KR20070053571A - Method for preventing overheat of microwaveoven - Google Patents

Abstract

The present invention relates to a microwave overheating prevention method that prevents overheating of a microwave oven by adjusting a low power driving time according to a time difference between a previous cooking end time and a current cooking start time. Checking the time difference with the time and judging whether the time difference has passed the cooling time, and if the time difference does not pass the cooling time, after calculating the low output driving start time of the microwave oven, it is driven from the low output driving start time to the low output. It is done.

Microwave Oven, Cooling Time, Normal Output, Variable Output, Overheat

Description

Method for preventing overheat of microwaveoven

1 is a circuit diagram of a typical microwave oven.

2 is a flow chart of a method for preventing overheating of a microwave oven according to the present invention.

3 is a view showing the hourly output level before the cooling time elapses according to the present invention.

Figure 4 is a view showing the output level by time after the cooling time in accordance with the present invention.

<Explanation of symbols for the main parts of the drawings>

10: key input unit 20: control unit

30: sub relay 40: main relay

50: fan motor 60: tray motor

70: high voltage transformer 80: fuse

90: door switch

The present invention relates to a microwave oven, and more particularly, to a microwave overheating prevention method for preventing overheating of a microwave oven by adjusting a low output driving time according to a time difference between a previous cooking end time and a current cooking start time. will be.

In general, a microwave oven is a cooker applying the principle that the pores in a metal casing generate heat by its own molecular motion using electromagnetic waves of approximately 2450 MHz.

In such a microwave oven, an electric wave of approximately 2450 MHz is oscillated in the magnetron and guided into the cooking chamber, and the molecules constituting the food are charged with + and-by the induced high frequency. At this time, one side of the molecule is charged with-on the + side of the electric field due to radio waves, and the other side of the molecule is charged with + on the-side of the electric field.

However, since the polarity of the electric field changes 2.45 billion times a second due to radio frequency propagation, the food molecules are severely collided with each other, causing frictional heat to heat the food.

1 is a circuit diagram of a general microwave oven, and as shown in the drawing, a fan motor 50 for driving a cooling fan for cooling various electrical components is connected to a power supply terminal for supplying commercial AC power. Tray motor 60 for rotating the train of the cooking chamber is connected in parallel to 50, the power supply terminal is connected to the high voltage transformer 70 for supplying high voltage power to the magnetron.

In addition, the fuse 80 of the power supply terminal and the fan motor 50 and the door switch 90 which is turned on / off according to the opening and closing of the door are connected in series, and the sub relay 30 is connected to the power supply terminal and the fan motor 15. Is connected, and the main relay 40 is connected between the fan motor 50 and the primary coil of the high voltage transformer 70.

In addition, the controller 20 outputs a control signal for controlling on / off of the main relay 40 and the sub relay 30 according to the key signal input from the key input unit 10, and the sub relay 30 controls the controller. Commercial AC power supplied on / off by the control signal of (20) supplied through the power terminal is supplied to or blocked from the fan motor 50, the tray motor 60, and the high pressure transformer 70. In addition, the main relay 40 is turned on or off by the control signal of the control unit 20 to supply or cut off the commercial AC power supplied from the power supply terminal to the high voltage transformer 70.

The microwave oven controlled the output level according to the cooking time because the microwave power was supplied to the high voltage transformer to continuously drive the magnetron for a long time, causing overheating of various electric parts including the high voltage transformer.

However, the method of controlling the output level according to the cooking time does not consider the problem that the inside of the cooking chamber is overheated because it does not consider the cooling time required for cooling the inside of the cooking chamber by releasing heat after the previous cooking.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and a microwave overheating prevention method for preventing overheating of a microwave oven by adjusting a low power driving time according to a time difference between a previous cooking end time and a current cooking start time. The purpose is to provide.

The configuration of the present invention devised to achieve the above object is as follows. The present invention relates to a method of controlling the output to prevent overheating of the microwave oven, when starting the driving according to the cooking conditions, checking the time difference between the previous cooking end time and the current cooking start time, and the time difference and the preset cooling time In comparison, the output of the microwave oven is controlled according to whether or not the time difference has passed the cooling time.

Here, if the time difference does not pass the cooling time, the low output driving start time of the microwave oven is calculated and outputs normally until the low output driving start time elapses, and when the low output driving start time elapses, the low output driving start time is elapsed.

Low output drive start time is

Low output drive start time = A × (time difference) + Normal output basic drive time

It is calculated according to, A is a constant 2, the normal output basic drive time is the minimum time to output a normal time when the time difference does not pass the cooling time, characterized in that the normal output basic drive time is 5 minutes.

In addition, when the low output drive start time has elapsed and the low output drive time has elapsed, it is determined whether the preset variable output setting time has elapsed, and the drive is repeatedly driven to the normal output and the low output whenever the variable output setting time has elapsed. It is characterized by 10 minutes.

On the other hand, when the time difference passes the cooling time, it is characterized in that the drive to the normal output until the predetermined normal output setting period elapses.

The cooling time is 10 minutes, and the low power drive of the microwave oven is driven at 70% of the normal power.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described in detail.

2 is a flowchart of a method for preventing overheating of a microwave oven according to the present invention, FIG. 3 is a view showing an output level for each hour before the cooling time elapses according to the present invention, and FIG. 4 is an output level for each hour after a cooling time elapses according to the present invention. It is a diagram showing.

The method for preventing overheating of the microwave oven according to the present invention is to prevent overheating of the microwave oven by adjusting a low power driving time according to a time difference between a previous cooking end time and a current cooking start time, as shown in FIG. 2. When the driving according to the condition is started (S10), the time difference between the previous cooking end time and the current cooking start time is checked (S20).

As such, when the time difference between the previous cooking end time and the current cooking start time is checked, the time difference is compared with the preset cooling time to determine whether the time difference has passed the cooling time (S30).

In this case, when the cooling time has elapsed, the drive is driven to the normal output (S70), the time is counted from the time at which the normal output is started, and it is determined whether the counted time has passed the preset normal output setting time (S80). If the counted time does not pass the normal output setting time, the drive continues to the normal output. If the counted time passes the normal output setting time, the drive continues to the low output (S90) and then drives to the variable output. This will be described later.

In addition, the normal output setting time is determined according to the cooling time, which is 27 minutes when the cooling time is set to 10 minutes.

On the other hand, if the time difference between the previous cooking end time and the current cooking start time does not pass the cooling time, the low output drive start time is calculated (S50).

The low output driving start time is calculated by the following equation.

Low output drive start time = A × (time difference) + Normal output basic drive time

Where A is a constant and the normal output basic drive time is 5 minutes.

For reference, the normal output basic driving time means the minimum time for normal output when the time difference does not pass the cooling time.

According to Equation 1, when the low output start time for each time difference is calculated,

If the time difference is less than 1 minute, the low power drive start time is 7 minutes after the current cooking start time. If the time difference is less than 2 minutes, the low power drive start time is 9 minutes from the current cooking start time, and if the time difference is less than 9 minutes The low power drive start time is 23 minutes after the current cooking start time, and when the time difference is less than 10 minutes, the low power drive start time is 25 minutes after the current cooking start time.

On the other hand, when the time difference exceeds 10 minutes, that is, when the cooling time is exceeded, as described above, it is 27 minutes after the normal output setting time from the current cooking start time.

As described above, when the low output driving start time corresponding to each time difference arrives, the drive is driven at a low output and at a variable output.

That is, if it is driven at low output, it is determined whether the variable output set time is preferably 10 minutes (S100). If the variable output set time has not elapsed, the drive continues to low output, and if the variable output set time has elapsed, it is driven at normal output (S110). )do.

When driving to the normal output as described above, it is determined whether the variable output setting time, that is, 10 minutes has elapsed (S120), and if the variable output setting time has not elapsed, the drive continues to the normal output, and when the variable output setting time has elapsed, the low output again. The process of driving (S90) is repeatedly performed. That is, whenever the variable output setting time elapses, the drive is repeatedly driven to low output and normal output. This variable output is continued until cooking is complete.

The present invention is not limited to the above-described embodiments and can be carried out in various modifications within the scope of the technical idea of the present invention.

According to the present invention configured as described above, it is possible to prevent overheating of the microwave oven by adjusting the low-power driving time in accordance with the time difference between the previous cooking end time and the current cooking start time.

Claims (9)

In the method of controlling the output to prevent overheating of the microwave oven, When the driving according to the cooking condition is started, the time difference between the previous cooking end time and the current cooking start time is checked, and the time difference is compared with a preset cooling time to determine whether the time difference has passed the cooling time. A microwave overheating prevention method, characterized in that to control the output of the range. According to claim 1, If the time difference does not pass the cooling time, the low output drive start time of the microwave oven is calculated and outputs normally until the low output drive start time has elapsed, and when the low output drive start time has elapsed Microwave oven overheating prevention method characterized in that driven at a low output. The method of claim 2, wherein the low power drive start time is Low output drive start time = A × (time difference) + Normal output basic drive time Is calculated according to Here, A is a constant 2, and the normal output basic driving time is the minimum time for the normal output when the time difference does not pass the cooling time. 4. The method for preventing overheating of a microwave oven according to claim 3, wherein the normal output basic driving time is 5 minutes. The method of claim 2, wherein when the low output driving start time elapses and the low output driving time has elapsed, it is determined whether a preset variable output setting time has elapsed and repeatedly drives to the normal output and the low output whenever the variable output setting time elapses. Method for preventing overheating of the microwave oven, characterized in that. 6. The method of claim 5, wherein the variable output setting time is 10 minutes. The overheat prevention method of the microwave oven according to claim 1, wherein when the time difference passes the cooling time, driving is performed at a normal output until a preset normal output setting period elapses. The method of claim 1, wherein the cooling time is 10 minutes. 3. The method of claim 2, wherein the low power drive of the microwave oven is driven at 70% of the normal output power.

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