JP3691596B2 - Corrugated cardboard sheet adhesion failure detection device - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to an apparatus for detecting an adhesion failure caused by a difference in traveling speed or a traveling amount between a front liner paper and a single-sided corrugated sheet in the process of producing the corrugated sheet.
[0002]
[Prior art]
As is well known, in the process of manufacturing a corrugated cardboard sheet, there is a step of laminating the single-sided corrugated cardboard sheet and the front liner paper by a laminating machine called a double facer. In front of this laminating machine, a gluing device is installed for adhering glue to the top of the core paper on which the single-sided cardboard sheet is stepped.
[0003]
As for the gluing device, there are those disclosed in various publications such as JP-A-60-165235. In any case, the gluing device rotates the glue roll soaked in the container supplied with the glue, adjusts the amount of glue with the doctor roll, and then adjusts the amount of glue on the top of the corrugated cardboard sheet. The glue is attached to the glue roll with an appropriate pressure, and the front liner paper to be bonded to the glue roll is passed between the guide roll and the guide roll to be bonded to the top of the core paper. In general, this bonding is performed by pulling the front liner paper under a suitable pressure between the single-sided corrugated cardboard sheet and the front liner paper without causing a shift between them, and with a tensile force that does not deform the stepped portion. It is made to run, and it is pasted.
[0004]
[Problems to be solved by the invention]
By the way, when the front liner paper is bonded to the single-sided cardboard sheet glued to the top of the core paper by the gluing device described above, the single-sided cardboard sheet and the front liner paper are both pulled by a double facer feed belt with a constant tension and run. Lamination is performed. At this time, the back side of the single-sided cardboard sheet and the front liner paper is pulled with a constant braking force, while a constant tension is applied to the single-sided cardboard sheet and the front liner paper and is fed to the double facer at the same speed.
[0005]
However, a defective sheet due to adhesive displacement due to a difference between the speed of the front liner paper and the single-sided cardboard sheet before the double facer bonding process due to fluctuations in the speed of the device or the joining of the front liner paper. Produce.
[0006]
Such a state is shown in FIG. In the figure, the black dots are the adhesive applied to the top of the core paper on which the single-sided cardboard sheet b is stepped. Initially, the running speed is higher than the single-sided cardboard sheet b and the tension of the front liner paper c, which was slackening before the pasting process, is increased on the upstream side. In contrast, it can be seen that the top of the core paper of the single-sided corrugated cardboard sheet b and the front liner paper c are not well bonded by the adhesive. Since the core paper and the front liner paper are not bonded on the entire surface, but are bonded to the front liner paper only at the top of the core paper, if the front liner paper is displaced as described above, adhesion failure occurs.
[0007]
However, in the past, there was no inspection of poor adhesion by detecting the speed difference between the front liner paper and the single-sided corrugated sheet immediately before the pasting process, and it was continuously performed at a high speed. There has been a problem in that defective corrugated cardboard sheets due to poor adhesion are mixed into the produced corrugated cardboard sheets.
[0008]
In addition, once the single-sided corrugated cardboard sheet b is once covered with the front liner paper c, there is also an inconvenience that it is impossible to determine a poorly bonded part.
[0009]
This invention detects a defective adhesion based on a difference in feeding speed or a travel amount between a front liner paper and a single-sided corrugated sheet in a corrugated sheet bonding process in a conventional corrugated sheet manufacturing process, and removes defective products caused by the defective adhesion. It is an object of the present invention to provide an adhesion failure detecting device that enables simple and economical cost.
[0010]
[Means for Solving the Problems]
As a means for solving the above-mentioned problem, the present invention obtains a difference between the detected amount and a speed sensor for detecting the traveling speed or traveling amount of the front liner paper and the single-sided corrugated sheet provided before the corrugated sheet bonding step. This is compared with a reference value with a comparator, and when the difference between the two becomes larger than the reference value, a bonding failure detection circuit that outputs a bonding failure detection signal between the front liner paper and the single-sided cardboard sheet, and this bonding This is a cardboard sheet adhesion failure detection device provided with a defective product removal unit that removes the adhesion failure portion based on the adhesion failure detection signal from the failure detection circuit .
[0011]
In the present invention, an adhesion failure is detected by a difference in travel speed or travel amount between the single-sided corrugated cardboard sheet and the front liner paper that is temporarily and instantaneously generated during normal travel of the corrugated cardboard sheet. In the bonding step of the corrugated cardboard sheet, the single-sided corrugated cardboard sheet coated with the adhesive is bonded to the front liner paper and dried with a heater.
[0012]
Due to mechanical malfunction during normal running before such a pasting process, the tension of the single-sided corrugated cardboard sheet and the front liner paper to be pasted on the single-sided corrugated sheet is temporarily or momentarily changed greatly. There is a case where the travel amount is greatly deviated and, therefore, adhesion failure occurs.
[0013]
The cause of such adhesion failure is that the drive motor of the guide roll that is rotating by driving temporarily trips and the rotation of the guide roll is stopped, so that the liner paper or single-sided cardboard sheet being guided is stopped. A base paper roll that supplies liner paper when the brake is applied and the running speed drops due to increased tension in the downstream laminating process, causing one to shift with respect to the other or when splicing on a mill roll stand There is a case where the traveling speed is lowered and the traveling deviation similarly occurs because the tension is increased in the laminating step on the downstream side due to the inertial resistance when switching from one to the other and the movement resistance of the guide roll.
[0014]
Such poor adhesion is detected as follows. The speed sensor detects the running speed or the running amount of the front liner sheet and the single-sided cardboard sheet, and these detection signals are sent to the adhesion failure detection circuit, and the difference signal between them is obtained by subtracting the other from one. This difference signal is sent to the comparator and compared with the reference signal. When the difference signal is larger than the reference signal, an adhesion failure detection signal is generated.
[0015]
The reference signal is a slight difference to the extent that the difference in travel speed or travel amount between the single-sided corrugated cardboard sheet and the front liner paper that occurs during normal travel is greater than the maximum value that can be considered within the normal range. Set as the corresponding signal. In addition, the maximum value of the difference between the traveling speed or the traveling amount that can be regarded as being within the normal range is determined as the maximum difference that does not cause poor adhesion.
[0016]
A control signal is output through the control unit in response to the output of the adhesion failure detection signal, and is used, for example, to operate the drive unit of the defect removal unit to remove the defective part.
[0017]
In addition, if slight deviations in adhesion due to instantaneous travel speed differences between the single-sided corrugated cardboard sheet and the front liner paper can be regarded as non-defective products, these travel speed differences will continue for a certain period of time and become the reference value. When exceeding, you may make it detect a poor adhesion part.
[0018]
In addition, in the case of the travel amount, the influence of the instantaneous speed difference fluctuation that can be regarded as good adhesion is canceled by integrating the speed signal, so that the defective adhesion portion can be detected more stably.
[0019]
Embodiment
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a schematic view of an example in which the apparatus including the process parts before and after the double facer of the corrugated cardboard manufacturing machine is provided with the adhesion failure detection apparatus of the embodiment. 1 is a heater, 2 is a gluing device, 3 is a double facer as a bonding process, 4 is a slitter scorer, 5 is a rotary cutter, 6 is a defective product removing unit, and 7 is a cylinder. Each of these components is known per se, and only an outline will be described here.
[0020]
In the illustrated apparatus, two single-sided corrugated cardboard sheets a and b and front liner paper c are sent to a heater 1 having three heat rolls 1a, 1b and 1c and heated to remove moisture unevenness, and then to a gluing device 2. Sent. In the gluing device 2, glue is attached to the top of each core sheet of the two single-sided cardboard sheets a and b by the two gluing units 2a and 2b, and the double facer 3 together with the front liner paper c fed by the heat roll 2c. These are fed to the feed rolls 3a and 3b on the inlet side of these and bonded together.
[0021]
Single-sided corrugated sheet a, b and front liner paper c are fed between feed rolls 3a, 3b provided at a predetermined interval in double facer 3 and bonded to each other to form corrugated sheet w, which is then placed on heater 3c. Is fed while being pulled by the feed belt 3d, is further caused to travel in the cooling section by the feed belt 3e, and is sent downstream by the feed rollers 3f and 3g.
[0022]
In the slitter scorer 4, slits and ruled lines are put in the corrugated cardboard sheet w at a predetermined interval, and after being cut into sheets w ₁ , w ₂ ,. 6 is passed to the further process. In the defective product removing unit 6, each sheet w ₁ , w ₂ ,... Passes only above the defective adhesion portion unless it is included, but if the defective portion is included, the defective portion is included. It is configured to rotate the driving plate 6a by driving the cylinder 7 to remove the sheet w _i.
[0023]
The defective product removal unit 6 shown in the figure is merely an example, and the traveling plate 6a is rotated by the cylinder 7. However, the traveling plate 6a can be moved horizontally or the sheet can be moved by another operating member. Of course, it is possible to adopt various types such as a lateral pushing type.
[0024]
The apparatus including the process part having the above-described configuration is provided with speed sensors Sb and Sc for detecting the traveling speeds of the single-sided corrugated cardboard sheet b and the front liner paper c, respectively, upstream of the feed rollers 3a and 3b on the inlet side of the double facer 3. Yes. The speed sensors Sb and Sc are generally called pulse generators. The speed sensors Sb and Sc are rotated by bringing a rotating roller into contact with a sheet such as front liner paper, and an electric signal generated by the rotation is output as a pulse signal representing a traveling speed. Of the form. As a method for detecting the speed, any method such as a method using a laser beam may be used.
[0025]
The adhesion failure detection circuit 10 shown in FIG. 2 detects signals from the speed sensors Sb and Sc as speed signals φb and φc by the travel detectors 8b and 8c to obtain a difference signal Δφ. A subtractor 9, a reference value setting unit 11 that sets a reference value and outputs a signal corresponding thereto, compares the difference signal Δφ with a signal corresponding to the reference value, and an absolute value corresponding to the difference signal Δφ is greater than the reference value In this case, it comprises a comparator that outputs an adhesion failure detection signal on the assumption that there is a speed difference that causes adhesion failure between the single-sided cardboard sheet b and the front liner paper c. This adhesion failure detection signal is sent as a control signal to the drive unit 14 of the defective product removal unit 6 via the control unit 13, and the drive unit 14 drives the cylinder 7 to remove the adhesion failure sheet downward.
[0026]
In addition, a failure detection signal from the comparator 12 is displayed on the display 15 indicating that a failure has been detected.
[0027]
The reference value setter 11 is a setter that can set a reference value to an arbitrary value by inputting data from the outside. The reference value is determined as a value larger than this limit value by actually measuring the limit value of the running speed difference at which the adhesion between the corrugated cardboard sheet b and the front liner sheet c becomes poor due to the magnitude of the speed difference. It is a thing.
[0028]
The adhesion failure detection device of the embodiment having the above configuration detects the adhesion failure of the corrugated cardboard sheet as follows. FIG. 3A shows a typical fluctuation graph of data in which a change in the speed difference between the single-sided corrugated cardboard sheet and the front liner paper is recorded by an apparatus for detecting sheet adhesion failure. In the figure, the horizontal axis represents time and the vertical axis represents the speed difference. The speed difference is-when the speed of the front liner paper is smaller than that of the single-sided cardboard sheet, and + when it is large. The speed difference often occurs on the-side due to the configuration of the corrugated board manufacturing machine.
[0029]
As an example of the cause of adhesion failure in the process of adhering the front liner paper to the single-sided cardboard sheet in the process of manufacturing the corrugated cardboard sheet, the drive motor of the drive roll that guides the front liner paper temporarily trips or the splicer As described above, fluctuations in the running state of the running paper at the time of paper splicing can be mentioned.
[0030]
For this reason, if the difference in travel speed between the single-sided corrugated cardboard sheet b and the front liner paper c exceeds the allowable limit, as shown in FIG. .
[0031]
Therefore, a reference value for the speed difference exceeding the limit is determined empirically in advance, and the defective adhesion portion can be electrically detected by detecting the speed difference exceeding the reference value. The illustrated graph shows a typical waveform of the measured data, and a reference value for detecting a defective adhesion portion is entered.
[0032]
It should be noted that the closer the reference value is set to the allowable maximum value, the more severe the defect detection. Although not shown in the figure, even if the speed difference exceeds the reference value very instantaneously, if it immediately returns to the reference value, there may be a case where it is not necessary to imitate the adhesion failure.
[0033]
In consideration of this, an adhesion failure detection signal may be generated when the speed difference continuously exceeds a reference value for a certain time.
[0034]
Note that the timing of traveling downstream to reach the defective product removal unit 6 after the defective adhesion portion is detected is obtained by the traveling speed signal φb of the single-sided cardboard sheet sent to the control unit 13, and at this timing Based on this, a control signal is sent to the drive unit 14 to operate the cylinder. By this operation, the guide plate 6a is rotated downward, and the poorly bonded sheet w _i is removed downward.
[0035]
In this embodiment, an adhesion failure signal is sent to the defective product removal unit 6, but the single-sided cardboard sheet and the front liner paper sent to the double facer 3 together with this unit or separately from this unit. The above control signal is sent to the tension adjustment feed roller and other tension adjustment units provided during the travel of the machine so that the tension that causes the feed speed fluctuation is adjusted at that moment so that no adhesion failure occurs. May be.
[0036]
In addition to the change in the speed difference, the defective adhesion portion can be detected based on the change in the travel amount as shown in FIG. The travel amount is obtained by multiplying the average speed within a certain sampling time by time.
[0037]
In this embodiment, the traveling detectors 8b and 8c convert the speed signal into a traveling amount and output a signal corresponding to the traveling amount, and the subtractor 9 obtains a signal of the difference between both traveling amounts. The reference value set in the reference value setter 11 is a value exceeding the allowable maximum value among the travel amount differences between the two caused by the difference in travel speed between the single-sided cardboard sheet and the front liner paper, and corresponds to this value. Is sent to the comparator 12. In the comparator 12, the signal corresponding to the reference value is compared with the difference signal of the traveling amount. Subsequent control operations are the same as those in the first embodiment.
[0038]
The defect detection circuit 10 of this embodiment is intended to detect an adhesion failure portion based on a travel amount difference instead of a speed difference. Detection of adhesion failure due to speed difference is a method of detecting a state change based on a signal change corresponding to a differential signal, whereas detection based on travel amount difference integrates the speed within a travel distance of at least the sampling time. This is performed based on fluctuations in the travel amount obtained in this way.
[0039]
Therefore, when it is not necessary to issue an adhesion failure detection signal at a very high speed difference that does not need to be imitated as an adhesion failure, detection based on a difference in travel amount is better. FIG. 3B shows a typical graph when a defective portion is generated due to a variation in the travel amount difference. As shown in the figure, the travel amount difference fluctuates within a maximum allowable range during normal travel, but the travel amount difference fluctuates greatly when a travel deviation that causes a poor adhesion portion occurs.
[0040]
As in the case of the first embodiment, a reference value that is a limit for causing an adhesion deviation that is considered to be an adhesion failure portion is measured in advance and determined for the fluctuation value of the travel amount difference. When the difference in travel amount exceeding the detected value is detected by the comparator 12, a signal is output as a result of an adhesion failure portion.
[0041]
Since the travel amount is generally measured as a cumulative value, once an adhesion failure portion is detected, the output values of the travel detectors 8b and 8c are further increased on the basis of the cumulative value as shown in the figure. The measured value of travel is accumulated.
[0042]
Since the operation controlled via the control unit 13 after the defective adhesion portion is detected is the same as that in the first embodiment, the description thereof is omitted.
[0043]
【effect】
As described above in detail, in the adhesion failure detection device of the present invention, the traveling speed difference or the traveling amount difference based on the signal from the speed sensor is compared with the reference value, and the traveling speed difference or the traveling amount difference is equal to or more than the reference value. detecting the sheet bonding failure of by detecting that became, from and configured to remove the reference value to distinguish the maximum value of the running speed difference or travel distance difference sheet during normal running causing no adhesive failure By setting as an appropriate value to be obtained, it is possible to reliably detect a bonding failure of the corrugated cardboard sheet by a simple method in the bonding process of the corrugated cardboard sheet, and control so that defective products are not removed or defective bonding occurs. This is advantageous in that it can greatly contribute to improving the quality of corrugated cardboard products.
[Brief description of the drawings]
FIG. 1 is a schematic view of the vicinity of a double facer of a corrugated board manufacturing apparatus. FIG. 2 is a schematic block diagram of an adhesion failure detection device. FIG. 3 is an explanatory diagram of the operation of the detection device of the first and second embodiments. State explanation diagram [Explanation of symbols]
1 Heating device 2 Gluing device 3 Double facer 4 Slitter scorer 5 Rotary cutter 6 Defective product removal unit 7 Cylinder 8 Travel detector 9 Subtractor 10 Adhesion failure detection circuit 11 Reference value setting device 12 Comparator 13 Control unit 14 Drive unit 15 Display vessel

Claims (1)

A speed sensor for detecting the traveling speed or traveling amount of the front liner paper and the single-sided corrugated sheet provided before the bonding step of the corrugated cardboard sheet, and calculating the difference between the detected amounts and comparing it with a reference value and a comparator , Based on the adhesion failure detection circuit that outputs the adhesion failure detection signal between the front liner paper and the single-sided corrugated cardboard sheet when the difference between the two becomes larger than the reference value, and the adhesion failure detection signal from the adhesion failure detection circuit. A cardboard sheet adhesion failure detection apparatus comprising a defective product removal unit for removing a defective adhesion portion .

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