Quantum Corporation

Teac Corporation

Qume Corporation

Dzu Corporation

Pont Peripherals Corporation

William N Thanos

James D Fahey

Thomas R Stone

William G Moon

Bruce R Peterson

Steven L Kaczeus, Sr

Joshua Lindsay

David B Jeppson

Bryan John Mee

Tom L Lee

Misha I Rozenberg

Norman H Wulferdinger

Joseph C Liu

Kenneth W Cocksedge

Steven Louis Kaczeus

A disk drive system provides a low height device by mounting a circuit board or boards containing the electronic circuitry in the same enclosure with the head-disk assembly (HDA). The drive actuator mechanism is positioned at one side of one end of the enclosure and the circuit board or boards are positioned at the other side of that end of the enclosure. A gasket seals the HDA from contaminants, while the enclosure protects the electronic circuitry and cables from physical damage, electrostatic charges and electromagnetic interference. The circuit board or boards can be removed from the enclosure without removing the entire disk drive from the using system, and the entire drive assembly can readily be removed from the using system for replacement or use in another system.

High capacity, low profile disk drive system

A low profile disk drive assembly comprises an enclosure having a sealed volume substantially laterally displaced with respect to a circuit volume. The sealed volume has an extension which extends laterally toward one corner portion of the enclosure whereas the circuit volume is disposed substantially within an adjacent corner portion of the enclosure. The sealed volume contains one or more disks and a read/write head actuator assembly. A flexible circuit, which couples to the read/write head actuator assembly inside the sealed volume, extends from inside sealed volume, through a wall of the enclosure which separates the sealed volume from the circuit volume, across the circuit volume, and to an interface connector. The interface connector may be used to connect the disk drive assembly to a system with which the disk drive assembly is to operate. A multichip module is mounted on one side of the flexible circuit inside the circuit volume. Preamplification circuitry is mounted on one side of the flexible circuit inside the sealed volume. The flexible circuit, the multichip module, and the preamplification circuit may comprise a separately testable subassembly. In some embodiments, a portion of the enclosure is removable to allow access to the circuitry, such as the multichip module, mounted on the flexible circuit in the circuit volume.

Low profile disk drive assembly

A method is provided for allocating digital processing activities of an embedded microcontroller within a disk drive between repetitive periodic digital servo loop service routines synchronized to rotation of a data storage disk of the drive and irregularly occurring host service routines supporting a high level, digital interface to a host computing environment. The new method comprises the steps of:

Servo pause for disk drive embedded multi-tasked controller

A disk drive includes at least one reference track having a plurality of sectors which are read and averaged in order to compensate for spindle offset. The disk drive has a head position servo system controls a head position actuator and includes a polyphase optical encoder which is initially calibrated by reference to dark current values and recalibrated periodically by reference to the reference track. Preferably, at least two reference tracks are located at the extremes of the radial displacement of the actuator so that variations in gap dimension between a scale mounted to the actuator and a fixed reticle-mask over a photodetector array of the encoder may be measured and compensated for. The method for initializing the drive and for periodically updating its calibration of the encoder and the head position servo is also described.

Head position recalibration for disk drive

A micro-Winchester disk drive subsystem includes a data block sequencer, cache memory and interface for a host computing machine. The drive includes a base and a plurality of non-removable directly rotated disks forming data storage surfaces. A balanced rotary head transducer actuator is mounted to the base for a plurality of data transducer heads among a multiplicity of concentric data tracks formed on each data storage surface of each of the disks. The track following servo system includes a position encoder coupled between the actuator structure and the base, prerecorded data track centerline information at a radially outermost region and at a radially innermost region of each data surface, and a temperature sensor for sensing temperature of the base at the vicinity of the position encoder. An actuator driver circuit is connected to supply electrical driving current to the actuator structure; and, a single, time divided multi-tasked digital including an analog to digital converter is connected to receive the position information from the position encoder, centerline information from the disk surfaces read by the data transducer and temperature sensed by the temperature sensor during a calibration operation in one phase of its operational cycle, the other phase being devoted to supervision data block handling functions of disk drive data block sequencer cache memory and interface. During track following operations, centerline information is derived from information obtained in the calibrate operation. The temperature sensor is periodically checked and recalibration is carried out when drive temperature changes.

Head position control system for fixed drive including position encoder,

A micro-Winchester disk drive subsystem includes a data block sequencer, cache memory and interface for a host computing machine. The drive includes a base and a plurality of non-removable directly rotated disks forming data storage surfaces. A balanced rotary head transducer actuator is mounted to the base for a plurality of data transducer heads among a multiplicity of concentric data tracks formed on each data storage surface of each of the disks. The track following servo system includes a position encoder coupled between the actuator structure and the base, prerecorded data track centerline information at a radially outermost region and at a radially innermost region of each data surface, and a temperature sensor for sensing temperature of the base at the vicinity of the position encoder. An actuator driver circuit is connected to supply electrical driving current to the actuator structure; and, a single, time divided multi-tasked digital including an analog to digital converter is connected to receive the position information from the position encoder, centerline information from the disk surfaces read by the data transducer and temperature sensed by the temperature sensor during a calibration operation in one phase of its operational cycle, and other phase being devoted to supervision data block handling functions of disk drive data block sequencer cache memory and interface. During track following operations, centerline information is derived from information obtained in the calibrate operation. The temperature sensor is periodically checked and recalibration is carried out when drive temperature changes.

High performance, high capacity micro-winchester disk drive

An analog servo system suitable for accurately controlling the carriage speed of a high speed printer over a relatively wide range. The system includes an analog tachometer with circuit means which enables the tachometer to operate in either a high gain mode (used at normal or lower carriage speeds) or a low gain mode (used at higher carriage speeds). The tachometer gain mode (or 'electronic gear') is controlled by an external command signal such as a single bit supplied by the control microprocessor of the printer. The state of the command signal controls a time constant in the tachometer circuit means which determines the gain mode.

Multi-speed analog servo

A nominal carriage velocity profile is initiated during each carriage positioning interval which enables the carriage to be decelerated and stopped at the proper position for printing. However, the carriage velocity profile can be modified during the positioning interval to avoid decelerating if printing can occur on the fly; i.e., if the print element (and ribbon) are able to complete any necessary positioning by the time the carriage arrives at its printing position. In accordance with the preferred embodiment, the slave microprocessor produces a READY signal in advance of the print wheel arriving at its destination orientation. The READY signal indicates that both the print wheel and ribbon will reach their destinations and be ready for printing within a fixed time interval; e.g., three milliseconds. In response to the READY signal, the master microprocessor inhibits further adjustments in the carriage speed and permits the carriage to assume a 'fly' mode. Additionally, from known carriage position and velocity information, the master microprocessor determines the time at which the carriage will pass through the printing position and when the hammer is to be fired.

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San Jose, CA, United States of America

William N Thanos