Seagate Technology Incorporated

Joseph Cheng-Tsu Liu

Xiong Liu

Kevin Arthur Gomez

ChoonKiat Lim

Choon Kiat Lim

Michael Joo Chiang Toh

Zine-Eddine Boutaghou

Jing Gui

Bruno Jean Marchon

YiRen Hong

Niroot Jierapipatanakul

UttHeng Kan

Roger Alan Resh

WeiLoon Ng

Wai Onn Chee

Jianbo He

Chor Shan Cheng

Tao Zhang

Pow-Hing Yong

Michael Joo-Chiang Toh

Niroot Jierapipapatanakul

Wai Meng Chan

An apparatus for unloading a moveable member comprises a ramp structure with an inclined surface. A lift tab of the moveable member advances along the ramp structure to the inclined surface while pivoting about a pivot point to undergo an increase in elevation above a base surface. The inclined surface has a slope determined in relation to angular deflection of the lift tab induced by said increase in elevation. Preferably, the slope of the inclined surface substantially matches an angle of the lift tab when the lift tab is disposed on the inclined surface. The inclined surface preferably constitutes a parking surface, and the ramp structure further preferably comprises an entry/exit ramp surface and a latch surface along which the lift tab travels to reach the parking surface. The moveable member preferably comprises a flexible suspension which supports a transducer adjacent a data storage medium in a data storage device.

Ramp structure with inclined contact surface

Transducers are oriented differently to address the skew phenomenon. This enables a greater area of the medium to be utilized for data storage, thereby increasing the storage capacity of the device implementing embodiments of the present invention.

Slider having transducers orientated in different directions

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.

Method to achieve higher track density by allowing only one-sided track encroachment

A disc drive having a pivot cartridge and an actuator assembly. The actuator assembly consists of an actuator body which has a bore therein to receive the pivot cartridge. The actuator body further consists of an opening which serves as a ledge to engage a biased retaining ring. The biased retaining ring couples onto the pivot cartridge and forces the pivot cartridge to contact against one side of the bore of the actuator body.

Biased retaining ring for disc drive

An actuator control system for a two-stage actuator system of a disc drive has a first, or primary, stage actuator consisting of a voice coil motor that positions the head relative to a disc and a microactuator that alters the actuator system without operation of the voice coil motor. A control loop includes a controller responsive to seek commands to operate the voice coil motor, thereby moving the head relative to the disc. An active damping circuit is coupled to the head to operate the microactuator to damp resonance modes of the actuator system.

Active damping of two-stage actuator system in a disc drive

A disc drive includes a base and a disc rotatably attached to the base. The disc has an inner diameter and an outer diameter and a plurality of tracks. Information is written on the plurality of tracks. The plurality of tracks are written at a variable track pitch. The tracks positioned near the outer diameter are wider in pitch than the tracks positioned near the inner diameter. The plurality of tracks further include a first group of tracks written at a first track pitch, and a second group of tracks written at a second track pitch. The track pitch of each of the first group and the second group of tracks is selected such that the percentage of track misregistration for each group will be substantially the same. This method provides a means to increase storage capacity for a predetermined track misregistration budget.

Variable track densities on a recording medium to compensate for non-repeatable runout (NRRO) error

A disc drive is provided which incorporates a rotatable actuator which is mounted to a base of the disc drive through a pivot mechanism. The actuator positioning is controlled by a servo system and during track following operations, the actuator arm is caused to move. In one embodiment, the servo tracks incorporated in the disc drive are distorted when written in by the injection of a sinusoidal signal. In another form, the disc containing the servo information is caused to rotate about an axis which is offset from the disc axis. A method of creating a servo track is also disclosed.

System and method to minimize bearing pivot effect in disc drive actuator

An HDA includes a base, a disc stack coupled to a spindle rotatably attached to the base by a spindle shaft and spindle bearing. An actuator assembly is pivotally attached to the base at a pivot shaft. Attached to one end of the actuator assembly proximal the disc stack is one or more transducers for reading/writing information from/to the discs. A servo writer includes a controller for moving the actuator during the servo writing process. The controller moves the servo writer at the cage frequency of the spindle bearing to lessen the relative motion between the transducer head and the disc as the servo information is written to the disc. The controller also may be programmed to move the transducer at both the spindle rotation frequency and the cage frequency of the spindle bearing to lessen the relative motion between the transducer and the disc during the servo writing process.

Method and apparatus for reducing track misregistration from servo track writing

Disclosed is a method and apparatus for determining the dynamic characteristics of a desired component of an actuator assembly. Further, said method and apparatus are capable of determining the dynamic characteristics independent of any drive servo electronics. The system and method can also be used to determine other operating parameters such as rotational inertia. This information is useful for design verification, quality assurance and failure analysis.

Integrated test system for a disc drive pivot bearing and actuator

A pivot mechanism is disclosed for mounting a rotatable actuator on a base of a disc drive. The pivot mechanism is made up of a shaft on which a housing is rotatably mounted by a lower ball bearing set and an upper bearing provided by co-acting surfaces of the shaft and the housing.

Low friction bearing pivot for disc drive

There is provided an inertial latching system which includes a first latch member configured to engage a second latch member at a junction point. The first latch member includes a latch pivot mounted to the base. One side of the latch pivot extends to form a first arm whilst a balancing mass is found at another side of the latch pivot. Joined to the first arm is a finger which provides a contact line ending in a proximal point. The second latch member has a contact surface which provides a contact point. The inertial latching system is configured such that the ratio of a first length to a second length is smaller than the ratio of a third length to a fourth length. The first length is defined as the distance from the proximal point to the junction point, the second length is defined as the distance from the proximal to the latch pivot, the third length is defined as the distance from the contact point to the junction point, and the fourth length is defined as a distance from the contact point to the actuator pivot.

Disc drive actuator latch system for high rotational shock

The shock absorber apparatus for a disc drive is a molded polymeric enclosure adapted to receive and retain a disc drive. One preferred embodiment of the present invention has a shock absorbing material of a first thickness adjacent a critical region of the drive and a second thickness of shock absorbing material adjacent a non-critical region of the disc drive. The first thickness is greater than the second thickness in order to absorb a greater shock load to protect the critical region of the disc drive.

Wrap around shock absorber for disc drives

Non operational shock resistance is achieved by preventing separation of the read/write head from the disk. Embodiments include optimizing the normal stiction force of a lubricant topcoat by controlling the texture geometry of the landing zone and lubricant topcoat thickness, particularly the density of protrusions. Laser textured landing zones having a protrusion density above about 4,500 protrusions/mm.sup.2 can provide an optimal normal stiction force in excess of 25 gf per interface and a lateral stiction force below 10 gf per interface.

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Singapore, Singapore

Joseph Cheng-Tsu Liu