JPS5913876B2 - Industrial sewing machine control device - Google Patents

Description

[Detailed description of the invention] The present invention relates to a control device for an industrial sewing machine.

In conventional sewing machine operation, the sewing machine rotates even when the front foot switch is momentarily turned on, so if the foot switch is accidentally stepped on instantly, or when only the presser foot is lowered using the front foot switch. This is inconvenient if you want to do so.

This will be explained according to FIGS. 1 and 2.

FIG. 1 shows a schematic structure of a sewing machine, particularly a general industrial sewing machine, in which a main body 1 of the sewing machine is mounted on a table 2, and a motor 3 is mounted below.

The main body 1 is provided with a presser foot lifter 4 for pressing the cloth, a driving pulley 5, and a speed generator 6 for detecting the number of rotations and a detector 7 for detecting the position of the sewing machine needle.

Next, a belt 9' is applied to the pulley 5 and a pulley 8 attached to the shaft of the motor 3, and a transmission mechanism 9 that connects and disconnects the rotational force of the motor 3 to the pulley 8 is provided, and the sewing machine including this transmission mechanism operates. A controller 10 for controlling the sewing machine is provided, and a sewing command is given to the controller 10 by a foot switch 11.

Now, when you step on the foot switch 11 forward, the controller 10
When the front pedal switch (not shown) inside is turned on, current flows through the clutch coil 12 shown in FIG. 2, and the clutch plate 13 is coupled with the clutch friction plate 14 fixed to the shaft of the motor 3.
The rotational force of the motor 3 rotates the sewing machine via the pulley 8, the belt pulley, and the pulley 5.

This rotational speed is detected by a speed generator 6, the position of the sewing machine needle is detected by a detector 7, and each output detection signal is sent to a controller 10 to perform necessary sewing machine operation control.

That is, the number of rotations of the sewing machine is controlled in accordance with the amount of depression of the foot switch 11, and the sewing machine is stopped at a specific position based on a signal indicating the position of the sewing machine needle.

To rotate the sewing machine to a specific rotation speed, the controller 10 controls the current flowing through the clutch coil 12 or the brake coil 15 (Fig. 2), and to stop the needle of the sewing machine at a specific position, the detection This is done by using the signal obtained from the device 7.

In other words, when the needle of the sewing machine reaches a predetermined position, the controller 10
The brake coil 15 is energized, the clutch plate 13 is coupled to the brake friction plate 16, and the pulley 8 stops rotating, thereby stopping the needle at a predetermined position.

In this way, the sewing machine performs the necessary rotations and stops.

A normal industrial sewing machine is equipped with thread trimming, thread sweeping, and presser foot lifting mechanisms, and when the foot switch 11 is stepped forward and the front switch in the controller 10 is turned on, the presser foot lifter 4 is lowered and sewing begins. do.

Then, when you step on the foot switch 11, the controller 1
The reverse treadle switch in 0 is turned on, and a series of sewing machine operations including thread trimming, thread sweeping, and presser foot lifting are performed.

That is, when the thread is cut by the thread trimmer and the cut thread is swept away by the thread wiper, the presser foot lifter 4 is then lifted, the presser foot on the cloth is released and the cloth can be moved freely manually.

Conventionally, when the front pedal switch is turned on again after the above operation is performed, the presser foot lifter 4 is lowered and the clutch coil 12 is energized, so that the sewing machine starts rotating, even if it is an instantaneous ON operation. The needle rotates until it is in position again (usually one revolution).

Therefore, inconveniences occur when the foot switch 11 is accidentally stepped on instantaneously, or when an attempt is made to lower only the presser foot lifter using the front foot switch.

For example, when it is desired to check the needle position by pressing the cloth and lowering the needle, unnecessary rotations of the sewing machine are performed.

This invention was made to solve the problems of the conventional sewing machine control mechanism, and when the presser foot is being raised, the presser foot is only raised by turning on the front pedal switch momentarily. An object of the present invention is to provide a control device for an industrial sewing machine that operates so that the sewing machine moves downward.

In this control device, when the front foot switch is turned on during the operation of lifting the presser foot, the presser foot lifter is lowered, and then it is checked again whether the front foot switch is turned on.

Hereinafter, this invention will be explained in detail with reference to Examples.

FIG. 3 shows an example of a control circuit used in the present invention. According to this control circuit, the presser foot lifting instruction signal 21 and front pedal switch signal 22 generated in the controller 10 are processed to move the presser foot lifter 4 up and down. A presser foot lifting signal 24 and a drive signal 28 for rotating the sewing machine are output.

That is, when the presser foot lifting instruction signal 21 is input to the flip-flop circuit 23 after the reverse pedal switch is turned on and thread trimming and thread sweeping are performed, this flip-flop circuit 23
is set and outputs presser foot lifting signal 24, presser foot lifting 4
will rise.

Now, if the front pedal switch is turned on during this upward movement, the front pedal switch signal 22 is input, and the flip-flop circuit 23 is input.
is reset, the presser foot lifter signal 24 is turned off and the presser foot lifter 4 is lowered.

At this time, the timer circuit 25 is activated by the fall of the presser foot lifter signal 24, and generates a pulse that lasts longer than the time required for the presser foot lifter 4 to descend, and its output signal is inverted by the inverter circuit 26 and then logically multiplied. circuit 27
Enter.

Therefore, while this signal is input to the AND circuit 27, even if the front switch signal 22 is output from the foot switch 11, the drive signal 28 is not output, so the sewing machine does not rotate.

If the front pedal switch signal 22 is still output after the timer circuit 25 times up, the drive signal 28 is output,
The sewing machine rotates.

Therefore, when the on-time of the front foot switch signal 22 is shorter than the duration of the output pulse of the timer circuit 25, only the presser foot lifter 4 is lowered and the sewing machine does not rotate.

As explained above, according to the present invention, the presser foot lifter can be lowered by instantaneously turning on the front foot switch, so when it is desired to lower only the presser foot lifter, the front foot switch is turned on instantaneously. Just do it.

Therefore, the ease of use of the industrial sewing machine can be significantly increased.

Although the switches have been described as foot-depressing, forward-depressing, and reverse-depressing switches, it goes without saying that the switch is not limited to these, and any switch having the same effect may be used.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is a perspective view showing a schematic configuration of an industrial sewing machine, Fig. 2 is a schematic diagram of a rotational force transmission mechanism of a motor, and Fig. 3 is an embodiment of a control circuit used in the present invention. FIG. 1...Body, 2...Table, 3...
...Motor, 4...Presser foot lifter, 6...
...Speed generator, 7...Detector, 9...
・Transmission mechanism, 10...Controller, 11...
・Foot switch, 21... Presser foot lifting instruction signal, 22... Front pedal switch signal, 23-=...
...Flip-flop circuit, 24...Presser foot lifting signal, 25...Timer circuit, 26...
・Inverter circuit, 27...AND circuit, 28
・・・・・・Drive signal.

Claims (1)

[Claims] 1. A driving signal for the sewing machine and a lowering operation signal for the presser foot are outputted according to a front pressing signal of the foot switch, and a raising signal for lifting the presser foot is outputted according to a reverse pressing signal of the foot switch, and the above-mentioned outputs are In a machine configured to operate each mechanism of the sewing machine accordingly, if the front pedal switch outputs a front pedal signal while the presser foot lifter is rising, a command signal for lowering the presser foot lifter is output. At the same time, a timer circuit is configured to start operating for a predetermined time slightly longer than the required descending time for lifting the presser foot, and while this timer circuit is operating, the sewing machine drive signal is not output even if the front pedal signal is output. 1. A control device for an industrial sewing machine, characterized in that the controller is configured to output no output, and to output a sewing machine drive signal if there is a front pedal signal after the timer circuit has finished operating.