absorbed these forces do not produce any effect on crank 25 nor on the farther component parts of the transmission so that no risk of overstressing is incurred in the embodiment of fig5 with the stitch setting device a stitch length zero is set if stop discs 123 124 are at a minimum possible distance from each other and apply against contacting piece 127 from both sides to set a feed setting wheel 28 is turned so that stop discs 123 124 move apart from each other if forward sewing is desired the upper side of disc 112 is exposed to compressed air so that stop disc 123 comes to apply against contacting piece 127 by turning the setting wheel piston 112 loaded with compressed air is displaced and through piston rod 113 and link 131 crank 25 is pivoted as already mentioned in connection with the first embodiment a pivotal motion of crank 25 produces the effect of adjusting the feed step of feed dog 8 by turning setting wheel 25 clockwise or counterclockwise the distance of stop discs 123 124 from their zero position and thereby the feed step of feed dog 8 determining the stitch length are reduced or increased the impact forces.