JP3286688B2 - Fiber bundle shape abnormality detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a process for packing a fiber bundle, which has been crimped and dried after spinning, and sent to a stacking device using a feed roll to pack the fiber bundle. The present invention relates to a fiber bundle shape abnormality detection device for detecting whether a fiber bundle has a predetermined shape. The target fiber bundle includes, for example, a fiber bundle for a cigarette filter, but is also applicable to a fiber bundle for other uses.

[0002]

2. Description of the Related Art Tobacco filter fiber bundle (filter tow), which is one of the general fiber bundles, is compressed and packed in a continuous band form, sent to a filter processing plant, and wound up. After being processed into a plug through a process called "tobacco", it is finally attached to the tobacco at a tobacco factory to produce a tobacco with a filter.

In the manufacturing process of this filter tow,
The fiber bundle that has been crimped and dried to form a belt after spinning is conveyed to a deposition device using a feed roll, and after a certain amount is deposited, compressed and packed to obtain a product. In the course of this conveyance, the fiber bundle may cause shape abnormality such as twisting. When such a shape abnormality occurs, it causes troubles such as defective opening in the above-described winding process. Conventionally, the detection of a shape abnormality is performed by visual observation by a supervisor, but since the probability of occurrence of the shape abnormality is extremely low, it is difficult to allocate a dedicated supervisor, in terms of cost and the like, Therefore, it is discovered only when coincidence that the observer patrols when a shape abnormality occurs overlaps.

[0004]

As means for automatically detecting the occurrence of a shape abnormality as described above, the thickness or width of a target fiber bundle is continuously measured by a detector, and the output signal thereof is set to a predetermined value. A device that issues an alarm when an upper limit or a lower limit, i.e., a threshold is exceeded, is conceivable. In such an apparatus, the setting of the upper limit and the lower limit is generally performed manually.

[0005] However, the signal from the detector may fluctuate due to a change with time of the detector or the like. It is also conceivable that the sensitivity may decrease due to dirt and the like. Furthermore, due to individual differences between the detectors, the average value of the output signal is different even in a normal state. For this reason, the setting operation of the threshold value is complicated and difficult, and it is necessary to frequently correct it once set. For this reason, although it is theoretically possible to automatically detect the abnormal shape of the fiber bundle,
For the reasons described above, installation and maintenance work is troublesome,
At present, it has not been put to practical use.

In view of the foregoing, the present invention does not need to artificially change the setting of the threshold value even when the characteristic difference of the detector or the change over time occurs, and automatically detects the abnormal shape of the fiber bundle. It is an object of the present invention to provide a highly reliable fiber bundle shape abnormality detecting device which can be performed at a high speed.

[0007]

In order to achieve the above-mentioned object, the present invention provides a method for producing a fiber bundle in a processing step in which a bundle of fibers which is crimped and dried after spinning is sent to a stacking device using a feed roll and packed. an apparatus for detecting the abnormal shape of the bundle, and measuring means for measuring the thickness or width of the fiber bundle continuously calculating means for obtaining a threshold value based on the measurement value measured by said measuring means, said Performs calculations continuously
Setting means for returning and setting a threshold value; abnormality determining means for detecting a shape abnormality of the fiber bundle from the measured value and the threshold value; and notification means for generating an alarm when the abnormality determining means determines that the shape is abnormal. And characterized in that:

[0008]

Since the signal from the detector contains irregular noise, it is necessary to consider the noise intensity when automatically setting the threshold. For this reason, it is necessary to obtain a high-quality signal with little noise and to eliminate the influence of noise as much as possible in signal processing. Also,
Since the signal contains sporadic strong noise, if an alarm is issued only by a simple comparison with a threshold, the occurrence rate of false alarms increases, and the signal becomes unpractical.

In the present invention, the threshold value is set by repeatedly and automatically calculating the threshold value. Therefore, the threshold value is automatically adjusted by following a gradual change in the signal level caused by a characteristic difference of the detector or a change with time. To set. For this reason,
It is possible to detect the shape abnormality of the fiber bundle online without the need for manual operation.

[0010]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a fiber bundle shape abnormality detecting device according to the present invention. In FIG. 1, a fiber bundle denoted by reference numeral 1 is conveyed in one direction while being guided by guides 2 and 3, and detectors including a light projector 4 and a light receiver 5 are arranged on both sides of the fiber bundle 1. . The light projector 4 and the light receiver 5 are arranged such that their optical axes coincide with each other, and the fiber bundle 1 passes through this optical axis. When installing the detector, it is desirable to select a place where there is little fluctuation such as fluctuation of the fiber bundle. In this embodiment, the guides 2 and 3 are provided before and after the detector for the purpose of reducing the fluctuation of the fiber bundle and preventing the fiber bundle from protruding from the detection range of the detector. If stable, one or both can be omitted.

FIG. 1 shows a configuration for detecting the thickness of the fiber bundle. However, a detector may be provided at a position where the width of the fiber bundle can be detected. It may be configured to detect both widths. Further, a cover may be provided or air may be blown for the purpose of dust prevention of the detector portion.

The amplifier 6 supplies a current for light emission to the light projector 4, amplifies a signal from the light receiver 5, and supplies it to an A / D converter 7 of the processing device. This processing device
Along with the A / D converter 7, a timer / counter board 8,
Ethernet board 9, digital signal output board 1
0, a speech synthesizer 11 for alarm, and a computer 12 for calculation. Reference numeral 13 denotes an Ethernet cable, 14 denotes a digital signal output cable, 15 denotes a loudspeaker, and 16 denotes an audio output cable.

The signal supplied from the amplifier 6 to the A / D converter 7 is passed to the computer 12 as digital value data DT. In this embodiment, the timer / counter board 8 is used to interrupt, for example, about every 2 milliseconds, perform measurement, and forcibly perform signal conversion and data processing. However, if the processing speed does not particularly matter, such a forced interrupt need not be performed. Further, the cycle of data processing may be flexibly changed in a range of several seconds to several hundred microseconds depending on the state of the signal.

Although a single computer may monitor a plurality of detectors, in order to avoid complication, the following description focuses on one detector and shows the data processing procedure in FIG. This will be described with reference to the flowchart of FIG.

Next, prior to the description of the present invention, a method of detecting an abnormality of the present invention will be described. In the present invention, the obtained data DT has considerable variation. Therefore, a threshold value is set in advance at the approximate center value of the variation, and when the obtained data DT exceeds the threshold value, the value of the counter is incremented. Is not exceeded, the value of the counter is decremented, and when the value of the counter reaches a predetermined value, the state is determined to be abnormal. During this time, the threshold value is continuously calculated and corrected according to the obtained data DT, and the threshold value is updated.
Then, even if the state becomes abnormal, if the value of the counter returns to 0, it is determined that the state has returned to the steady (normal) state.

Now, in FIG. 2, in the start state,
In step S1, the internal state is steady, the counter value P is set to 0 (step S1), and data from the photodetector 5 of the detector shown in FIG. 1 is supplied to the A / D converter 7 via the amplifier 6; Here, A / D conversion is performed (step S2),
Then, it is input to the computer 12 (step S
3).

The computer 12 receives the data D
T is compared with a preset threshold value. In the following description,
A state in which the data DT exceeds the threshold is represented as ON, and a state in which the data DT does not exceed the threshold is represented as OFF. Then, when a certain condition is satisfied, the start or end of the abnormality (both are collectively described as an “event”) is determined.

The computer 12 uses a counter for event detection, and determines that an event has occurred when certain conditions are satisfied. Further, the computer 12 holds a “steady state” and an “abnormality detection state” as internal states, and processes the received data DT according to the internal states as follows.

First, in the "steady state", step S4
, The average value AV of the current data DT is updated.
The average value can be determined according to the following equation. AV (i) = P × AV (i−1) + Q × DT (i) (1) Here, P + Q = 1, and P> 0 and Q> 0.

As another method, AV (i) = ΣDT (n) / N (2) may be calculated based on the latest N actual measured values.

Next, the average value of the fluctuation range of the current data is updated. The average value can be determined according to the following equation. DV (i) = p × DV (i−1) + q × | DT (i) −AV (i) | (3) where p + q = 1, p> 0, q> 0, and , |
X | represents the absolute value of X. Alternatively, instead of the equation (1), a root mean square instead of an absolute value may be used.

Subsequently, based on the obtained value, the threshold value is periodically updated at a constant period. It is not necessary to set the threshold value every time, but it is desirable to update the threshold value at the latest every minute. In setting the threshold value, for example, threshold value = AV + DV × f (in the case of increase) threshold value = AV−DV × f (in the case of decrease) in accordance with the characteristic of whether the data value increases or decreases when an abnormality occurs. Set as follows. Here, f is a parameter for setting a threshold value, and when it is reduced, the sensitivity increases but the possibility of false notification increases. Next, the data DT is compared with a threshold value and converted into a logical value indicating whether or not the threshold value is exceeded. The threshold updating process is performed in steps S21 to S21 of the flowchart of FIG.
23.

Next, in step S5, ON / OFF determination is made according to the logical value obtained in step S4. If it is OFF, the counter is counted down in step S6, and if the count value reaches zero, an abnormal condition is detected. Is completed, and the internal state is returned to the “steady state”.

On the other hand, if it is determined to be ON in step S5, an operation of counting up (incrementing) the counter is performed (step S7), and it is determined in step S8 whether the counter value P has reached P1. As a result,
If the counter value P has not reached P1, it is determined that the vehicle is not in an abnormal state, and the internal state is set to a "steady state" as in step S6. If the value of the counter value P has reached the preset value P1, step S9
Then, the value P of the counter is set to a predetermined value P2. Next, in step S10, the internal state is set to an event occurrence state, and the subsequent processing is shifted to an event processing routine.

On the other hand, if it is determined in step S3 that an abnormality has been detected, ON / OFF determination is made in step S11. If it is determined that the switch is ON, the counter value P is set to P2 in step S12. The next data DT is detected. If it is OFF, the counter value is counted down (decremented) in step S13, and when the counter value P becomes 0, the internal state is changed to the steady state in step S15, and then the end of the event is notified in step S16. I do.

In this embodiment, when an event is detected, the event is displayed on the monitor screen as shown in step S33, and necessary items are recorded in an external database via Ethernet (step S36). The processing from the acquisition of the event information to the recording in the database is shown in steps S31 to S36 of the flowchart of FIG. Then, as shown in FIG. 4, at the same time as recording in the database (step S36), a warning is issued by voice output (step S35), and further, the digital signal is output to an external device via the digital signal output board 10 (FIG. 1). Send a signal. However, these devices are not essential, and other alternative devices may be used as long as they can notify or record the event to workers and / or external equipment.

As described above, the fiber bundle shape abnormality detecting apparatus of the present invention provides a fiber bundle that has been crimped after spinning and then dried and sent to a stacking device using a feed roll for packing. An apparatus for detecting a shape abnormality, a measuring means for continuously measuring the thickness or width of the fiber bundle, a calculating means for obtaining a threshold based on the measurement value measured by the measuring means, and the calculation Continuously repeating rows
Setting means for setting a threshold value, an abnormality determining means for detecting the shape abnormality of the fiber bundle from the measured value and the threshold value, and a notifying means for generating an alarm when the abnormality determining means determines that the shape is abnormal. It consists of.

[0028]

As described above, according to the present invention, by setting the parameters to appropriate values first, the detector can be placed without adjusting the detecting device thereafter. It is possible to eliminate an error factor such as noise generated due to an environment or the like, and detect a fiber bundle shape abnormality with high accuracy. For this reason, maintenance of the device is facilitated, and the quality of the product can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a fiber bundle shape abnormality detecting device according to the present invention.

FIG. 2 is a flowchart showing an event detection operation in the device of FIG.

FIG. 3 is a flowchart showing a threshold setting operation in the apparatus of FIG. 1;

FIG. 4 is a flowchart showing an event processing operation in the device of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fiber bundle 2, 3 Guide 4 Projector 5 Receiver 6 Amplifier 7 A / D converter 8 Timer / Counter board 9 Ethernet board 10 Digital signal output board 11 Voice synthesizer 12 Computer 15 Loudspeaker 16 Voice output cable

Claims (1)

(57) [Claims] 1. A device for detecting a shape abnormality of a fiber bundle in a processing step in which a fiber bundle which is crimped and dried after spinning is sent to a stacking device using a feed roll and packed. measuring means for measuring the thickness or width of the fiber bundle continuously calculating means for obtaining a threshold value based on the measurement value measured by said measuring means, repeatedly the operation continuously
Setting means for returning and setting a threshold value; abnormality determining means for detecting a shape abnormality of the fiber bundle from the measured value and the threshold value; and notification means for generating an alarm when the abnormality determining means determines that the shape is abnormal. And a fiber bundle shape abnormality detecting device.