Cloth-feeding device of sewing machine

Abstract

The present invention provides a fabric feeding apparatus of sewing machine capable of providing approximately same distance of sewing. The fabric feeding apparatus of sewing machine comprises a fabric frame (S), which moves synchronously with a needle bar (4) moving up and down driven by a motor of the sewing machine, and feeds fabric on a needle plate (2) by feeding tooth; a fabric feeding quantity input apparatus, which inputs fabric feeding quantity based on the fabric frame (S); a drive control apparatus (70), which measures fabric thickness fed by the fabric frame (S); a storing apparatus, which stores fabric feeding quantity translation table of relationship between fabric thickness and fabric feeding quantity suiting for the fabric thickness; and a fabric feeding quantity correction apparatus, which selects the fabric feeding quantity corresponding with fabric thickness measured by the drive control apparatus (70) from the fabric feeding quantity translation table and corrects the data of fabric feeding quantity with the fabric feeding quantity input apparatus such that the fabric feeding quantity is that selected.

Description

technical field [0001] The present invention relates to a cloth feeding device of a sewing machine such as a needle feeding sewing machine or a combined feeding sewing machine having a needle feeding function of moving a cloth by oscillating a needle. Background technique [0002] As the above-mentioned combined feed sewing machine, there is known, for example, a sewing machine described in JP-A-7-136363. Referring to FIGS. 6 and 7 to describe a conventional combined feed sewing machine, the main shaft 101 is connected to a sewing machine motor (not shown) that serves as a driving source for sewing, and is driven to rotate around the axis by the sewing machine motor. A feed cam 102 composed of an eccentric cam is provided on the main shaft 101. A rod 103 that swings up and down by the rotation of the feed cam 102 is connected to the feed cam 102. The needle 125 and the upper feed leg 126 swing the lever 104 in the horizontal direction, and the lever 127 swings the lower fee...

AI Technical Summary

Problems solved by technology

This difference is the difference in the horizontal position of the pierced cloth, which will cause a situation that does not match the cloth feeding amount set by the turntable 119.

Especially in the case where the thickness of the fabric is obviously different in a series of sewing (such as the shoulder pad sewing of a suit), it will lead to the difference in the sewing spacing in one process, which will reduce the quality of the sewing product

[0007] As a solution to such a problem in needle feeding, there is a method of using a triangular cam to form the cloth feeding cam 102, so that the trajectory of the needle tip can be approximated to a rectangle, thereby preventing the difference in the distance between sewing due to the influence of the thickness of the cloth. method, but there are problems such as large acceleration and deceleration on the mechanism, inability to increase the speed, and increased noise and vibration

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