JP2009133640A - Adhesive coating inspection device of corrugated cardboard splicing margin piece - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adhesive coating inspection device of a corrugated cardboard splicing margin piece capable of easily inspecting whether the splicing margin piece is coated with an adhesive without being affected by the color or printing of a corrugated cardboard sheet and easy in constitution. <P>SOLUTION: The adhesive coating inspection device of the corrugated cardboard splicing margin piece is constituted so as to inspect whether the splicing margin piece 41 of the corrugated cardboard sheet fed along a box making line is coated with an aqueous adhesive and equipped with a transmitter 2 for transmitting a microwave in the route 5 crossing a splicing margin piece moving line, the receiver 3 arranged so as to be opposed to the transmitter so as to sandwich the moving line and receiving the microwave and a determine means for determining the presence of an aqueous adhesive layer 45 on the basis of the output value of the receiver. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an adhesive coating inspection apparatus for a corrugated board joint piece for inspecting whether or not an adhesive is applied to the joint piece in the manufacturing process of the cardboard box.

  In a general corrugated cardboard manufacturing process, a corrugator is used to continuously form a corrugated sheet by laminating a core and a liner, put a horizontal ruled line (score), and cut, and then print it on a box making line. Then, vertical ruled line (crease) insertion, cut groove (slotter) and joint piece formation, adhesive application to the joint piece, and box formation by joining are continuously performed.

  Here, the application of the adhesive to the joint piece is performed by a glue roll that rotates while being partially immersed in the adhesive accommodated in the bat, a glue gun that injects the adhesive from the nozzle, or the like. Therefore, there is a possibility that a joint piece in which the adhesive is not properly applied may be generated due to the supply of the adhesive to the bat or the glue gun being cut off or the nozzle of the glue gun being clogged. Conventionally, the inspection of whether or not the adhesive is applied to the joint piece has been performed by installing a camera on the cardboard sheet conveyance line and monitoring the monitor (see, for example, Patent Document 1). In addition, an apparatus that automatically detects the presence or absence of an adhesive by performing image processing on an image captured by a camera has been implemented. Or the inspection apparatus which detects the presence or absence of an adhesive agent by reflected light using an optical sensor is also implemented.

JP-A-10-156974

  However, since the corrugated cardboard sheet is conveyed at high speed on the production line, it is difficult to confirm the presence or absence of the adhesive without oversight by monitoring the monitor, and constantly monitoring the monitor is a heavy burden on the operator. . In addition, there is a problem that equipment and programs are expensive in an apparatus that performs image processing of imaging by a camera. Furthermore, in an inspection apparatus using image processing or an optical sensor, the adhesive may not be accurately detected due to the influence of the color of characters and designs printed on the surface of the cardboard sheet. In addition, since many general-purpose adhesives are white, in the case of a corrugated cardboard sheet with a white surface coat, the adhesive could not be detected by image processing or an optical sensor.

  Therefore, in view of the above circumstances, the present invention can easily inspect whether or not the adhesive is applied to the joint piece without being affected by the color or printing of the cardboard sheet, and An object of the present invention is to provide an adhesive coating inspection apparatus for a corrugated board joint piece with a simple configuration.

  In order to solve the above-mentioned problem, the adhesive coating inspection apparatus for corrugated board joint piece according to the present invention is "whether or not an aqueous adhesive is applied to the joint piece of the corrugated board sheet conveyed through the box making line. An adhesive coating inspection apparatus for corrugated seam strips for inspecting a transmitter, which transmits a microwave in a path intersecting with a travel line of the seam strip, and is disposed opposite to the transmitter across the travel line A receiver for receiving microwaves, and determination means for determining the presence or absence of an aqueous adhesive layer based on an output value from the receiver.

  “Water-based adhesives” include starch-based starch adhesives, or water-dispersed synthetic adhesives such as vinyl acetate resin emulsion adhesives, ethylene / vinyl acetate resin emulsion adhesives, and acrylic resin emulsion adhesives. It can be illustrated.

  The “joint strip moving line” is a virtual line in which the joint strip moves as the corrugated cardboard sheet disposed at a certain position on the transport line is transported. Here, there are many types of corrugated cardboard boxes (corresponding to the shape of the development of corrugated cardboard sheets). Generally, the boundary line between the seam piece and the side surface coincides with the major axis direction of the transport line. By doing so, the flap and the side face are not positioned on the movement line of the joint piece, and only the joint piece moves on the movement line.

  “Microwave” refers to a radio wave having a frequency of 3 GHz to 30 GHz.

  Microwaves pass through an insulator, such as cardboard, but have the property of being absorbed by water. Thereby, when the water-based adhesive is applied to the joint piece, the microwave transmitted from the transmitter is absorbed by moisture in the adhesive when passing through the joint piece. As a result, the output value from the receiver that has received the microwave is lower than when the water-based adhesive is not applied to the joint piece.

  Therefore, it is possible to determine the presence or absence of the aqueous adhesive layer on the joint piece, in other words, whether or not the aqueous adhesive is applied to the joint piece, using the output value from the receiver as a criterion. For example, by measuring the output value from the receiver and setting a threshold in advance for the sample in which the adhesive is applied to the joint piece and the sample in which the adhesive is not applied to the joint piece, If the output value from the receiver is smaller than the threshold value, it can be determined that the adhesive is applied, and if the output value is larger than the threshold value, it can be determined that the adhesive is not applied.

  It should be noted that the “determination means” for performing such determination can be configured as a program that causes a computer to function. Alternatively, the determination means may be configured by an operational amplifier circuit that compares the analog output from the receiver with the comparison target output corresponding to the threshold value.

  As described above, according to the present invention, the adhesive to the joint piece is obtained by the simple configuration of the microwave transmitter and the receiver and the simple determination that does not require a complicated process like the image processing program. Can be easily inspected. In addition, the transmission and absorption characteristics of microwaves by a substance do not depend on the color of the substance. As a result, even when printing is performed on the cardboard sheet or when surface coating treatment such as white is applied, it is possible to inspect whether or not the adhesive is applied without being affected by them. it can.

  In addition to the above configuration, the adhesive coating inspection apparatus for corrugated board joint pieces according to the present invention includes: an "upstream sensor for detecting the presence or absence of joint pieces upstream from an intersection position with the microwave of the moving line; A downstream sensor that detects the presence or absence of a splice piece on the downstream side of the crossing position of the movement line, and the determination unit detects the presence of the splice piece together with the upstream sensor and the downstream sensor. The presence or absence of the water-based adhesive layer is determined ".

  As the “upstream sensor” and the “downstream sensor”, a photoelectric sensor including a light projecting element that projects light toward a moving line and a light receiving element that receives reflected light and performs photoelectric conversion can be used. is there. For example, by setting so as not to detect light reflected far away from a predetermined distance, it is possible to detect only the presence or absence of seam pieces by eliminating the influence of a conveyor or the like that conveys cardboard sheets.

The reason why the determination means determines whether or not the water-based adhesive layer is present when both the upstream sensor and the downstream sensor detect the presence of the joint piece is as follows. . When a radio wave propagates in an insulating medium, the velocity is slower than that in the case of propagating in air. Specifically, if the speed at which the radio wave propagates in the air is c, the speed at which the radio wave propagates through the medium having the relative dielectric constant ε is approximately 1 / (ε) ^1/2 · c. Here, since the relative permittivity of the paper is 2 to 2.6, the speed of the radio wave transmitted through the cardboard is 0.6 to 0.7 times that of air. Accordingly, there is a phase difference between the microwave transmitted from the transmitter and received by the receiver without passing through the cardboard, and the microwave received by the receiver after passing through the cardboard. As a result, the reception level of the microwave at the receiver is lowered at the time when the front end of the transferred joint piece reaches the microwave path. That is, when a decrease in the microwave reception level was detected, the cause was absorption by moisture in the adhesive (the presence of an aqueous adhesive layer) and the front end of the joint piece approached the microwave path There are two possible cases: phase shift.

  Therefore, if the determination unit determines the presence or absence of the aqueous adhesive layer based on the output from the receiver only when both the upstream sensor and the downstream sensor detect the presence of the joint piece, Since the upstream sensor detects the joint piece when the front end of the piece enters the microwave path, the downstream sensor does not detect the existence of the joint piece. Even if the output level decreases, the determination means does not determine the presence or absence of the aqueous adhesive layer based on this.

  This makes it possible to apply the water-based adhesive to the joint piece without misunderstanding that the decrease in the output level due to the phase difference due to the difference in the propagation speed of the microwave is due to the presence of the water-based adhesive layer. Whether or not can be determined more accurately.

  As described above, as an effect of the present invention, it is possible to easily inspect whether or not the adhesive is applied to the joint piece without being affected by the color or printing of the cardboard sheet, and the configuration However, it is possible to provide an adhesive coating inspection apparatus for a corrugated cardboard joint piece.

  Hereinafter, an adhesive coating inspection apparatus for corrugated board joint pieces, which is the best embodiment of the present invention, will be described with reference to FIGS. Here, FIG. 1 and FIG. 2 are explanatory views for explaining the moving line and the joint piece, and FIG. 3 is a block diagram showing the configuration of the adhesive coating inspection device for the corrugated joint piece according to one embodiment of the present invention. 4 to 6 are side views showing the configuration and the inspection principle of the adhesive coating inspection apparatus for the corrugated seam piece of FIG. 3, and FIG. 7 is the adhesive application inspection apparatus for the corrugated seam piece of FIG. It is a flowchart explaining the flow of the process in.

  The corrugated board joint adhesive coating inspection apparatus 1 (hereinafter, simply referred to as “inspection apparatus 1”) of the present embodiment applies an aqueous adhesive to the joint piece 41 of the corrugated board sheet 40 conveyed through the box making line. It is an inspection device for inspecting whether or not it has been made, and is disposed so as to face the transmitter 2 that transmits a microwave on a path 5 that intersects the moving line 4 of the joint piece 41, and the transmitter 2 and the moving line 4 From the cross-position 15 of the moving line 4 and the upstream sensor 11 that detects the presence or absence of the joint piece 41 upstream of the cross-over position 15 of the receiver 3 that receives the microwave and the microwave of the moving line 4. The downstream sensor 12 that detects the presence or absence of the joint piece 41 on the downstream side, and a determination unit that determines the presence or absence of the aqueous adhesive layer 45 based on the output value from the receiver 3, Upstream sensor 11 and below And it performs determination of the presence or absence of the water-based adhesive layer 45 when the side sensor 12 has detected the presence of both joint flap piece 41.

  In addition, as shown in FIG. 3, the inspection apparatus 1 according to the present embodiment includes a computer 20 having a central processing unit 21, a main storage device 22, and an auxiliary storage device 23. A program that causes the computer 20 to function as determination means is stored. The auxiliary storage device 23 may store a threshold value that is a criterion for determination in a database in association with the type, composition, moisture content, and the like of the adhesive.

  Furthermore, the inspection apparatus 1 of this embodiment includes a warning light 8 and an alarm sound speaker 9 for notifying the occurrence of an abnormality based on the determination that the adhesive is not applied to the joint piece 41. .

  More specifically, as shown in FIG. 1, the corrugated cardboard sheet 40 on which the horizontal ruled lines 47, the vertical ruled lines 48, the cut grooves 49, and the joint strips 41 are formed according to the type of the cardboard box is Printing is performed, and the paper is conveyed on the conveyor 30 in the direction of the arrow A in the figure. At this time, an imaginary line (illustrated two-dot chain line) parallel to the conveyance direction in which the joint piece 41 moves with conveyance is the movement line 4. In addition, although the cardboard sheet 40 of the “0201 format” which is a general-purpose format is illustrated in FIG. 1, the format of the cardboard box is not limited to this.

  Then, a water-based adhesive is applied to the joint piece 41 of the corrugated cardboard sheet 40 conveyed by a glue roller (not shown). In the present embodiment, as shown in FIG. 2, the water-based adhesive is applied to the inner portions (indicated by hatching in the drawing) of the total length L1 of the joint piece 41 on the moving line 4 by the length L2 from both ends. The case where it apply | coats is illustrated.

  As shown mainly in FIG. 4, a microwave transmitter 2 is provided above the conveyor 30. A receiver 3 that receives microwaves and outputs a voltage is provided below the conveyor 30 so as to face the transmitter 2 with the conveyor 30 interposed therebetween. The transmitter 2 and the receiver 3 of this embodiment are arranged so that the microwave path 5 is substantially orthogonal to the surface of the conveyor 30 and intersects the moving line 4. In the present embodiment, the transmitter 2 that transmits a microwave having a frequency of 24.15 GHz band (24.05 to 24.25 GHz) is used. This frequency band is approved for use by specific low-power radio stations (radio stations that can be operated without a license under the Radio Law).

  Further, an upstream sensor 11 is provided upstream of the transmitter 2 and a downstream sensor 12 is provided downstream of the transmitter 2 above the conveyor 30. The upstream sensor 11 and the downstream sensor 12 of the present embodiment each have a light projecting element (not shown) that projects light toward the moving line 4 and a light receiving element (not shown) that receives reflected light and generates charges. And.

  In the present embodiment, the intervals between the upstream sensor 11 and the downstream sensor 12 and the transmitter 2 are set to be equal to D and satisfy the relationship L2 <D. This is because the upstream sensor 11 and the downstream sensor 12 both detect the presence of the joint piece 41 and transmit microwaves to the end portion of the joint piece 41 to which no adhesive is originally applied. This is to avoid the possibility of notifying the abnormality by determining that the adhesive is not applied. Further, in order for both the upstream sensor 11 and the downstream sensor 12 to detect the joint piece 41, it is necessary that D <(L1) / 2. In the present embodiment, the distance D is set to be slightly larger than L2 and considerably smaller than (L1) / 2.

  Next, the inspection principle of the inspection apparatus 1 and the flow of processing by the determination means will be described mainly with reference to FIG. 7 with reference to FIGS. When the inspection apparatus 1 starts operating, first, 0 is given to the flag F as an initial value (step S1). Next, it is confirmed whether or not the upstream sensor 11 has detected the joint piece 41. If not detected (hereinafter referred to as “OFF”) (No in step S2), the process returns to step S1. The process is repeated until it is detected.

  If the upstream sensor 11 has detected the joint piece 41 (hereinafter referred to as “ON”) (Yes in step S2), it is further confirmed whether or not the downstream sensor 12 has detected the joint piece 41. (Step S3) If it is OFF (No in Step S3), the process returns to Step S1. That is, the above processing is repeated until both the upstream sensor 11 and the downstream sensor 12 are turned on.

  Here, as shown in FIG. 4, when the front end of the joint piece 41 reaches the microwave path 5, it is caused by a phase difference between the microwave propagating in the atmosphere and the microwave propagating in the cardboard. Thus, the voltage output from the receiver 3 temporarily decreases. However, in this state, since the upstream sensor 11 is ON but the downstream sensor 12 is OFF, the process does not proceed to the next step of determining whether or not the aqueous adhesive layer 45 is present. Thereby, it is possible to distinguish between a decrease in output voltage due to the phase difference of the microwave and a decrease in output voltage due to moisture absorption by the microwave.

  When both the upstream sensor 11 and the downstream sensor 12 are turned on (Yes in step S3), the output value from the receiver 3 is compared with the threshold value (step S4). When the output value is less than or equal to the threshold value (No in step S4), it can be determined that there is moisture in the microwave path 5, that is, a normal state in which the water-based adhesive is applied to the joint piece 41. Return to S1.

  On the other hand, when the output value is larger than the threshold value (Yes in step S4), the microwave path 5 does not contain a predetermined amount or more of water, and the water-based adhesive is not applied to the joint piece 41, that is, abnormal. It is determined that

  Here, in this embodiment, the abnormality process is not performed based on the determination of abnormality once in step S4. That is, when it is determined Yes (abnormal) in step S4, 1 is added to the flag F (step S5), and the F after the addition is compared with a predetermined numerical value N (step S6). ). This numerical value N can be determined in advance based on an allowable length (or area) or the like even if no adhesive is applied. If F does not reach N (No in step S6), the process returns to step S1 and the above process is performed again. For example, in the subsequent processing, if it is determined that there is no abnormality in the application of the adhesive (No in step S4), the process returns to step S1 again, and the previous determination of abnormality is ignored. . As a result, it is possible to operate the box making line without determining that a very small amount of adhesive adhesive, local peeling of the adhesive layer, or the like that does not affect the bonding of the corrugated cardboard sheets is abnormal.

  On the other hand, when F reaches N, that is, when it is determined that there is an abnormality N times (Yes in step S6), an abnormality process is performed (step S7), and then the process ends. Abnormal processing here refers to lighting of a warning lamp, operation of an alarm sound speaker, automatic stop of a conveyance line, and the like.

  In addition, while the process which returns from step S4 to step S1 is repeated, along with conveyance of the joint piece 41 which has been the object of determining the presence or absence of the water-based adhesive layer 45, the upstream side as shown in FIG. When both the sensor 11 and the downstream sensor 12 are in the ON state, as shown in FIG. 6, when the upstream sensor 11 is OFF and the downstream sensor 12 is ON (No in step S2), the process goes to step S1 in this case as well. Return. Then, the processes in steps S1 to S3 are repeated until both the upstream sensor 11 and the downstream sensor 12 are turned on again. When both the upstream sensor 11 and the downstream sensor 12 are turned on, the same process as described above is performed. Done.

  As described above, according to the inspection apparatus 1 of the present embodiment, the adhesive application to the joint piece 41 can be performed with a simple configuration of the microwave transmitter 2 and the receiver 3 and a program that requires simple processing. Can be easily inspected. In addition, by using microwaves that do not depend on the color of the substance, even if the corrugated cardboard sheet 40 is printed or is subjected to a surface coating treatment such as white, it has an effect on them. The presence or absence of the application of the adhesive can be inspected without receiving.

  In addition, the configuration in which the presence or absence of the water-based adhesive layer 45 is determined only when both the upstream sensor 11 and the downstream sensor 12 are ON, from the receiver 3 generated due to the difference in the propagation speed of the microwave. Thus, it is possible to more accurately inspect the application of the adhesive while eliminating the influence of the decrease in the output voltage. In addition, it is possible to set to transmit a microwave from the transmitter only when both the upstream sensor 11 and the downstream sensor 12 are ON, which contributes to energy saving measures.

  The present invention has been described with reference to the preferred embodiments. However, the present invention is not limited to the above-described embodiments, and various improvements can be made without departing from the scope of the present invention as described below. And design changes are possible.

  For example, in the above embodiment, the case where the transmitter 2 is arranged above the conveyor 30 and the receiver 3 is arranged below is illustrated, but the present invention is not limited to this, and the positional relationship between the two may be reversed. .

  Moreover, although the case where the conveyance line is automatically stopped as an abnormal process has been illustrated, the present invention is not limited to this, and the adhesive can be replenished while the conveyance line is in operation. Further, it is possible to further add a configuration in which the corrugated cardboard sheet with poor adhesive application generated during that time is automatically excluded from the transport line based on the detection of the moving distance using an encoder or the like.

  Furthermore, although the case where there is a portion (length L2 portion) where the adhesive is not applied to both ends of the joint piece 41 is illustrated, the present invention is not limited to this, and the setting where the adhesive is applied over the entire length L1 of the joint piece. Even in this case, the presence or absence of application of the adhesive can be inspected.

It is explanatory drawing explaining a movement line and a joint piece. It is explanatory drawing explaining a movement line and a joint piece. It is a block diagram which shows the structure of the adhesive agent coating inspection apparatus of the corrugated board joint piece which is one Embodiment of this invention. It is a side view which shows the structure and test | inspection principle of the adhesive agent coating test | inspection apparatus of the corrugated board joint piece of FIG. It is a side view which shows the structure and test | inspection principle of the adhesive agent coating test | inspection apparatus of the corrugated board joint piece of FIG. It is a side view which shows the structure and test | inspection principle of the adhesive agent coating test | inspection apparatus of the corrugated board joint piece of FIG. It is a flowchart explaining the flow of a process in the adhesive agent coating inspection apparatus of the corrugated board joint piece of FIG.

Explanation of symbols

1 Detection device (corrugated cardboard joint adhesive application inspection device)
2 Transmitter 3 Receiver 4 Movement line 5 Microwave path 11 Upstream sensor 12 Downstream sensor 15 Crossing position 41 Joint piece 45 Water-based adhesive layer

Claims (2)

An adhesive coating inspection device for corrugated seam strips for inspecting whether or not a water-based adhesive is applied to the seam strips of corrugated cardboard sheets conveyed through a box making line,
A transmitter that emits microwaves in a path that intersects the moving line of the joint piece;
A receiver that is disposed opposite to the transmitter across the moving line and receives microwaves;
An apparatus for inspecting adhesive application of a corrugated board joint piece, comprising: a judging means for judging the presence or absence of an aqueous adhesive layer based on an output value from the receiver. An upstream sensor for detecting the presence or absence of a joint piece on the upstream side of the crossing position with the microwave of the moving line;
Further comprising a downstream sensor for detecting the presence or absence of a joint piece downstream from the intersection position of the moving line,
2. The cardboard according to claim 1, wherein the determination unit determines whether or not a water-based adhesive layer is present when both the upstream sensor and the downstream sensor detect the presence of a joint piece. Adhesive application inspection device for joint piece.

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