Segment gear 1 and gear 2 rotate about fixed axes A and B. When driving segment gear 1 rotates continuously counterclockwise, gear 2 rotates until it comes into engagement with gear sector 3 which swings freely about axis A. At this spring a is stretched and gear 2 has a long dwell until the side of sector 3 strikes side b of segment gear 1. As soon as sector 3 is released by gear 2, spring a draws it back to its initial position.
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