Apparatus for detecting upper thread

摘要

Problem: to accurately detect the upper thread passing through the bobbin case.The upper thread detecting apparatus is applied to a sewing machine equipped with a bobbin case.The upper thread detecting apparatus comprises a reflecting member disposed on one side of the cauldron, and an optical sensor disposed on the other side of the cauldron and irradiating the surface of the bobbin case to which the upper thread passes, detects the reflected light of the detected light reflected by the surface of the bobbin case and reflected by the reflecting member.The surface of the bobbin case includes a flat portion in which the detected light is irradiated.The optical axis of the detected light is inclined with respect to the flat portion.Diagram