JPH0363091A - Automatic sewing machine - Google Patents

Abstract

PURPOSE:To enable to avoid a hitch stitch to be formed with the feed direction of an object to be sewn by setting a needle rotational-movement controlling means for moving a needle rotationally so that the guided branch thread of an upper thread piece may be wound on the front side of the needle from the left side of the needle, when the cloth feeding direction of the hitch stitch is judged by a cloth feeding direction discriminating means. CONSTITUTION:To a CPU 14, a floppy disk device 18 for storing the cloth feeding direction in the direction XY stitch by stitch, and a cloth feeding quantity, by every sewing pattern is connected, and an input device 19 for providing the input of sewing data to the floppy disk 18 is connected. When a cloth piece 8 to be sewn is moved in the radial directions (a)-(h) to a needle 7, in other words, when the cloth piece 8 to be sewn is moved in the right direction to the needle 7, and when the guided branch thread 9' of a thread piece 9 is set on the right side of the needle 7, then a hitch stitch is formed. Accordingly, when the guided branch thread 9' of the upper thread piece 9 is contrived to pass the front side of the needle 7 from the left side of it, then the hitch stitch is avoided. Thus, the cloth piece 8 to be sewn is moved in the left direction as shown by the arrow head 2' of a full line, and after that, when the cloth piece 8 is moved to the needle's eye 13 of a marker as shown by a full line 3', the guided branch thread 9'h of an upper thread piece 9h is set on the left side to a needle 7h, and a perfect stitch is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automatic sewing machine that sews a series of seams with perfect stitches using a simple mechanism.

[Prior Art] As shown in FIG. 10, in a conventional automatic sewing machine, a presser foot 3 is fixed to a feed base 4 on a sewing machine table 2 of a sewing machine main body 1, and the base end of the feed base 4 is connected to the sewing machine. Stand 2'
The X and Y direction pulse motors installed on the
It is attached to be movable in the direction and the Y direction, and a frame-shaped cloth presser plate 3 that can hold cloth is fixed to the tip thereof. The presser plate 3 is mounted so as to be slidable in the vertical direction, and the fabric to be sewn is held between the presser plate 3 and a lower plate (not shown). Further, a needle 6 is fixed to a needle bar 5 which is mounted on the sewing machine main body l so as to be movable up and down.

[Problems to be Solved by the Invention] In this type of sewing machine, when the fabric to be sewn held between the presser foot plate 3 and the presser foot lower plate is moved in the XY right direction, the threading of the needle 6 is caused by the movement direction. Either a hit stitch or a perfect stitch is formed depending on where the exit of the upper thread or the lower thread coming out of the bobbin is with respect to the needle 6, and the appearance of the stitch is better with hit stitch than with perfect stitch. There was a problem that the stitching was poor, and the knot points of the seams were likely to come loose.

Therefore, in order to prevent this hit stitch, it has been proposed that the entire sewing machine device is rotated around the needle drop point, and the fabric being sewn in the XY right direction is fed only in the l direction with respect to the needle. (See Japanese Unexamined Patent Publication No. 50-71449).

However, since this sewing machine is large in size and weight, the rotating device that rotates the entire sewing machine is also very large, making the entire sewing machine large and expensive.

In order to solve this problem, a sewing machine has been proposed in which the needle bar and thread catcher are rotated synchronously to remove hitch stitches (see Japanese Patent Publication No. 60-21751). There was a problem in that the configuration for synchronizing the wheel capture device became complicated.

The present invention is intended to eliminate hit stitches formed by the feeding direction of the material to be sewn relative to the needle.

An object of the present invention is to provide an automatic sewing machine that controls the needle thread lead-out thread limb to always be on the perfect stitch side with respect to the needle by moving the fabric to be sewn in a predetermined direction or rotating the needle. It is something to do.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a cloth presser plate and a cloth feed table that can move in the XY right direction while holding the cloth to be sewn,
In an automatic sewing machine that reads a predetermined amount of cloth feed in the XY right direction for each stitch from a control device and controls the movement of the cloth presser plate and the cloth feed base according to the amount of cloth feed, after the start switch is turned on. , cloth feeding direction determining means for determining whether the cloth feeding direction is perfect stitch or hit stitch; and when the cloth feeding direction determining means determines the cloth feeding direction of hit stitch, the lead-out thread limb of the upper thread is on the left side of the needle. After moving the material to be sewn by the material presser plate and material feed table so as to wrap the material toward the front,
A cloth feed control means is provided for controlling the cloth feed amount in the Y-right direction.

In addition, a cloth presser plate and a cloth feed table are provided which can move in the XY right direction while holding the cloth to be sewn, and the control device reads out a predetermined cloth feed amount in the XY right direction for each stitch, and according to the cloth feed amount. , in the automatic sewing machine that controls the movement of the cloth presser plate and the cloth feed table, the cloth feed direction determining means determines whether the cloth feed direction is perfect stitch or hit stitch after turning on a start switch; Needle rotation control means is provided for rotating the needle so that when the direction determination means determines the cloth feeding direction for hit stitch, the lead-out thread limb of the upper thread wraps around the needle from the left side toward the front. be.

[Function] According to the present invention, when sewing is performed with an automatic sewing machine, the feeding direction of the fabric to be sewn in which a perfect stitch is formed by the fabric presser plate and the fabric feeding base is the feeding direction of the fabric to be sewn with respect to the needle. is to the left or its feed direction is backward, and the sewing direction in which hit stitches are formed is that the feed direction of the material to be sewn is rightward or to the front side, so when hit stitches are formed, The sewing machine moves the fabric to be sewn by a predetermined distance to the left with respect to the -meter, and then moves it obliquely to the front by a predetermined distance to the right. Furthermore, when the fabric to be sewn is transferred to the right, it is moved further to the right or diagonally to the right than in the above state. Also, when rotating the needle, be sure to rotate it so that it is on the right side of the upper thread.

[Example] First, before giving a detailed explanation of the present invention, a detailed explanation of the present invention will be given. In FIG. 1, when the fabric 8 to be sewn is moved in the radial directions a' to h' with respect to the needle 7, that is, when the fabric 8 is moved in the direction of area B and area C, the hit stitch is A perfect stitch is formed. However, the sewing material 8 is moved in the radial direction a =
When moving the fabric 8 to the direction h, that is, when moving the fabric 8 in the direction of the A area and the D area, a hit stitch occurs. Here, front, back, left, and right refer to the positional relationship seen from the direction of the tenth arrow. This means that the upper thread 9 enters the needle hole 10 of the needle 7 from the front, as shown in FIG. Since it has come out backwards, when the fabric to be sewn moves in the direction of arrow a=h, the lead-out thread limb 9' of the upper thread 9 will be pulled out from the fabric to be sewn 8, as shown in FIG. It is on the front side of the needle 7 in relation to the thread, and when the needle 7 pierces the fabric 8 to be sewn, the lead-out thread limb 9' of the needle thread 9
is on the rear side of the needle 7, so the stitch 11 is slanted and becomes a hit stitch. That is, when the cloth 8 to be sewn moves to the right with respect to the needle 7, if the lead-out thread limb 9' of the thread 9 is on the right side of the needle 7, a hit stitch is created.

Therefore, as shown in FIG. 4, when the lead-out thread limb 9' of the upper thread 9 is made to pass in front of the needle 7 from the left side.

Hittsuchi stitches are removed.

Therefore, as shown in FIG. 5(a), generally, after the needle bar has risen and the tip of the needle 7 has passed through the upper surface of the fabric 8, the needle 7
The cloth to be sewn 8 is transferred from the stitch 12 to the target stitch by the shortest distance as shown by the dotted line A until the tip of the needle reaches the upper surface of the cloth to be sewn 8.

The needle 7 is transferred to the next stitch 13. However, in the present invention, in the case of the direction of the arrow in FIG.
As shown in a), the fabric to be sewn 8 is moved to the left as shown by the solid line arrow, and then moved to the target stitch 13 as shown by the solid line c. As a result, the lead-out thread limb 9'h of the upper thread 9h in FIG. 4 is on the left side with respect to the needle 7h, resulting in a perfect stitch.

Also, as shown in Fig. 5(b), from stitch top 2 to stitch 1
3. In the case of arrow f in Fig. 2, which moves in the direction of dotted line A,
From the top 2 of the stitches, move the fabric 8 to the left as shown by the solid line arrow, and then move the fabric 8 to the left as shown by the solid line C.
is moved to the front of needle 7, and then moved to the target stitch position 3, as shown by solid line 2.

Furthermore, as shown in FIG. 5(c), in the case of arrow d in FIG. 2, in which the stitch 12 is transferred from stitch 13 in the direction of dotted line A, the workpiece 8 is transferred from stitch 2 to stitch 13 in the direction of the solid arrow. As shown,
Move to the left, move the fabric 8 in front of the needle 7 as shown by solid line C, and then move it to the front of needle 7, as shown by solid line 2.
Move to the target stitch 13.

Also, as shown in Fig. 5(d), from stitch top 2 to stitch 1
3. In the case of arrow 2 in Figure 2, which moves in the direction of dotted line A,
Move the workpiece 8 from the stitch 12 to the left as shown by the solid line arrow, and then move the workpiece 8 as shown by the solid line C.
is moved to the front of the needle 7, and then moved to the target stitch 13 as shown by solid line 2.

In this way, in the present invention, by transporting the fabric 8 to be sewn, the thread limbs 9 of the needle thread 9 are drawn out, as shown in FIG.
' is applied from the left side of needle 7 toward the front, thus making it a perfect stitch.

Referring to FIG. 6, in the control device for the automatic sewing machine according to the embodiment of the present invention, a central processing unit (hereinafter referred to as CPU) 1
4, a read-only memory (hereinafter referred to as ROM) 15 that stores control programs, and a read/write memory (hereinafter referred to as RA) that temporarily stores data from input devices and floppy disks.
M) 16 are connected to form a microcomputer F. Further, a floppy disk device 18 is connected to the CPU 14 for storing the XY force direction and cloth feed amount for each stitch as data for each sewing pattern. In addition, on the input side of the CPU 14, an input device such as a keyboard for inputting sewing data regarding the cloth feed direction and cloth feed amount necessary for forming a sewing pattern onto a floppy disk [19, an input device attached to the main shaft of the sewing machine so that the needle can A pulse generating means 20 for outputting a period from immediately after coming out of the sewing machine to before entering the cloth as a pulse, a starting switch for the sewing machine, and a switch for starting sewing the sewing pattern from the origin position for sewing the sewing machine are provided. Two switch devices etc. are connected. Further, a sewing machine motor 23 is connected to the output side of the CPU 14 via a motor driver 22, and
A pulse motor 25 for feeding in the X direction is connected via a motor driver 24, and a pulse motor 27 for feeding in the Y direction is further connected via a motor driver 26. 27
The feed table 28 is driven by.

The operation of the control device of this embodiment configured as described above will be explained with reference to the flowchart shown in FIG. First, when starting, press the start button of the sewing machine to start the sewing machine (step 1). Next, the pulse motor 25 for feeding in the X and Y directions
．． 27 to send the feed table 28 to the origin position (step 2), and then move the feed table 28 to the sewing start point (step 3). Then, it is determined whether or not the start switch of the switch device 21 is turned on (step 4). If it is turned off, the operation is continued until the ON switch is input.
Keep waiting. Here, if the start switch is turned on, it is determined from the cloth feed direction of the sewing pattern whether it is perfect stitch or pitch stitch shown in Figure 1 (step 5).
The material to be sewn is fed in the direction explained in the figure (step 6), and when sewing of the needle valve is finished (step 7), it is determined whether or not a predetermined number of stitches have been completed (step 8). If n is not completed, return to step 5. Here, if it is a perfect stitch, one normal one-stitch valve is sewn (step 9), and when the number of these stitches reaches a predetermined number n, the sewing is completed.

As described above, in the present invention, a perfect stitch is formed as shown in FIG. 1 by moving the feed table 28 for each needle as shown in FIG. 5 according to the moving direction of the fabric to be sewn. be able to.

In the above embodiment, the feed table 28 was moved as shown in FIG. 5 so that the lead-out thread membrane 9' of the needle thread 9 was placed in front of the needle 7 from the left side. As shown, when the needle 7 is inserted into the upper surface of the fabric to be sewn 8, the lead-out thread membrane 9' of the upper thread 9 should be from the left side of the needle 7 to the front. Alternatively, the hand 7 may be rotated counterclockwise while looking upward until it reaches the top dead center, and then returned to its original position when the hand 7 descends.

Referring to FIG. 8, in a control device for an automatic sewing machine according to another embodiment of the present invention, 14 is a CPU.

15 is a ROM, 16 is a RAM, 17 is a microcomputer, 18 is a floppy disk device, 19 is an input device, 20 is a pulse generating means, 21 is a switch device, 22 is a motor driver, 23 is a sewing machine motor, 24 is a motor driver, 25 is a pulse motor for feeding in the X direction, 26 is a motor driver, 27 is a pulse motor for feeding in the Y direction, and 28 is a feed base, and these structures are the same as the embodiment shown in FIG. 6 above, but in this embodiment. Here, a needle rotation motor 3o is connected via a motor driver 29.

The operation of this embodiment configured in this way will be explained with reference to the flowchart of FIG. First, steps 1 to 5 in FIG. 9 are the same, but in step 6, if the feed of the sewing material 8 is hitch-titch, the needle rotation motor 30 is activated while the needle 7 is rising to the top dead center. After rotating the needle 7 counterclockwise, the needle 7 is returned to its original state before it pierces the sewing material 8. Steps 7 to 9 are the same as the flowchart in FIG. be.

In the embodiment of the present invention, by doing this, the fifth
As shown in the figure, the lead-out thread membrane 9' of the needle thread 9 comes to the front from the left side of the needle 7, thereby making it possible to form a perfect stitch.

[Effects of invention The present invention is configured as described above.

The fabric to be sewn is moved in a specified direction, but only by rotating the needle.
It has the advantage that a perfect stitch is formed and is therefore simple to construct and easy to control.

[Brief explanation of drawings]

The second construction drawing shows the feeding direction of the fabric to be sewn where perfect stitches and hit stitches are formed. Figure 3 shows the relationship between the needle and the stitch where the hit stitch is formed, Figure 4 shows the relationship between the needle and the lead-out thread limb of the needle thread where the perfect stitch is formed, and Figure 5 shows the relationship between the needle and the needle where the perfect stitch is formed. Fig. 6 is a diagram for explaining the direction of movement of the fabric to be sewn so that the needle and needle thread lead-out thread limbs form the perfect stitch as shown in Fig. 4;
7 is a block diagram of an automatic sewing machine control device according to an embodiment of the present invention that moves the cloth to be sewn in the direction shown in FIG. 5.
6 is a flowchart for explaining the operation of the control device shown in FIG. 6, FIG. 8 is a block diagram of a control device for an automatic sewing machine according to another embodiment of the present invention that rotates a needle, and FIG.
10th flowchart explaining the operation of the control device shown in FIG.
The figure is a perspective view of an automatic sewing machine. 14...CPU, 15...ROM, 16...R
A.M. 17... Microcomputer, 18... Floppy disk device, 19... Input device, 20... Pulse generating means, 21... Switch device, 22... Motor driver, 23... Sewing machine motor , 24...Motor driver, 25...X-direction feeding pulse motor, 2
6... Motor driver, 27... Y-direction feeding pulse motor, 28... Feeding base, 29 Motor driver, 3
0...Needle rotation motor.

Claims (1)

[Scope of Claims] 1. A cloth presser plate and a cloth feed table are provided which are movable in the X and Y directions while holding the cloth to be sewn, and a predetermined amount of cloth feed in the X and Y directions for each stitch is read out from a control device, According to the cloth feed amount,
In the automatic sewing machine that controls movement of the cloth presser plate and the cloth feed table, the cloth feed direction determining means determines whether the cloth feed direction is a perfect stitch or a hitch stitch after a start switch is turned on; When the determination means determines the cloth feeding direction of the hitch stitch, the cloth to be sewn is moved by the cloth presser plate and the cloth feed table so that the lead-out thread limb of the upper thread wraps around the needle from the left side toward the front; An automatic sewing machine comprising a cloth feed control means for controlling the cloth feed amount in the X and Y directions for each stitch to the predetermined amount. 2. A cloth presser plate and a cloth feed table are provided which are movable in the X and Y directions while holding the cloth to be sewn, and a predetermined cloth feed amount in the X and Y directions for each stitch is read out from the control device, and according to the cloth feed amount,
In the automatic sewing machine that controls movement of the cloth presser plate and the cloth feed table, the cloth feed direction determining means determines whether the cloth feed direction is a perfect stitch or a hitch stitch after a start switch is turned on; A needle rotation control means is provided for rotating the needle so that when the determination means determines the cloth feeding direction of the hitch stitch, the lead-out thread limb of the upper thread wraps around the needle from the left side to the front. Automatic sewing machine.