Sewing machine

Abstract

A sewing machine is capable of fixing sewing distance at a higher precision. The sewing machine includes a sewing machine motor serving as a drive source for driving the vertical movement of a needle bar, a control part for controlling the sewing machine motor such that a sewing pitch coincides with a set value, and imaging part for imaging a seam formed in a workpiece at a needle drop position. The control part obtains the length of the most recent seam from an image of the most recent seam imaged by the imaging part and also compares the length of the most recent seam with the set value of the sewing pitch to thereby correct the number of rotations of the sewing machine motor.

Description

technical field [0001] The present invention relates to a sewing machine for sewing with a fixed sewing pitch. Background technique [0002] At present, there is known a sewing machine that uses an optical element fixedly equipped on the frame of the sewing machine to photograph the object to be sewn on the needle plate, and obtains the movement amount of the object to be sewn based on the photographed data. The sewing pitch is maintained at a set value by controlling the needle entry with a fixed amount of movement (for example, refer to Patent Documents 1 and 2). [0003] Patent Document 1: Japanese Patent No. 4724938 [0004] Patent Document 2: Japanese PCT Publication No. 2006-517449 [0005] However, the above-mentioned conventional sewing machine obtains the moving amount of the object to be sewn, and controls the sewing machine motor so that the needle drops after moving the set sewing pitch. Even if there is an error in the trace with respect to the set sewing pit...

AI Technical Summary

Problems solved by technology

[0005] However, the above-mentioned conventional sewing machine obtains the moving amount of the object to be sewn, and controls the sewing machine motor so that the needle drops after moving the set sewing pitch. If there is an error in the trace relative to the set sewing pitch, it cannot be corrected, and it is possible to continue sewing in the event of an error.