For controlling selection of needles, intermediate jacks or pattern jacks in a circular knitting machine there is provided a stepwise advanced pattern drum (5) selectively acting on selection slides (3) which interfere with butts of needles, intermediate jacks or pattern jacks.
The drum (5) is advanced by a pawl (10) pivoted to a rocking lever (11) controlled by a cam (12) the axis whereof is different from the axis of the needle cylinder (1). The cam (12) is rotated at a speed timed to that of the needle cylinder (1). The cam (12) has two different profiles (12a, 12b) at different heights for acting on said lever (11) and may be provided with additional superposed profiles (21) for action on the selection slides (3) through respective three-arm levers (8).