JP2017067325A - Heating cooker - Google Patents

Abstract

A cooking device capable of appropriately heating an object to be heated is provided.
A range heating means, a weight sensor, an infrared sensor, an input means, and a control means for calculating a heating time of an object to be heated are provided. The control means is based on detection results of the weight sensor and the infrared sensor. Determine whether the initial temperature of the object to be heated is frozen, refrigerated or normal temperature, and if the initial temperature is determined to be frozen, detection from the weight sensor at an earlier time after the start of heating than when refrigerated or normal temperature is determined The heating time obtained from the result is corrected, and the remaining time until the end of heating displayed on the display unit is corrected.
[Selection] Figure 11

Description

  The present invention relates to a cooking device, and more particularly to a cooking device including an infrared sensor for measuring the temperature of an object to be heated (food) that is heated in a heating chamber.

  In the known technology known in Patent Document 1, the weight of tableware to be used is tared, the weight of only the food to be heated and the initial temperature of the food are detected, the state of the food is determined to be frozen, refrigerated, and normal temperature. The heating time and heating output determined based on the weight of the food are corrected according to the temperature state of the food.

JP 2010-112634 A

  In the heating cooker shown in Patent Document 1, it is necessary to measure and register the weight of tableware. In addition, it is necessary to be careful not to mistake the registered tableware with the tableware used for heating. For this reason, there is a problem that much labor is required.

  The present invention has been made in order to solve the above-described problems, and includes a heating chamber that houses an object to be heated and a container in which the object to be heated is stored, a magnetron that heats the object to be heated, and an electric power to the magnetron. A range heating means comprising an inverter circuit for supplying the table, a table plate provided at the bottom of the heating chamber on which the object to be heated and the container are placed, and a table plate that supports the table plate and is placed on the table plate A weight sensor that detects the total weight of the heated object and the container, an infrared sensor that is provided above the heating chamber and detects the temperature of the heated object in a non-contact manner, and the heating means are selected. An input unit having an operation unit for inputting heating conditions, a display unit for displaying the content input from the operation unit and the progress of cooking, and the weight sensor in response to an input from the input unit. Control means for calculating the heating time of the object to be heated from the detection result of the infrared sensor and controlling the range heating means, the control means being based on the detection results of the weight sensor and the infrared sensor. It is determined whether the initial temperature of the heated object is frozen, refrigerated or normal temperature, and when the initial temperature is determined to be frozen, detection from the weight sensor at an earlier time after the start of heating than when it is determined that the temperature is refrigerated or normal temperature The heating time obtained from the result is corrected, and the remaining time until the end of heating displayed on the display unit is corrected.

  ADVANTAGE OF THE INVENTION According to this invention, the heating cooker which can heat a to-be-heated material appropriately is provided.

The front perspective view of the heating cooker which concerns on the Example of this invention. The rear perspective view which removed the outer frame of the cooking-by-heating machine concerning the example of the present invention. AA sectional drawing of FIG. Operation | movement explanatory drawing of the infrared sensor which uses FIG. 3 sectional drawing. The enlarged view for description of the infrared sensor part which shows a reference position. The enlarged view for description of the infrared sensor which shows an end point position. The enlarged view for description of the infrared sensor which shows the state which closed the observation window. The flowchart figure for determining the basic heating time of the normal temperature / refrigeration mode and freezing mode which concerns on the Example of this invention. Explanatory drawing explaining the heating operation of the heating cooker which concerns on the Example of this invention. The control block diagram explaining control of the heating time of the heating cooker. Explanatory drawing explaining the weight correction | amendment of the reference | standard heating time of the heating cooker. Explanatory drawing explaining the visual field of the infrared sensor of the heating cooker. Explanatory drawing of the theory which calculates the heating time of the heating cooker which concerns on the Example of this invention.

Embodiments of the present invention will be described below with reference to the drawings.
1 is a perspective view of the main body of the heating cooker as viewed from the front side, FIG. 2 is a perspective view of the main body as viewed from the rear side with the outer frame removed, and FIG. 3 is a cross-sectional view taken along line AA in FIG. .

  In the figure, the main body 1 of the heating cooker puts food to be heated in a heating chamber 28, and cooks the food using microwaves, the heat of the heater, and superheated steam.

The door 2 is opened and closed to put food in and out of the heating chamber 28. By closing the door 2, the heating chamber 28 is hermetically sealed to prevent leakage of microwaves used when heating the food, The heater heat and superheated steam are contained to enable efficient heating.
The handle 9 is attached to the door 2 and facilitates opening and closing of the door 2, and has a shape that can be easily grasped by a hand.
The glass window 3 is attached to the door 2 so that the state of the food being cooked can be confirmed, and uses glass that can withstand high temperatures due to heat generated by a heater or the like.

The input means 71 is provided on the operation panel 4 below the front surface of the door 2, and includes an operation unit 6 for inputting heating means such as microwave heating and heater heating, a heating time, and a heating temperature, and an operation unit 6. It is comprised with the display part 5 which displays the content input from 1 and the progress state of cooking.
The outer frame 7 is a cabinet that covers the upper surface and the left and right side surfaces of the main body 1 of the heating cooker.

  The water tank 42 is a container for storing water necessary for producing superheated steam, and is provided on the lower front side of the main body 1 of the heating cooker, and is configured to be detachable from the front surface of the main body 1 to supply water. And drainage can be done easily.

  The rear plate 10 forms the rear surface of the cabinet described above, and an external exhaust duct 18 is attached to the upper part of the rear plate 10, and cooling air (waste heat) after cooling the steam discharged from the food and the internal components of the main body 1 is cooled. 39 is discharged from the external exhaust port 8 of the external exhaust duct 18.

The machine room 20 is provided in a space between the heating chamber bottom surface 28a and the bottom plate 21 of the main body 1, and a magnetron 33 for heating food on the bottom plate 21, a waveguide 47 connected to the magnetron 33, A control board 23 on which the control means 23a (see FIG. 10) is mounted, other various components described later, a fan device 15 for cooling these various components, and the like are attached.
The bottom surface 28a of the heating chamber has a concave shape in the substantially central portion, and the rotating antenna 26 is installed therein, and the microwave energy radiated from the magnetron 33 passes through the waveguide 47 and the output shaft 46a of the rotating antenna 26 penetrates. The air flows into the lower surface of the rotating antenna 26 through the opening 47a, and is diffused by the rotating antenna 26 and radiated into the heating chamber 28. The output shaft 46 a of the rotating antenna 26 is connected to the rotating antenna driving means 46.

  The fan device 15 includes a cooling fan attached to a cooling motor attached to the bottom plate 21. The cooling air 39 generated by the fan device 15 cools the self-heating magnetron 33, the inverter circuit (not shown), the back side weight sensor 25c, the left side weight sensor 25b, and the like in the machine room 20. Further, it flows between the outside of the heating chamber 28 and the outer frame 7 and between the hot air case 11a and the rear plate 10 as described above, and cools the outer frame 7 and the rear plate 10 while cooling the outer frame 7 and the rear plate 10 with the external exhaust port 8 of the external exhaust duct 18. More discharged. Further, a duct 16a for cooling the hot air motor 13 described later and a duct 16b for cooling the infrared unit 50 housed in an infrared case 48 described later are provided, and the cooling air 39 for cooling the infrared unit 50 is After being discharged from the opposite side of the exhaust duct 28e that discards the exhaust heat (such as water vapor) in the heating chamber 28, it is discharged outside from the external exhaust duct 18.

  The range heating means 330 (see FIG. 10) includes a magnetron 33 and an inverter circuit (not shown), and is controlled by the control means 23a.

  A hot air unit 11 is attached to the rear of the heating chamber 28, and a hot air fan 32 that efficiently circulates the air in the heating chamber 28 is attached in the hot air unit 11. A hot air intake hole 31 and a hot air blowing hole 30 are provided.

  The hot air fan 32 rotates by driving a hot air motor 13 attached to the outside of the hot air case 11 a and heats the air circulating in the hot air heater 14.

  Further, the hot air unit 11 is provided with a hot air case 11a on the rear side of the heating chamber inner wall surface 28b, and the hot air heater 14 is positioned between the heating chamber inner wall surface 28b and the hot air case 11a so as to be positioned on the outer peripheral side thereof. The hot air motor 13 is attached to the rear side of the hot air case 11a, and the motor shaft is connected to the hot air fan 32 through a hole provided in the hot air case 11a.

  Since the hot air motor 13 rises in temperature due to heat from the heating chamber 28 and the hot air heater 14, in order to prevent this, the hot air motor 13 is surrounded by a hot air motor cover 17 and formed in a substantially cylindrical shape, and the duct 16 a is connected to the hot air case 11 a and the rear plate 10. The upper end opening of the duct 16a is connected to the lower surface of the hot air motor cover 17, the lower end opening is connected to the outlet of the fan device 15, and a part of the cooling air 39 from the fan device 15 is connected. The hot air motor cover 17 is incorporated.

  On the back side of the heating chamber top surface 28c of the heating chamber 28, a grill heating means 12 made of a heater is attached. The grill heating means 12 is formed in a flat shape by winding a heater wire around a mica plate, and pressing and fixing the mica plate against the back side of the top surface of the heating chamber 28 to heat the top surface of the heating chamber 28 so that the food in the heating chamber 28 is It is baked by radiant heat.

  Further, an infrared unit 50 described later is provided on the back side of the heating chamber top surface 28c of the heating chamber 28. The infrared unit 50 is covered with an infrared case 48 to cool the infrared unit 50, and is formed in a substantially cylindrical shape so that the duct 16b is formed. Located between the hot air case 11 a and the rear plate 10, the upper end opening of the duct 16 b is connected to the side surface of the infrared case 48, the lower end opening is connected to the upper surface of the hot air motor cover 17, and cooling air from the fan device 15 is connected. Part of 39 is taken in.

  A heating chamber temperature sensor 80 for detecting the heating chamber temperature TH1 of the atmosphere of the heating chamber 28 by a thermistor is provided on the left back side of the heating chamber top surface 28c of the heating chamber 28.

The heating chamber bottom surface 28a is provided with a plurality of weight sensors 25, for example, a left weight sensor 25b on the front left and right, a right weight sensor (not shown), and a back weight sensor 25c in the rear center, on which a table is placed. A plate 24 is placed.
The table plate 24 is used for placing food, and is formed of a material having heat resistance and good microwave permeability so that it can be used for both heater heating and microwave heating. Further, a flange portion 24b (including the rising wall 24a) is provided around the periphery for easy holding. Further, by providing the flange portion 24b (including the rising wall 24a), even if a drink is spilled when the heated object is taken in and out during heating, the dirt remains on the table plate 24 and can be easily cleaned afterwards.

  The boiler 43 is attached to the outer surface of the hot air case 11a of the hot air unit 11 so that the saturated water vapor faces the hot air unit 11, and the saturated water vapor ejected into the hot air unit 11 is heated by the hot air heater 14 to become superheated water vapor.

  The pump means 87 pumps the water in the water tank 42 to the boiler 43, and is composed of a pump and a motor that drives the pump. The adjustment of the amount of water supplied to the boiler 43 is determined by the ON / OFF ratio of the motor.

  The heating means is a range heating means 330, a hot air heater 14, a hot air motor 13, a grill heating means 12, a boiler 43, and the like.

  Next, details of the infrared sensor that detects the temperature of the object to be heated in a non-contact manner provided above the heating chamber 28 will be described with reference to FIGS. 4 to 7.

  A motor 51 is attached so that the direction of the motor 51 is parallel to the rotating shaft 51a and the heating chamber inner wall surface 28b. The rotating shaft 51a rotates (drives) a cylindrical unit case 54, which will be described later, thereby rotating the substrate 53 mounted with the infrared sensor 52 housed in the unit case 54 so that the direction of the lens portion 52a of the infrared sensor 52 is changed. The temperature can be detected by rotating the range from the back side of the heating chamber bottom surface 28a (the heating chamber back wall surface 28b side) to the heating chamber opening 28d. As the motor 51, a stepping motor is used, and the rotation shaft 51a can be rotated forward and backward, and the rotation angle can be operated as desired by the control of the control means 23a provided on the control board 23.

  An infrared sensor 52 is provided with a plurality of infrared detection elements (for example, thermopiles). Here, an infrared sensor in which eight elements are aligned in a line in the vertical direction of the rotation shaft 51a is used. Therefore, it is possible to detect the temperature at the plurality of locations at the same time in the left-right direction of the heating chamber bottom surface 28a, and an infrared sensor extends from the back side (heating chamber back wall surface 28b side) to the front side (door 2 side) of the heating chamber 28. By rotating 52, the entire area of the heating chamber bottom surface 28a is divided into a plurality of parts to detect the temperature. Specifically, the temperature of the entire surface of the table plate 24 placed on the heating chamber bottom surface 28a is detected.

  The infrared sensor 52 is provided at substantially the center in the left-right direction of the heating chamber top surface 28c inside the virtual line extending vertically from the four sides of the table plate 24 placed on the heating chamber bottom surface 28a to the heating chamber top surface 28c. Yes.

  The field of view of the infrared sensor 52 is roughly defined as a detection point a and a detection point h in a range in which the temperature of the flange portion 24b before and after the table plate 24 is detected. It is substantially defined in a range in which the temperature of the left and right flange portions 24b of the plate 24 is detected. By doing so, it becomes possible to accurately detect the temperature of the object to be heated 60c placed substantially at the center of the table plate 24.

  Reference numeral 54 denotes a cylindrical unit case, which is provided with a window portion 54a on which the substrate 53 is disposed at the maximum diameter portion so that the lens portion 52a of the infrared sensor 52 faces. In addition, carbon is included in the material of the unit case 54 to make the characteristic of the unit case 54 a conductive material, thereby preventing the entry of external noise into the unit case 54.

  Reference numeral 55 denotes a shutter made of a metal plate. The shutter 55 closes an observation window 44a described later when the infrared sensor 52 is not used (see FIG. 7). Further, in order to prevent the temperature of the heating chamber 28 from being transmitted to the unit case 53, an air passage 55 c having a gap along the outer periphery of the unit case 54 is formed so that cooling air can flow on the outer periphery of the unit case 53. A shutter 55 is disposed in the air passage 55c, and an opening 55a and an opening 55b are provided in the air passage 55c to serve as an inlet / outlet for the cooling air 39 to flow.

  Reference numeral 56 denotes a positioning convex portion, and when the control unit controls the rotation of the motor 51 so that the detection point of the infrared sensor 52 is aligned with the reference position (detection point a in FIG. 4), the reference position of the detection point of the infrared sensor 52 When the observation window 44a is closed by the shutter 55, the rotation shaft 51a is slipped in a state where the positioning projection 56 is in contact with a stopper (not shown) provided in the infrared case 48, The reference position controlled by the control unit and the position of the detection point a serving as the reference position detected by the infrared sensor 52 can be corrected.

  Reference numeral 44 denotes an arc-shaped observation portion that is discharged inward of the heating chamber 28, and is provided along the rotation center of the rotating shaft 51a, the center of the cylindrical unit case 54, and the outer periphery of the unit case 54, and is bent into an arc shape. The center of the arc of the shutter 55 and the center position of the arc-shaped observation unit 44 are all the same position. An observation window 44 a is provided in the observation unit 44 and opens a range that is a visual field range detected by the infrared sensor 52. Further, in order to prevent microwave leakage from the observation window 44a during microwave heating, a standing wall (burring) 44b is provided on the outer periphery of the observation window 44a by about 2 mm.

  By projecting the observation unit 44 to the inside of the heating chamber 28, it is possible to detect a wide range of temperatures within a minimum narrow observation window opening range.

  49 is a convex part, which separates the infrared case 48 and the infrared unit 50 from the heating chamber top surface 28c. By making only the convex part 49 contact with the heating chamber top surface 28c, the grill heating means 12 and hot air are heated. The temperature of the heating chamber top surface 28 c heated by a heater such as the unit 11 is not easily transmitted to the infrared unit 50.

The measurement procedure of the infrared sensor 52 of the control means 23a mounted on the control board 23 will be described.
The infrared sensor 52 is a sensor that measures 8 points in one measurement, and the motor 51 moves the infrared sensor 52 from the reference position (FIG. 4, detection point a) to the end point position (FIG. 4, detection point h) 14 times three times. Then, the measurement is performed in a total of 15 rows by rotating.

  Then, 120 temperatures of 8 points in the left-right direction × 15 rows in the front-rear direction are detected. From the end point position to the reference position, the infrared sensor 52 returns directly to the reference position without measuring. Processing of the measured temperature will be described later.

Next, the rotational movement of the infrared sensor 52 will be described.
As an example of a container 60 opened at the top containing an object to be heated (milk) 60c, when a cup is placed on the table plate 24 provided on the heating chamber bottom surface 28a and heating is started, the magnetron 33 stably transmits. For 1 to 2 seconds, the observation window 44 a is closed by the shutter 55 (see FIG. 7) to prevent noise due to unstable transmission at the start of transmission of the magnetron 33 from entering the infrared sensor 52.

  After the transmission of the magnetron 33 is stabilized, the control means 23a controls the rotating shaft 51a of the motor 51 to rotate to the reference position. As the rotary shaft 51a rotates to the reference position, the unit case 54 rotates, and the direction of the lens portion 52a of the infrared sensor 52 also rotates to a position where the detection point a at the reference position can be detected. At this time, the cooling air 39 flows through the lens portion 52a of the infrared sensor 52 and flows from the observation window 44a to the heating chamber 28, thereby preventing dirt from adhering to the lens portion 52a.

  By rotating the unit case 54, the detection of the temperature of the heated object 60c proceeds from the reference position (detection point a) to the detection point b and detection point c of the table plate 24, and when the unit case 54 further rotates. The temperature outside the cup (container 60) is detected in the height direction, and the temperature from the detection point d to the detection point e is detected. After the detection point reaches the top of the opening of the cup (container 60), the temperature of the surface of the object 60c to be heated is detected at the detection point f, and then the temperature inside the cup (container 60) is detected at the detection point g. Then, the temperature of the table plate 24 is detected at the end point of the detection point h.

  The temperature in the temperature detection range from the detection point a to the detection point h is detected on one of the forward paths rotating the unit case 54. After detecting the temperature to the end point once, the temperature is detected without measuring the return path on the way. Instead, the detection point a to the detection point h are sequentially performed again after returning to the reference position again.

  The number of detected temperatures is changed according to preference, and the detection points a to h described above are illustrative examples, and 15 rows of data are measured as described above.

  The temperature is detected by stopping the rotation of the motor 51 while the temperature is detected, and rotating after the detection. In order to detect the temperature accurately, it is better to stop and measure.

  For example, at the beginning of heating, the rotation of the unit case 54 is stopped and detected. After the detection, the rotation is performed at a certain angle, the rotation is stopped and detected, and the rotation is performed at a certain angle after the detection is repeated. Measure the temperature distribution. By doing so, the entire surface of the table plate 24 in the heating chamber 28 is measured evenly by measuring the temperature at a constant position at an equal angle.

  With this setting, when the cup (container 60) is placed on the back side of the table plate 24, the temperature of the object to be heated 60c in the cup can be detected at the detection point b substantially below the infrared sensor 50. When the cup (container 60) is placed on one of the left and right sides of the table plate 24, the infrared sensor 52 is provided at the approximate center in the horizontal direction of the heating chamber 28, and therefore is provided in the infrared sensor 52. The temperature of the object to be heated 60c can be detected by the infrared sensors on both sides of the eight elements arranged in a line.

  Further, when the weight information is light and the temperature rise of the temperature distribution is recognized over a wide range from the weight information by the weight sensor 25 and the temperature distribution information detected by the infrared sensor 52, it can be determined that the heated object 60c is thin and wide. Further, when the weight information is heavy and the temperature rise of the temperature distribution is recognized only in a narrow range, it can be determined that the object to be heated 60c is placed in a tall cup (container 60), for example.

  In the present embodiment, the infrared unit 50 is provided on the heating chamber top surface 28c, but the infrared unit 50 is installed on the basis of the same idea described above even when the infrared unit 50 is installed on the front side of the heating chamber top surface 28c. Thus, the temperature of the object to be heated 60c can be accurately detected.

  In the present embodiment, the method for detecting the temperature of the heated object 60c placed in the cup 60 has been described in detail. However, even when the heated object 60c that does not use a container is a block-shaped large lump, Since the temperature of the side surface height direction and the upper surface of the object 60c can be detected, the temperature distribution of the object to be heated 60c can be detected in detail.

Next, processing of the temperature measured by the infrared sensor 52 of the control means 23a will be described.
First, a problem when the temperature of the object to be heated 60c is detected using the infrared sensor 52 will be described.
The infrared sensor 52 has different detection temperatures due to the difference in emissivity even when the temperature of the heated object 60c is the same. In addition, since the data output from one infrared sensor 52 is output as the temperature of the object to be measured within the field of view of the infrared sensor 52 as a substantially average value, the object to be measured (the object to be heated) and the table within the field of view. When the plate 24 is provided, an average value of the temperature corresponding to each area of the object to be measured (object to be heated) and the table plate 24 is output.

  The former emissivity difference is set according to a menu that can be input by the input means 71, thereby enabling appropriate correction.

Next, the temperature detection of the latter to-be-heated object 60c is demonstrated in detail.
As described above, the infrared sensor 52 has a plurality of (for example, eight elements) infrared sensors 52 arranged in a row so that the approximate size and outer shape of the object 60c can be recognized. A total of 120 (8 × 15) temperature data are acquired in the table 24 by measuring the temperature in 15 rows by moving 14 times.

  The acquired 120 pieces of temperature data are arranged as shown in FIG. Each of the 120 squares shown in the figure is called a pixel. This pixel is set at a viewing angle having 50% or more of the directivity characteristic of the infrared sensor 52. However, the output from the infrared sensor 52 includes the following which are all measured objects included in the field of view (viewing angle 100%). A pixel having a viewing angle having 50% or more of the directivity, a plurality of pixels adjacent to the pixel, and a wall surface of the heating chamber 28 other than the table plate 24 are also included. Therefore, it is necessary to substantially calculate the temperature of the heated object 60c by correcting the detected temperature.

  In the present embodiment, the latter problem (temperature detection of the object to be heated 60c) of the infrared sensor 52 described above will be described in detail. Information necessary for the correction is the temperature of the wall surface of the table plate 24 and the heating chamber 28, the recognition (determination) of the heated object 60c, and the temperature of the heated object 60c determined as the size of the heated object 60c.

  The temperature of the wall surface of the table plate 24 and the heating chamber 28 which is the necessary information described above will be described. In the heating cooker, the table plate 24 is used in a state in which it is always placed in the heating chamber 28. Therefore, by detecting the temperature of the table plate 24, the temperature of the wall surface can be recognized as the same. If the difference between the temperature detected using the heating chamber temperature sensor 80 and the temperature of the table plate 24 detected by the infrared sensor 52 is large, the temperature may be corrected as a separate temperature.

  For detecting the temperature of the table plate 24, the temperature of the flange 24b (including the rising wall 24a) of the table plate 24 is detected and used as the temperature of the table plate 24. Since the object to be heated 60c and the like cannot be placed on the flange portion 24b (including the rising wall 24a), the temperature of the table plate 24 can be accurately detected. The temperature of the 42 pixels on the outer periphery shown in FIG. 12 is the place where the temperature of the table plate 24 is detected.

Next, the recognition and size of the heated object 60c and the recognized temperature of the heated object 60c will be described.
Recognition of the to-be-heated object 60c determines the pixel which has a specific temperature difference with respect to the temperature of the table plate 24 mentioned above as the to-be-heated object 60c. However, since the object to be heated 60c has a wide range of temperatures such as freezing, refrigeration, and room temperature, the following determination method is used for recognizing the object to be heated 60c.

  Since the cooking device is mainly placed in the kitchen, it becomes the same temperature as normal temperature except immediately after being used for heating.

  When the object to be heated is frozen or refrigerated, the temperature of the object to be heated 60c is lower than the temperature of the table plate 24. In order to accurately recognize the object to be heated 60c, it is determined that the object to be heated 60c has been recognized when the detected minimum temperature of each pixel is a specific temperature lower than the temperature of the table plate 24. The size of the object to be heated 60c is a collection of pixels indicating the temperature included in the temperature range confirmed in advance corresponding to the difference between the minimum temperature and the temperature of the table plate 24 from the minimum temperature. Recognized as the size of the object to be heated 60c. The minimum temperature is recognized as the temperature of the object to be heated 60c, and the detected temperature of the object to be heated 60c is calculated and derived by calculating the initial temperature of the true object to be heated 60c by correction described later.

  When the object to be heated 60c is higher than the temperature of the table plate 24, the object to be heated is detected when the detected maximum temperature of each pixel is higher than the temperature of the table plate 24 in order to accurately recognize the object to be heated 60c. It is determined that 60c has been recognized. The size of the object to be heated 60c is a collection of pixels indicating the temperature included in the temperature range confirmed in advance corresponding to the difference between the maximum temperature and the temperature of the table plate 24 from the maximum temperature. Recognized as the size of the object to be heated 60c. Then, the maximum temperature is recognized as the temperature of the object to be heated 60c, and the detected temperature of the object to be heated 60c is calculated and derived by calculating the initial temperature of the true object to be heated 60c by correction described later.

  When the object to be heated 60c is normal temperature, the temperature of the table plate 24 is equal to the temperature of the object to be heated 60c. Therefore, a specific temperature difference is required between the detected temperature of each pixel and the temperature of the table plate 24. This is the case. Specifically, determination is made on either side of the above-described specific temperature difference assuming that the heated object 60c is frozen or refrigerated, or assuming that the heated object 60c is higher than the temperature of the table plate 24. If not, the entire area of the table plate 24 is recognized as the object to be heated 60c. And by heating the to-be-heated object 60c and raising the temperature, the pixel temperature at the position where this rise has risen above a specific temperature is recognized as the detected temperature of the to-be-heated object 60c, and the detected temperature of the to-be-heated object 60c is detected. Is derived by calculating the initial temperature of the true object to be heated 60c by correction described later.

Next, a correction method will be described.
The correction is to correct the detected temperature of the heated object 60c from the temperature of the table plate 24 recognized above and the size of the heated object 60c.

  In the correction method, the temperature of the detected table plate 24 was confirmed in advance by the room temperature correction temperature obtained by performing a specific arithmetic process confirmed in advance and the number of pixels indicating the size of the detected heated object 60c. A heating region correction temperature obtained by performing a specific calculation process is obtained, and a corrected initial temperature Sf that is a true initial temperature of the object to be heated 60c is derived by a calculation process to the detected temperature of the object to be heated 60c. . However, with regard to the temperature of the table plate 24, in consideration of actual use, the detected result is higher than the set maximum temperature with respect to the maximum temperature and the minimum temperature in the usable environmental temperature range set by the product. In this case, the set maximum temperature is set as the maximum temperature value, and if the detected result is lower than the set minimum temperature, the set minimum temperature is set as the minimum temperature value. The temperature is corrected in advance. Further, the number of pixels indicating the size of the detected heated object 60c is also within a range that assumes the size of the heated object 60c from the amount of the heated heated object 60c described in the instruction manual. If the number of detected pixels exceeds the maximum value, it is corrected in advance to the assumed maximum value, and the number of detected pixels is less than the minimum value. In this case, correction is made in advance to the assumed minimum value. By doing so, even when unexpected heating is performed, it is corrected to a range that can protect the safety of the user.

  Next, a method for controlling the temperature of the object to be heated 60c using both the infrared sensor 52 and the weight sensor 25 will be described with reference to FIGS. In the above description, the heated object 60c is described as milk and the container 60 is a cup. However, in the following description, the heated object 60c is described as rice and the container 60 is described as a tea bowl.

  First, the relationship between the initial temperature of the heated object 60c to be heated and the heating time for heating will be briefly described. In the input means 71, an appropriate menu for heating the article to be heated 60c is selected and set. This is because the difference in dielectric characteristics (dielectric constant, dielectric power factor) due to the difference in the object to be heated 60c varies the degree of heating by the microwave. Further, the difference in emissivity due to the difference in the object to be heated 60c is applied to the correction of the detection temperature of the infrared sensor 52.

  Further, as a major factor affecting the degree of heating, the weight of the object to be heated 60c and the initial temperature can be mentioned. Generally, the difference in the degree of heating due to the difference in weight is such that the smaller the weight, the harder it is to heat, and the dielectric characteristics (dielectric constant, dielectric power factor) differ depending on the temperature of the heated object 60c. It is.

  The heating time is such that the heavier the object to be heated 60c, the longer the time required for heating to a specific temperature, and the lower the initial temperature of the object to be heated 60c, the longer the time required to heat to a specific temperature. become longer. For example, when the temperature of the object to be heated 60c is −3 ° C. or lower, as shown in FIG. 13, when heating to the final set temperature, the defrost time (T1) and the melting time (T2) and the time (T3) The total heating time is required.

  For example, when heating rice, when heating from freezing, the heating time TR is the sum of T1 + T2 + T3. In normal temperature storage, the heating time TJ is only T3.

  FIG. 10 is a control block diagram for explaining the control of the heating time. When a key is input from the input means 71 to the control means 23a to determine the menu and start, the heating chamber temperature sensor 80, the infrared sensor 52, and the weight sensor are input. 25, the heating operation of the range heating means 330 is started. The heating time is determined by correcting the heating time based on detection results from the infrared sensor 52 and the weight sensor 25.

  FIG. 8 is a flowchart for heating an object to be heated using an infrared sensor and a weight sensor.

A container 60 containing rice to be heated 60c is placed on the table plate 24 in the heating chamber 28, and the door 3 is closed. A menu is selected by the input means 71 (S0).
The finish adjustment is selected by the input means 71 (S1). A start is input by the input means 71 (S2). The control means 23a determines the heating output P of the heating means corresponding to the selected menu. (S3).

  Next, the control means 23a detects the total weight W of the heated object 60c and the container 60 placed on the table plate 24 by the weight sensor 25 (S4). About the weight of the container 60, the same weight as the to-be-heated material 60c is assumed.

  Next, the control means 23a detects the heating chamber temperature TH1 by the heating chamber temperature sensor 80 (S5). When the temperature of the heating chamber is higher than a predetermined value, the heating time (reference total heating time Tz) is calculated and controlled based on the value of the weight W detected by the weight sensor 25 without using the infrared sensor 52. . When the temperature of the heating chamber 28 is lower than a predetermined value, the heating time is controlled based on the weight W detected by the weight sensor 25 and the temperature information detected by the infrared sensor 52. At this time, a corrected initial temperature Sf, which is a true initial temperature of the object to be heated 60c corrected by the above-described method based on the temperature information detected by the infrared sensor 52, is obtained (S6).

  Range heating is started with the incorporated output (for example, 700 W) (S7).

  It is determined whether the corrected initial temperature Sf, which is the initial temperature of the object to be heated 60c determined by the correction, is higher than a specific temperature (for example, −2 ° C.) (S8).

  (S8) is switching of the heating mode, and when the corrected initial temperature Sf, which is the initial temperature of the heated object 60c obtained by correction, is higher than a specific temperature (yes), the heating mode is shifted to the normal temperature / refrigerated mode. Then, the heating time is calculated, and the object to be heated 60c is heated to the set temperature (S9). When it is low in (S8) (No), the heating mode is shifted to the refrigeration mode, the heating time is calculated, and the object to be heated 60c is heated to the set temperature (S10).

  Next, as the heating time calculated in the room temperature / refrigeration mode or the freezing mode, a basic total heating time Tz confirmed in advance required for heating to a set temperature (for example, 85 ° C.) is calculated.

  As described above, when it is determined to be frozen according to the input heating conditions, an intermediate determination temperature (for example, 40 ° C.) is set to a lower temperature than when it is determined to be refrigerated or normal temperature, and the intermediate from the start of heating. A reference heating time α1 until the determination temperature is reached is calculated and set.

  Then, when it is determined to be refrigerated or normal temperature in accordance with the input heating conditions, a midway determination temperature (for example, 60 ° C.) is set, and a reference heating time α1 from the start of heating until reaching the midway determination temperature is calculated. To set.

  The reference total heating time Tz and the reference heating time α1 are based on the corrected initial temperature Sf, which is the initial temperature of the heated object 60c obtained by correction, the dielectric characteristics affecting the degree of heating, the detected weight W, and the like. This is the time required to heat up to the preset temperature and the mid-term determination temperature that can be confirmed in advance. However, the midway determination temperature is set to be equal to or lower than the upper limit temperature that can be detected by the infrared sensor 52. Here, the temperature is set to 60 ° C. or lower, which is lower than the temperature at which water vapor is generated from the object to be heated 60c.

  Further, when it is determined that the temperature is frozen at the corrected initial temperature Sf, the midway determination temperature is set to a lower temperature than when the temperature is determined to be refrigerated or normal temperature. In this case, when heating is performed after freezing, the speed of temperature rise differs depending on the location with respect to time, and heating unevenness is likely to occur depending on the object to be heated 60c. The portion where the absorption of microwaves is improved by partial thawing becomes faster at the temperature rise, and the portion to be heated 60c is defrosted to become liquid, or the portion that touches and does not touch the liquid. The speed of temperature rise differs and temperature unevenness occurs. Therefore, when heating from freezing, how fast is the temperature rise of the heated object 60c with respect to the heating at the midway determination temperature provided at a lower temperature than when refrigerated or heated from room temperature, and the calculated heating time Is to check whether it is appropriate. That is, the heating time to be corrected is increased in the heating time until the finishing temperature is reached, and the heating from the freezing is performed to the just right temperature. Furthermore, in the case of refrigeration, there is a high probability of correcting the heating time for the reason described above, so the heating time is corrected early to inform the user of the end time.

  The midway determination temperature is set to a different temperature in accordance with the heating condition in which the menu input by the input means 71 or the food to be heated is selected. In the menu with a low finishing temperature, the mid-term determination temperature is naturally set to a low temperature. In this way, by using the information on the weight W by the weight sensor 25 instead of only the temperature information detected by the infrared sensor 52, heating can be performed in consideration of the small amount of the object 60c to be heated.

  The reason why the heating mode is divided into freezing and normal temperature / refrigeration according to the corrected initial temperature Sf of the heated object 60c is that the dielectric properties (dielectric constant, dielectric power factor) of the heated object 60c (rice) are in the freezing temperature range. This is because the change is greatly different between normal temperature / refrigerated temperature zones. Moreover, you may divide into three, frozen, refrigerated, and normal temperature. Furthermore, although the corrected initial temperature Sf is described as being replaced with a state (freezing, refrigeration, normal temperature), it may be expressed in a temperature range of any ° C to what ° C. Further, a database of a reference total heating time Tz (described later) obtained from a corrected initial temperature Sf and weight W corrected according to the object to be heated 60c is created, and a corrected initial temperature Sf and weight which are corrected initial temperatures are created. The reference total heating time Tz may be directly derived from W.

  With respect to the heating time obtained in the freezing and normal temperature / refrigeration modes, the temperature of the object to be heated 60c is detected from the start of heating by the infrared sensor 52, and the corrected initial temperature Sf is obtained by correcting the temperature. When the temperature of the pixel at the same position as the pixel that has been reached reaches the midway determination temperature, it is determined whether the elapsed time from the start of heating is earlier or slower than the reference heating time α1 described above. The final heating time is calculated by correcting the reference total heating time Tz obtained above.

  For example, when the elapsed time is earlier than the reference heating time α1, such as β1, in this case, it is determined that the breakdown of the detected weight is less than the weight of the container 60, and the elapsed time β1 The total heating time for reaching the set temperature is calculated by correcting the reference total heating time Tz so as to prevent overheating of the rice.

  When the elapsed time is later than the reference heating time α1 such as γ1, it is determined that the breakdown of the detected weight is larger than the weight of the container 60, and the reference total heating time Tz is determined from the elapsed time γ1. The total heating time to reach the set temperature is calculated with a long correction to prevent the rice from being overheated.

  When the elapsed time is substantially the same as the reference heating time α1, it is determined that the detected weight breakdown is substantially the same as the weight of the container 60 and the weight of the rice, and the total heating for reaching the reference total heating time Tz to the set temperature. Continue heating at the time determined. When the difference between the elapsed time and the reference heating time α1 is within 10% of the reference heating time α1, heating is continued for the reference total heating time Tz without correction. This 10% is an allowable value that does not adversely affect the result of heating. The total heating time obtained by the correction is obtained from the ratio of the reference total heating time Tz, the reference heating time α1, and the elapsed time.

  Moreover, when the microwave output from the magnetron 33 becomes weak after many years of use, the temperature rise of the heated object 60c at the time of heating is delayed, and the elapsed time to reach the above-described midway determination temperature is delayed. Therefore, by correcting the reference total heating time Tz from the elapsed time from the start of heating to obtain the total heating time, the heating temperature of the object to be heated 60c can be kept constant to some extent.

  This mid-term determination temperature is an example determined as the temperature before the water vapor comes out of the rice to be heated, the upper limit temperature that can be detected by the infrared sensor.

  If possible, the temperature of the rice is always detected using the infrared sensor 52, and it is sufficient that the heating can be terminated when the detected temperature detects the set temperature of 85 ° C. However, when the rice is heated and water vapor is generated, the infrared sensor 52 There is a problem that the temperature of the rice cannot be detected accurately due to the influence of. Therefore, an intermediate determination temperature is set, and the temperature rise of the heated rice is detected until reaching the intermediate determination temperature, and when this is reached, the reference total heating time Tz as described above is corrected to determine the total heating time and the rice is heated. I have time to manage.

  And the content displayed on the display part 5 can notify a user the timing which a heating is complete | finished by displaying the remaining time until the temperature of the to-be-heated material 60c reaches preset temperature.

  The displayed remaining time is the time elapsed from the reference total heating time Tz to the determination of the reference total heating time Tz when the reference total heating time Tz is calculated by switching to the room temperature / refrigeration mode or the freezing mode. The time obtained by subtracting the time is displayed as the remaining time until the end of heating, and the remaining time is displayed by operating the subtraction timer from the displayed time. When the temperature of the object to be heated 60c reaches the midway determination temperature and the total heating time is determined, the remaining time obtained by subtracting the elapsed time from the determined total heating time is displayed again as the remaining time until the end of heating. A person can be informed of a certain heating end time. Therefore, the remaining time may increase or decrease when the remaining time until the end of heating is redisplayed according to the weight ratio of the container 60 and rice used during heating.

  In this heating apparatus, time is used as a reference used for control from the result detected by the weight sensor 25 and the result detected from the infrared sensor 52 to the end of heating, so that correction of the heating time during heating is facilitated. Yes. In addition, the user can easily know the timing of the end of heating.

  When the infrared sensor 52 breaks down or the lens portion 52a becomes dirty and the temperature of the heated object 60c cannot be detected, the heating time based on the weight W detected by the weight sensor 25 is calculated as backup control, It is also possible to manage the heating time as the total heating time. This control is the same as the heating control when the temperature of the heating chamber 28 is higher than the predetermined temperature.

  Then, after detecting the midway determination temperature by the infrared sensor 52, the observation window 44a is closed by the shutter 55 of the infrared sensor 52, so that the heated object that occurs at the time of occurrence of bumping due to the abnormal temperature rise of the heated object 60c should occur. The lens portion 52a is prevented from being contaminated by the scattered matter of the object 60c.

  In this way, the temperature detected by the infrared sensor 52 is used as the corrected initial temperature Sf, and the reference total heating time Tz is calculated using the weight W detected by the weight sensor 25, so that the room temperature is high or low. Even if the temperature of the object to be heated 60c is normal temperature, refrigeration, or freezing, the rice can be heated to just the preferred temperature without being affected by the large amount of the heated part 60c.

  According to the above-described embodiment, it is possible to provide a cooking device capable of appropriately heating the heated object 60c while suppressing the influence of the temperature of the heated object 60c and suppressing the influence of the weight of the container.

DESCRIPTION OF SYMBOLS 1 Main body 6 Operation part 5 Display part 23a Control means 24 Table plate 25 Weight sensor 28 Heating chamber 33 Magnetron 52 Infrared sensor 60 Container 60c Heated object 71 Input means 330 Range heating means Sf Correction | amendment initial temperature W Weight (alpha) 1 Reference | standard heating time

Claims (1)

A heating chamber for storing an object to be heated and a container for storing the object to be heated;
A range heating means including a magnetron for heating the object to be heated, and an inverter circuit for supplying electric power to the magnetron;
A table plate on the bottom of the heating chamber, on which the object to be heated and the container are placed;
A weight sensor that supports the table plate and detects the total weight of the object to be heated and the container placed on the table plate;
An infrared sensor provided above the heating chamber to detect the temperature of the object to be heated in a non-contact manner;
An operation unit that selects the heating unit and inputs a heating condition; and an input unit that includes a display unit that displays an input content from the operation unit and a cooking progress state;
Control means for calculating a heating time of the object to be heated from detection results of the weight sensor and the infrared sensor according to an input from the input means, and controlling the range heating means,
The control means determines whether the initial temperature of the object to be heated is frozen, refrigerated, or normal temperature from the detection results of the weight sensor and the infrared sensor, and when the initial temperature is determined to be frozen, Correcting the heating time obtained from the detection result from the weight sensor at an earlier time after the start of heating than when determined, and correcting the remaining time until the end of heating displayed on the display unit, To cook.

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