Blind stitch sewing head, e.g. for carbon fiber mats, includes rotary gripper hook and curved needle swinging with parallel axes and assisted by a loop spreader

摘要

A blind sewing head producing a single thread (100) chain stitch has a curved needle (32) and a rotary gripper hook (44) swinging about parallel axes. The thread loop (98) is picked up by the point (48) of the hook and the needle passes through a slot in the hook (44). A spreader (52) reciprocates parallel to the axes to keep the thread under tension for the next stitch. The sewing head can be mounted at the end of a robotic arm. The needle is supported by a grooved roller (34) when entering the fabric and by a guide (42) on the concave side when emerging in order to prevent needle distortion, especially with stiff and heavy fabrics. The height of the presser foot (60) is adjustable.