JPS6153840B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high-frequency heating device having a variable output function for a high-frequency generator and a variable output function for a heater.

Generally, high-frequency heating devices, so-called microwave ovens, include a variable output function for a high-frequency generator such as a magnetron, and a variable output function for an upper heater and a lower heater during oven cooking. By the way, in such a microwave oven, the variable output to the magnetron and the variable output to the heater are performed by independent devices, respectively, and this results in a problem that the structure is complicated and the cost is high.

This invention has been made in view of the above circumstances, and its purpose is to provide a high-frequency heating device that is to be provided with a variable output function for the high-frequency generator and a variable output function for the heater.
To provide a high-frequency heating device that can be simplified in configuration, thereby making it possible to effectively utilize space and reduce costs, and also capable of varying outputs to a plurality of heaters with extremely simple operations.

An embodiment of the present invention will be described below with reference to the drawings. In Figures 1 and 2, 1
1 is a main body of a microwave oven, and a door 2 is pivotally supported on the front surface so as to be openable and closable, and an operation panel 3 is provided. A cooking chamber 4 is disposed within the main body 1 corresponding to the door 2. One end of a waveguide 5 is communicated with the ceiling surface of the cooking chamber 4, and a high frequency generator such as a magnetron 6 is provided around the other end of the waveguide 5. Here, the antenna ₆₁ of the magnetron 6 is introduced into the waveguide 5, so that the high frequency waves emitted from the magnetron 6 are supplied into the cooking chamber 4. Furthermore, a rotary shelf board 7 for placing food to be cooked is provided in the lower part of the cooking chamber 4.
is connected to the rotating shaft. Further, in the cooking chamber 4, a predetermined heater, for example, an upper heater 9, is disposed in an upper part, and a heater other than the predetermined heater, for example, a lower heater 10, is disposed in a lower part, that is, on the back side of the shelf board 7.

On the other hand, the operation panel 3 includes a microwave cooking setting switch 11, an oven cooking setting switch 12,
High frequency output scale 13, output setting knob 14, heater output scale 15, timer knob 16, cooking lamp 17, cooking switch 18, and power switch 19
are arranged sequentially from the upper part to the lower part. Here, FIG. 3a shows the height of the high-frequency output determined according to the scale position of the scale 13. That is, as the pointer 13a is set to the right in the figure, the output of the magnetron 6 becomes higher. Also, Figure 3b
indicates the level of each heater output determined according to the scale position of the scale 15. That is, as the pointer 15a is set to the right in the drawing, the output of the upper heater 9 becomes higher, and conversely, the output of the lower heater 10 becomes lower.

FIG. 4 shows the control circuit. The AC power supply 30 includes
A timer motor 33 is connected through the power switch 19, door switch 31, cooking switch 18, and timer switch 32 in series. This timer motor 33 includes the motor 8 and the relay 3.
4 and output variable device 40 are connected in parallel. And the normally open contact 34a of the relay 34
are connected in parallel to the cooking switch 18.
Note that the output variable device 40 has a changeover switch 41, which will be described later. The power source 30 also includes the power switch 10, the normally open contact 34b of the relay 34,
34c, one contact of the changeover switch 50 (between the movable terminal 50c and the fixed terminal 50m), and one contact of the changeover switch 41 (between the movable terminal 41c and the fixed terminal 41a) are connected to the transformer 6 in series.
0 primary winding 61 is connected. The anode and cathode of the magnetron 6 are connected to the secondary winding 62 of the transformer 60 via a rectifier circuit consisting of a capacitor C and a diode D.
Its anode is grounded. Furthermore, the heater of the magnetron 6 is connected to the secondary winding 63 of the transformer 60. On the other hand, the power supply 30 includes a power switch 1.
0, normally open contacts 34b and 34c of the relay 34, the other contact of the changeover switch 50 (between the movable terminal 50c and the fixed terminal 50h), the switch 51, and one contact of the changeover switch 41 (between the movable terminal 41c and the fixed terminal) 41a) is connected in series to the upper heater 9. Furthermore, the power supply 30 includes a power switch 10, a normally open contact 34b of the relay 34,
34c, the other contact point of the changeover switch 50 (between the movable terminal 50c and the fixed terminal 50h), and the other contact point of the changeover switch 41 (between the movable terminal 41c and the fixed terminal 41b) are connected in series to the lower heater. 10 are connected.

That is, in the changeover switch 50, when microwave cooking is set by the switch 11, one contact 50c-50m is turned on to form an energizing path for the magnetron 6, and when oven cooking is set, the other contact 50c is turned on. -50h is turned on to form an energizing path to heaters 9 and 10, which will be described later. One contact 41c-41a of the changeover switch 41 is inserted into the current conduction path for the magnetron 6 and the current conduction path for the upper heater 9, and the other contact 41c-41b of the changeover switch 41 is inserted into the current conduction path for the lower heater 10. It is in a state of contact. The changeover switch 41 has a pair of contacts that are turned on alternately in conjunction with the operation of the output variable device 40, and the on time of one contact 41c-41a and the on time of the other contact 41c-41b correspond to the output setting. It is designed to relatively increase or decrease depending on the setting position of the knob 14. Further, the switch 51 is turned off during microwave cooking by interlocking with the changeover switch 50.
It serves to prevent the heaters 9 and 10 from being energized when the other contact 41c-41b of the changeover switch 41 is turned on.

Next, the operation in the above configuration will be explained.

First, we will discuss the case of microwave cooking. Turn on the power switch 18 and turn on the cooking chamber 4.
The food to be cooked is placed on the shelf board 7 inside, and the door 2 is closed. Then, the user turns on the switch 11 to set microwave cooking, sets the cooking time with the timer knob 16, and sets the high frequency output scale 13 to a desired value by operating the output setting knob 14. In this way, when preparation for cooking is completed, the cooking switch 19 is turned on. Then, the timer motor 33, motor 8, relay 34, and output variable device 40 each operate. Then, the magnetron 6 is oscillated intermittently with a predetermined duty by a changeover switch 41 that responds to the output variable device 40, and the food to be cooked in the cooking chamber 4 is heated by the high frequency waves emitted from the magnetron 6. . After that, when the preset cooking time has elapsed, the timer switch 32 is released and the microwave cooking ends.

Next, the case of oven cooking will be described. The food to be cooked is placed on the shelf board 7 in the cooking chamber 4, and the door 2 is closed. Then, the user turns on the switch 12 to set oven cooking, sets the cooking time with the timer knob 16, and sets the heater output scale 15 to a desired value by operating the output setting knob 14. In this case, if the surface of the food to be cooked is to be browned, the pointer 15a of the heater output scale 15 is set to the right position in FIG. 3b, and the upper heater output is set high. In this way, when preparation for cooking is completed, the cooking switch 19 is turned on. Then, the timer motor 33, motor 8, relay 34, and output variable device 40 each operate. Then, the upper heater 9 and the lower heater 10 are operated alternately for a predetermined period of time by a changeover switch 41 that responds to the output variable device 40.
The food to be cooked is heated by the heat generated. In this case, since the upper heater output is set high at the time of output setting, the operating time of the upper heater 9 is long and, conversely, the operating time of the lower heater 10 is short. After that, when the preset cooking time has elapsed, the timer switch 32 is opened and the oven cooking ends.

Therefore, since the oscillation output of the magnetron 6 and the output of the upper heater 9 and the lower heater 10 are changed by a common output variable device 40, the configuration can be simplified, and space can be made more efficient. This makes it possible to utilize the technology and reduce costs.
Further, since the output of the upper and lower heaters can be simultaneously changed to a high output and a low output using this output variable device, the output of each heater can be varied with an extremely simple operation.

Note that the number of heaters disposed in the heating chamber is not limited to the above embodiment, and for example, 2 heaters.
This can be implemented in the same manner even when an upper heater for grill cooking is provided in addition to the main heater. In addition, the present invention is not limited to the above-mentioned embodiments, and it goes without saying that various modifications can be made without changing the gist.

As described above, according to the present invention, by having the configuration as described above, the output variable for the high frequency generator and the output variable for the heater can be performed by a common output variable device, and moreover, this output variable device can be used for multiple output variable devices. Since the output of each of the heaters can be varied at the same time, the configuration of the high-frequency heating device, which should be equipped with a variable output function for the high-frequency generator and a variable output function for the heater, can be simplified, and this makes effective use of space and costs. It is possible to provide a high-frequency heating device that can reduce the amount of heat generated by heating, and when there are multiple heaters, can vary the output of each heater with an extremely simple operation.

[Brief explanation of the drawing]

The drawings show one embodiment of the invention.
The figure is an external view, Figure 2 is a diagram schematically showing the internal mechanism, and Figures 3a and 3b are diagrams showing the heights of the high-frequency output corresponding to the high-frequency output scale and the heights and lows of the heater output corresponding to the heater output scale, respectively. , FIG. 4 is a block diagram of the control circuit. 6...High frequency generator (magnetron), 9...
...Upper heater, 10...Lower heater, 13...High frequency output scale, 14...Output setting knob, 15...Heater output scale, 40...Output variable device.

Claims (1)

[Claims] 1. Selectively forming a heating chamber, a high-frequency generator that supplies high-frequency waves into the heating chamber, a plurality of heaters disposed within the heating chamber, a conduction path for the high-frequency generator, and a conduction path for each heater. The output variable device is equipped with a changeover switch for the output, an output setting knob, and a pair of contacts whose ON time is relatively increased or decreased depending on the setting position of the output setting knob, and one of the output variable devices Inserting a contact into a current-carrying path for the high-frequency generator and a current-carrying path for a predetermined heater of each heater,
A high-frequency heating device characterized in that the other contact of the output variable device is inserted into a current-carrying path for a heater other than the predetermined heater.