JPH0213055B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a tension control method for warp threads in a loom, particularly a tension control method suitable for controlling the feed rate of loom pile warp threads or ground warp threads for towels. It is related to.

[Conventional technology and its problems]

Generally, a loom is equipped with a tension detection means during the movement of warp threads. When the loom rotates and winding begins and the warp threads become tensioned, the tension detection means moves forward, and this movement detection signal drives a motor to feed the warp threads. The roll is rotated by the amount of movement, advancing the warp threads forward, and by repeating this, the warp threads are fed while keeping the thread tension constant.

By the way, when a pile is formed using warp yarns as in a towel loom, as shown in FIG.
The feed amount is small in the weft C ₁ and second weft C ₂ parts,
Since the pile D is formed by increasing the feed amount of the third weft C ₃ , a large tension is applied to the pile warp A when the third weft C ₃ is driven.

However, in the conventional warp sending-out method, the warp threads are rotated each time by the amount of movement, so the tension adjustment of the warp threads becomes intermittent.

For this reason, in towel looms in which the feed amount of the pile warp yarns is not constant, there is a problem in that the pile warp cannot be fed sufficiently during pile formation, resulting in uneven pile height.

This invention was made to solve the above-mentioned problems, and is a warp tension control system for a loom that can average and keep the pile warp feeding amount constant and form piles of uniform height. The purpose is to provide a method.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention provides a loom in which a warp delivery roll is driven by a motor, in which the motor is repeatedly energized in predetermined cycles, and
The warp tension fluctuation is detected by a tension roll and a switch, and the switch changes the off timing within the divided cycle number according to the warp tension fluctuation, and the motor is turned on and off to increase speed or The tension of the warp threads is controlled by slowing down the threads.

[Effect]

A tension roll moves to follow changes in the warp tension, and the tension changes in the warp are electrically detected by the tension roll and the switch.

The motor that drives the warp delivery roll is constantly driven by repeating it in a predetermined number of cycles, and the switch that detects the warp drive fluctuation detects the tension within the divided number of cycles. The power to the motor is turned off at a time corresponding to the state.

Therefore, the motor is essentially driven by repeatedly turning on and off, and when the number of energization cycles is large, the speed of the warp delivery roll is increased, and when the number of cycles is small, it is decelerated to follow the warp tension fluctuations. This means that the warp thread feed amount is averaged and kept constant.

〔Example〕

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

FIG. 1 is an explanatory diagram of the towel loom and the warp tension control mechanism, and the pile warp A drawn out from roll 1 and the ground warp B drawn out from roll 2 are
They each pass through a reed 5 via tension rolls 3 and 4 and are wound up on a winding roll 6.

Motor M that drives roll 1 of pile warp A
is driven by a commercial AC power source via an operation switch 7, a control box 8, and a motor drive circuit 9 to rotate the roll 1 in the direction in which the pile warp yarns A are sent out.

A tension detection mechanism 10 including a tension roll 3 is provided during the movement of the pile warp yarns A, and is designed to electrically detect changes in tension of the pile warp yarns A.

2 and 3 illustrate the specific structure of the tension detection mechanism 10, in which a tension dot 11 is provided on the tension roll 3 which can freely swing, and the tension dot 11 is provided at the front and rear positions in the swing direction. , an acceleration proximity switch _S1 and a deceleration proximity switch _S2 are arranged.

When the tension of the pile warp A being sent out from the roll 1 becomes tense, the dot 11 moves to the acceleration proximity switch _S1 , and this switch _S1 moves the pile warp A
Detect tension. Further, when the pile warp yarns A become loose, the dock 11 moves toward the deceleration proximity switch _B2 , and the switch _S2 detects the loosening of the pile warp yarns A.

The energization of the motor M is repeated by dividing the AC power supply cycle into a predetermined number of cycles, and within the divided number of cycles, the energization off timing is set by both proximity switches _S1 and _S2 , depending on the pile warp yarns A. The tension of the pile warp yarns A is controlled by accelerating or decelerating the motor M by turning on and off the current.

FIGS. 4A to 4C show waveforms of the AC power source and on/off timing.

For example, even with a 60-cycle AC power supply, the power supply to the motor M is divided into cycles of 0.2 seconds as shown in FIG. 4A, and by repeating this cycle, the motor M can be driven at all times.

Further, within the divided number of cycles, the off timing setting by both proximity switches S ₁ and S ₂ is performed as follows.

The drive of the motor M according to the intermediate cycle number of the number of cycles divided as shown in FIG.
As shown in Figures 1 and 3, both proximity switches _S1 and _S2 are kept at exactly the intermediate position, so that both proximity switches _S1 and _S2 are not operated.

Therefore, when the tension of the pile warp yarns A is such that the dock 11 is located between the proximity switches _S1 and _S2 , the motor M is energized within the divided number of cycles as shown in FIG. 4A. is turned on for the reference intermediate setting waveform and turned off for the rest, and this is repeated every divided cycle number.

In addition, in the number of divided cycles, the motor M rotates in the first half, rotates by inertia and decelerates in the second half. Match.

As shown in FIG. 4B, the deceleration proximity switch _S2 is connected so as to turn off the current before the reference intermediate set wave number.

Therefore, the tension of the pile warp A becomes loose, and the tension of the pile warp A becomes loose.
1 approaches the deceleration proximity switch _S2 , and when this switch _S2 is activated, the number of energization cycles decreases as shown in FIG. 4B, and the motor M rotates for a short time.
The coasting period becomes longer, resulting in deceleration.

As shown in Fig. 4C, the acceleration proximity switch _S1 is for turning off the current after the standard intermediate setting wave number, and when the tension of the pile warp yarns A becomes tense, the dock 11 switches the proximity switch _S1 . , this switch S ₁ remains energized while detecting the dock 11 .

Therefore, when the tension of the pile warp yarns A increases, the rotation of the motor M becomes longer, and the rotation of the roll 1 is accelerated.

Although only the tension of the pile warp A is controlled in FIG. 1, the tension of the ground warp B can also be controlled in the same manner.

In addition, in Fig. 3, a limit switch _S3 for excessive thread tension for stopping the loom and a limit switch _S4 for stopping the yarn feed are arranged so as to detect the pile warp A while it is moving. .

The warp tension control method of the present invention is carried out using the above-mentioned control mechanism, and when the pile warp A and the ground warp B are wound by the operation of the loom, the motor M whose speed has been adjusted in advance causes the rolls to move. 1
The pile warp threads A are sent out by rotating the threads.

During the towel loom process, the tension of the pile warp yarns A constantly changes, and the tension roll 3 swings following the change in tension, and the tension is adjusted by the dot 11 and proximity switches S ₁ and S ₂ . Detect changes in

When the tension of the pile warp A becomes tight, the acceleration proximity switch _S1 detects this and increases the number of cycles to rotate the motor M; conversely, when the tension becomes loose, the deceleration proximity switch _S2 increases the number of cycles. Reduce.

Therefore, the pile warp delivery roll 1 accelerates or decelerates in accordance with the change in the tension of the pile warp A, averages out the amount of feed of the pile warp A, and keeps it constant, so as to prevent an increase in tension during pile formation. It is possible to quickly respond to any situation and weave towels with uniform pile height.

〔effect〕

As described above, according to the present invention, the energization of the motor is divided into a predetermined number of cycles and repeated, and within the divided cycles, the off timing of the energization is changed in accordance with the tension fluctuation, and the warp threads are By accelerating and decelerating the feed, the warp feed amount can be averaged and kept constant, and a constant tension can be maintained from the warp winding diameter to the end, and the pile height can be kept constant. Constant towels can be woven.

Further, since the warp tension is averaged by electrical control of the motor, speed control can be performed at low cost.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing a combination of a loom and a control mechanism, Fig. 2 is an enlarged front view of the main parts of the same, Fig. 3 is a plan view of the same, Fig. 4 A to C are waveform diagrams of control cycles, FIG. 5 is an explanatory diagram of woven terry cloth. 1...Warp delivery roll, 3...Tension roll, 11...Dock, A...Pile warp, B
... Ground warp, C ... Weft, S ₁ , S ₂ ... Proximity switch.

Claims (1)

[Scope of Claims] 1. In a loom in which a warp delivery roll is driven by a motor, energization of the motor is repeated in a predetermined number of cycles, and
The warp tension fluctuation is detected by a tension roll and a switch, and the switch changes the off timing within the divided cycle number according to the warp tension fluctuation, and the motor is turned on and off to increase speed or A warp tension control method for a loom, characterized by controlling warp tension by decelerating the warp threads. 2. According to claim 1, the motor drive according to the intermediate cycle number of the divided cycle numbers is made to match the warp delivery speed at the warp intermediate winding diameter of the delivery roll, and the off timing is changed based on this intermediate cycle number. The warp tension control method of the described loom.