Patent ID: 8997669
Filing Date: 2015-04-07
Classification: D05B

Abstract:
1. A thread tensioner for a sewing machine, the thread tensioner comprising: a first disk; a second disk positioned next to the first disk; a spring configured to apply tension to a thread that is positioned between the first disk and the second disk by exerting a force against the second disk, the spring defining a first end, a second end, and a length between the first end and the second end, the spring being coupled to a rod extending from the second end of the spring; a knob configured, when rotated in a first direction, to travel along a threaded shaft toward the spring and thereby cause the length of the spring to shorten, the knob further configured, when rotated in a second direction, to travel along the threaded shaft away from the spring and thereby allow the length of the spring to lengthen; and a sensor configured to track a current length of the spring by tracking the position of the rod.