Thread cutter for sewing machine

A thread cutter for a sewing machine, which is provided on an underside of a needle plate having a needle hole and cuts a needle thread and a bobbin thread both located between a workpiece cloth and a rotary hook including an outer rotating hook and an inner bobbin case, the thread cutter comprising:

• a first thread seizing assembly which is supported so as to be reciprocally movable and includes two unit thread seizing members having distal ends provided with first thread seizing portions respectively, the first thread seizing assembly seizing the needle thread having passed the bobbin case and a bobbin thread by the first thread seizing portions, the bobbin case housing a bobbin on which a bobbin thread is wound, the bobbin thread extending from the bobbin to the needle hole of the needle plate;
• a cutting blade located nearer to the needle hole side than a movement locus of the first thread seizing assembly;
• a second thread seizing assembly which seizes the needle and bobbin threads both having been seized by the first thread seizing assembly during a backward movement of reciprocation of the first thread seizing assembly, cutting the needle and bobbin threads in cooperation with the cutting blade;
• and
• a drive unit which drives the first and second thread seizing assemblies, wherein when the needle and bobbin threads having been seized by the first thread seizing assembly are further seized by the second thread seizing assembly, the first thread seizing assembly is moved so that the distal ends of the unit thread seizing members are spaced from each other by a predetermined distance in a direction intersecting a movement direction of the first thread seizing assembly.