also subject to error notification.

  In addition, when the high-frequency heating element 81 is deposited only on a part of the range baking dish 80, it is preferable that the scanning range of the infrared detection element is only the region where the high-frequency heating element 81 is deposited. Thereby, temperature detection for a place where temperature detection is not necessary is omitted, and thus temperature detection by the infrared sensor 7 can be performed efficiently.

  Moreover, from the viewpoint of omitting temperature detection for a place where temperature detection is not necessary, the scanning range of the infrared detection element is preferably changed according to the cooking menu. For example, when performing stewed cooking, only the central part of the heating chamber 10 is scanned, or the temperature of the entire heating chamber 10 is detected at the start of heating, and the food placement position is determined. Only the placement position is scanned, or the user places the food placement position, and only the placement position is scanned.

  Referring to FIG. 43 again, in SA5 error detection processing, if pre-heat treatment is not stopped, control circuit 30 determines in SA6 whether the latest maximum value of Tnmax is equal to or greater than a predetermined value Tnmax2. If it is determined that Tnmax2 or more, the process proceeds to SA7, and if it is less than Tnmax2, the process returns to SA3.

  In SA7, the control circuit 30 calculates “Tnmax−Tdnave0” for the eight infrared detection elements, and removes the upper two and the lower two of the size, and the four infrared detection elements are subjected to the preheating control. The process proceeds to SA8 as the target element.

  On the other hand, in SA13, the control circuit 30 advances the process to SA8 with the element determined as the default A among the eight infrared detection elements as the target element for the preheating control. Thereby, for example, when it is difficult to determine a target element for preheating control due to, for example, the temperature of the microwave oven 80 being high from the beginning, a predetermined element is set as a target element for preheating control.

Further, the control circuit 30, the SA 14, in the eight infrared detection elements, the elements defined as the default B, as the target device of the preheating control, the process proceeds to SA8. As a result, as shown in FIG. 46A, an element considered to be appropriate when the range baking dish 80 is difficult to enter the field-of-view range QA of the infrared detection element is set as a target element for preheating control.

  In SA8, after executing the output confirmation process (see FIG. 44), the control circuit 30 executes the dish temperature detection process (see FIG. 41) in SA9, and executes the error detection process (see FIG. 45) in SA10. .

  If the pre-heat treatment is not stopped in the error detection process of SA10, the control circuit 30 determines that Tcave (average temperature within the scanning range detected by the target element for preheating control) is Tcave1 (predetermined temperature). ) Is reached. Then, the control circuit 30 repeats the processes of SA8 to SA10 until Tcave reaches Tcave1, and when Tcave reaches Tcave1, the process proceeds to SA12.

  In SA12, the timer ta starts counting, and the process proceeds to SA15.

  In SA15, the control circuit 30 executes the output confirmation process (see FIG. 44), then executes the dish temperature detection process (see FIG. 41) in SA16, and executes the error detection process (see FIG. 45) in SA17. .

  If the pre-heat treatment is not stopped in the error detection process of SA17, the control circuit 30 determines whether or not Tcave has reached Tcave2 (predetermined temperature) in SA18. Then, the control circuit 30 repeats the processes of SA15 to SA17 until Tcave reaches Tcave2. When Tcave reaches Tcave2, the control circuit 30 ends the count of the timer ta in SA19, determines the preheating time t1, and performs the process of SA20. Proceed to Note that the preheating time t1 is obtained from a function f2 (x, ta) of the preheating temperature x and the count value of the timer ta. Note that the function f2 (x, ta) is predetermined.

  In the present embodiment, since the preheating time t1 is obtained based on the function f2 (x, ta), it is not necessary for the infrared detecting element to detect the temperature up to a high temperature of the preheating temperature x, and the microwave oven 1 Cost reduction. The reason why t1 can be determined based on the preheat temperature x and the count value of ta will be described with reference to FIG.

  FIG. 47 is a diagram showing a time change of Tcave from the start of the preheat treatment. In addition, TM in FIG. 47 is an upper limit temperature at which the infrared detection element can perform temperature detection, and x is a preheating temperature. Tcave changes as indicated by the solid line.

  When preheating is started, Tcave rises to TM, and even if the temperature of the range baking pan 80 rises further, it becomes constant at Tcave. And the time t1 until the range baking pan 80 reaches the preheating temperature x can be assumed by assuming an extension line of the line extending from Tcave1 to Tcave2 (described by a one-dot broken line). In addition, as an example of each of x, TM, Tcave2, and Tcave1, 200 degreeC, 140 degreeC, 110 degreeC, and 70 degreeC are mentioned, for example.

  Referring to FIG. 43 again, after the process of SA19, control circuit 30 executes the output confirmation process (see FIG. 44) at SA20, and then at S21, the count value of timer t that has started counting at S701 The process of SA20 is executed until the count value reaches the preheating time t1 or the maximum preheating time tmax. When the count value reaches the preheating time t1 or the maximum preheating time tmax, the process returns.

  Next, details of the preheating control B process (FIG. 39) in S710 will be described with reference to FIG.

  In the preheating control B process, first, at SB1, the control circuit 30 sets the preheating time t2 to f3 (x) as a function of the preheating temperature x, and at SB2, the output of the magnetron 12 is set to the preheating holding output Px set at S703. In step SB3, output setting B processing is executed. Here, details of the output setting B process will be described with reference to FIG.

  In the output setting B process, the control circuit 30 first detects the inverter temperature Ti at SG1, and determines whether Ti is lower than Ti2 (predetermined temperature) at SG2. If Ti is less than Ti2, the process returns as it is. If Ti is equal to or greater than Ti2, the process returns at SG3 with the output P of the magnetron 12 set to P3 and the preheating time tn set to tmax3.

  Referring to FIG. 48 again, after the processing of SB3, control circuit 30 determines whether or not the count value of timer t that has started counting in S703 has reached preheating time t2. Then, the output setting B process of SB3 is executed until the count value of the timer t reaches the preheating time t2, and when the count value of the timer t reaches the preheating time t2, the process returns.

  In the preheating control B process described above, as shown in FIG. 39, when the temperature of the heating chamber 10 detected by the oven thermistor 59 is relatively low and the range baking dish 80 is relatively high. Since it is executed, the output of the magnetron 12 is lowered in the pre-heat treatment, and the content waits until the temperature of the range baking pan 80 naturally converges.

  Next, the detailed content of the preheating control C process performed by S711 is demonstrated with reference to FIG. In addition, the preheating control C process is a process executed when the temperature of the heating chamber 10 is relatively high and the temperature of the range baking dish 80 is relatively low as shown in FIG. . In the preheating control C process, the control circuit 30 first sets the preheating time t3 in SC1 based on the preheating temperature x and the function f4 (x, Tth) of the temperature of the heating chamber 10 detected by the oven thermistor 59, In SC2, an output confirmation process (see FIG. 44) is executed. Then, in SC3, the process of SC2 is repeated until the count value of the timer t reaches the preheating time t3. When the count value of the timer t reaches the preheating time t3, the process returns.

  Table 1 partially shows an example of the function f4 (x, Tth).

  f4 (x, Tth) defines a preheating time for each preheating temperature zone. Further, f4 (x, Tth) defines two temperature ranges of “Tth (low)” and “Tth (high)” using a predetermined threshold for the detected temperature Tth of the oven thermistor 59. Defines the preheating time.

  Next, details of the preheating control D process executed in S712 will be described with reference to FIG.

  In the preheating control D process, the control circuit 30 first sets the preheating time t4 in accordance with f5 (x) as a function of the preheating temperature x in SD1, sets the output of the magnetron 12 to P2 in SD2, and sets the output in SD3. The B process (see FIG. 49) is executed. Then, in SD4, the process of SD3 is repeated until the count value of the timer t reaches the preheating time t4, and when the count value of the timer t reaches the preheating time t4, the process returns.

  In the preheating described above, since the maximum preheating time is set, even if a defect occurs in the infrared detection element, the preheating is automatically terminated. Further, the number of elements to be subjected to preheating control is four of the eight infrared detection elements, but is not limited to this.

Further, in the preheating process of the present embodiment, when it is determined in S706 that the temperature of the heating chamber 10 detected by the oven thermistor 59 exceeds a predetermined temperature, the preheating control C process or the preheating control D process is performed. Control for driving the magnetron 12 for a predetermined time is performed. If it is determined in S706 that the temperature of the heating chamber 10 detected by the oven thermistor 59 is lower than a predetermined temperature, in S707, a process is selected according to the detection output of the infrared detection element of the infrared sensor 7. Has been made. In addition, the detection temperature of the oven thermistor 59 is a condition for branching from the preheating control A process to the preheating control D process. In each of the preheating control A process to the preheating control D process, the output of the magnetron 12 is It has been decided. For example, when the process proceeds to the preheating control D process, the output of the magnetron 12 is set to P2 unless the temperature of the inverter becomes equal to or higher than Ti2. Thus, in the present embodiment, the temperature of the heating chamber 10 is also a factor that determines the output of the magnetron 12.

  In the pre-heat treatment of the present embodiment, in S707 and S708, Tdnave0 (after the eight infrared detection elements of the infrared sensor 7 start heating by the magnetron 12, scanning for temperature detection in the heating chamber 10 is first performed. The maximum value of the temperature detected at the time of the comparison) is compared with a predetermined value (Tdave1 or Tdave2), and depending on the result, preheating time different in preheating control A to preheating control D in S709 to S712. Is set. That is, the preheating time is determined according to the temperature of the range baking dish 80 at a predetermined timing after the magnetron 12 oscillates the high frequency. Note that the temperature to be determined in S707 or S708 may be a temperature immediately before the magnetron 12 oscillates a high frequency, instead of the maximum value of Tdnave0.

  Next, details of the range baking cooking process (see FIG. 37) in S10 will be described with reference to FIG.

  In the range baking cooking process, the control circuit 30 first starts driving the magnetron 12 in S101, and waits for the cooking time of the first stage to elapse in S102. When the cooking time of the first stage has elapsed, in S103, the driving of the magnetron 12 is stopped, and a buzzer or the like notifies that the first stage has ended. At this time, as described above, the display unit 60 or the like presents an instruction to turn the food on the range baking dish 80 over.

  Then, the control circuit 30 waits for an operation for starting heating in S104, and resumes driving of the magnetron 12 in S105.

  The control circuit 30 waits for the cooking time of the second stage to elapse in S106. When the cooking time of the second stage elapses, the control circuit 30 stops driving the magnetron 12 and returns (S107).

  In the range-bake cooking process described above, the cooking time of the second stage, which is cooking after turning the food over, is made shorter than the cooking time of the first stage, which is cooking before turning over, in order to improve the finish of the food. It is preferable.

  Further, it is preferable to temporarily increase the output of the magnetron 12 immediately after the driving of the magnetron 12 is resumed in S105, that is, immediately after cooking of the second stage is started. This is because the magnetron 12 is temporarily stopped during the processes of S103 to S104, so that it is considered that the temperature of the heating chamber 10 and the range baking dish 80 is lowered.

  Further, during the execution of the range baking cooking process and the double-sided baking cooking process, the output of the magnetron 12 can be lowered when the temperature of the inverter becomes high, as in the preheating process. In addition, when the output of the magnetron 12 is reduced in the first stage, it is preferable to lengthen the cooking time of the second stage in order to compensate for the reduction in the output.

  Moreover, even when the microwave oven 1 is configured to reduce the output of the magnetron 12 when the temperature of the inverter becomes high and the condition for reducing the output is satisfied, the cooking time When there is little remaining, the output may not be reduced.

  Next, the details of the double-sided baking cooking process (see FIG. 38) in S26 will be described with reference to FIG.

  In the double-sided baking process, the control circuit 30 first drives the magnetron 12 in S261, and determines in S262 whether or not manual double-sided baking is currently selected. And if it is judged that manual double-sided baking cooking is selected, based on the cooking time set by S13 in S263, the cooking time of the 1st stage and the cooking time of the 2nd stage are predetermined. The process proceeds to S264. On the other hand, if it is determined in S262 that manual double-sided baking cooking is not selected, the process proceeds directly to S264.

  In S263, the cooking time of the first stage and the cooking time of the second stage are automatically determined, so that the user can perform an appropriate double-sided baking cooking process on the microwave oven 1 just by entering the entire cooking time. Can be executed.

  In S264, the process proceeds to S265 after waiting for the cooking time of the first stage to elapse. In S265, the driving of the magnetron 12 is stopped, and then the driving of the grill heater 51 is started. In step S267, the process proceeds to step S268 after waiting for the cooking time of the second stage to elapse.

  In S268, the drive of the grill heater 51 is stopped and the process returns.

  In the double-sided baking described above, the food on the range baking dish 80 is burnt on the upper surface by the grill heater 51, and the lower surface is burnt by the high-frequency heating element 81 of the range baking dish 80. By heating the inside of the food with high frequency, heating in a shorter time can be realized. It is better to drive the magnetron 12 and the grill heater 51 at the same time. However, due to the limitation of the maximum capacity of a general household outlet (breaker capacity is 15 to 20 A), high-frequency heating and heater heating are performed as in the above-described embodiment. And cooking is performed separately to realize cooking.

  In the heating chamber 10 of the microwave oven 1, when the installation position of the range baking dish 80 can be selected from a plurality of stages as shown in FIGS. In cooking in which the surface of the food is burnt by 51, it is preferable that the range baking dish 80 is installed at a position where the food is closest to the grill heater 51 as shown in FIG. And the control circuit 30 can display on the display part 60 that it instruct | indicates the installation position of the range baking pan 80 in this way.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a perspective view of the microwave oven which is one embodiment of the present invention. It is a front view of the operation panel of FIG. It is a front view of the state by which the door of the microwave oven of FIG. 1 was made into the open state. It is a perspective view of the microwave oven pan installed in the heating chamber of the microwave oven of FIG. It is a reverse view of the range baking dish of FIG. It is a front view of the range baking dish of FIG. It is arrow sectional drawing which follows the VII-VII line of FIG. It is arrow sectional drawing which follows the VIII-VIII line of FIG. It is a figure which shows typically the electric constitution of the microwave oven of FIG. It is a figure which shows the 1st modification of the heating chamber of the microwave oven of FIG. It is a figure which shows the 2nd modification of the heating chamber of the microwave oven of FIG. It is a figure which shows typically a cross section of the main-body part of the microwave oven of FIG. 11 in the height in which the convex part exists. It is a figure which shows typically a cross section of the main-body part of the microwave oven of FIG. 11 in the height in which the convex part exists. It is a figure which shows the 3rd modification of the heating chamber of the microwave oven of FIG. It is a figure which shows typically a cross section in the height in which the convex part exists of the main-body part of the microwave oven of FIG. It is a figure which shows typically a cross section in the height in which the convex part exists of the main-body part of the microwave oven of FIG. It is a figure for demonstrating the 4th modification of the microwave oven of FIG. It is a figure for demonstrating the effect of the other modification of FIG. It is arrow sectional drawing which follows the FF line | wire of FIG. It is a perspective view of the reflecting plate of FIG. It is a figure which shows the further modification of FIG. It is a figure which shows the further modification of FIG. It is a figure which shows the further modification of FIG. It is a figure which shows the further modification of FIG. It is a figure which shows the 5th modification of the microwave oven of FIG. In the microwave oven of FIG. 25, it is a figure which shows the temperature distribution on the range baking dish accommodated in the upper stage. In the microwave oven of FIG. 25, it is a figure which shows the temperature distribution on the range baking dish accommodated in the lower stage. FIG. 26 is a plan view of the rotating antenna of the microwave oven of FIG. 25. It is a figure which shows an example of the stop direction of the rotating antenna in the microwave oven of FIG. It is a figure which shows an example of the stop direction of the rotating antenna in the microwave oven of FIG. It is a reverse view of the range baking pan of the 6th modification of the microwave oven of FIG. It is a reverse view of the range baking pan of the 6th modification of the microwave oven of FIG. It is a reverse view of the range baking dish of the 7th modification of the microwave oven of FIG. It is arrow sectional drawing which follows the EE line | wire of FIG. It is a figure which shows the state which turned over the front and back of the range baking dish of FIG. In this Embodiment, when a microwave is supplied to a heating chamber, it is a figure which shows the relationship between the resistivity of a high frequency heat generating body, the electric field strength which a range baking dish reflects, and the electric field strength which permeate | transmits. It is a flowchart of the heat cooking process in the microwave oven of this Embodiment. It is a flowchart of the heat cooking process in the microwave oven of this Embodiment. FIG. 38 is a flowchart of a preheat treatment subroutine of FIG. 37. FIG. FIG. 40 is a flowchart of a subroutine of output setting A processing of FIG. 39. FIG. It is a flowchart of the subroutine of the temperature detection process of the plate of FIG. It is a figure for demonstrating the temperature detection range of each element of the infrared sensor of this Embodiment. It is a flowchart of the subroutine of the preheating control A process of FIG. 44 is a flowchart of a subroutine of output confirmation processing in FIG. 43. 44 is a flowchart of a subroutine for error detection processing in FIG. 43. It is a figure for demonstrating the change of the area included in the visual field range of an infrared rays detection element on a range pan according to the height in which a range pan is accommodated. It is a figure which shows the time change from the start of pre-heat processing of Tcave in the microwave oven 1. FIG. It is a flowchart of the subroutine of the preheating control B process of FIG. It is a flowchart of the subroutine of the output setting B process of FIG. It is a flowchart of the subroutine of the preheating control C process of FIG. It is a flowchart of the subroutine of the preheating control D process of FIG. It is a flowchart of the subroutine of the range baking cooking process of FIG. It is a flowchart of the subroutine of the double-sided baking cooking process of FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Microwave oven, 5 Main body frame, 6 Operation panel, 7 Infrared sensor, 9 Bottom plate, 10 Heating chamber, 12 Magnetron, 19 Waveguide, 40 Detection path member, 59 Oven thermistor, 80 Range baking dish, 81 High frequency heating element, 101, 102 Recess, 103, 104, 106, 107, 111-118 Rail.

Claims (2)

A heating chamber that accommodates an object to be heated , an infrared sensor that detects infrared rays in the heating chamber to detect temperature, a bottom plate that is provided on the bottom surface of the heating chamber and on which the object to be heated is placed, and oscillates high frequency A rotating antenna for supplying a high frequency from the magnetron supplied through the waveguide to the heating chamber while diffusing from the bottom surface of the heating chamber; An antenna accommodating portion that is disposed below the bottom plate and accommodates the rotating antenna; and a high-frequency heat generation that places the object to be heated and is accommodated in the heating chamber and absorbs the high frequency and generates heat on the back surface. Of the high frequency radiated from the rotating antenna, the heating pan in which the body is disposed, the rail formed on the left and right wall surfaces of the heating chamber and supporting the heating pan housed in the heating chamber In order to directly heat the object to be heated by the high frequency not absorbed by the high frequency heating element of the heating pan, the high frequency heating element provided between the high frequency heating element and the heating chamber wall surface is not absorbed by the high frequency heating element. Control for enabling the pre-heat treatment to control the driving of the magnetron based on the detection temperature of the infrared sensor and to heat the heating dish to a specific temperature based on the reaching path for reaching the high frequency above the heating dish. And comprising
The rotating antenna is disposed so as to overlap a high-frequency heating element of the heating dish housed in the heating chamber,
The controller is
In the pre-heat treatment, based on the detection temperature of the heating dish detected by the infrared sensor immediately before driving the magnetron or the detection temperature of the heating dish detected by the infrared sensor at the start of driving the magnetron Then, the driving time of the magnetron for raising the temperature of the heating dish to a specific temperature is determined . A heating chamber that accommodates an object to be heated, an infrared sensor that detects infrared rays in the heating chamber to detect temperature, a bottom plate that is provided on the bottom surface of the heating chamber and on which the object to be heated is placed, and oscillates high frequency A rotating antenna for supplying a high frequency from the magnetron supplied through the waveguide to the heating chamber while diffusing from the bottom surface of the heating chamber; An antenna accommodating portion that is disposed below the bottom plate and accommodates the rotating antenna; and a high-frequency heat generation that places the object to be heated and is accommodated in the heating chamber and absorbs the high frequency and generates heat on the back surface. Of the high frequency radiated from the rotating antenna, the heating pan in which the body is disposed, the rail formed on the left and right wall surfaces of the heating chamber and supporting the heating pan housed in the heating chamber In order to directly heat the object to be heated by the high frequency not absorbed by the high frequency heating element of the heating pan, the high frequency heating element provided between the high frequency heating element and the heating chamber wall surface is not absorbed by the high frequency heating element. A path for reaching the upper side of the heating dish and a control for controlling the driving of the magnetron based on the temperature detected by the infrared sensor and performing pre-heat treatment for heating the heating dish to a specific temperature. And comprising
The rotating antenna has a portion that overlaps a high-frequency heating element of the heating dish housed in the heating chamber,
The controller is
In the pre-heat treatment, based on the detection temperature of the heating dish detected by the infrared sensor immediately before driving the magnetron or the detection temperature of the heating dish detected by the infrared sensor at the start of driving the magnetron Then, the driving time of the magnetron for raising the temperature of the heating dish to a specific temperature is determined .

Images