JP2001208356A - Microwave oven - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an microwave oven, which can efficiently cool a high-frequency transmitter and a high-voltage transformer by screening the radiant heat conducted from a high-voltage transformer to a magnetron (high-frequency transmitter) and moreover effectively making use of the cooling air from a fan. SOLUTION: This microwave oven is provided with a magnetron 5, a high- voltage transformer 6, a fan for cooling these, and an intake duct 10 for leading the cooling air from the fan to the magnetron 5. A partition plate 12, which is provided by extending the tip of the intake duct 10 is interposed, abutted against the outer face of the sidewall 1a of a heating chamber 1, between the magnetron 5 and the high-voltage transformer 6. The greater part of the above cooling air is introduced into the intake duct 10 to cool the magnetron 5, whereas its one part passes between the transformer 6 and the partition plate 12, and also blows against the high-voltage transformer 6. At this time, the partition plate 12 screens the radiating heat of the high-voltage transformer 6 conducted to the magnetron 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microwave oven having a high-frequency oscillator and a cooling device for cooling a high-voltage transformer, which heat up during operation of the microwave oven.

[0002]

2. Description of the Related Art Generally, during operation of a microwave oven, electric components such as a magnetron (high-frequency oscillator) and a high-voltage transformer connected to the magnetron become high in temperature due to heat generated by the magnetron. There must be. Conventionally, in order to cool them, a device for cooling by air using a blower fan, a propeller fan, an air duct or the like is built in.

[0005] A cooling configuration in a conventional microwave oven will be described with reference to FIG. In this microwave oven, a heating chamber for accommodating an object to be heated and an electrical equipment chamber 30 are formed adjacent to each other in an exterior. Inside the electric equipment room 30, a waveguide 32 connected to the upper part on the right side of the heating room, and a magnetron 33 for supplying a high frequency to the heating room through the waveguide 32 are provided. Electrical components such as a high voltage transformer 34 and a high voltage capacitor 35 are arranged on the lower plate 30a. A fan 37 that supplies cooling air to the magnetron 33 and the high-voltage transformer 34 and the like is provided behind the electrical equipment room 30 with an appropriate mounting position and angle so that they can be cooled simultaneously.

In order to effectively cool the anode of the magnetron 33, which becomes particularly hot during the operation of the microwave oven,
The magnetron 33 is connected to an intake duct 38 having an opening toward the fan 37 and an exhaust duct 39 for discharging cooling air after cooling the magnetron 33 into a heating chamber.

The cooling air generated by the fan 37 is
Most was guided to the magnetron 33 by the intake duct 38, and a part was blown to the high-pressure transformer 34. (The arrows in the figure indicate the flow of cooling air.)

[0006]

However, in the above-described cooling configuration, the amount of cooling air sent to the high-pressure transformer 34 is small, and the temperature of the high-pressure transformer 34 cannot be sufficiently reduced. For this reason, the radiant heat generated from the high-voltage transformer 34 is transmitted to the magnetron 33, which is one of the factors that makes it difficult to lower the temperature of the magnetron 33.
(Dotted arrows in the figure indicate radiant heat.) In recent years, there has been an increasing need for high-speed heating with a high output even in a microwave oven with a power supply of 100 V, and manufacturers are competing with each other to develop a microwave oven with higher power. When the microwave oven has a high output, the temperature of the anode portion of the magnetron tends to be higher, and it is necessary to increase the cooling efficiency more than before.

Therefore, an object of the present invention is to shield the radiant heat transmitted from the high-voltage transformer to the magnetron (high-frequency oscillator) and to efficiently use the cooling air from the fan to efficiently cool the high-frequency oscillator and the high-voltage transformer. It is to provide a microwave oven.

[0008]

According to a first aspect of the present invention, there is provided a microwave oven, wherein a partition plate is provided between the high-frequency oscillator and the high-voltage transformer, the end portion of the intake duct being extended.

According to a second aspect of the present invention, in the first aspect, the partition plate is in contact with an outer surface of a side wall of the heating chamber.

[0010] According to a third aspect of the present invention, in the microwave oven according to the first aspect, the partition plate is formed of a low heat conductive member.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the same reference numerals indicate the same or corresponding parts.

Referring to FIGS. 1 and 2, reference numeral 1 denotes a heating chamber for storing an object to be heated, 2 denotes a door for opening and closing a front opening of the heating chamber 1, and 3 denotes an electrical equipment room provided adjacent to the heating chamber 1. It is.

The internal structure of the electrical equipment room 3 will be described.
4 is a funnel-shaped waveguide connected to the upper right side of the heating chamber 1;
Is a magnetron provided on the end face of the waveguide 4 and serving as a high-frequency oscillator, and supplies a high frequency into the heating chamber 1 via the waveguide 4. A high-voltage transformer 6 for supplying a high voltage to the magnetron 5 and a high-voltage capacitor 7
Has been arranged.

A fan 9 driven by a blower motor 8 is attached to the rear plate 3b of the electrical compartment 3 as a device for cooling the magnetron 5, the high-voltage transformer 6, and the like. The mounting position and angle of the fan 9 are devised so as to generate cooling air and cool them simultaneously. In order to efficiently cool the anode portion of the magnetron 5 which becomes particularly hot during the operation of the microwave oven, the intake duct 10 has an opening toward the fan 9 and guides cooling air.
And an exhaust duct 11 for discharging the cooling air after cooling into the heating chamber 1 is provided in connection with the magnetron 5.

Reference numeral 12 denotes a partition plate which is provided so as to extend the distal end portion of the intake duct 10 and is disposed between the magnetron 5 and the high-voltage transformer 6. This partition plate 1
2 is formed of a low heat conductive member such as a synthetic resin, for example.

The flow of the cooling air will be described. The fan 9 rotates together with the drive of the blower motor 8 which rotates in the same direction, and generates cooling air. Most of the cooling air is guided to the inside of the intake duct 10, hits a radiating fin 5 a provided in the magnetron 5, and performs heat exchange. At this time, since the cooling air is sent from the same direction, it is possible to more efficiently apply the cooling air to the radiating fins 5a by increasing the size of the radiating fins 5a and changing the length in a stepwise manner. it can. Further, the cooling air after the heat exchange is discharged from the exhaust duct 11 into the heating chamber 1 so that the cooling air flows smoothly. On the other hand, a part of the cooling air passes between the high-pressure transformer 6 and the partition plate 12 and is blown to the high-pressure transformer 6. At this time, since the partition plate 12 is provided in contact with the outer surface of the side wall 1a of the heating chamber 1, the cooling air passing between the high-voltage transformer 6 and the partition plate 12 does not leak upward (to the magnetron 5 side). . That is, since the air passage between the high-pressure transformer 6 and the partition plate 12 is narrow, the speed of the cooling air passing through the air passage increases, and the surface temperature of the high-pressure transformer 6 tends to decrease.
(The arrows in the figure indicate the flow of cooling air, and the dotted arrows indicate radiant heat.) Reference numerals 13 denote legs provided at the four bottom corners of the microwave oven. Leg 1
Reference numeral 3 denotes a conventional leg provided with a moving means to add a function of easily moving the microwave oven. The structure of the leg 13 will be described with reference to FIGS.

The leg 13 includes a mounting bracket 14 attached to the bottom of the main body and a roller 1 rotatably supported by the mounting bracket 14.
5, a roller cover 16 that covers the upper part of the roller 15, and a locking screw 17 that penetrates an insertion hole provided in the roller cover 16 and locks the roller 15. The rollers 15 are made of a material having a high coefficient of friction, for example, rubber or the like, in order to have a property of being difficult to move against vibration. The insertion hole of the roller cover 16 is formed to be screwed with the screw 17.

A method of using the leg 13 will be described with an example. For example, when installing a microwave oven in a limited space where both sides and the upper surface of the microwave oven are surrounded by a wall, a user may have difficulty in handling the microwave oven, and may have difficulty. In such a case, first, the microwave oven is moved to a target position while rolling the roller 15. After the movement, when the locking screw 17 is tightened into the insertion hole of the roller cover 16 from the front side of the microwave oven, the tip of the screw 17 is locked at a part of the surface of the roller 15, and the rotation of the roller 15 is stopped. That is, the rollers 15 are locked, and the microwave oven is fixed at a target position.

When cleaning a table or the like on which a microwave oven is installed, it is easier to work by moving the microwave oven. In such a case, if the screw 17 is loosened, the roller 15 is unlocked, and the microwave oven can be moved.

As described above, the leg portion 13 can be used when it is difficult to install the microwave oven because there is not enough space in the installation space, or when it is desired to move the microwave oven such as at the time of cleaning. Can be fixed to

[0021]

According to the microwave oven of the present invention, the cooling air from the electric fan is collected in the intake duct to cool the high-frequency oscillator and to cool the high-voltage transformer with a part of the cooling air. Since, between the high-frequency oscillator and the high-voltage transformer, a partition plate provided by extending the tip portion of the intake duct is interposed, the radiant heat generated from the high-voltage transformer surface and transmitted to the high-frequency oscillator is shielded, The temperature of the high-frequency oscillator can be easily lowered.

According to the second aspect of the present invention, since the partition plate is in contact with the outer surface of the side wall of the heating chamber, the cooling air passing between the high-pressure transformer and the partition plate does not leak above the partition plate. . In other words, the cooling air path becomes narrower, and the speed of the cooling air passing through the air path increases,
The temperature of the high-voltage transformer is easily lowered.

According to the third aspect of the present invention, since the partition plate is formed of the low heat conductive member, it is possible to further shield radiant heat transmitted to the high frequency oscillator.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a microwave oven according to an embodiment of the present invention.

FIG. 2 is a top sectional view of the microwave oven according to the embodiment of the present invention.

FIG. 3 is an enlarged view of a leg portion of the microwave oven according to the embodiment of the present invention.

FIG. 4 is an enlarged side view of the leg shown in FIG. 3;

FIG. 5 is a side sectional view of a conventional microwave oven.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heating room 3 Electrical room 5 Magnetron (high frequency oscillator) 6 High voltage transformer 9 Fan 10 Intake duct 12 Partition plate

Claims (3)

[Claims] 1. A heating chamber for storing an object to be heated, a high-frequency oscillator for generating a high frequency to be supplied to the heating chamber, a high-voltage transformer for supplying a high voltage to the high-frequency oscillator, an electric cooling fan, and And an intake duct that guides the cooling air to the high-frequency oscillator, and cools the high-frequency oscillator by collecting the cooling air from the electric fan in the intake duct and cools the high-voltage transformer with a part of the cooling air. A microwave oven, wherein a partition plate is provided between the high-frequency oscillator and the high-voltage transformer, with a leading end portion of the intake duct extended. 2. The microwave oven according to claim 1, wherein the partition plate is in contact with an outer surface of a side wall of the heating chamber. 3. The microwave oven according to claim 1, wherein the partition plate is formed of a low heat conductive member.