JPS5913231B2 - Sewing method and sewing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sewing method and a sewing machine that are conveniently applied when, for example, forming the rear part (heel part) of the upper material of a shoe by sewing.

To form a three-dimensional heel part from the upper material cut into a flat plate, the end surfaces of the left and right rear edges are butted against each other, and a tape is applied from the outside to the rear edge of the shoe, spanning the butted parts. After applying the shaped reinforcing piece, the trailing edge and the reinforcing piece are sewn together to form a single piece.

Conventionally, this sewing work was carried out in the first step of sewing the three parts together so that the thread straddles the abutting part, and at the left rear end of the upper material on both sides of this sewing part. However, with this conventional sewing method, there are various problems such as the following: there were.

In other words, ■ The sewing work is done in two steps, and the sewing length is also long (at least twice the height of the heel - the length from the top of the sole to the top edge of the shoe opening). Work efficiency was extremely poor.

■ Since the sewing methods for the first and second processes are different, it is necessary to install two different sewing machines, which means that
This requires a large space in the sewing workshop, and the semi-finished products must be transported one by one to the second process after the first process is completed, which, in combination with the above item (■), further impairs work efficiency and leads to a significant increase in costs. It was also the cause.

■ The seams formed by the first sewing and the seams formed by the second sewing were not parallel to each other, and the width of the seams became partially wide or narrow, giving the shoes an unsightly appearance.

An object of the present invention is to provide a sewing method and a sewing machine that solve the above-mentioned problems.

The present invention will be explained below with reference to the drawings.

In FIG. 1 showing a sewing machine A according to the present invention, 1 is a base, 2 is a work table placed and fixed on the base 1 and whose horizontal upper surface becomes a sewing work surface 2a, and 3 is a work table placed on the base 1. This is an integrated arm extending above the workbench 2.

A needle bar 4 is held by the arm 3 so as to be movable up and down, and from the lower end surface of a needle support 5 fixed to the lower end of the needle bar 4, four needles, first, second, third, and fourth, which will be described later, are attached. 6, 7, 8, and 9 are suspended toward the sewing work surface 2a.

In addition, three loopers 10 and 1, which will be described later, are provided in the hollow workbench 2 so as to be located near the extension line of the needle bar 4.
1 and 12 are arranged.

The first, second, third, and fourth four needles 6, 7, 8°9 are
As shown in Figure 2, the direction (horizontal direction in the figure) perpendicular to the feeding direction of the material to be sewn (direction from the front side to the back side of the page)
They each have an interval.

In addition, as shown in Fig. 3, the first and second needles 6 of the two middle
, 7 are located in the front row with no front-to-back difference in the feeding direction, while the outer two third and fourth needles 8, 9 have a front-to-back difference in the feeding direction, that is, the loopers 10, 11, The fourth needle 9 closest to the needle 12 is located rearward of the first and second needles 6 and 7, respectively, so that the fourth needle 9 is located rearmost.

Further, in the embodiment, the protrusion length of each needle is the same for the third and fourth needles 8 and 9, and the length of the protrusion of the first needle 6 is approximately 15 mm longer than this.
The second needle 7 is about two periods shorter than the third and fourth needles 8 and 9.

The lengths of the needles 6, 7, 8, and 9 are the same before the needle support 5 is attached, and the depth of insertion into the holes formed in the needles when attached to the needle support 5 is changed. screw 15
, 15..., the length can be adjusted as described above.

Also, the distance between the first needle 6 and the second needle 7 is approximately 4.5 m.
m, the distance between the first needle 6 and the third needle 8, and the distance between the second needle 7 and the fourth needle 9 are each about 3 mm.

The first, second, and third loopers 10, 11, and 12 have the same shape, and as shown in FIG. 2, have front and back differences in the upper end of the looper support arm 13 in the feeding direction. It is screwed in this way.

The lower end of this support arm 13 is screwed to a rod 14 that rotates forward and backward and reciprocates in the feeding direction, so that each looper 10, 11, 12 follows a rectangular trajectory as shown by the arrow in FIG. It will be drawn.

The first looper 10 located in the front row is associated with the first and second needles 6°7, and the second looper 10 located in the middle
1 is associated with the third needle 8, and the third looper located at the rearmost position is associated with the fourth needle 9. Due to the distance between the corresponding looper and the needle, the second Rupa 11, 1st
The support arm 13 is positioned such that the tips of the looper 10 and the third looper 12 are located close to the extension line of the needle bar 4 in this order.
installed on.

With this kind of attachment, the loopers 10, 11, 1 are
The mounting angle with respect to the support arm 13 is adjusted so that the needle plate 2 does not collide with the throat plate 16 that constitutes a part of the sewing work surface 2a.

That is, as shown in FIGS. 2 and 4, the support arm 1
Looper mounting surfaces 13a, 13b, 13c formed in 3
In this case, the mounting surface 13b of the second looper 11 is connected to the support arm 13.
The mounting surface 13a of the first looper 10 and the mounting surface 13c of the third looper 12 are perpendicular to the rotation radius α, and the former is 9o')-4.5 degrees and the latter is 90
It is tilted downward to the right in FIG. 2 so that the angle is -9°.

As shown in FIGS. 5 and 6, each needle 6 is provided on the throat plate 16.
, 7, 8, 9 are inserted through the needle through hole 17°18.19.
The needle through-holes 17 and 18 through which the two first and second needles 6 and 7 are inserted are in communication with each other to form a 38-shaped hole in FIG. There is.

The throat plate 16 also has needle through holes 17.18, 19.20.
A guide plate 21 is provided in a protruding manner at a position further forward in the feeding direction and intermediate between the needle through holes 17 and 18.

In the figure, 22, 22, . . . are openings in which feed teeth (not shown) are arranged, respectively.

7 and 8 show a presser foot 23 attached to a presser bar (not shown) held on the arm 3, and this presser foot 23
A reinforcing piece guide 24 that cooperates with the presser foot 23 to form a rectangular opening is integrated on the back surface of the upwardly curved tip.

As the tip of the presser foot 23 is curved, the rear end surface of the guide plate 21 is also curved to follow this curved shape.

In addition, 38 and 39 in FIG. 3 indicate a needle guard.

Next, the operation of the sewing machine A having the above configuration, that is, the sewing operation will be explained, but this only shows one aspect of the sewing method according to the present invention, and the sewing method of the present invention is not particularly limited to this. It is not something that will be done.

First, the four needle threads 25, 25... (Figs. 13 and 14)
(see figure), the guide roller 26°26... shown in Fig. 1.
27 and a guide rod 28 integrated into the upper end of the needle bar 4.
etc., to the threading holes 6a, 7a of each needle 6, 7, 8.9, respectively.

Insert into 8a and 9a.

In addition, the bobbin threads 29, 29... (see Figs. 13 and 14) are passed through the guide rollers 30, 30, etc. independently, and then arranged together in the workbench 2. A cam mechanism (
(not shown), etc., respectively.
.

Threading holes 10a, 11a opened at the tips of 12.

12a.

When the upper thread 25 and lower thread 29 have been arranged, as shown in FIG. 9, the left rear end edge 31 and The right rear end edge of the second member to be sewn is bent in the direction of the arrow in the figure, the end faces abutted against each other, and the member is placed on the front portion of the throat plate 16 with the front side facing upward.

Further, after passing the elongated tape-shaped reinforcing piece 33, which will become the third member to be sewn, through the reinforcing piece guide 34 attached to the arm 3 and the reinforcing piece guide 24 of the presser foot 23, The rain trailing edge 3 is straddled over the abutting portion of the edges 31 and 32.
1.Pile it on top of 32.

At this time, the guide plate 21 is positioned between the abutting portions of the trailing edges 31 and 32 (see FIGS. 7 and 1).

If you perform sewing in this state, Figures 12, 15,
As shown in FIG. 16, the first and second needles.

6.7 and the first looper 10 cooperate to perform one double chain stitch with two needles, and the third needle 8 and the second looper 11
The fourth needle 9 and the looper 12 cooperate to perform single-needle double chainstitch.

That is, the lower thread 29 inserted through the first looper 10 is as follows.

It straddles between the trailing edges 31 and 32 and intertwines with the upper threads 25 and 25 inserted through the first and second needles 6°7.

In this way, a three-dimensional heel portion 35 is formed at the rear end edge of the instep material B, as shown in FIG.

Note that when the left and right rear edges 31 and 32 are bent as shown by the arrows in FIG. 9, their end surfaces become arc-shaped, so it is difficult to abut all of the end surfaces at the same time, so they are located at the front in the feeding direction. It is best to stitch the pieces by sewing while matching the parts one by one.

That is, as shown by the thin arrows in FIG. 7, it is preferable to perform sewing while applying a slight force such that the end surfaces of the left and right rear edges 31, 32 come into contact with the guide plate 21.

Then, when sewing with this machine, the guide plate 21 allows
The stitches of the thread are made more parallel to the abutting edges of the left and right rear edges 31, 32.

- When the sewing work of the upper material B is completed, the new upper material B to be sewn is subsequently inserted under the reinforcing piece 33, and the above-mentioned work is repeated.

In this way, a plurality of instep materials B are attached to the long reinforcing piece 33.
The reinforcing pieces 33 may be cut at appropriate locations to separate each upper material B.

However, the reinforcing piece 33 may be cut after each sewing operation.

In addition, as shown in FIG. 10, when the reinforcing piece 33 is cut into a long length, after folding the reinforcing piece 33 inward, apply the moon-shaped core 36 from the inside, so that the tip of the reinforcing piece 33 is cut into the upper part. The moon-shaped core 3 is sandwiched between the material B and the moon-shaped core 36.
6, the reinforcing piece 33, and the instep material B are sewn together to form the reinforcing piece 3.
The cut surface of No. 3 is not visible, and a product with good appearance and excellent strength can be obtained.

As shown in FIG. 11, the moon-shaped core 36 may be provided with a tape (eg, bias tape) 37 for covering the peripheral edge to be sewn.

Here, as shown in FIGS. 13 and 14, the first and second needles 6
, 7 and the first looper 10 in cooperation with each other, a single double chain stitch with two needles will be briefly explained.

When the needles 6, 7 penetrate the members to be sewn 31, 32, 33, loops of the needle threads 25, 25 are formed behind the needles 6, 7, and the looper 10 moves through this loop to the left in the figure. Penetrate (1st
Figure 3a).

When the needles 6 and 7 rise and are removed from the members to be sewn 31, 32 and 33, the looper 10 moves slightly forward while passing through the loops of the needle threads 25 and 25 (FIG. 13b).

As the looper 10 moves forward, a loop of the bobbin thread 29 is formed behind it, and the needles 6 and 7 that have descended through this loop are transferred to the previously formed needle 6 and 7 between the two needles 6 and 7. Penetrate it so that the loop is located (Fig. 13d).

The loop 10 regresses so as to pull out the loop of the upper thread 25, and moves slightly backward (Fig. 13e).

Thereafter, the looper 10 advances again to pass through the loop of the upper threads 25, 25 (FIG. 13f), and the same process is repeated thereafter.

That is, in FIG. 14, a''-'e represent the second sewing order.

Note that the double chainstitch using the third needle 8 and the second looper 11 and the fourth needle 9 and the third looper 12 is the same as the conventional method, so a description thereof will be omitted.

In this way, sewing is performed using the four needles 6, 7, 8.9 and the three loopers 10, 11, 12, but the timing of engagement between the needles and the loopers must be set appropriately. Therefore, as mentioned above, the needles 6 and 7°8.9 were made to have different lengths.

Although the embodiments have been described above, the present invention is not limited thereto, and includes, for example, the following cases.

■ The first, second, and third members to be sewn are not limited to the left and right rear edges 31, 32 of the upper material B and the reinforcing piece 33, but may be appropriate materials such as three different sheet materials. Can be done.

Of course, the first, second, and third members to be sewn are in a state in which the end faces of the two members butt each other at the sewn portion, and the remaining member straddles the abutted portion and is overlapped with the two members. The other parts of the first, second, and third members to be sewn may be integrated with each other as desired.

■ Using four needles spaced apart from each other in a direction that intersects the feeding direction of the members to be sewn, the thread is straddled between the first and second members to be sewn, which are abutted against each other by the middle two needles. It is sufficient that the first and third members to be sewn and the second and third members to be sewn are each independently sewn using two outer needles at the same time.

The sewing method according to the present invention has good work efficiency because it performs in one step what conventionally required two steps. Since the stitches are sewn using a needle, the widths between the seams are always parallel, resulting in an excellent appearance on the outside and the top, and there is no need to install two different sewing machines. Therefore, the work space can be reduced and the equipment cost can be reduced.

Further, in the sewing machine according to the present invention, the two middle needles are arranged in the front row without any difference in the front and back in the feeding direction, so that when the sewing work starts, the two needles are placed in the first row with their end faces butted against each other.
, penetrates one and the other of the second member to be sewn without any difference in the front and back,
The double-wave sewing member does not shift back and forth in its feeding direction, and sewing work can be performed accurately and easily.

Moreover, since the four needles are given a front-to-back difference in three steps in the feeding direction, it is possible to make the width of the four needles extremely small, so that the third member to be sewn is the upper material. This is particularly advantageous when it is applied to a narrow piece (approximately 12 ii) such as a heel reinforcement piece.

[Brief explanation of drawings]

FIG. 1 is a simplified front view showing the entire sewing machine according to the present invention;
Fig. 2 is an enlarged front view of the main parts of the sewing machine according to the present invention, Fig. 3 is a top view of Fig. 2, Fig. 4 is a view of the upper end of the looper support arm as seen from the right side of Fig. 2, and Fig. 5 is Top view of throat plate, No. 6
The figures are a sectional view taken along the line Vl-VI in Fig. 5, Fig. 7 is a perspective view of the presser foot portion, Fig. 8 is a sectional view of the presser foot portion along the feeding direction of the material to be sewn, and Fig. 9 is the upper covering material. Fig. 10 is a perspective view showing the heel part of the upper material immediately after the reinforcing piece is sewn on.
Figure 1 is a rear view of the upper material showing the state in which the heel part of the upper material is completed with the moon-shaped core attached, and Figure 12 is the state where the left and right rear edges of the upper material are sewn with the reinforcing piece. Fig. 11 is a sectional view taken along the line ■-■, Fig. 13 a = f and Fig. 14 a '' e are views showing how the thread is intertwined with the two middle needles and one looper, Fig. 15 Figures 16 and 16 show the state of the thread when sewing is performed using the sewing machine of the present invention. Figure 15 shows an enlarged view when seen from the needle side, and Figure 16 shows an enlarged view when seen from the loop side. 5... Needle support, 6, 7, 8, 9...
Needle, 10°11.12... Looper, 25...
...Upper thread, 29...Lower thread, 31...
Left rear edge of instep material (first member to be sewn), 32...
...Right rear edge of instep material (second member to be sewn), 33...
... Reinforcement piece (third member to be sewn).

Claims (1)

[Scope of Claims] 1. The end face of the first member to be sewn and the end face of the second member to be sewn are butted together, and the first and second members to be sewn are made to straddle the abutted portion. a first step of overlapping a third member to be sewn; and a first step of overlapping the third member to be sewn; At the same time, the first, second, and third members to be sewn are sewn together so that the thread straddles the abutting part, and at the same time, two outer needles are used on both sides of the sewn part to sew the first, second, and third members to be sewn. There is also a second sewing method comprising a third sewing member and a second step of independently sewing the second and third members to be sewn. Four needles into which the upper thread is inserted are provided protrudingly at a predetermined interval from each other in a direction intersecting the feeding direction, and the middle two of the four needles are inserted at a predetermined distance from each other in the feeding direction. The two outer needles are positioned at the rear of the two middle needles with a front-to-back difference in the feeding direction, and sewing work is performed between them in the direction of the tips of the four needles. Three loopers, through which the bobbin thread is inserted, are arranged with a front-to-back difference in the feeding direction, with intervening surfaces, and the two middle needles and the one looper located at the frontmost Perform 2 wooden nail chain stitches, and use one of the two outer needles located on the front side, a looper located in the middle, and one needle located on the rear side of the two outer needles.
A sewing machine characterized in that chain stitches are performed using a main needle and a looper located at the rearmost position.