Method of and apparatus for winding all-thread bobbins

摘要

All-thread bobbins for use as sources of lower thread or underthread in sewing machines are formed by winding a thread onto a slender rotary spindle which extends across a winding chamber between and into aligned openings of two end walls which flank the chamber and at least one of which is adjustable axially of the spindle to vary the length of bobbins. The rotating spindle draws thread from a spool or from another suitable source of supply. When the bobbin in the chamber is fully grown, the spindle is extracted from the opening of one of the end walls and from the chamber and the distance between the end walls is increased to permit evacuation of the fully grown bobbin, e.g., by gravity. The thread between the source and the evacuated bobbin is engaged by tongs extendable into the chamber through the opening of the one end wall, and the thus engaged portion is looped and maintained in the opening of the one end wall in a position of readiness for engagement by and for winding around the spindle after the latter is again moved across the empty chamber and into the opening of the one end wall to proceed with the making of a next-following bobbin.