1153results about "Track finding/aligning" patented technology

A read / write head includes a slider provided with an electromagnetic transducer element (or an optical module), an actuator, and a suspension. The actuator includes a fixed part, a movable part, and at least two beam members for coupling them together. The beam members have a displacement generating means that elongates and contracts by inverse piezoelectric effect or electrostrictive effect. The fixed part is fixed to the suspension, and the movable part is fixed to the slider. Upon the elongation and contraction of the displacement generator, the displacement generator deflects and the movable part displaces linearly, circularly or rotationally with respect to the fixed part, and the electromagnetic transducer element displaces in a linear or circular orbit, so that the electromagnetic transducer element intersects recording tracks. In the actuator, the fixed part, movable part and beam members are formed as an integrated single piece by providing a hole and / or a cutout in a sheet-like member constructed of a piezoelectric or electrostrictive material. The actuator of the structure illustrated is used for the positioning of a direction intersecting recording tracks. In this case, the total sum of voltages applied on the displacement generating means is controlled in such a manner that it is constant at any time, thereby controlling position fluctuations of the electromagnetic transducer element in the direction vertical to the recording medium surface.

A digital servo control system for disk drives is an "embedded" system-one in which servo control information is embedded on the same disk surface as the user data. In contrast to known embedded-servo systems in which a space-consuming series of many dibit pairs is present, the present system provides only a single dibit pair in a fractional positional error (PESF) area. Thus, the disk drive's read head encounters only a single dibit pair per sample period (or per data sector), thus saving valuable disk space that may be used for user data. Various pre-processing methods may be provided so as to pre-process the measurement derived from the single dibit pair per sample period (or data sector), so as to compensate for non-ideal characteristics of the dibit measurement. The system thus provides an accurate and robust servo control system, while sacrificing a minimum amount of valuable disk space to the servo information field.

The systems, methods and products of the invention include systems and methods for manufacturing servo tracks on a magnetic tape. In one aspect, the invention includes systems for manufacturing magnetic tapes having servo tracks thereon wherein the servo tracks are optically detectable and are capable of being processed by a servo control system for maintaining alignment of a magnetic recording head with the data tracks on the recording side of the magnetic tape. In one practice, the manufacturing systems described herein engrave the servo tracks onto the non-recording side of a magnetic tape by directing a laser beam at the non-recording side of the magnetic tape. In another practice, the manufacturing systems described herein engrave the servo tracks onto the magnetic side of a magnetic tape by directing a laser beam at the magnetic side of the magnetic tape. Such engraved patterns can act as optical servo tracks for maintaining alignment of the recording head with the data tracks on the magnetic tape.

A fine lateral head positioner for a tape drive includes a frame mounted to a base of a tape transport. A tape head slides laterally along a head guide. A guide beam actuated by a fine position actuator applies limited transverse adjustments to the tape head relative to a tape transport path via a cam and cam-follower arrangement. A coarse positioner between the frame and the base provides coarse position adjustment of the tape head laterally among multiple sets of parallel tracks defined along a longitudinal direction of a magnetic tape moving along the tape transport path, and the guide beam provides fine position adjustment of the tape head enabling it to follow in real time a particular set of parallel tracks of the tape during each data writing or reading operation.

Embedded servo sectors within a data track of a hard disk drive including a rotating data storage disk and a closed loop rotary actuator structure for positioning a data transducer head relative to the data track are written by a method including the steps of positioning the rotary actuator structure relative to the data track with a laser-interferometer-based servo writer and writing a pattern of circumferentially sequential, radially offset fine position bursts within each servo sector with the data transducer head, this step including writing-in undetermined position errors within each pattern being written, moving the disk drive to a self scan environment away from the servo writer, operating the rotary actuator structure in closed loop for following the data track by reference to the servo burst pattern, extracting the undetermined position error from each pattern thereby to iteratively determine written-in position errors, generating burst correction values from the determined written-in position errors, and writing the burst correction values to the data track for later use by the closed loop rotary actuator structure during following of the data track to remove the written-in position errors.

A detector detects, in read data, a servo address mark of a type indicated by a register. Every time a SAM is detected during a self servo process, a CPU carries out tracking control in accordance with corresponding servo data. The CPU causes a head to write a corresponding type of additional servo data item in a disk at a position offset from the position of servo data containing the detected SAM, by a predetermined distance in a circumferential direction of the disk. Every time sets of servo data, each consisting of various types of data items, are written in the disk, the head is moved by a predetermined pitch in a radial direction of the disk.

A head suspension for supporting a head slider over a disk in a dynamic storage device and providing precise movement of the head slider relative to tracks on the disk. The head suspension includes a load beam, a flexure having a slider mounting region, and a dimple interface transmitting a load beam force to the slider mounting region. The head suspension further includes a microactuator mounted to the load beam. Movement of the microactuator is transmitted through the dimple interface by action of frictional forces at the dimple interface so as to cause movement of the slider mounting region transverse to tracks on the disk. A method of precisely moving a head slider supported by a head suspension includes providing and driving a microactuator configured to transmit movement of the microactuator to a slider mounting region through a dimple interface by action of frictional forces at the dimple interface.

The present invention provides a magnetic head device exhibiting a good bonded state of a piezoelectric element and a load beam, and excellent reliability. The magnetic head device includes a slider provided with a reproducing element for detecting a magnetic signal recorded on a recording medium, and a recording element for recording a magnetic signal on the recording medium, an elastic supporting member for supporting the slider, and piezoelectric elements mounted on the elastic supporting member, for distorting the elastic supporting member to change the position of the slider. The piezoelectric element and the elastic supporting member are bonded together with a photo-curing and thermosetting epoxy adhesive resin having a Young's modulus of 1 GPa or more at 25° C., and a glass transition temperature of 90° C. or more.

A disc drive includes a transducer having a separate element for writing information and a separate element for reading information to and from the disc. In a disc drive designated to read and write long sequential records, the track misregistration budget is reduced to account for previously written tracks not being encroached on one side. An initial track is written. Subsequent tracks are written after a seek in one direction. The subsequent track is written so that the initially written track is overwritten to one side and leaves a track having a width substantially equal to the width of the read element. Records can be written into data bands of a selected number of tracks. A guard band is left between groups of data bands so that data on tracks in subsequent data bands are not overwritten.

The amount of position error written into a servo burst pattern can be reduced by using additional media revolutions to write the pattern. Where the edges of two servo bursts are used to define a position on the media, trimming the first burst and writing the second burst on separate revolutions will result in a different amount of position error being written into each burst. The end result will be a reduction in the overall error in position information. In order to further reduce the position error given by a burst pair, each burst also can be trimmed and / or written in multiple passes. This description is not intended to be a complete description of, or limit the scope of, the invention. Other features, aspects, and objects of the invention can be obtained from a review of the specification, the figures, and the claims.

An electrical connection structure connects a piezoelectric element to a flexure with a conductive adhesive. An electrode surface is formed on the piezoelectric element, and a terminal surface is formed on the wiring member and is smoother than the electrode surface. A the gold plate layer is formed on the terminal surface and is connected to the electrode surface with the conductive adhesive. At least one recess is formed by laser processing on the conductive terminal surface layer. The electrical connection structure substantially equalizes the surface roughness of the terminal surface with the gold plate layer to that of the electrode surface, improves a bonding strength on the terminal surface nearly to that on the electrode surface, enhances the reliability of electrical connection between the electrode surface and the terminal surface, maintains electrical characteristics of the terminal surface, and prevents contamination around the terminal surface.

A method and apparatus for actively controlling the gram load on a disk drive suspension assembly and to a disk drive using the present disk drive suspension assembly. The gram load can be actively changed by changing the applied voltage to one or more multi-layer piezoelectric actuators attached to the head suspension. The active gram control system allows the gram load to be changed on a non-permanent basis and to control the gram load to a much finer scale than can be accomplished using conventional techniques. By attaching the first and second ends of the piezoelectric actuator to discrete locations on the load beam, while the portion of the piezoelectric actuator between the first and second ends remains unattached to the load beam, a force non-parallel to the load beam can be applied to the head suspension.

Head position control is implemented in a disk drive for the case in which a disk is assembled into the disk drive after a precise track is recorded onto it using an external apparatus, which is capable of high-speed access even if there is eccentricity between a track defined by servo information and the center of rotation of the track. Two phase servo bursts consisting of servo information are recorded onto each of the servo information regions of a disk surface, in mutual alternation, the strength ratio between signals detected from these two phase servo bursts being used to determine to which side the head is displaced. By performing control so that this strength ratio is a prescribed value at each angular position, control is achieved so that the head moves along a circular path of rotation, even if there is eccentricity in the servo circular path defined by the recorded servo information with respect to the center of rotation.

A suspension for a disk drive includes a mount plate adapted to mount to a primary actuator, a functional end portion adapted to carry a slider, and a hinge disposed between the mount plate and the functional end portion. A mounting configuration is provided on the mount plate for mounting the suspension to the primary actuator. A pair of secondary actuators are mounted in longitudinally overlapping relationship with the mounting configuration so as to minimize the impact of the secondary actuators on suspension length. The secondary actuators are operatively connected to the hinge for producing sway displacement of the slider.

An electrode structure of a piezoelectric element is provided. The piezoelectric element 23a (23b) constitutes a piezoelectric actuator 19 attached to an attaching part 30 of an object, to minutely move a movable part 15 of the object relative to a base part 13 of the object according to deformation occurring on the piezoelectric element in response to a power applied state of the piezoelectric element. The electrode structure includes an electrode 41a formed on one of a pair of electrode forming faces 31a and 31b of the piezoelectric element on an inner side of a peripheral zone 31a1, the peripheral zone being defined along the periphery of the electrode forming face 31a on which the electrode is formed. The electrode structure also includes a non-electrode part 51 formed in the peripheral zone. Even if the peripheral zone 31a1 of the electrode forming face 31a having a short-circuit causing possibility touches the attaching part 30, no short circuit occurs.

The present invention relates to controlling an actuator for positioning a read / write head in storage devices such as disk drives. More specifically, the invention relates to using a sensor to detect the disk vibration amplitude perpendicular to the disk surface, and using feed forward control to cancel or counteract the tendency of the read / write head to deviate off-track due to disk vibration. Various approaches are proposed to detect the disk vertical vibration.

In one illustrative example, a method for use in reducing Repeatable Run Out (RRO) error in a data storage device involves obtaining an RRO measurement for each track of a limited number of N disk tracks; characterizing the RRO measurement for each track with real and imaginary values by performing a discrete Fourier transform (DFT) calculation on each RRO measurement; performing a least-squares fit on all of the real values to identify a first set of (n+1) coefficients of an nth-order polynomial function which is a function of disk track r and representable in the form Ai(r)=anrn+a(n−1)r(n−1)+ . . . +a1r+a0; and performing a least-squares fit on all of the imaginary values to identify a second set of (n+1) coefficients of an nth-order polynomial function which is a function of disk track r and representable in the form Bi(r)=bnrn+b(n−1)r(n−1)+ . . . +b1r+b0. RRO compensation is performed based on the relation DRRO(r, s)=Σi for all H {Ai(r)cos(i(s2π / total_sectors))+Bi(r)sin(i(s2π / total_sectors))} where DRRO is the estimated RRO error; r is a track number; s is a sector number at track number r; i is an RRO harmonic number; H is a set of harmonics to be compensated; and total_sectors is a total number of sectors along track number r. Advantageously, RRO variations across the disk can be accurately compensated for with use of a small amount of memory.

An audio signal encoding and decoding apparatus capable of transmitting an audio signal or an audio signal together with a sound-field-effect-processed audio signal are provided. The audio signal encoding apparatus includes a core encoder to encode an input audio signal according to an audio signal encoding standard, a core decoder to decode the encoded audio signal output from the core encoder, a sound-field-effect processor to perform a sound-field-effect process on the input audio signal, a selector to selectively output the input audio signal or the sound-field-effect-processed audio signal output from the sound-field-effect processor, a subtraction unit to calculate a difference signal between the signals output from the core decoder and the selector, an extension encoder to encode the difference signal output from the subtraction unit according to an arbitrary encoding scheme and to output the extension encoded signal, and a multiplexer to multiplex the encoded audio signal output from the core encoder and the extension encoded signal output from the extension encoder into a composite encoded signal and to output the composite encoded signal.

There is provided a magnetic disk drive in which a flying-height fluctuation produced by the operation of a fine actuator is decreased, the reliability is high, and recording density is high. For this purpose, the magnetic disk drive is configured as described below. The magnetic disk drive has a suspension including a base plate connected to a carriage, a load beam fitted with a slider, and a fine actuator which is provided on the base plate and finely moves the load beam. The configuration is such that the shortest track travel time using the fine actuator is larger than the inverse number of the local maximum of a flying-height fluctuation frequency of the suspension by the fine actuator. Also, the configuration is such that the shortest track travel time using the fine actuator is larger than the inverse number of the natural frequency of first torsion mode of the suspension by the fine actuator.

The Invention provides a motor drive semiconductor integrated circuit for driving and controlling a voice coil motor that can conduct a seek operation, a track follow operation and a settling operation through PWM control, has desired control accuracy and can be produced by a CMOS process. In a voice coil motor drive circuit (200) for executing positioning control of a magnetic head by feedback-controlling a driving current of a voice coil motor (108) for moving a magnetic head (106) over a magnetic disk for reading information from a storage track on the magnetic disk driven for rotation while a read state of the magnetic head is being monitored, head movement control such as a seek operation, a track follow operation etc, of the magnetic head is executed by PWM driving on the basis of a command value from a controller.

A disk device and a disk medium are disclosed in which a plurality of servo cylinders on the surface of at least one disk are divided into several areas, and a different servo signal frequency is set and recorded for each of the areas. The servo cylinders are divided into predetermined areas, and a different servo signal frequency for each of the areas is set so that the recording density of the servo signal recorded in the disk can be set so as to allow the servo signal demodulation characteristic to be included in a relatively superior range. In the disk device, the boundary between the area of a first servo signal frequency and the area of a second servo signal frequency adjoining the first servo signal frequency area is preferably formed with an area in which a servo signal pattern written with the first servo signal frequency and a servo signal pattern written with the second servo signal frequency are arranged on the same servo cylinders.

A precise positioning actuator for precisely positioning at least one head element is provided with a base and a pair of movable arms capable of displacing in response to a drive signal applied to the actuator. The pair of movable arms extend from the base for catching a head slider with at least one head element in a space between the pair of movable arms. Each of the pair of movable arms includes an arm member made of an elastic sintered ceramic and having substantially the same cross sectional shape from a root thereof to a top end thereof, a piezoelectric element formed on a side surface of the arm member and a protrusion additionally formed on an inside surface of the arm member near its top end section. The protrusion has tapered surfaces. Side surfaces of the head slider are adhered to the inside surfaces of the arm members at the protrusions and within regions between the protrusions and top ends of the arm members.

The servo signal recording device records a servo signal onto a magnetic tape. The device includes a transporting unit for transporting the magnetic tape along its lengthwise direction, a recording unit for recording the servo signal onto the transported magnetic tape, a detecting unit for detecting an edge of the magnetic tape at a time when the servo signal is recorded and an adjusting unit for adjusting a recording position of the servo signal along a crosswise direction of the magnetic tape in accordance with a detection result of the edge of the magnetic tape by the detecting unit. The servo signal verifying device verifies a servo signal recorded onto a magnetic tape. The device includes a reproducing unit for reproducing the servo signal, a detecting unit for detecting an edge of the magnetic tape at a time when the reproducing unit reproduces the servo signal and a calculating unit for calculating a verification result of the servo signal recorded onto the magnetic tape using a reproduction result of the servo signal and a detection result of the edge.