Thread cutting mechanism of sewing machine

Abstract

The invention provides a thread cutting mechanism of a sewing machine, and belongs to the technical field of sewing machines. The thread cutting mechanism solves the problem that as for an existing thread cutting mechanism, thread residues are long after sewing threads are cut. The sewing machine comprises a base plate and a machine shell, a machine needle is arranged on the machine shell, and a lower shaft and a driving shaft are connected to the interior of the base plate in a rotary mode. The thread cutting mechanism comprises a movable cutter, a fixed cutter and a disc-shaped movable cutter frame. The movable cutter frame is fixed to the end of the lower shaft. The movable cutter is fixedly connected to the movable cutter frame. The driving shaft is connected with the movable cutter frame in a transmission mode and can drive the movable cutter frame to rotate. The fixed cutter is connected to the interior of the base plate in a sliding mode. A transmission structure capable of driving the fixed cutter to move and get close to the machine needle when the movable cutter frame rotates towards one side and enables the movable cutter to get close to the fixed cutter is arranged between the movable cutter frame and the fixed cutter. By means of the thread cutting mechanism of the sewing machine, the thread residues generated after cutting can be shorter, and thread cutting quality can be improved.

Description

technical field [0001] The invention belongs to the technical field of sewing machines, and relates to a thread trimming mechanism of a sewing machine. Background technique [0002] Most of the industrial sewing machines are general-purpose sewing machines, including lockstitch machines, chain stitch machines, quilting machines, overlock stitch machines and interlock stitch machines, among which lockstitch machines have the highest usage rate. With the continuous adjustment of the market and consumption structure, the medium and low-speed industrial sewing machines can no longer meet the production needs. The sewing machines are developing in the direction of high-speed and serialization. Electronic and computer technologies are widely used in sewing machines. The internal structure of the sewing machine is complex, including the presser foot lifter and the thread trimmer mechanism. [0003] For example, a Chinese invention patent application (application number: 2010106028...

AI Technical Summary

Problems solved by technology

The thread cutting device can realize the cutting of the suture, but the fixed knife does not move when the moving knife moves. In order to avoid cutting the suture by the fixed knife during the sewing process, usually the fixed knife needs to keep a certain distance from the needle , the distance is roughly 3 to 4 mm. When thread trimming is required, the moving knife moves to the fixed knife and cuts the suture at the fixed knife. After the suture is cut, the thread ends are located at the fixed knife, so the remaining thread ends on the fabric are longer

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