Automatic non-bobbin lower thread-supplying apparatus for industrial sewing machine

Abstract

An automatic non-bobbin lower thread-supplying apparatus for industrial sewing machine is introduced to resolve a limited lower thread-supply problem on a conventional bobbin of hook, which the problem will lead to frequent work on replacing the bobbin during a sewing operation and obviously is both time-consuming and quality-reducing. In the present invention, the conventional bobbin is abandoned by providing a throughout center aperture to a lower shaft that drives the hook. The center aperture forms a passage for the lower thread from a center hole of a transmission gear at one end of the lower shaft to the center of hook at another end thereof. By providing the center aperture of the lower shaft, the lower thread can be introduced from outsides of the sewing machine and directly supplied to the hook without frequently replacing the bobbin during the sewing operation.

I claim:  
     
         1 . An automatic non-bobbin lower thread-supplying apparatus for industrial sewing machine, characterized in that a throughout center aperture for allowing a thread to pass therebythrough is provided to a lower shaft of the sewing machine, in which the center aperture connects a center of a hook of the sewing machine with a center hole of a transmission gear of the sewing machine.