Abstract: A magnetic disc unit includes a rotating disc type magnetic disc, a head for recording and reproducing data to and from the magnetic disc, and a head support mechanism for supporting the head. The magnetic disc unit includes a shroud surrounding an outer periphery of the magnetic disc other than at least at an inserting part of a carriage arm which is linked to the magnetic head support mechanism. A gap between an end face of the outer periphery of the magnetic disc and the shroud is set in a range not less than 0.1 mm but not greater than 0.4 mm.

Abstract: A magnetic disk drive is to be provided wherein oscillations in thrust, conical and translational modes of a spindle caused by disturbance are to be damped to diminish a positioning error and thereby attain a high recording density and improved accessing performance. In one embodiment, there is provided a compensation circuit using acceleration or angular acceleration sensors, the sensors being disposed on a base, a cover or a PCB (printed circuit board) of a magnetic disk drive so that they can detect disturbance effectively, and wherein a mechanical system transfer characteristic of and other parameters in thrust, conical, or translational mode of a spindle are acquired or calculated by a processor and unnecessary oscillation in each mode is compensated. In another embodiment, to measure a transfer characteristic of the spindle in thrust mode and other parameters after installation of the magnetic disk drive in a case, piezoelectric elements are provided as one of oscillating means.

Abstract: The positioning accuracy of a magnetic head decreases due to vibrations in the in-plane rotation mode of an HDD, which are caused by couple or disturbance occurring in seek operation, due to vibrations in the thrust mode, and the conical mode, of the spindle, which are caused by disturbance, and due to vibrations in the case thrust mode, the spindle fall mode, and the like. In one embodiment, an elastic support member includes a pillar-shaped part. The elastic support member is provided with a recess on a surface opposite to a corner of a base, and longitudinal fin projections on the upper and lower sides with respect to the recess. The base is provided at its corner with a horizontal fin that is parallel to a disk surface. The horizontal fin is inserted into the recess of the elastic support member. The longitudinal fin projections come into contact with the base, and control basic vibrational characteristics on both the upper and lower sides with respect to the horizontal fin.

Abstract: A magnetic disc unit includes a rotating disc type magnetic disc, a head for recording and reproducing data to and from the magnetic disc, and a head support mechanism for supporting the head. The magnetic disc unit includes a shroud surrounding an outer periphery of the magnetic disc other than at least at an inserting part of a carriage arm which is linked to the magnetic head support mechanism. A gap between an end face of the outer periphery of the magnetic disc and the shroud is set in a range not less than 0.1 mm but not greater than 0.4 mm.

Abstract: A magnetic disc unit includes a rotating disc type magnetic disc having an outer periphery, and a carriage arm linked to a head support mechanism for a recording/reproducing head. A base has an outer periphery and mounts the rotating disc type magnetic disc and the carriage arm, and has a side wall with an inner wall surface having an opening for inserting the carriage arm. The inner wall surface of the side wall defines a shroud surrounding the outer periphery of the magnetic disc, except at the opening in the side wall where the shroud is projected inwardly so as to decrease an opening angle of the opening in the side wall. A gap between the outer periphery of the magnetic disc and the shroud is set in a range not less than 0.1 mm but not greater than 0.6 mm.

Abstract: A magnetic disk apparatus includes a plurality of magnetic disks driven to rotate by a spindle motor, arms supporting magnetic heads on the magnetic disks, an actuator for moving the arms on the magnetic disks by a voice coil motor, and a housing which surrounds the magnetic disks, the arms and the actuator. A shroud which arcuately surrounds the magnetic disks along the outer periphery thereof has an opened portion for inserting the arms is formed in a part of the housing. The shroud on an upstream side of the arms relative to airflow generated by the magnetic disks when rotating is provided with an opening having a greater width than that of a gap defined between the shroud and the outer periphery of the magnetic disks. An empty bypass channel is provided which communicates from the opening through a rear side of the voice coil motor to the downstream side of the arms.

Abstract: A magnetic disc unit includes a rotating disc type magnetic disc having an outer periphery, and a carriage arm linked to a head support mechanism for a recording/reproducing head. A base has an outer periphery and mounts the rotating disc type magnetic disc and the carriage arm, and has a side wall with an inner wall surface having an opening for inserting the carriage arm. The inner wall surface of the side wall defines a shroud surrounding the outer periphery of the magnetic disc, except at the opening in the side wall where the shroud is projected inwardly so as to decrease an opening angle of the opening in the side wall. A gap between the outer periphery of the magnetic disc and the shroud is set in a range not less than 0.1 mm but not greater than 0.6 mm.

Abstract: The positioning accuracy of a magnetic head decreases due to vibrations in the in-plane rotation mode of an HDD, which are caused by couple or disturbance occurring in seek operation, due to vibrations in the thrust mode, and the conical mode, of the spindle, which are caused by disturbance, and due to vibrations in the case thrust mode, the spindle fall mode, and the like. In one embodiment, an elastic support member includes a pillar-shaped part. The elastic support member is provided with a recess on a surface opposite to a corner of a base, and longitudinal fin projections on the upper and lower sides with respect to the recess. The base is provided at its corner with a horizontal fin that is parallel to a disk surface. The horizontal fin is inserted into the recess of the elastic support member. The longitudinal fin projections come into contact with the base, and control basic vibrational characteristics on both the upper and lower sides with respect to the horizontal fin.

Abstract: A magnetic disc unit having a rotating disc type magnetic disc, a head for recording and reproducing data to and from the magnetic disc, and a shroud surrounding an end surface of an outer periphery of the magnetic disc, except a part where a carriage arm is inserted, wherein a gap between the outer peripheral end surface of the magnetic disc and the shroud is set in a range which is greater than 0.1 mm but not greater than 0.6 mm.

Abstract: A magnetic disk drive having a high recording density and enabling high speed transfer is achieved by reducing vibration of a carriage arm assembly to reduce a positioning error. The disk drive is configured so that a carriage arm is configured by two arm portions, the arm portions being coupled to each other by a restraint member through a viscoelastic material, the restraint member being supported on a carriage body or an area of the carriage arm in the vicinity of the body by means of adhesion or a viscoelastic material. By providing a high damping effect against various vibration modes in which in-plane bending and out-plane bending of the carriage arm are generated, vibration of the carriage arm assembly is suppressed, so that the positioning error is reduced, thereby the magnetic disk drive having a high recording density can be achieved.

Abstract: A magnetic disk drive is to be provided wherein oscillations in thrust, conical and translational modes of a spindle caused by disturbance are to be damped to diminish a positioning error and thereby attain a high recording density and improved accessing performance. In one embodiment, there is provided a compensation circuit using acceleration or angular acceleration sensors, the sensors being disposed on a base, a cover or a PCB (printed circuit board) of a magnetic disk drive so that they can detect disturbance effectively, and wherein a mechanical system transfer characteristic of and other parameters in thrust, conical, or translational mode of a spindle are acquired or calculated by a processor and unnecessary oscillation in each mode is compensated. In another embodiment, to measure a transfer characteristic of the spindle in thrust mode and other parameters after installation of the magnetic disk drive in a case, piezoelectric elements are provided as one of oscillating means.

Abstract: A magnetic disk apparatus includes a plurality of magnetic disks driven to rotate by a spindle motor, arms supporting magnetic heads on the magnetic disks, an actuator for moving the arms on the magnetic disks by a voice coil motor, and a housing which surrounds the magnetic disks, the arms and the actuator. A shroud which arcuately surrounds the magnetic disks along the outer periphery thereof has an opened portion for inserting the arms is formed in a part of the housing. The shroud on an upstream side of the arms relative to airflow generated by the magnetic disks when rotating is provided with an opening having a greater width than that of a gap defined between the shroud and the outer periphery of the magnetic disks. An empty bypass channel is provided which communicates from the opening through a rear side of the voice coil motor to the downstream side of the arms.

Abstract: Due to the raised operating rotation speed, it has become an important technical theme to reduce fluid vibrations caused by high speed air flows passing the wiring extension in a head gimbal assembly in order to raise the positioning accuracy for higher density recording. Embodiments of the present invention provide a spring structure to the wiring extension. In a wiring extension holding section formed on the carriage side, the wiring extension is retained at the center of the groove of the holding section by the repulsive force of spring members. By preventing the wiring extension from being directly subject to high speed air flows generated by a high-speed rotating disk, this structure is intended to suppress vibrations of the wiring extension caused by high-speed air flows passing the wiring extension.

Abstract: A magnetic disk device having a magnetic disk for recording information, a spindle motor for driving the magnetic disk for rotation, a magnetic head for reading information from the magnetic disk, a carriage arm for supporting the magnetic disk, a voice coil motor for moving the carriage arm, a loading/unloading mechanism for retracting the carriage arm from a position on the magnetic disk, and a shroud for forming a peripheral wall. The magnetic device includes an air passage positioned between the loading/unloading mechanism and the shroud.

Abstract: A magnetic disk apparatus includes magnetic disks stacked on a rotating shaft, arms supporting magnetic heads, a rotary actuator for moving the arms, and a housing forming at least a part of an arcuate-shaped shroud which substantially surrounds a portion of side surfaces of the magnetic disks so as to define a gap between the shroud and the portion of the side surfaces of the magnetic disks. The arcuate-shaped shroud has portions delimiting an open space adjacent to another portion of the side surfaces of the magnetic disks which is located on a downstream side of the arms relative to an air flow which moves on surfaces of the magnetic disks. A bypass channel provides air flow to the disks in a region of the open space at a reduced pressure on the downstream side of the arms with respect to pressure at an upstream side of the arms.

Abstract: A magnetic disk device having a magnetic disk for recording information, a spindle motor for driving the magnetic disk for rotation, a magnetic head for reading information from the magnetic disk, a carriage arm for supporting the magnetic disk, a voice coil motor for moving the carriage arm, a loading/unloading mechanism for retracting the carriage arm from a position on the magnetic disk, and a shroud for forming a peripheral wall. The magnetic device includes an air passage positioned between the loading/unloading mechanism and the shroud.

Abstract: A magnetic disc unit which can restrain occurrence of flutter so as to countermeasure such a problem that the larger the rotational speed of discs, the higher the flutter, causing heat positioning errors, in order that the high rotational speed and high positioning accuracy are consistent with each other. Discs are surrounded along their outer peripheries by a shroud (outer wall) while a gap between end faces of the discs and the shroud is decreased to a predetermined distance, thereby to eliminate air pressure differential between opposite surfaces of each of the discs in order to reduce flutter.

Abstract: A magnetic disc unit having a rotating disc type magnetic disc, a head for recording and reproducing data to and from the magnetic disc, and a shroud surrounding an end surface of an outer periphery of the magnetic disc, except a part where a carriage arm is inserted, wherein a gap between the outer peripheral end surface of the magnetic disc and the shroud is set in a range which is greater than 0.1 mm but not greater than 0.6 mm.

Abstract: In a magnetic disc apparatus including a plurality of magnetic discs mounted on a spindle, arms supporting magnetic heads, a rotary actuator for the arms, and a housing having an arcuate-shaped shroud, the improvement wherein gaps between the shroud and the sides of outer peripheries of the magnetic discs are larger than 0.1 mm and less than 0.6 mm. An open space is located, downstream of the arms with respect to the air flow on surfaces of the magnetic discs, the open space being devoid of the shroud. An opening is provided in the shroud, upstream of the arms with respect to the air flow and having a greater width than a width of the gaps defined between the magnetic discs and the shroud, and a bypass channel is provided which communicates between the opening and open space.

Abstract: A magnetic disk drive having a high recording density and enabling high speed transfer is achieved by reducing vibration of a carriage arm assembly to reduce a positioning error. The disk drive is configured so that a carriage arm is configured by two arm portions, the arm portions being coupled to each other by a restraint member through a viscoelastic material, the restraint member being supported on a carriage body or an area of the carriage arm in the vicinity of the body by means of adhesion or a viscoelastic material. By providing a high damping effect against various vibration modes in which in-plane bending and out-plane bending of the carriage arm are generated, vibration of the carriage arm assembly is suppressed, so that the positioning error is reduced, thereby the magnetic disk drive having a high recording density can be achieved.