Abstract: A plunger operating mechanism in a tape player comprises: a head lock plate linked to a head plate normally biased to its withdrawal position by a stop mode spring; a drive means engaging the head lock plate to pull it in a direction for advance of the head plate; a lock means to lock the head lock plate brought ahead by the drive means to place the head plate at the advance position; stress plates individually linked to two attractive plungers and locked by the plungers when energized so that the engagement between the head lock plate and the drive means is maintained by a least one stress plate locked by the energized plunger; fast-forwarding and rewinding control plates linked to the two stress plates to establish the fast-forwarding or rewinding mode so that one of the control plates is set in the fast-forwarding or rewinding mode when one of the plungers is energized but neither control plate is set in a mode other than the fast-forwarding and rewinding mode in which both plungers are energized; position

Abstract: A contactless (flying) transducer for scanning a record or recording disc is mounted near the free end of a pivoted arm which is driven in rotation about its pivot by the tangential drive provided by a restrained nut on a threaded motor-driven spindle. A pin extending fron the nut slides without play in a lengthwise groove at the free end of the arm. Rapid operation of the electric motor makes it easy to shift from one part of the record to another and slow movement makes it easy to register precisely with a track. Still finer movement is possible electrically by shifting the transducer on the arm.

Abstract: A magnetic disc cartridge is composed of a pair of upper and lower case members superimposed one upon the other so as to form a hard case to accommodate a magnetic disc therein. An aperture for access of a read-write head to the magnetic disc extends in a radial direction, which aperture is selectively covered by a shutter. The case has a groove on the peripheral edge thereof to receive a shutter actuation pin. The groove extends across the adjoining surfaces of the two case members and is formed by a wall member extending integrally from one of the two case members towards the other so as to hide a joining line between the two case members.

Abstract: Disclosed is a perpendicular magnetic recording medium wherein an underlayer made of a material containing Si and/or Ge as its principal ingredient is deposited on a substrate, and a perpendicular magnetic film made of a Co-based alloy is deposited on the underlayer. With the perpendicular magnetic recording medium, the perpendicular magnetic film has an enhanced degree of C-axis orientation, and the bond strength between the perpendicular magnetic film and the substrate is also enhanced when the substrate is non-metallic.

Abstract: A magnetic tape cassette of the type in which the tape is extracted from the cassette through tape drawing openings formed at opposite sides of a central opening in the cassette for recording and reproducing. In accordance with the invention, each of the tape drawing openings in a rectangular opening defined by a lower rib protruding from the lower half case and confronting one edge of the magnetic tape, a guide formed integrally with the lower rib and having a sliding surface with which a rear surface of the magnetic tape contacts, an upper rib protruding from the upper half case and confronting the other edge of the magnetic tape, and a cassette case wall confronting a front surface of the magnetic tape. The upper rib is recessed farther inwardly of the guide than the sliding surface.

Abstract: A magnetic recording and reproducing system is provided with a cleaning mechanism wherein a cleaning pad contacts a rotary magnetic head to clean said magnetic head during inertial rotation of said magnetic head.

Abstract: A tape cassette is provided with a slider serving as a reel lock releasing element and which is movable in the front-to-rear direction near the rear of the cassette, along a path defined by a guide. A guide groove is formed in the underside of the cassette in alignment with the guide for the slider. The slider has a downward projection extending into the guide groove through an elongated opening in the guide. The downward projection is abutted by a projection built into the playback unit, and which is received in the guide groove for guiding the cassette during its insertion into the playback unit or VTR. Therefore, insertion of the cassette causes the cassette guiding projection to displace the slider for releasing the tape reels.

Abstract: In a hard disk drive with a closed housing (10) enclosing a magnetic disk pack (24,26) and a carrier arrangement (32) for magnetic heads (36), permanent-magnet or electromagnetic erase heads (44,62) are arranged in this which can be operated independently of the magnetic heads (36).

Abstract: A magnetic tape cassette having an improved tape guide structure and ease of assembly. Tape guides are arranged on both sides of the front opening of the magnetic cassette, the guides being adapted to be brought into sliding contact with the magnetic tape to guide the latter. Each tape guide is in the form of a solid post. Holding members adapted to hold these tape guides are formed on one of upper and lower half cases of the cassette, and tape guides are fixedly inserted into grooves formed in the holding members, with each groove having a portion which is broader than its opening.

Abstract: A magnetic thin film head used for perpendicular magnetic recording and reproduction. The head includes a magneto-resistive element and a flux guide made of high permeability thin film whose one end portion faces a perpendicular magnetic recording medium. The magnetic flux produced by the magnetization signal on the perpendicular magnetic recording medium is led to the magneto-resistive element through the flux guide. The head also includes electrodes for supplying an electric current londitudinally to the magneto-resistive element, and high permeability members for introducing the magnetic flux through the magneto-resistive element back to the perpendicular magnetic recording medium. The head further includes a exciting means for the flux guide.

Abstract: A head travelling mechanism for a floppy disk drive including a stepping motor which is provided with a pair of stator coils arranged in both end sides of its casing. These two stator coils are not only supplied exciting electric current with predetermined combined phases to drive the feeding belt but also the direction of these two stator coils is in parallel with the travelling direction of the magnetic heads, and combination of exciting phases in the stator coils enables the inclination of the motor shaft of the stepping motor to be absorbed as a sideways motion of the feeding belt so that the travelling error of the magnetic heads can be reduced to the minimum.

Abstract: A magnetic disc cassette has a casing for enclosing a magnetic disc therein and a shutter provided on the casing and slideably moveable to expose or cover a head access opening in the casing. The shutter is molded from a synthetic resin to have a generally U-shaped cross section and has opposed edges which closely approach each other and are separated by less than the width of the casing when the shutter is removed from the casing.

Abstract: The support for a magnetic recording disc according to the invention comprises a metal disk covered by an organic coating and, on the latter, a thin, hard coating of a material based on hydrous silicate or silica.

Abstract: A one way clutch assembly, including a frame, a bearing member having a vertical, central bore therein fixedly secured to the frame, a pulley rotatably mounted on the bearng member, a vertical, drive spindle rotatably mounted within the bearing member central bore, a retainer fixedly secured on the lower protruding end of the bearing member, a circular cam plate rotatably mounted on the retainer, the cam plate having an interior camming surface for effecting radially inward and outward movement and an arcuate recess, a mounting stud fixedly secured to and projecting upwardly from the pulley through the arcuate recess in the cam plate, a pawl rotatably mounted at one end on the mounting stud and having a pin at the other end extending into the interior camming surface of the cam plate, wherein the pawl is movable radially inwardly and outwardly by the interior camming surface, and a ratchet plate fixedly mounted on the lower end of the drive spindle for rotation therewith, the ratchet plate having a plurality

Abstract: A magnetic tape cassette intended for applications such as digital recording where extremely tight tolerances are imposed on the amount of widthwise deviation of the tape. A partition member, dividing the cassette into a recording and reproducing region and a tape winding core accommodating region, is molded separately from the two halves of the shell of the cassette. The partition member has a partition wall having guide walls protruding forwardly therefrom symmetrically with respect to the center line of the cassette. The pair of guide walls closest to the center line have front portions of reduced height so that the upper and lower portions thereof do not contact the cassette halves.

Abstract: A cassette loading mechanism for a cassette deck which contributes to the compactness of the deck. The loading mechanism includes a movable member which engages a cassette and which is movably mounted to slide in directions in which the cassette is inserted and ejected. The movable member is biased in the ejecting direction. A cassette holder is movable between a raised position where the inserted cassette is held and a lowered position where the cassette as held is set in a play position, the cassette holder being biased in the direction of the lowered position. A control arm, which is rotatably mounted on a frame, controls the movement of the cassette holder towards the lowered position. A lock arm, rotatably mounted on the control arm, locks the movable member when the movable member is moved a predetermined distance in the insertion direction of the cassette. A single biasing device biases the control arm in a control direction and the lock arm in a locking direction.

Abstract: A magnetic recording/reproducing apparatus having an opening and closing door for loading and unloading a magnetic sheet pack, the door being adapted to override a position wherein the door is locked and then to return thereto, upon loading the magnetic sheet pack. The door has a pressure member which, during the overriding movement of the door, presses a center core of the magnetic sheet to forcibly mount the magnetic sheet onto a spindle. The pressure member is spaced from the center core when the door retreats to its locked position, in which the door cannot move in any direction. A switching member is provided so as to control a driving motor for the spindle in cooperation with the action of a mechanical device for locking the door.

Abstract: A motor installed on a wall of a cassette housing operates a placement gear and a rotating member for safely placing a cassette holder on a deck and then also operates a ring gear, which is installed on the deck, in order to load video tape for reproduction, thereby making it possible that both the action of placing the cassette holder on the deck and the action of loading the tape for reproduction can be achieved by using only one motor. A combination of a sector gear and a cam or a disc with a built-in spring can also be used in order to lock the cassette holder properly after the cassette holder, with the cassette held therein, is placed on the deck.

Abstract: A magnetic disk cartridge comprises a case rotatably housing a magnetic disk, and a shutter slidably fitted onto the case for opening and closing window sections provided in the case for insertion of a magnetic head. The shutter is always urged by a spring to close the window sections. At least one end of the spring is secured to an engagement member having approximately cylindrical protrusions which are fitted into grooves positioned for resilient deformation in the case or in the shutter.

Abstract: A cartridge includes a shutter movably mounted along and on outside surfaces of a cartridge box for opening or closing a central hole and a head slit together, a slider for driving the shutter, and guide grooves provided outside a receptacle for a disk and serving to guide the slider. The shutter normally closes the central hole and the head slit to permit the cartridge to completely surround the disk, thereby preventing entry of dust from the outside. Even when the slider is broken by accident, the disk is immune from scratches to be constantly held in a good state since the slider is moved on the outside of the receptacle. Moreover, a drive for the shutter is provided forwardly of the center of the receptacle to enable increasing the recording capacity of the disk and miniaturizing the cartridge.