JP2002310822A - Abnormality detecting method for yarn drawing and false twisting machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method capable of improving the cost of measuring personnel, individual difference in technical level, and safety in the detection of facility abnormality of a yarn drawing and false twisting machine. SOLUTION: This abnormality detecting method for yarn drawing and false twisting machine comprises, detecting a facility abnormality generated in a power transmission apparatus from the fluctuating state of current carried to a drive motor, in the yarn drawing and false twisting machine for rotating a plurality of yarn grasping rolls for regulating the traveling speed of a yarn arranged in the flowing direction of the yarn by speed-changing and branching the rotating power of one drive motor through a plurality of power transmission apparatuses, and performing a yarn working treatment such as drawing, false twisting, intermingling or the like between the yarn grasping rolls; and analyzing the frequency of fluctuation of the current, thereby specifying the abnormality generation part of the power transmission apparatus.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting equipment abnormality in a yarn drawing false twisting machine.

[0002]

2. Description of the Related Art A yarn drawing false twisting machine is provided with a plurality of yarn gripping rolls which regulate the traveling speed of a yarn arranged in the flow direction of a yarn. In the process of passing yarn between rolls by a yarn processing device arranged in between, it is a machine that adds characteristics according to its use.In the processing process, it is possible to increase the strength by stretching the yarn, Processing such as imparting crunchiness by twisting and imparting convergence by confounding is applied. In general, stretching and false twisting are performed simultaneously, a false twisting device is provided between two yarn gripping rolls having different peripheral speeds, twisting is generated between the false twisting device and the upstream yarn gripping roll, and stretching is performed. The twisting state is thermally fixed by a heating device provided there, and the twist is returned between the false twisting device and the downstream yarn gripping roll. Entangling is provided with an entanglement device between two yarn gripping rolls with different peripheral speeds,
Therefore, confounding is given. In the yarn drawing false twisting machine, the plurality of yarn gripping rolls are connected to one drive source, in particular, the rotational power of one electric motor, by a power transmission device such as a gear, a shaft, a belt, a pulley, a chain, and a sprocket. The drive is performed by transmitting the speed and branching via the.

In such a yarn drawing false twisting machine, a part of a power transmission device is used to fix equipment abnormalities due to deterioration of members, for example, gear and sprocket tooth missing, shaft and gear, pulley, and sprocket. If the key part is worn, the power transmission system will rattle, the rotation speed of the yarn gripping roll will fluctuate, and the yarn tension during processing will fluctuate, resulting in abnormal yarn quality. The problem arises. Quality abnormalities appear as uneven yarn thickness when the tension fluctuation occurs during drawing, and appear as uneven yarn thickness or unevenness when drawn during false twisting and occur during confounding. Appears as confounding unevenness. Further, in some cases, there is a problem in that the operation of the machine itself is stopped before it becomes apparent as a quality abnormality, resulting in a production loss.

[0004] It is required to detect equipment abnormalities before the problem of these abnormalities occurs. Conventionally, as a method for detecting equipment abnormalities, a qualitative, stethoscope is placed near a power transmission device to generate abnormal noise by an acoustic sound. A method of detecting and quantitatively measuring a vibration value with a vibrometer were performed.

[0005] However, in the method using hearing sound, there are many parts depending on the senses, there are individual differences in technical level, and an abnormality in the equipment of the stretch false twisting machine is sometimes overlooked. Further, the drawing false twisting machine has a plurality of yarn gripping rolls at positions separated from each other in the yarn traveling direction, and further arranges a large number of the yarn gripping rolls in parallel in the yarn traveling direction. In general, the power transmission device is configured to be capable of processing a large number of yarns at the same time, so that the power transmission device is complicated and has a long connection. Therefore, there are many points to be measured in both the method of measuring the sound and the vibration, so that many measuring steps are required, and the cost merit is low. In addition, it is also the work near the rotating body,
There were also safety issues.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to detect an abnormality in a yarn drawing false twisting machine.
It is an object of the present invention to provide a method that can improve the cost of measurement personnel, individual differences in technical level, and safety.

[0007]

In order to solve the above-mentioned problems, a method for detecting an abnormality in a yarn drawing false twisting machine according to the present invention uses the rotational power of one drive motor via a plurality of power transmission devices. By changing the speed and branching, a plurality of yarn gripping rolls, which are arranged in the flow direction of the yarn and define the running speed of the yarn, are rotationally driven, and stretched, false twisted, and entangled between the yarn gripping rolls. In a yarn drawing false twisting machine that performs a yarn processing such as the above, a method of detecting equipment abnormality occurring in a power transmission device from a fluctuation state of a current flowing through the drive motor is provided.

In the method of the present invention, in addition to the above-described means, it is preferable that the frequency at which the current fluctuates is analyzed so as to specify a portion of the power transmission device where an abnormality has occurred.

In the method for detecting an abnormality of the yarn drawing false twisting machine according to the present invention as described above, a part of the power transmission equipment of the yarn drawing false twisting machine causes an equipment abnormality due to deterioration of members or the like. However, when the power transmission system rattles and the rotational speed of the yarn gripping roll fluctuates, the influence of torque fluctuation also affects the drive motor that is the starting point of the power, and the current value of the drive motor fluctuates. Therefore, by measuring and grasping the amount of change in the current value, it is possible to detect a facility abnormality occurring in the power transmission device. Furthermore, since the power transmission device has individual rotation frequencies, it is possible to identify a location in the power transmission device where an abnormality has occurred by analyzing the fluctuation frequency of the current value. According to this method, abnormality of the entire equipment can be quantitatively and safely diagnosed only by measuring one point of the current value of the drive motor, and all the problems of the cost of measuring personnel, individual differences in technical level, and safety are solved. be able to.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with preferred embodiments. In carrying out the method according to the present invention, for example, an apparatus having the following configuration is used. That is, the configuration includes an ammeter for measuring the current of the drive motor, and analysis means for quantifying the fluctuation component from the current value measured by the ammeter. Any type of ammeter can be used as long as it can measure the current value and has sufficient accuracy to capture the fluctuation of the current value, but it measures the current value from the magnetic field generated around the power wiring of the drive motor A clamp-type ammeter is desirable because of its high safety and workability. As a means of analysis, a simple method of displaying the current value on an electric display screen such as an oscilloscope or a recording sheet and directly measuring the amount of fluctuation of the current value may be used. , And the current variation may be automatically calculated by a calculation program prepared in advance, and then read. More preferably, the current value data converted into digital information is frequency-analyzed, and the fluctuation component is converted into a frequency spectrum form separated for each frequency, and then displayed and read. It is possible to measure and compare this frequency with the rotation frequency of the rotating body in each driving device, and it is possible to specify the location where the abnormality has occurred, which is more preferable.

[0011] In order to detect the equipment abnormality of the yarn drawing false twisting machine using the above-mentioned ammeter and analysis means, an ammeter is attached to the power wiring of a motor for driving the yarn drawing false twisting machine. Then, the fluctuation amount of the current is read from the obtained current value data by using the analysis means. For example, this is performed periodically, the amount of current fluctuation is displayed as a graph with respect to the elapsed time, and compared with the results of quality abnormalities and machine stoppages that occurred during the measurement period, the level before the problem became apparent Then, a threshold value for determining that the equipment is abnormal is set, and thereafter, when the current fluctuation value exceeds the threshold value, it is determined that the equipment is abnormal. At a stage before such a threshold value is provided, the rate of change of the current fluctuation value may be monitored, and an extremely large value may be determined as a facility abnormality. More preferably, the current value data obtained therefrom is subjected to frequency analysis, and the fluctuation component is converted into a frequency spectrum form separated for each frequency, and then displayed and read. By comparing the rotation frequency of each rotator with the rotation frequency, it is possible to specify the location where the abnormality has occurred, which is more preferable.

[0012]

EXAMPLE 1 FIG. 1 shows a schematic configuration of a target yarn-drawing false twisting machine for performing an abnormality detection method of the yarn-drawing false-twisting machine according to one embodiment of the present invention. The yarn drawing false twisting machine is
Drive motor 1, power transmission unit 2, yarn processing / winding unit 3
Consists of The drive motor 1 is a three-phase induction motor, and the rotational power output from the motor 1 is applied to the shaft 4 (4-a, 4-b, 4-c, 4-d, 4-
t, 4-y, 4-z, 4-α, 4-θ, etc.), gear 5 (5
-A, 5-b1, 5-b2, 5-c, 5-d, 5-t,
5-y, 5-z), sprocket 6 (6-α, 6-
θ), transmitted and branched via a plurality of power transmission devices (rotary power transmissions) constituted by a chain 7 and the like, each of which is shifted to a speed according to production conditions, to the yarn processing / winding unit 3. The first thread gripping roller 8, the second thread gripping roller 9, the third thread gripping roller 10, the winding roller 11
Are driven at predetermined rotation speeds.

As the flow of the yarn processing, the unprocessed yarn 16 is sent by the first yarn gripping roller 8, and the yarn is drawn by the difference in rotation speed between the first yarn gripping roller 8 and the second yarn gripping roller 9. At the same time, false twisting is performed by the false twisting device 12, and heat setting is performed by the heater 13 and the cooling plate 14. Next, the yarn tension is relaxed by the difference in rotation speed between the second yarn gripping roller 9 and the third yarn roller 10, and during this time, entanglement is performed by the entanglement device 15, and winding is performed by the winding roller 11. To produce a drawn false twisted yarn package 17.

In measuring and analyzing the amount of current fluctuation of the drive motor 1, as shown in FIG. 2, a clamp type ammeter 18 is attached to one of the three-phase wires connected to the drive motor 1, and the detected current raw waveform The data displayed on the digital oscilloscope 19 was printed on paper by the printer 20, and the current fluctuation H was measured. As shown in FIG. 3, the current was obtained by reading the amount of fluctuation in the amplitude from the raw current waveform.

With such a configuration, the fluctuation amount H was measured every other month for a plurality of yarn drawing false twisting machines, and the value was graphed with time. FIG. 4 shows the representatives of the first and second units. First, confounding abnormality occurred in the first unit 9 months after the start of measurement. Here, in order to specify an abnormal part, as shown in FIG. 5, the frequency is calculated using an FFT (Fast Fourier Transform) analyzer 21 (manufactured by Ono Sokki Co., Ltd., CF-3600) which decomposes the raw current waveform data into frequency components. The image was disassembled, displayed, printed on paper with the printer 20, and analyzed by comparing the calculated value of the rotation frequency of each part.

FIG. 6 shows the results of decomposition of the frequency components of the current waveform, and Table 1 shows the calculated values of the rotational frequency of the main drive transmission portion of the yarn drawing false twisting machine.

[0017]

[Table 1]

Here, since the gear 5, the sprocket 6 and the like are always fixed to the shaft 4 and rotate, the rotation frequency of the shaft 4 is shown as a representative. As shown in FIG. 6, the FFT transform data has a shape having sideband components symmetrical to the left and right around a carrier current at a power supply frequency of 60 Hz, and the difference between the frequency of the sideband components and the power supply frequency is shown. The absolute value indicates the frequency of the load fluctuation, and in this case, the frequency with the largest fluctuation amount is 9.1 Hz. The frequency 9.1 Hz of the load fluctuation coincided with the rotation frequency of the 4-t axis in Table 1, and it was expected that the location of the confounding abnormality was a 4-t axis related part. Therefore, the drive transmission unit disassembly inspection result shows that the gear 5-t fixed to the 4-t axis
There was a missing tooth, and the predicted abnormal occurrence site and the actual abnormal site coincided by frequency analysis. Based on the result of the quality abnormality of the first unit, 3 [A] in FIG. 4 at which the current fluctuation started to increase rapidly was determined as the equipment abnormality threshold.

Next, 20 months after the start of the measurement, since the threshold value of 3 [A] was exceeded in the No. 2 drawing false twister (FIG. 4), the FFT analyzer 21 was used in the same manner as when the abnormality occurred in the No. 1 machine. The current waveform was frequency-resolved, and the display was printed on paper by the printer 20. FIG. 7 shows the result. The frequency at which the load change was large was 19.2 Hz. As a result of comparison with Table 1, it was predicted that the 4-c or 4-d axis-related portion was abnormal. As in the case of the equipment failure, as a result of the power transmission part disassembly inspection, severe wear was observed on the key connecting the 4-d shaft and the gear 5-d. After that, by replacing this part with a new one, it was possible to prevent damage such as abnormal quality.

As described above, the rotational power of one drive motor is shifted / branched through a plurality of power transmission devices, thereby defining the running speed of the yarn arranged in the flow direction of the yarn. Rotate and drive multiple yarn gripping rolls,
In a yarn drawing false twisting machine that performs yarn processing such as drawing, false twisting, and entanglement between the yarn gripping rolls, a device abnormality occurring in a power transmission device is detected from a fluctuation state of a current flowing through the drive motor. Further, it has been clarified that by analyzing the frequency of the fluctuation of the current, it is possible to identify the abnormality occurrence site of the power transmission device.

[0021]

As described above, according to the method for detecting an abnormality of the yarn drawing false twisting machine according to the present invention, the measurement of the current value of the drive motor at one point only requires the measurement of the yarn drawing false twisting machine. An abnormality in the power transmission equipment can be detected, and the abnormal part can be identified by analyzing the frequency of the current fluctuation. As a result, it is possible to solve all the costs of equipment diagnosis personnel, individual differences in technical level, and safety issues.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a yarn drawing false twisting machine which is an object in carrying out a method of the present invention.

FIG. 2 is a schematic configuration diagram showing a method of measuring a current fluctuation amount of a drive motor in the apparatus of FIG.

FIG. 3 is a chart showing a measurement example of a current fluctuation amount H;

FIG. 4 is a graph showing a change over time of a current fluctuation amount H of a yarn drawing false twisting machine to be measured.

FIG. 5 is a schematic configuration diagram illustrating a method of measuring a current frequency component.

FIG. 6 is a diagram showing a frequency decomposition result of a current waveform at the time of abnormal confounding of the first yarn drawing false twisting machine as a measurement target.

FIG. 7 is a diagram showing a frequency decomposition result of a current waveform when a current fluctuation amount exceeds a threshold value in a yarn drawing false twisting machine No. 2 as a measurement target.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drive motor 2 Power transmission part 3 Thread processing / winding part 4 (4-a ‥‥ 4θ) Shaft 5 (5-a ‥‥ 5z) Gear 6 (6-α, 6-θ) Sprocket 7 Chain 8 1 yarn gripping roller 9 second yarn gripping roller 10 third yarn gripping roller 11 take-up roller 12 false twisting device 13 heater 14 cooling plate 15 entanglement device 16 unprocessed yarn 17 stretched false twisted yarn package 18 clamp type current Total 19 Digital oscilloscope 20 Printer 21 FFT analyzer

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Ryuichi Nakatani, 1st Kita-shi, Kita-shi, Tatsunokuchi, Nomi-gun, Ishikawa Pref. Inside the Ishikawa Plant (72) Inventor Shunichi Minami 1st, Kita-shi, Tatsunokuchi, Nomi-gun, Ishikawa Toray F term in Ishikawa Plant Co., Ltd. (reference) 2F051 AA16 AB06 CA03 4L036 PA14 UA25

Claims (2)

[Claims] 1. A plurality of yarns, which are arranged in the direction of yarn flow and which regulate the running speed of the yarn, by rotating / branching the rotational power of one drive motor via a plurality of power transmission devices. In a yarn drawing false twisting machine for rotating a yarn gripping roll and performing yarn processing such as drawing, false twisting, and entanglement between the yarn gripping rolls, power transmission is performed based on a fluctuation state of a current flowing through the drive motor. A method for detecting an abnormality of a yarn drawing false twisting machine, comprising detecting an equipment abnormality occurring in a device. 2. The method for detecting an abnormality in a yarn drawing false twisting machine according to claim 1, wherein an abnormality occurrence site of the power transmission device is identified by analyzing a frequency of the fluctuation of the current.