Polishing system and method of control of same

Abstract

A polishing system and a method of control of the same enabling reliable transfer of the workpieces into and out of the system while maintaining the precision of polishing of the workpieces. Provision is made of a polishing apparatus 1, a first transfer apparatus 2, a second transfer apparatus 3, and a control apparatus 4. In the polishing apparatus 1, workpieces W held in m number of holding holes 14 formed in n number of carriers 14 are polished on their two surfaces by a lower platen 10 and an upper platen 19. The control apparatus 4 finds the revolution angle of the carriers 14 when the workpieces reach the desired thickness, makes the carriers revolve until the revolution angle of a whole multiple of 360.degree./n closest to the revolution angle found, and then makes the polishing apparatus 1 stop. Further, it finds the rotation angle of the carriers after stopping and makes mounters 24 and 34 of a loader 23 and unloader 33 rotate by exactly that rotation angle so as to transfer the workpieces W into and out from the carriers 14.