KR20070053570A - Method for preventing overheat of microwaveoven - Google Patents

Abstract

The present invention relates to a method for preventing overheating of a microwave oven to prevent overheating of a microwave oven by controlling its output at the start of cooking according to a time difference between a previous cooking end time and a current cooking start time. After checking the current cooking start time and the first step of checking the time difference between the previous cooking end time and the current cooking start time, and determining whether the time difference has passed the preset cooling time, the time difference has passed the cooling time If not, it comprises a second step of driving the microwave oven at low power.

Microwave Oven, Cooling Time, Normal Output, Variable Output

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.

Figure 3 is a view showing the output level by time after the cooling time in accordance with the present invention.

4 is a view showing the hourly output level before the cooling time elapses according to 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, overheating of a microwave oven to prevent overheating of the microwave oven by controlling its output at the start of cooking according to a time difference between a previous cooking end time and a current cooking start time. It relates to a prevention method.

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. The tray motor 60 for rotating the train of the cooking chamber is connected in parallel to the 50, and the power supply terminal is connected to the high voltage transformer 70 for supplying the 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.

The present invention has been made to solve the above-described problems, the present invention is to control the output of the microwave oven according to the time difference between the previous cooking end time and the current cooking start time to prevent overheating of the microwave oven The purpose is to provide a method for preventing overheating.

The configuration of the present invention devised to achieve the above object is as follows. According to the present invention, after checking the previous cooking end time and the current cooking start time, the first step of checking the time difference between the previous cooking end time and the current cooking start time, and determining whether the time difference passes the preset cooling time. If the time difference does not pass the cooling time, characterized in that it comprises a second step of driving the microwave oven at low output.

Here, in the second step, it is determined whether the cooling time has elapsed while the microwave oven is driving at low output, and when the cooling time has elapsed, the microwave is driven at the normal output, and the preset normal output time while the microwave oven is driving at the normal output. When the normal output time elapses by judging whether this has elapsed, it is characterized by repeatedly driving to a low output and a normal output every predetermined time.

In addition, the second step is to increase the output of the microwave every time a certain time elapses until the cooling time has elapsed, while the second step is to output the microwave at 70% of the normal output.

Finally, the cooling time is 10 minutes, the normal output time is characterized in that 20 minutes.

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 after the cooling time has elapsed according to the present invention, and FIG. It is a diagram showing.

The overheat prevention method of the microwave oven according to the present invention is to set the cooling time required to sufficiently cool the inside of the cooking chamber after the end of the previous cooking by controlling the output at the start of the current cooking in accordance with the time difference from the previous cooking end time, As shown in FIG. 2, when driving starts according to a cooking condition set by a first user (S10), a time difference between a previous cooking end time and a 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 confirmed, it is determined whether the time difference has passed the cooling time by comparing the time difference with the preset cooling time (S30).

In this case, when the time difference between the previous cooking end time and the current cooking start time passes the cooling time, as shown in FIG. It is determined whether the normal output time has elapsed (S100), and when the normal output time has elapsed, the drive is then performed with a variable output (S110).

In the embodiment according to the present invention, the normal output means driving at 100% output, and the low output described below is a preset output, which is less than the normal output, preferably 70 of the normal output. Means%.

In addition, the normal output time means a time for driving to a normal output after the start of cooking, and the variable output time means a time in which the normal output and the low output are repeatedly performed for a predetermined time.

On the other hand, when the time difference between the previous cooking end time and the current cooking start time has not passed the cooling time, that is, when the current cooking is started before the cooling time has elapsed, as shown in FIG. )do.

In this way, if the current cooking is started before the cooling time elapses and is driven at a low output, it is continuously determined whether the above cooling time has elapsed (S50). , Drive to normal output (S60).

This means that when driving at low power, the drive is driven at low power only until the cooling time has elapsed, and at normal power after the cooling time has elapsed. Therefore, the driving of the normal output before the cooling time has elapsed is to prevent the inside of the cooking chamber from overheating.

In addition, although the embodiment of the present invention proposes to drive at a low output of a constant output during the cooling time, the present invention is not limited thereto, and the low output may be varied, that is, increased every time a certain time passes. Therefore, the low power is gradually increased every time a certain time of the cooling time elapses, and the drive can be driven to the normal output at the end of the cooling time.

In addition, it is driven at a low output and a normal output, and it is determined whether the normal output time has elapsed (S70). At this time, when the normal output time has elapsed, it is driven at a variable output (S80).

That is, the normal output is made during the preset normal output time, and the normal output time includes not only the time driven by the normal output but also the time driven by the low output. Therefore, since the time is counted from the start of driving, when cooking is started before the cooling time has elapsed, it includes the time driven at low output as described above, and when the normal output time elapses, the time is driven at variable output.

Therefore, as shown in FIG. 4, it is preferable whether the current cooking starts after the cooling time has elapsed and is driven at a normal output, or whether the current cooking starts with low power and has first been driven at a low output before the cooling time has elapsed. When 20 minutes have elapsed since the start of the preset cooking, the drive is driven from the normal output to the variable output.

On the other hand, during the variable output time it is repeatedly driven for a constant time to the normal output and low output.

For example, if the current cooking is started 5 minutes before the cooling time and the normal output time is set to 20 minutes, the drive will run at low power for the first 5 minutes and at normal power for the remaining 15 minutes, which will result in normal 20 minutes of normal operation. The output time has elapsed. In this way, when the normal output time has elapsed, the output is driven with a variable output, and the low output and the normal output are repeatedly performed at 10 minute intervals.

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, according to the time difference between the previous cooking end time and the current cooking start time can control the output of the current cooking start to prevent overheating of the microwave oven.

Claims (7)

A first step of checking a time difference between the previous cooking end time and the current cooking start time after checking a previous cooking end time and a current cooking start time; And And determining whether the time difference passes a predetermined cooling time, and if the time difference does not pass the cooling time, a second step of driving the microwave oven at a low output. . The microwave oven according to claim 1, wherein the second step determines whether the cooling time has elapsed while the microwave oven is driven at a low output, and when the cooling time has elapsed, the microwave oven is driven at a normal output power. How to prevent overheating The method of claim 2, wherein the second step is to determine whether a predetermined normal output time has elapsed while the microwave oven is operating at a normal output, and when the normal output time has elapsed, repeatedly outputs a low output and a normal output every predetermined time. Overheating prevention method of the microwave oven, characterized in that for driving. The method of claim 1, wherein the second step increases the output of the microwave oven every time a predetermined time elapses until the cooling time elapses. 2. The method of claim 1, wherein said second step outputs said microwave oven at 70% of normal power. The method of claim 1, wherein the cooling time is 10 minutes. 4. The method for preventing overheating of a microwave oven according to claim 3, wherein the normal output time is 20 minutes.

Images