Abstract: In a magnetic disc memory apparatus in which a magnetic head is in contact with a surface of a magnetic disc when the disc is stationary and caused to float upon rotation of the disc, the magnetic head contacting the magnetic disc is slightly moved in the radial direction of the disc immediately before rotation of the disc, whereby the rotation of the magnetic disc is started after adhesion between the magnetic disc and the magnetic head has been obviated.
Abstract: In a head shift mechanism in a tape player to shift a head to a reproducing position and hold it there by means of a solenoid driven by a driving signal from a solenoid driving device, an improvement comprising a solenoid driving signal generator, a counter connected to the solenoid driving signal generator for counting up solenoid driving signals from the solenoid driving signal generator, and a head shift stopping device connected to the counter for receiving count completion signal from the counter to actuate to stop action of the head shift solenoid.
Abstract: A tape transport system has reduced unreeled tape length by employing only one tape-deflecting bearing on each side of the read/write head. These bearings are fixed in position, but capable of pneumatically sensing tape tension. This tape tension is sensed at both bearings, and used to counteract the effects of stiction at the head.
Abstract: A dual channel read recovery system having a high resolution channel and a low resolution channel and logic for recovering digital information from the high and low resolution signals from the channels, is improved by the inclusion of a variable delay in the low resolution channel. The variable delay is responsive to the high and low resolution signals to more closely match the delays in both channels.
Abstract: An apparatus for reproducing information from a track of a magnetic record carrier by means of a reproducing head divided into two reproducing portions. The apparatus comprises an amplifier circuit having a pair of input terminals, connected to the outputs of the two reproducing portions, a first signal combination unit, at least one variable gain amplifier and an output terminal. The controllable amplifier is connected between the output of the signal combination unit and the output terminal of the amplifier circuit. The gain of the amplifier is controlled in such a way that upon application of the two signals to the input terminals of the amplifier circuit, a signal is obtained on the output terminal having an amplitude u which is in a fixed ratio to the amplitude of the larger of the two signals applied to the two input terminals.
Abstract: A switch assembly is provided for a tape drive adapted to receive a tape cartridge. The assembly comprises a housing, first and second switches fixedly mounted on the housing, and first and second plungers mounted for reciprocal movement on the housing to actuate the first and second switches, respectively. The housing includes three orthogonal reference surfaces, all of which engage the tape drive to locate the assembly in proper relationship to the tape drive. The plungers are responsive to the tape cartridge to actuate the first switch when the tape cartridge is properly mounted on the drive and to actuate the second switch when the tape cartridge is not write-protected. The assembly may include a light source and a light-responsive switch which, together with a reflector in the tape cartridge, cooperate to detect position-indicating tape apertures.
Abstract: A magnetic disk storage unit is proposed for cleaning away dust particles on a disk by a magnetic head 7, which is in contact with the surface of the magnetic disk when a magnetic disk 3 is stationary or rotated at a low speed, and which is floated away from the surface of the magnetic disk, as the revolution rate of the magnetic disk increases.When the magnetic disk starts to rotate or when the disk is rotating at a low speed in a continuous rotation, the magnetic head is reciprocated in the radial direction of the magnetic disk, thereby to peel off the dust particles deposited on the surface of the magnetic disk and the head with the removed dust particles then being collected by a filter.
Abstract: A video disc system adapted for use with a recordable, master storage, video disc and a prerecorded, transfer storage, video disc comprises a turntable for rotating the master disc and the transfer disc in synchronism, a playback head for reading the video signals recorded on the transfer disc, electronic circuitry for editing the video signals read by the playback head, and a record head for recording the edited video signals onto the master disc.
Abstract: An auto-reverse type cassette tape player having a head base rockably mounted on the front side of a bed and carrying a pair of magnetic heads, so that the magnetic heads are switched in a seesaw-like manner as the tape running direction is switched as a result of a switching between two pinch rollers which cooperate with corresponding capstan shafts.
Abstract: There is disclosed a head assembly for use in a magneto-optic recording/playback system which includes a memory medium having a magnetic coating having a magnetic anisotropy in a vertical direction. A light beam is applied to the memory medium for recording and reproduction of information. The head assembly includes a polarizing prism and a Faraday effect element in an optical path for the light beam. There is needed only the single polarizer.
Abstract: A tape cassette loading device comprises a chassis on which a tape cassette is mounted, a pair of guide pins protruding from the chassis and capable of being fitted in guide holes of the tape cassette in a loaded position, a taper surface formed around the guide pin at a given height above the chassis so as to be tapered toward the extended end portion of the guide pin, and an ejection mechanism facing the front portion of the bottom surface of the tape cassette in the loaded position and capable of advancing and retreating along the guide pin. In the final ejected position the cassette rests on the upper tapered portion of the guide or guides.
Abstract: A cassette tape recording and/or reproducing apparatus has a substantially rectangular chassis with a perimeter approximately coextensive with a tape cassette to be operatively positioned in a cassette holder at one side of the chassis, a tape transport mechanism including reel shafts extending through the chassis for engaging respective reels in a tape cassette operatively positioned against the chassis, and a gear transmission for selectively driving the reel shafts in accordance with a plurality of operating modes, such gear transmission consisting of a plurality of gears disposed at the other side of the chassis for rotation about axes normal to the chassis, with certain of the gears being axially displaceable for the changing from one to another of the operating modes, and push-buttons all disposed at the other side of the chassis and being selectively manually actuable normal to the chassis from extended to depressed positions for displacing respective axially movable gears for correspondingly changing
Abstract: A locking device for a magnetic tape cassette in a magnetic tape device has a lever disposed below the insertion slot; a blocking arm projecting out of the housing; a thrust arm; and an ejector arm. When a magnetic tape cassette is locked in with the locking arm, the thrust arm engages via a wedge with a cartridge-like carrier provided with three rotary bodies and by upward movement of the carrier towards the insertion slot presses the rotary bodies into the insertion slot from below and against the magnetic tape cassette. The magnetic tape cassette is thereby securely held at the reference points. When releasing the locking arm, the magnetic tape cassette is ejected by the pre-stressed ejector arm.
Abstract: A magnetoresistant transducer is described for reading very high-density a. The magnetoresistant transducer (TMRI) includes at least one magnetoresistor (MRI) of an anisotropic magnetic material placed perpendicular to the direction in which the data of a medium (SM) pass. The axis (AFAI) of easy magnetization of the magnetoresistor is normal to the medium and includes a thin, mono-range or single domain magnetic anisotropic layer (CI) normal to the medium and to the direction in which the data pass. The mono-range or single domain layer is strongly coupled magnetically with the magnetoresistor, and its axis of easy magnetization (AFACI) is normal to the medium and opposite in direction to the axis of easy magnetization of the magnetoresistor. The invention is particularly applicable to the reading of magnetic tapes and disks containing high density data.
February 23, 1982
Date of Patent:
December 11, 1984
Compagnie Internationale pour l'Informatique Cii-Honeywell Bull
Abstract: A mounting structure for tape guide elements, for use with a guide drum adapted to have a tape wound in an .OMEGA.-shaped configuration around its periphery, has a base fixed adjacent to the root portion of the drum and has first and second guide supports for the guide elements. At least one of the guide elements is movable relative to the base between an operative position close to the drum in which it guides the tape about the drum and an inoperative position at a further distance from both the other guide element and the periphery of the drum. A pair of spaced apart positioning members engage the periphery of the drum at its root portion for accurately locating the operative positions of the tape guide elements.
Abstract: A transducer-carriage assembly is shown which includes an intermediate adapter that enables the subassembly to be fabricated in a manner that eliminates the effect of tolerances in the component parts, prior to incorporation into the final assembly, with respect to penetration, pitch and roll of the transducer.
December 24, 1981
Date of Patent:
October 9, 1984
International Business Machines Corporation
Abstract: A cleaning cassette for a tape unit includes a supply reel and a take-up reel, with a cleaning ribbon mounted therebetween. The cleaning ribbon extends around various support surfaces in the cassette, and passes two cleaning stations. The first cleaning station utilizes a spring biased plunger to force the cleaning ribbon against a pinch roller being cleaned. A traction sleeve is positioned between the capstan and the pinch roller to enhance the frictional engagement between the capstan and the pinch roller. At the second cleaning station, the cleaning ribbon passes between the capstan and the pinch roller. Once again, a traction sleeve is provided between the capstan and the pinch roller, and in this case the traction sleeve is offset with respect to the cleaning ribbon. Funnel-shaped openings and distribution channels are provided in the said shell to introduce a liquid such as a cleaning solvent onto the cleaning ribbon near the cleaning stations.
Abstract: A tape guide mechanism for a tape recorder comprises a pair of first tape guides severally attached to the free end portions of a head lever which has a rotation center in the middle thereof, each of the first tape guides being located on the opposite side of a magnetic head on each side of the head lever to a pinch roller on a pinch roller lever and on the side where its corresponding magnetic head lies. Further, a pair of second tape guides are disposed on the pinch roller lever so as to embrace the pinch roller from both sides thereof, thereby partially covering the pinch roller.
Abstract: A floppy disk drive with automatic disc clamping and ejection is disclosed. The movement of the linear actuator is used to provide both the clamping and ejection, without other drive means. A pair of magnetic heads, positioned on opposing sides of a drive wheel, are fixed to a carriage, one engages the upper surface of the disc, the other the lower surface. Neither head moves relative to the other. The drive components are easily assembled providing a relatively inexpensive, yet reliable drive.
February 24, 1982
Date of Patent:
August 14, 1984
Apple Computer, Inc.
Richard Jordan, William Bull, Robert L. Ciardella, Robert Taggart, Frederick R. Holt
Abstract: An erroneous erasure preventing piece to be detected is formed simultaneously with disk cassette covers by a molding process. The piece has a configuration which enables it to be slidably remounted to the cassette disk covers after being torn off the cover.