Patent ID: 7918171
Filing Date: 2011-04-05
Classification: D05B

Abstract:
1. A threading device of a sewing machine, the sewing machine comprising a sewing machine main body, a needle through which a needle thread is inserted, and a spreader mechanism which interlaces a covering thread with the needle thread to form top covering stitches, wherein the spreader mechanism is attachable and detachable with respect to the sewing machine main body, the threading device comprising: a threading hook which moves forward to enter an eye of the needle to catch the needle thread, and moves rearward with the needle thread being caught to insert the needle thread through the eye; a threading shaft which holds the threading hook; an operating member which is operated to move the threading shaft; a threading operation mechanism which transmits a movement of the threading shaft to the threading hook to move the threading hook back and forth; and a restricting device which makes the threading operation mechanism inoperable when the spreader mechanism is attached to the sewing machine main body, and makes the threading operation mechanism operable when the spreader mechanism is detached from the sewing machine main body.