Sony Corporation

Toshio Shirai

Tadashi Ozue

Tomohiro Ikegami

Yoshiteru Kamatani

Takehiko Saito

Toshiharu Kobayashi

Makoto Ando

Shinichi Fukuda

Takumi Okaue

Takeshi Hori

Ichiro Hashimoto

Keisuke Unno

Yoshiharu Higano

Toru Naganuma

A rotary drum includes a plurality of reproducing heads each having a plus azimuth angle (+azimuth angle), which heads are collectively arranged at a location in the circumferential direction of the rotary drum in such a manner as to be in close proximity to each other, to be taken as a +azimuth reproducing head group, and a plurality of reproducing heads each having a minus azimuth angle (&#x2212;azimuth angle), which heads are collectively arranged at a location in the circumferential direction of the rotary drum in such a manner as to be in close proximity to each other, to be taken as a &#x2212;azimuth reproducing head group, wherein the +azimuth reproducing head group and the &#x2212;azimuth reproducing head group are spaced from each other in the circumferential direction of the rotary drum. With this rotary drum, signals can be certainly reproduced from recording tracks with narrowed widths by using the multiple reproducing heads arranged on the rotary drum.

Rotary drum and magnetic reproducing apparatus or magnetic recording and reproducing apparatus using the same

A rotary magnetic head apparatus which can be formed into a smaller size 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. The rotary magnetic head apparatus includes a rotary drum, a fixed drum, a reproduction signal selection device, a rotor reproduction signal wiring section, and a stator reproduction signal wiring section.

Rotary magnetic head apparatus for performing reproduction operations using a plurality of reproduction heads without depending on the arrangement of the recording tracks

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&deg; 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&deg; of central angle and a second mode is created by the two recording heads at the same position in the circumferential position.

Rotary drum and magnetic tape recording/reproducing apparatus using the same

A magneto-resistive effect type magnetic head ( ) has a head width Wh greater than the track width Wt of a magnetic tape ( ), as measured in the width direction of the tape ( ). The head ( ) has a magneto-resistive effect element, which has a magnetism-detecting section arranged at the prescribed azimuth angle. A signal reproduced from the magnetic tape as the head ( ) is moved while off-tracked in the widthwise direction Wh of the recording track T . The signal has a specific characteristic that falls within a predetermined range for a reference value, provided that it has been generated from the magnetism the head ( ) has detected over its effective width We.

Magneto-resistive effect type magnetic head and magnetic tape apparatus

A rotating drum assembly, and a magnetic recording/reproducing apparatus including the rotating drum assembly, are provided. The rotating drum assembly comprises a cylindrical rotating drum; a magneto-resistive head installed on the rotating drum to project at least a part thereof from the outer surface of the rotating drum; and a tape-contact piece installed on the rotating drum so as to project from the outer surface of the rotating drum and to be in contact with the surface of a magnetic tape; the tape-contact piece being formed to have a larger tape-contact width than that of the magneto-resistive head and disposed to be in earlier contact with the magnetic tape than the magneto-resistive head.

Rotating drum assembly and magnetic recording/reproducing apparatus having a tape-contact piece

A rotary magnetic head unit has a non-contact type transmission device capable of reliably performing non-contact transmission both in signal and power supply systems and designed so as to be smaller in size. The non-contact type transmission device is formed of a rotating member and a fixed member each having a power supply wiring section for transmitting a power supply, a signal wiring section for transmitting a signal, and a crosstalk prevention section positioned between the power supply wiring section and the signal wiring section to prevent crosstalk between these sections. If a reproducing head formed of a magnetoresistive element is used by being supplied with a bias current from the power supply transmitted by the power supply wiring sections of the rotary and fixed members, the rotary magnetic head unit uses bias current control means section to change the bias current supplied to the reproducing head according to the amount of wear of the recording head during reproduction from signals from magnetic tapes.

Non-contact type transmission device and rotary magnetic head unit having the non-contact type transmission device and a bias current control section

A magnetic signal reproducing method and apparatus of the helical scan system employing an MR head. The apparatus includes a substantially cylindrically-shaped rotary drum, an inductive magnetic head loaded on the rotary drum, a magneto-resistive effect magnetic head having an amount of protrusion from the rotary drum smaller than that of the inductive magnetic head, a tape sort detection unit, and a tape tension control unit. If information signals are reproduced by the inductive magnetic head, the tape tension of the magnetic tape is decreased by the tape tension control unit and, if information signals are reproduced by the magneto-resistive effect magnetic head, the tape tension of the magnetic tape is increased by the tape tension control unit.

Magnetic signal reproducing method and apparatus

A rotary drum device and a helical scan magnetic recording/reproducing apparatus employing an MR head as a playback magnetic head. The rotary drum device and the helical scan magnetic recording/reproducing apparatus each include a cylindrically-shaped rotary drum, an inductive magnetic head loaded on the rotary drum so that its portion is protruded from the outer periphery of the rotary drum and a magneto-resistive effect magnetic head loaded on the rotary drum so that its portion is protruded from the outer periphery of the rotary drum. An amount of protrusion from the outer periphery of the rotary drum of the magneto-resistive effect magnetic head is smaller than an amount of protrusion from the outer periphery of the rotary drum of the inductive magnetic head.

Rotary drum device and magnetic recording/reproducing apparatus having a more protruding inductive magnetic head relative to magnetoresistive head

A rotary magnetic head apparatus is provided which can be formed into a small size even if a plurality of reproduction heads are provided. The rotary magnetic head apparatus includes a rotary drum having a rotor of a transmission apparatus and a plurality of reproduction heads, a fixed drum having a stator of the transmission apparatus and a plurality of reproduction heads, a reproduction signal selection device for selecting a reproduction signal of an information recording medium, which signal is obtained by each of the reproduction heads and for arranging the reproduction signal in sequence, a rotor reproduction signal wiring section which is disposed in the rotor and to which is supplied the reproduction signal of each of the reproduction heads, which reproduction signal is sent from the reproduction signal selection device, and a stator reproduction signal wiring section, which is disposed in the stator, for receiving the reproduction signal from the rotor reproduction signal wiring section without contact.

Rotary magnetic head apparatus having reproduction signal wiring, power-supply wiring and recording signal wiring sections in a rotor and a stator arranged in a predetermined manner

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.

Magnetic recording/reproducing apparatus with rotary drum with magnetoresistance head for transducing DC-free code signals

A magnetic signal reproducing apparatus which can lessen fluctuation of reproduced outputs in reproducing magnetic signals recorded in a magnetic tape by a magneto-resistance effect type magnetic head even if a magnetic tape sliding face of the magneto-resistance effect type magnetic head is abraded. A current value of a sense current when a voltage fluctuation level of the sense current caused when a magnetic field in the normal direction is applied to a magneto-resistance effect element of the magneto-resistance effect type magnetic head is equal with a voltage fluctuation level of the sense current caused when a magnetic field in the opposite direction is applied thereto is set to a predetermined value I,Then, the current value of the sense current supplied to the magneto-resistance effect element of the magneto-resistance effect type magnetic head is set to be greater than I,in reproducing the magnetic signals recorded in the magnetic tape.

Magnetic signal reproducing method and apparatus using magneto-resistive effect element with increased sense current

A rotary magnetic head unit has a non-contact type transmission device capable of reliably performing non-contact transmission both in signal and power supply systems and designed so as to be smaller in size. The non-contact type transmission device is formed of a rotating member and a fixed member each having a power supply wiring section for transmitting a power supply, a signal wiring section for transmitting a signal, and a crosstalk prevention section positioned between the power supply wiring section and the signal wiring section to prevent crosstalk between these sections. If a reproducing head formed of a magnetoresistive element is used by being supplied with a bias current from the power supply transmitted by the power supply wiring sections of the rotary and fixed members, the rotary magnetic head unit uses bias current control means to change the bias current supplied to the reproducing head according to the amount of wear of the recording head during reproduction from signals from magnetic tapes.

Non-contact type transmission device and rotary magnetic head unit having the non-contact type transmission device

A magnetic recording/reproducing apparatus of the helical scan system employing a MR head as a reproducing magnetic head. The magnetic recording/reproducing apparatus includes a MR head,and a rotary drum carrying the MR head,In reproducing signals from the magnetic tape,in accordance with the helical scan system, a magnetic tape,having a large number of projections,on the tape surface and containing an electrically conductive material in its magnetic layer, is used as a recording medium.

Magnetic recording/reproducing apparatus and magnetic tape

A magnetic tape transfer printing apparatus including a drum mounted for rotation. A master magnetic tape having information recorded thereon is held in contact with a slave magnetic tape on a portion of the circumferential surface of the drum. A magnetic transfer bias field is applied to transfer the information from the master magnetic tape onto the slave magnetic tape. The drum contains a high-permeability magnetic material at least in the circumferential surface. This is effective to decrease the lateral component of the bias magnetic field and increase the vertical component of the bias magnetic field, thereby minimizing the degree of demagnetization of the master magnetic tape during the transfer printing process.

Magnetic tape transfer printing apparatus

A high-speed contact printing system is provided with a read head which picks up control signals recorded on a slave tape and a recording head which, after a given delay following reproduction of the control signal by the read head, writes the refined control signal back onto the corresponding section of the slave tape. The recording head is so arranged relative to the read head as to face the proper recording track on which the control signal is to be recorded after the given delay. For application to both .beta. and VHS systems, the distance H between the read head and the recording head is determined according to the following formula:

Growing community of inventors

Kanagawa, Japan

Toshio Shirai