Abstract: A high voltage transformer for a microwave oven includes a core, and primary and secondary coils. An insulation molding part encloses at least a part of the secondary coil and has a sensor accommodation portion formed therein. A temperature sensor is accommodated in the sensor accommodating portion for detecting temperature of the secondary coil. The sensor accommodating portion can be formed inside of the insulation molding part together with the temperature sensor, or formed outside of the insulation molding part in a pocket shape. With either configuration, the temperature sensor can be positioned at the correct sensor position, thereby improving the detecting accuracy of the temperature sensor. In addition, it is easy to repair and/or replace the temperature sensor.

Abstract: A method for forming a resin molding on a coil of a transformer is disclosed. The method comprises the steps of inserting a coil into an auxiliary spacing apparatus, inserting the auxiliary spacing apparatus into a mold, and forming a resin molding for the auxiliary spacing apparatus with the coil by putting a resin into the mold. According to the methods, the coil is not damaged and a resin molding is formed with an uniform thickness.

Abstract: A transformer for a microwave oven capable of preventing quality deterioration thereof due to damaged insulating paper, includes a first core having a coil inserting section having one open side; a plurality of coils sequentially inserted into the coil inserting section in an inter-electrically insulated state; a second core coupled,to the first core, and for covering the open side of the coil inserting section; and a resin molding section formed to cover the whole area of the plurality of coils.

Abstract: A method for forming a resin molding on a coil of a transformer is disclosed. The method comprises the steps of inserting a coil into an auxiliary spacing apparatus, inserting the auxiliary spacing apparatus into a mold, and forming a resin molding for the auxiliary spacing apparatus with the coil by putting a resin into the mold. According to the methods, the coil is not damaged and a resin molding is formed with an uniform thickness.

Abstract: In the microwave oven having a high voltage driving part with a high voltage transformer, a switching unit applies electric power to the high voltage driving part. In the switching unit, when switched on, an operational contact firstly comes in contact with a first contact coupled with a PTC thermistor and secondly with a second contact after a given time period, and a driving unit generates driving force and turns on/off the switching unit. Since the switching unit and driving unit may be simply installed to effectively eliminate the inrush current, assembly and work efficiencies are improved according to a simpler wiring process, and also, the total manufacturing cost for the microwave oven is reduced.