Intermittent motion mechanism

Claim 1

An intermittent motion mechanism comprising: a first rotary ratchet wheel having disposed therearound a first set of ratchet teeth and having an intervening tooth space between each two successive ratchet teeth; a second rotary ratchet wheel having disposed therearound a second set of ratchet teeth and having an intervening tooth space between each two successive ratchet teeth, at least one of said tooth spaces being deeper than the remaining tooth spaces; means mounting said first and second ratchet wheels in side-by-side relationship for rotational movement independently of each other and mounting said first and second ratchet wheels in mutually relative positions so that said second ratchet wheel may be cyclically moved into an actuating position wherein the deeper tooth space is in alignment with one of the tooth spaces between successive ratchet teeth of said first ratchet wheel; means reciprocable into engagement with said second set of ratchet teeth to effect intermittent angular movement of said second ratchet wheel through a plurality of angular increments to cyclically advance same to said actuating position and reciprocable into concurrent engagement with both said first and second sets of ratchet teeth when said second ratchet wheel is in said actuating position to effect intermittent angular movement of both ratchet wheels through one angular increment; whereby said first and second ratchet wheels are intermittently rotated in a stepwise manner at different rates, and said last-mentioned means comprising a pair of feeding pawls one of which engages only with said first set of ratchet teeth and the other of which engages with both said first and second sets of ratchet teeth.