KR20000013141A - Microwave oven control method to prevent misoperation - Google Patents

Abstract

PURPOSE: A microwave oven control method to prevent a misoperation of the microwave oven is provided to detect a function key which is kept on for longer than prescribed time and turn off the relay to prevent a misoperation of the oven. CONSTITUTION: The microwave oven misoperation preventing control method comprises steps; a load driving step, to detect the inputted key and judge if the operation key is on and turn the relay on to drive the load accordingly; a time counting and judging step, to count the on time of the operation key and judge if the on time of the operation key is longer than prescribed time; a load stop and error display step, to turn off the relay, stopping the load if the on time is judged longer than the prescribed time and to display an error sign to prevent an overload and overheat of the microwave oven.

Description

Microwave malfunction prevention control method

The present invention relates to a microwave control method, and more particularly, to a microwave malfunction prevention control method which prevents a microwave oven from malfunctioning by detecting that the operation key is continuously turned on for a predetermined time or more and turning off the relay. .

In general, a microwave oven is a device for heating / cooking food using microwaves, and a conventional high voltage transformer and a magnetron are provided. This high voltage transformer generates a predetermined high voltage to drive the magnetron, which emits microwaves of high frequency (approximately 2450 MHz) in a confined space where food is stored. The microwave thus vibrates the water molecules contained in the food, and the food is heated / cooked by molecular frictional heat generated by the vibration of the water molecules.

1 is a partially cutaway perspective view illustrating a conventional microwave oven, and FIG. 2 is a circuit diagram of FIG. 1.

According to Figure 1, the cabinet 20 forming the appearance of the microwave oven is divided into a left and right space, one side is provided with a cooking chamber 22, the front is open, the other side lamp (2), fan motor (3), magnetron ( The apparatus room 23 in which various electric appliances, such as MGT), a high voltage transformer (HVT), and a high voltage capacitor (HVC), is installed is provided. An operation panel 25 is provided on the front surface of the apparatus room 23 for operating the microwave oven and displaying the state thereof.

In addition, the door 21 that opens and closes the front of the cooking chamber 22 is rotatably fixed to one side of the cabinet 20, and the rotating dish 24 in which food to be cooked is placed in the bottom surface of the cooking chamber 22. Is installed. The rotary plate 24 is rotated by a drive motor and gears not shown on the bottom surface of the cabinet 20 during food cooking to increase cooking efficiency.

2, one end of the first and second commercial alternating lines L1 and L2 is connected to the noise filter 1 on the input side to input a normal commercial AC power supply (110V or 220V), and the other end thereof. HVT is connected to both ends of the primary coil. The noise filter 1 includes the first and second fuses FUSE1 and FUSE2, the capacitors C1 to C3, the inductor L, the resistor R1, and the like. Since it is the same, the detailed description is abbreviate | omitted here.

In addition, first and second temperature switches TCO1 and TCO2, a door switch SW1, and a monitor switch SW2 are connected to the first commercial AC line L1, and the second commercial AC line L2. ) Is connected to the power relay RY3. The first and second temperature switches TCO1 and TCO2 block overheating generated in the microwave cabinet 20 and the magnetron MTG, respectively, and the door switch SW1 and the monitor switch SW2 are doors. In accordance with the open and closed state of the (not shown) to perform a safety function of the microwave oven.

In addition, an inrush relay RY2 and a current limiting resistor R2 are connected in parallel to the power relay RY3. The power relay RY3 applies a commercial AC power supply to the primary coil of the high voltage transformer HVT, and the inrush relay RY2 is a few seconds before the power relay RY3 is turned on. Operation to eliminate inrush current.

A lamp 2, a fan motor 3, and a driving motor 4 are connected between the first commercial AC line L1 and the second commercial AC line L2. In addition, a main relay RY1 for turning on / off the operation of the lamp 2, the fan motor 3, and the driving motor 4 is connected to one end thereof. Here, the other end of the main relay RY1 is connected to the second commercial AC line L2 through the inrush relay RY2 and the power relay RY3.

On the other hand, a key input unit 5 for inputting a user's command and a display unit 6 for displaying various operating states of the microwave oven are provided. In addition, the microcomputer 7 for controlling the on / off operation of the main relay RY1, the inrush relay RY2 and the power relay RY3 in accordance with the input of the key input unit 5 is provided. Here, the microcomputer 7, the key input unit 5 and the display unit 6 are preferably arranged in the operation panel 25 shown in FIG. 1.

In addition, a magnetron (MGT) for generating microwaves and a high voltage capacitor (HVC) and a high voltage diode (HVD) for supplying a double voltage to the magnetron (MGT) are respectively provided on the secondary coil side of the high voltage transformer (HVT). Prepared. In addition, a high voltage fuse (H.V.FUSE) is provided on one side of the high voltage capacitor (HVC), and protects the device by blocking the overcurrent of the high voltage side.

3 is a flow chart illustrating a conventional microwave control method, referring to the operation of the conventional microwave oven configured as described above with reference to the following.

First, the user opens the door 21 and places the food to be cooked in the state in which the cooking chamber 22 is opened on the upper side of the rotating dish 24 inside the cooking chamber 22 through the front of the cabinet 20. Close 21. In this state, the user sets a cooking time and a cooking temperature through the key input unit 5 of the operation panel 25, and inputs an operation key (not shown) for starting cooking (S101).

Thereafter, the microcomputer 7 detects the key input and determines whether an operation key (not shown) is input (S102). Therefore, when the operation key (not shown) is input, the microcomputer 7 operates the microwave by turning on the main relay RY1 and the power relay RY3 to drive the load (S103 to S104).

When the microwave oven is operated as described above, the commercial AC power inputted through the first and second commercial AC lines L1 and L2 is respectively a door switch SW1, a monitor switch SW2, and a high voltage transformer HVT. The high voltage transformer HVT is driven by flowing through the primary coil and loads such as the power relay RY3. At this time, the microcomputer 7 removes the inrush current through the inrush resistor R2 by operating the inrush relay RY2 for a few seconds immediately before the power relay RY3 is turned on.

In addition, a commercial AC power is also supplied to the lamp 2, the fan motor 3, and the drive motor 4 by the main relay RY1, and the lamp 2 illuminates the inside of the cooking chamber 22. The fan motor 3 cools various circuit components in the apparatus chamber 23, and the drive motor 4 rotates the rotary plate 24 inside the cooking chamber 22 so that microwaves are incident evenly on the food of the upper end. do.

In addition, the high voltage transformer (HVT) supplies a high voltage to the high voltage capacitor (HVC), the high voltage diode (HVD) and the magnetron (MGT) through the secondary coil, the magnetron (MGT) generates a microwave to the cooking chamber 22 By releasing to the inside, food put into it is heated / cooked to a desired temperature.

Meanwhile, in the state where the microwave oven is operated as described above, the microcomputer 7 detects a key input to determine whether the operation key (not shown) is off (S105). Accordingly, when the operation key (not shown) is not turned off, the operation state of the microwave oven is maintained. When the operation key (not shown) is turned off, the main relay RY1 and the power relay RY3 are turned off. All loads of the microwave oven are stopped (S106 to S107).

However, in the conventional microwave control method, when the operation key is continuously turned on due to a device or a circuit defect against the user's intention, the power relay, the main relay, and the like continue to be turned on accordingly. Therefore, the microwave oven is continuously driven unless the operation key is forcibly turned off or the power cord is disconnected. Thus, overload and overheating may occur.

Accordingly, an object of the present invention is to solve the problems of the prior art as described above, by detecting that the operation key is continuously on for a predetermined time or more by turning off the relay, the microwave oven is prevented from malfunctioning The present invention provides a control method for preventing malfunction.

1 is a partial cutaway perspective view showing a typical microwave oven,

2 is a circuit diagram of FIG.

3 is a flowchart illustrating a conventional microwave control method;

Figure 4 is a flow chart showing a preferred embodiment of the microwave malfunction prevention control method according to the present invention.

Explanation of symbols on the main parts of the drawings

5: key input unit 6: display unit

7: microcomputer RY1: main relay

RY3: Power Relay

A characteristic of the microwave malfunction prevention control method according to the present invention for achieving the above object is, a load driving step of detecting a key input to determine whether the operation key is on, and accordingly to turn on the relay to drive the load of the microwave And a time count and determination step of counting the on time of the operation key while the load of the microwave is driven, and determining whether the operation key on time is greater than or equal to a predetermined time, and the operation key on time in advance. When it is determined that the predetermined time or more is set, the relay is turned off to stop the load of the microwave oven, and the load stop and error display step of displaying an error accordingly is included.

The method may further include a normal driving step of performing normal driving of the microwave oven when it is determined that the operation key on time is not more than a predetermined time.

Therefore, by detecting that the operation key is continuously turned on for a predetermined time, the relay is turned off to prevent the microwave from malfunctioning, and accordingly, the mandatory operation such as turning the operation key off or disconnecting the power cord is not performed. Without overload and overheating of the microwave oven can be prevented in advance.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the microwave malfunction prevention control method according to the present invention, the same components as in the prior art will be described by applying the same reference numerals.

Figure 4 is a flow chart showing a preferred embodiment of a microwave malfunction prevention control method according to the present invention, whereby the operation of the preferred embodiment according to the present invention in more detail as follows.

The microcomputer 7 detects various key inputs through the key input unit 5 and determines whether an operation key (not shown) is turned on. Accordingly, the microcomputer 7 turns on the relays RY1 and RY3 to drive the load of the microwave oven. The load driving step is performed (S201 to S204).

In more detail, the user opens the door 21 and the food to be cooked in the state in which the cooking chamber 22 is opened through the front of the cabinet 20 on the top of the rotary dish 24 inside the cooking chamber 22. After placing, the door 21 is closed. In this state, the user sets a cooking time and a cooking temperature through the key input unit 5 of the operation panel 25 and inputs an operation key (not shown) for starting cooking (S201). Thereafter, the microcomputer 7 detects the key input and determines whether an operation key (not shown) is input (S202). Therefore, when the operation key (not shown) is input, the microcomputer 7 turns on the main relay RY1 and the power relay RY3 (S203), and operates the microwave oven by the operation of the relays RY1 and RY3. The load is operated (S204).

As described above, since the microwave load is operated and the food is heated / cooked to a desired temperature as described in detail through the prior art, the detailed description thereof will be omitted.

In this state in which the microwave load is driven, the microcomputer 7 counts the on time of the operation key (not shown), and determines whether the operation key on time is greater than or equal to a predetermined time. (S205 to S206).

Therefore, when it is determined that the operation key on time is more than a predetermined time, the relay RY1 and RY3 are turned off to stop the load of the microwave, and the corresponding error is displayed through the display unit 6. The load stop and error display steps are performed (S207 to S209). Therefore, the overload and overheating factors of the microwave oven, which are generated when the operation keys are continuously turned on due to a failure factor of the device and the circuit, are automatically cut off, and the user can immediately recognize the malfunction of the microwave oven by this action.

On the other hand, if it is determined that the operation key on time is not more than a predetermined time, the microcomputer 7 performs a normal driving step of driving a normal microwave oven (S210 to S212).

In this normal driving stage, the microcomputer 7 detects a key input in a state where the microwave oven is normally operated to determine whether the operation key (not shown) is turned off (S210), and the operation key (not shown) is not turned off. In this case, while the operation state (S203 to S204) of the microwave oven is maintained, when the operation key (not shown) is turned off, the main relay RY1 and the power relay RY3 are turned off (S211). The load is stopped (S212).

The present invention is not limited to the above-described specific preferred embodiments, and various modifications can be made by any person having ordinary skill in the art without departing from the gist of the present invention claimed in the claims. Of course, such changes are intended to fall within the scope of the claims set forth.

As described above, according to the method for preventing malfunction of the microwave oven according to the present invention, by detecting that the operation key is continuously turned on for a predetermined time or more, the microwave is prevented from being malfunctioned by turning off the relay. There is an effect that can prevent the overload and overheating of the microwave oven to occur without forcing the key or disconnecting the power cord.

Claims (2)

A load driving step of detecting a key input to determine whether the operation key is on, and driving the load of the microwave by turning on the relay accordingly; A time counting and determining step of counting an on time of the operation key while the load of the microwave is driven and determining whether the operation key on time is equal to or greater than a predetermined time; And determining that the operation key on time is greater than or equal to a predetermined time, by stopping the load of the microwave by stopping the relay, and including a load stop and an error display step of displaying an error accordingly. How to prevent malfunction of the stove. The method of claim 1, further comprising a normal driving step of performing normal driving of the microwave when it is determined that the operation key on time is not more than a predetermined time.