Combination hood and microwave oven

A combination hood and microwave oven, including a power supply, an exhaust motor, a variable suction hole having a variable suction area, and a variable suction hole drive motor, comprising:

• a control unit controlling an operation of the microwave oven;
• an exhaust motor drive unit, connected to the control unit, to control an on and off operation of the exhaust motor and to control a rotational speed of the exhaust motor;
• and
• a variable suction hole adjusting unit, connected to the control unit, to control the suction area of the variable suction hole by changing a rotating direction of the variable suction hole drive motor.

A method to operate a combination hood and microwave oven, including an exhaust motor drive unit, to drive an exhaust motor, having first and second exhaust switches coupled to first and second relays, respectively, the first relay having normally open and normally closed contact points, and the second relay having normally open contact points, and a variable suction hole adjusting unit to rotate a variable suction hole drive motor in forward and reverse directions to open and close, respectively, a variable suction hole, comprising:

• turning the second exhaust switch on while the first exhaust switch is turned off thereby exciting the first relay and closing the normally open contact points of the first relay;
• supplying power to the exhaust motor, through the normally open contact points of the second relay, which are closed, and the normally closed contact points of the first relay which are closed, to rotate the exhaust motor at low speed;
• and
• supplying power to the variable suction hole adjusting unit to rotate the variable suction hole drive motor in reverse, thereby closing the variable suction hole.

A method to operate a combination hood and microwave oven, including an exhaust motor drive unit, to drive an exhaust motor, having first and second exhaust switches, coupled to first and second relays, respectively, the first relay having normally open and normally closed contact points, and the second relay having normally open contact points, and a variable suction hole adjusting unit to rotate a variable suction hole drive motor in forward and reverse directions to open and close, respectively, a variable suction hole, comprising:

• turning the first exhaust switch on while the second exhaust switch is turned on thereby exciting the first relay and closing the normally open contact points of the first relay;
• supplying power to the exhaust motor, through the normally open contact points of the first relay, which are closed;
• and
• supplying power to the variable suction hole adjusting unit to rotate the variable suction hole drive motor forward, thereby opening the variable suction hole.

A combination hood and microwave oven, including a power supply, an exhaust motor and a variable suction hole having a variable suction area, comprising:

• a control unit controlling an operation of the microwave oven;
• an exhaust motor drive unit, connected to the control unit, to control an on and off operation of the exhaust motor and to control a rotational speed of the exhaust motor;
• and
• a variable suction hole adjusting unit, connected to the control unit, to control the suction area of the variable suction hole according to the rotational speed of the exhaust motor.