Abstract: A food weight sensing device for a microwave oven, which comprises a fixed electrode plate and a movable electrode plate which vary in overlapping area, according to a vertical movement of a movable spacer caused by the weight of a food to be measured. A capacitance signal indicative of the variation in overlapping area is converted into a frequency signal, so as to sense precisely the weight of food.

Abstract: A high frequency cooker which detects a sound generated upon boiling of a material to be heated in response to the material being heated and switch as to a cooking mode in response to the detected signal of that sound. The cooker comprises a heating section for heating a material to be heated, a sensor for detecting a sound generated from the material to be heated upon boiling of the material to be heated, and a control section for controlling the heating section in response to the detected sound. The cooker can sense the sound of the material to be heated and can switch automatically from a cooking mode to a warm mode even by only making a single function selection. An optimum cooking state of the food can be maintained, and unnecessary power loss can also be prevented.