PURPOSE: To prevent increase in contact resistance over a prescribed wide load condition from a prescribed very small load, and improve contact reliability by inclining a moving piece support hole in a prescribed range, and making a movable contact point perform moving operation in a prescribed range.

CONSTITUTION: An inclined support hole 11 in which a movable contactor 7 is installed, has a support hole inclination of 5° to 30°, and an angle 16 is adjusted so that a difference (a movable contact point moving width 15) between a bottom part and an upper part of the hole 11 becomes 0.2 to 3min. Therefore, when a movable contact point 8 and a fixed contact point 6 contact each other, the contactor 7 on which the contact point 8 is installed, operates along the inclined support hole 11 of a moving piece 4, and produces a sliding effect to the contact point. When the contact point 8 slides on the contact point 6, most of a sticking material on a contact point contact surface is removed, and increase in contact resistance is prevented over a wide load condition of about 5A from a very small load of about DC 5V several mA, and contact reliability can be improved.