G11B21/24

Z-HEIGHT CONTROL FOR DISC DRIVE USING SERVO WEDGE TIMING
20230260547 · 2023-08-17 ·

A data storage device includes a disc, an actuator arm assembly, a servo clock, and a feedback and control system. The disc includes a top and bottom surfaces and a servo wedge. The servo wedge includes a top surface boundary and a bottom surface boundary. The actuator arm assembly supports a head pair configured for interaction with the top and bottom surfaces. The servo clock is configured to determine a top time at which the head pair encounters the top surface boundary and a bottom time at which the head pair encounters the bottom surface boundary during a disc read/write interaction. The feedback and control system is configured to determine an operation time difference; compare the operation time difference to a certification time difference correlating to a target vertical position of the actuator arm assembly relative to the disc; and move the actuator arm assembly to the target vertical position.

Built-in resistance sensor for measuring slider level pole width at point “A” (PWA) for PMR/MAMR writers
11823712 · 2023-11-21 · ·

A PMR (perpendicular magnetic recording) write head is configured for measurements at the slider level and wafer-level processing stages that will allow a determination of the pole width at a position A (PWA) using the results of a resistance measurement between a main pole (MP) and surrounding write shields (WS) with a layer of conductor in the write gap and a layer of insulating material replacing the side gaps. Knowledge of an accurate value of PWA allows adjustments to be made in the processing of sliders on each rowbar which, in turn improves the capability of delivering the desired statistical variation (sigma) in the distribution of erasure widths for AC signals (EWACS) in a given design which, in turn, gives better overall performance in hard disk drive (HDD) applications.

Built-in resistance sensor for measuring slider level pole width at point “A” (PWA) for PMR/MAMR writers
11823712 · 2023-11-21 · ·

A PMR (perpendicular magnetic recording) write head is configured for measurements at the slider level and wafer-level processing stages that will allow a determination of the pole width at a position A (PWA) using the results of a resistance measurement between a main pole (MP) and surrounding write shields (WS) with a layer of conductor in the write gap and a layer of insulating material replacing the side gaps. Knowledge of an accurate value of PWA allows adjustments to be made in the processing of sliders on each rowbar which, in turn improves the capability of delivering the desired statistical variation (sigma) in the distribution of erasure widths for AC signals (EWACS) in a given design which, in turn, gives better overall performance in hard disk drive (HDD) applications.

Split ramp for data storage devices

A data storage device includes at least one head supported by an actuator arm. The at least one head interacts with the at least one data storage disc when positioned over the at least one data storage disc. The data storage device further includes a split ramp for supporting the at least one head when the at least one head is moved away from the at least one data storage disc. The split ramp has a first ramp portion adjacent to a first outer diameter (OD) of the at least one data storage disc and a second ramp portion adjacent to the first ramp portion, such that the first ramp portion is between the second ramp portion and the first OD. At least one of the first ramp portion or the second ramp portion is independently moveable.

Split ramp for data storage devices

A data storage device includes at least one head supported by an actuator arm. The at least one head interacts with the at least one data storage disc when positioned over the at least one data storage disc. The data storage device further includes a split ramp for supporting the at least one head when the at least one head is moved away from the at least one data storage disc. The split ramp has a first ramp portion adjacent to a first outer diameter (OD) of the at least one data storage disc and a second ramp portion adjacent to the first ramp portion, such that the first ramp portion is between the second ramp portion and the first OD. At least one of the first ramp portion or the second ramp portion is independently moveable.

Actuators for an elevator drive

A data storage device includes a base, a shaft that extends perpendicular from the base, and a head stack assembly (HSA) having a first end to which a head is coupled and a second end that is movably mounted on the shaft. The data storage device also includes either a first actuator assembly or a second actuator assembly. The first actuator assembly includes a first coil-permanent magnet assembly that rotatably moves the HSA about the shaft, and a second coil-permanent magnet assembly that serves as a first elevator to linearly move the HSA along the shaft. The second actuator assembly includes a third coil-permanent magnet assembly that rotatably moves the HSA about the shaft, and a second elevator that linearly moves the HSA along the shaft and also moves a data storage device ramp in unison with the HSA.

Actuators for an elevator drive

A data storage device includes a base, a shaft that extends perpendicular from the base, and a head stack assembly (HSA) having a first end to which a head is coupled and a second end that is movably mounted on the shaft. The data storage device also includes either a first actuator assembly or a second actuator assembly. The first actuator assembly includes a first coil-permanent magnet assembly that rotatably moves the HSA about the shaft, and a second coil-permanent magnet assembly that serves as a first elevator to linearly move the HSA along the shaft. The second actuator assembly includes a third coil-permanent magnet assembly that rotatably moves the HSA about the shaft, and a second elevator that linearly moves the HSA along the shaft and also moves a data storage device ramp in unison with the HSA.

Z-height control for disc drive using servo wedge timing

A data storage device includes a disc, an actuator arm assembly, a servo clock, and a feedback and control system. The disc includes a top and bottom surfaces and a servo wedge. The servo wedge includes a top surface boundary and a bottom surface boundary. The actuator arm assembly supports a head pair configured for interaction with the top and bottom surfaces. The servo clock is configured to determine a top time at which the head pair encounters the top surface boundary and a bottom time at which the head pair encounters the bottom surface boundary during a disc read/write interaction. The feedback and control system is configured to determine an operation time difference; compare the operation time difference to a certification time difference correlating to a target vertical position of the actuator arm assembly relative to the disc; and move the actuator arm assembly to the target vertical position.

Z-height control for disc drive using servo wedge timing

A data storage device includes a disc, an actuator arm assembly, a servo clock, and a feedback and control system. The disc includes a top and bottom surfaces and a servo wedge. The servo wedge includes a top surface boundary and a bottom surface boundary. The actuator arm assembly supports a head pair configured for interaction with the top and bottom surfaces. The servo clock is configured to determine a top time at which the head pair encounters the top surface boundary and a bottom time at which the head pair encounters the bottom surface boundary during a disc read/write interaction. The feedback and control system is configured to determine an operation time difference; compare the operation time difference to a certification time difference correlating to a target vertical position of the actuator arm assembly relative to the disc; and move the actuator arm assembly to the target vertical position.

Folded spring tape track following actuator

An apparatus for a spring actuator positioned in a folded spring actuator assembly includes a top section, a middle section, and a bottom section of the spring actuator that form a C-shape for the spring actuator. The middle section includes two parallelized spring legs, where a cable head module is slidable into a gap formed by the top section and two parallelized spring legs of the middle section of the spring actuator.