Patents by Inventor Timothy Francis Ellis

Timothy Francis Ellis has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7948704
    Abstract: A method is disclosed that includes measuring a first amplitude and a second amplitude in a servo pattern signal derived from a transducer head interacting with a medium; and providing an indication of a change in a spacing distance between the head and the medium, wherein the change in the spacing is evaluated using a spacing relation derived from a ratio of the first harmonic amplitude and the second harmonic amplitude.
    Type: Grant
    Filed: June 17, 2008
    Date of Patent: May 24, 2011
    Assignee: Seagate Technology LLC
    Inventor: Timothy Francis Ellis
  • Publication number: 20090153996
    Abstract: A method is disclosed that includes measuring a first amplitude and a second amplitude in a servo pattern signal derived from a transducer head interacting with a medium; and providing an indication of a change in a spacing distance between the head and the medium, wherein the change in the spacing is evaluated using a spacing relation derived from a ratio of the first harmonic amplitude and the second harmonic amplitude.
    Type: Application
    Filed: June 17, 2008
    Publication date: June 18, 2009
    Applicant: Seagate Technology LLC
    Inventor: Timothy Francis Ellis
  • Patent number: 7529051
    Abstract: An apparatus and method for compensation for variation in timing skew in a disc drive having at least one rotating disc is provided. A first head is positioned over a first disc surface and a second head is positioned over a second disc surface. The first disc surface includes a track having a first plurality of sectors and the second disc surface includes a track having a second plurality of sectors. Each sector of the second plurality of the sectors corresponds to a different sector of the first plurality of sectors, thereby forming a plurality of pairs of corresponding sectors. A timing skew value for each pair of corresponding sectors is computed to obtain a sequence of timing skew values. Data related to the sequence of timing skew values is utilized to compensate for variation in timing skew.
    Type: Grant
    Filed: December 18, 2002
    Date of Patent: May 5, 2009
    Assignee: Seagate Technology LLC
    Inventors: Reed David Hanson, Timothy Francis Ellis
  • Patent number: 7511912
    Abstract: Method and apparatus for certifying servo sectors on recording surfaces of a disc stack of a data storage device to promote servo sector alignment among the various recording surfaces. A reference servo sector pattern is written to a first recording surface, the reference pattern comprising a plurality of angularly spaced apart servo sectors. Multiple interleaved sets of servo sector patterns are written to each of the remaining recording surfaces, each interleaved pattern respectively comprising a plurality of angularly spaced apart servo sectors. A selected interleaved pattern is identified from each of the remaining surfaces that provides a desired alignment with the reference servo sector pattern, and the non-selected servo sector patterns are overwritten. The servo patterns can be written to the discs prior to installation using a multiple disc writing (MDW) station, or after installation of the discs into the data storage device using a servo track writing (STW) station.
    Type: Grant
    Filed: November 22, 2002
    Date of Patent: March 31, 2009
    Assignee: Seagate Technology LLC
    Inventors: Nathaniel Boyd Wilson, Reed David Hanson, Timothy Francis Ellis
  • Patent number: 7387848
    Abstract: A method of manufacturing a magnetic recording medium, comprises steps of providing a non-magnetic substrate for a magnetic medium, the substrate including at least one major surface having a contact start/stop (CSS) or landing zone and a data zone; and forming a pattern of recesses in the substrate surface in said CSS or landing zone by embossing utilizing a stamper having a surface including a negative image pattern of said pattern of recesses. Embodiments of the invention include magnetic media comprising a non-magnetic substrate including at least one major surface having a contact start/stop (CSS) or landing zone and a data zone, said substrate surface in said CSS or landing zone comprising an embossed pattern of recesses. In addition, the data zone of the substrate surface may include an embossed servo pattern formed simultaneously with the embossed pattern of recesses formed in the landing zone.
    Type: Grant
    Filed: August 18, 2003
    Date of Patent: June 17, 2008
    Assignee: Seagate Technology LLC
    Inventors: James Edward Angelo, Mukund Channagiri Rao, Alexei Hiram Sacks, Timothy Francis Ellis, David Kuo, Serge Jacques Fayeulle
  • Patent number: 7349167
    Abstract: An apparatus comprises a data storage medium having a plurality of servo sectors and a plurality of data sectors, wherein each of the servo sectors includes a phase locked loop field and a track identification field, a controller for controlling the position of a recording head with respect to the data storage medium, and a servo demodulator for recovering timing information from both the phase locked loop field and the track identification field, and for producing a timing estimate. The method performed by the apparatus is also included.
    Type: Grant
    Filed: July 27, 2005
    Date of Patent: March 25, 2008
    Assignee: Seagate Technology LLC
    Inventors: Mehmet Fatih Erden, Richard Lyle Keizer, Timothy Francis Ellis, Alexei Hiram Sacks
  • Patent number: 7092184
    Abstract: Using a “reference” sensor, a reference position is detected in a frame of reference that is moving along a predetermined path relative to the reference sensor. The reference position is used to derive a position-dependent indicator of a position-dependent “longitudinal” offset component (i.e. along the path). An output from the target sensor is monitored using a “target window” that is partially based on the position-dependent indicator.
    Type: Grant
    Filed: April 15, 2003
    Date of Patent: August 15, 2006
    Assignee: Seagate Technology LLC
    Inventors: Christopher Thomas Settje, David Louis Schell, Steven Alan Koldewyn, Reed Hanson, Timothy Francis Ellis
  • Patent number: 7064914
    Abstract: In a method for generating a confidence level of a position error signal (PES) component that is indicative of a quality of the PES component, a PES component is generated using position signal samples of a read back signal corresponding to a servo burst pattern. Next, a noise level corresponding to noise in the read back signal is extracted using the position signal samples. A confidence level is then generated based on the PES component and the noise level. A system for performing the method includes a transformation block, a position error signal (PES) component extractor, a noise extractor, and a confidence level generator. The transformation block is configured to receive position signal samples of a read back signal corresponding to a servo burst pattern taken at a sampling frequency. A transformed domain representation of the position signal samples is then generated by the transformation block based on the sampling frequency and the servo burst pattern.
    Type: Grant
    Filed: December 22, 2004
    Date of Patent: June 20, 2006
    Assignee: Seagate Technology LLC
    Inventors: Mehmet Fatih Erden, Richard L. Keizer, Alexei Hiram Sacks, Timothy Francis Ellis
  • Patent number: 6878426
    Abstract: A method of manufacturing a magnetic recording medium, comprises steps of providing a non-magnetic substrate for a magnetic medium, the substrate including at least one major surface having a contact start/stop (CSS) or landing zone and a data zone; and forming a pattern of recesses in the substrate surface in said CSS or landing zone by embossing utilizing a stamper having a surface including a negative image pattern of said pattern of recesses. Embodiments of the invention include magnetic media comprising a non-magnetic substrate including at least one major surface having a contact start/stop (CSS) or landing zone and a data zone, said substrate surface in said CSS or landing zone comprising an embossed pattern of recesses. In addition, the data zone of the substrate surface may include an embossed servo pattern formed simultaneously with the embossed pattern of recesses formed in the landing zone.
    Type: Grant
    Filed: September 25, 2003
    Date of Patent: April 12, 2005
    Assignee: Seagate Technology LLC
    Inventors: James Edward Angelo, Mukund Channagiri Rao, Alexei Hiram Sacks, Timothy Francis Ellis, David Kuo, Serge Jacques Fayeulle
  • Patent number: 6751045
    Abstract: A method and apparatus for compensating for repeatable run-out errors in a disc drive is disclosed. The compensation is created by determining transfer function values for a servo loop in the drive as well as a sequence of repeatable run-out values for a portion of a disc. The repeatable run-out values are divided by respective transfer function values to produce compensation values that are inverse transformed to produce time-domain compensation values. These time-domain compensation values are injected into the servo loop to compensate for repeatable run-out errors.
    Type: Grant
    Filed: January 12, 2000
    Date of Patent: June 15, 2004
    Assignee: Seagate Technology, LLC
    Inventors: John Christopher Morris, Brian Robert Pollock, Timothy Francis Ellis
  • Publication number: 20040100719
    Abstract: Method and apparatus for certifying servo sectors on recording surfaces of a disc stack of a data storage device to promote servo sector alignment among the various recording surfaces. A reference servo sector pattern is written to a first recording surface, the reference pattern comprising a plurality of angularly spaced apart servo sectors. Multiple interleaved sets of servo sector patterns are written to each of the remaining recording surfaces, each interleaved pattern respectively comprising a plurality of angularly spaced apart servo sectors. A selected interleaved pattern is identified from each of the remaining surfaces that provides a desired alignment with the reference servo sector pattern, and the non-selected servo sector patterns are overwritten. The servo patterns can be written to the discs prior to installation using a multiple disc writing (MDW) station, or after installation of the discs into the data storage device using a servo track writing (STW) station.
    Type: Application
    Filed: November 22, 2002
    Publication date: May 27, 2004
    Applicant: Seagate Technology LLC
    Inventors: Nathaniel Boyd Wilson, Reed David Hanson, Timothy Francis Ellis
  • Publication number: 20040058060
    Abstract: A method of manufacturing a magnetic recording medium, comprises steps of providing a non-magnetic substrate for a magnetic medium, the substrate including at least one major surface having a contact start/stop (CSS) or landing zone and a data zone; and forming a pattern of recesses in the substrate surface in said CSS or landing zone by embossing utilizing a stamper having a surface including a negative image pattern of said pattern of recesses. Embodiments of the invention include magnetic media comprising a non-magnetic substrate including at least one major surface having a contact start/stop (CSS) or landing zone and a data zone, said substrate surface in said CSS or landing zone comprising an embossed pattern of recesses. In addition, the data zone of the substrate surface may include an embossed servo pattern formed simultaneously with the embossed pattern of recesses formed in the landing zone.
    Type: Application
    Filed: September 25, 2003
    Publication date: March 25, 2004
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: James Edward Angelo, Mukund Channagiri Rao, Alexi Hiram Sacks, Timothy Francis Ellis, David Kuo, Serge Jacques Fayeulle
  • Publication number: 20040050480
    Abstract: A method of manufacturing a magnetic recording medium, comprises steps of providing a non-magnetic substrate for a magnetic medium, the substrate including at least one major surface having a contact start/stop (CSS) or landing zone and a data zone; and forming a pattern of recesses in the substrate surface in said CSS or landing zone by embossing utilizing a stamper having a surface including a negative image pattern of said pattern of recesses. Embodiments of the invention include magnetic media comprising a non-magnetic substrate including at least one major surface having a contact start/stop (CSS) or landing zone and a data zone, said substrate surface in said CSS or landing zone comprising an embossed pattern of recesses. In addition, the data zone of the substrate surface may include an embossed servo pattern formed simultaneously with the embossed pattern of recesses formed in the landing zone.
    Type: Application
    Filed: August 18, 2003
    Publication date: March 18, 2004
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: James Edward Angelo, Mukund Channagiri Rao, Alexi Hiram Sacks, Timothy Francis Ellis, David Kuo, Serge Jacques Fayeulle
  • Publication number: 20040021971
    Abstract: An apparatus and method for compensation for variation in timing skew in a disc drive having at least one rotating disc is provided. A first head is positioned over a first disc surface and a second head is positioned over a second disc surface. The first disc surface includes a track having a first plurality of sectors and the second disc surface includes a track having a second plurality of sectors. Each sector of the second plurality of the sectors corresponds to a different sector of the first plurality of sectors, thereby forming a plurality of pairs of corresponding sectors. A timing skew value for each pair of corresponding sectors is computed to obtain a sequence of timing skew values. Data related to the sequence of timing skew values is utilized to compensate for variation in timing skew.
    Type: Application
    Filed: December 18, 2002
    Publication date: February 5, 2004
    Inventors: Reed David Hanson, Timothy Francis Ellis
  • Publication number: 20040021972
    Abstract: Using a “reference” sensor, a reference position is detected in a frame of reference that is moving along a predetermined path relative to the reference sensor. The reference position is used to derive a position-dependent indicator of a position-dependent “longitudinal” offset component (i.e. along the path). An output from the target sensor is monitored using a “target window” that is partially based on the position-dependent indicator.
    Type: Application
    Filed: April 15, 2003
    Publication date: February 5, 2004
    Inventors: Christopher Thomas Settje, David Louis Schell, Steven Alan Koldewyn, Reed Hanson, Timothy Francis Ellis
  • Patent number: 6678110
    Abstract: A robust and efficient method for determining the location of a transducer head in a mass storage system. A position-indicative signal characterized by a fundamental frequency F is received from a data path including the transducer head. Energy in the signal at frequencies smaller than F/10 is substantially attenuated by a special filter, which may be an analog or digital differentiator. A sequence of bits indicative of the transducer head position indicator is then extracted from the digitized, filtered signal.
    Type: Grant
    Filed: March 30, 2001
    Date of Patent: January 13, 2004
    Assignee: Seagate Technology LLC
    Inventor: Timothy Francis Ellis
  • Patent number: 6627254
    Abstract: A method of manufacturing a magnetic recording medium, comprises steps of providing a non-magnetic substrate for a magnetic medium, the substrate including at least one major surface having a contact start/stop (CSS) or landing zone and a data zone; and forming a pattern of recesses in the substrate surface in said CSS or landing zone by embossing utilizing a stamper having a surface including a negative image pattern of said pattern of recesses. Embodiments of the invention include magnetic media comprising a non-magnetic substrate including at least one major surface having a contact start/stop (CSS) or landing zone and a data zone, said substrate surface in said CSS or landing zone comprising an embossed pattern of recesses. In addition, the data zone of the substrate surface may include an embossed servo pattern formed simultaneously with the embossed pattern of recesses formed in the landing zone.
    Type: Grant
    Filed: September 17, 2001
    Date of Patent: September 30, 2003
    Assignee: Seagate Technology LLC
    Inventors: James Edward Angelo, Mukund Channagiri Rao, Alexei Hiram Sacks, Timothy Francis Ellis, David Kuo, Serge Jacques Fayeulle
  • Patent number: 6556933
    Abstract: A data handling system that effectively detects and diagnoses manifestations of excessive transducer instability. For example, some embodiments identify shouldering and baseline pop instabilities in a digital servo channel. A preferred method of the present invention involves detecting a precise time at which a first feature in the received signal is encountered. Then, after a preset delay, a first level of the received signal is sampled. Then, after waiting until after a second feature in the received signal occurs, a second level of the received signal is sampled. Finally, at least one digital signal is generated so as to indicate whether an arithmetic combination of the first and second levels falls outside a stability-indicative range. A preferred device of the present invention includes a transducer, a peak detector configured to receive a signal from the transducer, two delay elements, two sampling circuits, and an output.
    Type: Grant
    Filed: October 27, 2000
    Date of Patent: April 29, 2003
    Assignee: Seagate Technology LLC
    Inventors: Alexei Hiram Sacks, Timothy Francis Ellis
  • Publication number: 20020141105
    Abstract: A robust and efficient method for determining the location of a transducer head in a mass storage system. A position-indicative signal characterized by a fundamental frequency F is received from a data path including the transducer head. Energy in the signal at frequencies smaller than F/10 is substantially attenuated by a special filter, which may be an analog or digital differentiator. A sequence of bits indicative of the transducer head position indicator is then extracted from the digitized, filtered signal.
    Type: Application
    Filed: March 30, 2001
    Publication date: October 3, 2002
    Inventor: Timothy Francis Ellis
  • Patent number: 6069764
    Abstract: A method and apparatus for compensating for repeatable run-out errors in a disc drive is disclosed. The compensation is created by determining transfer function values for a servo loop in the drive as well as a sequence of repeatable run-out values for a portion of a disc. The repeatable run-out values are divided by respective transfer function values to produce compensation values that are inverse transformed to produce time-domain compensation values. These time-domain compensation values are injected into the servo loop to compensate for repeatable run-out errors.
    Type: Grant
    Filed: June 29, 1998
    Date of Patent: May 30, 2000
    Assignee: Seagate Technology, Inc.
    Inventors: John Christopher Morris, Brian Robert Pollock, Timothy Francis Ellis