Tack-in selvage forming apparatus

摘要

A tack-in selvage forming apparatus for tacking in the end portion of a picked weft yarn to form a selvage structure in weaving a towel. The tack-in selvage forming apapratus is comprised of a tack-in needle which is controllably driven by a driving mechanism including a cylindrical grooved cam rotatable in timed relation to a main shaft of a loom. The grooved cam is formed at its periphery with generally annular shallow and deep cam grooves. The shallow cam groove is parallel with a plane perpendicular to the axis of the grooved cam, while the deep cam groove is curved relative to the same plane. A part of the shallow cam groove and a part of the deep cam groove is common and the same in depth. The shallow cam groove has a profile corresponding to a resting state of the tack-in needle, while the deep cam groove has a profile corresponding to a tack-in operational state of the tack-in needle. A cam follower drivingly connected to the tack-in needle is selectively put into the shallow and deep cam grooves. Thus, the tack-in needle is rested when the cam follower is in the shallow cam groove and operated to accomplish tack-in of a weft yarn end portion when the cam follower is in the deep cam groove.