| 摘要 |
A print head for a matrix printer, comprising a plurality of reciprocatable needles (19), a core (14) surrounded by a coil (16) associated with each needle, a yoke (12) connected magnetically to each core (14), an armature (17) associated with each core (14), and operatively connected with the needle, pivot means (13,18) about which the armature rocks to move the needle between a non print and a print position, and first spring means (23) biasing the armature and needle operatively connected there to a non print position, characterised in that second spring means (24) is provided to act to oppose partly the biasing force of the first spring means and to urge the armature towards the yoke (12) with a torque lower than the torque exerted by the first spring means.
|
