JPS5912314B2 - How to sew fabric - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION When a tape fabric is spliced to a stretchable body fabric, the amount of feed of the fabric is automatically adjusted depending on the elongation rate of the stretchable body fabric. To provide a new sewing method in which a uniform finished seam without wrinkles, sagging, etc., can be reliably obtained by sewing with tape fabric while adjusting the sewing process.

When sewing tape-like fabrics such as border fabrics to the required peripheral areas of secondary 710 sewn products made of stockinette fabrics and other relatively stretchy wires and woven fabrics,
Depending on the shape of the sewn part, the following sewing problems may occur.

To explain one example of this with respect to drawings, in Figure 1, 1
is the body fabric of underwear etc. made of knitted fabric such as general rubber knitting, and when sewing the tape fabric 2 as the hem fabric on the collar 91 portion 1a of this body fabric 1, for example, the arrow mark on the body fabric 1 As shown in a, the expansion/contraction rate is large in the horizontal direction, and the expansion/contraction rate is small in the vertical direction, as shown by the arrow.

In such a case, attach the tape fabric 2 to the collar part 1a as shown in the figure.
In order P.

In a series of sewn parts up to P, Po-+
P1. P2→P3. Each part between P4 → P6 is body fabric 1
Since it stretches well in the lateral direction, its elongation rate is large;
On the other hand, P1→P2. Since it is difficult to elongate in the vertical direction between P3 and P4, the elongation rate is naturally small.

Therefore, as illustrated in FIGS. 2 and 3, in the sewing section of the known sewing machine, the fabric presser foot 3, the sewing machine needle 4, and the front and rear feed dogs 5 and 6 exposed on the fabric feed plate located directly below the fabric presser foot 3 and the sewing machine needle 4, , the tape fabric 2 is fed through the folding guide 7, etc., and the guide is placed around the body fabric 1, which is also fed onto the fabric feeding plate and fed by the feeding teeth 5 and 6, as shown in FIG. 3A. When the tape fabric 2 which has been folded into two folds according to 7 is overlapped and sewn 8, or when the tape fabric 2 is folded into two folds with one side double folded as shown in the opening of the same figure. 2 are superimposed and sewn 9 (these sewing operations are well known, so the details will be omitted and the summary will be given only). As shown in the first diagram, the elasticity of the body fabric 1 is vertical as a and b. For example, P, which has a large fabric shedding rate, because it differs in the yellow direction.

-+P1. P2→P3tP4→P. If the sewing is performed with the amount of fabric feed depending on the area, such as between the areas, this P.

-+P1. P2→P3. Uniform and beautiful stitching can be obtained between P4 → P6, but the elongation rate of the fabric is small between P1 → P
Since the body fabric 1 is difficult to stretch between P2 and P3→P4, it is sewn under tension, and this P1→P2.
Wrinkles occur on the body fabric 1 side between P3 and P4.

P1 → P2 with a small growth rate of correspondence Q. If the fabric is fed with the fabric feed amount corresponding to P3 → P4, P with a large elongation rate
.

→ P 1 t P 2 → P 3 ° Between P 4 → P 5, the body fabric 1 will be stretched and sewn, so the collar section 1
The stitches used to sew the section a will vary depending on the location, creating technical problems in that uniform stitching cannot be achieved.

In order to solve this problem, the front and rear feed dogs 5.6
A differential feed dog mechanism is known in which the feed amount of the rear feed dog 6 is manually adjusted and changed as necessary.

However, in such sewing work, when processing a large amount of material continuously, it is not practical for the worker to visually check parts of the fabric with different elongation rates and change the feed each time. This is extremely complicated and tiring work,
It is difficult to implement, and variations naturally occur due to individual differences among workers.

The present invention solves these problems, and when a tape fabric with relatively poor elasticity is spliced onto a stretchable body fabric, the fabric is fed by a fabric feed dog mechanism in a sewing machine. The material feed amount is made variable according to the elongation rate in the seamed part, so that the appropriate seam content is always automatically obtained.The feature is that the sewing The point is that the differential amount of the differential feed dog mechanism of the sewing machine is automatically changed according to a preset value corresponding to the number of stitches.

The present invention will be described in detail below with reference to the illustrated embodiments. Fig. 4 shows the spliced and sewn state of body fabric and tape fabric according to the method of the present invention, and Fig. 5 shows the differential feed dog of the sewing machine used in the method of the present invention. The whole perspective view of one example of the mechanism and FIGS. 6 and 7 both show side views of the main parts, but in the present invention, as shown in FIG. 4, the tape fabric 2 is attached to the body fabric 1. When they are attached and sewn together, the illustrated body fabric 1 has elasticity as shown in FIG. They have different properties, and the tape fabric 2 also has the properties of a narrow hem cloth with relatively poor elasticity, as illustrated in FIG.

The body fabric 1 and the tape fabric 2 are sewn together in the sewing section of a known sewing machine as illustrated in FIG. The fabric is fed onto the sewing part by the front and rear feed dogs 5 and 6 exposed on the plate, the sewing machine presser foot 3 is lowered to clamp both fabrics, and the front and rear feed dogs 5 and 6 feed the fabric through the feeding movement shown in FIG. When performing suturing as illustrated in the mouth, the rear feed dog 6 of the front feed dog 5 and the rear feed dog 6 is used.
The feed amount by the front feed dog 5 is made variable with respect to the feed amount by the front feed dog 5, and when sewing the part of the body fabric 1 with the tape fabric 2 whose elongation rate Feed dog 6
The feed rate of the tape fabric 2 is set larger than that of the front feed dog 5, and the sewing machine needle 4 sews the tape fabric 2 with a small elongation rate under a sufficient fabric feed rate. When sewing with the sewing machine needle 4, the feed amount of the rear feed dog 6 is set to be the same as the feed amount of the front feed dog 5, and the sewing is performed with the sewing machine needle 4. The size conversion of the feed amount of the rear feed dog 6 is performed at each conversion position and the required number of stitches between each conversion position, which are preset in the sewing part according to the elongation rate of the body fabric 1. It is converted by counting.

That is, in addition to this count, the control is automatically performed by transmitting or switching appropriate electrical signals.

The sewing machine feed dog mechanism itself using the front and rear feed dogs 5 and 6 is a conventionally known fabric feed mechanism, and both the front feed dog 5 and the rear feed dog 6 in the front and rear feed dog mechanism are synchronously interlocked. do.

In the present invention, as described above, the feed amount of the rear feed dog 6 is made variable with respect to the feed amount of the front feed dog 5, and the variation is automatically performed.

Various mechanisms or means can be considered as necessary mechanisms or means for this purpose, and in the present invention, as one example, 5.
An example shown in Figs. 6 and 7 will be presented.

That is, in FIG. 5.6, among the front and rear feed dogs 5 and 6, a plurality of the front feed teeth 5, three in the illustrated example, are arranged in a row on the plate 10, and the plate 10 is connected to the link 11 arm. 1
2, one end of the link 11 is connected to a swing shaft 13 that can freely rotate back and forth, and one end of the arm 12 is a swing shaft attached to a similar swing shaft 14 that is parallel to the swing shaft 13. The forked portion 12a is engaged with the rod 15, and although one rear feed dog 6 is shown in the figure, it is similarly installed on a plate 16, and the plate 16 is connected to the feed dog 5. arranged in parallel on the same level as the plate 10,
The plate 16 is similarly supported by a link 17 arm 18, and one end of the link 17 is connected to the swing shafts 13, 14.
The arm 18 is connected to a swing shaft 19 provided parallel to the
The forked portion 18a thereof is engaged with a swinging rod 20 attached to the swinging shaft 14 in the same manner as the swinging rod 15.

Further, among the swing shafts 13, 14, 19, the swing shafts 13, 1
4 rotates in one direction and is operatively connected via links 26 and 27 to eccentric crank rods 24 and 25 attached to respective cams 22 and 23 provided on a drive main shaft 21 driven by the driving side of the sewing machine. As a result, the feed teeth 5 and 6 are integrally given back and forth reciprocating motion along an elliptical motion path.

That is, due to the unidirectional rotation of the drive shaft 21, each cam 22.2
3, the rocking shafts 13 and 14 are given rocking motion through reciprocating rotation through the eccentric crank rods 24 and 25 and links 26 and 27, and the plate 10 is rotated through the links 11 and arm 12 through the rocking rod 15. , plate 16 links 17 arms 18
Through the swinging rod 20 and the swinging shaft 19, both plates 10.1
6 is synchronously given a reciprocating motion according to the elliptical motion path d shown in the sixth figure, and as expected from the path d,
When feeding the fabric, it rises and moves forward, and as it rises, the feed dogs 5 and 6 on 10.16 contact and support the fabric with the sewing machine presser foot 2, and move forward to send out a predetermined stroke. At the sending end, the plate 10.16 descends and enters a backward movement, so that it separates from the fabric and the feed dogs 5, 6 become free and repeat the reciprocating movement of retreating together with the plate 10.16, thereby causing the fabric to move backward. This means that a fixed amount of water will be delivered continuously.

Here, in order to independently operate only the rear feed dog 6 and variably adjust its feed amount, which is an object of the present invention, the above-mentioned link 17 is connected as shown in the figure. An operating cylinder 28 such as an air cylinder is connected to the swing shaft 19.
An operating shaft 30 is rotatably moved from the piston rod 28a through 29 links, and an interlocking rod 31 such as a bell crank rod is attached to the operating shaft 30.
One end is pivotally connected by a pin shaft 34 to one end of an eccentric crank rod 33 that is projected from a cam 32 provided on the drive main shaft 21 in the same manner as the cams 22 and 23, and the pin shaft 34 and the aforementioned feed dog 6 side The operating cylinder 2 is connected to the swing shaft 19 of the plate 16 by an interlocking rod 35 such as a bell crank rod.
8, the number of revolutions on the driving shaft side of the sewing machine is detected by a proximity switch, etc., and based on this number of revolutions, the number of vertical and reciprocating strokes of the sewing machine needle 4, that is, the number of stitches, is automatically counted by a counter, etc. When the count number (number of stitches) is reached, an electrical signal is transmitted from a counter or the like, and the cylinder 28 is thereby automatically controlled by an appropriate circuit means. 7 shows the pin shaft of the interlocking rod 31 of the operating shaft 30, and FIG.
This figure shows the motion relationship between the cam 32, the eccentric crank rod 33, and the interlocking rods 31 and 35 between them, and explains the adjustment change in the feed amount of the rear feed dog 6 with respect to the front feed dog 5. Now, when the piston rod 28a of the operating cylinder 28 is lowered, the operating shaft 30 is rotated via the link 29, and thereby the position of the pin shaft 36 of the interlocking rod 31 is changed to the position U in FIG. V (displaced at i position 'U-)V), therefore pin axis 3
If the position 4 is also at the X position when it is at the U position, it changes from the X (i position to the Y position (X-+Y).

Therefore, from the drive main shaft 21, the eccentric crank rod 33 and the pin shaft 3
4, the amount of reciprocating rotation of the interlocking rod 35, and therefore the swing axis 19
The reciprocating rotation angle is larger than that at the U-X position.

This means that the amount of forward movement of the plate 16, that is, the feed dog 6, for feeding out the dough is increased to increase the amount of dough fed, and conversely, the piston rod 28a of the operating cylinder 28 is raised. For example, operate cylinder 2 so that the movement is in the opposite direction and the amount of fabric feed is reduced.
By controlling the 8 side, it is possible to independently adjust and change the fabric feed amount of the rear feed dog 6 with respect to the front feed dog 5, and to do this automatically.

According to one example of the device of the present invention, when sewing the tape fabric 2 to the body fabric 1 as illustrated in FIGS. 1, 2, and 3, the front and rear feed teeth 5 ,6
When feeding by, the feed amount of the front feed dog 5 is fixed,
P shown in the first diagram.

-+P1゜P2→P3. In areas where the fabric elongation rate is high, such as the P and →P6 areas, the piston rod 28a of the operation cylinder 28 is lowered to increase the feed amount of the feed dog 6 than the feed amount of the feed dog 5, and the body fabric 1 It is possible to sew the tape fabric 2 by feeding it out sufficiently, and also to sew the tape fabric 2 from P1 to P.
2. In areas where the dough elongation rate is small, such as from P3 to P4, the piston rod 2.8a of the operation cylinder 2B is raised in the opposite direction to make the feed amount of the feed dog 5 and the feed amount of the feed dog 6 the same (Po -+P1) P2→P3. (less than between P4 → P5) so as to sew tape fabric 2,
In the case where the fabric stretch ratios a and b are different in the longitudinal and lateral directions, the fabric feeding amount can be freely changed, and this change is automated by the automatic control of the cylinder 28 as described above.

That is, for example, P in FIG. When sewing from position P to the left in the figure, that is.

→P when sewing P1.

→The required number of stitches between P1 is nl, and P.

→ Since the dough elongation rate between P1 is large, in this case, first lower the piston rod 28a of the operating cylinder 28 in advance, and then increase the feed amount of the feed dog 6 by more than the feed amount of the feed dog 5. When the body fabric 1 is sufficiently fed out and the tape fabric 2 is sewn, and the number of stitches reaches the above nl, the fabric elongation rate in the next stitched portion between P1 and P2 (number of stitches n2) is small. For this purpose, the piston rod 28a of the cylinder 28 is raised, and the feed amount of the feed dog 5 and the feed amount of the feed dog 6 are made the same and sewing is performed.

That is, P between P1 and P2. -+p is sewn with the feeding amount of the body fabric 1 smaller than the interval, and when the number of stitches between P1→P2 reaches the predetermined number of stitches n2, the next sewing section P2→
P because the fabric elongation rate between P3 (number of stitches n3) is large.

→Same as between P1, increase the feeding amount of body material 1 and P2→P
It is easily possible to sew between 3 and 3 and automatically operate the operating cylinder 28 as the number of stitches is counted as follows: n3→n4→n5.

In other words, the operating cylinder 28 is
The conversion position P of the piston rod 28a.

. Pl, P2. P3. ...and P.

-+ Between P1, between P1→P2, between P2→P3,...
By setting the number of stitches n12 n22 n3)..., the feed amount, that is, the front and rear feed dogs 5,
The difference in feed amount (differential amount) of No. 6 can be automatically changed.

In this embodiment, the difference in the number of front and rear feed dogs 5 and 6 as shown in FIGS. 4 and 5 is because only the body fabric 1 side is changed by the rear feed dog 6 as shown in FIG. This is because the tape fabric 2 is fed only by the front feeding dog 5, and the feeding amount of the body fabric 1 can be adjusted. If the fabric is a woven fabric and is non-stretchable, and the frictional resistance of the fabric is relatively small, the same number of front and rear feed dogs 5 and 6 may be arranged. In addition, when the tape fabric 2 is a stretchable fabric, the fabric 2 may be fed together with the elastic body fabric 1 so as to adjust the feeding amount.

The above is an example of a mechanical conversion means for varying the feed amount of the rear feed dog 6 with respect to the feed amount of the front feed dog 5 in the differential feed dog mechanism of the sewing machine in the method of the present invention. , and is an example of automatic control using the stitch count number to automatically regulate the change timing of the feed rate of the feed dog 6 following it depending on the difference in elongation rate of the target sewn part, and of course, the illustration is an example. Other design changes are of course possible.

That is, by appropriately setting the stroke of the above-mentioned operating cylinder as a means for converting the feed amount of the feed dog 6, the feed amount of the rear feed dog 6 can be made to be equal to the feed amount of the front feed dog 5. It is easily possible to make it the same or smaller.

According to the method of the present invention, when the stretchable body fabric 1 and the tape fabric 2 are spliced and sewn together, if the elongation rate changes depending on the shape of the sewn part of the body fabric 1, etc. The fabric feed rate can be changed to large or small in response to the change in size, and smooth sewing contents that match the local elongation rate can be automatically obtained. There is no possibility of any sagging, and it is easy to achieve a sewing finish with uniform and beautiful continuous stitches over the entire length of the seam.Moreover, this is possible because the operator can manually adjust the feed amount by visual inspection. It is excellent in that it can be done fully automatically, eliminating the difficulty and effort of converting between different parts, and it allows for effective use of unskilled labor, regardless of whether or not they have sewing skills, resulting in uniform and improved sewing quality. It will be possible to make a sufficient contribution to this.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of an example of a sewing structure to which the method of the present invention is applied, Fig. 2 is an explanatory diagram of material feeding and sewing main parts in the same sewing machine, and Fig. 3 is an illustration of an example of a tape fabric sewing structure. 4 is an explanatory diagram of an embodiment of the method of the present invention; FIG. 5 is an overall oblique view of an example of the variable feed dog mechanism used in the method of the present invention;
The figure is a side view of the main part, and FIG. 7 is an interlocking side view of the main part of the operating mechanism. 1...Body fabric, 2...Tape fabric, 3
...Presser foot, 4...Sewing machine needle, 5,6
...Feed dog, 10°16...Plate, 11,17...Link, 12°18...
...Arm, 15,20... Swinging rod, 13゜1
4.19... Swing shaft, 21... Drive main shaft, 22° 23.32... Cam, 24, 25,
33... Eccentric crank rod, 28... Operating cylinder, 30... Open operating shaft, 31, 35...
・Interlocking rod.

Claims (1)

[Claims] 1. A fabric sewing method characterized by automatically changing the differential amount of a differential feed dog mechanism of a sewing machine according to a preset value corresponding to the number of stitches.