accordingly in clockwise direction in fig1 this causes the control lever 8a 8b to be swiveled to the position indicated by the dotted lines in fig1 in this way not only is control roll 11 moved out of the path of motion of the disengaging lever 12 but also the bolt 20 presses through arm 17b of pawl 17 the catch arm 17a out of its engagement with notch 19 of the needle bar 10 when the driver 13 which carries the now released disengaging lever 12 with the spring loaded pin 15b is flush with hole 10a of the released needle bar 10 the driver 13 is positively coupled with the needle bar 10 if the skipped stitch mechanism is to be switched off the lever arm 3b is lifted to the higher section of the cam 4a by means of the control knob 4b thereby preventing the sensing arm 3a from sinking into the depressed portion of the program cam plate 2 which causes the release of the needle bar thus in summary the skipped stitch mechanism is controlled by means of a program cam plate 2 via levers 3a 6 8a and 6b it has a coupling device which by means of a control lever 8a 8b can be engaged with and released from the needle bar 10.