of the striper 1 which in turn is driven by levers 6 from a knuckle joint as shown in fig1 the apparatus comprises a feed mechanism 7 object of the invention which as shown in fig2 and 3 comprises a set of toothed driving rollers 8 and a further set of driven rollers 9 mounted on respective parallel drive and driven shafts 10 and 11 said rollers mesh with one another without making any contact only for the purpose of pulling the yarn along by the alternate friction effect as the yarn passes between the teeth the rollers of each set are spaced apart and each pair of rollers 8 9 of each set defines an operating space s the face of the roller 8 9 facing the operating space s being provided with a bevelled surface 8a 9a the function of the bevelled surface 8a 9a of the toothed driving roller 8 9 is merely to facilitate the passage of the yarn from the neutral or inoperative area to the operating space wherein the rollers pick up the yarn and deliver it at a constant speed to the needles to drive the rollers 8 9 of the feed device there is provided a drive pulley 12 mounted on a shaft 13 carrying a bevel gear 14 meshing with a further bevel gear 15.