JPH1089699A - High frequency heating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate wasteful power consumption while an apparatus is not used. SOLUTION: A control circuit 18 sets a predetermined timer time based upon turning-on of a door switch 16 due to opening of the door and starts subtraction of the timer time based upon trunning-off of a door switch 26 due to closing of the door, during which when a signal of a door switch circuit 26 and a signal of a key input circuit 23 are not inputted, it turns off a relay 17 when the timer time is over and interrupts power supply to the control circuit 18. In contrast, it continuously performs indication of a clock for example without turning off power opening/closing means 19 even after the clock of the predetermined timer time is completed after the door is closed when a predetermined instruction is provided from the key input circuit 23.

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 device such as a microwave oven controlled by a control circuit having a microcomputer (hereinafter referred to as a microcomputer).

[0002]

2. Description of the Related Art Conventionally, a high-frequency heating device controlled by a control circuit having a microcomputer has been supplied with power to the control circuit even when cooking is not performed (for example, Japanese Utility Model Laid-Open No. 55-1164). )

[0003]

A high-frequency heating device operated by a control circuit provided with a microcomputer can detect a key input or operate a clock even when food is not heated.
Power was always supplied to the control circuit.

[0004] The fact that power is always supplied to the control circuit of the device, which has a very short usage time per day, from the actual use situation, is very wasteful even if the consumed power is small.

However, there are times when it is desired to always display a clock or the like, and it is also important to be able to respond to such requests.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a heating source for heating food, a key input circuit for setting the operation contents of the heating source, and a door opening / closing detecting door opening / closing. A control circuit including a detecting means for controlling the operation of the heating source; a power supply circuit serving as a power supply of the control circuit; and a power supply circuit interposed between a commercial power supply and the power supply circuit, which is turned on and closed by opening a door. In a high-frequency heating device including a door switch that is turned off in the configuration, a reset circuit that resets the control circuit when it is detected that power is supplied to the control circuit through the power supply circuit is provided in the control circuit.
N, the power switching means for connecting the commercial power supply to the power supply circuit is connected in parallel to the door switch, and the control circuit comprises:
When the door was opened and the door switch was turned on and power was supplied from the commercial power supply to the power supply circuit, the door was reset by the reset circuit to set a predetermined timer time, and then the door opening / closing detection means detected that the door was closed. When the time of the predetermined timer time is started, and the door opening / closing detecting means does not detect the opening of the door or the key input of the key input circuit is not performed while the time of the predetermined timer time is being measured. While turning off the power switching means, the high frequency heating device is configured so that the power switching means is not turned off after the door is closed when a predetermined instruction is given from the key input circuit and the timer of the predetermined time is finished. Was configured.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is constructed as described above, and a control circuit is provided by a reset circuit when a door switch is turned on by opening a door and power is supplied from a commercial power supply to a power supply circuit. The timer is reset to set a predetermined timer time, and then, when the door opening / closing detection means detects that the door is closed, the timer starts counting the predetermined timer time, and the timer counts the predetermined timer time. In the meantime, when the door opening / closing detecting means does not detect the opening of the door or when there is no key input of the key input circuit, the power opening / closing means is turned off so that power consumption in the control circuit is not performed.

On the other hand, when a predetermined instruction is given from the key input circuit, the power opening / closing means is not turned off after the door is closed and a predetermined timer time has elapsed.
For example, it is possible to continuously display a clock or the like.

[0009]

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

FIG. 1 is a control circuit diagram of a microwave oven. 1 is a commercial AC power supply, 2 is a current fuse, and 3 and 4 are main door switches that are turned on / off in conjunction with opening and closing of doors. Reference numeral 5 denotes a door switch which also serves as a monitor switch. The door switch 5 blows the current fuse 2 when a failure occurs in which the main door switches 3 and 4 do not turn off when the door is opened. 6 is an oven lamp for illuminating the heating chamber during cooking, 7 is a table motor for rotating a turntable at the bottom of the heating chamber, 8 is an electric heater of a heating source, a grill heater provided on the ceiling of the heating chamber, and 9 is the same. Is an oven heater provided at the bottom of the heating chamber, 10 is a high frequency generation source composed of a magnetron or the like, and 11 is a fan motor for cooling the high frequency generation source 10. 12, 1
Reference numerals 3 and 14 are relays which are controlled by a control circuit to be described later and connect the electric heaters 8 and 9 and the high frequency generator 10 to a commercial power supply. Reference numeral 15 denotes a relay, which is provided between the commercial power supply 1 and the power load circuit including the oven lamp 6, the table motor 7, the electric heaters 8, 9, the high frequency generation source 10, and the fan motor 11, and is turned on by a control circuit described later.
/ OFF control. Reference numeral 16 denotes a switch that is turned on when the door is opened and turned off when the door is closed, in conjunction with opening and closing of the door. Reference numeral 17 denotes a relay which is connected in parallel with the door switch 16 and serves as power switching means.
N / OFF control is performed. 18 is a control circuit,
Reference numeral 19 denotes a microcomputer which is an information processing device of the control circuit 18. Reference numeral 20 denotes a power supply circuit of the control circuit 18, which is connected to the commercial power supply 1 and generates a DC voltage by the above-described parallel circuit of the door switch 16 and the relay 17. Reference numeral 21 denotes a reset circuit which, when the power supply circuit 20 is connected to the commercial power supply 1 and a DC voltage rises, detects the DC voltage and outputs a reset signal. Reference numeral 22 denotes an Hz signal circuit that detects the frequency of the commercial power supply 1 connected to the power supply circuit 20 and outputs the detection result. Reference numeral 23 denotes a key input circuit for setting operation contents such as selection of a heating source and setting of a heating time. 24 is a quantity sensor circuit for detecting the weight of food, 25 is a finished sensor circuit for detecting the finished temperature of the food, 2
6 is a door switch circuit for detecting the open / closed state of the door, 27
Is the microcomputer 1 in addition to the type of heating source selected by the key input circuit 23, the heating time, and the weight of the detected food.
Reference numeral 28 denotes a display circuit for displaying the calculation result of 9 and a message for the cook, and 28 denotes an output circuit for driving the relays 12, 13, 14, 15 and 17 based on a command from the microcomputer 19.

Next, the operation of the embodiment of the present invention configured as described above will be described.

The contact states of the switches 3, 4, 5, and 16 in FIG. 1 are those when the door is closed. When the door is closed, the main door switches 3 and 4 are in the ON state, and the switch 5 contacts the contact point b to connect the load to the commercial power supply 1. Since the door switch 16 is OFF, the supply of power to the control circuit 18 through the door switch 16 is shut off.

Next, when the door is opened, switches 3 and 4
At the same time as the FF, the monitor switch 5 comes into contact with the contact a to disconnect the load from the commercial power supply 1 and the door switch 16 is turned on to supply power to the control circuit 18. When the power is supplied, the power supply circuit 20 generates a DC power supply necessary for the operation of the control circuit 18. Further, when the reset circuit 21 detects the rise of the DC power supply of the power supply circuit 20 and outputs a reset signal to the microcomputer 19,
The program of the microcomputer 19 is initialized.

The operation of the microcomputer 19 after the initialization will be described with reference to the general flow of FIG.

This general flow is determined by the ON / OFF state of the relay 17.
Only the control related to the OFF control is shown. When the door is first opened to put food into the heating chamber, the door switch 16 is turned on, and power is supplied to the power supply circuit 20 of the control circuit 18. Then, the reset circuit 21 detects the rise of the power supply of the power supply circuit 20 and outputs a reset signal, so that the program of the microcomputer 19 is initialized. The microcomputer 19 uses the frequency signal input from the Hz signal circuit 22 as a reference signal for time management and the like.

Next, the microcomputer 19 turns on the relay 17 and sets a fixed timer time. Then, after the door is closed, the timer time subtraction is started, and if no key input signal from the key input circuit 23 or a door opening / closing signal from the door switch circuit 26 is input during that time, when the remaining time becomes zero, The relay 17 is turned off.

If a signal is input from the key input circuit 23 or the door switch circuit 26 before the remaining time becomes zero, the timer time is reset and the relay 17
N is extended. The time value of this timer is set to a length long enough for the cook to set a cooking menu from the key input circuit 23 while watching the display circuit 27 or to confirm on the display circuit that cooking is completed. Needless to say.

When the cooker enters the food into the heating chamber, closes the door, sets the heating function through the key input circuit 23, and starts heating, the microcomputer 19 changes from the standby state (timer subtraction state). It becomes a cooking state. After the cooking is completed, the microcomputer 19 resets the timer and starts the subtraction. Note that when the door is opened and closed according to the cooking program, it is not determined that the microwave oven has been unused even if the door is opened and then closed again, so that the cooking program is completed or canceled only. The relay circuit 17 is turned off only when there is no door opening or closing or key input within a predetermined timer time after the control
8 is cut off.

When the door is opened after the relay 17 is turned off, the power supply to the control circuit 18 is resumed.

Further, in the case where the clock display is always required, the relay 1 is always continuously operated by a predetermined key input setting.
7 can be turned on.

[0021]

As described above, according to the present invention, it is possible to provide a high-frequency heating apparatus that does not consume useless electric power by preventing the control circuit from being energized when it is not used as a cooker. On the other hand, it is necessary,
When a predetermined instruction is given from the key input circuit, for example, a clock or the like can be continuously displayed.

[Brief description of the drawings]

FIG. 1 is a control circuit diagram according to an embodiment of the present invention.

FIG. 2 is a general flow diagram of the same.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Commercial power supply 8 Electric heater 9 Electric heater 10 Magnetron 16 Door switch 17 Relay 18 Control circuit 19 Microcomputer 20 Power circuit 21 Reset circuit 23 Key input circuit 26 Door switch circuit

Claims (1)

[Claims] A control circuit for controlling the operation of the heating source, comprising: a heating source for heating the food; a key input circuit for setting the operation content of the heating source; and a door opening / closing detecting means for detecting opening and closing of the door. A high-frequency heating device comprising a power supply circuit serving as a power supply for the control circuit, and a door switch interposed between a commercial power supply and the power supply circuit, which is turned on when the door is opened and turned off when the door is closed. A power switch for connecting the commercial power supply to the power supply circuit when the control circuit is provided with a reset circuit for resetting the control circuit when detecting that power is supplied to the control circuit through the power supply circuit. Means is connected in parallel to the door switch, and the control circuit is configured such that when the door is opened, the door switch is turned on and power is supplied from the commercial power supply to the power supply circuit. Reset by the reset circuit to set a predetermined timer time, and then start counting the predetermined timer time when the door opening / closing detection means detects the closing of the door; and When the door opening / closing detecting means does not detect the opening of the door while the time is being measured, or when the key input circuit does not perform a key input, the power opening / closing means is turned off. The high frequency heating device is characterized in that the power opening / closing means is not turned off even after the time of a predetermined timer time has elapsed after the door is closed when the instruction is given.