JPH0228355B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a sewing machine, and particularly to a sewing machine that uses a common control device but has different control contents depending on whether a thread removal device is used or not. Regarding.

[Prior Art] In general, industrial sewing machines start the thread cutting operation by depressing the pedal backwards, and then operate the thread-wiping wiper after detecting that the needle has reached the upper position. Excite the electromagnetic solenoid to drive the. The wiper is then returned to its original position by the action of a spring. For this reason, even if the pedal is pressed forward immediately after the pedal is pressed again, the sewing operation is started after a predetermined delay time that allows enough time for the wiper to return to its original position due to the action of the spring.

However, if thread wiping operation is not required, even if the circuit of the electromagnetic solenoid is opened or the thread wiping device is removed, the control device remains the same.
The sewing operation cannot be started until after waiting for the operating time of the thread removing device. In other words, the time required to start sewing again after the thread cutting operation was the same whether the thread removing device was used or not.

[Problems to be Solved by the Invention] In order to improve work efficiency, it is desirable to start sewing work as soon as possible by reducing the idle time when the pedal is pressed forward.
In the above-mentioned conventional device, when the thread removing device is not used, a time period corresponding to the operating time of the thread removing device is generated. This invention eliminates this drawback and increases work efficiency.

[Means for Solving the Problems] The present invention provides a detection device for detecting whether or not a thread removing device is connected to an output circuit of a control device, and when the thread removing device is connected, the sewing operation is stopped. Even if the operating member is operated to restart the operation, the output of the signal for re-driving will be delayed until the thread removing device returns to its normal position, and if the thread removing device is not connected to the output circuit, the operating member will In response to the above operation, the sewing operation is controlled to restart the sewing operation.

[Function] As a result, when using the thread removing device,
To enable safe operation by preventing sewing work from being started until a thread removing device returns to its normal position. Furthermore, when the thread removing device is not used, the time required for the operation of the thread removing device is eliminated, and sewing work can be started promptly, thereby improving work efficiency.

[Embodiment] In the figure, reference numeral 1 denotes a sewing machine head, which has a needle 4 that is moved up and down with respect to a support surface 3 for a workpiece to be sewn by a drive device 2 consisting of a motor with a brake. Reference numeral 5 denotes a thread cutting device which detachably connects a cutter 5a provided under the workpiece support surface 3, a cam 5b that rotates in synchronization with the vertical movement of the needle 4, and the cutter 5a and cam 5b. It consists of an electromagnetic solenoid 5c.

Reference numeral 6 denotes a thread removing device, which includes a wiper 6a that is swingably provided so that its lower end bent portion moves across the vertical movement trajectory of the needle 4, an electromagnetic solenoid 6b that drives this wiper, and a wiper that moves the wiper normally. and a spring (not shown) for returning it to the position.

Reference numeral 7 denotes a pedal as an operating member, which is supported substantially in the center so as to be able to swing around a horizontal axis, and its swing operation operates the forward depression signal output device 8 and the pedal depression signal output device 9.

10 is a needle position detection device. Reference numeral 11 denotes a control device consisting of a central processing unit (CPU) and a storage means, and includes a forward pedal depression signal output device 8, a pedal depression signal output device 9, a needle position detection device 10, and a thread removal device detection device 12 to be described later. In response to the signal, the electromagnetic solenoids 5c and 6b of the drive device 2, the yarn cutting device, and the yarn removing device are controlled.

Reference numeral 12 denotes a detection device for detecting whether or not the thread removing device is connected to the output circuit of the control device 11.

FIG. 2 shows a specific example of the drive circuit and detection device 12 for the electromagnetic solenoid 6b of the thread removing device. is connected to the collector terminal of the A transistor TR2 in the detection device 12 connects its base terminal to the transistor through a resistor R1.
The collector terminal of the transistor TR2 is connected to the input terminal of the control device 11. R2, R3, R4 are resistances, D
is a diode. SW is electromagnetic solenoid 6b
This is a switch that connects and disconnects the drive circuit to and from the drive circuit.

When the pedal 7 is depressed forward, the control device 11 outputs a sewing machine operation signal to the drive device 2 in response to a signal from the forward depression signal output device 8, and starts sewing work. When the pedal 7 is returned to the neutral position, the control device 11 outputs a sewing machine stop signal based on the signal from the output device 8, and the sewing machine stops with the needle 4 in the lower position based on the signal from the needle position detection device 10. . When the pedal 7 is pressed backward, the control device 11 responds to the signal from the pedal 7 signal output device 9.
outputs a sewing machine operation signal, moves the needle 4 upward from the lower position, simultaneously outputs a thread cutting signal, energizes the electromagnetic solenoid 5c of the thread cutting device, and activates the cam 5.
A cutter 5a is connected to b, and the cutter 5a is operated in synchronization with the upward movement of the needle 4. This allows the thread that contributes to sewing to be cut under the object to be sewn.

Thereafter, in response to a signal from the needle position detection device 10 based on the fact that the needle 4 has reached the upper position, the control device 11 outputs a sewing machine stop signal to the drive device 2 and at the same time outputs a brake signal, so that the needle 4 reaches the upper position. Stop it in a state. Further, the excitation of the electromagnetic solenoid 5c of the yarn cutting device is also released to stop the operation of the cutter 5a.

When the switch SW of the drive circuit for the electromagnetic solenoid 6b in the thread removing device is closed, power V is applied to the collector of the transistor TR1 through the electromagnetic solenoid 6b, and similarly, the transistor TR2 is turned on via the resistors R1 and R2. . As a result, a signal indicating that the electromagnetic solenoid 6b is connected to the output circuit of the control device 11 is inputted to the control device 11. As a result, the control device 11 outputs the thread removal signal 20 milliseconds after outputting the sewing machine stop signal based on the contents of the storage means, and outputs the thread removal signal, and the transistor TR
1 is turned on to excite the electromagnetic solenoid 6b. Thereby, the wiper 6a can be swung in one direction across the bottom of the needle 4, and the end of the thread on the needle side after cutting can be pulled out from the workpiece and moved upward.

Thereafter, the control device 11 performs the following every 20 milliseconds:
Brake operation stop signal and electromagnetic solenoid 6b
Outputs an excitation stop signal. However, even if you immediately step forward on the pedal 7 and operate the forward pedal signal output device 8 at this point, the time required for the wiper 6a to return to its normal position due to the action of the spring is e.g.
The control device 11 does not output the sewing machine operation signal until 40 milliseconds have elapsed.

If the switch SW in the drive circuit of the electromagnetic solenoid 6b in the thread removing device is opened, or if the entire thread removing device is removed together with the electromagnetic solenoid 6b, the transistor TR2 of the detection device 12
turns off and inputs a signal to the control device 11 indicating that the electromagnetic solenoid 6b is not connected.
As a result, the control device 11 stops the brake operation in 40 milliseconds based on the stored contents of the storage means, and if there is a forward pedal depression signal, outputs a thread removal signal as shown by the broken line in FIG. Without,
It is possible to immediately output a sewing machine operation signal and start sewing work.

[Effect] As described above, the present invention detects whether or not the yarn removing device is connected to the output circuit of the control device,
If the thread wiper is connected, even if you operate the operating member to restart sewing, the output of the signal for re-driving the thread wiper will be delayed until the thread wiper returns to its normal position, so the needle and thread will be Sewing work can be resumed safely without interference with the cleaning device. Further, when the thread removing device is not connected, the sewing operation can be resumed promptly in response to the above-mentioned operation of the operating member without waiting for the time corresponding to the operation of the thread removing device. Therefore, it is possible to select whether or not to use the thread removal device depending on the sewing work, and when it is not used, it is possible to reduce waiting time and improve work efficiency.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram of the sewing machine of this invention, Fig. 2
The figure shows a specific circuit diagram of an electromagnetic solenoid drive circuit and a detection device in the thread removing device, FIG. 3 is a signal waveform diagram, and FIG. 4 is a flowchart. Explanation of symbols, 2... Drive device, 4... Hand, 5...
... Thread cutting device, 6 ... Thread removing device, 6a ... Wiper, 6b ... Electromagnetic solenoid, 7 ... Operation member (pedal), 11 ... Control device, 12 ... Detection device.

Claims (1)

[Scope of Claims] 1. A drive device that moves the needle up and down with respect to the object to be sewn, a thread cutting device that cuts the thread that contributes to sewing under the object to be sewn, and a cut end of the thread on the needle side after cutting. a thread removing device that moves the thread over the workpiece; a thread removing device that outputs a signal for controlling driving and stopping of the driving device in response to the operation of an arbitrarily operable operating member; A control device capable of outputting drive signals for a thread cutting device and a thread removing device, and a detection device detecting whether or not the thread removing device is connected to an output circuit of the control device, When the thread removing device is connected to an output circuit, the control device is configured to prevent the thread removing device from returning to its normal position even if an operating member is operated to drive the drive device again based on the output of the detection device. the output of the signal for re-driving is delayed until the thread removal device is connected to the output circuit, and the drive device is controlled to start operating in response to the operation of the operating member. Featured sewing machine. 2. The sewing machine according to claim 1, wherein the thread removing device is connected to an output circuit of a control device via a switch that can be opened and closed arbitrarily.