KR19980019965A - microwave - Google Patents

Abstract

The present invention relates to a microwave oven, and more particularly, to a microwave oven capable of preventing a surge current generated during driving.

To this end, the present invention is the main body is provided with a cooking chamber that is accommodated in the food is cooked therein, a high-voltage transformer for boosting the commercial AC power to a predetermined size, is driven by applying a voltage boosted by the high-voltage transformer to irradiate the high frequency inside the cooking chamber In the microwave oven equipped with a magnetron for heating and cooking food, it is installed in the intermediate stage between the commercial AC power supply and the high-voltage transformer (HVT) when the surge current flows to block the surge current to the high-voltage transformer (HVT) It characterized in that it comprises a surge resistor (R) to prevent the application to.

Description

microwave

The present invention relates to a microwave oven, and more particularly, to a microwave oven capable of preventing a surge current generated during driving.

In general, a microwave oven is a cooker that applies the principle that food in a metal case generates heat by its own molecular motion using electromagnetic waves of approximately 2450 MHz. In such a microwave, radio waves of about 2450 MHz are oscillated in the magnetron and induced into the case, 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 per second due to high frequency radio waves, food molecules are severely collided with each other, causing frictional heat to heat the food.

As shown in FIG. 1, the microwave oven includes a cooking chamber 11 in which food is stored and cooked inside the cabinet 10, and a component for radiating high frequency into the cooking chamber is accommodated in the side of the cooking chamber 11. The electrical equipment room 12 is installed. A door 13 is installed on the front surface of the cooking chamber 11 to open and close the cooking chamber 11. In addition, the electronics compartment 12 is provided with a magnetron 14 for irradiating high frequency and a high voltage transformer 15 for supplying a high voltage to the magnetron 14, and a cooling fan at the rear of the electronics compartment 12 for cooling the components. 16 is installed. Meanwhile, a bracket 17 supporting a fan motor for driving the cooling fan 16 is provided, and the choke board 20 is mounted on the upper end of the bracket 17. The choke substrate 20 is provided with a noise filter for removing noise in the commercial AC power supply and a cement resistor which can protect various electronic components by cutting off the inrush current of the commercial AC power.

On the other hand, in such a conventional microwave oven, the cement resistor is generally used for electric power in the winding navigator and is formed by filling a cement wire with a metal resistance wire in a case by spiral winding. At this time, the cement is to prevent the oxidation of the resistance line by the heating. This cement resistance is used in the primary side of the commercial AC power supply and the high voltage transformer in order to prevent damage and malfunction of components caused by rush current or surge current caused by accidental accident during driving of high voltage transformer and magnetron. It is connected so as to block the inrush current applied to the high voltage transformer.

However, in the microwave oven using the conventional cement resistance, the cement resistance is not a complete protection against the surge current generated in the high-voltage transformer during the operation of the microwave oven, often breakage and high heat caused by the surge current. As a result, it was unable to perform a stable surge current blocking operation. In addition, the cement resistance is large because it is formed by spirally winding the metal resistance wire by a predetermined length to obtain a predetermined resistance value, and thus occupies a wide range in the chalk substrate.

Accordingly, the present invention has been made to solve the above-mentioned drawbacks of the prior art, and its purpose is to cut off the surge current generated in the high voltage transformer during the operation of the microwave oven, and to perform a stable operation, and also have a miniaturized surge resistance. It is to provide a microwave.

1 is a perspective view showing the configuration of a general microwave oven.

2 is a circuit diagram showing a circuit configuration of a microwave oven according to the present invention.

Explanation of symbols on the main parts of the drawings

R: Surge resistance, C: Coil, RY1: Relay switch

In order to achieve the above object, the microwave oven according to the present invention is provided with a main body having a cooking compartment in which food is stored and cooked therein, a high voltage transformer for boosting a commercial AC power to a predetermined size, and receiving a voltage boosted by the high voltage transformer. In a microwave oven having a magnetron that is driven and irradiated with a high frequency inside the cooking chamber to heat and cook food, is installed in the intermediate stage of the commercial AC power supply and the high-voltage transformer when the surge current flows to block the surge current It is characterized in that it comprises a surge resistance to prevent the application to the high-voltage transformer.

Hereinafter, the configuration and the effect according to the preferred embodiment of the present invention will be described in detail. First, as shown in FIG. 1, the microwave oven according to the present invention is provided with a cooking chamber 11 in which food is stored and cooked inside the cabinet 10, and irradiated with a cooking chamber at a high frequency toward the side of the cooking chamber 11. The electrical equipment compartment 12 which accommodates components for this is provided. A door 12 is installed on the front of the cooking chamber 11 to open and close the cooking chamber. In addition, the electronics compartment 12 is provided with a magnetron 14 for irradiating high frequency and a high voltage transformer 15 for supplying a high voltage to the magnetron 14, and a cooling fan at the rear of the electronics compartment 12 for cooling the components. 16 is installed. A tray in which food is placed is provided inside the cooking chamber, not shown, and at the bottom thereof, a tray motor is axially coupled to the tray to rotate the tray so that the high frequency of the magnetron is evenly distributed during cooking.

In addition, the circuit configuration of the microwave oven according to the present invention is as shown in FIG.

A noise filter 21 which removes the noise in the commercial AC power supply and the commercial AC power supply, and provides a stable commercial AC power supply as a driving power to various electrical components connected to the rear stage, and filtered by the noise filter 21. The high-voltage transformer (HVT) and the high voltage boosted by the high-voltage transformer (HVT) for receiving a commercial AC power is supplied to the tray motor (TM) and fan motor (FM), the commercial AC power is boosted to a predetermined size A magnetron 14 that is applied to generate high frequency radiation to be irradiated into the cooking chamber, a surge resistor R connected to an intermediate end of the high voltage transformer HVT and the commercial AC power supply, and a coil connected in parallel with the surge resistor R. And a relay switch RY1 for disconnecting one end of the commercial AC power applied to the high voltage transformer HVT according to whether or not electricity supply to (C) is performed.

Referring to the operation of the microwave oven according to the present invention having such a configuration as follows. First, when it is determined that a start command is input by the user while the commercial AC power is applied, the commercial AC power is applied to the primary side of the high-voltage transformer (HVT) and boosted to a predetermined size to be connected to the secondary side. It is applied to the magnetron 14. In this case, the magnetron 14 heats and cooks food by irradiating the inside of the cooking chamber with a high frequency having a predetermined frequency. In addition, by simultaneously rotating the tray by the drive of the tray motor (TM), the high frequency radiated into the cooking chamber is evenly distributed in the food to ensure uniform cooking, and the cooling fan 16 is driven to drive the magnetron 14 and the high pressure transformer. The heat generated by the driving of the (HVT) is cooled.

On the other hand, upon initial application of the commercial AC power, the commercial AC power flows to the surge resistance (R) side to cut off the surge current, and then supply the driving power to the primary side of the high voltage transformer (HVT) to perform a stable operation. After the elapse of time, power is applied to the coil C to turn on the relay switch RY1, so that the commercial AC power is applied to the primary side of the high voltage transformer HVT via the relay switch Ry1. Accordingly, the magnetron 14 heats and cooks food by applying high voltage boosted by the high voltage transformer (HVT) to generate high frequency and irradiate the inside of the cooking chamber.

In addition, when the coil C is disconnected due to an accident, the relay switch RY1 is not operated and is always kept open. Therefore, the AC flows to the high voltage transformer (HVT) and the surge resistance (R). At this time, when the current flows, for example, about 4A, the surge resistance is opened. Therefore, the surge current is blocked from flowing through the high voltage transformer HVT to prevent damage to the high voltage transformer HVT and the magnetron 14. Such surge resistors (R) are generally carbonaceous resistors, and as a resistor, silicon powder or talc powder is mixed with graphite powder, and phenolic synthetic resin is molded as a binder and molded outward with synthetic resin such as bakelite. Compared to cement resistance, the same electric power is much smaller and can be used closely in small sets because of the close resistance between them.

As described above, a stable operation can be performed by effectively blocking the surge current by the microwave oven according to the present invention, and the surge resistance used to block the surge current is smaller in size than the conventional cement resistor. Miniaturization can be achieved.

Claims (1)

The main body is provided with a cooking compartment in which food is stored and cooked therein, a high voltage transformer for boosting a commercial AC power supply to a predetermined size, and is driven by being supplied with a voltage boosted by the high voltage transformer to irradiate high frequency into the cooking chamber to heat and cook food. In a microwave oven having a magnetron, it is installed in the intermediate stage of the commercial AC power supply and the high voltage transformer (HVT) to prevent the surge current from being applied to the high voltage transformer (HVT) when the surge current is introduced. Microwave oven comprising a surge resistance (R).