Center seal inspection method and center seal inspection device

Abstract

To accurately inspect whether a center seal part of a vertical pillow packaging machine is normal / defective.SOLUTION: There is provided a center seal inspection method for inspecting whether a center seal part of a vertical pillow packaging machine is normal / defective, and the center seal inspection method includes: a center seal forming process for forming the center seal part to which both lengthwise sides of a resin film forming a package drawn out from a raw fabric roll are aligned; a center seal process for welding the center seal part formed in the center seal forming process; and a center seal inspection process for inspecting whether the center seal part is normal / defective. The center seal inspection process includes a light-emitting process for emitting laser light to the center seal part; a light-receiving process for receiving laser light transmitted through the center seal part; and a determination process for determining that the center seal part is defective when the quantity of light received in the light-receiving process is not within a range of values predetermined based upon the kind of the resin film and the quantity of emission of the laser light in the light-emitting process.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a center seal inspection method and a center seal inspection device for inspecting whether a center seal portion in a vertical pillow packaging machine is good or bad. [Background technology]

[0002] In a vertical pillow packaging machine, the resin film that forms the package is pulled out from a roll of raw material, the two longitudinal sides of the pulled out resin film are joined together to form a center seal, and the center seal is then welded by a center sealer. When welding the center seal with the center sealer, the resin film may become misaligned or folded, resulting in a defective center seal. Therefore, in order to inspect the quality of the center seal, a film sensor is used to detect whether the resin film is present at the position where the center sealer will weld it.

[0003] In addition, there is a device for inspecting the center seal portion of a pillow package that irradiates the center seal portion with X-rays before heating it with a center sealer to inspect whether or not foreign matter has been mixed in the center seal portion (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-2774 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, when using the above-mentioned film sensor to detect whether or not a resin film is present at the position where welding is performed by the center sealer, even if the resin film is misaligned or folded, as long as the resin film is present at the position where welding is performed by the center sealer, it will not be judged as a defective center seal, which can lead to an erroneous judgment in determining whether the center seal part is good or bad.

[0006] An object of the present invention is to provide a center seal inspection method and a center seal inspection device that can accurately inspect whether the center seal portion in a vertical pillow packaging machine is good or bad. [Means for solving the problem]

[0007] The center seal inspection method of the present invention is a center seal inspection method for inspecting the quality of a center seal portion in a vertical pillow packaging machine, and includes a center seal forming process of forming a center seal portion by joining both longitudinal sides of a resin film that forms a packaging body pulled out from an original roll, a center sealing process of welding the center seal portion formed in the center seal forming process, and a center seal inspection process of inspecting the quality of the center seal portion, and the center seal inspection process includes an emission process of emitting laser light to the center seal portion, a light receiving process of receiving laser light that has passed through the center seal portion, and a judgment process of judging the center seal portion to be defective when the amount of light received in the light receiving process is outside a predetermined value range based on the type of resin film and the amount of laser light emitted in the emission process.

[0008] In addition, in the center seal inspection method of the present invention, in the judgment process, the center seal portion is judged to be defective when the amount of light received in the light receiving process is continuously outside the predetermined value range.

[0009] In addition, in the center seal inspection method of the present invention, the center seal inspection process is carried out before the center seal process.

[0010] In addition, in the center seal inspection method of the present invention, the center seal inspection process is carried out after the center seal process.

[0011] In addition, the center seal inspection method of the present invention further includes a step of discharging the packaging body whose center seal portion is judged to be defective into a defective product discharge path if the center seal portion is judged to be defective in the judgment step.

[0012] In addition, in the center seal inspection method of the present invention, if the center seal portion is judged to be defective in the judging step, the vertical pillow packaging machine is stopped.

[0013] In addition, the center seal inspection device of the present invention is a center seal inspection device that inspects the quality / defectiveness of a center seal portion in a vertical pillow packaging machine, which comprises a center seal forming unit that forms a center seal portion by joining both longitudinal sides of a resin film that forms a packaging body pulled out from an original roll, and a center seal welding unit that welds the center seal portion formed by the center seal forming unit, and is equipped with an light emitting unit that emits laser light to the center seal portion, a light receiving unit that receives laser light that has passed through the center seal portion, and a judgment unit that judges the center seal portion to be defective when the amount of light received by the light receiving unit is outside a predetermined value range based on the type of resin film and the amount of laser light emitted by the light emitting unit.

[0014] In addition, the center seal inspection device of the present invention judges the center seal portion to be defective when the amount of light received by the light receiving portion is continuously outside the predetermined value range.

[0015] In addition, the center seal inspection device of the present invention inspects the center seal portion before welding the center seal portion at the center seal welding section.

[0016] In addition, the center seal inspection device of the present invention inspects the center seal portion after welding the center seal portion at the center seal welding section.

[0017] In addition, when the center seal inspection device of the present invention judges the center seal portion to be defective in the judgment section, it outputs an operation signal to operate an ejection mechanism which ejects the packaging body whose center seal portion has been judged to be defective into a defective product ejection path.

[0018] In addition, the center seal inspection device of the present invention outputs a stop signal to the vertical pillow packaging machine when the judging section judges the center seal portion to be defective. Effect of the Invention

[0019] According to the present invention, it is possible to accurately inspect whether the center seal portion in a vertical pillow packaging machine is good or bad. [Brief description of the drawings]

[0020] [Figure 1] 1 is a diagram showing a schematic configuration of a vertical pillow packaging machine according to an embodiment; [Diagram 2] 1 is a block diagram showing a system configuration of a center seal inspection device according to an embodiment. FIG. [Diagram 3] 10A to 10C are diagrams for explaining whether a center seal in the embodiment is good or bad. [Figure 4] 4 is a flowchart for explaining a process executed to form a package from a resin film in a vertical pillow packaging machine according to an embodiment. [Diagram 5] 5 is a flowchart for explaining a process for inspecting a center seal portion in a center seal inspection device according to an embodiment. [Figure 6] 13A and 13B are diagrams for explaining the quality of another center seal. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, a center seal inspection method and a center seal inspection device for inspecting the quality / failure of a center seal part in a vertical pillow packaging machine according to an embodiment will be described with reference to the drawings. Fig. 1 is a diagram showing a schematic configuration of a vertical pillow packaging machine according to an embodiment. As shown in Fig. 1, a vertical pillow packaging machine 2 includes an original fabric roll 10, a product filling tube 16, a former 14 which is a center seal forming section, a center seal inspection device 7, a center seal device 4 which is a center seal welding section, a film feed device 5, and an end seal device 6.

[0022] The former 14 forms a center seal portion C (area indicated by diagonal lines in the drawing) by joining both longitudinal sides of the resin film 12 from the resin film 12 (resin film 12 from which package P will be formed by the vertical pillow packaging machine 2) pulled out from the original roll 10 arranged upstream of the former 14. That is, the resin film 12 pulled out from the original roll 10 is guided to the former 14 and folded to wrap around the product filling tube 16, and both ends of the resin film 12 are joined in front of the former 14 to form the center seal portion C.

[0023] The center sealing device 4 welds the center seal portion C formed by the former 14. The resin film 12 becomes cylindrical by being center-sealed by the center sealing device 4. The film feeding device 5 is provided on the side of the product filling tube 16, and pulls the cylindrical resin film 12 down toward the end sealing device 6.

[0024] The end sealing device 6 seals and cuts predetermined portions (upper end T and lower end B of packaging body P) in the width direction of the cylindrical resin film 12. During the period from when the end sealing device 6 seals and cuts one end of the resin film 12 (upper end T of the nth packaging body P and lower end B of the (n+1)th packaging body P) to when it seals and cuts the other end of the resin film 12 (upper end T of the (n+1)th packaging body P and lower end B of the (n+2)th packaging body P), a product is charged from a hopper 18 attached to the top of the product filling tube 16 and filled into the cylindrical resin film 12 (n is a natural number).

[0025] The center seal inspection device 7 is a device for inspecting the quality of the center seal portion C, and is positioned between the former 14 and the center seal device 4. It inspects the center seal portion C after it has been formed and before it is welded.

[0026] Fig. 2 is a block diagram showing the system configuration of the center seal inspection device 7 according to this embodiment. As shown in Fig. 2, the center seal inspection device 7 is equipped with a control unit 20 that comprehensively controls each part of the center seal inspection device 7. A light emitting unit 22, a light receiving unit 24, a memory unit 26, and an input unit 28 are connected to the control unit 20.

[0027] The light-emitting unit 22 emits laser light to the center seal portion C at regular time intervals. In this embodiment, the vertical pillow packaging machine 2 packages one product per second, and the light-emitting unit 22 emits laser light at 0.5 second intervals. In other words, the light-emitting unit 22 emits laser light twice to one product (package P). The light-receiving unit 24 receives the laser light emitted by the light-emitting unit 22 and transmitted through the center seal portion C, and outputs the light reception result (amount of received light) to the control unit 20.

[0028] The memory unit 26 stores the transmittance for each type of resin film 12. It also stores a range of values ​​that is predetermined based on the transmittance for each type of resin film 12 and the amount of laser light emitted by the light-emitting unit 22. The predetermined range of values ​​is a range of values ​​of the amount of light received by the light-receiving unit 24 that is set based on the transmittance of the resin film 12 and the amount of light emitted by the light-emitting unit 22, and is a range of values ​​of the amount of light received that allows the center seal portion C to be determined as good. The input unit 28 inputs the type of resin film 12 used in the vertical pillow packaging machine 2, etc.

[0029] The control unit 20 functions as a judgment unit that judges the center seal portion C to be defective when the amount of laser light received by the light receiving unit 24 is outside the range of a predetermined value (a value stored in the memory unit 26) based on the type of resin film 12 and the amount of laser light emitted by the light emitting unit 22.

[0030] Fig. 3 is a view of the center seal inspection device 7 as seen from the former 14 side, and Fig. 3(A) is a diagram showing an example in which the center seal portion C is good, and shows a state in which the two resin films 12a, 12b (both ends in the width direction of the resin film 12) at the center seal portion C are overlapped without shifting or folding. In contrast, Fig. 3(B) is a diagram showing a seal misalignment state in which the overlapping of the two resin films 12a, 12b is misaligned, and Fig. 3(C) is a diagram showing an example in which the center seal portion C is defective, and shows a seal folding state in which the resin film 12a of the two resin films 12a, 12b is folded.

[0031] 3A, in the case of a non-defective product, the laser light L (area indicated by dots in the figure) emitted from the light-emitting unit 22 passes through each of the two resin films 12a, 12b in the center seal portion C and reaches the light-receiving unit 24. If the amount of emission of the laser light L emitted from the light-emitting unit 22 is 100 and the transmittance of the resin film 12 is 80%, the laser light L is attenuated by 20% when it passes through the first resin film 12a, so the amount of the laser light L is 100×(1−0.2)=80, and is further attenuated by 20% when it passes through the second resin film 12b, so the amount of the laser light L is 80×(1−0.2)=64. That is, the amount of emission of the laser light L emitted from the light-emitting unit 22 is 100, while the amount of the laser light L received by the light-receiving unit 24 is 64.

[0032] 3B, a portion L1 (region indicated by large dots) of the laser light L emitted from the light-emitting unit 22 passes through each of the two resin films 12a and 12b, but the other portion L2 (region indicated by small dots) of the laser light L passes through only one resin film 12b. If the amount of the laser light (part L1 of the laser light L) passing through the two resin films 12a and 12b is 70% and the amount of the laser light (other portion L2 of the laser light L) passing through one resin film 12b is 30%, then only the portion L1 of the laser light L attenuates by 100×0.7×0.2=14% when passing through the first resin film 12a, so the amount of light of the laser light L (L1+L2) is 100×(1-0.14)=86. Then, since the laser light L (L1+L2) is further attenuated by 20% when passing through the second resin film 12b, the amount of light of the laser light L (L1+L2) becomes 86×(1−0.2)=68.8. That is, for an emission amount of 100 of the laser light L emitted from the light emitting unit 22, the amount of the laser light L received by the light receiving unit 24 becomes 68.8.

[0033] 3(C), the laser light L emitted from the light-emitting unit 22 passes through one resin film 12b and reaches the light-receiving unit 24. Therefore, the laser light L does not pass through the first resin film 12a, and is attenuated by 20% when it passes through the second resin film 12b, so the amount of laser light L is 100×(1−0.2)=80. In other words, the amount of laser light L emitted from the light-emitting unit 22 is 100, while the amount of laser light L received by the light-receiving unit 24 is 80.

[0034] 3(B), when the width of the center seal portion C is, for example, 10 mm and the seal misalignment exceeds 3 mm, i.e., when a misalignment of more than 30% occurs, is deemed defective, the range of the amount of light received by the light receiving unit 24 is set to 64 to 68.8, and the control unit 20 determines the center seal portion C as defective when the range of the amount of light received by the light receiving unit 24 is other than 64 to 68.8. In this case, when a seal fold occurs as shown in FIG. 3(C), even if both the resin films 12a, 12b are folded, the amount of light received will be 80, i.e., a value greater than 68.8, and the product will be determined as defective.

[0035] When the amount of light received from light receiving unit 24 is other than 64 to 68.8 (outside the predetermined value range) consecutively (twice consecutively in this embodiment) and center seal portion C is determined to be defective, control unit 20 outputs an operation signal to vertical pillow packaging machine 2 to operate a discharge mechanism (not shown) that discharges packages P whose center seal portion C has been determined to be defective to a defective product discharge path. When vertical pillow packaging machine 2 receives the operation signal from control unit 20, it discharges packages P whose center seal portion C has been determined to be defective by center seal inspection device 7 to the defective product discharge path.

[0036] Next, a method for inspecting the quality of the center seal portion C using the vertical pillow packaging machine 2 according to this embodiment will be described. Fig. 4 is a flow chart for explaining the process performed in the vertical pillow packaging machine 2 to form the package P from the resin film 12.

[0037] First, the vertical pillow packaging machine 2 forms a center seal portion C by joining both longitudinal sides of the resin film 12 pulled out from the original roll 10 in the former 14 (step S10). Next, the vertical pillow packaging machine 2 transports the center seal portion C formed in step S10 to the center seal inspection device 7, and inspects the center seal C for quality in the center seal inspection device 7 (step S11).

[0038] 5 is a flowchart for explaining the process executed by the center seal inspection device 7 to inspect the center seal portion C. The control unit 20 outputs a control signal to the light emitting unit 22, which emits laser light L to the center seal portion C at regular time intervals (0.5 second intervals in this embodiment) (step S20). Next, the control unit 20 obtains the light receiving result (received light amount) from the light receiving unit 24, in which the light receiving unit 24 receives the laser light L that has passed through the center seal portion C (step S21).

[0039] The control unit 20 determines whether the amount of received light acquired in step S21 is outside a predetermined value range based on the type of resin film 12 and the amount of emitted laser light L in step S20 (step S22). Specifically, the control unit 20 reads the predetermined value range for the resin film 12 from the storage unit 26, and determines whether the amount of received light acquired in step S21 is outside the range of values ​​read from the storage unit 26. If the amount of received light is within the predetermined value range (step S22: No), the control unit 20 repeatedly performs the processes of steps S20 to S22.

[0040] On the other hand, if the amount of received light is outside the range of the predetermined value (step S22: Yes), the control unit 20 judges the center seal portion C as defective and judges whether or not this defective judgment result is the second consecutive defective judgment result (step S23). Specifically, the control unit 20 reads the previous judgment result temporarily stored in a buffer memory (not shown) and, if the previous judgment result was good (step S23: No), repeats the processes of steps S20 to S23. On the other hand, if the previous judgment result was defective (step S23: Yes), the control unit 20 judges the inspected center seal portion C (package P) as defective (step S24) and outputs an operation signal to the vertical pillow packaging machine 2 (step S25).

[0041] After the center seal device 7 finishes inspecting the center seal portion C, the vertical pillow packaging machine 2 welds the center seal portion C in the end seal device 6 (step S12 in FIG. 4). When the vertical pillow packaging machine 2 receives an operation signal from the control unit 20 (step S25 in FIG. 5), it discharges the package P whose center seal portion C has been determined to be defective in step S24 in FIG. 5 to a defective product discharge path.

[0042] According to the center seal inspection device and the center seal inspection method of this embodiment, the center seal C of the vertical pillow packaging machine 2 can be accurately inspected for quality / failure. Specifically, since the center seal inspection device 7 has the light emitting unit 22 and the light receiving unit 24, both seal fold and seal misalignment can be accurately detected by appropriately setting the range of the amount of light received by the light receiving unit 24. Also, according to the center seal inspection device and the center seal inspection method of this embodiment, the package P whose center seal C is determined to be defective is discharged to the defective product discharge path only when the amount of light received by the light receiving unit 24 is continuously outside the range of a predetermined value. Therefore, even if the center seal C is erroneously determined to be defective because the amount of light received by the light receiving unit 24 is reduced due to the laser light L passing through the position of the register mark, for example, when a mark such as a register mark is printed on the center seal C, it is possible to prevent the package P from being erroneously discharged to the defective product discharge path.

[0043] In the above-described embodiment, the center seal inspection device 7 is located upstream of the center seal device 4, and an example is given of the case where the center seal portion C is inspected before it is welded by the center seal device 4. However, the center seal inspection device 7 may also be located downstream of the center seal device 4, and the center seal portion C may be inspected after it is welded by the center seal device 4.

[0044] In the above embodiment, if the center seal inspection device 7 determines that the center seal C is defective, the package P with the center seal C determined to be defective is discharged to a defective product discharge path. However, once a seal break or seal misalignment occurs in the center seal C, it often continues, and in such a case, the operation of the vertical pillow packaging machine 2 may be stopped instead of discharging the package to the defective product discharge path.

[0045] In addition, in the above-mentioned embodiment, an example was given of a case where, when the center seal portion C is good, all (100%) of the laser light L emitted from the light-emitting portion 22 passes through the center seal portion C as shown in Figure 3 (A), but even if only a portion (e.g., 80%) of the laser light L emitted from the light-emitting portion 22 passes through a well-sealed center seal portion C as shown in Figure 6, by setting the range of the amount of light received by the light-receiving portion 24 to an appropriate range, it is possible to accurately determine whether the center seal portion C is good or bad.

[0046] It should be noted that the percentages in the expressions "all (100%) of the laser light L" and "part (e.g. 80%) of the laser light L" do not necessarily indicate the percentage of the physical amount of received light, but may be values ​​equivalent to the amount of received light output by the light receiving section of the sensor used in the center seal inspection device 7. For example, when a Keyence IB-10 is used as the laser sensor, the value equivalent to the amount of received light displayed on the light receiving section is shown as 0 to 100, so that value can be considered to be the percentage of the amount of received light of 0% to 100%. As another example, when the laser sensor used has a bar display, the percentage of the number of lit LEDs to the total number of LEDs can be used as the value of the amount of received light.

[0047] In the above embodiment, the light-emitting unit 22 emits laser light at regular intervals, but the light-emitting unit 22 may constantly emit laser light and the light-receiving unit 24 may receive laser light at regular intervals, or the light-emitting unit 22 and the light-receiving unit 24 may constantly emit and receive laser light. When the light-emitting unit 22 and the light-receiving unit 24 constantly emit and receive laser light, the control unit 20 judges whether the center seal portion C is good or bad based on the light-receiving results at regular intervals. [Explanation of symbols]

[0048] 2...vertical pillow inspection machine, 4...center seal device, 5...film feed device, 6...end seal device, 7...center seal inspection device, 10...raw material roll, 12, 12a, 12b...resin film, 14...former, 16...product filling tube, 18...hopper, 20...control unit, 22...light emitting unit, 24...light receiving unit, 26...memory unit, 28...input unit, C...center seal unit, L, L1, L2...laser light, P...packaging body.

Claims

1. A center seal inspection method for inspecting whether a center seal portion in a vertical pillow packaging machine is good or bad, comprising the steps of: a center seal forming step of forming a center seal portion by joining both longitudinal sides of the resin film forming the package pulled out from the original roll; a center seal process for welding the center seal portion formed in the center seal forming process; a center seal inspection process for inspecting the center seal portion for quality; Including, The center seal inspection process includes: a light emitting step of emitting a laser beam to the center seal portion; a light receiving step of receiving the laser light transmitted through the center seal portion; a determining step of determining that the center seal portion is defective when the amount of light received in the light receiving step is outside a range of values ​​that is predetermined based on the type of the resin film and the amount of light emitted by the laser light in the light emitting step; A center seal inspection method including:

2. In the determination step, 2. The center seal inspection method according to claim 1, wherein the center seal is determined to be defective when the amount of light received in the light receiving step is consecutively outside the range of the predetermined values.

3. The center seal inspection process includes:

3. The center seal inspection method according to claim 1, wherein the center seal inspection method is carried out before the center sealing step.

4. The center seal inspection process includes:

3. The center seal inspection method according to claim 1, wherein the center seal inspection method is carried out after the center sealing step.

5. The center seal inspection method according to claim 1 or claim 2, further comprising a step of discharging the packaging body whose center seal portion is judged to be defective to a defective product discharge path if the center seal portion is judged to be defective in the judgment step.

6. 3. The center seal inspection method according to claim 1, wherein, when the center seal portion is judged to be defective in the judging step, the vertical pillow packaging machine is stopped.

7. A center seal inspection device for inspecting the quality of a center seal portion in a vertical pillow packaging machine, the center seal inspection device comprising: a center seal forming section that forms a center seal portion by joining both longitudinal sides of a resin film forming a package pulled out from a raw material roll; and a center seal welding section that welds the center seal portion formed by the center seal forming section, a light emitting unit that emits a laser beam to the center seal portion; a light receiving section that receives the laser light transmitted through the center seal section; a determination unit that determines that the center seal portion is defective when the amount of light received by the light receiving unit is outside a range of values ​​that is predetermined based on the type of the resin film and the amount of light emitted by the laser light emitter; and A center seal inspection device comprising:

8. 8. The center seal inspection device according to claim 7, wherein the determining unit determines that the center seal is defective when the amount of light received by the light receiving unit is continuously outside the range of the predetermined values.

9. 9. The center seal inspection device according to claim 7, wherein the center seal is inspected before welding of the center seal at the center seal welding section.

10. 9. The center seal inspection device according to claim 7, wherein the center seal is inspected after welding of the center seal at the center seal welding section.

11. A center seal inspection device as described in claim 7 or claim 8, wherein when the judgment unit judges the center seal portion to be defective, it outputs an operation signal to activate a discharge mechanism that discharges the packaging body whose center seal portion is judged to be defective into a defective product discharge path.

12. 9. The center seal inspection device according to claim 7, wherein the determining section outputs a stop signal to the vertical pillow packaging machine when the center seal section is determined to be defective.

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