JP2756722B2 - Warp thread compensation method - Google Patents

Description

Description: TECHNICAL FIELD [0001] The present invention relates to a tension correction method for a tension control system for electric feeding of a loom.

[Conventional technology]

Japanese Patent Laying-Open No. 59-194963 discloses a tension correcting means. The tension correcting means calculates the detected tension value with the change in the winding diameter while calculating the input angle of the strip to the tension roll based on the winding diameter in accordance with the change in the contact angle of the strip to the tension roll. Has been corrected.

[Problems of the prior art]

According to the above-described technology, when the band material is a warp yarn, by changing the type of the fabric, when the tension roll and its position are changed, the number of setting values to be changed accordingly increases, and the initial work is complicated. In addition, since the calculation is complicated, there is a problem that the control system is complicated.

[Object of the invention]

Accordingly, it is an object of the present invention to reduce the number of parameters at the time of correction in detecting the tension of electric feeding, and to simplify the correction calculation and control system.

[Solution Means and Action of the Invention]

To this end, the present invention provides an electric feeding tension control system for a loom, which detects the tension of a warp yarn as a resultant force in the warp winding direction at the position of a tension roll, and when the sending beam has a maximum winding diameter, By setting the warp yarn tension to the target tension and setting the detected tension value at this time as the target value of the tension control system, the correction amount at the maximum winding diameter is set to “1”,
As the winding diameter decreases, a correction amount that changes at a fixed ratio is multiplied by a detected tension value or a control target value and sent to a comparator of a control system.

As described above, since the correction is performed using the correction amount that changes based on the correction coefficient, only one parameter needs to be changed with the change of the fabric structure, and the initial setting is easy. When the correction coefficient is set, only the winding diameter is required for the calculation of the correction, so that the calculation of the correction can be simplified, and the control system for the correction can be constituted by simple electric elements. Since the detected tension is corrected by linear approximation, an error always occurs between the actual tension value of the warp and the corrected detected tension value, but if the correction coefficient is an appropriate value, the error amount is In the range of practical control, there is no adverse effect.

The first embodiment below is an example of correcting the detected tension value.
The second embodiment is an example in which a control target value is corrected.

Embodiment 1 (FIGS. 1 and 2) FIG. 1 shows a tension control system for electric delivery.

The warp yarn 1 is wound around the delivery beam 2, forms a sheet, is wound around the tension roll 3 at a predetermined winding angle θ, forms an opening together with the heald 4, intersects with the weft yarn 5, and crosses the cloth 6. Becomes Then, the cloth 6 is wound up around the outer periphery of the cloth winding beam 8 via the winding roll 7. Here, the sending beam 2 is
The delivery mode 14 and the reduction gear 15 are configured to be rotationally driven in the delivery direction. The delivery motor 14 is controlled by the tension control device 10. The tension control device 10 adjusts the rotation of the delivery motor 14 in the delivery direction so that the warp yarn tension T1 becomes the target tension value t0 during weaving.

In the process of sending out warp yarn 1, warp yarn tension T1 of warp yarn 1
Is detected as a signal of the detected tension value T2 by the load cell 9a and the tension detector 9 at the position of the tension roll 3, and is directly displayed on the display 11 as necessary. Here, the load cell 9a and the tension spring 12 are oriented in the direction of the resultant force of the warp yarn 1 between the tension roll 3 and the loom frame 13 in a serial state.

In the sending process, the winding diameter (diameter) D of the warp yarn 1 in the sending beam 2 changes in the decreasing direction from the maximum winding diameter Dmax to the minimum winding diameter Dmin, and the winding angle θ also changes. The relationship between T2 and the actual warp yarn tension T1 is not constant.

Therefore, this embodiment introduces a correction coefficient a, a winding diameter (diameter) D, and the like in order to correct the detected tension value T2, and
Kd is obtained by the following correction formula.

First, the following work is performed in the trial weaving stage. When the winding diameter D is the maximum, the warp thread tension T1 is set to the target tension value t0, and the detected tension value T2 at that time is set as the control target value t0, and set by the target setter. Thereby, the correction amount Kd at the time of the maximum winding diameter Dmax is set to “1”. Next, the correction coefficient a in the above equation is set to an appropriate value, for example, “5
Set to "0", weaving is actually continued, and assuming the graph of FIG. 2, it is checked whether the warp yarn 1 becomes slack or over tension occurs as the winding diameter D decreases. If the warp yarn 1 becomes slack or over-tension occurs, the correction coefficient (the slope of the straight line) a is corrected in a direction to eliminate the tension, and finally the optimum correction coefficient a is determined. That is, if the detected tension is corrected based on the determined correction coefficient a, it can be said that there is no adverse effect on the control in the entire winding diameter changing process. Then, this is set as a correction coefficient at the time of normal weaving by the coefficient setting unit 16 and is used as one input of the tension corrector 17. The winding diameter D is obtained indirectly from the ratio between the rotation amount of the delivery beam 2 and the rotation amount of the main shaft 20 driven by the driving motor 22. In the case of this embodiment, the rotation amount of the delivery beam 2 is obtained from the number of pulses of the pulse generator 21 connected to the delivery motor 14, and the rotation amount of the main shaft 20 is determined by the number of pulses of the encoder 23 connected thereto. And is calculated by the winding diameter detector 24. Here, the tension corrector 17
The detected tension value T2, the correction coefficient a, and the current winding diameter D are input, and a correction amount Kd is obtained from the above correction formula.
To calculate the corrected tension Kd · T2 and send it to the comparator 18 as a negative signal, that is, as a tension feedback signal. Therefore, the output of the comparator 18 becomes (t0−Kd · T2), and becomes the next input of the tension controller 19 as a deviation.

Here, the tension controller 19 receives the output of the comparator 18, that is, the deviation, as an input, adds an output proportional to the deviation, sends the output to the drive amplifier 26 via a matching point 25, and eliminates the deviation of the delivery motor 14 at a predetermined speed. In the direction by a predetermined amount.
The output of the pulse generator 21 is output from the F / V converter 2
The number of pulses is converted to a voltage by 7 and added at point 2
By negative feedback to 5, it is also used as a speed feedback signal.

[Embodiment 2 (FIGS. 3 and 4)] In this embodiment, as shown in FIG. 3, a tension detector 9 is directly connected to a comparator 18 in order to correct a control target value t0. A target corrector 29 is interposed between the target setter 28 and the comparator 18, and the function of the coefficient setter 16 is also performed by the target setter 28.

The correction amount Kd in this embodiment is represented by the following correction formula.

Here, since the correction amount Kd decreases as the winding diameter D increases, it is represented as a straight line graph in FIG. Also in this embodiment, the correction coefficient a is determined by experimentally finding the optimum value by trial weaving as described above. Therefore, the output of the comparator 18 is (Kd · t0−T2).

〔The invention's effect〕

In the present invention, the only parameter to be changed in accordance with the change of the fabric structure is the correction coefficient of the correction amount, so that the initial setting is easy and the configuration of the control system can be simplified.

In particular, during weaving, the winding diameter of the warp sending beam is detected, a correction amount is detected based on the detected winding diameter, and the correction amount is multiplied by one of the detected tension value and the control target value. By adjusting the tension, a signal to be sent to the comparator of the tension control system is created, so that the resultant force in the warp winding direction can be accurately detected at the tension roll position regardless of the change in the winding diameter of the sending beam.

[Brief description of the drawings]

FIG. 1 is a block diagram of a feed warp tension control system according to a first embodiment, FIG. 2 is a graph of a correction amount with respect to a winding diameter,
FIG. 3 is a block diagram of a main part of the second embodiment, and FIG. 4 is a graph of a correction amount with respect to a winding diameter. 1 ... warp yarn, 2 ... delivery beam, 3 ... tension roll, 10 ... tension control device, 14 ... delivery motor, 16 ... coefficient setting device, 17 ... tension corrector, 18 ... comparator, 19 ... tension controller, 24 ... winding diameter detector, 28 ... target setting device.

Claims (1)

(57) [Claims] 1. During weaving, a warp yarn tension is detected as a resultant force of a warp yarn in a direction of winding a warp yarn on a tension roll at a position of a tension roll, and the detected warp yarn tension is detected as the winding diameter of a warp yarn delivery beam decreases. In the tension control system of the electric feeder of the loom, the warp yarn tension is set to the target tension at the maximum winding diameter of the feed beam, and the detected warp yarn tension value detected at this time is set as the control target value. , The correction amount at the maximum winding diameter is set to “1”, and the correction amount that changes at a fixed ratio with the decrease in the winding diameter of the sending beam is calculated based on the winding diameter of the sending beam at that time. Multiplying the calculated correction amount by one of the detected tension value and the control target value, and then feeding the multiplied correction value to a comparator of a tension control system. Force correction method.