| 摘要 |
A print hammer for printers and typewriters comprises a hammer rod (11) which is axially movable in a housing (17, 18). The hammer rod is biassed towards a rest position by a spring and can be moved to a print position by a drive means, for example a solenoid coil (19). The hammer rod delimits a room (31) in the housing the size of which increases during the movement of the hammer rod towards the print position. The room (31) is connected to the surrounding atmosphere via a narrow channel (33) and also via a valve means (25, 28) which is open during the movement to the print position but closed during the return movement to the rest position. The valve means (25, 28) also forms a stop member for the hammer rod (11) in the rest position. |
