Abstract: A static eliminator comprises one pair of discharge electrodes. One electrode issues ions of a polarity while the other electrode issues ions of opposite polarity. In addition to the foregoing, polarity of ions issued from each of said discharge electrodes is switched over to opposite polarity. The switching over of polarities is synchronized with each other so that ions issued from each discharge electrodes are of opposite polarities. In another embodiment, static eliminator comprises a rotary ionizer or rotary ion issuing discharge electrodes. In still another embodiment, static eliminator comprises more than three arrayed discharge electrodes, each of discharge electrodes issues ions of opposite polarity to that issued from adjacent discharge electrodes.

Abstract: This invention enables one, or both, or none of position servo control and position lock control of a galvanomirror, to control a read beam to an optimum position under any of on-track state, seek state, position setting state after the completion of a seek operation, and positional deviation existing state between a write beam and the read beam. The invention locks the position of the galvanomirror when a unit is energized or retried, reads a galvanomirror position signal provided at this moment, finds an offset signal for zeroing the galvanomirror position signal, and adds the offset to the position locked galvanomirror during a seek operation with the write beam, thereby removing an offset of the galvanomirror position signal.

Abstract: A hollow platen roller common for reading and recording heads is provided. A cam shaft is disposed in the hollow platen roller and the cams are provided at the opposite ends of the hollow platen roller. The reading and recording heads are disposed in operation with the cam. Through the operation of the cam, the reading or recording head is selectively contacted with the outer surface of the hollow platen roller.

Abstract: A solenoid apparatus includes a core of magnetic material and a plunger of magnetic material movably mounted at one end of the core. A bobbin is disposed about the core and the plunger and an electric coil is wound thereon. A U-shaped yoke extends over one end of the core and is secured thereto. Opposite ends of the wire forming the coil are connected to first and second terminals, one of which is connected to the positive lead wire and the other of which is connected to the yoke, whereby the yoke acts as the ground connection.

Abstract: A solenoid assembly includes a coil bobbin having a pair of hooks extending in the longitudinal direction of the bobbin from a flange formed on one end of the bobbin and projecting radially outwardly from the axis of the bobbin at the ends thereof. A magnetic yoke having openings for receiving the hooks and a grommet having a base portion in contact with the magnetic yoke are seucred together by the hooks. The grommet has a neck portion extending in the axial direction of a magnetic core and a central opening for a lead wire to a coil on the bobbin. The magnetic yoke is fixed to one end of the magnetic core which is located in a central opening formed in the coil bobbin. A plastic casing is then molded about the entire assembly.