Patent ID: 8004781
Filing Date: 2011-08-23
Classification: G11B

Abstract:
1. A magnetic transfer apparatus for magnetically transferring patterned magnetic information of a master disc to a double-sided slave disc by applying a magnetic field to the master disc in contact with the double-sided slave disc, said magnetic transfer apparatus comprising: a first disc holder device having a recess for holding a first master disc and a double-sided slave disc in contact with each other therein, said first master disc having a spindle hole greater than a spindle hole of said double-sided slave disc; a second disc holder device having a recess for holding a second master disc, said second master disc having a spindle hole with a same diameter as the spindle hole of said first master disc; a shifting device for shifting said first disc holder device and said second disc holder device relatively toward each other to form an air-tight chamber between said recesses of said first disc holder device and said second disc holder device and away from each other to open said air-tight chamber, said double-sided slave disc being brought into contact with said second master disc so as to be sandwiched between said first master disc and said second master disc when said air-tight chamber is formed between said recesses of said first disc holder device and said second disc holder device; an air supply device for supplying air into a space formed above a peripheral portion of said double-sided slave disc beyond said second master disc; and a control device for controlling said air supply device to supply air into said space above said peripheral portion of said double-sided slave disc beyond said second master disc at least either during formation of said air-tight chamber or during opening of said air-tight chamber, wherein air is supplied at a supply rate per unit of time different than a supply rate during formation of said air-tight chamber and a supply rate during opening of said air-tight chamber.