a slit or aperture 4 leading to the lower edge of the needle shank and a needle latch 5 is supported in the longitudinal slot 3 such that it pivots freely i e undamped about a latch pivot 6 the latch pivot 6 is formed by two bearing tangs 7 extending out of the side portions laterally defining the longitudinal slot 3 the needle latch 5 is supported on the bearing tang 7 by means of a pivot bore 8 the needle latch 5 has a spoon 9 on one end the spoon 9 just overlaps the tip of the needle hook 2 when it is in its closed position in the rear or open position it rests with seating surfaces embodied on wedge shaped convergent flanks of its spine on seating surfaces 10 adapted to the shape of its spine which are located in the region of the upper edge of the side faces of the needle shank 1 defining the longitudinal slot 3 the rear position and the closed position of the needle latch are shown in dashed lines in fig1 and 3 respectively in accordance with the invention the latch 5 in the region between the pivot bore 8 and the spool 9 is provided with at least one through opening or hole in all the forms of embodiment shown in the form of embodiment shown in fig1 a through hole 11 of elongated slit like shape is provided in the needle latch 5 in the region shown in the vicinity.