JPH0280657A - Controller for stretch - Google Patents

Abstract

PURPOSE:To prevent a change in yarn properties or quality unevenness from occurring and properly control a yarn tension by calculating a stretch between nip rolls on the upstream and downstream sides in the running direction of a warp yarn and controlling the stretch in the direction to reduce deviation from the target stretch. CONSTITUTION:The target stretch is previously inputted to a stretch initial setter 16 and outputted to a stretch setter 17. During operation of a machine, an actual stretch is calculated from rotation sensors 13 and 14 by a stretch sensor 15 and the target stretch is compared with the actual stretch by a comparator 18 to drive a driver 19 in the direction to reduce deviation thereof and control the rotational direction and extent of rotation of an operating motor 9. Thereby, speed change ratio of a continuously variable transmission 3 is changed to set the stretch of a warp yarn 4 between nip rolls 5 on the upstream side and nip rolls 6 on the downstream side in the running direction of the warp yarn.

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a stretch control device for a warp sizing and drying machine.

Prior art warp sizing dryers are equipped with stretching devices to impart tension to the warp yarns in place. This stretching device applies a target stretch to the warp yarns by setting a predetermined circumferential speed between a nip roll on the upstream side and a nip roll on the downstream side in the running direction of the warp yarns.

Normally, this stretch is set as standard for high-speed driving. Therefore, during warp sizing, when the dryer is started or stopped, or during other low-speed operation, the warp tension becomes abnormally high or low even if the target stretch is set. That is, in the drying process,
As the yarn shrinks, the tension increases, which changes the yarn's physical properties and causes destruction of the desizing membrane, resulting in variations in yarn quality. Furthermore, during the sizing process, the yarn expands and stretches, reducing yarn tension, making it more likely that accidents such as yarn entanglement and yarn breakage will occur.

In this way, sizing is a drying process, and even if the stretch is set to the target value, the yarn tension will fluctuate due to changes in the warp yarn running speed, so the above! Such inconveniences occur.

OBJECTS OF THE INVENTION Therefore, it is an object of the present invention to
The purpose is to automatically change stretch according to yarn speed and manage yarn tension within an appropriate range.

Solution to the Invention In view of the above object, the present invention incorporates a tension control system in addition to a stretch control system into a stretching device, and changes the target stretch according to changes in the thread tension to maintain the thread tension at a predetermined level. I try to keep it within this range. As a result, even if the stretch is set to an appropriate value for high-speed operation, the yarn tension may be abnormally high (or not) when the yarn is operated at low speed.
Therefore, inconveniences like those of the conventional example can be prevented.

Structure of the Invention FIG. 1 shows the structure of a stretch control device 10 of the present invention in relation to a stretching device 1. As shown in FIG.

In the stretching device 1, a drive motor 2 rotates a pair of nip rolls 6 on the downstream side in the running direction of the warp yarns 4, while a continuously variable transmission 3 changes the speed of the rotation of the drive morph 2, and a pair of nip rolls 5 on the upstream side - and give the target circumferential speed ratio, that is, the target stretch between them. Note that the warp yarns 4 run between the nip rolls 5.6 via a tension roll 7 and a guide roll 8. Here, the target circumferential speed ratio, ie, stretching, is achieved by rotating the operating section of the continuously variable transmission 3, such as the operating motor 9, in either direction to change the gear ratio between the input and output of the continuously variable transmission 3. can be changed by

On the other hand, the stretch control device 10 of the present invention includes a stretch control section 11 and a tension control section 12. The stretch control unit 11 automatically sets the stretch to the target stretch by adjusting the direction and amount of rotation of the operation motor 9 according to the target stretch. Further, the tension control section 12 detects the actual tension of the warp yarns 4 at the tension roller position, and automatically changes the target stretch of the stretch control section 11 in accordance with the change in tension.

Function of the Invention Sizing is a process or a drying process, and the warp yarns 4 are urged by the rotation of the upstream nip roll 5 and the downstream nip roll 6 to run. In such a process, the stretch control unit 11 Based on their circumferential speed ratio, that is, the target stretch, the direction and amount of rotation of the operating motor 9 is adjusted, and the gear ratio of the continuously variable transmission 3 is changed, thereby achieving the target stretch between the nip rolls 5.6. Set it to the value. In this way, a stretching force (stretching force) is applied in an appropriate state for the sizing process or the drying process, and the warp yarns 4 are set at a nearly constant tension.

On the other hand, the tension control section 12 electrically detects the tension of the warp yarns 4 at the position of the tension roll 7, and automatically changes the target stretch in the stretch control section 11 according to the magnitude of the tension value. Go.

Therefore, even during low-speed operation, the tension of the warp yarns 4 does not increase or decrease abnormally, but remains within a predetermined range.

Such specific examples can be realized by each embodiment. - Example 1 (FIGS. 2 and 3) This example is an example in which when the yarn tension deviates from the upper and lower limits, the target stretch is changed to keep the yarn tension within a predetermined range.

As shown in FIG. 2, the stretch control unit 11 includes rotation detectors 13.1 each connected to the nip rolls 5.
4, a stretch detector 15 connected to these, a stretch initial setting device 16, a stretch setting device 17 connected to this, a comparator connected to the stretch detector 15 and stretch setting device 17, and this comparator 18 and is constituted by a driver 19 connected to the operating motor 9 on the output side. The tension control unit 12 also includes a tension detector 20 that detects the tension of the warp yarns 4 with a detection end 24 such as a load cell;
The comparator 21 is connected to a tension upper limit setting device 22 and a tension lower limit setting device 23.

The target stretch is manually input by stretch initializer 16 and provided to stretch setter 17 . During operation, the stretch detector 15 calculates the stretch from the rotation detector 13.14 and feeds it into one input of the comparator 18. Here, the comparator 18 compares the target stretch and the actual stretch, drives the driver 19 in the direction of decreasing the deviation based on the deviation, and controls the direction and amount of rotation of the operating motor 9. By changing the gear ratio of the continuously variable transmission 3, the stretch of the warp yarn 4 is set to a target value between the nip rolls 5 and 6.

FIG. 3 shows the relationship between the yarn speed, stretch, and yarn tension of the warp yarn 4 on the time axis.

When the stretching device 1 is in high-speed operation, the stretch control unit 11 sets the stretch to the target value by performing the above control, and accordingly, the yarn tension is set to an appropriate value. is held almost constant.

After the stretching device 1 has stopped once, by restarting it,
When low-speed operation begins, the thread tension begins to gradually increase due to drying and shrinkage of the thread structure. The thread tension at this time is
4, and is input by the tension detector 20 to the comparator 21 as an electrical tension signal. When the yarn tension becomes larger than the upper limit value, the comparator 21 generates a negative deviation output according to the state, and this deviation output operates the stretch setting device 17 to change the target stretch in the downward direction. Eventually, the yarn tension becomes smaller than the upper limit. Here, too, the tension control section 12 causes the stretch control section 11 to maintain the changed stretch as it is. After this, when the stretching device 1 enters high-speed operation, the yarn tension begins to gradually decrease. Finally, when the yarn tension becomes smaller than the lower limit value, the comparator 21 operates the stretch setter 17 with a positive deviation output to change the target stretch in the pulling direction. Eventually, the yarn tension recovers to become larger than the lower limit value and is maintained within the range between the upper limit value and the lower limit value.

Here, those upper and lower limit values are set in advance by the tension upper limit setter 2.
2. Manually set by the tension lower limit setter 23.

In this way, the tension control section 12 changes the target stretch of the stretch control section 11 while comparing the actual tension of the warp yarns 4 with the set upper and lower limit values of the tension, thereby changing the target stretch of the warp yarns 4. This will prevent abnormal increases or decreases in the tension value. Therefore, regardless of the operating state of the stretching device 1, the tension value of the warp yarns 4 is always within an appropriate tension range.

Embodiment 2 (FIGS. 4, 5, 6, and 7) In this embodiment, the stretch control section 11 executes stretch control during high-speed operation of the stretching device 1, and the tension is controlled only during low-speed operation. This is an example in which the control unit 12 is connected and the target stretch of the stretch control unit 11 is changed.

As shown in FIG. 4, the comparator 2 of the tension control section 12
1 is connected to the tension detector 20 at one input terminal, and set to the low speed tension setting device 25 at the other input terminal, and the deviation output of the comparator 21 is connected to the operating state detector 26.
The stretch setting device 17 is connected to the stretch setting device 17 via a contact point 26a.

FIG. 5 shows the operating state of the embodiment of FIG.

During high-speed operation, the stretch control section 11 performs the same control as in the first embodiment. When the stretching device l is in a low speed operation state, the operation state detector 26
detects this state and sets the contact 26a to the on state. At this time, the yarn tension begins to gradually increase due to drying and shrinkage of the yarn structure. The comparator 21 compares the actual tension of the warp threads 4 with the target tension value during low-speed operation, operates the stretch setting device 17 using the deviation output, and changes the target stretch to a lower value. For this reason, the stretch control unit 11 controls the stretch device 1 so that the tension becomes a lower stretch after the change, that is, an appropriate tension corresponding to low-speed operation.
will have to be adjusted.

Next, the embodiment shown in FIG. 6 is an example in which a tension memory 27 is interposed between the tension detector 20 and the comparator 21. The operating state detector 26 sets the contact 26b in an on state during high speed operation, but sets it in an off state when switching from this operating state to a stopped state or a low speed operation. At this moment of turning off, the tension memory device 27 stores the tension value during high-speed operation and prepares for the next operation.

As shown in FIG. 7, when the stretching device 1 is restarted and enters a low-speed operation state, the thread tension temporarily increases. During low speed operation, the comparator 21
The yarn tension at high speed in step 7 is taken as the target value, the actual yarn tension is taken in from the tension detector 20, and a signal corresponding to the deviation is sent to the stretch setting device 17. Therefore, the stretch setting device 17 can detect the amount of deviation. Change your stretch goals accordingly. In this way, during low-speed operation, although the stretch is temporarily reduced, the yarn tension is set to an appropriate value as in high-speed operation.

Example 3 (Figures 8 and 9) In this example, when the tension of the warp threads 4 is out of the upper and lower limits, the target stretch is changed and maintained at a predetermined tension value, and the target stretch is maintained at a predetermined tension value. This is an example in which stretch is also held at a predetermined value.

The tension control unit 12 includes a first comparator 28 connected to the tension upper limit setting device 22, a second comparator 29 connected to the tension lower limit setting device 23, and as an output control means for driving relays 35 and 36. , comparator 28.2
The polarity discriminator 31, 32 and flip-flop 33, 34 are connected to the terminal 9, respectively. These relays 35, 36 are connected to corresponding contacts 35a.
, 36a, the first comparator 28 or the second comparator 29 is selectively connected to the stretch setter 27. Note that the flip-flop 7 blocks 33 and 34 are reset by the comparator 30 connected to the output sides of the stretch initial setter 16 and the stretch setter 17.

That is, the relay 35 is set to the ON state when the thread tension becomes larger than the upper limit setting value, and is set to the OFF state when the stretch setting value becomes equal to the stretch initial setting value. Further, the relay 36 is set to the ON state when the tension becomes smaller than the lower limit setting value, and is set to the OFF state when the stretch setting value becomes equal to the stretch initial setting value.

FIG. 9 shows the operating situation of the above embodiment.

During high-speed operation, the stretch control unit 11 sets the tension of the warp yarns 4 to an appropriate value by maintaining the stretch at a target value. When the yarn tension becomes larger than the upper limit value during low-speed operation, a negative deviation output appears in the first comparator 21. This causes the polarity discriminator 31 to turn on the flip-flop 33 and turn on the relay 35.
is driven to turn on the contact 35a.

As a result, the deviation output of the first comparator 28 sets the stretch of the stretch setter 17 to be low. By adding this feedback, the speed at which the warp yarn 4 is sent out from the nip roll 5 increases, and the yarn tension tends to decrease, so that the yarn tension is held close to the upper limit setting value as a result. Thereafter, when high-speed operation starts, the yarn tension tends to decrease, so the target stretch is changed to a higher value so that the yarn tension is maintained at the upper limit setting value. Eventually, the stretch becomes equal to the stretch initialization value, so comparator 30 sets flip-flop 33 to the reset state at that point. As a result, the stretch control section 11 is not influenced by the feedback control from the tension control section 12, and independently performs stretch control with the target stretch. In addition,
When the thread tension becomes lower than the lower limit set value, the other second comparator 29-1 polarity discriminator 3
2 and the operation of the relay 36, the target stretch of the stretch control unit 11 is set higher than the initial setting value.

According to this embodiment, not only the tension but also the stretch of the warp yarns can be maintained at a predetermined value.

Other Examples In each of the above embodiments, the stretch control unit 11 has an actual stretch-〇 feedback loop as a minor loop, but this may be omitted. That is, based on the target stretch, the rotation direction and amount of rotation of the operating motor, which are set in advance in accordance with the target stretch, may be adjusted, and the stretch may be controlled in an open loop.

Effects of the Invention In the present invention, when the yarn tension changes during the stretch control process, the tension control section operates, and the target stretch is changed due to the deviation of the tension control system, thereby suppressing abnormal fluctuations in the yarn tension. It also prevents quality irregularities such as changes in yarn physical properties and destruction of the size film (it also prevents accidents such as yarn entanglement and yarn breakage).

[Brief Description of the Drawings] Fig. 1 is a block diagram of the basic configuration of the stretch control device of the present invention, Fig. 2 is a block diagram of the first embodiment, and Fig. 3 is a block diagram of the basic configuration of the stretch control device of the present invention.
4 is a block diagram of the second embodiment. FIG. 5 is an explanatory diagram of the operation of the stretch control device of FIG. 4. FIG. 6 is a diagram of another example of the second embodiment. Block diagram, 7th
The figures are an explanatory diagram of the operation of the stretch control device shown in FIG. 6, FIG. 8 is a block diagram of the stretch control device of the third embodiment, and FIG.
This figure is an explanatory diagram of the operation of the stretch control device shown in FIG. 8. ■... Stretching device, 2... Drive motor, 3... Continuously variable transmission, 4... Warp thread, 5.6... Nip roll, 10
... Stretch control device, 11... Stretch control section,
12...Tension control unit, 13, I4...Rotation detector, 20
...Tension detector, 21..Comparator, 22..Tension upper limit setting device, 23..Tension lower limit setting device, 25..Low speed tension setting device, 27..Tension memory device, 28..First comparator , 29... second comparator, 35.36...
·relay. Patent applicant Tsudakoma Kogyo Co., Ltd. Agent
Person Patent Attorney Kuni Nakagawa Figure Figure Time - Figure Figure Figure 5 Figure Time → Figure Figure Time

Claims (5)

[Claims] (1) In a stretching device in which the rotation of the drive motor is speed-changed by a continuously variable transmission and a target circumferential speed ratio is provided between the nip roll on the upstream side and the nip roll on the downstream side in the running direction of the warp yarns, the above-mentioned A stretch control unit that operates the operation unit of the continuously variable transmission detects the yarn tension between the upstream nip roll and the downstream nip roll, and controls the stretching according to the deviation between the detected yarn tension and the target tension. A stretch control device comprising a tension control section that changes a target stretch of the control section. (2) The tension control section includes a tension detector that detects yarn tension between the upstream nip roll and the downstream nip roll;
Consists of a setting device that sets the upper and lower limits of the target tension, and a comparator that compares the detected thread tension with the upper and lower limits of the target tension and changes the target stretch of the stretch control unit based on the deviation. The stretch control device according to claim 1, characterized in that: (3) The tension control section includes a tension detector that detects yarn tension between the upstream nip roll and the downstream nip roll;
A setting device that sets the target tension during low-speed operation, a comparator that compares the detected yarn tension with the target tension during low-speed operation to determine the deviation, and sends the deviation output of the above comparator to the stretch control section during low-speed operation. 2. The stretch control device according to claim 1, further comprising a driving state detector. (4) The tension control section includes a tension detector that detects yarn tension between the upstream nip roll and the downstream nip roll;
A tension memory device stores the yarn tension during high-speed operation, a comparator generates a deviation output by comparing the detected yarn tension with the yarn tension from the tension memory device, and a comparator outputs the deviation output from the comparator during low-speed operation. 2. The stretch control device according to claim 1, further comprising an operating state detector sent to the stretch control section. (5) The tension control section includes a tension detector that detects yarn tension between the upstream nip roll and the downstream nip roll;
A tension upper limit setting device sets the upper limit of the target tension, a tension lower limit setting device sets the lower limit of the target tension, and the detected thread tension is compared with the upper limit of the target tension to calculate the deviation output. A first comparator that generates the yarn tension, a second comparator that compares the detected yarn tension with the lower limit of the target tension and generates a deviation output thereof, and a second comparator that compares the output of the first and second comparators with the lower limit of the yarn tension. an output control means for selectively outputting the output to the stretch control section according to the direction of variation;
2. The stretch control device according to claim 1, further comprising a comparator that disconnects the second comparator from the stretch control section.