JPH0647183A - Bobbin for bobbin thread of sewing machine, bobbin thread remainder detecting device, and bobbin thread winding device - Google Patents

Abstract

PURPOSE:To provide a bobbin thread remainder detecting device of a sewing machine having high detection precision and a bobbin and a bobbin thread winding device allowing the detection. CONSTITUTION:A bobbin 1 having a mark and a hole 1b on the end face of a flange is employed, initial winding is applied to the bobbin 1, then a thread pressing wire 8 is inserted into the hole 1b, and winding is reversed. The bobbin thread is wound, the rotation direction of the bobbin 1 fitted to a shuttle is judged based on the output signals of two detecting sensors, and a report signal is generated when the rotation direction is reversed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bobbin thread remaining amount detecting device capable of detecting a bobbin thread remaining amount while a bobbin is accommodated in a sewing machine hook, a bobbin suitable for the detection, and a bobbin thread winding device. Is.

[0002]

2. Description of the Related Art A bobbin thread remaining amount detecting device for a sewing machine has been conventionally provided by a mechanical stylus (Japanese Patent Publication No. 61-43075)
No.) and an optical sensor (Actual exploitation 64-6478)
No. 3) etc. are known. The mechanical stylus detects the thickness of the residual thread layer by passing the stylus through the opening on the peripheral side of the shuttle and bringing its tip into contact with the bobbin winding base mounted on the shuttle. With the sensor, an opening is provided in one end of the shuttle and the flange of the bobbin housed inside, and an optical sensor is arranged toward the opening so that the light beam is opened when it falls below a predetermined bobbin thread residual thread layer. To detect that the residual yarn layer is small.

[0003]

Both the above-mentioned lower thread remaining amount detecting device using a mechanical stylus and the lower thread remaining amount detecting device using an optical sensor have a drawback that the measurement accuracy is low.

It is an object of the present invention to provide a bobbin thread remaining amount detecting device for a sewing machine having high detection accuracy, a bobbin and a bobbin thread winding device capable of detecting the same.

[0005]

In order to achieve the above object, a bobbin for bobbin thread of a sewing machine of the present invention is provided with a single mark or a plurality of marks at equal intervals from the center of the flange end face, and The bobbin thread remaining amount detecting device has a plurality of holes drilled at the opposite positions of the flange, and the bobbin thread remaining amount detecting device can detect one or more marks on the flange of the detected bobbin mounted on the shuttle. It has a plurality of detection sensors arranged at intervals different from the above, and it determines the rotation direction of the bobbin to be detected by the output signal and issues a notification signal when the rotation direction is reversed. The device consists of a bobbin shaft that rotates non-rotatably when the bobbin to be detected is rotated, a thread pressing wire that is inserted through a hole in the flange of the bobbin to be detected when stopping the normal rotation, and a bobbin shaft normal Turning Consisting of an encoder that reads the number, when the read value reaches a preset value, the bobbin shaft stops rotating normally and the bobbin shaft starts rotating backward by inserting the thread presser wire into the bobbin hole to be detected. It is a thing.

[0006]

[Operation] In the bobbin thread remaining amount detecting device of the sewing machine configured as described above, the bobbin of the present invention in which the bobbin thread is wound by the bobbin thread winding device of the present invention is attached to the sewing machine hook and sewing work is performed. When performing, the rotation direction is determined by the signal output from each detection sensor, and when the rotation direction is reversed, a notification signal is issued. Further, in the bobbin winding device of the sewing machine, when the bobbin of the present invention is attached to the bobbin shaft and the yarn end of the cone is wound and rotated in the normal direction, the encoder reads the rotation and reaches a preset value to reach the bobbin. Axis rotation stops. As a result, the thread retainer wire is inserted into the bobbin hole, the bobbin shaft starts to rotate in reverse based on the signal from the controller, and the thread that was wound in the previous step is prevented from being unwound by the thread retainer wire and is wound in the opposite direction. To be

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a bobbin used in a lower thread remaining amount detecting device and a lower thread winding device will be described with reference to FIG.

In this bobbin 1, two marks 1a of a color or the like which can be clearly discriminated from the ground color of the end surface or a magnetic material are attached to the end surface of one flange at equal distances from the axis of the bobbin, In addition, a guide pin 1 of the bobbin winding device described later.
1 and positioning hole 1b corresponding to the thread pressing wire 8
Are formed so as to face both flanges.

The bobbin 1 is subjected to initial winding with a small number of windings and subsequent main winding in the reverse direction by a bobbin winding device described later.

Next, the bobbin thread remaining amount detecting device will be described with reference to FIGS.

This bobbin thread remaining amount detecting device comprises a detection sensor (D ₁ ) 2, a detection sensor (D ₂ ) 3 and a discrimination circuit 4 shown in FIG.

2 and 3 are operation explanatory views showing the outline of the bobbin 1 and the respective detection sensors 2 and 3 mounted on the horizontal shuttle and the vertical shuttle, respectively. The shuttle, its peripheral portion, sensor holder and the like. Is omitted.

The detection sensors 2 and 3 are, for example, reflection type optical sensors that receive the reflected light of the projected light and send a signal to the discrimination circuit 4. And each detection sensor 2,
3 are arranged at equal distances from the axis of the bobbin 1 around which the bobbin to be detected is wound so that the mark 1a can be detected. The interval is different from the interval between the marks 1a and 1a so that the marks 1a and 1a that move due to the rotation of the bobbin 1 are detected with a time shift. High and low signals are issued from these detection sensors 2 and 3 in response to the movement of the mark 1a due to the rotation of the bobbin 1. Incidentally, instead of the reflective optical sensor described here,
A magnetic sensor, an ultrasonic sensor or the like may be adopted. In that case, needless to say, it is necessary to change the mark 1a of the bobbin 1 to one suitable for them. The example in which two marks are provided has been described above, but the number of marks may be one. In that case, the detection timing is slightly later than in the two cases.

The discriminating circuit 4 is as schematically shown in FIG. 4, in which the detection sensors 2 and 3 have Schmitt circuits 41 and 4 respectively.
2, inverter 43, flip-flop 44, 4
5, the NAND circuits 46 and 47, and the oscillator 48 are connected as shown.

When the bobbin 1 in which the initial winding with a small number of windings and the subsequent main winding of both of the yarns for normal use in the reverse direction are carried on is attached to the hook of the sewing machine and sewing is performed, the bobbin 1 is The rotation of cw or ccw causes intermittent rotation in the fixed direction. The determination circuit 4 determines the rotation direction of the bobbin 1 depending on which of the detection sensors 2 and 3 outputs the signal first. Then, the determination signal is sent to and stored in a controller (not shown).

When the bobbin 1 delivered from the bobbin 1 reaches the winding direction reversal position of the initial winding portion as the sewing operation proceeds, the bobbin 1 is rotated by the bobbin thread by the initial rotation direction cw or ccw. To ccw or cw. At this time, the signal related to the rotation direction sent from the determination circuit 4 to the controller is the opposite of the initial one, and the controller that has received the signal is a signal for informing such as blinking of the pilot lamp. Is emitted. In response to this, the worker will perform necessary work such as bobbin replacement. At this point, if the remaining amount of the bobbin thread is L, the number of windings from the beginning of winding to reversal is N, and the diameter of the bobbin winding base is d, then L = π · d · N, and the remaining amount of the lower thread is You can know exactly.

Next, the lower thread winding device will be described with reference to FIGS.

In this bobbin winding device, generally, a bobbin 1 around which a bobbin thread to be detected is wound is mounted and a motor 6 is installed.
The bobbin shaft 5 is driven by the shifter 7, the shifter 7 is provided with the thread pressing wire 8 that is inserted into the positioning hole 1b of the flange of the bobbin 1, and the encoder 9 that measures the rotation of the bobbin shaft 5.

The bobbin shaft 5 is rotatably supported by the bearing 10, and the support plate 1 is provided with a guide pin 11 corresponding to the positioning hole 1b of the bobbin 1 projecting behind the bobbin mounting portion at the tip.
2 is fixed. Further, the support plate 12 is provided with a hole 12a through which the thread pressing wire 8 is inserted.

The shifter 7 is movable on the bobbin shaft 5 between the bearing 10 and the support plate 12 in the axial direction of the bobbin shaft 5 by a key 13 provided on the bobbin shaft 5, and the bobbin shaft 5 is also movable.
It is rotatably supported together with. In the vicinity of the bobbin shaft 5, an intermediate portion is swingably supported by a lever bearing 14, one end is pivotally attached to a push-pull solenoid 15, and
A shift lever 16 biased by a return spring 17 is provided, and a roller 16a at its free end is engaged with a circumferential groove 7a of the shifter 7. Therefore, when the push-pull solenoid 15 is pulled, the shifter 7 advances to the left, the thread pressing wire 8 is inserted through the hole 12a of the support plate 12 and the positioning hole 1b of the bobbin 1, and the push-pull solenoid 15 is pushed. Then, the shifter 7 retracts to the right and the thread pressing wire 8 is pulled out from the bobbin thread Th.
The push-pull solenoid 15 is normally in a push state and is in a standby state. When the forward rotation of the motor 6 is stopped, the push-pull solenoid 15 is brought into a pull state, and the transition to the pull state causes the motor 6 to reversely rotate based on a signal from the controller 24. To do. After that, the motor 6 is stopped by a signal from a reflection sensor 23 described later, and at the same time, the motor 6 is in a push state. The thread pressing wire 8 is fixed to the shifter 7 with a set screw 18.

The bobbin shaft 5, the rotating shaft of the motor 6 and the shaft of the encoder 9 are respectively provided with sprockets 19 and 2.
0 and 21 are fixed, and a timing belt 22 is stretched around them. Therefore, the encoder 9 can indirectly measure the rotation of the bobbin shaft 5. The read signal of the encoder 9 is sent to a preset counter in the controller 24, and when the count number reaches a preset number of initial windings, the motor 6 is stopped.

A reflection sensor 23 is provided near the peripheral side surface of the bobbin 1. This is because the full-scale winding of the bobbin thread on the bobbin 1 progresses and the fact that the thread layer has reached a predetermined thickness set in advance is stopped, and the motor 6 is stopped and the push-pull solenoid 15 Is operated to push the thread pressing wire 8 out of the bobbin 1 and the winding pilot lamp 25 is turned on.

The explanation was changed, but the controller 24
Controls the operation of each of the above-mentioned members, and as shown in FIG. 6, in addition to the motor 6, the encoder 9, the push-pull solenoid 15, the reflection sensor 23, the pilot lamp 25, the start switch 26 and the encoder 9. A preset switch 27 for presetting the read value is connected. Then, the exchange of signals between the respective members is performed via the controller 24.

The operation timing of the bobbin thread winding device thus constructed will be described with reference to FIG. The arrow shown by the dotted line in the figure indicates that the signal at the source of the arrow is the activation signal for the operation at the destination of the arrow.

The guide pin 11 is attached to the positioning hole 1 of the bobbin 1.
The bobbin 1 is mounted on the bobbin shaft 5 so as to be aligned with b, and the thread end of the cone (not shown) is attached to the bobbin 1 by 2-3.
When the start switch 26 is pressed after being wound, the motor 6 rotates in the normal direction and the encoder 9 reads the rotation of the bobbin shaft 5. When the number of read rotations reaches a preset number, the rotation of the motor 6 is stopped based on a signal from the controller 24. In response to the stop signal of the motor 6, the push-pull solenoid 15 is in the pull state,
The shifter 7 advances through the shift lever 16, the thread pressing wire 8 is inserted from the positioning hole 1b of the bobbin 1 so as to contact the upper surface of the thread, and reaches the positioning hole 1b on the opposite side. When the motor 6 rotates in the reverse direction based on the signal from the controller 24 due to the shift of the push-pull solenoid 15 to the pull state, the yarn wound in the previous step is prevented from being unwound by the yarn pressing wire 8, and the bobbin 1
Is wound in the opposite direction to the previous step. When the winding progresses and the yarn layer of the bobbin 1 reaches a predetermined thickness set in advance, a signal is emitted from the reflection sensor 23, the motor 6 stops, and the push-pull solenoid 1
5 moves to the push side and the thread presser wire 8 moves to the bobbin 1
And the winding pilot lamp 25 lights up,
The worker is notified. Further, by pressing the preset switch 27 and selectively setting the displayed numerical value, it is possible to perform a predetermined initial winding by comparing with the count signal of the encoder 9.

[0026]

Since the present invention is configured as described above, it has the following effects.

That is, by adopting the bobbin having the mark and the hole for inserting the thread pressing wire for preventing the unwinding at the time of reversing the winding, the main winding can be reversed with respect to the initial winding. became. Further, by adopting a bobbin wound with such a bobbin thread and detecting the winding reversal portion, the bobbin thread remaining amount can be known very accurately.

[Brief description of drawings]

FIG. 1 is a perspective view of a bobbin of the present invention.

FIG. 2 is a schematic operation explanatory diagram of a lower thread remaining amount detecting device of the present invention, which targets a lower thread of a bobbin attached to a horizontal shuttle.

FIG. 3 is a schematic operation explanatory view of a lower thread remaining amount detecting device of the present invention, which targets a lower thread of a bobbin attached to a vertical shuttle.

FIG. 4 is a schematic diagram of a determination circuit used in the lower thread remaining amount detection device of the present invention.

FIG. 5 is a cross-sectional view showing the mechanism of the bobbin thread winding device of the present invention.

FIG. 6 is a block diagram of the bobbin winding device according to the present invention.

FIG. 7 is a diagram showing an operation timing in the lower thread winding device of the present invention.

[Explanation of symbols]

 1 bobbin 1a mark 1b hole 2 detection sensor 3 detection sensor 4 discrimination circuit 5 bobbin shaft 8 thread presser wire 9 encoder

Claims (3)

[Claims] 1. A bobbin for bobbin thread of a sewing machine, wherein one or a plurality of marks are provided at equal distances from the center of the flange end face, and a plurality of holes are formed at opposing positions of each flange. 2. A bobbin attached to a hook has a plurality of detection sensors arranged at a position different from an interval between the marks at a position where one or a plurality of marks on a flange of the bobbin to be detected can be detected. A bobbin thread remaining amount detecting device for a sewing machine, which determines a rotation direction of a detection bobbin and issues a notification signal when the rotation direction is reversed. 3. A bobbin to be detected is mounted non-rotatably,
A bobbin shaft that rotates in the reverse direction, and a thread pressing wire that is inserted through a hole in the flange of the bobbin to be detected when stopping the normal rotation,
It consists of an encoder that reads the number of forward rotations of the bobbin shaft.When the read value reaches a preset value, normal rotation of the bobbin shaft is stopped and the bobbin shaft is inserted by inserting the thread presser wire into the detected bobbin hole. The bobbin thread winding device for sewing machines that starts reversing.