JPH0686582A - Control method and apparatus for sewing machine - Google Patents

Abstract

PURPOSE:To control feed and sewing motors adequately even when a load fluctuation in a feed mechanism is generated in an electronic cycle sewing machine without using an optimum input pulse table that is set previously. CONSTITUTION:Torques on the shafts of the first and second feed motors 12a and 12b are detected by the first and second detectors 14a and 14b. After a signal processing step, the detected signals are compared with a given reference voltage so that the sewing motor 34 for rotating a sewing belt 36 is controlled in accordance with these results of comparison, while the second feed motors 12a and 12b are controlled for feeding a piece of cloth crosswise or lengthwise to be sewn.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for controlling an electronic cycle sewing machine, etc., which performs lateral movement X-axis drive and vertical movement Y-axis drive in accordance with a sewing pattern to perform arbitrary shape sewing. In particular, it is not necessary to set the optimum input pulse table in advance, and even if the load change occurs in the feed mechanism such as the electronic cycle sewing machine, the drive of the feed motor and the sewing machine motor can be controlled to accurately control the sewing machine. The present invention relates to a sewing machine control method and device.

[0002]

2. Description of the Related Art Known examples of electronic sewing machines include, for example, the invention of the electronic embroidery sewing machine disclosed in JP-A-58-198181. According to the present invention, a sewing machine that moves a needle up and down to form a stitch on a sewn cloth, a holding frame that holds the sewn cloth, a driving means, a first storing means, a pattern selecting means, and an enlarging means, An embroidery pattern is formed on the sewn cloth by providing a computing means, a second storage means, and a central processing unit, and moving the sewn cloth based on prestored embroidery pattern data. And the same person as the applicant filed a patent application.

FIG. 4 is a perspective view of an external structure for explaining an electronic cycle sewing machine which performs lateral movement X-axis drive and vertical movement Y-axis drive in accordance with a sewing pattern to perform arbitrary shape sewing. is there. In this figure, 50 is a workbench, 5
2 is a sewing machine main body, 54 is a needle that has a needle thread on the upper surface and moves up and down, 56 is a rectangular moving frame, 58 is sewn cloth, and 60 is
For example, it is a sewn cloth detector which has a light emitting element and a light receiving element and detects the state of the sewn cloth 58.

In the electronic cycle sewing machine having such a schematic structure, the cloth 58 to be sewn is sewn by the needle 54 while being held by the moving body 56. Further, the sewn cloth detector 60 detects the state of the sewn cloth 58, etc., so that desired sewing can be performed accurately.

On the other hand, the following methods and devices have been conventionally known as methods and devices for controlling the feed rate of sewing machines used in electronic cycle sewing machines and the like. That is, the pulse input to a stepping motor or the like for driving a feed mechanism such as an electronic cycle sewing machine is of a fixed table type, and the sewing machine does not change the predetermined pattern data during sewing. The method and apparatus for controlling the feed rate have been conventionally known.

[0006]

However, in the above-mentioned conventional example, since the input pulse table to be set is the fixed table method, it is necessary to set the optimum input pulse table in the microcomputer in advance, There is a problem that it takes time to repeat the evaluation when setting the pulse.

Further, if the load torque of the drive motor, which is the drive unit, increases due to load fluctuations of the movable part, particularly, weight changes, the rotation of the motor shaft cannot follow and there is a possibility that the feed motor will lose synchronization. There was also the problem of being there.

Further, it is necessary to change the motor and the input pulse table every time the mechanism or the specifications are changed. Therefore, there is also a problem that the evaluation test must be repeated and the pulse test must be performed every time the mechanism or the specifications are changed.

Further, during sewing, since the sewing machine rotation speed is also determined as fixed data with respect to the predetermined pulse table data, there is no variable function of the sewing machine rotation speed for one pulse table. But,
Since the pulse motor affects the speed change of the sewing machine, there is a problem that it is necessary to strictly adjust the rotation speed of the sewing machine before sewing.

In view of the above situation, the present invention has been made to solve the above-mentioned problems of the conventional example, and it is not necessary to set an optimum input pulse table in advance, and an electronic cycle sewing machine or the like can be used. An object of the present invention is to provide a sewing machine control method and device capable of accurately controlling the sewing machine by controlling the driving of the sewing machine motor and the feed motor even when the load changes in the feeding mechanism.

[0011]

According to the present invention, a load torque applied to a shaft of a feed motor for moving a sewn cloth is detected, and the detected signal is signal-processed and then compared with a predetermined reference voltage. According to the comparison result, the drive of the feed motor is controlled to control the feed speed of the cloth to be sewn, and the drive of the sewing machine motor is controlled to solve the above-mentioned problem.

Similarly, according to the present invention, in a sewing machine control device, a first detector for detecting a load torque applied to a shaft of a first feed motor for laterally moving the cloth to be sewn, and the cloth to be sewn. A second detector that detects the load torque applied to the shaft of the second feed motor for longitudinal movement, a detector amplifier that amplifies the output signals of these detectors, and a waveform that receives the output signal of the detector amplifier. A first waveform shaping circuit for shaping, a comparison circuit for comparing an output signal of the first waveform shaping circuit with a reference voltage, a sewing machine motor for rotating the sewing machine belt, and a feed speed of the sewing machine from the rotation of the sewing machine belt. Of the tacho generator, a second waveform shaping circuit which receives the output signal of the tacho generator and shapes the waveform, a signal processing circuit which receives the output signal of the second waveform shaping circuit and processes the signal, A sewing machine speed control circuit that receives the output signal of the processing circuit and outputs a sewing machine speed control signal, and outputs a predetermined information signal by receiving the sewing machine speed control signal, the output signal of the comparison circuit, and the data signal from the data memory Main information processing circuit and the information signal,
An information processing control circuit that receives the sewing machine speed control signal and the output signal of the comparison circuit and outputs a drive signal for the sewing machine motor, and the first and second feed circuits that receive the output signal of the main information processing circuit. And a feed motor control circuit that outputs a drive signal for the motor, and controls the drive of the first and second feed motors according to the output of the comparison circuit to control the feed speed of the sewn fabric. The problem is solved by controlling the drive of the sewing machine motor.

[0013]

The present invention operates as follows.

That is, the load torques applied to the shafts of the first and second feed motors are detected by the first and second detectors, respectively,
After these detection signals are amplified by the detector amplifier, they are sent to the first waveform shaping circuit for waveform shaping. The output signal of the waveform shaping circuit is input to the comparison circuit and compared with the reference voltage signal sent from the reference voltage generator to the comparison circuit. The output signal of this comparison circuit is sent to the main information processing circuit and the information processing control circuit.

On the other hand, the detection signal of the tachogenerator which detects the feed speed of the sewing machine from the rotation of the sewing machine belt is the second signal.
After being sent to the waveform shaping circuit for waveform shaping, predetermined signal processing is performed by the signal processing circuit and sent to the main information processing circuit and the information processing control circuit via the sewing machine speed control circuit.

The main information processing circuit receives the table data signal from the data memory, the output signal of the comparison circuit, and the output signal of the sewing machine speed control circuit, performs predetermined arithmetic processing, and sends the output signal to the motor control circuit. Send out. The output signal of the motor control circuit is amplified by the motor amplifier and then sent to the first and second feed motors.

In this way, according to the signals sent to the first and second feed motors, the first feed motor rotates the shaft of the first feed motor and the second feed motor rotates the shaft of the second feed motor. Let That is, when the detection signals of the first and second detectors are higher than the predetermined reference voltage, the output signal of the main information processing circuit has a wider pulse width than in the normal case,
The rotations of the first and second feed motors are temporarily slowed down via the feed motor control circuit and the like.

The load torque applied to the shaft of the first feed motor is continuously detected by the first detector, and the load torque applied to the shaft of the second feed motor is continuously detected by the second detector. Is sent to the detector amplifier and the above-mentioned signal processing is repeated.

On the other hand, the information processing control circuit receives the output signal of the main information processing control circuit, the output signal of the comparison circuit, and the output signal of the sewing machine speed control circuit, performs predetermined arithmetic processing, and outputs the output signal to the sewing machine motor. Send to.

The sewing machine motor rotates its shaft according to the output signal of the information processing control circuit, and rotates the sewing machine belt via the roller. That is, even in the sewing machine motor,
When the detection signals of the first and second detectors are higher than the predetermined reference voltage, the information processing control circuit temporarily lowers the rotation speed as compared with the normal case.

Further, the rotation of the sewing machine belt, that is, the rotation of the roller is continuously detected by the tachogenerator, the detection signal is sent to the waveform shaping circuit, and the above-mentioned signal processing is repeated.

[0022]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a configuration block circuit diagram for explaining an embodiment of the present invention. In this figure, 10a is a first load such as an X-axis feed mechanism of an electronic cycle sewing machine, 10b is a second load such as a Y-axis feed mechanism of an electronic cycle sewing machine, and 12a is a sewn cloth. First for laterally moving (that is, moving in the X-axis direction)
Of the second feed motor, 12b is a second feed motor for vertically moving the cloth to be sewn (that is, in the Y-axis direction), and 14a is a second feed motor.
The first detector mounted on the shaft of the feed motor 12a and detecting the load torque applied to the shaft, 14b is the feed motor 1
2b is a second detector mounted on the shaft of 2b for detecting a load torque applied to the shaft.

Further, 16 is a detector amplifier for amplifying the output signals of the detectors 14a and 14b, 18a is a first waveform shaping circuit for receiving the output signal of the detector amplifier 16 and performing waveform shaping, and 20 is a comparison circuit. , 22 are reference voltage generators for sending a predetermined reference voltage signal to the comparison circuit 20, and 24 is a second reference voltage generator.
A signal processing circuit that receives the output of the waveform shaping circuit 18b, processes the signal, 26 is a sewing machine speed control circuit, 28 is a main information processing circuit, and 30 is one pulse of data for each sewing pitch, which is stored in advance. Data ROM (Data R) in which various data is read by the main information processing circuit 28.
OM).

Further, 32 is an information processing circuit, 34 is a sewing machine motor, 35 is a roller, 36 is a sewing machine belt, and 38 is
A tacho-generator (T which detects the feed speed of the sewing machine from the rotation of the roller 35, that is, the rotation of the sewing machine belt 36.
G), 40 is a feed motor control circuit, and 42 is a motor amplifier.

As the detectors 14a and 14b, for example, strain gauges for detecting the degree of twist of the shaft are used.

In the embodiment of the present invention composed of such a block circuit, the load torque applied to the shaft of the feed motor 12a is detected by the detector 14a and the feed motor 12b is detected.
When the load torque applied to the shaft is detected by the detector 14b, these detection signals are amplified by the detector amplifier 16 and then sent to the first waveform shaping circuit 18a for waveform shaping.

The output signal of the first waveform shaping circuit 18a is input to the comparison circuit 20 and compared with the reference voltage signal sent from the reference voltage generator 22 to the comparison circuit 20. The output signal of the comparison circuit 20 is sent to the main information processing circuit 28 and the information processing control circuit 32.

On the other hand, the detection signal of the tacho generator 38 is sent to the second waveform shaping circuit 18b to be waveform shaped, and then the signal processing circuit 24 performs a predetermined signal processing. The output signal of the signal processing circuit 24 is signal-processed by the sewing machine speed control circuit 26 and then sent to the main information processing circuit 28 and the information processing control circuit 32.

The main information processing circuit 28 receives the table data signal from the data ROM 30, the output signal of the comparison circuit 30, and the output signal of the sewing machine speed control circuit 26, performs predetermined arithmetic processing, and sends the output signal to the motor. It is sent to the control circuit 40. The output signal of the feed motor control circuit 40 is amplified by the motor amplifier 42 and then fed to the feed motor 12
a, 12b. According to the signals sent to the feed motors 12a and 12b, the feed motor 12a rotates the shaft of the feed motor 12a, and the feed motor 12b rotates the shaft of the feed motor 12b.

The load torque applied to the shaft of the feed motor 12a is continuously detected by the detector 14a, and the load torque applied to the shaft of the feed motor 12b is continuously detected by the detector 14b. The signal is sent to the detector amplifier 16 and the above-mentioned signal processing is repeated.

On the other hand, the information processing control circuit 32 outputs the output signal of the main information processing control circuit 32, the output signal of the comparison circuit 30,
And receiving the output signal of the sewing machine speed control circuit 26, performing predetermined information processing, and outputting the output signal to the sewing machine motor 34.
Send to.

The sewing machine motor 34 is an information processing control circuit 34.
The shaft is rotated in accordance with the output signal of the above, and the belt 36 is rotated via the roller 35. The rotation of the roller 35, that is, the rotation of the sewing machine belt 36 is continuously detected by the tachogenerator 38, the detection signal is sent to the second waveform shaping circuit 18b, and the above-described signal processing is repeated.

FIG. 2 is a flow chart for explaining the operation of this embodiment in detail.

The operation of this embodiment will be described below in more detail with reference to FIG. 1 according to this flowchart.

First, when the feed rate control device of the sewing machine according to the present invention starts operation (step 102 in FIG. 2),
The output signals of the first and second detectors 14a and 14b are processed (step 104 in FIG. 2). That is, the first
The loads applied to the shafts of the second feed motors 12a and 12b are detected by the first and second detectors 14a and 14b, and these detection signals are amplified by the detector amplifier 16 and then sent to the first waveform shaping circuit 18a. It

Next, it is judged whether or not the output signal of the first waveform shaping circuit 18a is lower than the reference voltage (step 106 in FIG. 2). That is, the first waveform shaping circuit 18a
Is output to the comparison circuit 20 and compared with the reference voltage signal sent from the reference voltage generator 22 to the comparison circuit 20.

When it is determined that the output signal of the first waveform shaping circuit 18a is lower than the reference voltage in such comparison, normal operation is performed (step 10 in FIG. 2).
4). That is, signal processing is performed so as to drive the sewing machine motor 34 and the first and second feed motors 12a and 12b at normal rotation speeds.

On the other hand, when it is determined that the output signal of the first waveform shaping circuit 18a is not lower than the reference voltage, the output signal of the comparison circuit 20 is sent to the main information processing circuit 28 (step of FIG. 2). 110) together with the information processing control circuit 3
The output signal of the comparison circuit 20 is also sent to 2 (step 112 in FIG. 2). That is, the output signal of the comparison circuit 20 is sent to the main information processing circuit 28 and the information processing control circuit 32, and signal processing as described later is performed.

First, the comparison circuit 20 is connected to the main information processing circuit 28.
Is output (step 110 in FIG. 2),
The pulse width is extended corresponding to the output signal of the main information processing circuit 28 (step 114 in FIG. 2). That is, the predetermined information signal output from the main information processing circuit 28 is sent to the feed motor control circuit 40, and the pulse width of the pulse signal output from the feed motor control circuit 40 is extended.

The first and second feed motors 12a and 12b are driven according to the output signal of the feed motor control circuit 40 whose pulse width has been extended in this way (step 1 in FIG. 2).
18). That is, the output signal of the feed motor control circuit 40 whose pulse width has been expanded is amplified by the motor amplifier 42 and then sent to the first and second feed motors 12a and 12b.
The first and second feed motors 12a and 12b are driven so as to temporarily reduce the rotation speed of the feed motors 12a and 12b. Since the pulse width is controlled according to the torque in this way, it is not necessary to strictly set the data for each sewing pitch to the optimum value as in the conventional case.

Further, the information processing control circuit 32 includes a comparison circuit 2
An output signal of 0 is input (step 112 in FIG. 2).
Then, the sewing machine speed is reduced by the signal processing in the information processing control circuit 32 (step 116 in FIG. 2).
That is, the information processing control circuit 32 is supplied with the information signal from the main information processing circuit 28, the sewing machine speed control signal from the sewing machine speed control circuit 26, and the output signal of the comparison circuit 20. The information processing control circuit 32 outputs a sewing machine motor drive signal for reducing the speed of the sewing machine according to the output signal of the comparison circuit 20 by the signal processing.

The sewing machine motor 34 is driven according to the sewing machine motor drive signal (step 120 in FIG. 2). That is, a sewing machine motor drive signal, which is an output signal of the information processing control circuit 32, is sent to the sewing machine motor 34, the sewing machine motor 34 is driven in accordance with the drive signal so as to temporarily reduce the rotation speed of the sewing machine, and the roller 35 is driven. The sewing machine belt 36 is rotated via the sewing machine belt 36.

After the driving of the feed motor (step 118 in FIG. 2) and the driving of the sewing machine motor (step 120 in FIG. 2) are performed in this manner, it is determined whether or not the work is completed (FIG. 2). 122). When it is determined that the work is completed, the operation of the feed speed control device for the sewing machine according to the present invention is completed (step 1 in FIG. 2).
24).

However, when it is determined that the work has not been completed, the detection signals of the first and second detectors 14a and 14b are processed again (step 104 in FIG. 2).
The above series of operations is repeated.

The present invention is not limited to the above-mentioned embodiments, but various modifications can be made. The above-described embodiment has been applied to the electronic cycle sewing machine having the X-axis and Y-axis direction feed mechanism, but the application target of the present invention is not limited to this, and for example, the second embodiment shown in FIG. As described above, the present invention can also be applied to a normal sewing machine having only a uniaxial feed mechanism.

[0047]

As described in detail above, according to the present invention, it is not necessary to previously set the optimum input pulse table in the micro-computer or the like as in the conventional example, and it is possible to set a table having an even pulse arrangement. Therefore, there is an advantage that the evaluation time for setting the pulse table, which is required in the conventional example, becomes unnecessary.

Further, even when a load change or a weight change of the movable part occurs, the load torque of the feed motor can be controlled to be constant and the sewing machine speed can be controlled to a desired speed. In particular, even if the load on the motor, which is the drive unit, increases due to a change in weight, it is possible to avoid a phenomenon in which the rotation of the motor shaft cannot follow and is out of step.

Further, it is not necessary to change the feed motor to change the input pulse table every time the mechanism or specifications are changed as in the conventional example, and the evaluation test is repeated every time the mechanism or specifications are changed. There is an advantage that there is no need to perform a pulse test.

Further, since the sewing machine speed is controlled to a desired speed in consideration of the state of the feed motor even during the sewing, there is no influence on the sewing machine speed to the pulse motor, and the number of revolutions is strictly adjusted before sewing. There is also an advantage that there is no need to do it.

Therefore, according to the present invention, a sewing machine control method and device capable of accurately controlling the sewing machine by controlling the drive of the feed motor and the sewing machine motor even when the load changes in the feeding mechanism such as the electronic cycle sewing machine. Will be realized.

If a foreign material such as a finger is mixed into the feed mechanism such as the electronic cycle sewing machine and the load of the feed motor fluctuates, and as a result, a malfunction of the feed mechanism or the like continues for a certain period, the sewing machine is operated. There is also a side effect that it can be stopped automatically.

[Brief description of drawings]

FIG. 1 is a configuration block circuit diagram for explaining an embodiment of the present invention.

FIG. 2 is a flow chart for explaining the operation of the embodiment of the present invention in detail.

FIG. 3 is a configuration block circuit diagram for explaining a second embodiment of the present invention.

FIG. 4 is a schematic configuration perspective view for explaining the external appearance of the electronic sewing machine.

[Explanation of symbols]

 10a, 10b, 10 ... Loads 12a, 12b, 12 ... Feed motors 14a, 14b ... Detector 16 ... Detector amplifiers 18a, 18b ... Waveform shaping circuit 20 ... Comparison circuit 22 ... Reference voltage generator 24 ... Signal processing circuit 26 ... Sewing machine speed control circuit 28 ... Main information processing circuit 30 ... Data ROM 32 ... Information processing control circuit 34 ... Sewing machine motor 35 ... Roller 36 ... Sewing machine belt 38 ... Tacho generator 40 ... Feed motor control circuit 42 ... Motor amplifier

Claims (2)

[Claims] 1. A load torque applied to a shaft of a feed motor for moving a cloth to be sewn is detected, and the detected signal is signal-processed and then compared with a predetermined reference voltage. A method for controlling a sewing machine, characterized in that the drive of a feed motor is controlled to control a feed speed of a cloth to be sewn and a drive of a sewing machine motor is controlled. 2. A first detector for detecting a load torque applied to a shaft of a first feed motor for laterally moving a cloth to be sewn, and a shaft of a second feed motor for vertically moving the cloth to be sewn. A second detector for detecting the load torque; a detector amplifier for amplifying the output signals of these detectors; a first waveform shaping circuit for receiving the output signal of the detector amplifier for waveform shaping; A comparison circuit that receives the output signal of the waveform shaping circuit and compares it with a reference voltage, a sewing machine motor that rotates the sewing machine belt, a tacho generator that detects the sewing machine feed speed from the rotation of the sewing machine belt, and an output of the tacho generator. A second waveform shaping circuit that receives a signal and performs waveform shaping, a signal processing circuit that receives the output signal of the second waveform shaping circuit and performs signal processing, and a sewing machine speed that receives the output signal of the signal processing circuit A sewing machine speed control circuit for outputting a control signal, the sewing machine speed control signal, the output signal of the comparator circuit,
And a main information processing circuit which receives a data signal from the data memory and outputs a predetermined information signal, and a drive signal for the sewing machine motor which receives the information signal, the sewing machine speed control signal and the output signal of the comparison circuit. An information processing control circuit for outputting and a feed motor control circuit for receiving the output signal of the main information processing circuit and outputting a drive signal for the first and second feed motors are provided. In response to the control, the drive of the first and second feed motors is controlled to control the feed speed of the cloth to be sewn, and the drive of the sewing machine motor is also controlled.