Abstract: An information recording apparatus including a device for driving an optical-disk's master disk, an electron lens barrel for having an electron beam irradiate a recording surface of a disk, a translational device for producing, between the disk and the electron lens barrel, a relative movement in a direction parallel to the recording surface and a container for enclosing the elements of the apparatus adapted to support a vacuum atmosphere. The driving device includes a turn table 4, a spindle 14a for supporting the turn table, a motor 14 for driving the spindle, and a magnetic shield for preventing magnetic fields of the motor from leaking outward. The motor is enclosed in the shield to prevent its magnetic fields from affecting the electron beam, which makes it possible to record information with high accuracy. The use of the motor as a drive source realizes easier and more responsive control of the turn table than that in the prior art.

Abstract: A disc player comprises an optical scanning device (13) with a turntable (17), which is rotatable about an axis of rotation (17a) and which has a supporting surface (17b) for supporting an information disc, and with a disc-shaped disc carrier (15), which is rotatable about an axis of rotation (15a) and which has carrying surfaces (51) for information discs. The disc player has a driving device comprising a command element (63) which is rotatable about an axis of rotation (63a) and which has first means for cooperation with guide means to guide the turntable between a play position and a rest position and second means for cooperation with the disc carrier to rotate the disc carrier between well-defined disc-carrier positions.

Abstract: The instability of a cage in a precision ball bearing at high speeds may be eliminated by controlling the position of the cage. The control of a position of a cage is accomplished by forming three ball pockets or holes in the cage for the balls of the ball bearing assembly to a dimension that will result in a tight running fit between the ball and the ball pocket. A tight running fit between the ball and the cage is found in three of the ball pockets in a ball bearing assembly while the diameter of the large ball pockets or other remaining ball pockets is enlarged to provide a clearance between the balls and the cage which is at least twice the clearance between the ball and the guide ball pocket having the tight running fit, and preferably three to five times that clearance. When properly lubricated, the tight running fit will insure stabilization and control of the cage so that the cage remains stable at high rotational speeds.

Abstract: A disk playback apparatus designed such that the linear velocity of the disk is stabilized during a short period corresponding to one to several revolutions of the disk and occurrence therein of vibration and noise is suppressed is disclosed. The apparatus is characterized in that the revolving axis of the turntable on which the disk is mounted is driven by a low-torque spindle motor and the wheel effect of the revolving axis or the spindle motor is made larger.

Abstract: A drive system for rotating a disk includes a housing having a planar element with a working surface which includes a spindle which facilitates rotational movement of the disk relative to the drive assembly. A plurality of orifices extend through planar element at an acute angle relative to the working surface and are arranged in a circular array. A conduit assembly delivers fluid to the housing. The fluid exits through the orifices outlets to provide a motive force for rotating the disk around the spindle, while also providing a pressure differential to support the medium.

Abstract: A casing of a sound record playing apparatus includes of an upper body (1B) and a lower body (1A), and a vibration plate (16) is formed by reducing a thickness of a part of the upper body. An inner surface of the vibration plate is in abutment with a pickup (13) to amplify the vibrations of the pickup. Thus, a conical speaker which has been used conventionary can be eliminated, and the thickness of the recording disk reproducing apparatus is reduced. Expansion member (6) includes cam surfaces (71b, 72b) which force the grooved recording disk (2) away from the pickup (13) when the expansion member (6) is rotated conversely.

Abstract: A disk drive device is disclosed including a supporting mechanism for supporting a plurality of magnetic disks, a single motor, and a transmitting mechanism. The supporting mechanism comprises a plurality of bearing mechanisms, each of which rotatably supports each of the magnetic disks, respectively. Each bearing mechanisms is formed as a tube, and a rotatable shaft is connected to each disk and rotatably supported in each tubular bearing mechanism. The rotatable shaft is provided with grooves which generate a pumping effect when a fluid is passed therethrough, whereby the rotatable shaft is supported in the tubular bearing mechanism without friction therebetween. The transmitting mechanism comprises an endless belt for transmitting a rotation of the motor to the supporting mechanism.

Abstract: A device is disclosed which includes a frame (1), a turntable (3), and an electromagnetic drive unit comprising a stator section (5) and a rotor section (7). The turntable, which is rotatable about a shaft (19), and a frame portion (4) have facing annular bearing surfaces (21A and 21B respectively) to form a dynamic axial bearing. The bearing surfaces are coaxial with the shaft and radially spaced from this shaft. One of the bearing surfaces has at least one pattern of grooves which causes a pressure to be built up in a medium present between the bearing surfaces during rotation of the rotor section relative to the stator section.

Abstract: A pickup movement device includes a plurality of electromagnetic driving coils for moving a pickup. It supplies a driving signal to these plurality of electromagnetic driving coils for the purpose of accessing a target track. The movement speed of the pickup can be detected by a track error signal during access. This track error signal is monitored at access time to see whether the pickup device is within an allowable range. When it is out of the allowable range, a speed signal is detected by one of the plurality of electromagnetic driving coils, which is used to prevent a runaway of the pickup.

Abstract: A disk drive motor and spindle assembly includes a drive motor having a drive shaft defining an axis of rotation, a centering hub, and a flat spiral spring. The centering hub has a spherical disk-receiving surface section about a sphere center and a cavity extending therein from its lower edge. The spiral spring mounts the centering hub with respect to the drive shaft with the sphere center located on the axis of rotation and in the plane of the spring.

Abstract: An optical disc cartridge with a flexible optical storage medium, stabilized during rotation by a Bernoulli surface, is described. A flexible optical disc having an active layer capable of storing information is mounted within a rigid disc cartridge. A Bernoulli surface is provided on an inside face of the disc cartridge, in close proximity to the flexible disc, to thereby stabilize the flexible disc during rotation. The disc is rotated in order to access locations thereon during information storage and retrieval. Additionally, optical access to these locations during information storage and retrieval is also provided by the stabilizing Bernoulli surface.

Abstract: A rotation control system for disk player in which the player detects the size of a disk housed in the player, varies the starting torque to be given to the disk motor in response to the detected size, and controls the disk motor so as to require substantially the same length of time before a prescribed rotational frequency is attained, irrespective of the size of the disk.

Abstract: A recording apparatus comprises a recording head arranged to record signals on a recording medium; a motor for shifting a relative position between the recording medium and the recording head; and a control circuit arranged to apply electric energy to the motor in starting the motor either in a first mode in which the electric energy is limited to a first value or in a second mode in which the electric energy is limited to a second value which is lower than the first value. Also disclosed is a motor control circuit which is highly suited to the recording apparatus. Detecting apparatus is also included to detect whether the power source is an A.C. adapter or a battery.

Abstract: In a control system for a disc player for a CLV (constant linear velocity) type disc, in order to control a rotation of a spindle motor in response to a location of the disc to be read, there is provided a tachometer coupled to the motor for generating a rotation signal having a frequency corresponding to a rotation of the motor, signal generator for generating a reference signal having a frequency corresponding to the rotation suitable to the location to be read, and a drive circuit for controlling the rotation of the motor so that rotation is effected in accordance with the reference signal.

Abstract: A disk driving device which can be reduced in production cost and in overall thickness and can prevent a circuit board from being damaged upon ejection of a disk cartridge therefrom. The disk driving device comprises a spindle shaft mounted for rotation relative to a base by means of a metal bearing, a spindle fitted at an end of the spindle shaft remote from the base and having carried thereon a turntable for receiving a disk for integral rotation, a stator yoke secured to the base, and a buffer member mounted on a face of a driving magnet opposing to a circuit board mounted on the base. The driving magnet secured to the spindle for electromagnetically cooperating with a driving coil secured to the circuit board to rotate the spindle is located between the circuit board and the stator yoke.

Abstract: Apparatus for recording or reading information on a rotating information disc (19) comprises a turntable (11) journalled in a deck plate (1), which comprises a centering member (13), and a clamping device (21) for clamping the information disc onto the turntable. The clamping device comprises a support (5), which is movable between an operating position and a rest position, and a disc pressure member (23) coupled thereto. A flat electric drive unit (31) arranged in the clamping device serves for rotating an information disc placed on the turntable and comprises a stator section (35) which is secured to the support and a rotor section (33) which is secured to the pressure member.

Abstract: A recording or reproducing device in which current is supplied to the spindle motor which drives the disk to produce reverse torque in response to a stop signal when the disk is rotating. The beginning of reverse rotation is detected and the supply interrupted in response thereto.

Abstract: An electromagnetic drive unit comprises a stator (2) and an armature (4) which is pivotable about a pivotal axis (5) and which cooperates with the stator via an air gap. In order to minimize the volume and to obtain a maximum efficiency, the armature is arranged coaxially around the stator, the stator comprising at least two polepieces (6A) which are interconnected by a stator member (6B) carrying a coil (8). The armature comprises a plurality of radially magnetized poles (28A, 28B) which correspond in number to at least the number of polepieces, which poles are tangentially juxtaposed with alternately opposite polarities.

Abstract: A record disk drive is disclosed which includes a rotating drive shaft and means for receiving a record disk. A torque-transmitting helical spring clutch drivingly interconnects the shaft and the disk. The clutch includes a first coil portion which is in driven engagement with the shaft upon rotation of the shaft in a certain direction relative to the receive disk. A second coil portion of the clutch is continuous with, but eccentric to, the first coil portion. Abutment means on the second coil portion are normally in driving engagement with a received disk, but means are provided for shifting the second coil portion toward a position concentric with the first coil portion, whereupon the abutment means moves out of engagement with the received disk, and thereby disengages the clutch. The shifting means may be a cylindrical sleeve which is axially slidable over the helical spring clutch to move the second coil portion toward its concentric position relative to the first coil portion.

Abstract: A turntable for placing a recording disk such as an optical information storage disk has a rotatable shaft to which an electrically conductive rotor is fixed. Inner and outer stators are disposed in confronting relation to each other with the rotor interposed therebetween. Each stator has a C shape with a recess in which there is placed one end of a radial feed unit for moving a pickup head radially across the turntable for recording information on or retrieving information from the disk on the turntable while the latter is being rotated. The outer stator comprises a comb-shaped block having a plurality of teeth with coils wound thereon in different phases. When sinusoidal currents are supplied to the coils, the stator produces a moving sinusoidal magnetic field to rotate the rotor according to the principles of a polyphase induction motor. The rotor may double as the turntable.

Abstract: A venturi or other air deflecting means is provided on the inside of the casing of a disc drive. The venturi or air deflecting means is arranged so that air, which is caused to move by the rotating disc, passes it and creates the lowest pressure inside the disc casing. This low pressure area is communicated to atmospheric pressure.

Abstract: A record disc player apparatus has a frame including an entrance for a disc inserted through the entrance to a loading position, the disc being movable from the loading position to a playing position in an operating plane. A drive spindle mounted perpendicularly relative to the operating plane and aligned with the center of a disc in loading position is driven by a drive motor having a wound stator, a permanent magnet rotor, and a drive shaft mounted for movement axially of the spindle from a disc loading position in which the rotor is offset from the stator to a disc playing position in which the rotor is proximate to and rotated by the magnetic field of the stator. The stator of the motor is formed as a printed circuit on a board.

Abstract: An optical disc assembly includes an optical disc on which signals are recorded, and from which the signals are optically reproduced; a closed casing rotatably containing the optical disc, and having a transparent portion; and a rotor fixed at the center of the optical disc and magnetically coupleable with an external rotating magnetic field to be rotated therewith. An optical disc assembly includes a rotating magnetic field generating device arranged outside of the closed casing and concentrically with the optical disc to drive the latter without contact.

Abstract: A record player is equipped with a tonearm control which enables the record player to perform an automatic music search, that is, the pickup device of the tone arm may be automatically controlled to be set down at the beginning of a selected song. It may happen that the center of the record is slightly displaced from the center of the turntable, so that different angular segments of the recorded tracks lie at different radial distances from the turntable center. The present tonearm control compensates for this by detecting the radial and angular position of the beginning of the selected song and by setting down the pickup device at this position. The radial position of the beginning of each song is measured along a radial reference detection line while the turntable is at rest at an initial angular position. Then, while the turntable is rotating, the tone arm is moved across the record until the pickup device reaches the measured radial position of the beginning of the selected song.

Abstract: In a simplified sound-reproducing device, a motor is coupled by a transmission to a record disc for driving the record disc and an external output shaft extending outside from the casing of the device.Transmission consists of a driving wheel fixed to an extension of a center shaft and a follower wheel fixed to the output shaft which is disposed parallel to the center shaft. The driving wheel and the follower wheel are arranged to either mesh or not mesh with each other depending on their relative relationship in the axial direction by caused axial shifting of the center shaft.Virtue of the construction as mentioned above, the device can drive, by relying on the driving motor alone, another device or attachment subsequent to or concurrent with sound reproduction.

Abstract: A disc rotating apparatus for use in a dic player. The disc rotating apparatus is provided with a turntable adapted for receiving a disc and a clamping mechanism for clamping the disc against the turntable in cooperation with the turntable. The disc clamping mechanism includes a plunger slidable along an axis of the plunger and rotatable about the same axis, a holder for holding the plunger and a magnetic propelling mechanism for propelling the plunger toward the disc received on the turntable. The magnetic propelling mechanism urges the plunger against the disc by means of magnetic force caused by a permanent magnet.

Abstract: A disc record apparatus having a fixed housing including an entrance slot for a disc record and a surface to slidably receive a disc record inserted edge first in its own plane through said slot to a playing position has a drive spindle for the disc record mounted in a spindle or motor housing for translation axially of the spindle and perpendicularly relative to the plane of the disc record. The spindle is movable in tranlation from an insertion position displaced from the plane of the record to an operative position in engagement centrally with a disc record in playing position for rotating the disc record. A motor driven cam member translates the spindle housing. A movable gate is provided for the entrance slot and the motor driven cam member is connected for opening and closing the gate so that a disc record may be inserted or ejected coordinated with translation movement of the spindle.

Abstract: A straight line tracking turntable sound reproducing system. A conventional rotatably mounted turntable is unconventionally mounted on linear tracks for linear travel toward a substantially fixed position pivotally mounted stylus-carrying tone arm.A servomechanism comprising a sensing device and a motor means controls the rate of linear travel of said turntable so that displacement of said tone arm is minimized. The sensing device detects displacement of the tone arm and signals the motor means to increase or decrease the rate of turntable linear motion as required.Mechanical pinch clutch means are provided to allow manual re-positioning of said turntable to any pre-selected position along its linear path.

Abstract: A turntable drive system for use with a video disc player employs a low cost magnetic sensor, such as a Hall effect device, for turntable speed control. An integral motor mounting bracket and flux concentrator is positioned with respect to a ring magnet having a plurality of permanently magnetized poles of alternate polarity along its periphery such that the magnetic field of the magnetized ring passes through an active surface of the magnetic sensor. The Hall effect device provides an output representative of the rotary motion of the ring magnet which is fixed to the turntable. The output of the Hall effect device is compared to a reference oscillator and an error signal indicative of drift in the rotary speed of turntable from the predetermined speed is fed to a DC motor for driving the turntable at the desired rotational speed.

Abstract: A reproducing apparatus for information-carrying records, which apparatus comprises:a housing with an opening for inserting such records, which opening is situated at housing front,a drive mechanism for the rotary drive of the records about an axis of rotation, which mechanism is accommodated in the housing,a turntable for supporting the records, which turntable is axially movable between a lowered position and an operating position, anda lifting device for moving the turntable between the lowered position and the operating position,in which apparatusthere is provided a support (14), which supports the turntable (13) in the lowered position,the turntable (13) can be lifted off the support (14) into the operating position by means of the lifting device (35, 45, 47, 49, 51), andthere is provided a positioning device (11) for moving the support (14) and the turntable (13) carried by said support between the lowered position of the turntable and a position in which it extends at least partly from the housing (3).

Abstract: A method of assembling a belt drive of a record player includes engaging the belt around a drum of a record player, holding the belt with a hook member, engaging the turntable with a deck plate, rotating the turntable by hand until the belt engages an abutment which causes the belt to disengage the hook and engage the motor driving spindle. The invention also provides a record player for use in the method.

Abstract: An assembly comprising a drive motor connected to a member to be rotated by a transmission means which is liable to slip when the rotating member is subjected to a loading thereon, includes a compensation circuit connected to the motor control circuit and operable to apply to the latter a compensation signal proportional to the change in a parameter directly related to the motor torque, thereby to compensate for slipping of the transmission means.

Abstract: A phonographic source has a turntable with a central hub joined by radial arms to a peripheral rim in which the weight of the turntable is concentrated so as to expose at least a major part of the underside of a record supported on the turntable. The record is supported at the hub, and by the arms and/or the rim, and in a modification by one or more concentric rings. The central spindle of the turntable for reception in the record center hole can be connected to the turntable drive shaft only indirectly, by a further construction in which the drive shaft connects with a lower turntable member connected with an upper turntable member for supporting the record by a concentric ring between the members. The source can include a pick-up arm having a counter-balance portion extending from the front position away from the portion carrying the cartridge, which counterbalance portion has at least approximately the shape of the other portion.