| 摘要 |
PURPOSE: To lower the impact sound with a stopper, by mounting a means calculating the moving speed of a hammer and reducing the returning speed of the hammer to the stopper. CONSTITUTION: A slit plate 11 provided with slits 110-113 is mounted to a hammer 101 and, when the hammer 101 reciprocates once, an output signal 20 is inputted to a control part 100 from a sensor 12. When the printing of a type having a wide printing area such as '' is designated, the large hammer current shown by a numeral 41 is made to flow to excite the hammer 101. By this method, a steep rising wave form is obtained as shown by a wave form 40. On the basis of the passing time 42 between the slits 112, 111 when the hammer 101 reaches a printing position and subsequently returns, the return speed of the hammer 101 is calculated. When the edge of the slit 111 is detected at a time T1, the re-excitation of the hammer 101 is performed after a time t1 by a pulse 43 and the returning speed of the hammer 101 is reduced to reduce the impact force when the hammer 101 returns to a stopper 8-1 at a time 44 and noise is reduced. |
