JPH0111186Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an empty chain sewing device for an overlock sewing machine.

Conventionally, to prevent the seam from fraying at the beginning of sewing of fabric sewn with an overlock sewing machine, the empty ring that is attached to the end of the sewing start is folded back over the seam on the fabric side, and the seam is secured using a bar tacking sewing machine. It is being done. Although this method reliably prevents the seams from fraying, it requires many steps, such as sewing with an overlock sewing machine, sewing with a bar tack sewing machine, and cutting the loop remaining in the tacking seam. be. In order to simplify this complicated work, the empty ring sewing device prevents fraying at the beginning of sewing by sewing the empty ring connected to the sewing start edge into the seam as soon as sewing starts on the fabric. is provided. As shown in Figures 1A to 1C, this device has a built-in cutting blade b in front of the needle hole a in the feeding direction, and an empty ring holder c that presses and holds the empty ring cut by the cutting blade. When a new cloth is fed to the sewing machine with the empty ring held by the holder c and the sewing machine is driven, the claw d
Even if the hollow ring e formed on the upper part tries to come off the toe due to the extrusion effect caused by the cloth feed, one end is under the pressure of the retainer c, so it does not come off from the pawl and as a result, as the cloth moves. It goes into the back side of the fabric and is sewn into the seams. During this time, the empty ring that is pressed and held by the holder c moves little by little under the holder and finally separates from the holder, but the conventional device only holds the empty ring for a while after sewing starts. Since no consideration is given to the holding section, if the empty ring end moves away from the retainer c when the cloth f reaches the needle hole a (see Figure 1B), the cloth will become stuck as the sewing progresses. As the upper empty ring was pushed out, the empty ring protruded outward from the sewing start end of the fabric as shown in Figure 1c, detracting from the product value.

In addition, the empty ring holder shown in Figures 1A to 1C has a built-in female without exposing it for safety reasons.
When replacing it, the hollow ring holder C had to be removed once, and when it was installed, it was also necessary to adjust the spring to an appropriate strength, making the replacement work extremely troublesome.

This invention aims to eliminate these drawbacks and provide an empty ring sewing device in which the empty ring can be reliably sewn in without protruding from the edge of the fabric, and the knife can be easily replaced.

To explain this using drawings, Fig. 2 shows the overlock sewing machine with the cross plate removed.
It is a base fixed to the side end with a screw, and a female retainer 3 is placed on the base perpendicular to the feeding direction, and is fixed by a set screw 5 fixed through a long hole 4. Fixed. In this state, the upper end surface of the female retainer is formed to be flush with the upper surface of the cross plate.
Although not shown in detail, the knife holder 3 has a split groove formed in the longitudinal direction, and a knife 6 with a blade formed on the left end is inserted into the split groove and tightened with a screw 7. It's summery. Here, the knife is positioned by the ends of the grooves in the longitudinal direction and by touching the base 1 in the vertical direction. A hollow ring holder 8 is also pivotally supported on the base 1 by pins 9.
After a spring 10 is fitted to the end of the pin 9 protruding from the base, a nut 11 is screwed onto the end. Empty ring retainer 8
Under normal conditions, it is in elastic contact with the female retainer 3 and the cross plate so that it can move up and down with its lower surface as the abutting part (see Figures 3 to 5), but its pressing force can be adjusted by turning the nut 11. This is done by moving. The tip of the ring holder 8 is preferably formed in an inclined shape so that the ring can be easily inserted between the ring holder 8 and the cross plate. 14 is a female groove formed inside the hollow ring holder for receiving the knife 6 projecting onto the knife holder 3, 15 is a throat plate, and 16 is a claw. 3 to 5, 17 is a cross plate, 18 is a needle hole, and 19 is a cloth.

Then, the fabric that has been sewn is pulled toward you, and the empty ring that is connected to the end of the sewing is inserted under the empty ring holder 8 and cut with the knife 6, and the empty ring is crossed by the empty ring holder by the action of the spring 10. It is pressed and clamped on the plate and female retainer 3,
Next, feed the fabric 19 under the presser foot (not shown),
When the sewing machine is driven, the empty ring is sewn under the cloth at the start of sewing with one end pressed and held by the holder 8, similar to previous empty ring sewing devices of this type. .

According to this device, when replacing the knife 6 due to deterioration of sharpness, lift the empty ring retainer 8 onto the knife against the action of the spring 10, rotate it counterclockwise in the figure to expose the knife, and then This is done by loosening the screw 7, and by adjusting the rotation of the nut 11 in order to apply the optimum pressing force to the hollow ring according to the thickness and nature of the cloth.

Furthermore, by loosening the setscrew 5 and adjusting the female retainer 3 in the direction of the arrow E in FIG. 2, the holding position of the empty ring by the empty ring retainer can be adjusted.
The hollow ring formed on the claw 16 can be surely sewn into the seam without being removed from the seam.

In the empty ring sewing device constructed as described above, in the present invention, the width of the empty ring holder 8 is set so that the pressing action section m on the empty ring by the empty ring holder 8 is set by the claw 16.
It is formed so that the length n is the same as or slightly longer than the length n.

As a result, when the sewing machine is driven from the state shown in FIG. 3 in which the empty ring cut by the knife 6 is pressed and held by the empty ring holder 8, the sewn cloth 19 is fed and the sewing start end is Until it reaches the tip of the claw, the hollow ring that is pressed by the hollow ring holder moves little by little but is still being pressed by the hollow ring holder, and a new cloth is set under the presser foot, and the fabric is removed. Empty ring e formed on the nail by the time the front end reaches the needle hole a
Although it is pushed out to the tip of the nail, it does not protrude beyond the nail, and is eventually pulled under the fabric and sewn together with the seam.

In the above embodiment, the ring holder is formed wide, but if the ring formed on the claw is held down until it separates from the claw, the width can be made narrower by moving it away from the knife. There is no problem.

As described above, according to this invention, when a new cloth is set under the presser foot and the front end of the cloth reaches the needle hole a, the empty ring e that is formed on the claw is the empty ring that is connected to the seam at the front end of the sewn cloth. Since the ring is completely sewn into the seam under the cloth, the empty ring e will not protrude outside the cloth, and the product value will not be impaired.

In addition, when it becomes necessary to replace the knife due to deterioration in sharpness, etc., lift the empty ring holder against the action of the spring and rotate it to expose the knife. After replacing it, repeat the operation in reverse. All you need to do is
Once the strength of the spring is properly adjusted, there is no need to adjust it each time the spring is replaced, making replacement extremely easy.

[Brief explanation of drawings]

1A to 1C are explanatory diagrams of the operation of the conventional empty chain sewing device, FIG. 2 is a perspective view of the main parts of the sewing machine equipped with the empty chain sewing device according to the present invention, and FIGS. 3 to 5 are the present device. FIG. 1... Base, 2... Sewing machine frame, 3... Knife retainer, 4... Long hole, 5... Set screw, 6...
Female, 7...screw, 8...empty ring retainer, 9...pin, 10...spring, 11...nut, 14...female groove, 15...throat plate, 16...claw.

Claims (1)

[Scope of utility model registration request] This overlock sewing machine is equipped with a knife 6 for cutting the hollow ring attached to the sewing machine frame 2 at a suitable position on the cloth feed side, and a hollow ring holder 8 for elastically pressing and holding the hollow ring on the fabric placement surface. In the empty ring sewing device, the empty ring holder 8 has a presser foot that acts on the held empty ring over an appropriate range from a point away from the knife at least the length of the nail on the throat plate toward the knife. The empty ring sewing device is arranged like this.