JPS5813212Y2 - microwave oven - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a microwave oven that can date an object to be heated.

Conventionally, in a microwave oven, a turntable 3 is disposed in a high-frequency heating chamber 2 in an exterior 1, the object to be heated is rotated by the turntable, and at the same time, high-frequency radio waves are irradiated onto the object to be heated from a magnetron 4 to generate uniform high-frequency waves. The structure is such that heating is performed.

Furthermore, when browning the object to be heated 5, the heater 6a
A blower 6b blows air into a hot air forming path 6 comprising a hot air forming path 6, and the hot air generated in the hot air forming path 6 is introduced into the heating chamber 2 and blown onto the object to be heated.

In such a microwave oven, when browning an object, it simply blows hot air from one direction, so only one side of the object can be browned; This was inconvenient as the object to be heated had to be turned over.

In view of these points, this invention heats the object to be heated from below with a heater to brown it, and also provides a wire-mesh-like table so that the object to be heated can be easily browned.
It is made in a strange way so that it can be conveniently dated.

Furthermore, since it is shaped like a wire mesh, this wire mesh-like table is lighter than the high-frequency heating turntable 3, and by taking advantage of the large weight difference between them, this weight is detected when each table is attached, and the circuit is automatically turned on to the high-frequency heating turntable. The heating source side or browning can be switched to the normal heating source side.

An example will be described below.

7 is an exterior, 8 is a high-frequency heating chamber, 9 is a magnetron for supplying high-frequency radio waves, 10 is a waveguide for guiding high-frequency radio waves to the heating chamber 8, and 11 is for placing an object to be heated and rotating it. This is a turntable for.

The turntable 11 is made of heat-resistant glass and has a thick wall for strength, and is therefore quite heavy.

12 is a heated air forming box installed to take in air from the heating chamber 8, heat the air, and discharge it again into the heating chamber 8 and blow it onto the heated object to brown it; 13 is a heater; 14 is a heated air forming box. Inlet of box 12, 15 is heated air forming box 12
A hot air outlet 16 is disposed directly below the heater 13 and forms one side wall of the heated air forming box 12.
3, an infrared transmitting plate for transmitting the infrared rays emitted from 3 and irradiating the object to be heated; 17, a sirocco-type blower fan disposed near the intake port 14 in the heated air forming box 12; 18, an infrared transmission plate; This is a pulley for transmitting power transmitted from a motor (not shown) to the blower fan 17 via a belt (not shown).

The rotation speed of the blower fan 17 can be changed by controlling its drive motor.

19 is a ring-shaped sheathed heater arranged below the turntable 11.

20 is a roller that supports the turntable 11 at its periphery, and 21 is a table support that supports the center of the turntable 11.

The table support 21 and the turntable 11 have a locking protrusion formed on one side and an engaging recess formed on the other side, and when these engaging protrusions and engaging recesses engage with each other, power is generated. It is something that can be conveyed.

22 is a motor for rotating the table support 21 via a motor shaft 23.

A spring 24 is inserted between the exterior board 25 and the motor 22 and elastically pushes the motor 22 upward.

The motor 22 receives stress when rotating the turntable 11 and tries to rotate in the opposite direction to the turntable 11, but a retaining means (not shown) is engaged with the exterior side wall of the motor 22 to prevent this rotation. Therefore, the motor 22 will not be rotated undesirably.

26 is a switch for detecting whether or not the high-frequency heating turntable 11 is placed on the table holder 21. When a heavy turntable 11 is placed on the table holder 21, the motor shaft 23 and the motor 22 are turned off. This motor 22 is pushed down against the spring 24.
The switch 26 is operated when the protruding biasing portion 26a of the switch 26 comes into contact with the protruding biasing portion 26a, and the protruding biasing portion 26a is pushed in.

Note that when the turntable 11 is removed, the table support 21 protrudes upward from the support roller 20, and when the turntable 11 is mounted, the table support 21 and the turntable 11 first contact each other, and then the table bearing 21 is pressed down and the switch 26 is switched, the turntable 11 is brought into contact with the support roller 20.

Although the electric circuit is not particularly shown, the changeover switch 26 has a double-headed contact, and is provided so that the energization path to the magnetron 9 or the energization path to the heater 13 or 19 can be selected by switching the switch. be.

When the high-frequency heating turntable 11 is attached and the changeover switch 26 is energized, the double-headed contact is arranged to fall toward the magnetron side.

On the other hand, when the high-frequency heating turntable 11 is removed, the motor 22 is pushed up by the spring 24, the switch 26 is deenergized, and the double-headed contact falls toward the heater side.

When heating is performed by operating the heaters 13 and 19, the browning shown in FIG. 3 is performed by placing a special lightweight turntable 27 in the shape of a wire mesh on the table holder 21.

The wire-mesh-like turntable 27 includes a disk-shaped drive connection part 27a that removably engages with the table holder 21, and a ring-shaped rail part 27b that rides on the support roller 20.
A rod-shaped member 27C is embedded in the drive connection portion 27a and the rail portion 27b to fix the drive connection portion 27a and the rail portion 27b to each other, and three legs are inserted into three holes formed on the rail portion 27b. The wire mesh portion 27 is formed by locking the
It is formed from d.

Although the electrical circuits are not particularly shown, the heater 13 and the sheathed heater 19 are both set to have the same power consumption at IKW, and are electrically connected so that they cannot operate at the same time in order to keep the rated power of the microwave oven low. There is.

Furthermore, the heat sources 13, 19 are selectively wired so that one can be used alone or both can be activated repeatedly.

When heating both of them repeatedly, these heat sources 13.
19, the operating time ratio of one to the other can be adjusted.

Next, the operation and effect of this embodiment will be explained.

When only high-frequency heating is performed, the turntable 11 made of heat-resistant glass is placed on the table support 21, and the high-frequency generation source 9 is energized.

Then, the object to be heated is heated almost uniformly both inside and outside.

Furthermore, when heating foods such as bread whose flavor is significantly affected by the degree of browning, the glass turntable 11 is removed and a net-like turntable 27 exclusively used for heating burnt dates is used instead. 21
Attach it on top.

Since the mesh turntable 27 is light, the motor 22 is pushed up by the spring 24, so that the switch 26 is deenergized and switched to the side of the energizing path to the heater 13, 19.

Next, as shown in FIG. 4, a heater 1 for forming hot air is installed.
3 is operated for a relatively short time (hour A), then the sheathed heater 19 is operated for a relatively long time (8 hours), and these operations are repeated.

The blower fan 17 is arranged to operate when either heater 13.19 is activated.

Then, the object to be heated such as bread is browned on both the upper and lower surfaces.

At this time, the following characteristics were confirmed through experiments.

Browning with hot air has an extremely high browning ability and can brown the surface of the heated object in a short time, but the browned layer is thin.

Although the browning ability of the sheathed heater 19 is not very high, over time a thick browned white layer with a thin color is formed on the surface of the heated object and from the surface to some extent inside. It is characterized by being formed gradually.

Therefore, the surface of the object to be heated such as bread is browned in a relatively short time by the hot air, and the sheathed heater 1
9, a thick dark white layer is formed from the surface to the inside over time.

In this case, in particular, since the mesh turntable 27 exclusively used for heating the burnt date was used, the hot air heated by the lower sheathed heater 19 was convective and directly hit the surface of the object to be heated and rose along the surface of the object to be heated. Therefore, the heating effect by the sheathed heater 19 increases.

In this way, the area from the surface to the inside of the object to be heated is heated rather slowly by the sheathed heater 19, so that a so-called oven effect is obtained in which the object to be heated is heated while causing a substance change. Things had a very flavorful browning to them.

This device is constructed as described above. ■ Since both sides of the heated object are browned, there is no need to turn the heated object over. ■ Since the convection air from below the heated object directly hits the heated object. The heating effect is increased; (1) When the table is replaced, the switch is automatically switched to the high-frequency heating source side or the heating source for burnt dates, eliminating the need for a dedicated switching knob.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing a conventional example, Fig. 2 is a schematic configuration diagram of an embodiment of this invention, Fig. 3 is a perspective view of a wire mesh turntable, and Fig. 4 shows hot air temperature and sheathed heater temperature. FIG. 11... Weight turntable, 12, 13.1
7... Heating source that heats from above, 19...
...Heating source that heats from below by convection, 21...
...Table support, 26...Switch, 27
・・・・・・A wire mesh table.

Claims (1)

[Scope of utility model registration request] A heating source that heats the object from above, a heating source that heats the object from below by convection, a heavy turntable used for high-frequency heating, and a metal plate used to heat the object from below by convection. A net-like lightweight table is provided, and the table is detachably attached to a table holder, and a switch is provided that detects the weight of the table when the table is attached to the table holder and is switched in accordance with the weight. A microwave oven characterized in that the circuit is selectively switched to the high frequency heating source side or the browning heating source side by switching the switch.