Abstract: A method and apparatus for constraining lateral motion of a tape streaming in a first direction across the transducing face of a magnetic head by provision of at least one arcuate portion of the tape travel path. This arcuate portion is defined by one set of at least three tape guide rollers on a first side of the head. A second set of at least three tape guide rollers may be provided to define a second arcuate portion of the tape guide path on a second side of the head for use when the tape is streaming in a second direction opposite to the first direction across the transducing face of the head.

Abstract: A disc drive unit in which a controller detects the storage capacity of the disc cartridge during loading into the drive by interrogating switches which are actuated by capacity indication markers on the disc cartridge.

Abstract: A magnetic head has a magnetic core comprising a first half core on which a thin magnetic metal film is deposited and a second half core which is opposed to the first half core across a magnetic gap. The film thickness of the thin magnetic metal film of the first half core continuously varies at about a constant rate within a portion thereof adjacent to the effective portion of the magnetic gap.

Abstract: A magnetic tape cartridge which is capable of permitting tape guides and a magnetic tape to exhibit resistance to wear and resistance to scraping sufficient to prevent the wearing of the tape guides and ensure the safe traveling of the magnetic tape over a long period of time, respectively. A polyester film forming a base of the magnetic tape contains a basic filler which absorbs a basic indicator bromothymol blue thereon while keeping it blue and a pair of the tape guides contacted with the polyester film are formed of ultra-high-molecular-weight polyolefin.

Abstract: A thin-film magnetic head comprising four or more conductive coil layers each wound spirally and alternately piled up so as to form a lamination structure. The conductive coil layers are divided into first and second groups so that the total number of turns of the conductive coil layers in the first group becomes equal to the total number of turns of the conductive layers in the second group. The conductive coil layers in the first group are coupled in series to each other and the conductive coil layers in the second group are also coupled in series to each other, the first and second groups being coupled in series to each other and a center tap being provided between the first and second groups.

Abstract: A cleaning device for cleaning a rotary magnetic head of a magnetic recording and reproducing device includes a cleaning member which is movable into and out of contact with the rotating magnetic head. The cleaning device is activated through the operation of a manually operable button and under the control of an electronic control device. The cleaning member is automatically brought into contact with the magnetic head to clean the same. The operation of the cleaning device is carried out in association with an operation of a tape loading mechanism of the magnetic recording and reproducing device. The vertical position of the cleaning member is changed when it is contacted with the magnetic head, so that the portion of the cleaning member to be contacted with the magnetic head is changed.

Abstract: A magnetic tape cleaner comprising a back-glued pad of cleaning cotton, and a resilient fastener means to secure said back-glued pad of cleaning cotton to the casing of a video tape inside the protective cover thereof for cleaning the magnetic tape, wherein said resilient fastener means has a first unitary hooked member hooked in the infrared projecting hole in the casing of said video tape, a second unitary hooked member hooked in the gap defined in the casing of said video tape at the left side between the protective cover thereof, and a rectangular hole disposed in alignment with said infrared projecting hole for the passing therethrough of the infrared light from a video tape player. The cleaning pad is resiliently forced to move backwards by the magnetic tape of the video tape when the video tape is loaded in a video tape player to play, so that friction force between the magnetic tape and the cleaning pad is greatly reduced during cleaning operation.

Abstract: In order to improve the sensitivity of the head when reading, without excessively reducing its efficiency when writing, the magnetic circuit used is left open. The reading flux then re-closes, essentially across the magnetoresistant element (MR).

Abstract: A method and apparatus are provided for measuring flying height changes of a transducer head relative to a disk surface of a rotating disk in a disk file. A predetermined pattern is written on at least one predetermined region of the disk file. The predetermined region is normally not rewritten during operation of the disk file. At least one readback signal is sensed from at least one predetermined region of the disk surface. A plurality of sample values are identified corresponding to each readback signal. A change in the flying height is calculated utilizing the identified sample values. A frequency equalization number K can be utilized to calculate the magnitude and sign of the flying height change. Alternatively, real-time digital analysis of a predetermined pattern written on at least one predetermined region of the disk surface can be utilized to calculate the magnitude and sign of the flying height change.

Abstract: A magnetic reproducing head amplifier includes a differential amplifier referred to as one of these three types: a balanced input type, a balanced output type, or a balanced input/output type. The amplifier has at least one positive feedback circuit for passing a positive feedback current to the differential amplifier, and at least one negative feedback circuits for passing a negative feedback current to the differential amplifier and is configured so that a positive feedback and a negative feedback are simultaneously performed by the positive feedback circuit as well as the negative feedback circuit. A resonance peak characteristic at the input part of the differential amplifier is dumped by the negative feedback current, and therefore a frequency characteristic as well as a group delay characteristic of the output of the differential amplifier becomes flattened.

Abstract: An integrated read/write transducer and flexure support structure is provided for use with rotating magnetic media such as a hard disc drive. The integrated structure includes at least one magnetic pole structure integral with a unitary sheet of flexible magnetic material from which the flexure support is formed. A second magnetic pole is supported on the structure, together with conductive coils, to form an electromagnetic transducer. The integrated structure includes an air-bearing surface mounted for parallel motion with respect to adjacent magnetic media. A pattern of positive-pressure air-bearing rails and negative-pressure recesses provides an aerodynamically stable configuration designed to fly at a height of approximately 5 microinches above the moving magnetic media. Conductors and interconnect pads are provided on the magnetic sheet material substrate.

Abstract: A magnetic tape recording and/or reproducing apparatus comprises a rotary cylinder having a plurality of magnetic transducer heads on a cylindrical surface thereof and rotatable about an axis tilted to the vertical for producing obliquely scanned paths on a magnetic tape. A first tape loading mechanism includes a first post movable along a first guide groove extending from a first inital position in which it engages with a tape from a cassette to a first terminal position adjacent the rotary cylinder. A second tape loading mechnism includes a second post movable along a second guide groove extending from a second initial position in which it engages with the tape to a second terminal position adjacent the rotary cylinder. The first and second tape loading mechanisms are driven to that the first and second posts move from the initial positions to the terminal positions to cause the tape to be pulled out of the cassette and form an arc of a predetermined angle on the cylindrical wall of the rotary cylinder.

Abstract: A video tape recording prohibition setting method is disclosed, in which only the regions of the video tape other than the prohibited region can be recorded through the utilization of the count values for the indicator by means of microcomputer control. Through the use of the method of the present invention, the troublesome task of manually switching over the system mode by the user can be removed when making some desired portion of the tape saved from being erased, and economic use of the tape achieved.

Abstract: A data reproducing circuit, and more particularly, a data reproducing circuit which records magnetization reversal patterns corresponding to a written digital signal onto a magnetic recording medium, and converts a received analog signal from the magnetic recording medium into a digital signal. The present invention has a pre-shift circuit to perform peak shift compensation in the recording process, an equalizer to perform peak shift compensation in the reproducing process, and a digital data reproducing circuit to reproduce data by differentiating the equalized signal received from the equalizer and generating a window signal. The equalizer means contains the first equalizer which compensates the peak position shifting in the received analog signal from the magnetic head and outputs the equalized signal used for differentiation, and the second equalizer which corrects the peak level variation of the analog signal and outputs the equalized signal used for window signal generation.

Abstract: The present invention is an apparatus and method for an improved actuator arm assembly in a disc drive. The improvement arises by casting a steel sleeve into the actuator arm to define a pivot bore. A steel bearing and shaft assembly cooperates with the pivot bore to enable the actuator arm to rotate about the shaft. This all steel arrangement minimizes the bearing preload necessary to create a stable actuator arm assembly having a minimum amount of friction in the bearing system.

Abstract: A tape cassette is provided which is suitable for digital recording and playback which require high reliability, is interchangeable in terms of dimensions and shape with conventional compact cassettes, and is provided with a shutter member which selectively opens and closes insertion windows for the magnetic head and pinch rollers and is normally urged in the closing direction, to thereby prevent dust, etc. from entering. Moreover, since the shutter member is arranged to slide in the longitudinal direction, there is no increase in the volume of the tape cassette, even during opening or closing of the shutter member.

Abstract: In a tape recording and/or reproducing apparatus having a head drum and a plurality of rotary elements including at least rotary heads associated with the head drum for recording and/or reproducing information signals on a magnetic tape wrapped around the head drum, a capstan for transporting the magnetic tape at a constant speed, and supply and take-up reel bases for engaging a pair of reels around which the magnetic tape is wound in a tape cassette and for driving the respective reels; a single motor is directly coupled to one of the rotary elements and drives the other rotary elements through a non-slip mechanical transmission for synchronously rotating at least the rotary heads, the capstan and the supply and take-up reel bases.

Abstract: A magnetic head carriage device which comprises a head carriage body provided on a magnetic disk drive apparatus slidably in a radial direction of a magnetic disk and in parallel to a guiding axis, an upper arm provided on the head carriage body to have an upper magnetic head on its lower surface, and a plurality of bearing members each having an annular bearing portion and a mounting arm, the annular bearing portion into which a guiding shaft is inserted along the guiding axis, the mounting arm portion extending outwardly from the annular bearing portion, the mounting arm portion of each of the bearing members being fixed to the head carriage body such that the annular bearing portions are located laterally from the head carriage body. The magnetic disk drive apparatus employing this magnetic head carriage device can be constructed to suit the demands in the field, especially one having an overall thickness smaller than that of a conventional magnetic disk drive apparatus.

Abstract: A magnetic disk drive includes a spindle for rotating a plurality of magnetic disks and a lock mechanism for preventing the spindle from rotating when the magnetic disk drive is not operated. A toothed disk is provided on an axial end of the spindle, and a movable lock arm engageable to teeth of the toothed disk is provided. The lock arm is driven to lock the rotation of the spindle by a solenoid which is energized after a predetermined period of time has elapsed after the electric power of the disk drive is turned off, so that the lock mechanism locks the spindle after the rotation of the spindle and magnetic disks completely stop.

Abstract: A tape transport which is sized to fit within an 8 inch form factor or footprint, to accommodate prevailing mini/micro computer applications, and including operative components which are capable of automatically receiving IBM Corporation's 3480-type tape cartridge and the web of tape which it contains for appropriate introduction to the transport for presentation to a high performance magnetic recording head. This permits a use of the 3480 tape cartridge in a transport apparatus which is capable of fitting within an 8 inch form factor or footprint, and which is therfore acceptable for use in connection with many mini/micro computer applications, yet which is capable of providing high performance (parallel track, high transfer rate) storage and retrieval due to its compatability (and interchangeability) with the format used by the IBM Corporation in connection with its 3480 tape cartridge.