JP2877521B2 - Method and apparatus for controlling warp tension of loom - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a loom for minimizing the generation of a weaving step due to the elongation of a warp during stoppage.
The present invention relates to a warp tension control method for a loom and an apparatus therefor.

[0002]

2. Description of the Related Art When a loom is stopped for a long time, a warp is stretched and a weaving front moves, so that a weaving step called a stop step may occur.

In order to solve this problem, it has been considered effective to reduce the warp tension during stoppage and minimize the elongation of the warp during stoppage (for example, Japanese Patent Application Laid-Open No. Sho 54-1066).
No. 61). When the loom is stopped, the warp tension is extremely reduced or the warp is completely loosened, regardless of the warp tension during weaving. Is returned to a steady state value. In addition, at this time, during the operation of the loom, the actual value of the warp tension is read and stored in accordance with the crank angle of the loom. It has also been proposed to accurately reproduce the warp tension corresponding to the crank angle (Japanese Unexamined Patent Publication No.
1-296146).

[0004]

According to the prior art, when the loom stops, the warp tension is set extremely low, so that the elongation of the warp during stoppage can be kept small. However, on the other hand, by loosening the warp,
Since the cloth fell moves greatly, it is difficult to accurately return the cloth fell to its original position even if the warp tension is restored during start-up. The problem of becoming inevitable. That is, since each warp is inserted into the heald mail and is in contact with various rolls including the tension roll, the warp once loosened, even if the predetermined warp tension is reproduced, is in contact with the heald mail or the roll. Is changed, and accurate return of the cloth fell position cannot be performed.

[0005] In addition, storing the warp tension corresponding to the crank angle during weaving is not practical because the configuration of the control device becomes complicated.

Accordingly, an object of the present invention is to store the warp tension at the time of stopping the loom and control the warp tension at the time of stopping the loom using this as a target value in view of the situation of the prior art. A method for controlling the warp tension of the loom, which minimizes the occurrence, and also suffices for the entire apparatus to have a very simple configuration;
It is to provide the device.

[0007]

According to a first aspect of the present invention for achieving the above object, when a loom provided with an electric warp tension control system is stopped, when the loom is completely stopped. The gist is to store the warp tension and to operate the warp tension control system with the stored warp tension as a target value while the loom is stopped to maintain the warp tension.

[0008] The construction of the second invention comprises a memory for storing the warp tension when the loom is completely stopped, and a memory for storing the warp tension when the loom is stopped.
The gist is to provide a warp tension control system for controlling the warp tension while using the set tension set in the setting device as a target value during operation of the loom during the operation of the loom.

The storage device may store the warp tension a predetermined time after the stop signal or the stop completion signal of the loom is generated.

[0010]

According to the first aspect of the invention, the warp tension during the stoppage of the loom is maintained at the value when the loom is completely stopped. Therefore, it is inevitable that the warp will undergo some stretching while the loom is stopped,
This elongation is absorbed, for example, by rotating the warp beam driven by the warp tension control system in the reverse direction. At this time, the contact state between the cloth fell position, the warp, the heald mail and various rolls, And the like can be kept almost unchanged, and the risk of weaving steps can be greatly reduced as compared with the case where the warp is once loosened.

[0011] The time when the loom is completely stopped may be the time when the mechanical vibration of the tension roll, the warp and the like converges after the loom is stopped and the warp tension shows a constant value. In addition, when an automatic reverse spinning operation or the like is performed after the loom is stopped in order to discharge a defective weft, it refers to a state in which the warp tension has stopped at a constant value after the completion of those additional operations. And

According to the configuration of the second invention, the memory stores the warp tension when the loom is completely stopped, and the warp tension control system operates the warp tension stored in the memory while the loom is stopped. Therefore, the first invention can be well implemented.

Further, if the storage device stores the warp tension a predetermined time after the stop signal or the stop completion signal of the loom is generated, the predetermined time is adjusted so that the target can be adjusted during the stop of the loom. As the warp tension used as the value, the optimum value at any time after the loom is stopped can be stored.

[0014]

Embodiments will be described below with reference to the drawings.

The warp tension control device of the loom comprises a tension detector LD for detecting the warp tension T, a device main body 10, and a delivery motor M to be operated by the device main body 10.

The loom includes an arbitrary type of weft insertion mechanism (not shown), heald frames HF, HF, reed R, warp beams B1,
And a woven fabric beam B2. When the warp P is unwound from the warp beam B1, the tension roller TR,
After passing through the heald frames HF, HF and the reed R, it reaches the cloth fell Wa. The warp yarns P, P are formed by heddle frames HF, HF.
a is formed. Between the reed R and the weave Wa, a weft (not shown) inserted into the warp opening Pa is driven into the weave Wa via the reed R, and the woven fabric W can be woven. The woven fabric W includes a guide roll GR1, a pressure roll PR, a winding roll KR having PR, and a guide roll G.
After passing through R2, it is wound on a woven fabric beam B2.

The tension detector LD is a load cell for detecting the warp tension T applied to the tension roll TR by the warp P, P.
When compressing 1, the tension detector LD can convert the warp tension T into an electrical output signal S 1 and output it.

The warp tension T from the tension detector LD is input to the apparatus main body 10. The warp tension T is input to an averaging circuit 11 and also to an addition point 12 and a memory 21 via a switch 11a. The output of the averaging circuit 11 is connected to a switch 11a. Also,
The switch 11a receives a switch signal S from a control circuit (not shown).
2a has been entered.

The storage device 21 forms a setting circuit 20 together with the setting device 22 and the switching device 23. An operation command signal S3 from a control circuit (not shown) is input to the storage device 21. The output of the operation command signal S3 is sent to the addition point 12 via a switch 23.
It is connected to the. The output of the setting device 22 is also connected to the switching device 23, and the switching signal S2b is input to the switching device 23.

The output of the addition point 12 is supplied to the control amplifier 13
Is connected to the delivery motor M via The delivery motor M is connected to the warp beam B1 via a gear mechanism G. The woven fabric beam B2 is to take up the woven fabric W by a winding motor (not shown).

During the normal operation of the loom, the switch 11
The input sides of a and 23 are switched to the averaging circuit 11 side and the setting unit 22 side, respectively. That is, when the warp tension T from the tension detector LD is input to the averaging circuit 11, the warp tension T is averaged with respect to time, and as an average warp tension Ta,
It is input to the addition point 12. On the other hand, from the setting circuit 20, the set tension Tos set in the setting device 22 is input to the addition point 12, so that the addition point 12 obtains a tension deviation ΔT = Tos−Ta at its output side. Can be. The tension deviation ΔT is transmitted through the control amplifier 13 to the motor M
Output motor M, the tension deviation Δ
The warp beam B1 can be driven to rotate so as to eliminate T. That is, the tension detector LD, the averaging circuit 1
1, addition point 12, control amplifier 13, delivery motor M
Form an electric warp tension control system for controlling the warp tension T such that the average warp tension Ta matches the set tension Tos.

Generally, the warp tension T is determined by the heald frames HF, HF
Vibrating greatly every one rotation of the crank angle θ of the loom (FIG. 2), and the average value is the average warp tension Ta. Therefore, the warp tension control system at this time operates with the set tension Tos as the target value.

When the cause of the stoppage occurs in the loom, a stop signal is output from a detection device (not shown), for example, a weft feeler, a warp break detection dropper, or the like, and the loom stops after the coasting operation of about one rotation. On the other hand, when the stop signal is output,
The warp tension control system uses, for example, means for forcibly holding the input side of the control amplifier 13 at a zero level.
The operation is stopped once.

Thereafter, when the loom is completely stopped, switching signals S2a and S2b and an operation command signal S3 are output from a control circuit (not shown). Therefore, the switches 11a, 23
In response to this, the respective input sides are switched to the tension detector LD side and the storage unit 21 side, and at the same time, the storage unit 21 detects the warp tension T at that time supplied via the switching unit 11a. , Memory tension Tom. Subsequently, when the operation of the warp tension control system is restored, the memory tension Tom supplied through the switch 23 and the warp tension T supplied through the switch 11a are added to the addition point 12 at this time. After that, the warp tension control system can control the delivery motor M so that the warp tension T matches the stored tension Tom. Accordingly, the warp tension T during the stoppage of the loom can accurately maintain the memory tension Tom, that is, the warp tension T when the loom is completely stopped, and the warp tension control system at this time uses the memory tension Tom.
om is operating with the target value.

When the cause of the stop of the loom is eliminated and the loom is restarted, a start signal is output from a control circuit (not shown), and the loom is started. Thereby, the switching signals S2a, S2b
Are lost, the switches 11a and 23 have their input sides switched to the averaging circuit 11 side and the setter 22 side, respectively.
Therefore, the warp tension control system can return to the original operating state during normal operation. Note that the warp tension control system at this time returns to the operating state during normal operation when a command such as a jogging operation is given to the loom by the weaver in order to eliminate the cause of stopping the loom. It may be.

In general, after the loom is completely stopped, the warp tension T is determined by the elapse of the elapsed time t due to the elongation of the warp P.
Decrease almost exponentially (FIG. 3). Therefore,
When the warp tension T is stored in the storage unit 21 as the storage tension Tom by the operation command signal S3, the value of the storage tension Tom fluctuates greatly due to the delay time ta from when the loom stops until the operation command signal S3 is generated. there is a possibility. However, according to experiments, if ta ≤ 1 (minute),
It is known that a weaving step hardly occurs in the woven fabric W after the restart. That is, if ta ≤ 1 (minute), the warp yarns P, P elongate in the meantime are small, and therefore, the position of the weave Wa, the heald of the warp yarns P, P and the tension roll TR and the heald frames HF, HF. Contact status with email,
There is almost no change in the state of contact between the woven fabric W and the guide roll GR1. Further, the subsequent elongation of the warp yarns P, P is achieved by driving the warp beam B1 in the reverse direction to change the warp tension T to the memory tension Tom.
It is presumed that, by maintaining the ratio, the generation of the weaving step can be effectively prevented. In other words, by maintaining the warp tension T during the stoppage of the loom at the value immediately after the loom is completely stopped, the warp yarns P, P
Can maintain the mechanical state constant before and after the loom is stopped, which is considered to have greatly contributed to prevention of the weaving step.

In the above description, the switching signals S2a, S2
b, When the operation command signal S3 is generated and the warp tension control system is operated with the memory tension Tom as a target value, generally,
The loom stops completely and the tension roll TR, warp P,
It is sufficient when the mechanical vibration of P converges and the warp tension T shows a constant value. Therefore, when the loom performs an automatic reverse spinning operation after the stop by the stop signal, the warp tension control system is preferably operated after these operations are completed. The same applies to the case where the automatic warp closing operation is performed after the loom is stopped in order to avoid applying an excessive warp tension T to the warp yarns P while the loom is stopped. When the automatic warp closing operation is performed, the small warp tension T after closing can be stored as the storage tension Tom.

Switching signals S2a, S2b, operation command signal S3
Is, for example, a setting device 31 for setting the delay time ta;
It can be generated by a combination with the timer 32 (FIG. 4). The timer 32 can output the switching signal S2a and the like after the delay time ta when the operation signal S4 composed of either the stop signal of the loom or the stop completion signal is input. Here, the stop completion signal is a signal indicating that the above-described automatic reverse spinning operation and the automatic warp closing operation have been completed after the loom is stopped.

The control amplifier 13, which forms a part of the warp tension control system, controls the control constant between the normal operation using the averaging circuit 11 and the stoppage of the loom not using the averaging circuit. May be switched so as to be optimal. Furthermore, when starting the loom, in order to avoid a starting stage due to a shortage of the initial beating force, when performing a so-called reverse idling start, the control amplifier 13 is used or directly without using it. The motor M may be controlled to perform a so-called kickback operation.

The operation target of the warp tension control system during normal operation or stoppage of the loom may be a winding motor (not shown) instead of the delivery motor M.

[0031]

As described above, according to the first aspect of the present invention, the warp tension when the loom is completely stopped is stored, and the stored warp tension is set as the target value while the loom is stopped. By operating the tension control system, even if elongation occurs in the warp during stoppage, this elongation can be absorbed as it is by the warp tension control system, so that the cloth fell position, the warp and tension roll, the heald mail Can keep the contact state unchanged, thus minimizing the generation of weaving steps including stop and start steps, and memorizing warp tension corresponding to the crank angle and reproducing this Therefore, there is an excellent effect that the control device can be realized with a very simple configuration.

According to the second aspect of the present invention, there is an effect that the first aspect of the present invention can be smoothly implemented by combining the storage device and the warp tension control system.

[Brief description of the drawings]

FIG. 1 is a block diagram of the overall configuration

FIG. 2 is an operation explanatory diagram.

FIG. 3 is a characteristic diagram of warp tension

FIG. 4 is a block diagram of a main part of another embodiment.

[Explanation of symbols]

 T: Warp tension Tos: Set tension Tom: Memory tension 21: Memory device 22: Setting device

Claims (3)

(57) [Claims] When a loom having an electric warp tension control system is stopped, a warp tension when the loom is completely stopped is stored. During the stop of the loom, the stored warp tension is set as a target value to control the warp tension. A warp tension control method for a loom, characterized in that a warp tension is maintained by operating a system. 2. A storage device for storing a warp tension when the loom is completely stopped, and a target value based on the warp tension stored in the storage device when the loom is stopped. And a warp tension control system for controlling the warp tension with the set tension set as a target value. 3. The warp tension control device for a loom according to claim 2, wherein the storage unit stores the warp tension after a predetermined time after a stop signal or a stop completion signal of the loom is generated.