| 摘要 |
PURPOSE:To save an element of larger capacity than required by arranging an overheat protection element close to a stator coil and connecting the element between an AC power source and a constant-voltage part. CONSTITUTION:An overheat protection element 21 is arranged close enough to a stator coil 15 to detect an abnormal temperature thereof. An AC power source 23 is connected to a constant-voltage part 31 through a noise filter 28 and the terminals 21a and 21b of the overheat protection element 21 are connected to one bus bar 23a between the noise filter 28 and the constant-voltage part 31 for electric connection. When the overheat protection element is operated by heat generated by abnormality, such as lock, of the motor of this structure, the contacts in the element are not welded because an alternating current has been passed between the terminals of the element. Therefore, electric connection of the ends of the element is securely broken and a current to the coil is cut even if an element of larger capacity than required is not used. |
