| Patent Number |
Title Of Patent |
Date Issued |
| 8233232 |
Method and data storage device with a snubber supported on an actuator and having a distal edge |
July 31, 2012 |
| A data storage apparatus and associated method is provided involving a data storage disc that is rotatable around a first axis. An actuator is rotatable around a second axis to operably position a data transfer member between an innermost radial location of the data storage disc and |
| 8120868 |
Data storage medium having system data stored in a guard band between zones of consecutive data |
February 21, 2012 |
| A storage medium format is provided having a first band of a plurality of consecutive data storage tracks having user data stored thereto, a second band of a plurality of consecutive data storage tracks having other user data stored thereto, and a guard track medially disposed therebetwe |
| 7891249 |
Multi-axis vibration method and apparatus |
February 22, 2011 |
| A vibration test apparatus is disclosed. The vibration test apparatus includes a platform assembly, which receives a vibration input from a vibration source and imparts a multi-axial vibration to a test specimen on the platform assembly. In illustrated embodiments the platform assemb |
| 7872827 |
Impact protection for a retractable control object |
January 18, 2011 |
| Various embodiments of the present invention are generally directed to protecting a device from damage due to an impact event at the conclusion of a free fall condition through the use of a biasing signal that maintains a retention force until the impact event is completed. |
| 7675712 |
Ramp structure with inclined contact surface |
March 9, 2010 |
| 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 |
| 7532437 |
Slider having transducers orientated in different directions |
May 12, 2009 |
| 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. |
| 7483238 |
Shock absorbing device for an enclosure |
January 27, 2009 |
| A shock absorbing device for an enclosure. The shock absorbing device including a shock absorbing frame. The shock absorbing frame includes an inner surface coupled adjacent to the enclosure and an outer surface. The shock absorbing device also includes a plurality flexible shock bumpers |
| 7457075 |
System and method for reducing ZAP time and track squeeze in a data storage device |
November 25, 2008 |
| A method and apparatus for compensating for errors in servo systems. An improved zero acceleration path (ZAP) correction technique is provided, wherein selected tracks of a data storage device are used for ZAP processing in order to reduce the overall time required to perform error c |
| 7405893 |
Data storage medium with optimized servo format |
July 29, 2008 |
| A data storage medium and data storage system with improved efficiency of formatting are provided. One illustrative embodiment of the present invention pertains to a data storage medium. The data storage medium includes a first zone having servo information written with a first frequ |
| 7352523 |
Ramp unload in disc drives |
April 1, 2008 |
| Embodiments of the present invention provide for apparatus and methods for performing unload operations, including enabling read/write heads to reach a desired velocity at the ramp. Embodiments of the present invention are particularly beneficial for handheld products where low power |
| 7349174 |
Soft sensor for operating shock in a disc drive |
March 25, 2008 |
| A method of preventing a write operation to a disc in a disc drive during a shock event without the use of a separate shock sensor comprises steps of monitoring an actuator voice coil motor (VCM) control plant output signal, generating an actuator voice coil motor (VCM) plant model modul |
| 7330328 |
Random number generation using back electromotive force (BEMF) values |
February 12, 2008 |
| Method and apparatus for generating a random number, such as for use in a security protocol to control access to a data processing system. A processor generates the random number in relation to a back electromotive force (BEMF) value. The BEMF value is preferably obtained in response to |
| 7328118 |
Method of determining the mass unbalance of an actuator |
February 5, 2008 |
| The present invention is a method of determining mass unbalance of an actuator mechanism in a system. The method includes calculating a center of gravity in first x and y components with respect to a first coordinate system of the actuator mechanism. The method also includes calculating |
| 7259933 |
Velocity control system for an actuator assembly |
August 21, 2007 |
| A method for generating a velocity command for an actuator assembly is provided. The actuator assembly includes an actuator arm, which is to move over a plurality of surfaces. The method begins by providing a compensation torque for each of the plurality of surfaces. A position of th |
| 7167882 |
True random number generation |
January 23, 2007 |
| True random numbers are generated from position error signals or like signals. The generator is not dependent on a potentially biased reference or threshold, and is capable of quickly generating true random numbers on demand. The present invention can be implemented as an integral fu |
| 7082007 |
Method to achieve higher track density by allowing only one-sided track encroachment |
July 25, 2006 |
| 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 p |
| 6954325 |
Method and disc drive for writing servo wedges |
October 11, 2005 |
| A method and disc drive are disclosed that write servo wedges to a plurality of tracks of a disc. A head having a read element offset from a write element reads a servo wedge on a first track as a propagation guide and writes two or more servo wedges to be used as a subsequent propagatio |
| 6937427 |
Method and apparatus for measuring the back EMF of a disc drive VCM |
August 30, 2005 |
| An apparatus and method of measuring a back electromotive force (BEMF) voltage of a disc drive voice coil motor (VCM) is provided in which a temperature of the VCM is obtained. The BEMF voltage of the VCM is computed as a function of the temperature of the VCM. |
| 6862155 |
Squeeze evaluations that account for low frequency components, in a controller usable in a data |
March 1, 2005 |
| Position error values are obtained from a transducer head while following a plurality of servo tracks with a servo loop that band-blocks a frequency range that includes F, a nominal rotation frequency. An estimated difference distribution is derived from the position error values, the |
| 6856485 |
Biased retaining ring for disc drive |
February 15, 2005 |
| 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 |
| 6853511 |
Average position error measurement in a data storage device |
February 8, 2005 |
| A number of data pairs, each data pair comprises a write-to-read track misregistration (WRTMR) value and an average position error margin (APE) value, are determined for a data storage device. Each of the data pairs is associated with a unique predetermined non-repeatable runout (NRRO) e |
| 6829115 |
Method and apparatus for measuring half frequency whirl in a spindle motor |
December 7, 2004 |
| An apparatus and method of indirectly measuring half frequency whirl in a spindle motor having a rotor adapted to rotate a disc having a track which is followed by a transducer head that is actuated by a control system is provided. Vibration signals produced at the transducer head while |
| 6771441 |
Track mis-registration measurement for a disc drive |
August 3, 2004 |
| An apparatus and method of predicting functional capability of a data storage device having a plurality of information tracks, comprising performing a DC erase on three adjacent information tracks, writing a predetermined bit pattern on a middle track of the three adjacent informatio |
| 6765737 |
Variable track densities on a recording medium to compensate for non-repeatable runout (NRRO) er |
July 20, 2004 |
| 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 |
| 6754030 |
Optimal reader-to-writer offset measurement of a head in a disc drive for reduced track misregis |
June 22, 2004 |
| A method of and apparatus for generating a reader-to-writer offset for a head positioned over a track on a disc in a disc drive having a plurality of tracks is disclosed. A reader and a writer are mounted on the head in a non-overlapping manner with a gap between the reader and the write |
| 6687094 |
Head actuator for a data storage head having a low mass with lateral stiffness |
February 3, 2004 |
| An actuator having a relatively low mass for supporting flexible head suspension assemblies to read data from or write data to discs. The actuator includes an actuator body adapted to rotationally coupled to a base chassis of the disc drive and a yoke assembly including yoke arms ext |
| 6661614 |
Magnetless actuator for disc drive |
December 9, 2003 |
| A magnetless rotary actuator for carrying one or more read/write heads across a data bearing medium, the rotary actuator comprising: a stator including a plurality of independently controllable flux generating means for directing flux between the stator and a rotor; the rotor including |
| 6654198 |
Repeatable run-out error compensation method for a disc drive |
November 25, 2003 |
| Steps for isolating and correcting total written-in repeatable run-out error written into servo sectors of a disc drive include, determining a total repeatable run-out error value for each servo sector, isolating a repeatable error value component of the total written-in repeatable r |
| 6628471 |
Detection and cancellation of cage frequency using the clock head in a servowriter |
September 30, 2003 |
| The magnitude and frequency of runout due to vibration of the cage of the spindle motor is detected. A plurality of servo patterns are written to a reference track having a clock pattern on the disc, and the plurality of servo patterns are then read over a plurality of revolutions of the |
| 6606214 |
System and method to minimize bearing pivot effect in disc drive actuator |
August 12, 2003 |
| 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 embodime |
| 6590739 |
Disc clamp with shape memory alloys |
July 8, 2003 |
| A disc clamp made from a shape memory alloy is configured for tight fit between an upper ledge of a spindle hub and the upper surface of a disc when the disc clamp is in an austenitic phase. In a martensitic phase, the disc clamp is configured for easy assembly over the spindle hub. The |
| 6487035 |
Method and apparatus for adaptive feedforward cancellation |
November 26, 2002 |
| A method and apparatus are provided for generating an adaptive feedforward cancellation signal for a next sector of a disc in a disc drive. The cancellation signal includes at least one tap weight multiplied by at least one trigonometric function. To form the cancellation signal, the |
| 6476995 |
Method and apparatus for reducing track misregistration from servo track writing |
November 5, 2002 |
| 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 |
| 6453722 |
Integrated test system for a disc drive pivot bearing and actuator |
September 24, 2002 |
| 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 |
| 6414817 |
High friction disc support member to increase disc drive mechanical shock resistance |
July 2, 2002 |
| Apparatus in a disc drive for improving resistance of a disc drive disc stack to radially directed mechanical shocks. A disc is disposed about a rotatable spindle motor hub. Opposing first and second disc support members (such as a disc clamp, disc spacers, or a hub flange) circumfer |
| 6411471 |
Low friction bearing pivot for disc drive |
June 25, 2002 |
| 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. |
| 6256173 |
Apparatus for isolating vibration in pivot bearing assemblies |
July 3, 2001 |
| An apparatus for isolating vibration in pivot bearing assemblies that is incorporated in a standard pivot bearing assembly without requiring modification of the pivot bearing assembly. Washers are used between the pivot bearing assembly and the base plate of a disc drive upon which the |
