Sewing machine thread changer raises work rate, saves costs and space

摘要

A first general apparatus for changing sewing machine needle thread has: a first holder (6) to secure thread sections (401a, 402a, 403a, 404a, 405a) drawn from respective reels (401, 402, 403, 404, 405); cutting device (114) for a thread just processed by the machine, selectively drawn from the first holder and to be changed; second holder (115) to secure this thread cut end running to the machine needle side; device for selecting a thread for use from those in the first holder; device (12) to move the selected thread end to a given knotting point and; knotting device (9) to join, at the knotting point, the selected thread end to the end section of the processed thread, held by the second holder, to be changed. Also claimed is a second particular apparatus having: a sewing machine (2) and needle (204); reels of thread and a first holder as above securing parallel threads hanging from the reels; a device to select one thread by moving the first holder at right angles to the thread d paths; a cutter arm (A, 11) located along the thread paths nearer the needle than the selector and moveable to an operating position by crossing the path of the processed thread, grasping it, and back to a retracted position to cut the thread and hold the end running towards the needle; a receptor arm (B, 12) which grips the new thread to be used by crossing its path to an operating position and draws it back to a retracted position to hold its end firmly at a pre-determined distance from the old end held by the cutter arm and; a knotting unit (9) which advances parallel to the threads from a rest position to an operating position between the threads held by the cutter and receptor arms to join the two threads, from where it retracts to the rest position.