JPH0220546B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a tension control method in an automatic winder.

[Conventional technology]

The spinning bobbin produced by a spinning machine, especially a ring spinning machine, is fed to an automatic winder in the next process, where it is rewound and yarn defects contained in the yarn are removed, and a package with a predetermined yarn amount and shape is created. will be rewound.

That is, in an automatic winder in which one or more winding units are arranged in parallel, yarn is pulled out from a spinning bobbin supplied to a predetermined position of each winding unit by various supply means, and the yarn is passed through a tension device, a slab, etc. After passing through a catcher, etc., it is wound onto a package rotating by a traversing drum.
To obtain one package, usually several to several dozen spinning bobbins are supplied and wound.

[Problem that the invention seeks to solve]

In such a winder, the yarn pulled out from the spinning bobbin on the yarn feeding side is pulled upward in the axial direction of the bobbin, so the yarn separated from the yarn layer runs while ballooning.

There is no problem if the spinning bobbin has a sufficient yarn layer, but as the winding progresses and the yarn layer decreases, due to the winding process in the spinning machine, the decreased yarn layer Y1 is shown in the first figure. The yarn Y is located at the lower end of the winding tube B as shown in FIG. However, due to friction between the yarns, contact with the winding tube, etc., tension is generated in the running yarn due to excessive resistance, and as a result, yarn breakage may occur. Yarn breakage as described above becomes more likely to occur as the speed of the traveling yarn increases.

Therefore, each time the yarn is cut, the winding stops for the yarn splicing operation, and especially since the amount of yarn per spinning bobbin is at most 100-odd grams, it takes a long time to produce one full package. A large number of spinning bobbins are supplied, and the occurrence of yarn breakage as described above for each bobbin causes a reduction in the operating efficiency of the winder.

The present invention aims to solve the above problems.

[Means for solving the problem] The present invention includes a tension sensor that detects the tension of the running yarn for each winding unit;
A tension device for controlling the tension of the thread based on a yarn tension fluctuation signal generated by the tension sensor and a winding control means for controlling the winding speed of the thread based on the signal from the tension sensor are provided. The winding speed is controlled by the action of the winding control means when the tension exceeds a controllable tension range that can be controlled only by the device.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of a winding unit U constituting an automatic winder. The yarn Y unraveled and pulled out from the spinning bobbin 1 passes through a balloon breaker 2 and a tension device 3, and is checked for yarn defects by a yarn defect detection head 4 such as a slab catcher, while a package 6 is rotated by a traversing drum 5. It is wound up.

During winding, the variation in the thickness of the yarn passing through the slab catcher 4 is input to the clearer controller 8 as an electrical signal 7, and by comparing it with a reference value, if it exceeds the allowable range, the yarn will pass through the defective part. The controller 8 immediately outputs a command signal 10 to the cutter drive device 9.
The cutter operates and forcibly cuts the thread.
Along with the thread cutting, the thread running signal 11 from the slab catcher 4 is turned off, and thread breakage is detected.
A command to stop the traverse drum drive motor 12 is issued from the controller 8, and the rotation of the drum 5 is stopped.
Subsequently, a command signal is outputted from the controller 8 to start the yarn splicing operation by the yarn splicing device 13, and the yarn splicing is performed by a known yarn splicing means.

Reference numeral 14 in FIG. 1 is a pulse generator for detecting the rotation of the traversing drum 5. For example, it consists of a magnet fixed to a part of the end face of the drum and a proximity sensor. Applies to constant length mechanisms to be calculated.

Furthermore, in FIG. 1, the rotational speed of the drum drive motor 12 provided in each winding unit is controlled by an inverter 15 provided in each winding unit. That is, each winding unit U is equipped with a control device 16 (described later) for controlling the motor to the most suitable rotational speed based on the winding situation of each unit, and a control signal 17 outputted from the control device 16 is used to control the motor. Thus, the rotational speed of the drum motor 12 is set via the inverter 15.

An example of the tension device 3 is shown in FIGS. 2 and 3. In FIG. 2, two disks 18a and 18b are shown, one of which is fixed and the other is pressed against it.
In the forming tension device 18 which holds the yarn Y between, a movable disk 18a is swingably supported by a support arm 20, and a swinging rod 19 swings by the forward and reverse rotation of a rotary solenoid SO1, and The spring 21 is suspended by locking both ends to the support arm 20, and the swinging rod 19 is swung by the forward and reverse rotation of the rotary solenoid SO1.
The tension of the running system Y is controlled from time to time by increasing or decreasing the unloading force of 1, thereby changing the pressing force between the two disks 18a and 18b.

In the example of the tension device 26 shown in FIG. 3, the side surfaces have corrugated concave and convex surfaces 22 that engage with each other, and the top of each wave is provided with a plurality of short rods 23 that protrude perpendicularly to the direction of the waves. gate plates 24a, 24
b, and a drive mechanism 25 that moves one gate plate 24a back and forth by rotation of a rotary solenoid SO2 to increase or decrease the amount of engagement of the waveform uneven surface. As the gate plate 24a moves back and forth, the tension of the running yarn Y is sequentially controlled by changing the surface of contact with the short rod as the yarn Y bends and travels in a zigzag manner on the surface of the short rod 23.

The tension sensor 26 shown in FIG. 1 is a sensor using a piezoelectric element installed at a position where the thread at the end of the traverse comes into pressure contact with the tension sensor 26.

FIG. 4 is a block diagram of the control device 16 shown in FIG. Ru. Furthermore, the output of the low-pass filter 29 is the differential amplifier 3.
0, common mode noise is removed, and the signal is sent to the half-wave rectifier circuit 31. The half-wave rectifier circuit 31 extracts only the component applied to the sensor head as thread tension. The output of the half-wave rectifier circuit 31 is input to an averaging element 32 and averaged. The averaged signal is sent to a sample hold circuit 33 and an A/D converter 34.

The CPU 35 periodically samples and holds the circuit 3.
3 and the A/D converter 34 to read the tension value. Compare and calculate the difference with the reference tension value 36 inputted from the reading result,
Data is output 37 to the tensor control device.

That is, when the reference tension value<the current tension, the tensioner control output value is decreased, the thread nipping force of the tensioner is decreased, and the tension is lowered. Further, when the reference tension value is greater than the current tension, the tensioner control output value is increased, the thread nipping force of the tensioner is increased, and the tension is increased. Note that when the reference tension value=current tension, the tensor control output value remains unchanged.
The output data output from the CPU 35 is isolated by a photocoupler 38 and then converted into an analog signal (voltage) by a D/A converter 39. This voltage is converted into a current by the V/I converter 40, which drives a rotary solenoid (SO1 in FIG. 2) for tensor adjustment, thereby controlling the yarn nipping force. Control is continued by repeating such control so that the tension falls within the reference tension range.

On the other hand, even with the above tension control,
When the tension increases, that is, when it exceeds a controllable tension range in which the tension increases even though the tensioner's nip force is set to zero, the yarn running speed is controlled. That is,
Controlling the driving motor 12 of the traversing drum 5 via the inverter 15 from the control device 16 shown in the first diagram,
This reduces the rotation speed.

The relationship among the tension fluctuation, tensioner nip force, and yarn speed is shown in FIGS. 5 to 7. In Figure 5, the tension changes when unwinding and winding the thread from one bobbin are approximately as shown in the figure, and at the beginning of winding t.
When the winding speed is changed from 0 to a constant winding speed, the tension is almost constant, and as the yarn layer on the bobbin decreases, the tension gradually increases, and near the end there is a tendency for the tension to increase rapidly as described above. Therefore, if the yarn speed is lowered from the point t2 where the tension suddenly increases, the tension will also decrease in accordance with the amount of decrease in the yarn speed, but reducing the winding speed is not preferable from the point of view of the operating efficiency of the entire winder. Therefore, in the present invention, the tension is controlled by reducing the nip force C of the tensioner without reducing the yarn speed within a certain period of time from the tension increase point t2. That is, the tension is controlled by the tension device 3 between time t2 and t3, and between time t3 and t5.
At this point, the tension device is already open and tension control is no longer possible with the tension device, and tension control is performed for the first time during this period by reducing the yarn speed D.

In Figures 5 and 6, the reason why the nip force is changed from time t0 to t1 is because the tension is small at the beginning of winding, so the yarn tends to gather near the center of the package cage due to centrifugal force. In order to prevent such twill misalignment, the nip force is greater than the nip force during normal winding during time t0 to t1, thereby compensating for the lack of tension at the start of the winding.

Furthermore, during constant speed winding between time t1 and t2, the yarn speed is constant F as shown in FIG. 7, but the tension changes as the winding progresses as shown in FIG. As the thread layer decreases, the tension tends to increase (G). Therefore, during this period, the nip force of the tension device is gradually reduced (H).
That's what I'm doing.

〔Effect of the invention〕

As described above, in the present invention, even in the tension increasing range, the yarn speed can be maintained as low as possible without reducing the yarn speed.
The yarn tension is controlled by a tension device, and tension control is performed by lowering the yarn speed only when the tension exceeds the controllable tension range of the tension device, so overall the yarn speed is maintained at a normal winding speed. By maintaining the speed, it is avoided to reduce the operating efficiency of the winder, especially from 1000 to
It has a remarkable effect on high speed winders of 2000m/min.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing an example of a winding unit that implements the method of the present invention, FIG. 2 is a perspective view showing an example of a tension device, FIG. 3 is a perspective view showing another example, and FIG. 4 5 is a block diagram showing an example of the control device 16, FIG. 5 is a line diagram showing one pattern of thread tension fluctuation when rewinding one bobbin, and FIG. 6 is a diagram showing a nip force showing the tension control method of the present invention. FIG. 7 is a yarn speed diagram showing the same method. U...winding unit, 12...motor, 15...inverter, 16...control device, 1
8, 26... tension device, 27... tension sensor.

Claims (1)

[Claims] 1. A tension sensor that detects the tension of the running yarn for each winding unit, and a tension device that controls the yarn tension based on the yarn tension fluctuation signal generated by the sensor.
and a winding speed control means for controlling the winding speed of the yarn based on the signal of the tension sensor, and when the tension exceeds a controllable tension range that can be controlled only by the tension device, the winding speed control means A tension control method in an automatic winder, characterized in that the winding speed is controlled by the action of.