Patent ID: 8020502

Claim:
A thread cutting device of a sewing machine which is disposed below a throat plate having a needle hole through which a needle for carrying out a needle oscillating motion in an orthogonal direction to a cloth feeding direction penetrates and serves to cut at least one of a needle thread and a bobbin thread which are positioned between a horizontal shuttle and the needle hole, the thread cutting device comprising; a fixed blade; a first thread catching member having a first thread catching portion for catching a thread positioned between the horizontal shuttle and the needle hole and carrying out forward and backward movements below the throat plate while the first thread catching portion catches the thread; a second thread catching member having a second thread catching portion for catching the thread laid between the needle hole and the first thread catching portion and guiding the thread caught by the first thread catching member to the fixed blade and to cut the thread by the fixed blade; and an operating device for causing the second thread catching member to catch the thread and cut the thread caught by the first thread catching member, wherein the first thread catching member serves to carry out forward and backward movements in a needle oscillating direction, and the bobbin thread laid between the first thread catching member and the needle hole is changed to be parallel with the needle oscillating direction by the forward and backward movements, and wherein the second thread catching member serves to carry out the forward and backward movements to an approaching/separating position to/from a movement path of the first thread catching member on a path intersecting with the movement path of the first thread catching member.