JPS5810548Y2 - 2-needle sewing device - Google Patents

Description

[Detailed explanation of the invention] This invention changes from two-needle operation to one-needle operation or one-needle operation.
This invention relates to a two-needle sewing device that performs sewing by switching from a single-needle operation to a two-needle operation.

With this type of conventional device, when sewing the corners of a workpiece, manually switch from two needles to one needle, rotate the sewing machine at low speed, and sew one stitch for a certain number of stitches. Furthermore, when transitioning from single-needle sewing to double-needle sewing, the switch from single-needle to double-needle sewing was also performed manually.

However, when sewing with frequent manual switching as described above, there are disadvantages in that it not only causes fatigue for the sewing worker, but also requires advanced sewing techniques and reduces work efficiency.

This idea was made in view of the above-mentioned circumstances.
When sewing the corners of the workpiece, it is possible to automatically switch between two-needle operation and single-needle operation using an electromagnet, etc., making it easy to switch between two-needle and single-needle operation with high efficiency. The present invention aims to provide a two-needle sewing device.

Hereinafter, an embodiment of this invention will be described in detail regarding the screen.

FIG. 1 shows an example of a two-needle sewing device according to the present invention. Reference numeral 1 indicates a two-needle sewing machine body, and this sewing machine body 1 is placed on a table 2 mounted on a leg 2a.

3 is a pulley attached to the rotating shaft inside the sewing machine body 1;
is an ordinary needle position detector that detects the needle position in order to stop the needle 5 in the lower position, and is attached to the sewing machine body 1 in a manner connected to the pulley 3.

Reference numeral 6 denotes a main motor for operating the two-needle sewing machine main body 1 attached to the bottom surface of the table 2 at high speed. 3a is suspended, and the two-needle sewing machine main body 1 is operated at high speed or stopped by operating a pedal 7 connected to a clutch mechanism 6a.

Reference numeral 8 indicates a needle position detector 4 that detects the needle position when stopping the operation of the two-needle sewing machine main body 1.
9 is the 2-needle sewing machine main body 1.
This control box 9 houses an operation control circuit, and this control box 9 is attached to the leg 2a.

Reference numeral 10 denotes a switching device for switching from two-needle operation to single-needle operation, or from one-needle operation to two-needle operation, as shown in FIGS. 2 to 4.
A switching device 10 is provided at both ends of an operating rod 10b connected to the upper end of the lever 10a, which is rotatably attached to the lever 10a, and has a switching device 10 in a neutral position, that is, in a clockwise direction and a counterclockwise direction from two-needle operation. Rotating electromagnets 11 and 62 are respectively connected and driven by the control circuit described above, and when the switching device 10 is in the position shown in FIG. When the needle 10 is rotated either to the left or right, single needle operation is performed.

For example, when the lever 10a is rotated clockwise as shown in FIG. 3, single-needle operation is performed using the right hand 5, and when the lever 10a is rotated counterclockwise as shown in FIG. When this happens, single-needle operation is performed using needle 5 on the left side.

Further, reference numeral 64 denotes an electromagnet 11 that is driven when corner stitching is performed.
Reference numeral 62 is a switch for selecting which electromagnet to use. When this switch 64 is turned to the left, for example, the left needle stops, and the right needle 5 stitches the corner.

5 and 6 show an example of the internal structure of the needle position detector 4. This detector 4 includes a slip ring 42 for detecting the needle top position, which is composed of a conductor portion 42a and a non-conductor portion 42b. and a needle down position detection slip ring 43 having a conductor portion 43a and a non-conductor portion 43b, each of these slip rings is connected to a common shaft 47 connected to the pulley 3.
each slip ring 42.
．． 43 has carbon brushes 44 and 46 that come in sliding contact with each other.
and a carbon brush 45 that makes common sliding contact across both.
are in contact with each other, and each of these carbon brushes is held by an insulating block 70.

Further, FIG. 7 shows an example of a control circuit according to this invention, in which waveform shaping circuits 20 and 21 are connected to each carbon fiber 44 and 46 of slip rings 42 and 43 in the needle position detector 4, respectively. A (+)E power supply is connected to the input sides of these shaping circuits 20 and 21 via resistors 60 and 61.

As a result, the carbon brush 45 in the slip ring 42. The circuit connecting the conductor part 42a and the carbon brush 44 is electrically connected when the needle 5 is in a position other than the upper position, but when the needle 5 is in the upper position, the circuit is opened by the non-conductor part 42b. Therefore, from the resistor 60 to the carbon brush 44. The current flowing to the ground through the conductor portion 42a and the carbon fiber 45 flows to the input side of the shaping circuit 20, a high voltage signal is applied to the input side of the shaping circuit 20, and output 1 is sent to its output side. .

Similarly, when the needle 5 is at the lower position, the carbon brush 46 on the slip ring 43. Conductor part 43a
and a circuit formed by the bomb brush 45 is opened, and a high voltage signal from the E power source is applied to the input side of the shaping circuit 21 to send out an output 1 at its output side.

Furthermore, the output side of the waveform shaping circuit 20 is an AND gate 2.
4 to the clock input terminal of the counter 27,
The counter 27 counts how many times the input voltage to the shaping circuit 20 changes due to the rotation of the slip ring 42 and outputs the result in decimal format.
A selection switch 12 for selecting the number of stitches to be sewn at the corners of the object to be sewn is connected to the output side of the switch 12, so that the output of the counter 27 can be arbitrarily selected.

The output terminal of the waveform shaping circuit 21 is a flip-flop 31
The output Q of the flip-flop 31 is connected to the base of a transistor 50 that controls the auxiliary motor drive relay 48, and the contacts 48a and 48b of the relay 48 are connected to the three-phase AC power supply 57. A flywheel diode 49 for protecting a transistor 50 is connected in parallel to both ends of the relay 48 .

The base of a transistor 53 that controls an electromagnetic brake 51 is connected to the output Q of the flip-flop 31, and a flywheel diode 52 is connected in parallel to both ends of the electromagnetic brake 51.

Reference numeral 32 denotes a flip-flop whose reset input is the output from the selection switch 12, and its output Q serves as the set input to the free-luff 0-float 031.

Further, 33 is a flip-flop which uses the output from the selection switch 12 as a reset input via the AND gate 25, and its output Q is connected to the base of the 1-transistor 56, and the collector circuit of the transistor 56 is connected to the above-mentioned Electromagnets 11 and 62 via electromagnet selection switch 64
are connected in parallel, and flywheel diodes 55 and 63 are connected in parallel to each electromagnet 11.62, respectively.

One input of the flip-flop is used, and the output of the AND gate 26 becomes the other input of the AND gate 24 via an OR gate 28.

Further, 40 is a kickback switch connected between the (+)E power source and the ground via a resistor 36, and this switch 40 is designed so that when the motor petal is kicked back, the contact opens to enable corner sewing operation. together with the switch 40
The input terminal of the waveform shaping circuit 22 is connected to the connection point between the input terminal and the resistor 36, and when the switch 40 is turned off, the input terminal of the waveform shaping circuit 22 is
The input side of 2 is at a high potential, and the output 1 is sent to its output side, and the output is introduced as a set input of the flip-flops 32 and 33, and the other input of the OR gate 28. It is said that
It is designed to be introduced as the other manual power of the AND gate 25 via the knot circuit 34.

Further, 41 is a depressing switch that opens a contact when the pedal is depressed, which is connected between the (G) E power source and the ground via a resistor 37, and the input side of the waveform shaping circuit 23 is connected to the connection point between this switch 41 and the resistor 37. and switch 41
When OFF, the input side of the shaping circuit 23 is set to a high potential, and an output 1 is sent to its output side, so that it becomes the other power of the AND gate 26.

Next, the operation of this device constructed as described above will be explained.

When sewing the corner portions of the object to be sewn a predetermined number of times, high-speed operation with the twin needles is performed up to the angular sewing start position 100 as shown in FIG.

When the sewing progresses to this position 100, the petal stitch is operated from the neutral position 7b to the kickback position 7C shown in FIG.

This activates the kickback switch 40, its contacts open, and the input side of the waveform shaping circuit 22 becomes at a high potential.

At this time, even if a noise component is generated due to the chattering of the switch 40 as shown in Fig. 10a, this is removed by the waveform shaping circuit, and a rectangular output 1 as shown in Fig. 10 is output. Ru.

This output 1 sets the corner stitch memory flip-flop 32, and accordingly the output Q becomes 1, setting the auxiliary motor flip-flop 31.

As a result, the output Q of the flip-flop 31 becomes 1,
The transistor 50 is made conductive, the relay 48 is energized, and the contact 48a of the power circuit of the auxiliary motor 8 is turned ON, and at the same time, the flip-flop 53 is turned OFF and the brake 51 is deenergized as shown in FIG. 8.

In addition, since a set input is also introduced to the kickback memory flip-flop 33, the output Q of the flip-flop 33 is
becomes 1, and this output 1 causes transistor 56 to conduct.

Now, when the needle switching direction selection switch 64 is turned to the left as shown in FIG. 2, the transistor 56 comes to drive the electromagnet 11, so the switching lever 10 a is moved as shown in FIG. 3.
is rotated to the right, that is, counterclockwise, and the sewing machine is rotated by the single needle on the right. The driving will be as follows.

Therefore, the sewing machine operates at low speed with the single needle 5 on the right side driven by the auxiliary motor 8.

When the sewing machine is rotated at low speed, the slip ring 42 for stopping the counting position rotates and when the needle reaches the upper position, the input terminal of the waveform shaping circuit 20 is set to high potential 1, and when the needle is at a position other than the upper position, Set the ground potential to 0.

Therefore, a voltage change corresponding to the number of revolutions of the sewing machine is applied to the waveform shaping circuit 20, and at the same time, an output with a waveform as shown in FIG. Introduced to one side.

At this time, since the output of the waveform shaping circuit 22 becomes 1 by kicking back the pedal 7, the output of the OR gate 28 becomes 1 and becomes the other manual power of the AND gate 24.

Therefore, when the output of the waveform shaping circuit 20 becomes 1, the output of the AND gate 24 becomes 1.

That is, pulses having the waveform shown in FIG.

As a result, when the input voltage changes once from ground potential to high potential due to one rotation of the sewing machine, an output of 1 is sent from terminal a, indicating that the input terminal has changed once, and when the sewing machine rotates twice, the terminal Therefore, it is counted that an output of 1 is sent out and the input voltage changes twice.

Here, when the count selection switch 12 for the corner stitch section is selected to select 3 stitches, the contact point of the switch 12 is connected to the output terminal C of the counter 27.
It will be connected to.

Therefore, when the sewing machine rotates 33 times, an output 1 as shown in FIG. do.

At the same time, the flip-flop 32 is also reset, and its output Q becomes 0.

At this time, the corner stitching flip-flop 31 is not reset until the third stitch comes to the lower position.

This flip-flop 31 is a set priority flip-flop, and when the set input is 1, it is not reset even if 1 is added to the reset input as shown in FIG.
Connect the state of output 1 as shown in Figure 1f.

When the sewing machine needle 5 reaches the lower position of the third stitch, the slip ring 43 for detecting the lower position inputs the signal 1 to the reset end of the flip-flop 31 via the waveform shaping circuit 21. 31 is reset and its output Q becomes 0 (see FIG. 10 1f).

Therefore, the auxiliary motor drive relay 48 is deenergized, and the brake 51 is instead energized to stop the sewing machine at the needle down position.

By kicking back the petal as described above, the sewing machine sews only 3 stitches by running at low speed with the single needle 5 on the right side.
Sewing is performed up to the apex 200 of the corner.

At this stage, the worker changes the direction of the workpiece to 90 degrees and kicks the sewing machine back from position 7C to step position 7.
When the pedal is depressed to the point a, the depression switch 41 opens, and a waveform containing a chattering component as shown in Figure 10 is manually output to the input side of the waveform shaping circuit 23.
A signal with a rectangular waveform without chattering is output from the output side (see FIG. 10, 1f).

At this time, since the pedal lever is in the depressed state, the clutch mechanism 6a is disconnected from the auxiliary motor drive system and the main motor 6
The sewing machine is driven by a main motor 6.

Further, since the kickback switch 40 has been returned to its original closed state by the pedal pedal depression operation, the output of the waveform shaping circuit 22 becomes O.

Along with this, one input of the OR gate 28 becomes O, and the input of the flip-flop and the NOT circuit 34 also becomes 0, so the output of the NOT circuit 34 becomes 1 and is introduced into the ant game 125.

This prevents the output of the counter 27 (e in Figure 10) from being applied as a reset input to the flip-flop 33 when the kickback switch 40 is operating, and the counter 27 output only when the switch 40 is ON. This is to reset the flip-flop 33 at the output (step e in FIG. 10).

By depressing the pedal 7, the sewing machine is driven by the main motor 6, and sewing is restarted using the right single needle 5.

When the sewing machine rotates three times, the upper position detection slip ring 42, as described above, sends as many pulses as the number of rotations of the sewing machine (O in FIG. 10C) to the AND gate 24 through the waveform shaping circuit 20.

As a result, the AND gate 24 inputs the rotation signal O in FIG.

Then, as mentioned above, when the sewing machine rotates 3 times, the counter 2
An output ■ is generated at the output terminal C of 7 as shown in Figure 10 e,
Since the output is introduced into the AND gate 25, the flip-flop 33 is reset by the logical product input from the NOT circuit 34.

Therefore, the electromagnet 11 for driving the needle changer 10a is deenergized, and the lever 10a returns to the state shown in FIG. 2.

Along with this, the right side switches from one needle stitch to two needle stitches.

That is, from the corner apex 200 in FIG. 9, three stitches are sewn using one right needle, and when the sewing machine reaches position 300, it automatically switches to two-needle stitching and continues normal two-needle stitching.

During the above-mentioned double-needle sewing, the needle switching flip-flop 33 is reset and its Q output is 0, so the output of the AND gate 26 is O, and since the kickback switch 40 is also closed, the waveform is shaped. The output of the circuit 22 also becomes 0.

Therefore, the output of the OR gate 28 that takes these logical sums becomes 0, so even if one input of the AND gate 24 becomes 1, the output of the AND gate 24 will always be 0, and the counter 27 will maintain its initial state. .

That is, even if the counted position signal is input to the AND gate 24 like the force shown in FIG. 10C, the number of stitches is not counted by the counter 27.

As described above, when starting from position 100 in Fig. 9 and sewing the corners, first kick back the petal at position 7c (
8), the sewing machine will sew at low speed with the single needle selected with the needle changeover direction selection switch 64, and when the number of corner stitches set with the corner stitch number setting switch 12 has been sewn, the sewing machine will automatically sew with the needle 200 in FIG. Come to the position and stop.

At this time, the needle is stopped at the lower position, so the operator rotates the cloth around this point, and then moves the sewing machine to the same 1st position as above by operating the petal needle to the treading position 7a.
When the sewing machine is operated with a single needle and has sewn a set number of stitches, it automatically switches to double needle sewing and continues sewing.

Therefore, according to this invented device as described above, when sewing corners, simply by operating the petal, the stitch counting circuit and automatic needle switching circuit automatically change the needle and limit the rotational speed of the needle drive motor. Since the single-needle sewing operation is automatically switched and stopped, there is no need to manually operate the needle switching lever as in the past, making it possible to perform double-needle or single-needle sewing with high efficiency. At the same time, it becomes possible to perform sewing work that is easy to sew and causes less fatigue.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a sewing machine to which the sewing control system according to this invention is applied, Fig. 2 is a front view of the sewing machine showing the state during two-needle sewing in this invention, and Figs. 3 and 4 are one-needle sewing machines. A front view showing the state during needle sewing, FIG. 5 is a front view of the needle position detector in this invention, FIG. 6 is a perspective view of the needle position detector, and FIG. 7 is a control circuit diagram in this invention device. 8th
The figures are diagrams of the operation of the petal in this invention, Figure 9 is an explanatory diagram of corner sewing, and Figures 10a-m are time charts illustrating the operation of the control circuit. 1...Two-needle sewing machine body, 4...Needle position detector, 6...Main motor, 7...Petal, 8... - Auxiliary motor, 10... Needle cutting inspection device, 11.62... Electromagnet for operating needle switching device, 40.41... Switch, 12...
...Rotary switch for selecting the number of stitches, 27...
Counter, 48...Auxiliary motor control relay, 5
1...Brake coil.

Claims (1)

[Scope of utility model registration request] In a sewing machine that uses two needles for normal sewing parts and one needle for corner sewing parts, a motor that drives the sewing machine and a position detector that detects the predetermined position of the sewing machine needle, and at least two
an operating device that can be operated in one direction; a first external operation signal generated by operating the operating device in one direction; and a second external operation signal generated by operating the operating device in another direction. The signal and the position detection signal from the position detector can be counted, and a target count value can be set by external operation.
The sewing machine has an automatic switching mechanism that includes a counting circuit that generates a signal when the target set value is reached, and an electromagnetic mechanism that switches from double needle stitching to single needle stitching or from single needle stitching to double needle stitching. A device is provided, the rotation speed of the motor is set to a normal sewing speed and a predetermined speed lower than the sewing speed by an external operation signal such as a pedal, and the automatic switching device of the sewing machine is driven by the first external operation signal. Then, the sewing machine switches to single-needle sewing, stops the sewing machine needle at a predetermined position by the signal generated from the counting circuit when sewing a predetermined number of stitches, and starts the sewing machine again by the first or second external operation signal. The sewing machine is characterized by comprising a control circuit configured to deenergize the automatic switching device of the sewing machine and automatically return to double needle sewing in response to a signal generated from the counting circuit during a predetermined counting sewing. Two-needle sewing device.