JPH024134Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for detecting warp tension fluctuations in a loom.

Regardless of whether the feeding system is mechanical or electric, means are taken to balance the warp tension applied to the tension rolls, the elasticity due to the amount of deflection of the spring, and the gravity of the weight. In this case, the tension is detected indirectly by detecting the amount of displacement of the tension roll, that is, by detecting the position.

This conventional detection means has the following problems. First of all, since the tension is set using a displacement amount that is different in dimension from the tension, it is actually difficult to set the tension arbitrarily. Second, the degree of dependence on the tension spring, whose elastic properties are difficult to fix, is large, resulting in large variations in detection accuracy between individual looms. Third
In addition, it is inevitable to use a link mechanism to support the tension roll, making the device complex and having many swinging parts, which poses a safety problem.

Therefore, the purpose of the present invention is to eliminate the drawbacks of the above-mentioned conventional examples, and to provide an effective means that is not affected by the characteristics of the tension spring and can directly detect fluctuations in warp tension. .

Based on the above object, the present invention supports the tension roll with a tension spring, and also interposes a pressure sensor between the tension spring and a support at a fixed position, and uses this pressure sensor to measure the warp thread tension. It is designed to directly detect fluctuations in

EMBODIMENT OF THE INVENTION Hereinafter, the structure of this invention will be concretely demonstrated based on the Example shown in the figure.

First, FIG. 1 shows the configuration of a warp tension detection device 1 of the present invention in relation to warp delivery and winding of a loom. The warp yarns 2 are wound around a delivery beam 3, and after being wound around a tension roll 4, an opening 6 is formed by the vertical movement of the heald 5, and the warp yarns 2 intersect with the weft yarns 7 at the position of the opening 6. The cloth 8 is wound up onto a winding beam 12 via a guide roll 9, a winding roll 10, and a guide roll 11.

The warp tension detecting device 1 of the present invention movably supports the tension roll 4, and has a tension sensor between the shaft 13 of the tension roll 4 and a support 14 located at a position such as a frame of a loom. Spring 15 and pressure detector 1 such as a load cell
6 are interposed in series. Shaft 13, tension spring 15 and pressure detector 16
are arranged on a straight line, and correspondingly, the displacement direction of the tension roll 4 is set on the same straight line.

The sending beam 3 is actively driven by a drive motor 17 and a speed reducer 18.

Next, FIG. 2 shows a control device 19 for automatically controlling the rotational speed of the drive motor 17 based on the detection signal of the pressure detector 16. As shown in FIG. The pressure detector 16 includes an amplifier 20, an A/D converter 21,
It is connected to one input end of a comparator 24 via a latch 22 and a winding diameter corrector 23. Further, a tension setting device 25 is connected to the other input terminal of the comparator 24. The output terminal of this comparator 24 is a D/A
It is sequentially connected to the drive motor 17 via a converter 26, a summing point 27 and a drive amplifier 28. Further, the winding diameter detector 29 is connected to the winding diameter corrector 23, and is branched off and connected to the addition point 27 via the D/A detector 30. Also, the drive motor 17
A rotation speed detector 31 is connected to the rotation speed detector 31, and its output terminal is connected to the addition point 27. moreover,
An angle signal generator 32 is connected to the latch 22. This angle signal generator 32 updates the contents of the latch 22 at every fixed angle of the loom and stores a signal corresponding to the tension of the warp threads 2 at the time of the update. Next, the operation of the warp tension detection device 1 and the operation of the control device 19 in relation to this will be explained.

The winding diameter detector 29 detects the winding diameter of the warp yarn 2 on the sending beam 3 by electrical or mechanical means, and detects the basic speed corresponding to this winding diameter via the D/A converter 30 and the summing point 27. , to the drive amplifier 28. Therefore, the drive amplifier 28 drives the drive motor 17 at a rotational speed corresponding to the basic speed. The rotational speed of the drive motor 17 is detected by the rotational speed detector 31 and is negatively fed back to the addition point 27 . This causes the drive motor 17
is controlled under feedback control. In this way, the delivery beam 3 receives the rotational force of the drive motor 17 and automatically sends out the warp threads 2 as weaving progresses.

Even if the weaving speed is constant, the tension of the warp yarns 2 will fluctuate due to factors such as the accuracy of the feed-out control and the elongation of the warp yarns 2. Due to this variation in tension, the tension roll 4 detects a change in the tension of the warp threads 2 by changing its position. When the position of the tension roll 4 changes, the tension spring 15 moves the shaft 13 and the support 14 in proportion to the amount of displacement of the tension roll 4.
proportionally increase or decrease the elasticity between
Therefore, the pressure detector 16 converts the change in elasticity into an electrical analog signal, passes through an amplifier 20, and sends it as a digital signal to a latch 22 by an A/D converter 21, where it is temporarily held. let The angle signal generator 32 causes the latch 22 to perform an updating operation at every fixed angle of the loom, and sequentially updates the stored contents. In this way, latch 2
2 stores information on the tension of the warp threads 2 at each fixed angle of the loom. This latch 22 information is corrected by the coefficients of a winding diameter corrector 23 and then sent to one input of a comparator 24.
The winding diameter corrector 23 takes into account that the winding angle of the warp threads 2 with respect to the tension roll 4 changes due to a change in the winding diameter of the warp threads 2 on the sending beam 3, and It is provided to correct the component force of the tension roll 4 using a coefficient. Therefore, a guide roll 33 is provided between the delivery beam 3 and the tension roll 4, and when the guide roll 33 always maintains the winding angle of the warp 2 with respect to the tension roll 4, The winding diameter corrector 23 may be omitted. Of course, in this case, the winding diameter detector 29 and the D/A detector 30 can also be omitted.

Now, the comparator 24 compares the set tension value from the tension setting device 25 and the actual tension value detected by the pressure detector 16, and outputs an output signal according to the difference between these values, that is, the deviation. occurs and this is D/A
It is converted into an analog quantity by a converter 26 and applied to an addition point 27 as a plus or minus signal.

Incidentally, the tension of the warp threads 2 acts on the tension roll 4 as a resultant force at the position where the warp threads 2 are wound, but this resultant force acts as a compressive force on the tension spring 15 and is directly transmitted to the pressure detector 16. communicated. Therefore, the pressure detector 16 directly detects the tension of the warp threads 2.

If the elastic modulus of the tension spring 15 differs from product to product, the amount of compression of the tension spring 15 will differ for the same tension value of the warp threads 2. However, pressure detector 1
The force acting on the warp yarns 6 always corresponds to the tension of the warp yarns 2, regardless of the difference in the amount of compression of the tension springs 15. Therefore, even if there are variations in the characteristics of the tension springs 15, the tension of the warp yarns 2 can be accurately detected.

In addition, in a loom, the tension of the warp threads 2 changes in a pulsating manner due to shedding motion, beating motion, etc. during one revolution of the loom. Moreover, this change in tension during one rotation is not normally subject to tension control. Therefore, when detecting the tension of the warp threads 2, the tension of the warp threads 2 is detected at a constant rotation angle during one rotation of the loom, and this is used as a representative value of the warp thread tension, or Find the average value of the tension of the warp threads 2 at regular intervals in synchronization with the rotation, and use that as the representative value of the tension of the warp threads 2, or the maximum or minimum value of the tension of the warp threads 2 during one rotation of the loom. It is necessary to take into consideration such things as making the value a representative value for the warp yarn 2.

By the way, in the above embodiment, the pressure detector 16 is fixed to the support body 14 side, but this pressure detector 16 may be interposed between the shaft 13 and the tension spring 15, or the pressure detector 16 may be interposed between the shaft 13 and the tension spring 15. As shown in Figure 3, the tension spring 15 is divided into two parts,
It may be interposed between the two.

Furthermore, in any of the above embodiments, the tension roll 4 is directly attached to the tension spring 15.
However, in FIG. 4, a swingable lever 34 is used to support the tension spring 15 and the pressure sensor 16 between one end of the lever 34 and the support body 14. It is intervening.
Although similar effects can be obtained in this embodiment, the safety of the device is compromised due to the rocking motion of the lever 34.

In this invention, since the pressure detector is interposed in series with the tension spring between the tension roll and the fixed support, the tension of the warp threads can be directly detected regardless of the elastic properties of the spring.
Also, since tension is detected as an electrical signal,
The tension can be set depending on the magnitude of the electrical signal, and therefore accurate tension setting is possible. In addition, in an embodiment in which the tension roll is directly supported in the displacement direction by a spring, there is no swinging member such as a lever, or the mechanism is simplified.
Improves safety.

[Brief explanation of the drawing]

Fig. 1 is a schematic side view of the warp tension detection device of the loom, Fig. 2 is a block diagram of the control device, and Fig. 3 is a schematic side view of the warp tension detection device of the loom.
FIG. 4 is a schematic side view of another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Warp tension detection device of a loom, 2... Warp thread, 3... Delivery beam, 4... Tension roll, 14... Support body, 15... Tension spring, 16... Pressure detector, 19... …Control device.

Claims (1)

[Scope of utility model registration request] A warp tension detection device for a loom, characterized in that a tension spring and a pressure detector are interposed in series between a tension roll supported movably in contact with the warp and a support at a fixed position. Device.