JPS5939991Y2 - Sewing machine pleating device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a pleating device for a sewing machine in which an upper feed dog and a lower feed dog cooperate to feed cloth.

Conventionally, for example, in an overlock sewing machine equipped with upper and lower feed dogs, when performing pleat stitching in which the upper fabric is pleated while being sewn to the lower fabric, a separator is placed on the upper surface of the throat plate 1 as shown in Figure 1. Cloth W layered vertically by plate 3
,, Separate W2, make the feed pitch of the upper feed dog 4 larger than the lower feed dog (as shown), bend the fabric W2 inward of the escape hole 2a provided in the presser foot 2, and create the pleats G. I'm trying to form it.

Now, since the pleats G of the upper fabric W2 are folded, the thickness increases, and therefore the presser foot 2 has a higher thickness than when pressing the fabric W2 which does not have pleats G, as shown in FIG. As shown in the figure, the increase in the thickness of this cloth W2 causes it to be pushed E.

Therefore, in the lower part A of the presser foot 2 where one fold G is not formed, a gap is created between the cloth W2 and the lower end of the presser foot 2, and no pressing force is applied, so the upper feed dog 4
When the cloth W rises, the cloth W drawn by the upper feed dog 4
The force to support the bending of the bent portion G1 of No. 2 is lost, and the cloth W2 moves backward in the cloth feeding direction (to the right in Fig. 1), and the protrusion of the bent portion G1 becomes gentle as shown by the two-dot chain line in Fig. 2. There was a drawback that the finished pleats G were incomplete with shallow folds.

The purpose of this invention is to eliminate the above-mentioned conventional drawbacks with a simple configuration.

Hereinafter, the same numbers will be assigned to the same configurations as the above conventional one, and an embodiment of this invention will be explained with reference to FIGS. 3 to 6. 5b is raised upward to form an inclined surface 5a.

The other end of the plate body 5 is fixed on the separating plate 3 so that one end 5b thereof faces the edge of the relief hole 2a of the presser foot 2 on this side in the cloth feeding direction.

In such a configuration, the separation plate 3 and the plate body 5 separate the upper and lower cloths W1. When sewing is started by making the feed pitch of the upper feed dog 4 larger than the feed pitch of the lower feed dog while separating W2, the upper cloth (referred to as the upper cloth) W2 is separated from the upper feed dog 4 and the plate body 5. In between, the cloth is fed forward in the cloth feeding direction by the movement of the upper feed dog 4, and the lower cloth (referred to as the lower cloth) W is fed by the movement of the lower feed dog between the lower feed dog, the presser foot 2, and the separating plate 3. The upper cloth W2 is fed forward in the cloth feeding direction, and since the feed pitch of the upper feed dog 4 is larger than that of the lower feed dog, the upper cloth W2 enters the escape hole 2aK of the presser foot 2 and is bent.

The bent portion is passed through by the needle N and sewn onto the lower cloth W1 by the thread S, thereby forming a pleat G.

Before the pleat G of the fabric W2 in the cloth feeding direction, the presser foot 2 is pushed up by the thickness of the pleat G, creating a gap between the presser foot 2 and the lower surface of the presser foot 2, so that the pressing force of the presser foot 2 acts. Therefore, when the upper feed dog 4 rises, the upper cloth W2
tries to become flat due to its own elasticity, that is, to return to the front in the cloth feeding direction (to the right in Figures 3 and 4), but the inclined surface 5a presses against the lower surface of the presser foot 2 due to its own elastic force. (Fig. 6), the end surface 5b of the plate body 5 is in a state where the cloth W2 is sandwiched between the lower surface of the presser foot 2, and the upper cloth W2 is placed in front of the upper cloth W2 in the cloth feeding direction (to the right in FIG. 3). Since a force is applied to prevent movement of the bent portion G1 and support the bending of the bent portion G1, the bent portion G does not return to its bent position.

Next, when the upper feed dog 4 descends onto the cloth W2, the plate 5 is pressed through the cloth W2, and the inclined surface 5a of the plate 5 is pressed against the separating plate 3 and becomes parallel to the separating plate 3. (FIG. 2), the plate body 5 does not interfere with the feeding operation of the upper feeding dog 4 with respect to the cloth W2.

Note that since the upper and lower fabrics can be separated only by the plate 5, it is possible to omit the separating plate 3 when sewing fabrics that are difficult to skip stitches. For example, a plate body 5 is provided on the throat plate that applies an acting force to the pleats G of the upper cloth W2 during single stitching to prevent it from restoring to the flat state due to the elastic force of the cloth itself toward the front in the cloth feeding direction. Since the presser foot 2 is placed higher than usual by pressing the gather G, the pressing force of the presser foot 2 no longer acts against the bending force of the bent portion G1 (Fig. 3). Also, since the bending portion G1 is always maintained in the bending position by the plate body 5, it is possible to form deep, uniform and beautiful folds.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a conventional pleat stitching device, Fig. 2 is a diagram showing the state in which the bent portion of the upper fabric returns, and Figs. FIG. 5 is a perspective view of the plate, and FIG. 6 is a view showing the action of the plate on the upper fabric.

Claims (1)

[Scope of utility model registration request] The presser foot 2 is supported so as to be movable up and down against the machine frame and presses two pieces of fabric stacked one above the other against the throat plate using elastic force, and the upper and lower fabrics are moved so that the feeding pitch of the upper fabric is larger than that of the lower fabric. In this sewing machine, a relief hole 2a having an edge along the cloth feeding direction is opened downward on the lower surface near the vertical movement path of the needle of the presser foot 2, and The end is placed on the lower surface of the presser foot 2 near the front edge of the escape hole 2a in the cloth feeding direction, and the base is machined so that the free end presses the upper fabric against the lower surface of the presser foot against the elastic force of the presser foot. A pleating device for a sewing machine characterized by having an elastic plate 5 fixed to a frame.