| 摘要 |
<p>A number wheel counter has a worm wheel (12) connected with the least significant number wheel. A worm gear (14) engaged with the worm wheel is mounted for both rotational and translational movement about a spindle (16). Cam means are provided such that as the worm gear rotated, it is also displaced bodily by the cam means so that the worm wheel remains unmoved. At the end of a defined travel of the cam means, the worm gear is returned rapidly to a rest position driving the worm wheel in the manner of a rack and pinion. In this way the number wheels are driven intermittently with the time interval during which the number wheels are between discrete number positions being minimised.</p> |
