JPH0221694Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a microwave oven that improves the heating efficiency inside the oven when the oven is used.

Generally, microwave ovens with oven function are
Depending on the food and menu, you can switch between three types of heating: (1) microwave heating only, (2) heater heating only, and (3) a combination of microwave heating and heater heating (hereinafter referred to as combination heating). I'm starting to be able to do it.

By the way, in microwave ovens in which a stirrer fan is installed at the end of the waveguide and the stirrer fan is rotated by the air blowing from the blower fan in order to uniformly irradiate the heating chamber with microwaves, cooling air leaks from gaps in the waveguide cover. This caused the heat to enter the heating chamber and prevent the temperature from rising in the heating chamber. Particularly in the case of only heater heating, there is a problem in that the heating chamber is cooled down by the rotation of the stirrer fan.

The present invention has been made in view of the above points, and aims to improve thermal efficiency by controlling air flow from the blower fan to the stirrer fan and the heating chamber in the case of combination heating and heater heating only.

In order to achieve the above-mentioned object, the present invention includes an opening formed in the side wall of the heating chamber to guide air from the blower fan into the heating chamber, and a waveguide to guide the air from the blower fan to the waveguide. Two openings are opened and closed individually in conjunction with a control lever that switches between three types of cooking: (1) microwave heating only, (2) heater heating only, and (3) combination heating. It is characterized by being equipped with a damper mechanism.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 is a perspective view of a microwave oven showing an embodiment of the present invention with the cabinet removed, and FIG. 2 is a schematic front view of FIG. 1.

In the figure, reference numeral 1 denotes a microwave oven body equipped with a door 3 for opening and closing a heating chamber 2, an operation panel 7 equipped with an operation lever 4 for setting the type of cooking, a timer 5, a heating start switch 6, etc. 7
Electrical components such as a high-voltage transformer 9, a blower fan 10, a duct 11, and a magnetron 12 fixed to the bottom plate 8 are arranged on the back side. Reference numeral 13 denotes a waveguide connected to the magnetron 12, and a stirrer fan 14 for uniformly irradiating microwaves into the heating chamber is installed at the terminal end 13' of the waveguide. It's open. Reference numeral 15 denotes a punching hole formed in the side wall surface 2'' of the heating chamber 2, and during microwave heating, water vapor generated from the heated food is exhausted through the punching hole formed in the top plate 2' by air blown by the blower fan 10. 16 to the outside. 17 is a punching hole provided on the waveguide 13 side, which introduces air from the blower fan 10 into the waveguide 13, rotates the stirrer fan 14, and closes the waveguide. end 1 of
It is discharged to the outside from the punched hole 18 at 3'. Reference numeral 19 is an exhaust port provided on the rear plate 20, and the magnetron 1 is
2 is cooled and then discharged to the outside. Reference numeral 21 denotes an air intake port provided in the bottom plate 8, through which air is taken in from the outside by the blower fan 10 and blown to each part as described above.

Next, a damper mechanism for controlling the air introduced into the punching hole 15 formed in the side wall surface 2'' of the heating chamber 2 and the punching 17 provided on the waveguide 13 side will be described.

3 is a schematic top view of the main part of the operating lever 4, FIG. 4 is a perspective view of the oven damper duct 22 attached to the side wall surface 2'' of the heating chamber 2, and FIG. It is a front view a and a side view of the waveguide damper duct 23 formed in series.

In the figure, the operating lever 4 is pivoted on a fulcrum 24 so as to be horizontally rotatable relative to the operating panel 7, and a lever actuating portion 4' extends from the fulcrum 24 in a substantially perpendicular direction. A damper 25 opens and closes the opening 22' of the oven damper duct 22, and is attached to the oven damper shaft 25' so as to be rotatable in the direction of arrow P. 26 is a rod having one end engaged with the upper end of the damper 25 and the other end engaged with the lever operating portion 4' via a spring 27; 28 is a damper for opening and closing the waveguide damper duct 23; It is attached to the waveguide damper shaft 28' so as to be rotatable in the direction of the dovetail arrow Q. Reference numeral 29 is a spring for always biasing the damper 28 to open, and reference numeral 30 is a rod having one end engaged with the substantially central upper end of the damper 28 and the other end engaged with the lever operating portion 4'. be.

Now, to explain the operation of the embodiment of the present invention having the above configuration, first, when the operating lever 4 is set to the [ ] position, the rod 26 is pushed out in the direction of the arrow R, and the damper 25 is moved to the third position. Open as shown in the figure. On the other hand, the damper 28 is opened by a spring 29. in this case,
The air supplied by the blower fan 10 is introduced into the heating chamber 2 and the waveguide 13, and the stirrer fan 14 is rotated by this air, thus providing an example of use suitable for microwave heating. Next, when the operating lever 4 is switched to the [ ] position, the rods 26 and 30 are pulled in the direction of the arrow S, so the damper 25 is closed, but since the urging force of the spring 29 is strong, the damper 28 will continue to be open, and the oven damper 25 will be closed, cutting off air from the punched hole 15 into the heating chamber 2. However, since the waveguide damper 28 will remain open, the stirrer fan 14 will not rotate. Since the heating chamber 2 can be uniformly irradiated with microwaves in this manner, it is suitable for performing combination heating in which microwave heating and heater heating are combined. Next, when the operating lever 4 is switched to the [ ] position, the rods 26 and 30 are further pulled in the direction of the arrow S, so that the damper 28 finally closes against the biasing force of the spring 29. Since also continues to be closed, air from the blower fan 10 is no longer supplied to the heating chamber 2 or the waveguide 13. Therefore, the heating chamber 2 is efficiently heated by the heater, and is suitable for cooking using only heater heating. When the operating lever 4 is set to the heating cooking mode in this manner, the oven damper and the waveguide damper are closed at the same time, so that no unnecessary air is blown into the heating chamber.

As explained above, in the present invention, in a microwave oven with an oven function equipped with a stirrer fan, the oven damper is closed and the waveguide damper is opened during combination heating.
Although the blowing of air from the blower fan into the heating chamber is blocked, the blowing of air to the waveguide is not blocked, so the stirrer fan rotates. Therefore, the thermal efficiency of heater heating is improved and the microwaves are uniformly irradiated, so that combination cooking can be performed efficiently. In addition, since both dampers are closed when heating only with the heater, the stirrer fan stops and unnecessary air does not enter the heating chamber, improving thermal efficiency and making it possible to rapidly raise the temperature of the heating chamber. This has excellent effects.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a microwave oven with the cabinet removed showing an embodiment of the present invention, Fig. 2 is a schematic front view of Fig. 1, and Fig. 3 is a schematic top view of the main part of the operating lever section. , FIG. 4 is a perspective view of the oven damper duct, and FIG. 5 is a front view a and a side view b of the waveguide damper duct. 1... Microwave oven, 2... Heating chamber, 4... Control lever, 10... Blower fan, 13... Waveguide, 14... Stirrer fan, 22... Oven damper duct, 23... Waveguide damper duct , 25, 28... damper, 26, 30... rod.

Claims (1)

[Scope of Claim for Utility Model Registration] An operation panel provided with an operation lever for switching between three types of cooking: microwave heating only, combination heating of microwave heating and heater heating, and heater heating only, and the operation panel. A blower fan and a magnetron are arranged on the back side of the blower fan, a waveguide is connected to the magnetron, and a stirrer fan is installed inside the waveguide and rotated by the air blown from the blower fan. A microwave oven comprising: a first opening formed in a side wall of the heating chamber to guide air from the blower fan into the heating chamber; and a first opening formed in the side wall of the heating chamber to guide air from the blower fan into the waveguide. The formed second opening is linked with the operation lever to open both openings in the case of microwave heating only, and to open only the second opening in the case of combined heating of microwave heating and heater heating. A microwave oven characterized in that it is provided with two dampers that open both openings and close both openings when heating only with the heater.