KR101233244B1 - Circuit for operating of microwave oven - Google Patents

Abstract

The present invention relates to a driving circuit of a microwave oven, and in particular, when a door is opened by detecting a door opening of a microwave oven, a convection heater or a top heater and a power switch provided in a multi-function microwave oven through a relay. The present invention relates to a driving circuit of a microwave oven that contributes to the prevention of safety accidents by constructing a circuit that directly cuts off.

Microwave Oven, Drive Circuit, Relay, Interlock Switch

Description

CIRCUIT FOR OPERATING OF MICROWAVE OVEN}

1 is a view for explaining a driving circuit of a conventional microwave oven.

2 is a view for explaining a driving circuit of the microwave oven according to the present invention.

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

10: first interlock switch

20: high voltage transformer

30: second interlock switch

40: convection heater

50: top heater

60: door open monitoring switch

70: PCB

71: relay

The present invention relates to a driving circuit of a microwave oven, and more particularly, to detect a door opening of a microwave oven, and when a door is opened, a convection heater or a top heater and a power switch provided in a microwave oven. The present invention relates to a driving circuit of a microwave oven that contributes to the prevention of safety accidents by configuring a circuit that is directly cut off through a relay.

1 is a view for explaining a driving circuit of a conventional microwave oven.

In general, a microwave oven is a home appliance that is equipped with a magnetron that generates a high frequency to quickly cook food, and is composed of a plurality of relays, a microcomputer capable of controlling it, and a plurality of switches. Configure this to work smoothly.

A conventional microwave oven is provided with a fan motor for hot air circulation inside the cooking chamber, a tray motor installed at the bottom of the cooking chamber to rotate a tray on which the food is placed, and a lamp for lighting inside the cooking chamber, as shown in FIG. 1. It has a PCB with a number of relays and door open monitoring switches to control the operation of these motors and lamps. In addition, according to the control signal of the PCB is provided with a relay for applying or interrupting the power applied to the high voltage transformer described later.

In particular, in recent years, a commercial microwave oven equipped with a magnetron and a heater are installed on the market. The microwave oven includes a grill function using a heater and a microwave oven function in which only the magnetron is operated.

Meanwhile, a high voltage transformer (HVT) for boosting the high voltage required to drive the magnetron by receiving commercial power is installed, and an interlock switch for switching each circuit is installed. It prevents component damage due to overheating of high voltage transformer and switches according to opening / closing of door to change the contact point to supply and cut off power.

In addition, the temperature control means, such as a thermostat for shutting off the power when the temperature inside the cooking chamber is above a certain temperature is further provided.

Such a microwave oven has a door open monitoring switch that detects the opening of the door of the microwave oven in preparation for the risk of a safety accident when the microwave oven is driven. When the door of the microwave oven is detected as open, the microwave oven transmits a door open signal to the microcomputer. This convection heater, top heater, and power supply are shut off to prevent safety accidents.

However, such a conventional microwave oven is installed in a complicated structure by relays and switches, which are installed at the rear end thereof so as to control operations such as a convection heater, a top heater, and a power supply. The addition of a relay for the power control of the high-voltage transformer was the cause of the overall complexity of the microwave oven and increased production costs.

The present invention has been made to solve the problems of the prior art as described above, when a door is opened by detecting a door opening of a microwave oven, a convection heater or a top heater and a power source provided in a multi-function microwave oven. By constructing a circuit that directly cuts off the switch through a relay, it provides a driving circuit of a microwave oven that contributes to the prevention of safety accidents.

The present invention for achieving the above object is a first interlock switch for applying a commercial power; A high voltage transformer receiving commercial power through the first interlock switch to boost a high voltage necessary for driving the magnetron to cook food in the cooking chamber; A second interlock switch installed at a rear end of the high voltage transformer to turn on / off commercial power applied to the high voltage transformer; A convection heater and a top heater for cooking food in the cooking chamber and circulating hot air; A door open monitoring switch that monitors whether the microwave oven door is opened and shuts off operations of the convection heater, the top heater, and the second interlock switch when the door is opened; And a microcomputer for supplying commercial power to the microwave oven by a user's key operation and controlling driving of the first interlock switch, the second interlock switch, the high voltage transformer, and the heater.

In the present invention, the second interlock switch is configured as a power relay for turning on / off commercial power applied to the high voltage transformer.

In the present invention, the door open monitoring switch is configured by connecting the heater and the second interlock switch by a relay to block driving of the convection heater, the top heater and the second interlock switch when the microwave oven door is opened.

As described above, the present invention by contributing to the prevention of safety accidents by detecting a door opening of the microwave oven by configuring a circuit to directly cut off the convection heater or top heater and the power switch provided in the multi-function microwave oven through the relay Provided is a driving circuit of a microwave oven.

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

2 is a view for explaining a driving circuit of the microwave oven according to the present invention.

As shown in FIG. 2, the present invention provides a first interlock switch 10 to which commercial power is applied, and commercial power is applied through the first interlock switch 10 to boost the voltage to a high voltage necessary for driving the magnetron. And a second interlock switch 30 installed at a rear end of the high voltage transformer 20 to turn on / off commercial power applied to the high voltage transformer 20. ), The convection heater 40 and the top heater 50 for cooking and circulating hot air and hot air circulation, and the convection heater 40 and the top heater 50 when the door is opened by monitoring whether the microwave oven door is opened or closed. And the door open monitoring switch 60 for blocking the operation of the second interlock switch 30, and supplying commercial power to the microwave oven by the user's key operation, and the first interlock switch 10 and the second interlock switch 30. Interlock switch (30) And a microcomputer (not shown) for controlling the driving of the high voltage transformer 20 and the heaters 40 and 50.

Of course, the microwave oven is connected in parallel with the high voltage transformer 20 and connected in parallel with the fan motor FM and the fan motor FM for cooling the heat generated when the high voltage transformer 20 is driven, The tray motor for rotating the tray on which the food to be installed is placed and the oven lamp OL for illuminating the inside of the cooking chamber are connected to the first interlock switch 10.

Here, the second interlock switch 30 is configured as a power relay for turning on / off commercial power applied to the high voltage transformer.

In addition, the door open monitoring switch 60 is the heater 40, 50 to block the driving of the convection heater 40, the top heater 50 and the second interlock switch 30 when the microwave oven door is opened. And the second interlock switch 30 are connected to the door open monitoring switch 60 and the relay 71.

In the driving process of the microwave oven according to the present invention, when a user selects a function of cooking food through a key panel, the first interlock switch 10 is turned on and commercial power is applied through a fuse. In addition, the microcomputer recognizes the switching state of the door open monitoring switch 60 and checks whether the door is in a closed state. If the door is in a closed state, the microcomputer is connected to the high voltage transformer 20 side and is commercially available in the high voltage transformer 20. Power will be applied.

In addition, the PCB 70 turns on the second interlock switch 30 to allow commercial power to be applied to the high voltage transformer 20. Accordingly, the magnetron may drive the high voltage transformer 20 to which the commercial power is applied. The food inside the cooking chamber is cooked by increasing the voltage to a high voltage so that it can

In this case, the oven lamp OL and the fan motor FM connected to the second switch SW2 are turned on by the control signal of the PCB 70 to illuminate the inside of the cooking chamber, and the hot air circulation is performed.

Therefore, when cooking food using the high-voltage transformer 20, the commercial power is applied to the high-voltage transformer 20 by the first in-lock switch 10 and the second inter-lock switch 30, the door Is opened, the high-voltage transformer 20 is not driven by turning off through the relay 71 associated with the convection heater, the top heater, and the second interlock switch in the door open monitoring switch 60. do.

Meanwhile, when cooking food by driving an internal heater without driving the high voltage transformer 20, even if the first interlock switch 10 is connected to the high voltage transformer 20, the microcomputer of the PCB 10 is relayed. By turning off the second interlock switch 30, the commercial power is not applied to the high voltage transformer 20, while the heater, fan motor FM, grill motor GM, etc. are driven through the relay. By doing so, food cooking using the grill heater can be performed.

Therefore, as described above, the second interlock switch 30 is installed at the rear end of the high-voltage transformer 20, and the door open monitoring switch 60 switched according to opening and closing of the door includes the second interlock switch and the convection heater; By connecting with a top heater, the safety of the device can be achieved through the door open monitoring switch.

As such, the present invention contributes to the prevention of safety accidents by constructing a circuit that directly detects the door opening of the microwave oven and directly closes the convection heater or the top heater and the power switch provided in the multi-function microwave oven when the door is opened. .

As described above, the present invention is to prevent the safety accident by configuring a circuit that directly detects the door opening of the microwave oven, the convection heater or top heater and the power switch provided in the multi-function microwave oven through the relay when the door is opened. There is an advantage to contribute.

Claims (3)

A first interlock switch for applying commercial power; A high voltage transformer receiving commercial power through the first interlock switch to boost a high voltage necessary for driving the magnetron to cook food in the cooking chamber; A second interlock switch installed at a rear end of the high voltage transformer to turn on / off commercial power applied to the high voltage transformer; A convection heater and a top heater for cooking food in the cooking chamber and circulating hot air; A door open monitoring switch that monitors whether the microwave oven door is opened and shuts off operations of the convection heater, the top heater, and the second interlock switch when the door is opened; A microcomputer that supplies commercial power to a microwave oven by a user's key operation and controls driving of the first interlock switch, the second interlock switch, the high voltage transformer, and the heater; A driving circuit of a microwave oven comprising a. The method of claim 1, The second interlock switch is a driving circuit of the microwave oven, characterized in that configured as a power relay for turning on / off the commercial power applied to the high-voltage transformer. The method of claim 1, The door open monitoring switch is configured by connecting the convection heater, the top heater, and the second interlock switch by a relay to block driving of the convection heater, the top heater, and the second interlock switch when the microwave oven door is opened. Microwave drive circuit.

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