Patent ID: 7420782

Claim:
A rotating disk storage device, comprising: a rotating disk recording medium; an actuator head suspension assembly including a head for reading data from said rotating disk recording medium; a casing main body including a first yoke area formed from a ferromagnetic material; a casing lid including a second yoke area formed from a ferromagnetic material and magnetically coupled to said first yoke area; a magnet disposed so as to be magnetically coupled to either said first yoke area or said second yoke area; a coil held in position on said actuator head suspension assembly and disposed in a yoke gap defined between said magnet and either said first yoke area or said second yoke area; an auxiliary yoke disposed so as to be magnetically coupled to one of said first yoke area and said second yoke area; and a connecting yoke magnetically coupling said auxiliary yoke to the other of said first yoke area and said second yoke area instead of, or together with, magnetically coupling said first yoke area to said second yoke area; wherein said magnet is disposed so as to be magnetically coupled to said auxiliary yoke; wherein the second yoke area includes a second yoke portion formed separate from said casing lid and magnetically coupled to a first yoke portion within said first yoke area.