Polishing apparatus and method therefor

A polishing method of polishing a top surface of a workpiece using a polishing apparatus, the polishing method comprising:

• a first step of mounting the workpiece on an upper surface of a support base in a first position;
• a second step of mounting sandpaper to a leading end portion of a polishing jig, pressing the sandpaper against the workpiece while rotating the polishing jig, and moving the sandpaper along the top surface of the workpiece;
• a third step of mounting a polishing brush to the leading end portion of the polishing jig, pressing the polishing brush against the workpiece while rotating the polishing jig, and moving the polishing brush along the top surface of the workpiece, wherein
• the polishing apparatus comprising:
• the support base attached to a base, the support base configured with the upper surface for supporting the workpiece horizontally in the first position;
• a lifter provided at a central portion of the support base configured to lower the workpiece onto the upper surface and lift the workpiece off of the upper surface;
• a machining head supported to independently move in two intersecting directions parallel to the upper surface of the support base;
• a machining head moving device that allows the machining head to independently move in the two intersecting directions;
• the polishing jig supported by the machining head to freely move in a direction perpendicular to the upper surface of the support base;
• a polishing member comprising the sandpaper or the polishing brush is mounted on the leading end portion of the polishing jig;
• a polishing jig moving device that moves the polishing jig in a direction perpendicular to the upper surface of the support base and is capable of pressing the polishing member against the workpiece;
• a polishing jig rotating device that is capable of rotating the polishing jig about an axis center perpendicular to the upper surface of the support base;
• wherein the upper surface of the support base is configured to support the workpiece horizontally in the second position wherein the second position is an angular rotation of the first position about a vertical axis, and
• wherein the top surface of the workpiece is polished by the polishing member in the first position, and wherein again the top surface of the workpiece is polished by the polishing member after the workpiece is rotated to be supported in the second position.