Patent ID: 10472753

Abstract:
A bobbin thread winder of a sewing machine including a bobbin winder spindle holding a bobbin and a driving mechanism to apply a drive force to the bobbin winder spindle, comprises a time measuring unit to measure an bobbin-thread winding execution time with respect to the bobbin, and a bobbin-thread winding amount calculating unit which calculates a winding amount of the bobbin based on the bobbin-thread winding execution time with respect to the bobbin measured by the time measuring unit. In the bobbin thread winder, since the bobbin-thread winding execution time was measured by the time measuring unit, and the bobbin winding amount of the bobbin is calculated based on the bobbin-thread winding execution time by the bobbin-thread winding amount calculating unit, it is possible to detect the bobbin winding amount of the bobbin accurately regardless of the type and thickness of the bobbin thread.