JP2001304564A - High frequency heating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high frequency heating device for use in heating a heated item such as a food in which a finished temperature of the food can be made uniform by its simple constitution. SOLUTION: A distribution of temperature of a heated item 1 placed on a food mounting table 28 which can be driven to rotate is detected through a plurality of openings of a heating chamber 8 under an application of an infrared ray sensor 13 having a plurality of infrared ray sensor elements and a lens 19 having a plurality of lens functions and then a high temperature position and a low temperature position can be acknowledged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-frequency heating apparatus for automatically heating an object to be heated such as food by detecting the temperature of the object to be heated.

[0002]

2. Description of the Related Art As shown in FIG. 4, a conventional heating device comprises a cooking means for cooking food 2 in a heating chamber 1 and a heating chamber 1 in a non-contact manner as described in, for example, Japanese Patent Application Laid-Open No. 6-193883. A food temperature detecting means 4 for detecting the temperature of the food 2 through the opening 3 provided in the apparatus, a detecting position driving means 5 for changing the temperature detecting position of the food temperature detecting means 4, and a closing means 6 for closing the opening 3 And a control means for setting the closing means 6 to an active state when the food temperature detecting means 4 is inactive. The detecting position driving means 5 drives the closing means 6, so that the food temperature detecting means 4 The temperature information of a plurality of places crossing the food is measured simultaneously and in parallel, the driving means 5 moves the temperature detecting means 4 so as to cross the food 2 and performs reciprocal scanning, and the food is rotated every time the turntable 7 makes one or half rotation. , Plate, turntable, etc. surface temperature Fabric is obtained as a two-dimensional thermal image information.

[0003] Of the two-dimensional thermal image obtained by the food temperature detecting means, a portion where the temperature rises remarkably due to cooking is regarded as a food portion, and the temperature unevenness state of the extracted food, the average temperature of the food, and the like are determined. By adjusting the output of the cooking means in accordance with the changing temperature state of the food, automatic cooking can be performed without variation in the workmanship, and when the food temperature detecting means 5 is in the inactive state, the detection position driving means 5 is closed by the closing means. To protect the food temperature detecting means 4 from steam and splashes generated from the food for closing the opening of the food storage.

[0004]

However, in the conventional configuration, the detection position driving means 5 for changing the temperature detection position of the temperature detection means 4 is required. In this configuration, the surface temperature distribution of the food 2 is obtained as a two-dimensional thermal image. However, when trying to determine the uneven heating of the food, the detection position of the temperature detection means 4 is driven in synchronization with the rotation of the turntable 3 accurately. Therefore, there is a problem that a high-precision mechanism is required and the cost is high. Further, the detection position driving means 5 is required, and further, it is necessary to provide a space so as not to hinder the change in the position of the temperature detection means 4, and the outer dimensions of the heating device become large in order to obtain a two-dimensional thermal image. There was also the problem of getting lost.

An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a heating device which can obtain a two-dimensional thermal image at a low cost and a small external size and can also improve uneven heating.

[0006]

A temperature detecting means comprising a plurality of infrared sensor elements for detecting radiation of infrared energy from a plurality of portions of the object to be heated,
A two-dimensional thermal image can be obtained without driving the temperature detecting means by employing a configuration in which infrared energy from a plurality of locations on the object to be heated is focused on the plurality of infrared sensor elements by a plurality of lenses. Therefore, the accuracy of the detection position can be increased, the configuration can be realized at a low cost, and it can be realized very compact, and the outer shape of the high frequency generator can be reduced.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to a first aspect of the present invention is directed to a heating chamber for storing an object to be heated, a high-frequency generator for supplying high-frequency radio waves to the heating chamber, and infrared rays from a plurality of portions of the object to be heated. Temperature detecting means for detecting the temperature of the object to be heated, which is constituted by a plurality of infrared sensor elements for detecting the radiation of energy, wherein infrared energy from a plurality of locations on the object to be heated is detected by a plurality of lenses. Light was condensed on the infrared sensor element.

Thus, a two-dimensional thermal image can be obtained without driving the temperature detecting means. Therefore, the accuracy of the detection position can be increased, the configuration can be realized at a low cost, and it can be realized very compact, and the outer shape of the high frequency generator can be reduced.

In the invention according to claim 2, the lens has a plurality of lens functions integrally formed. Thereby, the relative position of each lens function is fixed, and the temperature at a plurality of locations on the object to be heated can be detected with high positional accuracy without any variation in the position during assembly.

Further, in the invention according to claim 3, the heating chamber is provided with a plurality of openings for transmitting infrared rays from a plurality of places of the object to be heated. As a result, if infrared rays from a plurality of locations are transmitted through one opening, the size of the opening must be increased, but the size of each opening is reduced by dispersing and transmitting the infrared light through the plurality of openings. can do.

Therefore, the leakage of high-frequency radio waves can be reduced, and the influence of noise due to high-frequency radio waves can be suppressed.
Food temperature can be accurately detected.

[0012]

An embodiment of the present invention will be described below with reference to the drawings. The same components as those of the conventional example are denoted by the same reference numerals.

FIG. 1 is a sectional view of a main part of a high-frequency heating apparatus according to an embodiment of the present invention. FIG. 2 is an enlarged sectional view of a main part of the temperature detecting means of the present invention. FIG. 3 is a schematic view of the high-frequency heating device of the present invention.

In FIG. 1, two openings 9 are provided on the side of the heating chamber 8. Temperature detecting means 1 facing the opening
0 is provided. The case 11 of the temperature detecting means 10 is made of metal or plated resin.
A printed board 12 is built in the case 11, and an infrared sensor 13 for detecting infrared rays from food and an amplifier 14 for amplifying a signal of the infrared sensor 13 are provided on the printed board 12.
Is provided. A lens 19 made of resin or the like is provided so as to cover the infrared sensor 13. The lens 19 has two lens functions and includes a lens A20 and a lens B21. A shutter plate 22 is provided in the vicinity of the lens 19, and opens and closes an opening 23 provided in the case 11 so that infrared rays radiated from the object 1 can reach the infrared sensor 13 or be blocked. Control. The shutter plate 22 is driven by a motor 24.

In FIG. 2, four infrared sensor elements 15, 16, 17, 18 are provided inside the infrared sensor 13. A window 25 made of silicon or the like that transmits infrared light is provided on the upper surface of the infrared sensor, and the infrared sensor 13 is sealed. The infrared sensor 13 is covered by a lens 19. Lens 19 has lens A2
0 and the lens B21 are integrally formed. Heated object 1
The infrared light from the lens passes through two openings 9 provided in the heating chamber 8, and the infrared light transmitted through one of the openings 9-1 is transmitted through the lens A2.
Infrared rays transmitted through the aperture 0 and condensed on the infrared sensor elements 15 and 16 and passed through the other opening 9-2 are transmitted through the lens B21 and condensed on the infrared sensor elements 17 and 18. A partition 26 made of a material that does not transmit infrared light is provided between the lens A20 and the lens B21,
The infrared light transmitted through the lens A20 is transmitted to the infrared sensors 17, 1
8 so that the infrared rays transmitted through the lens A21 are not focused on the infrared sensors 15 and 16. If the infrared sensor is a pyroelectric infrared sensor, the temperature difference between the shutter plate 22 and the object 1 can be detected as an output, and the temperature of the shutter plate 22 can be detected by the temperature sensor 27. Thus, the temperature of the object to be heated 1 can be detected. In the case of a thermocouple type infrared sensor, the temperature difference between the hot junction and the cold junction, which receives infrared rays from the object 1 to be heated, can be detected as an output. The temperature of the object 1 can be detected. The shutter plate 22 opens and closes the opening 23, and also serves to protect the temperature detecting means 10 by closing the opening 23 when the temperature detecting means 10 does not operate.

In FIG. 3, the object to be heated 1 stored in the heating chamber 8 is placed on the food placing table 28 and
Is configured to be rotated by the driving device 29. A high-frequency generator 30 is coupled to the heating chamber 8 to supply high-frequency radio waves to the inside of the heating chamber 8 to heat the object 1 to be heated. The temperature detecting means 10 is disposed above the power supply port 31 for high-frequency radio waves, detects temperatures at four points on the approximate radius of the food placing table 28, and rotates the food placing table 28 so that two points on the food placing table 28 rotate.
A two-dimensional thermal image is obtained. The signal of the temperature detecting means 10 is input to the control means 32 and controls the driving device 29 and the high frequency generator 30.

With such a configuration, the temperature detecting means 10
Thus, a two-dimensional thermal image on the food table 28 can be obtained without driving the device, and a compact and inexpensive configuration can be achieved. Further, since a plurality of lens functions are integrally formed, the accuracy of the relative position of each lens function is increased, and the accuracy of a two-dimensional thermal image is enhanced. In addition, the size of each opening can be reduced by dispersing the infrared rays from the object to be heated 1 and dispersing and condensing the infrared rays from the object to be heated 1 with a plurality of openings 9 provided in the heating chamber 8, thereby reducing the leakage of high-frequency radio waves. Can be smaller.

In this embodiment, the number of infrared sensor elements is four. The number of elements is not limited to four as described below, and may be larger, for example, six. At this time, similarly, the lens C may be provided as a set of two elements to have the same configuration. Also, one set of three elements may be used. In this case, however, further consideration is required with respect to position detection accuracy and leakage of high-frequency radio waves.

Next, the operation and the operation will be described. The temperature detecting means 10 detects infrared rays and the like from four points on the radius of the food placing table 28, and if the food placing table 28 makes one rotation, the temperature detecting means 10 detects the infrared ray. It is possible to detect infrared rays from almost the entire surface, and it is possible to detect a temperature distribution during heating of the article to be heated 1 placed on the food table 28. The control means 32 can detect the highest temperature position and the lowest temperature position of the heated object 1 based on the detected signal of the temperature distribution of the heated object 1, and determine the temperature difference between the highest temperature position and the lowest temperature position. When the temperature becomes equal to or higher than the temperature, the driving device 29 of the food placing table 28 is controlled so as to stop when the position of the lowest temperature of the article 1 to be heated comes to a position where the electric field intensity is predetermined at the highest. Normally, the electric field intensity is strongest in the vicinity of the power supply port 31, and the position of the lowest temperature of the object to be heated 1 is stopped near the power supply port 31. At this time, if the temperature detecting means 10 is disposed above the power supply port 31, the temperature detecting means 10 can detect a rise in the temperature of the object 1 to be stopped.

As a result, the position of the lowest temperature of the object to be heated 1 can be heated more strongly, so that the temperature difference of each part of the object to be heated can be reduced, and the object to be heated can be more uniformly heated.

In the embodiment, the infrared sensor has four sensors.
Although the elements have been described, the invention is not limited to this, and the number of elements can be increased or decreased according to the size of the food table 28 and the required resolution of the thermal image. . For example, if the temperature measurement range of one infrared sensor element is larger than the range of a circle having a diameter of 3 cm, the accuracy of temperature identification decreases, and the error increases.
Further, if the range is narrowed, the accuracy is improved but the cost is increased. Usually the radius of the food table of the high frequency heating device is 15cm
In order to measure the temperature of the entire radius, five infrared sensor elements are required, but about four are practical except for the center and the end. As described above, the number of elements is equal to the number of the present embodiment. It doesn't matter.

[0022]

According to the present invention, a heating chamber for accommodating an object to be heated, a high-frequency generator for supplying a high-frequency electric wave to the heating chamber, and a plurality of infrared sensors for detecting radiation of infrared energy from a plurality of portions of the object to be heated. Temperature detecting means for detecting the temperature of the object to be heated constituted by elements, and infrared light energy from a plurality of locations of the object to be heated is condensed on the plurality of infrared sensor elements by a plurality of lenses. .

Thus, a two-dimensional thermal image can be obtained without driving the temperature detecting means. Therefore, the accuracy of the detection position can be increased, the configuration can be realized at a low cost, and it can be realized very compact, and the outer shape of the high frequency generator can be reduced.

The lens has a plurality of lens functions integrated. Thereby, the relative position of each lens function is fixed, and the temperature at a plurality of locations on the object to be heated can be detected with high positional accuracy without any variation in the position during assembly.

The heating chamber is provided with a plurality of openings for transmitting infrared rays from a plurality of places on the object to be heated. As a result, the size of the opening has to be enlarged if infrared light from multiple locations is transmitted to one opening,
By dispersing and transmitting the light through a plurality of openings, the size of each opening can be reduced.

Therefore, it is possible to reduce the leakage of the high-frequency radio wave, to suppress the influence of the noise by the high-frequency radio wave,
Food temperature can be accurately detected.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a high-frequency heating device according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a main part of a temperature detecting means of the high-frequency heating device.

FIG. 3 is a schematic diagram of the high-frequency heating device.

FIG. 4 is a block diagram of a conventional heating device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heated object 8 Heating chamber 9 Opening 10 Temperature detecting means 13 Infrared sensor 15, 16, 17, 18 Infrared sensor element 19 Lens

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Kazuo Fujishita 1006 Kadoma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Takahiko Yamazaki 1006 Kadoma Kadoma Kadoma City, Osaka Matsushita Electric Industrial F Term (Reference) 3K086 AA01 AA07 BA02 BA08 BB02 CA04 CA15 CB04 CB06 CB12 CB15 CC01 CC06 CD11 CD19 FA07 FA08 3K090 AA01 AB02 BA01 BB01 DA01 EA01 EB02 EB16 FA01 3L086 AA02 AA04 BA06 BB02 CB17 DA06 CB07 DA06

Claims (3)

[Claims] A heating chamber for accommodating an object to be heated; and a temperature detecting means comprising a plurality of infrared sensor elements for detecting radiation of infrared energy from a plurality of points of the object to be heated, A high-frequency heating apparatus wherein the detecting means is configured to focus infrared energy from a plurality of locations on the object to be heated to the plurality of infrared sensor elements by a plurality of lenses. 2. The high-frequency heating device according to claim 1, wherein the lens has a plurality of lens functions integrally formed. 3. The high-frequency heating apparatus according to claim 1, wherein the heating chamber is provided with a plurality of openings for transmitting infrared rays from a plurality of places on the object to be heated.