| 摘要 |
PURPOSE:To improve the extent of breaking performance in the same diameter of a windmill electrode by optimizing the width of a hollow groove of the windmill electrode to a breaking current required. CONSTITUTION:A recess part 4 is installed in the central part of a plane part 1 with a contact function. A taper part 2 has a current breaking function. Plural pieces of hollow grooves 3 extending in both radial and circumferential components are formed in the plane part 1 and the taper part 2. In this constitution aforesaid, when a pair of windmill electrodes in a state of contact with each other is separated from each other, an arc is produced in the plane part 1, and this arc is rotated on a surface of the windmill electrode by the groove 3. Size of this rotational speed is related to breaking performance, and there is an optimum value in groove width L of the groove 3. Consequently, the range of width L (mm) of this groove 3 is adjusted to the value in an equation whereby breaking capacity is improvable. In the equation, it is set to I=rated breaking currentX(1+DC content)kA. |
