speed and the stitch length can be considerably increased in the embodiment of fig3 with the sewing machine 1 stopped and drive mechanism 52 switched on worm gear 53 drives inner sun wheel 55 through input e1 39 at a uniform speed due to the rotation of inner sun wheel 55 pinion 59 rolls on outer sun gear 65 which with swing drive mechanism 44 at rest also stands still and absorbs the reaction torque produced by the rolling motion of pinion 59 the rolling motion of pinion 59 drives pinion cage 57 and thereby shaft 66 carrying control cam plate 18 with control lever 67 at rest the uniform drive motion at input e1 39 results in an also uniform drive motion at output a 39 so that control cam plate 18 executes a continuous rotary movement to drive work clamp 2 with the sewing machine 1 switched on eccentric 45 of swing drive mechanism 44 imparts an oscillatory motion to control lever 67 and thereby to outer sun gear 65 in the first embodiment of the invention this oscillatory motion is superimposed by the continuous drive motion produced by drive mechanism 52 at the same time swing drive mechanism 44 is adjusted to the motion of needle bar 8 in a manner such that with needle 9 engaged in the workpiece the swing direction of outer sun gear 65 is opposite to the direction of rotation of pinion cage 57 whereby the drive motion of outer sun gear 64 is subtracted from the drive motion produced by drive mechanism 52 with needle 9 in a position above the workpiece on the contrary.