Abstract: A method of marking materials, wherein the surface of a marking material and the surface of a material to be marked are matched, a laser beam is applied to the marking material while scanning the beam to form a mark, the material to be marked consisting a transparent body on which a pattern of a character or the like is formed. The method for marking comprises a first step of applying the laser beam to the marking material with the first laser power to evaporate the marking material and make them deposit to a predetermined part of the material to be marked, a second step of applying a laser beam to the deposited matter on the material to be marked with a second laser power to remove or transform the deposited mater. Steel or stainless steel is used as the marking materials.

Abstract: A print unit provided with one or a multi-serial heads having a plurality of print pins widely arranged in a direction of the feeding of paper and is provided laterally movably on a guide shaft. A cassette holder having a plurality of monochromatic ribbon cassettes that are juxtaposed and received therein is arranged in parallel with and close to the moving path of the print unit. A suitable one of the monochromatic ribbon cassettes is transferred, in response to a control signal, from the cassette holder to the print unit, and from the print unit to the cassette holder.

Abstract: A mounting bed integral with a hammer bank is disposed parallel to a counter balancer composed of a counter balancer constituting member and a yoke. The mounting bed and the yoke are provided with solenoid coils opposed to a permanent magnet provided on the frame, and a pair of bearings are arranged between the mounting bed and the counter balancer constituting member. A position sensor for the mounting bed and the counter balancer is provided. A controller is provided to control a current and direction of the solenoid coil by a detection signal from the position sensor. The mounting bed integral with the hammer bank and the counter balancer are shuttle-operated in opposite directions by the controller.

Abstract: An impact dot line printer has a hammer bank equipped with a plurality of printing heads along printing lines mounted on the upper side of a belt extended between a pair of rotational drums. A counter balancer is mounted on the lower side thereof, the hammer bank and the counter balancer being reciprocated in the directions reverse to each other. Since repelling springs are provided on both left and right sides in order to reduce thrust required for deceleration at the end of shuttling operation of the hammer bank and the counter balancer, vibrations or noises caused by the collisions with the spring might occur. But by the present invention, rotors are provided with eccentric weights which act so as to offset force couple at the time of the collisions with the repelling springs, whereby the shock force caused by the collisions is sharply decreased to suppress the vibrations or noises.

Abstract: A write data compensation system compensates original write data which is recorded on recording disc mediums, the original write data to eventually be reproduced using a disc drive apparatus capable of reproducing data from recording media having differing recording densities. In the event that the write data is to be recorded on a low density recording media, the original write data is corrected by displacing each bit for which a bit shift is estimated to occur during reproduction in a direction coincident with a direction of the estimated bit shift. In the event that the write data is to be recorded on a higher density recording media, the original write data is corrected by displacing each bit for which a bit shift is estimated to occur in a direction opposing the direction of the estimated bit shift.

Abstract: An apparatus is provided for reproducing information recorded on a magnetic recording media. The recorded information is detected and amplified by a magnetic head device and a corresponding amplified detection signal is output therefrom. The amplified detection signal is input to a differentiator and to a non-ideal integrator. The outputs of the differentiator and the non-ideal integrator are subtracted from each other and the thus subtracted signal is applied to a zero crossing point detector. Pulses are generated representing the recorded information at each zero crossing point deteted by the zero crossing point detector. Since the non-ideal integrator does not effect integration of DC and low frequency signals, a compensating device is provided for generating a corresponding DC and low frequency signal and for adding this signal to the output signal of the non-ideal integrator.

Abstract: A spring-charge type printing head has an elongatable support including a piezoelectric element provided between an attracting permanent magnet and a hammer-fixing portion. Accordingly, the printing head can be operated at a high speed and require less power than a conventional device.

Abstract: A collet device for engagement with a spindle hub for clamping a flexible disk between the collet device and the hub, the collet device having a collet having a plurality of radially extending petal-like portions therearound, a collet shaft on which the collet is mounted, a regulating body on the collet and having stops thereon extending outside the ends of the petal-like portions and engagable by the ends of the petal-like portions for limiting the outward movement of the petal-like portions during an increase in the diameter of the collet, and an enlarging spring on the regulating body have legs thereon engaging the ends of the petal-like portions for urging the ends of the petal-like portions outwardly for increasing the diameter of the collet.

Abstract: There is provided a magnetic head used for both magnetic recording and reproduction thereof, comprising a magnetic head body with a gap portion, wherein a first material having a larger saturated magnetic flux density than that of said body is applied to one or both sides of said gap portion, said gap being internally provided with a second material having a smaller saturated magnetic flux density than said body.

Abstract: A line printer having a suitable number of hammers which are controlled by electromagnets and which are juxtaposed with equal pitch on a carriage to effect printing while simultaneously shifting the hammers, wherein adjacent hammers are not simultaneously driven to thereby prevent malfunctions due to the influence of adjacent electromagnets.

Abstract: A permanent magnet type printing head for an impact dot printer wherein a plate spring hammer has a hammer tip provided on one side thereof, and an attracting magnetic pole provided with a releasing electromagnetic coil arranged on the side opposite said hammer, wherein an armature is provided on the upper surface of the plate spring hammer instead of providing same on the same side of a magnetic pole, and wherein an arm of a yoke constituting a main magnetic path is provided on the plate spring hammer, and the magnetic pole is positioned between the hammer tip and the armature.