JP2561522Y2 - High frequency heating equipment - Google Patents

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 provided with a weight detection sensor for measuring the weight of an object to be heated.

[0002]

2. Description of the Related Art Conventionally, a large number of heating and cooking devices for heating food stored in a heating chamber and automatically cooking the food have been put into practical use. Oven cooking and grilled cooking of grilled fish etc. are now possible and convenient. Further, the weight of the food is automatically measured, the heating time and the heating output are determined based on the weight, and the food is automatically heated to improve the usability. In addition, related to this type of heating cooking apparatus is, for example, Japanese Utility Model Publication No. 1-41045 using a strain gauge as a weight sensor, and Japanese Unexamined Patent Publication No. Sho 5 (1993) using a magnet and a Hall element as a food weight sensor.
Nos. 9-12232 and 58-160742 disclose Japanese Patent Application Laid-Open Nos. 61-1723 and 61-3833 using a leaf spring, a magnet and a pickup coil as a weight sensor.
No. 0 is known.

[0003]

However, as the prior art described above, (1) In the case of using a strain gauge, the level of a signal generated at the time of detecting a weight is small because the resistance change of the strain gauge is very small, and thus the conventional technique is generated. It is necessary to increase the signal amplification rate,
And the signal is susceptible to noise.

(2) Those using a magnet and a Hall element are:
Since it is necessary to use a high-precision component as a leaf spring that vibrates according to the weight to be detected, the cost increases.

(3) Those using a leaf spring, a magnet, and a pickup coil are easily affected by variations during assembly and processing.

There have been problems such as the following.

The present invention solves the above-mentioned conventional problems, is economical without using high-precision electronic components, and has a high-frequency heating device provided with a weight detection sensor which is hardly affected by variations during assembly and processing. To provide.

[0008]

In order to achieve the above-mentioned object, a high-frequency heating apparatus according to the present invention comprises an elastic member for displacing a magnetoelectric conversion element in accordance with the weight of an object to be heated placed on a mounting table. Is provided between a pair of magnets attached at appropriate intervals to a part of the magnet, and heats the heated object in accordance with the weight of the heated object detected based on the displacement of the magnetoelectric element and the pair of magnets. Along with controlling the operation of the plurality of heating and cooking energy generating means, a gallium-arsenic-based crystal is disposed on one side of the magneto-electric conversion element, and ferrite is disposed on the other side, and the magneto-electric conversion element is provided with the above-mentioned energy generating means. It is mounted on a substrate provided with an operation control circuit and the like, and the elastic member is made of a non-magnetic material made of an aluminum alloy or the like, and the pair of magnets are fixed to the elastic member with screws of the non-magnetic material.

[0009]

In the present invention, one side of the magneto-electric transducer is made of a gallium-arsenic-based crystal, so that the influence of the ambient temperature on the voltage generated in the magneto-electric transducer is reduced and the other side is made of ferrite. As a result, the magnetic field around the magnetoelectric conversion element becomes stronger, so that a small voltage generated in the magnetoelectric conversion element in response to the minute movement of the magnet can be detected with high sensitivity, and the operation control circuit of the energy generation means can be used for the magnetoelectric conversion element. By providing it on the substrate provided, the assemblability is improved and the coupling member between the substrate and the magnetoelectric conversion element is eliminated, so that the effect of noise exerted on the electric circuit in the substrate by the coupling member is drastically reduced, and the elastic member is made of aluminum alloy. By using a non-magnetic material such as stainless steel, for example, unlike the stainless steel, magnetism is imparted to the elastic member by work hardening during the production of the elastic member. The effect on the magnetic circuit between the magnetoelectric conversion element and the magnet is reduced because it does not occur.Furthermore, the magnet is fixed to the elastic member with a non-magnetic material screw, so that the magnetoelectric conversion element and the magnet are securely fixed. Therefore, even after repeated weight measurement, a constant dimensional relationship is always maintained between the magnetoelectric conversion element and the magnet.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a schematic side sectional view of a high-frequency heating device main body according to the present invention, FIG. 2 is a plan view of a main part of a weight detection sensor of the high-frequency heating device, and FIG. FIG.

In FIG. 1, reference numeral 1 denotes a heating chamber for accommodating an object to be heated, which is formed in a main body H of a high-frequency heating apparatus and has a mesh metal plate 11 arranged on a ceiling. 2 is this heating chamber 1
A high-frequency oscillator for supplying microwaves to the inside;
An oven heater unit provided on the outer back and comprising a fan and a heating element for blowing hot air into the heating chamber 1, and a grill heater 4 provided above the mesh metal plate 11 and heating the inside of the heating chamber 1. The high-frequency oscillation unit 2, the oven heater unit 3, and the grill heater 4 constitute a plurality of heating and cooking energy generating means. Reference numeral 5 denotes a mounting table provided in the heating chamber 1 for mounting an object to be heated, 6 denotes a driving unit provided at the outer bottom of the heating chamber 1 to rotate the mounting table 5, and 7 denotes a lower part of the driving unit 6. And a weight detection sensor that detects the weight of the object to be heated based on the movement of the rotating shaft 61 that moves up and down in accordance with the weight of the object to be heated on the mounting table 5. Reference numeral 71 denotes a support attached to the outer bottom of the heating chamber 1, and the drive unit 6 and an elastic member 72 located below the drive unit 6 are attached to the support 71. The elastic member 72 is a plate-shaped non-magnetic material having a bifurcated tip made of an aluminum alloy or the like. A rivet 75 such as stainless steel is fixed to a portion that comes into contact when the rotation shaft 61 moves downward. I have. Two cylindrical magnets 73 made of strontium ferrite or a rare earth magnet are fixed to the tip of the bifurcated portion so as to face each other in parallel with non-magnetic screws 76 so as to have opposite polarities. Reference numeral 74 denotes a magnetoelectric conversion element (hereinafter referred to as a Hall element) in which one surface side is made of a gallium-arsenic crystal and the other surface side is made of ferrite.
Is mounted so as to be located at a substantially central portion between the two magnets 73, 73 at an appropriate portion of the Hall element 73. The small voltage generated in the Hall element 74 in response to the minute movement of the two magnets 73 can be detected with high sensitivity. The weight of the object to be heated on the mounting table 5 is detected (measured) based on the result. 77 is a substrate,
A weight detection circuit (not shown) for measuring the weight of the object to be heated based on the voltage detected by the Hall element 74 is attached, and the plurality of energy generating means 2, corresponding to the detected weight of the object to be heated, A control circuit (not shown) for controlling the energization of 3 and 4 is provided, and cooking is performed by this control circuit. 78 is a forcible stop for regulating the maximum displacement of the elastic member 72,
The elastic member 72 is formed on the support body 71 located below the rivet 75, and the elastic member 72 is unnecessarily applied so as not to exceed the maximum stress of the elastic member 72 when an excessive load is applied to the rotating shaft 61 of the mounting table 5. It does not bend. Next, the operation of this embodiment will be described.

As described above, since the ferrite attached to the Hall element 74 is located between the two magnets 73, 73, the N.multidot.
The polarity arrangement is SNS, and the magnetic flux density between the two magnets 73 increases toward the end of the magnet 73.

Therefore, when the object to be heated is not mounted on the mounting table 5, the two magnets 73, 73 attached to the elastic member 72 are used.
The Hall element 74 located between them is located at the center between the two magnets 73 having the lowest magnetic flux density.

Next, when the object to be heated is mounted on the mounting table 5,
Hall element 74 located at the center of both magnets 73, 73
The elasticity of the two magnets 73, 73 is set so that the magnets 73, 73 are located from the central part where the magnetic flux density of the magnetic field between the two magnets 73, 73 is low to the end part where the magnetic flux density of the magnetic field between the two magnets 73, 73 is high. The member 72 bends downward without vibrating, and
Move mm. Therefore, when detecting the weight of the object to be heated, the Hall element 74 is positioned in a magnetic field having a magnetic flux density proportional to the weight, and detects a minute voltage generated in the Hall element 74 in response to fine movement of the magnets 73 with high sensitivity. In addition, the output voltage at this time changes linearly according to the minute movement of both magnets 73.

Further, since there is no coupling member (lead wire) between the substrate 77 and the Hall element 74, the influence of noise exerted on the control circuit of the substrate 77 by the coupling member is drastically reduced, and the weight of the object to be heated is further reduced by the Hall element 74. It can be detected accurately.

Further, since the elastic member 72 does not take on magnetism due to work hardening, the influence on the magnetic circuit between the Hall element 74 and the magnets 73 when the weight of the object to be heated is detected is reduced. The weight can be detected more accurately.

Further, the two magnets 73 are connected to a non-magnetic screw 7.
6, the Hall element 74 and the two magnets 73, 73 are securely fixed because the Hall element 74 and the two magnets 73, 73 are secured even if the detection of the weight of the object to be heated is repeated many times.
Since the distance between the positions 73 is always maintained in a constant dimensional relationship, the weight detection accuracy is not affected by the number of times of weight detection.

[0019]

The present invention is configured as described above, so that the following effects can be obtained.

(1) A strong magnetic field is generated around the magnetoelectric conversion element when the weight of the object to be heated is detected, and the minute magnetic field generated in the magnetoelectric conversion element in response to the minute movement of the magnet due to the displacement of the elastic member and changes linearly. Since the voltage can be detected with high sensitivity,
The accuracy of detecting the weight of the object to be heated is improved.

(2) Since the magnetoelectric conversion element is provided on the substrate, not only high-precision parts are not required but also the assemblability is improved.
In addition, there is no coupling member between the substrate and the magnetoelectric conversion element, and the effect of noise exerted by the coupling member on the control circuit in the substrate is drastically reduced. Further, since the elastic member does not become magnetic due to work hardening, the weight of the heated object is detected. In this case, the influence on the magnetic circuit between the magnetoelectric conversion element and the magnet at the time is reduced, the accuracy of detecting the weight of the object to be heated detected by the magnetoelectric conversion element is improved, and the assembly cost can be reduced.

(3) Further, since the magnet is fixed to the elastic member with a non-magnetic screw, the magnet is securely fixed and the magnetoelectric conversion element and the magnet are always maintained in a fixed dimensional relationship even after repeated weight measurement. Therefore, since the weight of the object to be heated detected by the magnetoelectric conversion element is not affected by the number of times of detection, it is less likely to be affected by a variation in installation work of a magnet or the like and an installation error, and accurate weight detection can be performed.

Thus, the operation of the plurality of energy generating means can be controlled accurately, and the object to be heated can be favorably cooked.

[Brief description of the drawings]

FIG. 1 is a schematic side sectional view of an embodiment of the present invention.

FIG. 2 is a plan view of a main part of the weight detection sensor.

FIG. 3 is a side view of a relevant part of a weight detection portion of the weight detection sensor.

[Explanation of symbols]

 2, 3, 4 Energy generating means 5 Mounting table 72 Elastic member 73 Magnet 74 Magnetoelectric conversion element 76 Screw 77 Substrate

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Katsuhiro Yamazaki, Investigator Yoshifumi Muramoto, Examiner, Hitachi Home Tech Co., Ltd. 3-1, Shinjuyoji 2 Kashiwa-shi, Chiba

Claims (4)

(57) [Scope of request for utility model registration] 1. A mounting table (5) on which an object to be heated is mounted, an elastic member (72) displaced in accordance with the weight of the object to be heated mounted on the mounting table (5), and an elastic member (72) a pair of magnets (73) and (73) fixed at appropriate intervals to the magnet (73),
(73) a magnetoelectric conversion element (74) provided between the
(74) and a plurality of heating energy generating means (2), (3) for heating the object to be heated corresponding to the weight of the object to be heated detected based on the displacement of the pair of magnets (73), (73). )as well as
(4) A high-frequency heating apparatus for controlling the operation of (4), wherein a gallium-arsenic-based crystal is disposed on one side of the magnetoelectric conversion element (74) and ferrite is disposed on the other side. . 2. The method according to claim 1, wherein said magnetoelectric conversion element is provided on a substrate provided with a control circuit for controlling the operation of said heating energy generating means. Item 7. The high-frequency heating device according to Item 1. 3. The high-frequency heating device according to claim 1, wherein said elastic member is made of a non-magnetic material made of an aluminum alloy or the like. 4. The high frequency heating apparatus according to claim 1, wherein said pair of magnets (73) are fixed to said elastic member (72) by non-magnetic screws (76).