JPH01249090A - Contraction sewing machine - Google Patents

Abstract

PURPOSE:To enable execution of contraction having a high grade of a feeling, by a method wherein data required for contraction, previously prepared according to a kind of an object to be sewn and a sewing condition is stored, a compensation amount for a minimum contraction amount of contraction amount changed based on the data is decided, and a walking amount is set. CONSTITUTION:In consideration of a quality of the cloth of an object to be sewn, a sewing speed, and the length of a notch section from data previously obtained by trial sewing, a compensation value factor K of a walking amount is set. When a walking amount enters a notch section B, a compensation amount alpha added to a first one stitch is computed by multiplying an absolute difference between an ordinary walking amount P0 and a maximum walking amount P1 by the compensation value factor K. A contraction amount beta at each one stitch is determined by dividing a difference between an absolute value and the compensation amount alpha by the number S1 of needles. With this state, a walking amount of one stitch is set to alpha+beta, and a first one stitch is sewn. Since a walking amount of the first one stitch is a compensated walking amount, contraction is actually applied on a cloth, and a walking amount on and following a second stitch is increased by beta at each one stitch. This constitution prevents production of a part where no contraction is made.

Description

[Detailed description of the invention] (Industrial field of application) The present invention relates to a shirring sewing machine used for attaching sleeves, etc.
In particular, the present invention relates to a shirring sewing machine that automatically controls the upper feed amount at the start or end of shirring to an optimum amount.

[Conventional technology]

Conventionally, in this type of shirring sewing machine, when sewing a sleeve l to a body part 2, as shown in FIG. '.

Sleeve l so that b', c', d', and e' match.
must be prepared.

For this reason, in conventional shirring sewing machines, the upper feed amount, the upper shirring feed amount, and the number of sewing stitches in between are usually set, and the upper feed is adjusted by a stepping motor so that the upper shirring feed amount changes evenly. It controls the axis. That is, in the conventional shirring sewing machine, the upper feed adjustment axis is mechanically controlled based on an ideal shirring curve as shown by the dashed line in FIG.

In Fig. 5, the notch section A indicates a normal upper feed section where the upper feed amount and the lower feed amount are 1:10 (for example, the upper feed amount is 2 mm), and the notch section C indicates the section having the maximum shirring amount. , the upper feed amount of notch sections B and D during this period is 1
The upper feed amount is controlled so that it changes evenly for each needle.

However, in order to facilitate understanding, FIG. 5 depicts the relationship between the mechanical upward feed amount and the actual shirring amount in a somewhat exaggerated manner.

[Problems to be Solved by the Invention] However, the actual shirring amount of the fabric varies depending on the fabric quality, sewing speed, etc. as shown by the solid line in FIG. , shirring Ik) is small, a sufficient upward feed amount cannot be obtained due to friction between the upper and lower fabrics, so that only shirring appears on the fabric, resulting in uneven shirring and poor sewing quality.

The present invention improves this point, and aims to provide a shirring sewing machine that can perform shirring with a high texture without causing any portions of the fabric where shirring does not appear.

[Means for solving problems]

In the present invention, the upper feed amount is controlled so that the first stitch (the last stitch in the case of return) is given a larger shirring amount than other parts.

[Effect]

Therefore, the amount of shirring that is actually sewn onto the fabric can follow the amount of shirring mechanically applied from the first stitch (to the last stitch in the case of return), and it is possible to eliminate areas where shirring is not applied. It is also possible to create a texture even when sewing parts where the amount of shirring does not change much.

〔Example〕

An embodiment of the present invention will be described based on the drawings.

FIG. 1 shows a circuit diagram of a main part of an embodiment of the present invention. 1st
In the figure, 1 indicates the sewing data setting RAM, and this #A! li
! A setting switch 2 is connected to the data setting RAM 1 as a constant. Further, 3 indicates a shirring switch, and the output of this shirring switch 3 is the shirring flag setting circuit 5.
It is connected to a comparison circuit 6 which compares the contents of the data. The output of this comparison circuit 6 is connected to a comparison circuit 7 that performs a comparison with the upper feed position signal C, and the output of this comparison circuit 7 is exclusive O
The other input terminal of the exclusive OR circuit 8 is connected to the output of the shirring flag setting circuit 5. The output of this exclusive OR circuit 8 is the arithmetic circuit 9
The output of this arithmetic circuit 9 is connected to the arithmetic practical RAM
Connected to l0. Further, the output of the arithmetic circuit 9 is connected to a stitch number counter 11, and the output of this counting counter 11 is connected to a comparison circuit 12. This comparison circuit 1
2 is bidirectionally connected to the arithmetic operation practical RAM 10.

In FIG. 1, 19 is a reset circuit, 20 is a thread trimming signal detection circuit, 21 is a display circuit, 22 is a panel switch,
23 is a rotation signal detection circuit, 25 is an upper position signal detection circuit,
26 and 27 are pulse counters, 28 is an origin detection sensor, 29 is an upper feeder, 30 is a pulse motor, and 31 is a pulse motor driver, respectively. Furthermore, 4 in Figure 1
0.41.42.43.44 each indicate an AND gate, 50 and 51 indicate an OR gate, and 52 and 53 indicate an inversion gate. These components are connected as shown in FIG.

FIG. 2 is a flowchart of one embodiment of the present invention.

FIG. 3 shows an explanatory diagram of the operation of one embodiment of the present invention.

However, in order to facilitate understanding, FIG. 3 depicts the relationship between the mechanical upward feed amount and the actual shirring amount in a somewhat exaggerated manner. Also, in FIG. 3, the same parts as in FIG. 5 indicate the same parts as in FIG. 5, respectively.

(Operation) The characteristic operation of the embodiment of the present invention configured as described above will be explained.Referring to FIG. 2, power is applied and initialization is performed by the reset circuit 19 (block 61 in FIG. 2).
162, hereinafter simply referred to as "block". ). In this state, the operator selects a compensation value for the upper feed amount by using the constant setting switch/key 2, taking into consideration the fabric quality of the workpiece, sewing speed, notch section length, etc., from the data obtained from trial sewing in advance. Set the coefficient K in the sewing data setting RAMI.

Here, the compensation value coefficient for the above-mentioned upper feed amount is one of the features of the present invention, and as mentioned above, the material to be sewn is actually sewn by varying the fabric quality, sewing speed, notch section length, etc. Test-sewing a sample of the product and actually shirring the first stitch and last stitch (i.e., the minimum shirring amount) into the fabric, which are determined according to the various sewing conditions of the product to be sewn. This is a compensation value coefficient for the upper feed amount to compensate for the upper feed amount necessary to perform the above. In this embodiment, the compensation value coefficient for the upper feed amount is 1.
Limited to less than 00%.

In addition, the operator (see Fig. 3) selects the initial upper feed amount Po (that is, the upper feed amount when there is no shirring and the lower feed amount and the upper feed amount are equal) and the maximum shirring amount using the panel switch 22. The upper feed ip, the number of stitches in the notch section B where the shirring amount increases sequentially, 51, the number of stitches in the notch section B where the shirring amount sequentially decreases, etc. are set in the sewing data setting RAMI (block 65). .

In this state, when the notch section B is reached, the operator turns on the shirring switch 3 (block 66).

As a result, the AND game 1-41 is closed and data updating to the sewing data setting RAMI is prohibited.

Further, at this time, the shirring flag setting circuit 5 is OFF, the upper feed amount is P, the number of stitches S in the notch section B is set in the stitch number counter ll, and the shirring 7 lag setting circuit 5 is It is turned ON by the output of the exclusive OR circuit 8 (blocks 66 to 70).

In this state, in block 73, the number of stitches in this section is N (i.e.,
It is determined whether S+) is 2 or more.

Further, if the number of stitches N is 2 or more, the above-mentioned compensation amount α added to the first stitch is determined by the calculation circuit 9 as shown in block 74, the normal upper feed amount P, (the upper It is calculated by multiplying the absolute difference between the maximum upper feed amount P1 (upper feed fi at the maximum shirring amount) by the compensation value coefficient K of the upper feed amount.

In addition, the shirring amount β for each stitch is determined by the arithmetic circuit 9.
5, it is obtained by dividing the difference between the absolute difference (i.e., IPI-P, I) and the compensation itI by the number of stitches, 81.

The result of this calculation is set in the practical RAM l0 (
block 76).

In this state, the rotation signal detection circuit 23 detects that the sewing machine is rotating, the upper position signal detection circuit 25 detects the upper position, and the stitch number counter 11 determines that the number of stitches N is 2 or more. When the shirring flag ON is detected from the shirring flag setting circuit 5 and the first stitch is detected from the comparison circuit 12, the upward feed amount of the first stitch is determined by the pulse counter 2.
6, the set content PC-α+β is set as shown in block 82, and the content of the stitch number counter 11 is incremented by 1 (blocks 77 to 83).

The contents PC-α+β of the pulse counter 26 are sent to the pulse motor driver 31 through the AND gates 42 and 44 and the OR gate 51, the pulse motor 30 is driven, and the upper feed amount is set. be sewn. At this time, the top feed amount P of the stitch currently being sewn is the maximum top feed amount P.

Or, it is determined whether the upper feed amount is the normal upper feed amount P0 without shirring (blocks 87 and 88).

Here, since the upper feed amount of the first stitch is the upper feed amount compensated by the above α, the cloth is actually shirred,
Unlike conventional sewing machines, there are no parts that are not shirred. This is a feature of the present invention.

Since this is the first stitch of notch section B, the determination results in blocks 87 and 88 are NO, and while the set number of stitches S
A loop between 7 and 88 is repeated. In this case, the determination after the 2nd stitch is NO in block 81, and the upper feed amount after the 2nd stitch is set in the pulse counter 27 as set contents PC=β as shown in block 89, and the upper feed amount is changed to β for each stitch.
will only be increased.

When the set number of stitches S1 is shirred, the printer 88 determines that the current upper feed amount P is the maximum upper feed amount 1) 1, and the notched section C is sewn by the loop of blocks 66 to 68. . That is, in this notch interval C, the upper feed amount is a constant value P, and during the notch interval C, the upper feed amount is maintained at the upper feed amount P by the pulse motor 30, and shirring stitches are performed.

When the shirring of the notch section C is completed, the operator turns off the shirring switch 3 (block 66). At this time, the shirring flag setting circuit 5 is ON, the upper feed amount is P, the number of stitches in the notch interval 52 is set in the stitch number counter 11, and the shirring flag setting circuit 5 is set to exclusive OR. It is turned off by the output of circuit 8 (block 9
3-96).

In this state, in block 73, the number of stitches in this section is N (i.e.,
It is determined whether St) is 2 or more.

Further, if the number of stitches N is 2 or more, the compensation amount α' to be added to the last first stitch is calculated by the calculation circuit 9 as shown in block 74. However, in this embodiment, since P and ' are the same as Pl, α and α' are the same. In addition, the shirring amount β° for each stitch in the notch section is determined by the block 75 in the arithmetic circuit 9.
It is obtained by dividing the difference between the absolute difference (i.e., lp' + -pal) and the compensation amount α' by the number of stitches, 52, as shown in FIG.

This calculation result is set in the calculation result practical RAM l0 (
block 76).

In this state, the rotation signal detection circuit 23 detects that the sewing machine is rotating, the upper position signal detection circuit 25 detects the upper position, and the stitch number counter 11 determines that the number of stitches S is 2 or more, The shirring flag setting circuit 5 detects that the shirring flag is OFF (blocks 77 to 80).

Further, in block 90, when the comparison circuit 12 detects that it is the first stitch in the notch interval, the upward feed amount of the lth stitch is set in the pulse counter 27 as the set content PC-β' as shown in block 91. Further, the contents of the stitch number counter 11 are incremented by 1 (blocks 90, 91, 83). The content pc-β1 of this pulse counter 27 is AND gate 4
2 and 44, are sent to the pulse motor driver 31 through the OR gate 51, the pulse motor 30 is driven, and the upper feed amount β' is set, and the lth stitch in the notch section is Pl-β'
It is shirred by the upper feed amount. At this time, it is determined whether the top feed amount P of the seam currently being sewn is the maximum top feed amount P1 or the normal top feed ip in which shirring is not performed (blocks 87 and 88).

Since this is the first stitch in the notch section, the determination results in blocks 87 and 88 are NO, and from the second stitch onwards, the loop between blocks 77-80, 90, 91, 83-88 is repeated, and each The upper feed amount is reduced by β″ for each stitch.

The last stitch and block 9 where the count in &ia is in the notch section
If it is determined to be 0, the upper feed amount of the last stitch is displayed in the pulse counter>6 as shown in block 92, and the set contents PC-σ
° +β'' (block 90.92). The contents of the pulse counter 26, PC=α°+β', are passed through the AND gates 42 and 44 and the OR gate 51 to the pulse motor driver 31 in the same manner as described above. The Rehals motor 3O is driven, and the upper feed amount σ゛1β' is set.
The final stitch in the notched section is shirred with an upward feed amount of α″10β″.

Here, since the upper feed amount of the final stitch is the upper feed amount compensated for by α', the cloth is actually shirred, although the shirring amount is small. This is a feature of the present invention.

Further, when the number of sewing stitches N is determined to be 1 in block 73,
The amount of shirring is calculated as shown in block 98, and this value is set in the pulse counter 27 (block 99), and the following operations are similar to those described above.

〔effect〕

As explained above, in the present invention, the upward feed amount is controlled so that the first stitch (the last stitch in the case of return) is given a larger shirring amount than other parts.

Therefore, the amount of shirring that is actually sewn onto the fabric can follow the amount of shirring mechanically applied from the first stitch (or the last stitch in the case of return), and it is possible to eliminate areas where shirring is not applied. It has the effect of giving a texture even when sewing parts where the amount of shirring changes little.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the main circuit configuration of an embodiment of the present invention. FIG. 2 is a 70-chart of one embodiment of the present invention. FIG. 3 is an explanatory diagram of the operation of one embodiment of the present invention. FIGS. 4(a) and 4(b) are explanatory diagrams of the shirring mat. FIG. 5 is an explanatory diagram of the operation of the conventional device. 1 Sewing data setting RAM 2 Constant setting switch 3 Preparation switch 5 Preparation flag setting circuit 6.7.12
Comparison circuit a Exclusive OR circuit 9 Arithmetic circuit 10 71@RAM3G for calculation i
Pulse motor 31 Pulse motor driver Fig. 3 Fig. 4

Claims (3)

[Claims] (1) In a shirring machine that shirps a part where the shirring amount changes sequentially by uniformly changing the top feed amount, the shirring sewing machine shirps the part where the shirring amount changes sequentially by uniformly changing the top feed amount. a first means for storing data for obtaining the minimum upper feed amount necessary for actually applying shirring; and selecting the data from the stored contents of the first means according to the material to be sewn and the sewing conditions. a second means; a third means for determining a compensation value for the minimum shirring amount of the sequentially changing shirring amount based on the data selected by the second means; and fourth means for setting the upper feed amount corresponding to the minimum shirring amount based on the compensation value determined. (2) The shirring sewing machine according to claim 1, wherein the minimum shirring amount compensated by the compensation value is the shirring amount of the first stitch when the shirring amount increases sequentially. (3) The shirring sewing machine according to claim 1 or 2, wherein the minimum shirring amount compensated by the compensation value is the shirring amount of the last first stitch when the shirring amount decreases sequentially.