Between Heads In Alternate Engagement With Medium Patents (Class 360/64)
  • Publication number: 20030234998
    Abstract: New helical recording scanner architectures and transducing methods provide a consistent track pitch for helical tracks despite positional errors in placement of transducing elements (or sets of transducing elements) from their nominal positioning. The new scanners (85) are rotatable scanners having a vertical direction parallel to an axis of rotation of the scanner. Both first and second transducing elements are mounted on the scanner, and a tape drive (30) which comprises the scanner also includes a transport system for transporting magnetic tape (31) proximate the rotatable scanner in a manner so that information is transduced in helical tracks by the transducing elements during revolutions of the scanner.
    Type: Application
    Filed: May 20, 2003
    Publication date: December 25, 2003
    Inventor: Steven L. Magnusson
  • Patent number: 6639747
    Abstract: The present invention relates to a signal recording and reproducing method used for video tape recorder. An erasing position precedes a recording position and a reproducing position precedes the erasing position. By using a period when reproducing does not reproduce a signal recorded on a track of a tape-like storage medium, the period occurring during recording and reproducing operation, recording apparatus records a signal on a recording track or erasing apparatus erases a signal recorded on a recording track. Hereby, if a signal recorded on a recording track of the tape-like storage medium is processed and replaced, the signal recorded on the recording track of the tape-like storage medium can be satisfactorily reproduced without being influenced by signal recording operation and signal erasing operation.
    Type: Grant
    Filed: August 2, 1999
    Date of Patent: October 28, 2003
    Assignee: Sony Corporation
    Inventors: Hiroyuki Asakura, Hideaki Kondo
  • Patent number: 6621981
    Abstract: A recording/reproducing apparatus or a reproducing apparatus has a first, a second and a third magnetic heads. The first and second magnetic heads have different gap azimuth angles and are spaced 180 degrees apart from each other on a rotary head. The third magnetic head has the same gap azimuth angle as that of the second magnetic head and a specific relative positional relationship with the first magnetic head on the rotary head. Recording of each frame signal of a video signal is controlled as follows: The frame signal is divided into N (N being a integer of two or more) slant tracks on a magnetic tape at a standard tape speed in a standard mode; the frame signal is divided into N/2 slant tracks at a tape speed ½ of the standard speed in ½ speed mode; or the frame signal is divided into N/2 slant tracks at a tape speed ⅓ of the standard speed in ⅓ speed mode.
    Type: Grant
    Filed: April 8, 1999
    Date of Patent: September 16, 2003
    Assignee: Victor Company of Japan, Ltd.
    Inventor: Yoshio Tokuyama
  • Patent number: 6618216
    Abstract: One aspect of the invention is a digital audio tape (DAT) drive having a plurality of read and write heads. Each of the read and write heads has its own parameters, such as a cut-off frequency and a boost value of a read head, a write current of a write head, etc. The parameters of each head are stored in registers and used when an electrical signal representing digital data is to be written to or read from a magnetic tape is processed. When the electrical signal to be written or to have been read by a specific head is processed, the parameters of the specific head will be provided to an equalizer or a pre-amplifier. In the reading process, because the optimum cut-off frequency and boost value are used for a specific read head, the processed electrical signal more accurately represents the digital data recorded on the magnetic tape. In the writing process, the optimum write current to a specific write head makes the write head generate a sufficient magnetic field to magnetize the write head.
    Type: Grant
    Filed: July 16, 1998
    Date of Patent: September 9, 2003
    Assignee: Mitsumi Electric Co., Ltd.
    Inventor: Masayuki Kitagawa
  • Publication number: 20030095352
    Abstract: The present invention relates to a signal recording and reproducing method used for video tape recorder. An erasing position precedes a recording position and a reproducing position precedes the erasing position. By using a period when reproducing means does not reproduce a signal recorded on a track of a tape-like storage medium, the period occurring during recording and reproducing operation, recording means records a signal on a recording track or erasing means erases a signal recorded on a recording track. Hereby, if a signal recorded on a recording track of the tape-like storage medium is processed and replaced, the signal recorded on the recording track of the tape-like storage medium can be satisfactorily reproduced without being influenced by signal recording operation and signal erasing operation.
    Type: Application
    Filed: August 2, 1999
    Publication date: May 22, 2003
    Applicant: Sony Corporation
    Inventors: HIROYUKI ASAKURA, HIDEAKI KONDO
  • Patent number: 6553455
    Abstract: A method and apparatus for providing passed pointer detection in audio/video streams on disk media. The present invention sets up an audio/video stream on a disk drive, uses read and write commands for accessing contiguous data and provides a pointer system that provides a warning when manipulating the pointers during fast forward and reverse functions that one pointer has passed the other. The position of a first pointer and a second pointer in at least one stream is monitored during a command execution. A determination is made when the positions of the first and second pointers cross to create a passed pointer state. An indicator is set to signal that a passed pointer state has occurred. The passed pointer indicator is then used to prevent anomalous behavior in processing of the at least one stream.
    Type: Grant
    Filed: September 26, 2000
    Date of Patent: April 22, 2003
    Assignee: International Business Machines Corporation
    Inventors: Hideo Asano, Daniel James Colegrove, Akira Kibashi, Masahiko Sato
  • Patent number: 6549356
    Abstract: There is provided a rotary drum which is capable of increasing recording density of a magnetic tape by changing tape/head relative speed and by solving problems which occur in increasing the tape/head relative speed. The inventive rotary drum includes a pair of recording heads having different azimuth angles and disposed separately with 180° of central angle and a second recording head disposed at the same position in the circumferential direction with one recording head among the pair of recording heads while separating by 5.5 &mgr;m in the direction of height of the rotary drum and having a different azimuth angle from the one recording head. A first mode is created by the pair of recording heads separated by 180° of central angle and a second mode is created by the two recording heads at the same position in the circumferential position.
    Type: Grant
    Filed: November 2, 2000
    Date of Patent: April 15, 2003
    Assignee: Sony Corporation
    Inventors: Tadashi Ozue, Toshio Shirai
  • Patent number: 6542322
    Abstract: In a rotary head apparatus a first reproducing magnetic head and a second reproducing magnetic head are oppositely arranged between a rotating shaft; and a first recording magnetic head and a second recording magnetic head are also oppositely arranged between the rotating shaft. One of the magnetic head elements of the first recording magnetic head and one of the magnetic head elements of the second recording magnetic head are connected to a first channel of a rotary transformer; and the other magnetic head element of the first recording magnetic head and the other magnetic head element of the second recording magnetic head are connected to a second channel of the rotary transformer, to thereby enable simultaneous recording and reproducing.
    Type: Grant
    Filed: May 10, 1999
    Date of Patent: April 1, 2003
    Assignee: Alps Electric Co., Ltd.
    Inventor: Kenji Maemine
  • Publication number: 20030048563
    Abstract: A helical scan tape recorder (30) comprises a rotatable scanner (85) upon which is mounted a first set of plural transducing heads (W1, W3) and a second set of transducing heads (W2, W4). A transport system transports magnetic tape (31) proximate the rotatable scanner in a manner so that information is transduced by at least one of the transducing heads during a revolution of the scanner. The sets of transducing heads are so mounted on the scanner with respect to azimuthal orientation of the transducing heads that all tracks transduced by the transducing heads have a desired width regardless of an error in physical distance separating the sets of transducing heads. In one aspect, the first set of plural transducing heads comprises a first head (W1) and a third head (W3), and the second set of plural transducing heads comprises a second head (W2) and a fourth head (W4).
    Type: Application
    Filed: April 25, 2002
    Publication date: March 13, 2003
    Inventors: Steven L. Magnusson, Timothy C. Hughes
  • Patent number: 6523747
    Abstract: An apparatus for reading permanently structured magnetic records having a first coercivity, comprising an oscillator having an inductive read head that is coupled to a circuit arrangement. At least one side of the read head sees an impedance that is larger than the impedance of the read head over the range of frequencies of interest, such that the read head provides an electrical signal in response to magnetic records having a second coercivity that is higher than the first coercivity (typically 2,000 to 5,000 oersteds). The electrical signal is derived from the voltage across the read head, which is preferably detected by a differential integrator that subtracts the voltages on either side of the read head to give a voltage difference, and integrates this difference over time.
    Type: Grant
    Filed: January 27, 2000
    Date of Patent: February 25, 2003
    Assignee: Central Research Laboratories Limited
    Inventor: Ian Macdonald Green
  • Patent number: 6476993
    Abstract: A compact rotary transformer is disclosed. In the structure of the rotary transformer, a timing-signal producing unit detects a control signal superimposed on an electric power signal output from a power transmission channel of the rotary transformer to produce a timing signal. A head-switching-signal generating unit uses the timing signal to generate a switching signal for performing switching between reproducing heads so that one of the reproducing heads is selected by a switch. A reproduction channel of the rotary transformer outputs a reproducing signal via the switch.
    Type: Grant
    Filed: June 15, 2000
    Date of Patent: November 5, 2002
    Assignee: Sony Corporation
    Inventor: Yoji Aoki
  • Publication number: 20020114094
    Abstract: An apparatus for detecting an abnormality of a recorded signal of a recorder/player includes a plurality of recording/reproducing heads for recording/reproducing a signal onto/from a medium, and a determining portion for determining an abnormality of the recorded signal based on the signal reproduced by the recording/reproducing heads. While one recording/reproducing head records the signal of image and/or sound on the medium, the other recording/reproducing head reproduces the signal recorded by the recording/reproducing head. The determining portion determines the abnormality of the recorded signal by determining whether or not the signal reproduced from the medium is in a normal data format, or by determining whether or not an envelope of reproduced signals is greater than a predetermined level. Accordingly, when abnormality of recorded signal occurs due to a presence of foreign substances on the heads or from other problem sources, a user is immediately notified of such an abnormality.
    Type: Application
    Filed: February 22, 2001
    Publication date: August 22, 2002
    Inventor: Chang-Hyeon Lee
  • Patent number: 6433945
    Abstract: A transformer-coupled tape drive (30) allows operation using a direct current (DC) content code. Usage of the DC content code is facilitated by a compensation circuit (240) which corrects timing distortion caused by the DC content code. The compensation circuit comprises both an emulation circuit (306) and a delay circuit (302). The emulation circuit (306) emulates a high pass filter action of a transformer (220) to provide an emulated high pass filter response signal (WD_HP). The delay circuit (302) modifies the modify timing of the write data signal in accordance with the emulated high pass filter response signal to output a compensated write data signal to the transformer (220).
    Type: Grant
    Filed: November 9, 2000
    Date of Patent: August 13, 2002
    Assignee: Exabyte Corporation
    Inventor: David E. Norton, Jr.
  • Publication number: 20020080519
    Abstract: In a helical scan recording system, magnetic tape (31) is transported by a tape transport (98) proximate a rotating scanner (85). The scanner has a pair of read heads (82) mounted thereon, e.g., a first read head and a second read head, which travel in a helical direction on the magnetic tape in view of the transport of the tape and rotation of the scanner. A synchronization detection system (38) determines a first synchronization mark detection time at which a first synchronization mark is read by the first read head from the first track, and a second synchronization mark detection time at which a synchronization mark read by the second read head from the second track. A position error signal generator (100) develops a position error signal (PES) based upon a difference between the first synchronization mark detection time and the second synchronization mark detection time.
    Type: Application
    Filed: January 18, 2001
    Publication date: June 27, 2002
    Inventors: Timothy C. Hughes, David E. Norton
  • Publication number: 20020071195
    Abstract: A scanner (3-85, 8-85, 9-85) for use in a helical scan magnetic transducing apparatus has a periphery upon which plural read tranducing elements (3-82) and plural write transducing elements (3-80) are mounted non-symmetrically. The plural write transducing elements are physically situated on the periphery of the scanner in M number of local groups (3-81), wherein the plural read transducing elements are physically situated on the periphery of the scanner in N number of local moveable groups (3-831, 3-832), and wherein M<N. Each of the moveable groups has a separate actuator (89) for adjusting position of the group.
    Type: Application
    Filed: December 6, 2001
    Publication date: June 13, 2002
    Inventor: Steven L. Magnusson
  • Patent number: 6369966
    Abstract: In order to reproduce the audio signal which has been recorded as an FM audio signal in the slanted tracks of a recording medium in tape form by means of read/write heads arranged on a rotating head drum, it is possible to use PLL circuits which are designed as FM demodulators and in each case form a phase-locked loop with a VCO. FM demodulators of this type generally operate satisfactorily e.g. in video recorders with improved audio signal recording, but there is the risk of the frequency of the VCO of the respective FM demodulator drifting when the read/write head assigned to it leaves the wrap-around region of the recording medium on the head drum and only being able to be synchronized with the FM audio signal when the said head re-enters the recording medium.
    Type: Grant
    Filed: December 3, 1998
    Date of Patent: April 9, 2002
    Assignee: Deutsche Thomson-Brandt GmbH
    Inventor: Hans-Jürgen Kluth
  • Patent number: 6356403
    Abstract: A rotary magnetic head apparatus is provided which can be formed into a small size even if a plurality of reproduction heads are provided.
    Type: Grant
    Filed: April 20, 1998
    Date of Patent: March 12, 2002
    Assignee: Sony Corporation
    Inventors: Tadashi Ozue, Toshio Shirai, Tomohiro Ikegami
  • Patent number: 6304397
    Abstract: A helical scan magnetic recording/reproducing apparatus incorporating an MR head to serve as a reproducing magnetic head is arranged to convert data which is recorded on a magnetic tape into data in the form of DC-free code trains. The magnetic recording/reproducing apparatus is provided with a high-pass filter for attenuating low-frequency components of a reproduced signal detected by the MR head. Moreover, a demodulating circuit is provided which demodulates data in a state before data is converted into the DC-free code trains from the reproduced signal, in which the low-frequency components have been attenuated by said high-pass filter. As a result, noise (thermal asperities) in a low-frequency region caused when the magnetic tape and the MR head are brought into contact with each other is removed so that a reproduced output free from excessive noise is obtained. The high-pass filter is, for example, a rotary transformer mounted on rotational drum.
    Type: Grant
    Filed: August 2, 1999
    Date of Patent: October 16, 2001
    Assignee: Sony Corporation
    Inventors: Tadashi Ozue, Toshio Shirai, Takehiko Saito, Yoshiteru Kamatani, Tomohiro Ikegami
  • Patent number: 6304399
    Abstract: An automatic head switching control method and apparatus detects whether an interval between a head switching point of time and a vertical sync signal is 6.5 horizontal sync signal intervals and repeats processes for altering head switching delay data tD, thereby generating a head switching signal having an appropriate head switching point of time and altering only a head switching point of time for one head during the repeat of the altering process. Accordingly, the velocity change of a drum motor does not occur and a control time is reduced as compared to an envelope detection type controller.
    Type: Grant
    Filed: September 8, 1995
    Date of Patent: October 16, 2001
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Nag-eui Choi
  • Patent number: 6285519
    Abstract: To control operations of an arcuate scanning head assembly, servo signals are written in one or more designated servo regions along a recording tape, for example along one or both edges of the recording area on the tape. To minimize the space occupied by the servo signals, the servo signals are always written with an azimuth that is substantially parallel to the longitudinal axis of the tape. In the preferred embodiment, servo signals aligned with adjacent tracks are written at two different positions within a servo region. As a read head passes over a track and the servo region, the head should overlap the servo signal aligned with that track and a portion of the servo signal aligned with the adjacent track. A control system samples the signal from the read head in a first time window corresponding to passage of the head across a burst aligned with the track and in a second time window corresponding to passage of the head across a burst aligned with the adjacent track.
    Type: Grant
    Filed: July 24, 2000
    Date of Patent: September 4, 2001
    Assignee: Seagate Removable Storage Solutions LLC
    Inventor: Turguy Goker
  • Patent number: 6282042
    Abstract: An adaptive filter 24 for filtering a signal comprising first streams interspersed with second streams (for example the A and B tracks of a signal retrieved from a tape storage device) comprises respective stores for storing initial filter coefficients for each type of stream. The corresponding coefficients are loaded for the beginning of each stream. The stored coefficients for each stream may be a standard set, or they may be from the adaption process of one or more previous streams of that type. The coefficients may be taken part way through the adaption process, in a minimum error portion of the stream.
    Type: Grant
    Filed: September 22, 1997
    Date of Patent: August 28, 2001
    Assignee: Hewlett-Packard Company
    Inventors: Andrew Hana, Christopher Huw Williams, Stephen Paul Langford
  • Patent number: 6278569
    Abstract: A signal recording apparatus and method supplies recording signals to at least a pair of positive and negative azimuth magnetic heads provided on a rotary drum so as to be adjacent to each other in all recording occasions for recording by the magnetic heads when a recording track having a first track width is formed on the magnetic tape, while the apparatus and method supplies recording signals to at least the pair of positive and negative azimuth magnetic heads once in a predetermined number of recording occasions for recording by the recording heads when a recording track having a second track width which is larger than the first track width is formed on the magnetic tape.
    Type: Grant
    Filed: June 7, 1999
    Date of Patent: August 21, 2001
    Assignee: Sony Corporation
    Inventor: Shinichi Fukuda
  • Publication number: 20010013987
    Abstract: At least three heads are mounted on a rotary drum. Between the first and third heads which are located in close proximity to each other and have different azimuth angles, a minute height difference is formed in the rotation shaft direction of the rotary drum. Signals of a plurality of data rates are recorded and reproduced by using the first and second heads or the first and third heads. Two heads having the same azimuth angle are disposed on the rotary drum so as to be opposed each other at a central angle of 180°. In search speed reproduction, search data are reproduced by the two heads. Tracks are divided in the unit of plural tracks so as to form track sets. Search data areas of each track set are disposed at a position of each track which is separated from the edge of a tape by a predetermined distance. In search speed reproduction, the phases of the tracks and the heads are controlled, and all effective data of the search data areas are reproduced by plural scans of the heads.
    Type: Application
    Filed: November 5, 1998
    Publication date: August 16, 2001
    Inventors: YOSHIFUMI YANAGAWA, TADASHI KUNIHIRA, MASAHIRO MOTOSUGI, AKIHIRO TAKEUCHI, MASAAKI KOBAYASHI
  • Publication number: 20010009482
    Abstract: A rotary magnetic head apparatus which can be formed into a smaller size is provided in a case in which signals of a plurality of recording tracks which are recorded on a tape-like information recording medium are reproduced by using a plurality of reproduction heads without depending on the arrangement of the recording tracks in the information recording medium.
    Type: Application
    Filed: March 14, 2001
    Publication date: July 26, 2001
    Applicant: SONY CORPORATION
    Inventors: Tadashi Ozue, Toshio Shirai, Tomohiro Ikegami, Takehiko Saito
  • Patent number: 6263151
    Abstract: In a recording/reproducing apparatus and a reproducing apparatus based on a helical scan system for recording or reproducing a video signal and an audio signal on or from a magnetic tape by use of a magnetic head assembly mounted on a rotary drum, the recording/reproduction of an audio signal in both a standard play mode with a tape speed equal to a standard speed and a long play mode or N-ple play mode with a tape speed N times (N: an integer not smaller than 4) as high as the standard speed is performed by a common audio head. At the time of reproduction in the N-ple play mode, the optimum tracking control is performed by a tracking control system by use of an output of the audio head. At the time of completion of recording in the N-ple play mode, a video signal is supplied with a time prolonged corresponding to the delay of scan of a video head from that of the audio head so that a video track is surely overwritten on an audio track.
    Type: Grant
    Filed: June 4, 1998
    Date of Patent: July 17, 2001
    Assignee: Hitachi, LTD
    Inventors: Hideo Nishijima, Shoji Ohno, Kouji Minabe, Katsuyuki Watanabe
  • Patent number: 6239932
    Abstract: An arrangement for recording servo signals on a magnetic tape has first and second adjoining write heads respectively driven by first and second write signals. Each write signal includes a servo signal and a bias signal, the bias signals being phase displaced periodic signals which result in the magnetic tape being magnetized alternately by the first and second write heads. This provides a sharp transition in the servo signals produced from adjoining servo tracks during read-out.
    Type: Grant
    Filed: October 20, 1998
    Date of Patent: May 29, 2001
    Assignee: OnStream, Inc.
    Inventor: Abraham Hoogendoorn
  • Patent number: 6191907
    Abstract: A head drum for a magnetic tape apparatus includes a stationary lower cylinder and a rotating upper cylinder on which at least one write/read head is securely arranged and interacts with a magnetic tape with an exchange of electromagnetic signals. Also provided are at least one amplifier which rotates together with an upper cylinder and amplifies the signals coming from the write/read head, and a rotating transformer for transferring electrical signals between the stationary lower cylinder and the rotating upper cylinder. Storage means for electrical energy arranged on the rotating upper cylinder is capable of supplying electrical power to all the electronic components rotating together with the upper cylinder. A controller is securely arranged on the rotating upper cylinder for monitoring the charge state of the storage means and controlling the duration of the energy transfer as a function of the charge state.
    Type: Grant
    Filed: May 27, 1998
    Date of Patent: February 20, 2001
    Assignee: Deutsche Thomson-Brandt GmbH
    Inventors: Edgar Wursthorn, Jürgen Kaaden, Klaus Oldermann
  • Patent number: 6175461
    Abstract: A reproduction initial stage amplifier at the rotary side of a rotary head apparatus, prevents an adverse affect of a power transmission signal to a reproduction channel, operates such that a signal from a reproduction head 11 of a rotary head 10 is supplied via a reproduction initial stage amplifier 12 and via windings 22b and 22a of a rotary transformer 20 to a reproduction system 41 of the fixed side. A power signal from a power supply circuit 30 is supplied via windings 21a and 21b of the rotary transformer 20 to a rectifier circuit 15. A rectified output from the rectifier circuit 15 is supplied via a capacitor 16 for power accumulation to a regulator 17, so as to be subjected to voltage stabilization for supply to the reproduction initial stage amplifier 12. During a reproduction operation of the reproduction head 11, a control circuit 42 halts power supply from the power supply circuit 30 and a power accumulated in the capacitor 16 is supplied to the reproduction initial stage amplifier 12.
    Type: Grant
    Filed: June 4, 1998
    Date of Patent: January 16, 2001
    Assignee: Sony Corporation
    Inventors: Shinichi Fukuda, Masahiro Suzuki, Toshihiro Kawakubo, Masanori Okazaki
  • Patent number: 6172831
    Abstract: A digital signal recording method and apparatus for recording digital signals of two channels along tracks on a magnetic tape in a helical pattern by employing at least two pairs of rotary heads mounted on a rotatable drum oppositely to each other and by making use of a read-after-write function, the paired heads being disposed adjacent to each other. The input signal to be recorded is compressed such that the digital signal recording period for each relevant track is shortened by a ratio corresponding to a time for which a write period for one track and a read period for adjacent one overlap each other. The write period and the read period are thus prevented from overlapping. The reproduced signal for the read-after-write function is prevented from being masked by an input signal recording current.
    Type: Grant
    Filed: March 5, 1999
    Date of Patent: January 9, 2001
    Assignee: Aiwa Co., Ltd.
    Inventor: Takumi Usui
  • Patent number: 6157508
    Abstract: A magnetic recording/playback apparatus for recording information to a magnetic tape and playing back the information from the magnetic tape, includes first and second recording heads which are provided on a rotary cylinder and alternately record information to the magnetic tape. First and second playback heads are provided on the rotary cylinder at predetermined positions relative to the first and second recording heads, and alternately play back the information from the magnetic tape. A crosstalk canceling switch device cancels crosstalk at outputs of the first and second playback heads when the apparatus is run in a read-after-write mode, the crosstalk canceling switch device being set in a closed position during the read-and-write mode and interconnecting the output of the first playback head and the output of the second playback head.
    Type: Grant
    Filed: January 14, 1999
    Date of Patent: December 5, 2000
    Assignee: TEAC Corporation
    Inventor: Hiroshi Usami
  • Patent number: 6154332
    Abstract: At least three heads are mounted on a rotary drum. Between the first and third heads which are located in close proximity to each other and have different azimuth angles, an intentionally provided minute height difference is formed in the rotation shaft direction of the rotary drum. Signals of a plurality of data rates are recorded and reproduced by using the first and second heads or the first and third heads. Two heads having the same azimuth angle are disposed on the rotary drum so as to be opposed each other at a central angle of 180.degree.. In search speed reproduction, search data are reproduced by the two heads. Tracks are divided in the unit of plural tracks so as to form track sets. Search data areas of each track set are disposed at a position of each track which is separated from the edge of a tape by a predetermined distance.
    Type: Grant
    Filed: November 5, 1998
    Date of Patent: November 28, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yoshifumi Yanagawa, Tadashi Kunihira, Masahiro Motosugi, Katsumi Gotoh
  • Patent number: 6141166
    Abstract: A magnetic recording device incorporating both a 2-channel recording mode and a multichannel recording mode in one piece of equipment and using recording heads in multiples of two. This magnetic recording device is provided with a head drum, a pair of magnetic recording heads W1+ and W2- of a head width Hw and arranged in mutual proximity and along the rotation direction of the head drum, and a pair of magnetic recording heads W1- and W2+ of a head width Hw/2 and arranged in proximity to the magnetic recording head W2-. These magnetic recording heads W1+, W2-, W1-, W2+ are positioned so that the upper edge of the magnetic recording head W1+, the lower edge of the magnetic recording head W2-, the upper edge of the magnetic recording head W1- and the lower edge of the magnetic recording head W2+ are on the imaginary common line along the rotation direction of the head drum.
    Type: Grant
    Filed: May 27, 1998
    Date of Patent: October 31, 2000
    Assignee: Sony Corporation
    Inventor: Tadashi Ozue
  • Patent number: 6134074
    Abstract: There is provided a reproducing apparatus arranged to reproduce an information signal from a recording medium on which a number of recording tracks are formed in parallel with each other and the information signal is recorded on the recording tracks together with track number information indicative of numbers of the respective tracks, a pilot signal component being multiplexed onto the information signal periodically at intervals of a predetermined number of tracks. When the information signal is to be reproduced from the recording medium, the reproducing apparatus executes tracking control of the reproducing head with respect to a target track, by using the pilot signal component contained in a signal reproduced by a reproducing head. The reproducing apparatus determines the target track according to the track number information separated from the signal reproduced by the reproducing head.
    Type: Grant
    Filed: April 11, 1997
    Date of Patent: October 17, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventor: Shuya Tanaka
  • Patent number: 6130792
    Abstract: To control operations of an arcuate scanning head assembly, servo signals are written in one or more designated servo regions along a recording tape, for example along one or both edges of the recording area on the tape. To minimize the space occupied by the servo signals, the servo signals are always written with an azimuth that is substantially parallel to the longitudinal axis of the tape. In the preferred embodiment, servo signals aligned with adjacent tracks are written at two different positions within a servo region. As a read head passes over a track and the servo region, the head should overlap the servo signal aligned with that track and a portion of the servo signal aligned with the adjacent track. A control system samples the signal from the read head in a first time window corresponding to passage of the head across a burst aligned with the track and in a second time window corresponding to passage of the head across a burst aligned with the adjacent track.
    Type: Grant
    Filed: July 9, 1997
    Date of Patent: October 10, 2000
    Assignee: Seagate Technology, Inc.
    Inventor: Turguy Goker
  • Patent number: 6122432
    Abstract: The present invention provides an information recording apparatus having a rotary drum, plural rotary heads provided on the rotary drum. Each of the plural rotary heads has a rotary transformer to record a recording signal which is obtained by processing a digital information signal to be recorded with a predetermined treatment, on a magnetic tape to form a predetermined track pattern by supplying the recording signal to the plural rotary heads through the rotary transformers. The apparatus further has a signal generating device for generating a signal having an intermediate voltage of an amplitude of the recording signal to be supplied to the rotary heads.
    Type: Grant
    Filed: February 18, 1998
    Date of Patent: September 19, 2000
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Seiji Higurashi, Yoichi Zenno
  • Patent number: 6094319
    Abstract: It is known in the case of digital helical track recording and replay apparatuses for audio, video and general data to be recorded for pilot tones to be interleaved in the data tracks, for tracking. The interleaving can be carried out simultaneously with the data by frequency decoupling (a) or by superimposition (b). The invention is based on the object of providing a helical track recording and replay system which carries out tracking in a simple manner. According to the invention, the ATF signal is obtained in a filter module, which also carries out the rectification of the filtered-out pilot tones. The two DC voltage levels are interrogated and processed in the servo microcontroller, with A/D converters. Coupled to the rotation of the head drum, pulses are produced by the servo system which switch the ATF conditioning over between direct operation and tracking operation, so that evaluation is achieved by the microcontroller during the fast ATF burst phase.
    Type: Grant
    Filed: December 11, 1997
    Date of Patent: July 25, 2000
    Assignee: Deutsche Thomson-Brandt GmbH
    Inventors: Dietmar Braeuer, Juergen Kaaden, Gerhard Reiner
  • Patent number: 6091561
    Abstract: A magnetic recording/reproduction apparatus of an azimuth system for recording/reproducing a digital signal by helical scanning a magnetic tape has an SP mode and an LP mode having recording/reproducing time period N (N is an even number) times that of SP mode. The apparatus includes a pair of magnetic head units with opposite azimuth, disposed in close proximity on a circumferential face of a rotary head cylinder with difference in level therebetween corresponding to a predetermined track pitch t for scanning simultaneously two continuous tracks at that pitch. The cylinder is rotated at the same rotation speed in both SP and LP modes, while the tape travel speed is reduced to 1/N that of SP mode when LP mode is specified. When LP mode is specified, the data amount of a digital signal to be recorded is compressed to 1/N that in SP mode, which are provided to the magnetic heads 2-channel record data, and the data amount of reproduced 2-channel digital signals of is expanded by N.
    Type: Grant
    Filed: May 27, 1994
    Date of Patent: July 18, 2000
    Assignee: Sanyo Electric Co., Ltd.
    Inventor: Toshihide Hamaguchi
  • Patent number: 6081398
    Abstract: A rotary head recording/reproducing apparatus for recording and reproducing digital signals into and from helical tracks on a tape-like recording medium with a rotary head is disclosed. The apparatus comprises: a recording head section composed of first and second recording heads having different azimuth angles are closely located on a rotary drum; a first reproducing head section provided at 90.degree. to the recording head section, the first reproducing head section being composed of first and second reproducing heads closely located, the first and second reproducing heads having azimuth angles corresponding to the first and second recording heads of the recording head section, respectively; and a second reproducing head section provided at 180.degree.
    Type: Grant
    Filed: April 3, 1997
    Date of Patent: June 27, 2000
    Assignee: Sony Corporation
    Inventor: Tadashi Ozue
  • Patent number: 6031681
    Abstract: In an arcuate scanner, a read head senses passage over a reference stripe recorded on a moving recording tape. Detection and logic circuitry respond to the read head signal to detect the reference stripe and determine an angular position of the read head with respect to an index associated with the arcuate scanner head assembly. Timing operations of the arcuate scanner and alignment of the arcuate scanner head assembly with regard to an information recording region on the tape are controlled in reference to the detection of the reference stripe.
    Type: Grant
    Filed: May 1, 1998
    Date of Patent: February 29, 2000
    Assignee: Seagate Technology, Inc.
    Inventors: Turguy Goker, William Buchan
  • Patent number: 6021014
    Abstract: A head switching signal generation apparatus for a VCR includes a pulse signal generator for generating a first pulse signal having the same phase and period of time as a head drum pulse signal in response to the head drum pulse signal, an envelope detector for detecting an envelope signal from a signal read out from a video tape and generating a second pulse signal having the same phase and period of time as the detected envelope signal, and a controller for generating a head switching signal whose pulse level is altered at an actual head switching point of time, based on the received first and second pulse signals. An accurate head switching signal can be generated even when a vertical sync signal is not detected from a video tape having a recording format for recording a vertical sync signal, as well as a recording format by which a vertical sync signal is not recorded on a video tape.
    Type: Grant
    Filed: July 3, 1996
    Date of Patent: February 1, 2000
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Gan-soo Seoung
  • Patent number: 6014278
    Abstract: At least three heads are mounted on a rotary drum. Between the first and third heads which are located in close proximity to each other and have different azimuth angles, a minute height difference is formed in the rotation shaft direction of the rotary drum. Signals of a plurality of data rates are recorded and reproduced by using the first and second heads or the first and third heads. Two heads having the same azimuth angle are disposed on the rotary drum so as to be opposed each other at a central angle of 180.degree.. In search speed reproduction, search data are reproduced by the two heads. Tracks are divided in the unit of plural tracks so as to form track sets. Search data areas of each track set are disposed at a position of each track which is separated from the edge of a tape by a predetermined distance. In search speed reproduction, the phases of the tracks and the heads are controlled, and all effective data of the search data areas are reproduced by plural scans of the heads.
    Type: Grant
    Filed: March 7, 1996
    Date of Patent: January 11, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Katsumi Gotoh, Kenji Matsuura, Masafumi Shimotashiro
  • Patent number: 6011665
    Abstract: A device for recording an information signal on a magnetic tape by using a helical scan include a rotary drum, a plurality of types of magnetic heads including at least one magnetic head of each of said types provided on the rotary drum for recording a corresponding type of the information signal, and switching units which switch said at least one magnetic head between a recording of the information signal and an erasing of the information signal. During rotation of the rotary drum, one type of said at least one magnetic head erases the information signal prerecorded on the magnetic tape before another type of said at least one magnetic head records a corresponding type of the information signal on the magnetic tape.
    Type: Grant
    Filed: October 28, 1997
    Date of Patent: January 4, 2000
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Takeo Ohishi, Seiji Higurashi
  • Patent number: 5995311
    Abstract: A switch device switchable as a first channel (200) to an inactive state and a dummy channel (201) to an active state the switching device switches the dummy channel to an inactive state while switching a second channel 300 to an active state.
    Type: Grant
    Filed: April 30, 1997
    Date of Patent: November 30, 1999
    Assignee: Texas Instruments Incorporated
    Inventor: Hiro Kuwano
  • Patent number: 5991109
    Abstract: A magnetic recording and reproducing apparatus includes a reading and writing head for writing data on data tracks formed on a recording tape and reading the data therefrom to produce a first reproduction data. A simultaneous reproducing head is provided for reading a second production data from the data track just being written or read by the reading and writing head. A delay unit delays the first signal by a predetermined phase difference factor to arrange the first and second reproduction data on the same time base. A determiner is also provided for selecting either of said first and second reproduction signals whose signal quality is better than the other.
    Type: Grant
    Filed: November 18, 1996
    Date of Patent: November 23, 1999
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masatoshi Taniguchi, Toshiyuki Kohri, Keiichi Ishida
  • Patent number: 5986829
    Abstract: A high speed digital recording and reproducing apparatus fo duplicating of a tape at a speed N-times faster than a speed for a normal speed duplication. The apparatus includes a recording head drum and a reproduction head drum having N-times a diameter and 1/N-times a surrounding angle compared with those of the normal speed duplication, 2N reproduction heads and recording heads which are disposed on the head drums, respectively, a signal processor for processing signals transmitted from the reproduction heads to match the high-speed duplication and supplying the processed signals to said recording heads, and a controller for transferring the source tape and target tape at N-times the normal speed, and controlling the head drums to rotate at the rate which meets the condition: N.times.(drum diameter at the normal speed)/(drum diameter at N-times high-speed duplication).times.(the number of rotation in case of the normal speed).
    Type: Grant
    Filed: November 25, 1996
    Date of Patent: November 16, 1999
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Kyung-Hwan Choi
  • Patent number: 5966260
    Abstract: A recording and reproducing apparatus for recording and reproducing a data signal on and from a magnetic tape includes a rotary head drum, first and second magnetic heads, third and fourth magnetic heads, a data processor, a data signal decoder, and controller. The magnetic tape is wrapped around the rotary head drum slanted at a predetermined angle. The first and second magnetic heads are provided on the rotary head drum at positions apart from each other by a predetermined rotational angle and have a first azimuth angle. The third and fourth magnetic heads are provided on the rotary head drum at positions apart from each other by a predetermined rotational angle and have a second azimuth angle different from the first azimuth angle. The data processor adds address data to each recording unit of a data signal and outputs the data signal as a recording signal.
    Type: Grant
    Filed: August 11, 1997
    Date of Patent: October 12, 1999
    Assignee: Sony Corporation
    Inventors: Katsumi Ikeda, Takuji Himeno, Takashi Katoku, Takanobu Sano
  • Patent number: 5963384
    Abstract: A signal recording device is provided for transmitting recording data signals via a rotary transformer to a rotary drum having a rotary head for recording data so that control data may be transmitted in a shorter time period and resolution along the time axis may be improved. A 1-bit start bit SB and 2-bit mode setting bits PD are followed by 3-bit group bits GP and 3-bit channel bits CL for a single bit mode, by 3-bit group bits GP and an 8-bit bit patterns BP for a multi-bit mode and by a 4-bit channel number DAN and 8-bit data DAD for D/A data. An even parity PE is appended for each of the respective modes. A continuation flag CF is further appended for the single-bit mode and the multi-bit mode.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: October 5, 1999
    Assignee: Sony Corporation
    Inventors: Minoru Kawahara, Hitoshi Tsujii, Kazuo Tomita
  • Patent number: 5960398
    Abstract: A copyright information embedding system is provided which is designed to embed information for copyright protection into digital audio signals without deterioration of analog audio signals reproduced. The copyright information embedding system includes an A/D converter, a modulator, a level detector, and a copyright data embedding circuit. The A/D converter converts an analog audio signal into a digital signal. The modulator modulates a copyright data signal for the digital signal using spectrum spread. The level detector detects a variation in level of the digital signal. The copyright data embedding circuit divides the copyright data signal into several codes and embeds them into the digital signal each time the variation in level of the digital signal shows a preselected variation such as a rapid rise or drop.
    Type: Grant
    Filed: July 28, 1997
    Date of Patent: September 28, 1999
    Assignee: Wictor Company of Japan, Ltd.
    Inventors: Norihiko Fuchigami, Shoji Ueno, Yoshiaki Tanaka
  • Patent number: 5953172
    Abstract: In a digital VTR to which this invention is applied, recording heads 51a, 51b, reproduction heads 52a, 52b and an erase head 53 are disposed on a rotary drum 50 so that the recording heads 51a, 51b and the erase head 53 do not scan tracks for a time period during which the reproduction heads 52a, 52b are scanning tracking areas 2 and speech areas 3. In the case where, e.g., speech signal of channel #1 is insert-recorded, an approach is employed to separate, at a reproduction signal processing circuit 67, speech signal of channel #2 of interleaved speech signals reproduced by the reproduction heads 52a, 52b to deliver it to a recording signal processing circuit 46 through a selector switch 45b. Further, the speech signal of the channel #2 and new speech signal of the channel #1 delivered through a terminal 42a are interleaved by the recording signal processing circuit 46 to record such interleaved signals into the speech areas 3 by the recording heads 51a, 51b.
    Type: Grant
    Filed: February 10, 1997
    Date of Patent: September 14, 1999
    Assignee: Sony Corporation
    Inventors: Kenji Nakamura, Isao Tsutsumi
  • Patent number: 5912780
    Abstract: A magnetic recording and reproducing apparatus has a rotary magnetic head mechanism having at least a first rotary magnetic head with a magnetic gap set to a azimuth angle less than 90 degrees in a clockwise direction with respect to a width direction of recorded traces and a second rotary magnetic head with a magnetic gap set to a azimuth angle less than 90 degrees in a counterclockwise direction with respect to the width direction. The traces are formed on a magnetic tape moving in a forward direction at a speed in accordance with a rotational locus of the heads moving and obliquely crossing a travel direction of the tape. The first output signals obtained by the first head are selected in the case where a rotational locus surface of the heads changes in a reproduction operation within an angular range less than 180 degrees in a clockwise direction with respect to the traces formed on the tape.
    Type: Grant
    Filed: January 28, 1997
    Date of Patent: June 15, 1999
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Yasuaki Yamada, Takeo Ohishi