| 摘要 |
<p>An impact printer such as a typewriter, of the kind wherein the printing surface is impacted by the type face (14A) through an impregnated ribbon (16) under the drive of a hammer (18), wherein a rebound mechanism (20) is provided to absorb the kinetic energy present in the hammer when it rebounds after imprint, this mechanism comprising a pivotted rebound arm (22) driving a ratchet device (28, 30) which is coupled to a ribbon feed wheel (32) in order to increment the ribbon. The rebound mechanism may alternatively be operated by rebound energy derived from a prime mover which actuates another movable part of the printer, such as a carriage escapement mechanism, with an impulse drive. The invention is especially aimed at a low cost printer adapted for battery operation, and enables the use of a separate actuator for ribbon increment to be avoided.</p> |
