12.
    发明专利
    未知

    公开(公告)号:DE1943675A1

    公开(公告)日:1970-05-06

    申请号:DE1943675

    申请日:1969-08-28

    Applicant: IBM

    Abstract: 1,273,614. Selective printing. INTERNATIONAL BUISNESS MACHINES CORP. 10 Sept., 1969 [2 Oct., 1968], No. 44599/69. Heading B6F. Wire printers.-A screen-wire print head 9, supported on a frame member 21 which is moved by threaded shaft 17 along the printing line, comprises seven armatures 32 supported on leaf springs 34 which bias attached print wires 10 into printing position, a common electromagnet 36 which holds all armatures in retracted position, and seven individually selected electromagnets 37 which when actuated set up a counter flux and allow the leaf springs 34 to effect impression. The armatures 32 are in side-sliding engageengagement with faces 30 of one polepiece and move in a direction towards and away from the faces 29 of the magnetic cores. This sliding magnetic contact effects as a damper. The selection electromagnets 37 have two windings 37b, 37t, one winding is in series with a condenser 38 and shunted by a resistor 40. When a switch 39 is operated the flux in both windings allows the leaf spring to be released from the flux of the common magnet 36. The changing of the condenser reduces the flow through the coil and after the switch 39 is opened the condenser 38 discharges through the resistor 40 and the flux generated helps the magnet 36 to quickly restore the armature 32.

Patent Agency Ranking