JPH0716369A - Embroidery device for sewing machine - Google Patents

Abstract

PURPOSE:To provide an embroidery device for a sewing machine, by which a thread breakage during sewing of an embroidery pattern can be prevented with a simple method. CONSTITUTION:When an amount of movement of an embroidery frame is a specified value or higher, a stepping motor 20 that performs cutting of a thread is moved from a first position 20a to the position 20c before a second position 20b where a movable knife 23 is released. The stepping motor 20 releases a base station of a thread take-up regulator through a link mechanism 24 to release a tension exerted on the thread. As the phase of release of a thread path is set ahead of that of release position of the movable knife 23, only the thread path can be released with the movable knife 23 out of action, thus a thread breakage during sewing of an embroidery pattern can be prevented with a simple constitution.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sewing machine embroidery device, and more particularly to a sewing machine embroidery device for sewing an embroidery pattern on a cloth held in an embroidery frame by moving the embroidery frame according to embroidery data.

[0002]

2. Description of the Related Art Conventionally, there has been known an automatic embroidery sewing machine in which an embroidery machine is attached to a sewing machine main body and an embroidery frame holding a cloth is set to perform sewing. In such an automatic embroidery sewing machine, the embroidery data stored in advance in the memory (card) is read out, and the embroidery frame is moved in the X and Y directions by the stepping motor to sew various patterns such as complicated sewing lines and embroidery. I am doing it. In that case, since the embroidery data (embroidery pattern) can be arbitrarily changed by exchanging the memory card, it has recently come into widespread use in household sewing machines.

When performing embroidery on the above-mentioned embroidery sewing machine, since the embroidery is performed according to the principle of one-stroke writing, it is necessary to move the pattern over a long distance of several tens of millimeters, which is called a crossover thread.
There is a problem in that the amount of yarn delivered is outside the range of automatic yarn tension, so that the amount of yarn is insufficient and frequent yarn breakage occurs.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and a sewing machine capable of preventing thread breakage when sewing an embroidery pattern by a simple method. An object is to provide an embroidery device.

[0005]

SUMMARY OF THE INVENTION In order to solve this problem, the present invention is held in a hoop by automatic thread tensioning means having a base tension and XY drive means for moving the hoop according to the embroidery data. A sewing machine for sewing an embroidery pattern on a cloth, a thread cutting device for performing thread cutting by driving the stepping motor from a first position to a second position for releasing the moving knife during thread cutting, and a stepping motor Driving means from a first position to a third position between the first and second positions to release the yarn path and release the base tension applied to the yarn. When the above condition is reached, the automatic thread tensioner is stopped and the stepping motor is moved to the third position to apply the base tape to the thread. To release the Deployment, it adopted a structure in which to release the yarn path.

[0006]

Function When the sewing machine is normally sewn, the vertical feed of the cloth of the sewing machine is carried out by the spindle motor and the lateral feed is carried out by the stepping motor for thread trimming. However, when the embroidery machine is attached to the sewing machine main body, the cloth is fed by the hoop. Is carried out by an X and Y direction stepping motor. Therefore, the thread cutting stepping motor is moved to a stop position where the transverse feed function is stopped, and when thread cutting is performed, it is moved from this stop position to a position where the moving knife is released.

The present invention intends to release the yarn path by using such a stepping motor for thread cutting, and at the time of embroidery stitching that requires more than the amount of thread that can be controlled for normal thread delivery, At the predetermined position before the stepping motor is driven to the thread cutting position to release the moving knife, the base tension is released and the automatic thread tensioner is stopped so that the thread can be pulled out without resistance by the movement of the hoop. It is a thing.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the embodiments shown in the drawings.

FIG. 1 schematically shows the construction of the embroidery device of the present invention. In the figure, the control device 10 is
It is composed of a microcomputer, a ROM, a RAM, an I / O port, etc., and controls the entire system. Signals from the input device (key matrix) 14, the frame detection sensor 15, the external memory 16, and the spindle sensor 17 are input to the control device 10.
The input device 14 is an input device that can be operated by an operator and that operates the embroidery sewing machine such as a key for selecting a pattern and a start switch. The frame detection sensor 15 is a sensor that identifies an embroidery frame attached to the embroidery machine and detects its size. The external memory 16 is, for example, in the shape of a memory card and can be attached to the sewing machine main body.
The sewing data of a plurality of patterns are stored therein. The spindle sensor 17 can detect the rotation phase of the spindle that is interlocked with the main motor 18 to detect the height of the needle.

Further, the control device 10 includes a main motor 1
8. The stepping motors 19a and 19b for feeding the embroidery machine 19 in the X and Y directions, the stepping motor 20 for both lateral feed and thread trimming, and the automatic thread tensioning device 21 are connected.
The stepping motors 19a and 19b are connected to the external memory 16
The embroidery pattern 19c is moved in the X and Y directions in accordance with the selected embroidery pattern data stored in the data, and the embroidery pattern is sewn on the cloth held in the embroidery frame.

The amount of thread fed out at the time of sewing is controlled by an automatic thread tension device. In this thread tension device, the thread spool 3
The thread 37 fed from 1 is tensioned by the base tension 32 and guided to the needle 36 via the first solenoid 33, the encoder 38, the auxiliary balance 34, and the second solenoid 35. When the yarn is delivered, the first solenoid is turned off and the second solenoid 35 is turned on. At this time, the auxiliary balance 34 is moved horizontally to move the yarn 37 from the yarn spool 31 by a predetermined amount. This thread feeding amount is
It is calculated according to the sewing parameters such as the needle swing amount, the cloth feed amount, and the cloth thickness. After the calculated yarn feeding amount is accurately detected by the base tension 32 adhering the yarn 37 to the encoder 38, this time, the first solenoid is turned on and the second solenoid is turned off to measure according to the hand movement. Sewing is performed with the thread feeding amount.

The thread trimming stepping motor 20 is also used for laterally feeding the cloth of the sewing machine at the time of normal sewing, and the drive position at that time is indicated by T in FIG. When the embroidery machine is attached to the sewing machine main body, since the cloth is fed by the X and Y direction stepping motors 19a and 19b, the thread trimming stepping motor 20 is moved to the stop position (first position) 20a where the lateral feed function is stopped. Be moved. On the other hand, when thread cutting is performed, the main motor is started, and the thread cutting stepping motor 20 is driven from this stop position to the position 20b, where the rotation of the main motor is used to move the moving knife 23 via the link mechanism 22. Operate and perform thread trimming.

On the other hand, the thread trimming stepping motor 20 is
It can be moved to a position (third position) 20c before the position (second position) 20b where the moving knife is operated, and when the thread trimming stepping motor 20 comes to this position, the base tension is applied via the link mechanism 24. When the tension mechanism of 32 is released and both solenoids 33 and 35 are turned off, the tension applied to the thread is removed, and the thread can be pulled out freely and thread cutting is possible.

In such a structure, the operator of the sewing machine inputs the type of the pattern, the stitch length, the needle swing amount, the strength of the thread tension, etc. through the input device 14. Control device 1
0 stores such information in the internal storage device as parameters. By turning on the start switch of the operator,
The control device 10 detects the start command, drives the main motor 18, and the sewing machine starts moving.

As shown in step S1 of FIG. 3, the embroidery frame is driven by stepping motors 19a and 19b according to the embroidery data read from the memory, and the automatic thread tensioning device is operated to hold the cloth in the embroidery frame 19c. The embroidery pattern is sewn on. In step S2, the next frame movement amount is read out, and in step S3
At, it is determined whether the amount of movement is larger than a predetermined value P. If it is smaller than the predetermined value, the process proceeds to step S4 and the hoop 19c is moved according to the read movement amount.

On the other hand, when it is determined in step S3 that the movement amount is larger than P, the thread trimming stepping motor 20 is moved to the position 20c in step S5. At this time, the base tension 32 is released via the link mechanism 24, and both solenoids 33, 35 of the automatic thread tension device are turned off, whereby the yarn path is released. When the amount of movement (the number of pulses) of the stepping motors 19a and 19b is increased due to the embroidery pattern crossing as described above, and as a result the amount of yarn to be fed out exceeds the control limit amount of the automatic thread tension device 21, the control device 10 The yarn path is released, and the yarn is freely supplied. Even if the frame is moved in step S6, the yarn is pulled out along with the movement of the frame, so that the yarn breakage is prevented.
When the frame movement is completed, the thread trimming stepping motor 20 returns to the position 20a (step S7).

Since the stop clutch is also operated in conjunction with the release of the base tension, the main shaft of the sewing machine is stopped by performing this operation. There is a problem that the hoop will not be able to move if the main shaft keeps rotating because the frame moving time will be long during long distance movement. The problem does not occur even if is long. Also, because it is stopped by the clutch, there is no fear of overrun.

In addition to the embodiment described above, the thread amount is fed out only by turning off the first and second solenoids 33, 35 of the automatic thread tension device without releasing the base tension 32. Even with this, the amount of yarn can be pulled out.

[0019]

As described above, according to the present invention, the stepping motor of the thread cutting device for thread cutting is driven by driving the stepping motor at the time of thread cutting from the first position to the second position for releasing the moving knife. From the first position to the first
Means for releasing the thread path to release the tension applied to the thread by driving the automatic thread tensioning device to a third position between the second position and the second position, and the amount of movement of the hoop exceeds a predetermined value. When this happens, it is possible to release the thread path and prevent thread breakage during sewing of the embroidery pattern.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of an embroidery device of a sewing machine.

FIG. 2 is an explanatory diagram showing operations of thread cutting and thread path release by a thread cutting stepping motor.

FIG. 3 is a flowchart illustrating the operation of the embroidery device.

[Explanation of symbols]

 10 Control Device 14 Input Device 15 Frame Detection Sensor 16 External Memory 17 Spindle Sensor 18 Main Motor 19 Embroidery Machine 20 Thread Cutting Stepping Motor 21 Automatic Thread Tensioner

Claims (2)

[Claims] 1. An embroidery device of a sewing machine for sewing an embroidery pattern on a cloth held in an embroidery frame by an automatic thread tensioning means having a base tension and an XY drive means for moving the embroidery frame according to embroidery data. When the stepping motor is driven from the first position to the second position for releasing the moving knife, the thread trimming device performs thread cutting, and the stepping motor is located between the first position and the first and second positions. By driving to the third position, the base tension is released, and the automatic thread tensioning means is stopped to release the thread path to release the tension applied to the thread. In this case, the sewing machine embroidery device is characterized in that it activates a means for releasing the tension applied to the thread. 2. An embroidery pattern is sewn on a cloth held by an embroidery frame by an automatic thread tensioning means having two thread tension solenoids and a thread feeding section, and XY drive means for moving the embroidery frame according to embroidery data. An embroidery device for a sewing machine, wherein when the amount of movement of the hoop exceeds a predetermined value, the tension applied to the thread is released by turning off the thread tension solenoid.