Abstract: An apparatus having a magnetic head assembly including a plurality of arms each arm having a magnetic head fixed to a nose portion thereof and a magnetic disk unit having a plurality of magnetic disks mounted on a rotating shaft. The spacing between adjacent magnetic disks being set at a value corresponding to the thicknesses of the magnetic heads fixed to two of the arms, plus the thickness of the two arms, plus a rotating gap of the magnetic heads, plus a space of 0.1 mm or less. Further included is a disk height measuring device and a head measuring device for measuring the heights of the disks and the magnetic heads. An expansion device expands the spacing between the adjacent arms. The spacing between the adjacent arms being expanded an appropriate amount to provide optimal operation of the magnetic disk apparatus.

Abstract: An FM signal which is partly missing zero crossing points is supplied to an input terminal, to which a second polarity discriminating circuit and a lower side band suppressing circuit followed by a first polarity discriminating circuit are coupled together. A pulse extracting circuit receives the outputs of the first polarity discriminating circuit and a second polarity discriminating circuit to produce pulses corresponding only to portions of the FM signal at which the zero crossing points are absent. The pulses thus obtained are subsequently combined in a waveform reforming circuits with the FM signal from the input terminal, thereby permitting the FM signal to regain the zero crossing points.

Abstract: In a magnetic disk apparatus according to the present invention, a slider has a sliding surface and a reflecting surface. The height of the reflecting surface from the magnetic disk is greater than that of the sliding surface from the disk, when the slider flies above the disk, so that there exists a minute difference in level between the sliding surface and the reflecting surface. The flying height of the sliding surface of the slider from the magnetic disk is measured. When the magnetic disk is rotated, the slider flies from the disk. In this state, a reference flying height, i.e., the flying height of the reflecting surface from the magnetic disk is measured by the optical interference process. Then, the minute difference is substracted from the measured reference flying height to obtain the flying height of the sliding surface of the slider from the magnetic disk. According to the invention, even if the minimum flying height of the sliding surface of the slider is shorter than 0.

Abstract: An iron-aluminum-silicon (Fe-Al-Si) series magnetic alloy magnetic head is described. The magnetic head is filled between front gap forming surfaces (the front gap facing a magnetic tape) of a pair of Fe-Al-Si core pieces with non-magnetic ceramic films formed on the respective front gap forming surfaces and a glass film formed therebetween, and between rear gap forming surfaces for junction with an Ag-Cu-In series alloy film.

Abstract: A magnetic disc cartridge has a lifter supported by a wall of the disc cartridge. The lifter has a riser for pressing a liner or liners against a disc sheet rotatably supported in the disc cartridge. The pressing force B/A of the riser is at least 0.6, where A equals the pressing force of the riser which is measured at ordinary temperature and humidity during an initial period when the lifter is combined with the cartridge, and B is the pressing force of the riser which is measured at ordinary temperature and humidity after the cartridge has been held at a temperature of 60.degree. C. and a humidity of 80% for seventy-two hours.

Abstract: A cassette changer for automatically inserting and discharging (changing) tape cassettes for a magnetic recording-reproduction apparatus of the front loading type, such as a video tape recorder. The cassette changer has a cassette discharge path for discharging a cassette along a slope when the cassette is ejected from the cassette inlet-outlet opening of the apparatus after recording or reproduction, a cassette insertion path intersecting the discharge path in front of the opening for guiding a new cassette along a horizontal plane into the opening for recording or reproduction, and a separator disposed at the intersection for alternately opening the paths for the discharge and insertion of the cassette.

Abstract: A magnetoresistance type magnetic head, in which a magnetoresistance film is disposed through an insulating film between two soft magnetic bodies, and a signal leadout conductor for the magnetoresistance film is disposed in the insulating film so that its surface is at the same level as that of the insulating film, thereby providing a high-performance magnetoresistance type magnetic head, in which the gap length is small and the resistance of the signal leadout conductor portion is small.

Abstract: A coupling device for the transmission of an axial movement from a lift generator to a rotatable, axially movable body, composed of: a component creating a pressure-transmitting contact between the lift generator and the body; and a device including a magnet producing a magnetic field which creates a magnetic attraction force between the lift generator and the body.

Abstract: A magnetic tape cassette having two symmetrical sides and which includes a cassette body having shaft-receiving holes formed respectively in right and left walls of the cassette body in such a manner that the holes are elongated in the front-to-rear direction of the cassette body. A substantially U-shaped guard panel is provided having rotary shafts on both ends engaged with the elongated holes so that the guard panel can be swung about the rotary shafts. A spring is connected between the cassette body and the guard panel to urge the latter to close the opening formed in the front wall of the cassette body.

Abstract: A magnetic disk storage device capable of avoiding the occurrence of vibration of magnetic disks and off-track of magnetic heads with respect to the magnetic disks, including an inner shroud enclosing a disk assembly composed of a multiplicity of magnetic disks stacked in superposed relation with spacers being interposed therebetween and formed at its outer peripheral wall with first ports for inserting access arms therethrough and at its top above a spindle supporting the disk assembly with a second port, a cylindrical filter for removing dust from air flowing through the second port of the inner shroud into the interior thereof, and a dust cover enclosing the inner shroud, actuators and filter. The provision of the inner shroud is conductive to prevention of development of turbulent air flow in the vicinity of the magnetic disks.

Abstract: A driving mechanism for magnetic hard disc memories includes an isolated space for maximum cleanness from the remainder of the apparatus, a driving motor mounted within the apparatus and having a stator and a rotor, the motor when energized having parts producing magnetic flux, a hub extending into the space of maximum cleanness for receiving therein at least one magnetic hard memory disc, a connection between the motor and the hub for driving the hub, and a magnetic flux shield located between the parts producing the magnetic flux and the space of maximum cleanness.

Abstract: A memory apparatus suitable for storing data for a high resolution bit mapped display includes large capacity (e.g. 64-k) semiconductor random access memory circuits in which to reduce the effective access time the circuits are operated and addressed in a repeating cycle including in succession reading from two or more addresses in sequence having the same row address component (i.e. in page mode), for example for the display, and writing into or reading from a randomly selected address.

Abstract: Improved disk drive equipment is illustrated, being characterized by improved partitioning means for partitioning a stack of flexible magnetic recording disks axially (end-wise).

Abstract: A tape recorder comprises transfer mechanism which is operatively connected to a power switch and transfers a head support lever to a position where a magnetic head is in contact with a tape upon shifting of the power switch to its "ON" position. The power switch has "ON", "OFF", and "EJECT" positions in order, and, when set in the "EJECT" position, rocks a rockable eject lever for cassette ejection.

Abstract: Techniques and associated apparatus for a magnetic disk transducing system adapted to record along spiral tracks in a Herringbone pattern, using a pair of orthogonal skew gaps, operating in tandem.

Abstract: An improved "floppy cartridge" is described comprising a jacket especially adapted for containing a pack of flexible disks, this jacket accommodating convenient insertion and withdrawal of the disk pack, while also permitting rotation and associated partitioning of the pack, as well as head-insertion and transducing on a selected disk--all with the pack kept contained within the jacket.

Abstract: A multielement magnetic head is formed with a closure section having a nonmagnetic ceramic substrate on which a thin layer of magnetic ferrite is deposited and processed. The thin ferrite layer is cut to define the separate transducing elements and data track separation. The closure section is joined to a wafer formed from a ferrite substrate and a thin film conductive coil means.

Abstract: The invention relates to a method of recording a television signal of the kind in which the signal is recorded on a relatively slowly moving tape in a plurality of inclined tracks by a plurality of recording heads carried at the periphery of a head wheel rotating at a relatively high speed in a plane non-parallel to the direction of tape motion. The head wheel executes m complete revolutions for each n complete television pictures, where the ratio m/n is non-integral, and control signals having a frequency of 1/n of the picture frequency are recorded along a longitudinal control track by a fixed head. For recording signals according to the 625 line European standard, m is chosen to be 25 and n is chosen to be 2. For the U.S. 525 line standard, m is 21 and n is 2. In both cases 25 lines per track are recorded.

Abstract: A control apparatus for controlling a microcassette tape transport of one motor type includes a first designation means (106) for designating a constant speed transport mode, a rewind mode, and a fast forward mode; a second designation means (124) for designation a direction of the motor rotation; a third designating means (122) for designating a direction of the tape transport. In order to effect the control of a tape transport on the basis of the combination of designations by the first, second and third designation means, the apparatus further includes a first memory means (301) which operates, e.g.

Abstract: An improved charged coupled device time base corrector system to compensate for a change in the phase or frequency of input video signals, as occurs in the playback of a video tape recorder, by changing the nominal delay through the corrector, comprising, in combination, an input feedback circuit and an output feedback circuit. The input feedback circuit includes two cascaded infinite gain circuits, an infinite gain phase detector followed by an infinite gain voltage amplifier which gives an error voltage that controls the frequency of the voltage controlled oscillator (VCO) utilized to control the system delay. The output servo loop always adapts itself to the input error voltage. The VCO is thereby driven at a rate of change of its frequency proportional to the incoming error signal. .