Patents Examined by Allen Heinz
  • Patent number: 8120875
    Abstract: A magnetic recording apparatus includes a magnetic recording head having a magnetic pole and a spin torque oscillator, the spin torque oscillator being placed adjacent to the magnetic pole and includes at least two magnetic layers of a first magnetic layer and a second magnetic layer, and a magnetic recording medium includes two magnetic layers of a recording layer and an antenna layer, the recording layer including a hard magnetic material, such that the antenna layer is formed closer to the magnetic recording head than the recording layer, in which the antenna layer has a resonance frequency fa lower than a resonance frequency fr of the recording layer, greater than a resonance frequency of the second magnetic layer, and the recording layer and the antenna layer are ferromagnetically coupled to each other.
    Type: Grant
    Filed: July 30, 2009
    Date of Patent: February 21, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masayuki Takagishi, Kenichiro Yamada, Hitoshi Iwasaki, Tomomi Funayama, Masahiro Takashita, Mariko Shimizu
  • Patent number: 8116034
    Abstract: When first and second near-field light-generating portions are irradiated with laser light or other energy rays, near-field light is generated at the tips of both the near-field light-generating portions. By means of the near-field light thus generated, a magnetic recording medium opposing the medium-opposing surface is heated, and the coercivity of the magnetic recording medium is lowered. Since at least a portion of the main magnetic pole is positioned within the spot region including the region between the first and second near-field light-generating portions, the tips of both the near-field light-generating portions and the main magnetic pole can be brought extremely close together, and high-density recording can be performed.
    Type: Grant
    Filed: September 4, 2008
    Date of Patent: February 14, 2012
    Assignee: TDK Corporation
    Inventors: Eiji Komura, Koji Shimazawa, Kosuke Tanaka, Seiichi Takayama, Hitoshi Hatate
  • Patent number: 8111479
    Abstract: A magnetic write head for perpendicular magnetic data recording having a trailing shield with a two step throat height. The trailing shield is formed over a non-magnetic bump that forms a notch in the leading edge of the trailing shield. This notch defines a first, smaller throat height closest to the write pole and a larger throat height away from the write pole. The smaller throat height near the write pole prevents excess magnetic flux from leaking to the write pole, thereby ensuring efficient strong write field. The larger trailing shield throat height away from the write pole prevents magnetic saturation of the trailing shield and also greatly facilitates manufacturing avoiding problems related to variations and deviations in manufacturing processes used to define the trailing shield.
    Type: Grant
    Filed: October 23, 2007
    Date of Patent: February 7, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Tsung Yuan Chen, Wen-Chien David Hsiao, Yimin Hsu, Vladimir Nikitin, Changqing Shi
  • Patent number: 8107202
    Abstract: A magnetoresistive sensor having an antiparallel coupled pinned layer structure including an AP1 layer and an AP2 layer. The AP2 layer includes two ferromagnetic layers AP2(a) and AP2(b), and a separation layer sandwiched therebetween. The AP2(a) layer is significantly larger than the AP2(b) layer, which results in strong pinning, while the separation layer provides increased TMR and reduced RA.
    Type: Grant
    Filed: December 30, 2008
    Date of Patent: January 31, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Wen-yaung Lee, Chang Man Park, Brian R. York, Alexander M. Zeltser
  • Patent number: 8107200
    Abstract: A slider mounted CPP GMR or TMR read head sensor is protected from electrostatic discharge (ESD) damage and from noise and cross-talk from an adjacent write head by means of a balanced resistive/capacitative shunt. The shunt includes highly resistive interconnections between upper and lower shields of the read head and a grounded slider substrate and a low resistance interconnection between the lower pole piece of the write head and the substrate. The capacitances between the pole piece and the upper shield, the upper shield and the lower shield and the lower shield and the substrate are made equal by either forming the shields and pole piece with equal surface areas and separating them with dielectrics of equal thicknesses, or by keeping the ratio of area to insulator thicknesses equal.
    Type: Grant
    Filed: June 19, 2008
    Date of Patent: January 31, 2012
    Assignees: Headway Technologies, Inc., SAE Magnetics (HK) Ltd.
    Inventors: Eric Cheuk Wing Leung, Anthony Wai Yuen Lai, Pak Kin Wong, David Hu, Moris Dovek, Rod Lee
  • Patent number: 8098464
    Abstract: A magnetic field detecting element includes: first and second free layers; a spacer layer; a first exchange coupling transmitting layer; a first pinned layer; a second exchange coupling transmitting layer; and a second pinned layer. The first and second pinned layers are magnetized in directions which are perpendicular to an air bearing surface and which are anti-parallel with each other, respectively. The first exchange coupling transmitting layer or second exchange coupling transmitting layer has a positive exchange coupling strength, while the other has a negative exchange coupling strength. The first or second pinned layer that is located adjacent to the first or second exchange coupling transmitting layer having the negative exchange coupling strength has a larger magnetic film thickness than the first or second free layer that is located adjacent to the first or second exchange coupling transmitting layer having the negative exchange coupling strength.
    Type: Grant
    Filed: February 19, 2008
    Date of Patent: January 17, 2012
    Assignee: TDK Corporation
    Inventor: Koji Shimazawa
  • Patent number: 8094409
    Abstract: A system and method for monitoring the helium content of a disk cavity of a hard disk drive is disclosed. In one embodiment of the present invention, an oxygen sensor is placed in the disk cavity to monitor the level of oxygen in the cavity. With the measurement of oxygen in the disk cavity, the level of helium in the cavity is inferred. In one embodiment, if the amount of helium inferred from the oxygen level fell below 90%-95% of the gaseous content of the disk cavity, a user is automatically notified in order to maintain the hard disk drive in a timely manner.
    Type: Grant
    Filed: May 28, 2008
    Date of Patent: January 10, 2012
    Assignee: Hitachi Global Storage Technologies, Netherlands B.v.
    Inventors: Norbert A. Feliss, Karl A. Flechsig
  • Patent number: 8094420
    Abstract: The invention provides a magnetoresistive device of the CCP (current perpendicular to plane) structure comprising a magnetoresistive unit sandwiched between soft magnetic shield layers with a current applied in the stacking direction. The magnetoresistive unit comprises a nonmagnetic intermediate layer sandwiched between ferromagnetic layers. A planar framework positions the soft magnetic shield layers and comprises a combination of a nonmagnetic gap layer with a bias magnetic field-applying layer constructed by repeating the stacking of a multilayer unit comprising a nonmagnetic underlay layer and a high coercive material layer. The nonmagnetic gap layer is designed and located such that a magnetic flux given out of the bias magnetic field-applying layer is efficiently directed along a closed magnetic path around the framework to form a single domain of magnetization.
    Type: Grant
    Filed: May 23, 2008
    Date of Patent: January 10, 2012
    Assignee: TDK Corporation
    Inventors: Toshiyuki Ayukawa, Takahiko Machita, Daisuke Miyauchi, Tsutomu Chou, Koji Shimazawa, Shinji Hara, Tomohito Mizuno, Yoshihiro Tsuchiya
  • Patent number: 8081400
    Abstract: A slider with an air-bearing surface includes an ID-side leading pad, an OD-side leading pad, an ID-side trailing pad, and an OD-side trailing pad. Each leading and trailing pad includes a respective pocket extending from the respective pad toward the air-bearing surface. The pockets each include a respective step surface surrounded by a trailing-side wall, an ID-side wall, and an OD-side wall. Each step surface has a respective depth, and each pocket is open to a leading side of the pocket. The slider further includes at least one cavity between the leading and trailing pads. The cavity includes a bottom surface of the slider having a cavity depth greater than all of the respective depths of the step surfaces of the pockets.
    Type: Grant
    Filed: August 29, 2008
    Date of Patent: December 20, 2011
    Assignee: Western Digital (Fremont), LLC
    Inventor: Yong Hu
  • Patent number: 8068309
    Abstract: The present disclosure provides a vibration damper for an actuator assembly. One exemplary embodiment relates to an actuator assembly including a magnetic assembly configured to produce a magnetic field and an actuator movable relative to the magnetic assembly in response to the magnetic field, wherein the actuator includes a vibration damper which interacts with the magnetic field.
    Type: Grant
    Filed: August 27, 2008
    Date of Patent: November 29, 2011
    Assignee: Seagate Technology LLC
    Inventors: Roy John MacKinnon, Larry Ernest Wittig, Jonathan Scott Haynes
  • Patent number: 8064165
    Abstract: Described herein are various embodiments of an electronic information storage apparatus and an associated method and system. For example, according to one illustrative embodiment, a disk drive comprises a base and at least one disk that are rotatably attached to the base. The at least one disk can include a burnished and lubricant-free outer surface. The disk drive can also include an actuator coupled to the base. The actuator can comprise a read/write head that is positionable in a reading/writing relationship with the at least one disk to define a lubricant-free space intermediate the read/write head and the outer surface. The disk drive can further include a read/write head loading and unloading ramp that is attached to the base. The ramp can include a ramp surface that is positioned proximate a periphery of the at least one disk.
    Type: Grant
    Filed: November 16, 2007
    Date of Patent: November 22, 2011
    Assignee: Hitachi Global Storage Technologies Netherland B.V.
    Inventor: Xing-Cai Guo
  • Patent number: 8059372
    Abstract: Biasing schemes used for CIP GMR devices were previously thought to be impractical for CPP devices due to current shunting by the abutted hard magnets. In the present invention the CPP stripe is a narrow conductor directly above the free layer. The resistivity of the latter is made to be relatively high so the sensing current diverges very little as it passes through it. This makes it possible to use abutted hard magnets for longitudinal bias with virtually no loss of sensing current due to shunting by the magnets.
    Type: Grant
    Filed: July 24, 2007
    Date of Patent: November 15, 2011
    Assignee: Headway Technologies, Inc.
    Inventors: Yimin Guo, Li-Yan Zhu
  • Patent number: 7408740
    Abstract: A thin-film magnetic head for perpendicular magnetic recording according to the present invention comprises a coil to generate a magnetic field, and a main pole layer to perform the perpendicular recording using the magnetic field generated by said coil. The lower surface as to the layer-forming direction of said main pole layer has irregularities at the medium-facing surface side end.
    Type: Grant
    Filed: April 21, 2005
    Date of Patent: August 5, 2008
    Assignees: Headway Technologies, Inc., SAE Magnetics (H.K.) Ltd.
    Inventors: Yoshitaka Sasaki, Takehiro Kamigama, Tatsushi Shimizu
  • Patent number: 7403359
    Abstract: A method is provided for inhibiting corrosion in a layer of Cu or other material in a GMR sensor, wherein the GMR sensor may be used in a magnetic data storage system such as a tape drive system to substantially improve read head sensitivity. The GMR sensor comprises stacked layers of ferromagnetic and non-magnetic materials. In one useful embodiment, a layer of Cu material is positioned between first and second layers of a specified ferromagnetic material, such as CoFe. Respective end surfaces of the Cu layer and first and second CoFe layers are initially located in substantially co-planar relationship with one another, in a common plane. The method further comprises etching the Cu layer to remove an amount of material therefrom. A new end surface is thus formed in the Cu layer, wherein the new end surface is selectively spaced apart from the common plane. A protective coating is then applied to the new end surface of the Cu layer, to inhibit corrosion of such layer.
    Type: Grant
    Filed: July 8, 2005
    Date of Patent: July 22, 2008
    Assignee: Storage Technology Corporation
    Inventors: John P. Nibarger, Herbert House
  • Patent number: 6891700
    Abstract: An HGA includes a magnetic head slider with at least one thin-film magnetic head element, a metal suspension for supporting the magnetic head slider, signal trace conductors formed via an insulation material layer on the metal suspension, for transmitting signals of the at least one thin-film magnetic head element, and external signal connection pads formed via an insulation material layer on the metal suspension and electrically connected to the signal trace conductors. At least part of the metal suspension under the external signal connection pads is removed.
    Type: Grant
    Filed: February 20, 2002
    Date of Patent: May 10, 2005
    Assignees: TDK Corporation, SAE Magnetics (H.K.) Ltd.
    Inventors: Masashi Shiraishi, Takeshi Wada, Takashi Honda
  • Patent number: 6882507
    Abstract: An integrated thin film head comprises, in order to prevent short-circuit among the lead layer, upper lead layer and shield layers, a lower shield layer formed on a substrate, a lower readgap layer formed on the lower shield layer, an MR sensor layer formed on the lower readgap layer, a lead layer jointed with the MR sensor layer, an upper lead layer formed in contact with a part of the lead layer, an upper readgap layer formed to cover the MR sensor layer, lead layer and upper lead layer and an upper shield layer formed on the upper readgap layer. The part of the lead layer in contact with the upper lead layer is formed thinner than the part not contact with the upper lead layer.
    Type: Grant
    Filed: December 20, 2000
    Date of Patent: April 19, 2005
    Assignee: Hitachi Global Storage Technologies, Japan, Ltd.
    Inventors: Kiyonori Shiraki, Tadashi Imanaka, Atsushi Kato, Matahiro Komuro
  • Patent number: 6880161
    Abstract: A cam structure is equipped with a first cam that displaces a first follower section in a radial direction, a second follower section that rotates with the first cam and has at least three support pins, and a second cam that displaces the second follower section in an axial direction. The first cam is formed from divided segments defining at least three arcuate surfaces with different radiuses and sloped connection surfaces that connect the arcuate surfaces and are provided in ranges that give appropriate pressure angles with respect to the first follower section, and the second cam is provided with cam sections, each of the cam sections being divided in the radial direction in the number corresponding to the number of the support pins. The divided cam sections of the second cam are disposed at positions arranged in a circumferential direction in a manner that displacements in the axial direction of the second follower section are timed with displacements in the radial direction of the first follower section.
    Type: Grant
    Filed: February 6, 2002
    Date of Patent: April 12, 2005
    Assignee: Tokyo Pigeon Co., Ltd.
    Inventor: Kunio Kido
  • Patent number: 6853517
    Abstract: A bidirectional electrostatic rotary microactuator has two sets of fixed electrodes, one set for driving the microactuator counterclockwise and the other set for driving it clockwise, and a rotatable frame that has movable electrodes attached to its outer wall and interleaved between the fixed electrodes. A layer of insulating material is located between the outer wall to which the movable electrodes are attached and the remainder of the frame so that the movable electrodes are electrically isolated. The frame is maintained at ground electrical potential and the movable electrodes at a fixed non-zero electrical potential. The microactuator is driven by applying a plus or minus voltage to one set of fixed electrodes and the opposite voltage to the other set, while maintaining the movable electrodes at a fixed non-zero voltage. The microactuator is usable as a secondary actuator in a disk drive for fine positioning the read/write head.
    Type: Grant
    Filed: February 13, 2003
    Date of Patent: February 8, 2005
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Toshiki Hirano, Henry Hung Yang