Abstract: A beam damper for damping acoustic noise generated by an actuator of a disc drive. The beam damper is compressed between a portion of a housing of the disc drive and an actuator motor. The beam damper includes a substantially flat platform affixed to a selected one of the housing and an upper or lower pole of the actuator motor. A plurality of flex beams extend from the platform at a selected angle and contact the remaining one of the housing and the upper or lower pole to resiliently bias the housing with respect to the actuator motor. The beam damper is preferably formed from a sheet of ductile metal which is stamped to form the platform and flex beams, after which the flex beams are bent to the desired angle.

Abstract: A beam damper for damping acoustic noise generated by an actuator of a disc drive. The beam damper is compressed between a portion of a housing of the disc drive and an actuator motor. The beam damper includes a substantially flat platform affixed to a selected one of the housing and an upper or lower pole of the actuator motor. A plurality of flex beams extend from the platform at a selected angle and contact the remaining one of the housing and the upper or lower pole to resiliently bias the housing with respect to the actuator motor. The beam damper is preferably formed from a sheet of ductile metal which is stamped to form the platform and flex beams, after which the flex beams are bent to the desired angle.

Abstract: A hard disk drive having a plurality of disks mounted on the rotor of a current limited, electronically commutated dc motor. Windings on the stator of the motor are divided into serially connected run and start sections and first and seconds drive circuits are provided to operate the motor by alternatively enabling the first drive circuit to pass currents serially through the two sections of the winding and enabling the second drive circuit to pass currents through only the run sections of the windings. During spin up of the disk drive to operating speed, the first drive circuit is enabled and the second drive circuit is disabled to drive the disks to the speed at which the back emf limits on the acceleration of the motor using both sections of the windings reduces the acceleration to the maximum acceleration achievable at the current limit using the run sections alone. Spin up is then completed by enabling the second drive circuit and disabling the first drive circuit.