Patent ID: 6814018
Filing Date: 2004-11-09
Classification: D05B

Abstract:
An automatic thread cutting apparatus for sewing machines to cut off yarns and hold the remaining portion of the yarns after sewing operation is completed for use in successive operations, comprising:a thread cutter including a cutting blade and fixed blades located on a top section of a sewing deck of a sewing machine, said fixed blades including a upper fixed blade and a lower fixed blade that are stacked over each other to form a gap therebetween to allow said cutting blade to pass through for cutting off the yarns, said cutting blade having a first cutting section for cutting off the yarns and a second cutting section to couple with said fixed blades to hold the remaining portion of the yarns; a linkage mechanism including a direction switch section, a first crank lever, a second crank lever, a first linkage bar and a second linkage bar, the direction switch section having one end connecting to one end of said first crank lever, said first crank lever being connected to said second crank lever, said second crank lever being connected to said first linkage bar, said first linkage bar being connected to said second linkage bar, said second linkage bar being connected to said cutting blade; and a driver mounted onto a bracing section having a moving section coupling with the directing switch section of said linkage mechanism for driving said linkage mechanism to move reciprocally and driving said thread cutter to cut off the yarns.