| 摘要 |
PURPOSE:To make it possible to use the cooker at normal temperature by means of the structure combining an infrared sensor and a chopper impeller made of an electrical insulator and thereby reducing induced noise and radio wave noise being synchronized with the chopping frequency. CONSTITUTION:When chopper impeller 10 is rotated in the neighborhood of sensor 15, noise component Nc due to the commercial power supply synchronized with the rotation of the impeller appears. It is considered that the motion of the impeller brings about electromagnetic variation. When consideration is focused on open hole 9, since it is possible to realize a condition that there is little variation in electromagnetic conditions between the condition of air at the time the hole is open and the case where there is impeller 10 at the time when the hole is closed, it is considered that this is due to the decrease in the amount of modulation at the noise chopper frequency. To satisfy this condition, it is effective to use an insulator. If high-frequency noise is taken into consideration, it is more effective to select one with a small dielectric constant and dielectric loss. |
