Abstract: An electric vehicle drive system includes an electric-vehicle power conversion device, and an earth ground switch that is a triple-pole single-throw switch having a switching contact unit. The electric-vehicle power conversion device includes a smoothing circuit unit that includes a filter capacitor that receives and stores therein power supplied from an overhead wire, an inverter that converts a DC voltage of the smoothing circuit unit into an AC voltage to drive an electric motor, and a brake chopper circuit that consumes excess power, which cannot be returned toward the overhead wire. A brake resistance in the brake chopper circuit is connected to the switching contact unit. When the switching contact unit is closed, the brake resistance is electrically connected between the positive electrode and the negative electrode of the filter capacitor.

Abstract: A door engagement device for an elevator according to the present invention is configured in such a manner that biasing-force applying/changing means applies a turning preventing force for preventing turning of a lever main body and changes a direction of a biasing force to a direction of an anti-turning preventing force to the lever main body by action of turning guiding means with movement of a car door. Accordingly, an engagement-mechanism driving device can be driven with a reduced space at low cost.

Abstract: There is obtained an energy storage mechanism, for a switching device, that has a structure requiring no high-accuracy components and can perform release of driving-power transmission and re-engagement.