Method and apparatus for vibration polishing vehicle wheel

A method for polishing a vehicle wheel having a three-dimensional shape, the vehicle wheel including a disc-shaped disc portion in which a plurality of window holes are provided and a cylindrical rim portion that is located around the disc portion, the method comprising: oscillating a bottomed cylindrical polishing medium storage tank to vibrate the polishing medium storage tank, a polishing medium being stored in the polishing medium storage tank; causing the polishing medium in the polishing medium storage tank to flow in a vortex manner; generating a convection in which the polishing medium flows downward in a center portion of the vortex while flowing upward in an outer circumferential portion or a convection in which the polishing medium flows upward in the center portion of the vortex while flowing downward in the outer circumferential portion; connecting a support shaft from a back side of the vehicle wheel; transversely situating the vehicle wheel with a rear surface of the disc portion oriented upward; dipping the vehicle wheel in the polishing medium of the polishing medium storage tank such that the rim portion is disposed between an upward flow and a downward flow of the polishing medium by the convection; causing the polishing medium to flow outside and inside the vehicle wheel; causing the polishing medium to flow so as to pass through the window holes of the disc portion; and vibrating the vehicle wheel through the support shaft to vibration polishing the vehicle wheel.