Abstract: A magnetic recording system utilizing a plurality of surfaces on a magnetic recording disk with recording zone boundaries established on the respective surfaces of the disk based on the performance characteristic of the read/write head associated with the surface. Since the zone boundaries are established uniquely for the performance of each head rather than by defining the boundaries of all zones for all surfaces in advance based on an assumed performance characteristic of the heads, the zone boundaries on one surface of the disk will not necessarily align with the zone boundaries on another surface of the disk. Similarly, when a plurality of disks are utilized, the zone boundaries will not necessarily be aligned. Improved utilization of the available stroke on the disk drive permits further improvement in recording density.

Abstract: Disclosed is a rigid disk drive information storage device which includes a rigid disk having an outside diameter in the range of about 33-34 mm., with a housing having a footprint that includes a width of about 35 mm. and utilizing a rotary actuator for positioning read/write recording elements across the surface of the disk. The disk storage devices further includes a footprint with length of about 50.8 mm., and includes in one embodiment dynamic head loading apparatus for loading the read/write recording elements into operative relationship with the disk. In another embodiment the rigid disk drive utilizes contact start stop loading and unloading of the read/write recording elements. An inertial latch is also provided for preventing rotation of the actuator when the drive is subjected to a rotational force.

Abstract: A disk drive is disclosed including a substantially monolithic stator. The stator is formed by a metal injected molding (MIM) process in which high silicon iron is sintered to produce a stator made from loss magnetic material. The low loss magnetic material is a low hysteresis loss, high resistivity material. A substantially monolithic stator without multiple laminations is thus achieved. Avoiding stator laminations in this manner permits the fabrication of a disk drive having a significantly reduced vertical profile while still suppressing undesired eddy current and hysteresis losses in the stator. The stator is advantageously directly machined with a central bore to receive a bearing assembly for the spindle of the hub of the drive motor. The disclosed stator geometry is optimized in three dimensions to minimize stator volume and maximize the stator winding volume.

Abstract: A disk drive apparatus including a drive motor with disks separated by annular spacers disposed around a spindle. The disks are held in place by an annular hub which is held in place by a shaped disk clamp that is shaped to apply substantially equal forces to equally spaced locations around the annular hub. The disk clamp is fastened to the spindle and T-shaped load tabs that apply force to the annular hub. The annular hub has a conical surface and the conical angle is greater than the angle the T-shaped load tabs assume when deflected when fastened to the spindle.

Abstract: A disk drive apparatus, by using an integrated base structure made up of a base portion and a printed circuit board, and an integrated cover structure made up of a cover casting and a printed circuit board, is able to achieve an overall thickness of 5 millimeters, so that such disk drive apparatus can meet the current PCMCIA card standard for Type II cards.

Abstract: The prerecorded embedded servo field includes at least one sub-field of prerecorded information that simultaneously provides (i) data for a first servo function and (ii) data for at least one other servo function. In another embodiment, a prerecorded embedded servo field includes a first sub-field of prerecorded information that simultaneously provides (i) automatic gain control data for a third sub-field and (ii) data for a first servo function, and a second sub-field of prerecorded information that simultaneously provides (i) automatic gain control (AGC) data for the third sub-field and (ii) data for a second servo function. Since the first and the second sub-fields in the servo field of this invention are used for AGC and another servo function, the sub-fields are arranged within the servo field so that the sub-field that requires the least precise AGC control is first and the sub-field that requires the most precise AGC control is last.

Abstract: Disclosed is a rigid disk drive information storage device which includes a rigid disk having an outside diameter in the range of about 33-34 mm., with a housing having a footprint that includes a width of about 35 mm. and utilizing a rotary actuator for positioning read/write recording elements across the surface of the disk. The disk storage devices further includes a footprint with length of about 50.8 mm., and includes in one embodiment dynamic head loading apparatus for loading the read/write recording elements into operative relationship with the disk. In another embodiment the rigid disk drive utilizes contact start stop loading and unloading of the read/write recording elements. An inertial latch is also provided for preventing rotation of the actuator when the drive is subjected to a rotational force.

Abstract: A connector assembly including a connector mounted to a printed wiring board and attached to a head disk assembly for strain relief is provided. The connector includes a plurality of through hole pins or surface mounted pins soldered to the printed wiring board. In one embodiment the connector also includes a connector hole that is formed in and extends through the connector. In one embodiment the connector assembly also includes a plurality of screws which pass through the printed wiring board, the connector, and threaded holes of the head disk assembly.

Abstract: An assembly for mounting a disk in a disk drive and including the disk mounting assembly. The disk mounting assembly includes a hub having a plurality of spoke recesses situated in the upper surface of the hub. The hub includes a protruding ledge for supporting a disk. A disk clamping ring adapted to fit about the hub is utilized. The disk mounting assembly also includes a spring washer having a circumferential edge surface adapted to contact the ring, the spring washer including a plurality of spokes extending inwardly from the circumferential edge surface of the washer to the center of the washer. A retainer is used to hold the center of the spring washer to the hub to squeeze a disk between the protruding ledge of the hub and the ring. The spokes of the spring washer are situated within respective spoke recesses of the hub to provide a low profile disk drive with more vertical room available for stator windings.

Abstract: A removable disk drive is combined with a protective device for use in a computer. The protective device is constructed as a jacket made of resilient material, the jacket enclosing at least a portion of the surface of the disk drive. In one embodiment, the disk drive includes a substantially rigid disk in a housing having a footprint that includes a first dimension of about 35 mm. In another embodiment, the removable disk drive includes a housing and a substantially rigid disk having a diameter in the range of from about 33 mm to about 34 mm.

Abstract: Disclosed is a rigid disk drive information storage device which includes a rigid disk having a diameter in the range of about 45-50 mm., with a housing having a footprint that includes a width of about 51 mm. and utilizing a rotary actuator for positioning read/write recording elements across the surface of the disk. The disk storage devices further includes a footprint with a length of about 70 mm., includes dynamic loading apparatus for loading the read/write recording elements into operative relationship with the disk and further includes an inertial latch for preventing rotation of the actuator when the drive is subjected to a rotational force.

Abstract: A magnetic recording system utilizing a plurality of surfaces on a magnetic recording disk with recording zone boundaries established on the respective surfaces of the disk based on the performance characteristic of the read/write head associated with the surface. Since the zone boundaries are established uniquely for the performance of each head rather than by defining the boundaries of all zones for all surfaces in advance based on an assumed performance characteristic of the heads, the zone boundaries on one surface of the disk will not necessarily align with the zone boundaries on another surface of the disk. Similarly, when a plurality of disks are utilized, the zone boundaries will not necessarily be aligned. Improved utilization of the available stroke on the disk drive permits further improvement in recording density.

Abstract: A disk drive information storage device having a pair of disks for storing information, the storage device including a clamp for mounting disks on a hub, the clamp including an annular element having a first set of fingers extending from the annular element in the first direction parallel to the central axis of the annular element, the first set of fingers providing a radial force on the inside edge of one of the disks, and the clamp including a second set of fingers extending from the annular element in a second direction parallel to the central axis of the annular element and opposite to the first direction, the fingers of the second set being for imposing a radially force on an inside edge of a second disk. In another embodiment, a disk drive information storage device with a pair of disks includes a spindle motor having a rotor which includes a disk-shaped portion having an outer diameter, and an upper surface for supporting one of the pair of disks.

Abstract: A novel method is used to remap tracks on a disk that contain a defect in a servo field so that a large seek discontinuity is not encountered. The method is applicable to both Class 2 and Class 3 defects. When a track with a Class 2 defect or adjacent tracks with a Class 3 defect are encountered, the tracks are skipped over in assigning physical track numbers to absolute track numbers. When a first defective track is encountered, the next track without a defect is assigned the physical track number that would have been assigned to the first defective track. As the remapping operation continues, each subsequent track with a Class 2 defect or adjacent tracks with a Class 3 defect is handled in a similar manner. The remapping operation is terminated when the number of mapped tracks is equal to the desired number of physical tracks n.

Abstract: Disclosed is a rigid disk drive information storage device which includes a rigid disk having an outside diameter in the range of about 33-34 mm., with a housing having a footprint that includes a width of about 35 mm. and utilizing a rotary actuator for positioning read/write recording elements across the surface of the disk. The disk storage devices further includes a footprint with length of about 50.8 mm., and includes in one embodiment dynamic head loading apparatus for loading the read/write recording elements into operative relationship with the disk. In another embodiment the rigid disk drive utilizes contact start stop loading and unloading of the read/write recording elements. An inertial latch is also provided for preventing rotation of the actuator when the drive is subjected to a rotational force.

Abstract: A method for optimizing the storage capacity of miniature disk drives without affecting reliability or yields of the disk drives uses an iterative seek process to define track zero. Initially, a physical reference point is defined and a transducer is moved in coarse steps from the physical reference point until interference with a stationery loading ramp or other mechanical component, hereinafter, "ramp," is detected. Upon detection of interference, the transducer is moved one coarse step away from the ramp and then the transducer is moved in fine steps towards the ramp until interference is again detected. Upon detection of interference, the transducer is moved away from the ramp a predetermined distance. After the transducer is moved the predetermined distance, a check is made for interference. If interference is detected, the transducer is moved in fine step towards the center of the disk until interference is no longer detected.

Abstract: An embedded servo system for a disk drive is disclosed. An asymmetrical position sub-field reduces the overhead of the disk position system. The sub-field includes at least two normal frame pairs and only one quadrature frame pair interleaved with one of the normal pairs to form the asymmetrical position sub-field. The prerecorded embedded servo information in each track of the disk includes a multiplicity of different length servo fields, i.e, each track includes at least two types of servo fields where the first type has a first length and the second type has a second length that is different from the first length. The length of a servo field refers to the number of prerecorded bytes in the servo field. The multiplicity of different length servo fields includes a first type having a full track address sub-field and a second type having a modulo track address sub-field in place of the full track address sub-field.

Abstract: Disclosed is a disk drive information storage device having a housing and a disk means for recording and reproducing information. The disk drive information storage device utilizes an actuator comprising a body portion supported by the housing for rotation about an axis, and a load beam connected to the body portion for rotation of a first end of the load beam in a plane substantially parallel to a surface of the disk means. The load beam includes an elongated lift tab having a free end which extends beyond the first end of the load beam, with the lift tab extending along an axis which is skewed from the centerline of the load beam. A slider body including a transducer for recording and reproducing information from the disk is supported by the load beam at a position intermediate the first end of the load beam and the axis of rotation of the body portion.

Abstract: Disclosed is a disk drive information storage device having a housing and a disk means for recording and reproducing information. The disk drive information storage device utilizes a rotary actuator which includes a load beam and structure for dynamically loading a transducer into operative relationship with a surface of the disk means. The transducer is supported adjacent to one end of the load beam. The load beam includes at its outermost end a lift tab which extends from the load beam along an axis which is skewed from the centerline of the load beam, with the lift tab including a curvilinear portion. A cam assembly is provided on the housing adjacent to the edge of the disk means, the cam assembly including a cam surface positioned in operative relationship with the lift tab. In one embodiment, the housing has a first external dimension of about 51 mm. In another embodiment, the disk means has a diameter in the range of from about 45 mm to about 50 mm.

Abstract: A spin motor control system includes a BEMF commutation circuit, a startup circuit and a monitor circuit, each of which operate utilizing digital techniques. The BEMF commutation circuit includes first and second counters that are programmable to accommodate for changing system parameters. The BEMF commutation circuit does not require the incorporation of an external capacitor, is insensitive to leakage current, and provides stable timing characteristics. The startup circuit also includes a counter and is programmable to accommodate for changing system parameters. The startup circuit does not require an external capacitor and provides stable generation of the startup pulses. The monitor circuit includes first and second counters for blanking the BEMF circuitry after commutation. The monitor circuit further includes circuitry for detecting and correcting the direction of rotation of the spin motor.