Abstract: A chopping secondary mirror system is provided, in which magnetic circuits of a driving motor for causing a secondary mirror to chop about its rotation axis are mounted to the secondary mirror via a driving motor mounting so that the magnetic circuits function as a balancing mass to position the center of gravity of a whole chopping section on said rotation axis. The driving motor mounting is secured to the secondary mirror at the center of the secondary mirror. Leaf springs are used as vibration damping springs of a reaction force compensator.

Abstract: An electromagnetic drive actuator including a magnetic circuit comprising at least one yoke having plate-shaped, L-shaped, E-shaped cross section or the like, at least one magnet mounted on the yoke and a magnetic flux extending from the magnet to the yoke, at least one coil arranged so as to cross the magnetic flux and produce a drive force in a direction crossing a plane including the magnetic path of the magnetic circuit when current is applied to the coil, and at least one magnetic shield member provided at the side portion of the coil to thereby prevent a counter drive force from being produced in a direction opposite to a desired direction of a drive force produced by the coil.

Abstract: A carriage assembly for use with an optical recording disc for optical recording and reproduction relative to the disc comprises a frame, an optical lens for projecting and receiving a light beam for the optical recording and reproduction, a carriage movably supported in the frame for supporting the optical lens relative to the disc, a vertical guide arrangement for permitting a movement of the optical lens relative to the carriage in a vertical direction relative the disc surface, a vertical drive arrangement for driving the optical lens in the vertical direction relative to the carriage, a radial guide arrangement for permitting said carriage to move in a radial direction of said optical disc, and a radial drive arrangement for driving the carriage in the radial direction of the disc.

Abstract: A carriage assembly for a disc operating apparatus comprising a frame, a carriage movably supported in the frame relative to the disc, an optical lens or magnetic head mounted on the carriage for recording and reproducing information on the disc, and a radial guide arrangement permitting movement of the carriage in a radial direction relative to the disc. The assembly also comprises a radial drive arrangement including an electromagnetic coil mounted to the carriage and a permanent magnet mounted to the frame. The permanent magnet is electromagnetically coupled with the electromagnetic coil for driving the carriage in the radial direction of the disc. The electromagnetic coil includes two sections which sandwich the carriage and are shaped to come into contact with each other at both sides thereof, whereby the cross section of the electromagnetic coil is hexagonal in a plane parallel to a surface of the disc. As a result, the dimensions in the radial direction of the carriage assembly are decreased.

Abstract: A carriage of a head positioning assembly is disposed along an edge of a magnetic disc so as not to come in contact with the magnetic disc, whereby the length of the winding bobbin of the voice coil can be elongated, so that a driving force generated in the elongated winding bobbin causes a magnetic read and write head to rapidly move to a position over an objective track on the magnetic disc.

Abstract: A transducer carriage 1 is slidably mounted on and between parallel guide rails 2a, 2b by two spaced pairs of inclined bearing rollers 3a, 4a, 3b, 4b, on one side and a single intermediate pair of such rollers 3c, 4c on the other side. The lower intermediate roller 4c is elastically mounted to the carriage by a rubber shaft ring 9 and exerts a biasing force on its guide rail, to thereby maintain the remaining fixedly mounted rollers in stable contact with their associated rails.

Abstract: An improved carriage assembly for linearly reciprocating a data converter pickup or the like. Magnetic circuits are provided on each side of a carriage, and a driving coil wound on a transversely solid type coil bobbin which surrounds the carriage, is magnetically linked with the two magnetic circuits. Guide rails are provided between the carriage and the two magnetic circuits. The moving elements including the carriage, the driving coil, and the bobbin are supported on the guide rails for linear movement therealong by rollers.