Abstract: Disclosed is a drum washing machine having ball balancers for rapidly reducing the vibration of a drum. The drum washing machine includes a drum rotatably installed so as to wash or dehydrate laundry; and balancers, each including a plurality of masses; a housing provided with a race having a rectangular section, on which the masses move in a circumferential direction; and a fluid filling the inside of the race for reducing noise caused by the circumferential movement of the masses. The race has a rectangular section, corner portions of which are rounded, and a value obtained by dividing the radius of the corner portions by the radius of the masses is between 0.4 and 0.9 so as to effectively reduce the vibration of the drum. The drum washing machine effectively reduces the vibration of the drum while using a small amount of the fluid.

Abstract: A cooking container designed to brown and scorch slightly both sides of food at the same time, and a microwave oven having such a cooking container. This cooking container includes a pan body and a lid, each including a heating part generating heat using microwaves and a heat transfer part transferring heat from the heating part to food. The body of the container has a first cooking part covered with the lid, and a second cooking part having an open top. A plurality of embossments are provided on each of the first cooking part and the lid while being regularly spaced apart from each other, and so both sides of sliced bread laid in the first cooking part are thus browned and scorched slightly during the process of cooking. The second cooking part is used for frying eggs. A coated layer is formed on the inside surface of each heat transfer part of the container, thus preventing a corrosion of the heat transfer part and a sticking of food to the heat transfer part.

Abstract: An electric cooker having an enhanced heat insulating property to improve heat efficiency. The electric cooker includes a cabinet, a cooking plate disposed at a top portion of the cabinet, a heating member to heat the cooking plate, at least one heat insulating member disposed below the heating member to prevent heat generated by the heating member from being transmitted downward, and a reflecting member to reflect thermal infrared lights generated from the heating member towards the heat insulating member.

Abstract: A composite cooking apparatus having a body, a heating unit, an induction heating unit, and an insulating plate. The heating unit is positioned in the body to generate heat used to heat food. The induction heating unit is positioned adjacent to the heating unit to generate a magnetic field to cook the food by induction heating. The insulating plate is positioned between the heating unit and the induction heating unit to prevent heat generated from the heating unit from being transmitted to the induction heating unit. Further, the insulating plate is provided with at least one heat reflecting layer to reflect the heat generated from the heating unit.

Abstract: A composite cooking apparatus having a body, a heating unit, and an induction heating unit. The heating unit is positioned in the body to generate heat used to heat food. The induction heating unit is positioned adjacent to the heating unit to generate a magnetic field to cook the food by induction heating. The induction heating unit has at least one wire, a coating of which is exposed to an electron beam to strengthen a heat resistance thereof.

Abstract: A cooker having an air cleaning unit to clean the air around the cooker. The air cleaning unit has an air sucking port provided on a top wall of a casing, and an air discharging port provided at a front of an upper wall of a cooking cavity. An air passage is defined between the air sucking port and the air discharging port. A filter unit and a blowing fan are installed in the air passage. The air sucking port is integrated into a cover that hooks onto an edge of an opening that is formed on the top wall of the casing. A duct body defining the air passage is mounted on the upper wall of the cooking cavity. Guide grooves are provided at both sides of the inlet port so that the filter unit is slidably and removably fitted into the guide grooves.

Abstract: A cooking apparatus to improve heating efficiency and to quickly cook food. The cooking apparatus includes a heater provided at a tray receiving food to be cooked and having a pair of terminals to supply power to the heater, and a plurality of sockets provided at a rear wall of a cooking cavity. When the tray is placed on a pair of support rails of the cooking cavity and the terminals of the heater are inserted into one of the sockets, the tray is directly heated by the heater to cook the food. The heater includes a conductive film coated on a lower surface of the tray, and first and second electrodes connected to the conductive film to be opposed to each other and connected to the terminals. The conductive film and the tray are heated by current flowing through the conductive film between the first and second electrodes.

Abstract: An electric cooker having an enhanced heat insulating property to improve heat efficiency. The electric cooker includes a cabinet, a cooking plate disposed at a top portion of the cabinet, a heating member to heat the cooking plate, at least one heat insulating member disposed below the heating member to prevent heat generated by the heating member from being transmitted downward, and a reflecting member to reflect thermal infrared lights generated from the heating member towards the heat insulating member.

Abstract: A polymer-type humidity sensor for use in a microwave oven and which has a polymer structure which includes a rubber and a predetermined amount of carbon, and a pair of electric terminals connected to the polymer structure. The polymer-type humidity sensor of the present invention has a rapid response time, durability, excellent adherence to terminals, low hysteresis, and exhibits stability to exposures of high temperatures and high relative humidity.

Abstract: A cooking apparatus to improve heating efficiency and to quickly cook food. The cooking apparatus includes a heater provided at a tray receiving food to be cooked and having a pair of terminals to supply power to the heater, and a plurality of sockets provided at a rear wall of a cooking cavity. When the tray is placed on a pair of support rails of the cooking cavity and the terminals of the heater are inserted into one of the sockets, the tray is directly heated by the heater to cook the food. The heater includes a conductive film coated on a lower surface of the tray, and first and second electrodes connected to the conductive film to be opposed to each other and connected to the terminals. The conductive film and the tray are heated by current flowing through the conductive film between the first and second electrodes.

Abstract: A cooker having an air cleaning unit to clean the air around the cooker. The air cleaning unit has an air sucking port provided on a top wall of a casing, and an air discharging port provided at a front of an upper wall of a cooking cavity. An air passage is defined between the air sucking port and the air discharging port. A filter unit and a blowing fan are installed in the air passage. The air sucking port is integrated into a cover that hooks onto an edge of an opening that is formed on the top wall of the casing. A duct body defining the air passage is mounted on the upper wall of the cooking cavity. Guide grooves are provided at both sides of the inlet port so that the filter unit is slidably and removably fitted into the guide grooves.

Abstract: A cooking container designed to brown and scorch slightly both sides of food at the same time, and a microwave oven having such a cooking container. This cooking container includes a pan body and a lid, each including a heating part generating heat using microwaves and a heat transfer part transferring heat from the heating part to food. The body of the container has a first cooking part covered with the lid, and a second cooking part having an open top. A plurality of embossments are provided on each of the first cooking part and the lid while being regularly spaced apart from each other, and so both sides of sliced bread laid in the first cooking part are thus browned and scorched slightly during the process of cooking. The second cooking part is used for frying eggs. A coated layer is formed on the inside surface of each heat transfer part of the container, thus preventing a corrosion of the heat transfer part and a sticking of food to the heat transfer part.

Abstract: A polymer-type humidity sensor for use in a microwave oven and which has a polymer structure which comprises a rubber and a predetermined amount of carbon, and a pair of electric terminals connected to the polymer structure. The polymer-type humidity sensor of the present invention has a rapid response time, durability, excellent adherence to terminals, low hysteresis, and exhibit stability to exposures of high temperatures and high relative humidity.

Abstract: A microwave oven having a wave distributing device. A motor-operated rotor is installed inside a cooking cavity to distribute high-frequency electromagnetic waves (“microwaves”) generated by the oscillation of a magnetron. The wave distributing device includes a rotation trace limiter which limits a rotation trace of the rotor within a predetermined range. The rotation trace limiter includes stoppers which limit the rotation of the rotor, or a cam mechanism unit which changes a movement of a motor shaft connecting the rotor to the motor. Accordingly, an optimum energy efficiency is achieved, thereby saving energy required during an operation of the microwave oven under a standard load. In addition, the amount of the microwaves reflected back to the magnetron during an operation under a no-load or a light load is reduced. Therefore, life expectancy of the magnetron and the overall operational reliability of the microwave oven are improved.

Abstract: A microwave oven having a wave distributing device. A motor-operated rotor is installed inside a cooking cavity to distribute high-frequency electromagnetic waves (“microwaves”) generated by the oscillation of a magnetron. The wave distributing device includes a rotation trace limiter which limits a rotation trace of the rotor within a predetermined range. The rotation trace limiter includes stoppers which limit the rotation of the rotor, or a cam mechanism unit which changes a movement of a motor shaft connecting the rotor to the motor. Accordingly, an optimum energy efficiency is achieved, thereby saving energy required during an operation of the microwave oven under a standard load. In addition, the amount of the microwaves reflected back to the magnetron during an operation under a no-load or a light load is reduced. Therefore, life expectancy of the magnetron and the overall operational reliability of the microwave oven are improved.

Abstract: A magnetron includes a positive polar section having a positive polar cylinder, a plurality of vanes arranged at equal distance to radially protrude from an inner wall to a predetermined radius of the positive polar cylinder and plural strip rings electrically connecting the alternately-disposed vanes among the plural vanes, and a negative polar section having by a filament having a radius smaller than the predetermined radius for emitting thermoelectron to be installed onto a center line of the positive polar cylinder. Respective vanes provide slanted plane or curved plane to allow the area of a plane facing with an adjacent vane to be wider than that of a planar plane parallel with the cylinder axial direction of the positive polar cylinder within the same height of the vanes, thereby increasing capacitance of a cavity resonator formed by adjacent vanes and inner wall of the positive polar cylinder to cut down materials applied and allow for small-sized fabrication.

Abstract: The magnetron driving control apparatus of a microwave oven and a method thereof by which voltage at output side of a high voltage transformer and voltage of a magnetron are detected by a first and second voltage detecting units and a cooking process status is discriminated according to changes of the voltage at the output side of the high voltage transformer and the voltage of the magnetron to control the driving of the magnetron, such that foodstuff is optimally cooked and an automatic cooking is performed without installment of high priced sensors to thereby reduce the manufacturing cost.

Abstract: A microwave oven includes a power cut-off safety switch which automatically cuts-off the supply of electric power to the oven if a housing panel is removed while the electric power supply cord is still plugged in. The switch is engaged by an extension of the housing panel which extends through a guide hole formed by another housing panel. The guide hole can have a non-planar shape to resist efforts to insert objects through the guide hole.

Abstract: A microwave oven includes an electric power supply shut-off mechanism for cutting off the supply of electric power when the housing is disassembled for repair while an electric power cord remains plugged into an electric outlet. A sensor in the form of a light sensitive semiconductor and/or a piezoelectric crystal senses when panels of the oven housing are removed and thereupon causes a controller to actuate a solenoid which deactivates a safety switch for cutting off the supply of electric current.

Abstract: A microwave oven includes a housing formed by relatively separable first and second panels. Electric switches are mounted on the first panel and are connected to respective wires of the power cord by the oven. Each switch includes a movable contact which moves away from a respective fixed contact when the panels are separated from one another, in order to automatically cut off the supply of electric power to the oven in the event that the worker forgets to unplug the power cord. When the panels are reconnected, the switches are automatically closed. Such automatic closing can be caused by magnetic force produced by magnets carried by the second panel. Alternatively, the automatic closing can be caused by screws carried by the second housing and which physically push respective movable contacts against their associated fixed contacts.