Abstract: One end of each of a plurality of plate springs is fixed to an optical pickup body slidably supported by supporting shafts through sliding bearings, and each of a plurality of bearings is fixed to the other end of each of the plate springs. The bearings are pressed against the supporting shafts by the energizing force of the plate springs, and a force is applied to the optical pickup body by the pressing force of the bearings in a direction opposite to gravity.

Abstract: An information memory medium (10) includes disk-shaped substrates (30a, 30b) and recording layers (32a, 32b). It also has a centering member (38a, 38b) whose coefficient of thermal expansion resembles that of the substrates (30a, 30b). Two flat magnetic members (40a, 40b) are situated in annular depressions (68a, 68b) provided in the centering member. The annular depressions are larger than the magnetic members so that differences in thermal expansion can be absorbed.

Abstract: An information processing apparatus includes a casing having a loading slot through which a cartridge is inserted into and taken out of the casing. In the casing is arranged an information processing unit which has a drive base mechanism for information processing with an optical disc in the cartridge and a loading mechanism for loading and unloading the cartridge onto and from the drive base mechanism. The processing unit is elastically supported in the casing by a vibration insulating mechanism so that vibrations acting on the unit are absorbed. While a cartridge is being inserted into or taken out of the casing, the processing unit is locked at a specified position by a locking mechanism. When the cartridge is completely loaded onto the drive base mechanism, the locking mechanism releases the locked state of the unit.

Abstract: An information processing apparatus includes an optical disk and a drive mechanism for rotating the disk. The disk comprises a disk-shaped body and an attractable portion at the central portion of the body. The attractable portion has an attractable member projecting from the body. A center hole, defining the center of rotation of the body, is cut in the attractable member. The drive mechanism includes a turntable which is rotated by a motor. A depression is formed in a support surface of the turntable. A magnetic attraction unit is arranged in the depression so as to magnetically attract the attractable portion, whereby the attractable member is housed in the depression and the surface of the body is in contact with the support surface.

Abstract: A disc data reproducing apparatus, including a rotating mechanism for rotating the disc about a central axis, an optical head disposed opposite the disc for receiving data from the disc, and a moving mechanism for moving the optical head along the radial direction of the disc. The optical head is disposed on one side of the central axis of the rotating mechanism and the moving mechanism is disposed on the other side of the central axis so as to reduce the space requirements for housing the head and moving mechanism within the apparatus.

Abstract: An apparatus for reproducing data from a data disc having a reproducing head opposite the data disc for processing data from the data disc. The apparatus includes a moving mechanism for moving the reproducing head between two radially separated positions along the radial direction of the data disc, and a locking device for automatically locking the reproducing head at one of the two positions for preventing movement of the reproducing head.

Abstract: An apparatus for loading a disc-containing cartridge into a reproducing device having a head, the cartridge including a window for exposing a portion of the disc, and a movable shutter for covering the window when the cartridge is removed from the apparatus. The apparatus including a main body having a port for receiving and discharging the cartridge therethrough, a cartridge moving mechanism for moving a cartridge inserted into the port to a prescribed position within the main body adjacent to the head, including a shutter opening mechanism, and a preventing mechanism for preventing the cartridge from moving to the prescribed position when the shutter is not fully opened by the opening mechanism for reducing damage to the head during loading.

Abstract: An optical disk comprising a disk-like body having two base plates made of synthetic resin and two recording layers formed on the base plates, respectively. The body is formed by bonding the base plates, with a spacer interposed therebetween, such that the recording layers face each other. The disk further comprises two centering members, each projecting from the surface of the center portion of one base plate. Each centering member is made of synthetic resin, and one magnetic member is mounted on the centering member. The centering member is inserted in a hole formed in the center portion of the body. The centering member has a center hole defining the center of rotation of the body, and also three projections formed in the surface thereof which faces away from the recording layer. The magnetic member has three engaging holes and is mounted on the centering member, with the projections of the centering member fitted in the engaging holes.

Abstract: An information memory medium adapted for processing information with a drive mechanism including a turntable which has a support surface and a magnetic attraction member. The information memory medium includes a disk-shaped body, and an attractable member and a label disposed on the body. The label represents a manufacturer, recording sides, and type of the disk, etc., and is located on a portion of the body other than the surface where the attractable member is disposed and other than where the support surface comes in contact with the body.

Abstract: An optical disk comprising a disk-like body having two base plates made of synthetic resin and two recording layers formed on the base plates, respectively. The body is formed by bonding the base plates, with a spacer interposed therebetween, such that the recording layers face each other. The disk further comprises two centering members, each projecting from the surface of the center portion of each base plate. Each centering member is made of synthetic resin, and one magnetic member is mounted on the centering member. The centering member is inserted in a hole formed in the center portion of the body. The centering member has a center hole defining the center of rotation of the body, and also a recess for holding the magnetic member. Four through-holes are formed in the bottom of the recess. The magnetic member has four projections and is held in the recess, with the projections inserted into the through-holes of the bottom of the recess.

Abstract: A cartridge loading apparatus is provided with a pair of locking devices for locking a cartridge received in a housing of the apparatus under a prescribed force. Each locking device includes a locking lever which is rotatable between a release position where the cartridge is set freely movable and a locking position where the locking lever engages a recess formed on each lateral side face of the cartridge, a reverse insertion prevention lever rotatable about the same shaft as the rotating shaft of the locking lever, a first spring for biasing the locking lever and the reverse insertion prevention lever to come close to each other, and a second spring for biasing the locking lever to the release position while the locking lever and reverse insertion prevention lever are biased to come close to each other. The locking lever is biased by the first spring from the release position to the locking position upon engagement between the reverse insertion prevention lever and the cartridge inserted in the housing.

Abstract: A cartridge for housing a disk-shaped information recording medium to be inserted in a recording and reproduction apparatus. The cartridge includes a first case for enclosing a first half of the disk and a second case for enclosing a second half of the disk. The first and second cases are movable into and out of contact with each other along a pair of disk support members. When the first and second cases are in contact with each other the disk is completely enclosed and protected from contamination. Upon insertion in the recording and reproduction apparatus, the first and second cases are automatically separated by a predetermined distance to expose a radial portion of the disk for recording and reproduction.

Abstract: A radiation-sensitive record disc is disclosed having a first disc and a second disc coaxially positioned adjacent the first disc to reinforce the first disc. A first spacer is positioned between the first and second discs for fixedly connecting the discs together and to form an air space between the discs. A recording layer is formed on one surface of the first or second discs within the air space. A second spacer is radially displaced from the first spacer, and positioned between the first and second discs. This second spacer enables the discs to move relative to each other in a radial direction in response to expansion or contraction of at least one of the discs due to changes in temperature, humiduty, atmospheric pressure, etc. In the preferred embodiment the first spacer comprises projections on the inner surface of the second disc, and the second spacer comprises an annular ring which slidably engages a projection on the outer peripheral surface of the second disc member.

Abstract: An optical disk with a recording layer formed on the inner surface of a protective plate has data which is read out upon irradiation of a laser beam. A substrate supports the protective plate such that the recording layer opposes the substrate and a space is formed therebetween. The spacer is sandwiched between the protective plate and the substrate so as to couple them. The spacer is an elastically deformable member. Therefore, when the protective plate expands or contracts relative to the substrate, due to deformation of the spacer, excessive force does not affect the recording medium. Warp, wave or damage to the disk due to expansion/contraction of the protective plate or substrate can be prevented, thereby allowing stable data processing.

Abstract: A radiation-sensitive record disc having a first substrate and a second substrate, coaxially positioned and spaced from the first substrate. The second substrate has an inner vent hole perpendicular to its surface which provides fluid communication between the space and the outer surface to the substrate. A pressure equilibrium housing is coaxially provided on the outer surface of the second substrate in communication with the vent hold. This housing has a recess on its inner surface adjacent the outer surface of the second substrate so as to form a cavity. An expansible membrane is provided in the cavity for receiving, through the vent hole, the internal pressure which exists in the air space. This cavity also contains an outer vent hole, on its outer surface, to provide equilibrium between the pressure within the air space and the surrounding air so as to absorb the change of intended pressure within the air space.