Control device for striper units in circular knitting machines

A control device for striper units in a circular knitting machine having at least one rotatable needle cylinder and at least one thread feed comprising a plurality of thread fingers, the device comprising a plurality of first cam disks each corresponding to one of said thread fingers, a common shaft for supporting said first cam disks, control levers each having cam follower means constantly engaging a respective one of first cam disks and each operatively connected to a corresponding one of said thread fingers to control said corresponding one of said thread fingers between an operative thread feeding position and an inoperative thread withdrawing position, a plurality of actuating members each rigid with a corresponding one of said first cam disks, said first cam disks and said actuaing members being axially non-displaceable on said common shaft, a plurality of revolvable actuator elements each in constant engagement with a respective one of said actuating members, a rotatable drive shaft for idly supporting said actuator elements, said drive shaft being rotatable at a rotational speed bearing a predetermined speed ratio to the rotational speed of said at least one rotatable needle cylinder, and means for selectively coupling said actuator elements with, and uncoupling from, said drive shaft for predetermined time lapses wherein the respective of said thread fingers are displaced between said operative thread feeding position and said inoperative thread withdrawing position according to a machine knitting program.