JPH07320858A - High-frequency heating device - Google Patents

Abstract

PURPOSE:To provide a high-frequency heating device having an automatic cooking function covering a wide weight range of foodstuff as a cooking object. CONSTITUTION:Two microwave detection means 2 having different sensitivity are provided in a heating chamber, and the reflection of microwave energy substantially different due to the wide weight range of a foodstuff 7 is detected with microwave sensors 8 and 12 having sensitivity suitable for the strength of the reflection. According to this construction, foodstuff weight over a wide range can be discriminated, and the foodstuff 7 over a wide weight range can be automatically cooked.

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 device.

[0002]

2. Description of the Related Art Conventionally, for automatic cooking such as thawing, 1
Although there is a means for estimating the food weight using two detection sensors and performing automatic cooking using the correlation between the food weight and the cooking time, the food weight that can be estimated is only up to about 1 kg.

A conventional example will be described below with reference to the drawings.
As shown in FIG. 4, the microwave is oscillated by the magnetron 2 in the heating chamber 1 for heating the food. Part of the microwave is absorbed by the food in the heating chamber and part of it is reflected. This amount of reflection is detected by the microwave detection sensor 3.
The output voltage obtained from the microwave detection sensor 3 is integrated through the integrating circuit 4 and input to the microcomputer 5, and the microcomputer 5 calculates an output voltage corresponding value. The food weight is estimated by the correlation between the output voltage corresponding value and the food weight shown in FIG. 2, and the estimated food weight is used to determine the heating time from the correlation between the food weight and the heating time.

[0004]

However, in this configuration, the amount of microwave energy reflected from the food in the heating chamber is extremely reduced in a large weight food, and as shown in FIG. The correlation between the output voltage corresponding value and the output voltage is no longer established, and the weight of food cannot be determined in a large weight range.

Further, even if the sensitivity of the microwave detection sensor 3 is increased to detect the extremely reduced microwave energy, the microwave energy in a small amount of food becomes extremely large. For this reason, the output voltage of the microwave detection sensor 3 becomes constant at the maximum input value of the microcomputer in the integrating circuit 4 before entering the microcomputer 5, and the weight cannot be determined in the small food weight range. . That is, there is a problem in that it is not possible to accurately grasp the amount of reflection of microwave energy that greatly differs from foods having a wide range of weight, and it is not possible to determine the weight of a wide range.

[0006] Therefore, an object of the present invention is to provide a high-frequency heating device capable of performing a wide range of weight discrimination and automatically cooking food having a wide range of weights.

[0007]

In order to achieve the first object, the present invention provides two microwave detecting means having different sensitivities.

In order to achieve the second object, the present invention is to install two microwave detecting means having the same sensitivity on the wall surface of the heating chamber at different distances.

[0009]

In the high frequency heating apparatus of the present invention, the two microwave detecting means having different sensitivities using the microwave detecting sensor as the microwave detecting means are provided, so that the reflection amount of the microwave energy which is greatly different can be accurately grasped. Therefore, the weight of a wide range of foods can be determined.

Further, by mounting two microwave detecting sensors having the same sensitivity on the wall surface of the heating chamber at different distances, two microwave detecting means requiring different sensitivities can be easily obtained by the microwave detecting sensors having the same sensitivity. realizable.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A case where a microwave detecting sensor is used as a microwave detecting means in a high frequency heating apparatus according to an embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, the microwave excited by the magnetron 2 is guided into the heating chamber 1 by the waveguide 6, and is mostly absorbed by the food 7 and partially reflected. A high-sensitivity microwave detection sensor (hereinafter referred to as a high-sensitivity detection sensor) 8 is attached to the ceiling of the heating chamber 1 at a right angle to the first hole 9. Further, a low-sensitivity microwave detection sensor (hereinafter referred to as a low-sensitivity detection sensor) 12 is attached to the side surface of the heating chamber 1 at a right angle to the second hole 13. The food 7 is placed on a turntable 10 for uniform heating, and the turntable 10 is rotated by a turntable motor 11.

The output voltage obtained from the high-sensitivity detection sensor 8 passes through the integrating circuit 4 and is input to the microcomputer 5 to be calculated as a first output voltage corresponding value. The output voltage obtained from the low-sensitivity detection sensor 12 passes through the integrating circuit 4 and is input to the microcomputer 5 to be calculated as a second output voltage corresponding value. In FIG. 2, when the first output voltage corresponding value is higher than the threshold value C, the driving time of the high voltage power supply 14 for driving the magnetron 2 is determined from the correlation between the first output voltage corresponding value and the food weight. It When the first output voltage corresponding value is lower than the threshold value C, the driving time of the high voltage power supply 14 for driving the magnetron 2 is determined from the correlation between the second output voltage corresponding value and the food weight.

In the present embodiment, when the food weight is small, there is strong microwave reflection, so the low-sensitivity detection sensor 12
It is possible to obtain a correlation between the first output voltage corresponding value obtained from Eq. Further, when the weight of the food is large, there is weak microwave reflection, so that the correlation between the second output voltage corresponding value obtained from the high-sensitivity detection sensor 8 and the weight of the food can be obtained.

By capturing the microwave energy that greatly changes depending on the weight of the food with a detection sensor having a sensitivity suitable for its strength, it is possible to distinguish the weight of the food over a wide range and automatically cook foods over a wide range of weight. Become.

Next, an embodiment in which two microwave detecting means which require different sensitivities are realized by using microwave detecting sensors having the same sensitivity will be described with reference to FIG. Heating chamber 1
The first microwave detection sensor 15 is provided on the ceiling of the
It is attached to the hole 9 by the first metal fitting 17 at a distance a from the outer wall surface of the ceiling portion. Further, a second microwave detection sensor 16 is provided in the second hole 13 on the side surface of the heating chamber 1.
It is attached by the metal fitting 18 at a distance b from the outer wall surface of the side surface. First microwave detection sensor 15
The second microwave detection sensor 16 and the second microwave detection sensor 16 have the same sensitivity. Further, in this embodiment, the distance a is about half the distance b.

In the present embodiment, the first microwave detection sensor 15 and the second microwave detection sensor 16 have the same sensitivity, but the distance a is about half the distance b, so the first microwave detection sensor The intensity of the microwave reaching 15 is about four times the intensity of the microwave reaching the second microwave detection sensor 16. Therefore, it is possible to realize two microwave detection means that require different sensitivities by using one type of microwave detection sensor.

[0017]

As described above, the following effects can be obtained in the high frequency heating apparatus of the present invention.

(1) By providing two microwave detection means having different sensitivities using the microwave detection sensor, the reflection amount of the microwave energy which greatly differs depending on the weight of food in a wide range is suitable for its intensity. It is possible to detect the weight of a wide range of foods, and it is possible to automatically cook foods having a wide range of weights.

(2) By attaching two microwave detection sensors having the same sensitivity to the wall surface of the heating chamber at different distances, two microwave detection means which require different sensitivities can be easily obtained by one type of microwave detection sensor. Since it can be realized, an inexpensive high-frequency heating device can be provided due to the effect of mass production on the part unit cost and the reduction of management cost in the manufacturing process.

[Brief description of drawings]

FIG. 1 is a system configuration diagram of a high-frequency heating device according to an embodiment of the present invention.

[Fig. 2] Characteristic diagram of output voltage corresponding value and food weight

FIG. 3 is a sectional view of a main part of a high-frequency heating device according to an embodiment of the present invention.

FIG. 4 is a system configuration diagram of a conventional high-frequency heating device.

[Explanation of symbols]

 1 Heating Chamber 2 Magnetron (Microwave Generation Means) 5 Microcomputer 7 Foods 8, 12, 15, 16 Microwave Detection Means

Claims (2)

[Claims] 1. A heating chamber for heating food, a microwave generating unit coupled to the heating chamber, a microwave detecting unit for detecting a reflection amount of microwave energy from the heating chamber, and the microwave detecting unit. A microcomputer for calculating the output voltage from the means, and an electric storage unit for storing the output voltage corresponding value after the output voltage from the microwave detecting means is calculated by the microcomputer, A high-frequency heating device having two microwave detecting means having different sensitivities and selectively using the two microwave detecting means depending on whether the output voltage corresponding value is higher or lower than a predetermined threshold value. 2. A heating chamber for heating food, a microwave generating unit coupled to the heating chamber, two microwave detecting units for detecting a reflection amount of microwave energy from the heating chamber, and the microwave. A microcomputer for calculating the output voltage from the wave detecting means, and an electric storage section for storing the output voltage corresponding value after the output voltage from the microwave detecting means is calculated by the microcomputer. A high-frequency heating device configured such that the two microwave detecting means having the same sensitivity are attached to the heating chamber wall surface at different distances from the heating chamber outer wall surface.