Abstract: The present invention provides an improved magnetic data storage and retrieval system, which can absorb external shock and is easily attached to a host system. By setting bumpers in the four corners of a magnetic data storage and retrieval system, external shock can be absorbed to prevent a magnetic disk from being displaced from the proper alignment with its spindle motor. With this arrangement, in the two corners on the end portion side of a guide groove formed in the base, pedestal surfaces are formed in one side of the guide groove, and plate-like bumpers and are set on the pedestals. Further, in the remaining two corners, insertion-type bumpers may be set and a label covering part of them may be affixed.

Abstract: An arrangement structure of the printed circuit board and the interface cable connector of a magnetic disk drive for increasing the degree of freedom of the arrangement of a spindle motor, and for minimizing the size of a printed circuit board. An interface cable connector is disposed on the side opposite to the spindle motor, and the printed circuit board is sized so as not to contact with the spindle motor in the height direction. This allows the degree of freedom of the arrangement of the spindle motor to increase. Further, the distance between the interface cable connector and the preamplifier connector on the printed circuit board is short. Thus, the size of the printed circuit board can be made as small as possible.

Abstract: A magnetic circuit is provided in an enclosure that can efficiently generate magnetic flux from the enclosure, configuring a magnetic disk, to a magnetic disk. Thus, by providing such a magnetic circuit, a magnetic field different from that in other enclosure parts, that is, a local magnetic field, is generated from the magnetic circuit in case the disk device is set in an external magnetic field. Hence, this local magnetic field can effectively erase data in the magnetic disk. In particular, since the local magnetic field is generated even if the external magnetic field is weak, it is possible to not only suppress the demagnetization of permanent magnets used in the spindle motor at minimum, but also effectively erase data in the magnetic disk.

Abstract: An attachment structure and method for a disk drive apparatus for making the coupling resonance frequency of a hard disk drive the same whether one disk is loaded or a plurality of disks are loaded based upon parameters obtained from a simulation model. The modeling of a coupling vibration for one disk and for two disks is performed using a coupling vibration model of a linear two degree-of-freedom system. The component parts of a spindle motor providing a spring constant Kp are adjusted so that the resonance frequency determined by coupling that of a spindle motor with that of the disk(s) is made much the same whether one disk or two disks are loaded. This adjustment enables stable track following to be secured without the need for adding dummy disks and other parts.

Abstract: A spindle motor employed for a hard disk unit, including a hub having an outer peripheral wall portion provided with a rotor magnet on its outer peripheral surface and formed so as to be able to support the inner peripheral portion of a hard disk and a stator coil fixed so as to be positioned outwards in the radial direction of the disk and face the rotor magnet. This spindle motor is assembled in the disk unit, in which each stator coil is disposed so that the tracing of the magnetic head in movement is positioned between adjacent cores, thereby the magnetic head is affected less by the leak magnetic flux from the stator coil. In addition, the scanning head is moved to its unloading position with use of an energy accumulated in the capacitor when the power of the disk unit is turned off.

Abstract: To provide a magnetic disk apparatus in which an outline of a seal for hermetically sealing is identical with that of a cover and base having steps at the periphery thereof. In a sealed magnetic disk apparatus in which a cover and base having steps at the periphery thereof are joined together via a seal, two slopes 48 and 50 are provided, in a turned or stairs-like form, at each step portion at the periphery of a cover 60 and a base 40. The first slope 48 descends from the periphery toward the inside, and the second slope 50 connecting to the first slope descends from the inside toward the periphery. The slopes of the cover are provided to mate with those of the base, respectively. A seal 70 has an outline which is substantially identical with that of the cover 60 and the base 40 and includes projections 72 and 74 covering the slopes.

Abstract: A ferromagnetic body is attached or embodied within the actuator arm in a disk drive. The ferromagnetic body is positioned so that the magnets of the voice coil motor attract the ferromagnetic body and produce a force to move the actuator arm so the read/write head attached thereto lands in the landing region of the disk in the event of a power interruption.