JPS625386A - Empty link stitching apparatus of two-needle overlock sewingmachine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention involves forming an empty ring of a predetermined length after completing the formation of an overlock seam on a fabric, and cutting this empty ring on the fabric side. This invention relates to an empty chain sewing device for a two-needle overlock sewing machine, which holds the side leading to the needle and sews it into a newly formed overlock seam during the next sewing. .

[Prior art]

Overlock stitches using an overlock sewing machine are formed using needle thread, upper louver thread, and lower looper system. After forming the overlock stitch on the fabric, an empty ring is formed to a predetermined length, and then the fabric is sewn. Change direction to the operator side together with the empty ring, stretch the empty ring, cut and clamp the fabric side end with an empty ring holding lid cutter, etc., and place the side of the empty ring that reaches the needle on the needle plate surface. Sewing is performed by holding the empty ring in this state and sewing it into a newly formed overlock seam at the time of the next sewing.

By the way, this type of sewing machine is usually equipped with two louvers as a means of providing thread for forming seams on the fabric, and when performing overlock stitches, the first louver (lower louver) is attached to the bottom of the fabric. The needle moves from the needle to the edge of the fabric in a direction perpendicular to the seam line, and another louver (upper looper) moves from the edge of the fabric to the top of the fabric so as to cross the needle, and by the action of these loopers, the thread An overlock seam is formed beyond the edge of the fabric.

The two-needle overlock sewing machine has two sewing needles as shown in FIG. 1, and each manufacturer has an inner claw and an outer claw on one side of the needle drop. In other words, in Figure 0, where the inner and outer claws are often arranged in parallel on both sides of the needle drop of the outer sewing needle, ■ is the throat plate, 2 is the outer claw, and 3 is the needle drop (M needle) on both sides. )N1. The inner claw with N2, 4, is an empty ring holding and cutting device.

Then, when the sewing work on the fabric is finished, the operator carries the fabric and the empty ring connected to it to the front (turn pack).
When the empty ring is cut and clamped by the empty ring holding/cutting device 4, the empty ring A is held on the needle plate 1 in the state shown in FIG. 2(a).

[Problem that the invention seeks to solve]

However, since the empty ring A is held in the above state, when the needle descends at the beginning of sewing, the needle thread
Since the empty ring A is drawn toward the needle, the outer sewing thread (N2
), and if this happens, there is a problem in that subsequent sewing is not performed and most of the empty loops remain in a protruding state beyond the sewing start portion.

Further, as shown in FIGS. 2(b) and 2(C), the empty ring A that is previously formed and held on the throat plate 1 by the empty ring holding/cutting device 4 is
The outer claw 2 portion is caught by the empty ring A1 that is formed at the start of the next sewing operation.

By the way, the ring A is rod-shaped (a so-called soft chain), and the tightening force of the ring A1 wrapped around the outer periphery of the outer claw 2 is quite large, so the ring A moves to the right in Fig. 2(b). In order to resist this pull, the empty ring holding force of the empty ring holding/cutting device 4 must be increased to a considerable extent, otherwise the empty ring Al will continue to become rod-shaped following the previously formed empty ring A. (Soft chain) is difficult to overlock and does not stably enter the fabric overlock seam. Therefore, if the holding force of the empty ring retainer 4 is increased, the problem arises that the leading edge of the fabric will be pulled and deformed at the beginning of sewing. Occur. or,
As mentioned above, in the overlock stitch, the upper looper forms a loop with the looper thread on the upper surface of the fabric edge, and the sewing thread from the sewing needle engages with this loop to perform sewing. As a result, loop formation by the upper looper is inhibited.

To explain this with reference to FIG. 3, the thread ball square (loop) B formed by the upper looper 5 is pulled by the empty ring A as shown in the figure, and is placed on the side opposite to the sewing needles Nl and N2 across the upper looper 5 (see the figure). In this case, the problem arises that stitch skipping occurs because the stitches are located below the upper looper 5.

[Means for solving problems]

This invention solves the above-mentioned problems by providing an engaging part for locking a hollow ring at the end of the outer claw and forming a hollow ring fitting groove on the upper surface of the outer claw continuously. This is an attempt to find a solution.

〔Example〕

An embodiment of the present invention will be described based on the drawings from FIG. 4 onwards. Note that the same parts as in the conventional example are denoted by the same reference numerals, and redundant explanation will be omitted.

FIG. 4 is an enlarged view of the main part of this embodiment, and in FIG. 6, 2a is a notch serving as an engaging portion of a hollow ring formed at the end of the outer claw 2. As shown in FIG. In this embodiment, the notch 2a is a semicircular recess, but it goes without saying that its shape and structure are not limited as long as it allows the empty ring to enter and exit smoothly. Further, 2b is a hollow ring fitting groove that is formed continuously over the entire length of the upper surface of the outer claw 2 and is continuous with the engaging portion 2a, and the hollow ring A can be almost recessed therein as shown in FIG. 4(b). If so, its cross-sectional shape etc. do not matter.

Next, the operation will be explained with reference to FIGS. 5 and 6.

When the sewing of the fabric is completed, the hollow ring connected to the fabric is locked to the hollow ring engaging portion 2a at the end of the outer claw 2, and the hollow ring A located on the outer claw 2 is inserted into the hollow ring fitting groove 2b. (Fig. 4(b))
(Reference) Bring it to the operator side and cut and clamp the end of the fabric side with the empty ring holding/cutting device 4. Then, when sewing of the next fabric C is started, the empty ring A is held at an appropriate position by the engaging portion 2a without being involved with the outer needle N2.
Empty ring A is sewn smoothly into the overlock seam (
(See Fig. 5) Also, as shown in Fig. 86, the empty ring A
a, and is pulled from this point and clamped to the empty ring holding/cutting device, so no unnecessary force is applied to the loop formation of the upper looper 5, so that the loop can be formed in the proper position, i.e. In FIG. 1, the thread ball square B (loop) is located above the upper looper 5, so the sewing needles Nl and N2 accurately complement this. As shown in FIG. 4(b), the hollow ring A is recessed into the hollow ring fitting groove 2b on the outer claw 2, so that the hollow ring formed before the next sewing is attached to the outer claw. 2
Even if the ring A is formed on the outer periphery of the ring, the tightening of the ring A is not affected by force, so there is no need to increase the holding force of the ring holding and cutting device. No other adverse effects will occur.

〔Effect of the invention〕

As explained above, this invention has a structure in which a retaining portion for locking the empty ring is formed on the outer claw of the throat plate, so that the relative position of the empty ring and the sewing needle is accurately regulated, and the overlapping of the empty ring When sewing into a lock seam, the sewing needle does not sew an empty ring, and the loop of the upper looper is also formed accurately, so it is possible to reliably prevent skipped stitches at the overlock seam. Since no unnecessary force is applied to the previously formed hollow ring in the sewing direction, no special holding force is required for the hollow ring holder, and fabric deformation due to increased holding force can be prevented. This allows for smooth sewing of empty rings.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the main parts of the device in the conventional example, Fig. 2 is an explanatory diagram showing the holding state of the empty ring in the conventional example, and Fig. 3 is a diagram showing the relationship between the loop formation by the upper looper and the empty ring in the conventional example. Figure 4 is an enlarged view of the main part of an embodiment of the present invention,
FIG. 5 is a diagram showing how the hollow ring is sewn in in the embodiment of the present invention, and FIG. 6 is an explanatory diagram showing the relationship between the loop formation by the upper louver and the hollow ring.

Claims (1)

[Claims] An empty ring holding/cutting device is provided on the front side of the needle drop portion, and an engaging portion of the empty ring is formed at the end of the claw provided on the outside of the two sewing needles, and this engagement is provided over almost the entire length of the outer claw. A hollow ring fitting groove continuous to the joining part is provided, and when the fabric is carried to the operator side after sewing the fabric, the hollow ring formed continuous with the fabric is inserted into the engaging part and the hollow ring fitting groove. 2.
Empty chain sewing device for main needle overlock sewing machine.