A pressing rod mechanism and sewing machine

Abstract

The present invention provides a pressing bar mechanism and a sewing machine. The pressing bar mechanism includes, from top to bottom, a pillar installed in a casing of the sewing machine, an elastic assembly, and a pressing bar. The elastic assembly includes an upper compression spring, a balance weight and a lower compression spring. The upper and lower ends of the upper compression spring abut against the pillar and the balance weight respectively, and the upper and lower ends of the lower compression spring abut against the balance weight and the pressure bar respectively. In the present application, when the presser foot height changes to drive the pressure bar to move up, the lower compression spring is squeezed. For the balance weight in the elastic assembly, the elastic force exerted by the upper compression spring is smaller than the elastic force exerted by the lower compression spring, thereby promoting The balance weight moves up automatically to re-balance the force; the upward movement of the balance weight reduces the elastic force of the lower compression spring, that is, reduces the elastic force exerted by the lower compression spring on the pressing rod, so the force exerted by the elastic component on the presser foot The change is small, so that to a certain extent, the problems of unsightly stitches and staggered layers of sewing materials can be improved when sewing thicker fabrics and stems on fabrics, and the sewing quality can be improved.

Description

technical field [0001] The invention relates to a sewing machine, in particular to a pressing bar mechanism for the sewing machine. Background technique [0002] At present, all sewing machines are equipped with a pressing bar mechanism, such as a sewing machine pressing bar mechanism disclosed in the Chinese invention patent application with application number 201710353246.0. Generally speaking, the pressing bar mechanism includes a pressing bar and a presser foot arm that cooperate with each other, and a compression spring acting on the pressing bar. It can move up and down with the presser foot, and the pressure spring exerts pressure on the pressure rod, thereby providing the pressure required by the presser foot in the presser foot assembly. Furthermore, when the presser foot is lifted, the presser rod moves up with the presser foot, compressing the compression spring, the elastic force of the compression spring becomes larger, and the pressure fed back to the presser ...

AI Technical Summary

Problems solved by technology

Therefore, when the sewing machine with the above-mentioned pressing rod mechanism is sewing, the height of the presser foot will change with the thickness of the cloth, so that the pressure of the stage spring will also change accordingly; At the stalk part, the height of the presser foot moving up is relatively large, which causes the pressure of the presser foot to change too much. At this time, it is easy to cause the sewing material to be misaligned, and the stitch pitch becomes dense when sewing the stalk material, even when the electromagnet is used as the presser foot lifter. In the sewing machine of the driving source, after a long time, it is easy to cause the electromagnet to lift weakly

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