公开(公告)号：US20140334275A1

公开(公告)日：2014-11-13

申请号：US14339157

申请日：2014-07-23

Applicant: Seagate Technology LLC

Inventor： Xuan Zheng ,  Timothy William Stoebe ,  Jorge Hanchi ,  Kaizhong Gao

IPC: G11B5/60

CPC classification number: G11B5/607 ,  G11B5/6076 ,  G11B5/6088 ,  G11B2005/0021

Abstract: Changes in the thermal boundary condition near a close point of an ABS to a media indicate proximity of the ABS with the media. Before contact, heat conduction from the ABS is primarily through convective and/or ballistic heat transfer to air between the ABS and the media. After contact, heat flux primarily flows from the ABS to the media through solid-solid conductive contact. Further, a light source within a HAMR transducer head may create additional thermal variations within the transducer head. These thermal variations create temperature variations within the transducer head. Two resistance temperature sensors on the transducer head at varying distances from the close point and/or light source measure these temperature variations. A temperature difference between the two resistance temperature sensors indicates proximity of the close point to the media and/or light output.

Abstract translation: ABS附近接近介质的热边界条件的变化指示ABS与介质的接近。 在接触之前，ABS的热传导主要是通过ABS和介质之间的空气对流和/或弹道传热。 接触后，热通量主要通过固体导电接触从ABS流动到介质。 此外，HAMR换能器头内的光源可能在换能器头内产生额外的热变化。 这些热变化会导致传感器头内的温度变化。 传感器头上距离近点和/或光源不同距离的两个电阻温度传感器可测量这些温度变化。 两个电阻温度传感器之间的温差指示接近于介质和/或光输出的接近点。

公开(公告)号：US20140029402A1

公开(公告)日：2014-01-30

申请号：US14016645

申请日：2013-09-03

Applicant: Seagate Technology LLC

Inventor： Xuan Zheng ,  Timothy William Stoebe

IPC: G11B27/36

CPC classification number: G11B27/36 ,  B41J2/355 ,  G11B5/607 ,  G11B5/6076

Abstract: A data storage system includes a recording head and a compensating resistor. The recording head has a heating element. The compensating resistor is in electrical series with the heating element and is external to the recording head. A method includes applying an alternating current at a first angular frequency to a recording head. A voltage drop across the recording head heating element is measured. A component of the voltage drop is extracted. The component has a frequency that is three times the frequency of the first angular frequency.

Abstract translation: 数据存储系统包括记录头和补偿电阻。 记录头具有加热元件。 补偿电阻器与加热元件电连接并且在记录头的外部。 一种方法包括将第一角频率的交流电应用于记录头。 测量记录头加热元件两端的电压降。 提取电压降的分量。 该分量的频率是第一角频率的三倍。

公开(公告)号：US09818447B1

公开(公告)日：2017-11-14

申请号：US15464672

申请日：2017-03-21

Applicant: Seagate Technology LLC

Inventor： Xuan Zheng ,  Walter R. Eppler ,  Julius K. Hohlfeld ,  Heidi M. Olson

IPC: G11B5/02 ,  G11B27/36 ,  G11B20/18 ,  G11B5/012 ,  G11B7/126 ,  G11B5/00

CPC classification number: G11B20/1816 ,  G11B5/012 ,  G11B7/126 ,  G11B2005/0021

Abstract: A method comprises writing a waveform on a magnetic recording medium using a heat-assisted magnetic recording apparatus which includes a laser. The method also comprises reading back the waveform from the medium, and detecting one or more transition shifts in the readback waveform indicative of a mode hop of the laser. The method further comprises measuring a metric of the one or more transition shifts.

公开(公告)号：US08869590B2

公开(公告)日：2014-10-28

申请号：US13675798

申请日：2012-11-13

Applicant: Seagate Technology LLC

Inventor： Huiwen Liu ,  David Wobbe ,  Xuan Zheng ,  Timothy William Stoebe

IPC: G01N19/02 ,  G11B20/18

CPC classification number: G11B5/455 ,  G11B5/4806

Abstract: A flexible member is coupled between an actuator arm and a slider. The flexible member facilitates relative motion in a tangential direction of a rotating medium. The relative motion is detected via a displacement sensor, and a friction between the slider and the rotating medium is determined based on the sensed relative motion.

Abstract translation: 柔性构件联接在致动器臂和滑块之间。 柔性构件有助于在旋转介质的切线方向上的相对运动。 通过位移传感器检测相对运动，并且基于感测到的相对运动来确定滑块和旋转介质之间的摩擦。