公开(公告)号：FI802902A

公开(公告)日：1981-03-18

申请号：FI802902

申请日：1980-09-16

Applicant: IBM

Inventor： LAMMERS GERALD BERNARD ,  SMITH GORDON JAMES

IPC: B41J2/01 ,  B41J2/025 ,  B41J2/075 ,  G06K15/10 ,  B41J

公开(公告)号：GB2344421A

公开(公告)日：2000-06-07

申请号：GB9927982

申请日：1999-11-29

Applicant: IBM

Inventor： OTTESEN HAL HJALMAR ,  SMITH GORDON JAMES

IPC: G11B5/55 ,  G11B5/596 ,  G11B21/16 ,  G01H13/00 ,  G11B5/58

Abstract: A method and apparatus for identifying and filtering a resonance frequency of a support structure 25 supporting a read/write head 27 in proximity with a data storage medium 24 involves obtaining a particular sample of a position error signal (PES) frequency transform, preferably using Goertzel's algorithm. The velocity of the data storage medium is varied, and the magnitude of a particular PES frequency transform sample is computed at each of the velocities. A resonance frequency of the support structure is calculated using the velocity associated with the particular sample having a maximum magnitude. The effects of one or more resonance frequencies associated with a read/write head suspension may be cancelled in a position error signal using one or more programmable filters provided in each servo loop. A processor programs the filters using the calculated resonance frequencies and adjusts to compensate for the additional lag introduced into the respective servo loops by the selected programmable filters. A method and apparatus for identifying one or more resonance frequencies of one or more read/write head support structures according to the principles of the present invention may be implemented in a data storage system and, preferably, implemented in-situ a data storage system without resort to circuitry external to the data storage system.

公开(公告)号：GB2267383B

公开(公告)日：1996-02-07

申请号：GB9308307

申请日：1993-04-22

Applicant: IBM

Inventor： OTTESEN HAL HJALMAR ,  SMITH GORDON JAMES

IPC: G11B5/00 ,  G11B5/09 ,  G11B5/012 ,  G11B5/035 ,  G11B5/39 ,  G11B19/04 ,  G11B20/10 ,  G11B5/02

Abstract: A method and system includes digitally linearizing a digital output signal originating from a magnetoresistive sensor by detecting the digital output signal originating from the magnetoresistive sensor. A linearization factor is then correlated to the digital output signal. Then, the digital output signal is modified the linearization factor to linearize the digital output signal.

公开(公告)号：GB2267383A

公开(公告)日：1993-12-01

申请号：GB9308307

申请日：1993-04-22

Applicant: IBM

Inventor： OTTESEN HAL HJALMAR ,  SMITH GORDON JAMES

IPC: G11B5/00 ,  G11B5/012 ,  G11B5/09 ,  G11B5/035 ,  G11B5/39 ,  G11B19/04 ,  G11B20/10 ,  G11B5/02

Abstract: A digital output signal originating from a magnetoresistive sensor 200 is digitally linearized by detecting the digital output signal originating from the magnetoresistive sensor and selecting one of a plurality of linearization factors correlated to the output signal. The linearization factors may be derived from a look-up table 214. The sensor 200 may be a read head of a disk drive system. In an arrangement with multiple heads, it is possible to equalise the gain of each head. It is also possible to maintain the gain constant regardless of changes in head or disk characteristics.

公开(公告)号：GB2344421B

公开(公告)日：2002-10-09

申请号：GB9927982

申请日：1999-11-29

Applicant: IBM

Inventor： OTTESEN HAL HJALMAR ,  SMITH GORDON JAMES

IPC: G11B5/55 ,  G11B5/596 ,  G11B21/16 ,  G01H13/00 ,  G11B5/58

Abstract: A method and apparatus for identifying and filtering a resonance frequency of a support structure supporting a read/write head in proximity with a data storage medium involves obtaining a particular sample of a position error signal (PES) frequency transform, preferably using Goertzel's algorithm. The velocity of the data storage medium is varied, and the magnitude of a particular PES frequency transform sample is computed at each of the velocities. A resonance frequency of the support structure is calculated using the velocity associated with the particular sample having a maximum magnitude. The effects of one or more resonance frequencies associated with a read/write head suspension may be canceled in a position error signal using one or more programmable filters provided in each servo loop. A processor programs the filters using the calculated resonance frequencies and adjusts to compensate for the additional lag introduced into the respective servo loops by the selected programmable filters. A method and apparatus for identifying one or more resonance frequencies of one or more read/write head support structures according to the principles of the present invention may be implemented in a data storage system and, preferably, implemented in-situ a data storage system without resort to circuitry external to the data storage system.

公开(公告)号：DE10110577A1

公开(公告)日：2001-10-04

申请号：DE10110577

申请日：2001-03-06

Applicant: IBM

Inventor： SMITH GORDON JAMES ,  LEEUWEN GEORGE WILLARD VAN

IPC: H04W4/02 ,  H04W4/024 ,  H04W4/029 ,  H04Q7/38 ,  H04L1/00

Abstract: If a mobile unit like a vehicle (301) gets near a communications dead zone (304), a telephone connection is automatically interrupted (305) but can be recovered (306) automatically if the mobile unit leaves the dead zone. During the controlled interruption the subscribers on the telephone connection receive an acoustic and/or optical message and/or a sensory stimulus to tell them that they are near a dead zone.

公开(公告)号：CA2138301C

公开(公告)日：1998-12-15

申请号：CA2138301

申请日：1994-12-15

Applicant: IBM

Inventor： OTTESEN HAL HJALMAR ,  CUNNINGHAM EARL A ,  GREENBERG RICHARD ,  BROWN DANA HENRY ,  SMITH GORDON JAMES ,  VANLEEUWEN GEORGE WILLARD ,  BILLINGS RUSSELL ALLEN

IPC: G11B5/012 ,  G11B5/55 ,  G11B5/596 ,  G11B7/0037 ,  G11B19/20 ,  G11B19/247 ,  G11B20/12 ,  G11B21/00 ,  G11B21/02 ,  G11B21/04 ,  G11B27/00 ,  G11B27/10 ,  H04N7/173

Abstract: A disk drive stores multimedia data in long spiral data tracks. The tracks on opposite surfaces of the disk spiral in opposite directions, so that a track on one surface can be read as the actuator sweeps in, and a track on the opposite surfa ce can be read as the actuator sweeps out. Because the actuator only follows spiral tracks without performing long seek operations, the actuator motor can be reduce d in size and stresses on actuator bearings and other parts are reduced. Additiona lly, due to reduced disturbances associated with seeks, it is possible to follow trac ks more closely and therefore reduce the width of individual tracks. Further cost reductions are accomplished by spinning the disks at a slower speed and reducing the size of the spin motor accordingly. Finally, data density can be increased s imply because multimedia data does not require the same low error rate as conventional data. Preferably, a group of disk drives optimized for multimedia data is used t o form a video-on-demand system. Compressed, interleaved portions of a video presentation, such as a motion picture, are stored in blocks on the spiral track s. The drives read the blocks on one spiral track at a time from beginning to end, placing the data from these blocks in a set of buffers corresponding to differen t short time intervals. Video signals are output from the buffers. Any short time interval of the presentation can be accessed on demand by switching to the appropriate buffer.

公开(公告)号：HK70396A

公开(公告)日：1996-05-03

申请号：HK70396

申请日：1996-04-25

Applicant: IBM

Inventor： OTTESEN HAL HJALMAR ,  SMITH GORDON JAMES

IPC: G11B5/00 ,  G11B5/09 ,  G11B5/012 ,  G11B5/035 ,  G11B5/39 ,  G11B19/04 ,  G11B20/10 ,  G11B5/02

Abstract: A method and system includes digitally linearizing a digital output signal originating from a magnetoresistive sensor by detecting the digital output signal originating from the magnetoresistive sensor. A linearization factor is then correlated to the digital output signal. Then, the digital output signal is modified the linearization factor to linearize the digital output signal.

公开(公告)号：DE3270939D1

公开(公告)日：1986-06-12

申请号：DE3270939

申请日：1982-02-17

Applicant: IBM

Inventor： SMITH GORDON JAMES

IPC: B41J2/18 ,  B41J2/185 ,  B41J2/20 ,  B41J3/04

Abstract: In an ink jet printing system wherein a drop generator emits ink droplets for printing on a recording medium, deleterious ink mist or ink dust formed as a result of ink droplets impacting on the medium is collected by collecting means disposed adjacent the zone at which the ink droplets contact the medium and airborne contamination, to components such as the drop generator, charge electrodes and deflection electrodes, are prevented by encasing the components in a pressurized container.In the Figure the print head 22 comprising drop generator 26, nozzle plate 28, charge electrode 31 and deflection plates 34, 36 are enclosed in container 40. The pressure in container 40 is maintained above atmosphereic via inlet 46, 48 from a pressure source. Ink droplets exitfrom the container 40 through aperture 50.A fog scoop 42 is mounted on the container and is connected to a low pressure suction source via outlet 86. A second outlet 92, 94 is connected to cavity 84 through a porous filter 90 and, in use, ink mist is condensed on the filter and re-circulated via outlet 92, 94.

公开(公告)号：DE69805462T2

公开(公告)日：2003-01-02

申请号：DE69805462

申请日：1998-01-16

Applicant: IBM

Inventor： BLACHEK MICHAEL DAVID ,  SMITH GORDON JAMES

IPC: G11B23/50 ,  G11B5/012 ,  G11B5/39 ,  G11B5/48 ,  G11B5/54 ,  G11B5/58 ,  G11B5/82 ,  G11B5/84 ,  G11B19/04 ,  G11B5/00

Abstract: Raised irregularities in a magnetic data storage disk are removed by contacting an MR head with the relatively softer irregularity to abrasively erode the irregularity. The MR head may be brought into contact with the irregularity, for example, by selectively increasing read bias current of the head to expand the head toward the disk. Advantageously, removal of such imperfections helps eliminate thermal asperities created when the head inadvertently contacts raised irregularities during reading of data.