JPS6036312B2 - Device to prevent defective stitching at edge tape step of feed-out arm type flat stitch sewing machine for overlapping fabric edges and seaming - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is capable of removing defective stitches at the front edge of the green tape or at the end of sewing by mechanically pulling the empty ring or fabric to an appropriate degree from the rear of a known feeding device. The present invention relates to a method and a device for preventing this.

Conventionally, in feed-out arm type multi-needle flat stitch sewing machines for overlapping fabric edges and seaming, sewing machines for sewing briefs and T
When sewing a shoulder seam on a shirt, if a stepped section of edge tape that overlaps several layers advances, the stepped section should be placed between the presser foot that presses the upper surface of the throat plate through the material, etc. When the green tape tries to sneak in, the front edge of the green tape becomes indented due to resistance, and due to the same reason, the rear green tape protrudes b at the end of sewing, resulting in defective stitching (No. If there is a defect (as shown in Figure 5 A), in order to prevent this, the sewing staff should use their high level of skill to make adjustments one by one to prevent the occurrence of the defective stitching phenomenon as much as possible. However, it was not possible to operate the sewing machine satisfactorily manually, and the occurrence of some defective seams in this area was left unresolved.

In addition, as disclosed in Utility Model Publication No. 43-16136, when two or more pieces of fabric are sewn one on top of the other using an ordinary lockstitch sewing machine, the final ends of the upper and lower fabrics are longer and shorter than each other. The purpose is to prevent irregularities from occurring.
A flat stitch sewing machine is a device related to a sewing machine that is fundamentally different in type, and the fabric feeding device installed in this device encounters the seam orthogonally when performing fan flat stitching on the spliced fabric. There is no function to prevent the stepped portion from becoming stagnant and defective stitching. That is, although this device also has a cloth feed piece and a presser wheel, the presser wheel does not rotate itself but follows the progress of the cloth, and does not have any action of gripping or pulling the cloth. Therefore, there is no effect of preventing stagnation of the stepped portion by traction. However, in the present invention, in addition to the conventionally known feeding device, an auxiliary feeding device is provided to pull the empty ring or the fabric from the rear of the sewing machine, so that the sewing machine does not get stuck between the upper surface of the throat plate and the presser foot. Green tea.

It eliminates the stagnation of the stepped portion, prevents poor sewing phenomena such as indentation of the front green part of the edge tape stepped portion and protrusion of the trailing edge at the end of sewing (as shown in Figure 5 B). It is possible to obtain a straight sewing start c or a straight sewing end d even in the seam section, and it has become possible to perform good sewing even if unskilled people do not have to use any difficulty or carelessness, and the effect is really great. . To explain in detail with reference to the attached drawing showing an example of implementation, 1 is a front feed dog known in the art, 2 is a rear feed dog, 3 is a presser foot, and 4 is a throat plate. This constitutes a known cloth feeding device.

5 is an auxiliary feed dog, 6 is an auxiliary presser foot, 11 is an auxiliary throat plate,
These and other components constitute the auxiliary cloth feeding device of the present invention.

Reference numeral 7 designates a known feed dog mount; the known front feed dog 1 is fixed to the front feed pedestal 7a, and the rear feed dog 2 is fixed to the rear feed pedestal 7, and the cloth is fed by the feeding operation of the feed dog mount. It performs a feeding motion against the back surface.

Reference numeral 8 denotes a feed dog mounting screw, which fixes the base end of the auxiliary feed dog 5 together with the rear feed dog 2 to the feed dog mount 7 in a fixed manner.

Reference numeral 9 denotes the largest hole bored in the wall 1Q' of the arm tip of the sewing machine body, through which the auxiliary feed dog 5 is allowed to swing freely.

Reference numeral 11 denotes an auxiliary throat plate, which is attached to the tip end 12 of the arm of the sewing machine body using two mounting screws 13, 13. When the feed amount of cloth, etc. is to be increased, the auxiliary throat plate 11 is lowered, and when the feed amount is to be decreased, the auxiliary throat plate 11 is raised.

The auxiliary presser foot 6 is swingably attached to the lower end of the auxiliary presser foot mounting shaft 16 using an auxiliary presser foot coupling screw pin 15.
The upper part of the auxiliary presser foot mounting shaft 16 is connected to the auxiliary presser device main body 1.
It is inserted into a vertical hole 18 bored in 7 so as to be movable up and down.
Reference numeral 19 denotes a long hole bored in the main body 17 of the auxiliary presser foot, which passes through the auxiliary presser foot mounting shaft locking screw 20 so as to be movable up and down.

Screw the 20G screw into the auxiliary presser foot mounting mount 16. 21
is a screw hole provided in the upper part of the vertical hole 18 of the auxiliary presser device main body 17, into which the auxiliary presser pressure adjustment screw 22 is screwed.

Reference numeral 23 denotes an auxiliary presser foot spring, which is interposed between the lower end of the auxiliary presser foot pressure adjusting screw 22 and the upper end of the auxiliary presser foot mounting shaft 16, and elastically presses the auxiliary presser foot 6 downward. This allows flexibility in the pressing force of the auxiliary presser foot.

The strength of the elastic force of the auxiliary presser spring 23 is adjusted by turning the auxiliary presser foot pressure adjustment screw 22. 24
is used as a mounting bolt to connect the auxiliary presser device main body 17 to the presser main body 25.

26 is a needle, 27 is a fabric, and 28 is an arrow indicating the direction of fabric movement.

The present invention has the above-described configuration, and generally when the upper surface of the throat plate 4 is placed lower (as shown in the sixth leg), the length of the elliptical trajectory f of the tooth tip g of the feed dog 5 becomes longer, and the fabric This increases the amount of feed.

Therefore, in the present invention, the auxiliary feed dog 5 is newly installed and is fixed to the mounting base 7 of the rear feed dog 2 with the mounting screw 8, so the rear feed dog 2 and the auxiliary feed dog 5 are
The cloth feed amount should be the same. However, in the present invention, since an auxiliary throat plate is newly installed and the auxiliary throat plate is adjusted up and down, the amount of feed of the auxiliary feed dog 5 relative to the rear feed dog 2 can be adjusted by adjusting the auxiliary throat plate 11 up and down. By increasing the feed amount of this auxiliary feed dog 5, the cloth or empty ring, etc. sent by the rear feed dog 2 can be pulled by the auxiliary feed device. It easily achieves the intended purpose, and even when the green tape layer, which is made of several layers and is thick, advances as shown in Figure 7, there will be a slight traction, and it will be difficult to start sewing or sewing. Even in the step part at the end etc., there is a recess a or a protrusion b as shown in Figure 5 A.
This method is highly effective because it can obtain a straight and good sewing start c or sewing end d as shown in Fig. 5 B without causing defective stitches such as the above.

[Brief explanation of the drawing]

The attached drawings show an example of carrying out the present invention, and FIG. 1 is a perspective view of the main parts, FIG. 2 is a side view of the main parts, and FIG. 3 is a front view of the main parts.
Fig. 4 is a plan view of the main part, and Fig. 5 shows the quality of the sewing condition of the step part. FIG. 6 is a side view showing the relationship between the throat plate surface and the feed dog, and FIG. 7 is a sectional view showing the relationship between the stepped portion, the presser foot, and the throat plate. 1... Front feed dog, 2... Rear feed dog, 3... Fabric presser foot,
4... Throat plate, 5.'' Auxiliary feed dog, 6... Auxiliary presser foot, 7
... Rear feed stand, 7a... Front feed stand, 8... Feed dog mounting screw, 9... Upper hole, 10... Wall at the tip of the arm of the sewing machine body. 11... Auxiliary throat plate, 12... Tip of the arm of the sewing machine body, 13...Mounting screw, 15...Connecting screw pin "1
6... Auxiliary presser foot mounting shaft, 17... Auxiliary presser foot device main body, 1
8... Vertical hole, 19... Long hole, 20... Shaft rotation set screw, 21... Threaded hole, 22... Adjustment screw, 23...
Auxiliary presser foot spring, 24... Mounting bolt, 25... Cloth presser body, 26... Needle, 27... Fabric, 28... Fabric traveling direction in Fig. 1 Fig. 2 Fig. 3 Fig. 4 Figure 5 Figure 6 ? figure

Claims (1)

[Claims] 1. An auxiliary feed dog is connected to the rear feed dog of a known feeding device consisting of a front feed dog, a rear feed dog, a presser foot, a throat plate, etc. in a manner that can be interlocked with the rear feed dog, and directly or indirectly assists the presser foot in a swingable manner. A feed-out arm type flat stitch sewing machine for overlapping and seaming the edges of fabric, characterized in that a presser foot is continuously installed and an auxiliary throat plate is installed continuously at the tip of the arm of the sewing machine body so that the vertical position can be adjusted. Defective sewing prevention device.