A wiper support shaft supports a wiper, which wipes a windshield glass. The wiper support shaft projects outward through an opening of a cowl louver that is placed on a vehicle front side of the windshield glass. A four-bar linkage drives the wiper support shaft to move the wiper support shaft in the opening of the cowl louver in such a manner that a wiping range of the wiper, which is installed to the wiper support shaft, changes on the windshield glass. A covering member is supported by the wiper support shaft at a location inside the cowl louver to limit direct viewing of the four-bar linkage through the opening of the cowl louver.