Film detection device for bag making and filling machines

Abstract

To provide a device capable of determining whether two overlapping portions at both side edges of a tubular film formed by making a transparent strip-shaped film into a tubular bag have been sealed by a center seal device. [Solution] In a bag making and filling machine equipped with a film supply device 10, a bag maker 20, an item supply device 30, a center seal device 60, and an end seal device 70, a film determination device 100 is located downstream of the center seal device 60 and is equipped with a lighting device 130, a first polarizing plate 110, a camera device 140, and a second polarizing plate 120, and uses the camera device 140 to capture an image of an area including at least a portion of both side edges including the overlap portion FL, and determines the overlap state of the overlap portion FL of the tubular film FT based on the image information captured through the first polarizing plate 110 and the second polarizing plate 120.

Description

[Technical Field]

[0001] The present invention relates to a film determination device for a bag making and filling machine. [Background technology]

[0002] Conventionally, it has been difficult to confirm the presence of a thin, easily deformed transparent strip-shaped film, so a technology has been disclosed for confirming the presence of the film through a polarizing filter. For example, Patent Document 1 discloses a technology in which two polarizing filters are provided as a pair, with a light-emitting element on one side of the polarizing filter and a light-receiving element on the other side of the polarizing filter. The polarization axes of the two polarizing filters are orthogonal to each other, allowing light to pass through and be received, thereby enabling the presence of a transparent plastic film located between the two filters to be confirmed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 59-51030 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the technology disclosed in the above-mentioned Patent Document 1 can only confirm the presence of film. In other words, there is a problem in that it is not possible to detect whether the overlapping films are properly sealed. Specifically, there is a problem in that the center seal device constituting the bag making and filling machine cannot determine whether the state in which the two overlapping side edges of the film formed into a cylindrical bag from a transparent strip-shaped film are sealed by applying heat and pressure, and further improvement is desired.

[0005] The present invention aims to provide a device that can determine whether the two overlapping portions on both side edges of a tubular film made by forming a transparent strip film into a tubular bag have been sealed by a center seal device. [Means for solving the problem]

[0006] In order to solve the above problems, the film determination device in the bag making and filling machine of the present invention takes the following measures. First, the invention according to claim 1 comprises a film supply device (10) that supports a film roll (R) made of a transparent strip film (F) and transports the transparent strip film (F), a bag former (20) that overlaps both side edges of the transparent strip film (F) drawn out from the film roll (R) to form a cylindrical tubular film (FT), an article supply device (30) that supplies articles (P) to the bag former (20), and a film supply device (30) that supplies the transparent strip film (F) extending from the tubular portion (FTP) of the tubular film (FT). In a form-fill-seal machine comprising a center seal device (60) that applies a center seal along the conveying direction of the tubular film (FT) to an overlapping portion (FL) of a two-ply portion (F2) where both side edge portions of the tubular film (F) are overlapped, and an end seal device (70) that applies a seal and cut to the tubular film (FT) at a position between articles (P) sequentially accommodated in the tubular portion (FTP) along a direction intersecting the conveying direction of the tubular film (FT), a lighting device (130) disposed downstream of the center seal device (60) and on one side of a direction intersecting the overlapping portion (FL) of the tubular film (FT) that has passed through the center seal device (60) and been center-sealed; a first polarizing plate (110) disposed between the lighting device (130) and the overlapping portion (FL) of the tubular film (FT); and a second polarizing plate (110) disposed downstream of the center seal device (60) and on one side of a direction intersecting the overlapping portion (FL) of the tubular film (FT) that has passed through the center seal device (60). and a second polarizing plate (120) disposed between the camera device (140) and the overlapping portion (FL) of the tubular film (FT), and the camera device (140) captures an image of an area including at least a portion of both side edges including the overlapping portion (FL), and the overlapping state of the overlapping portion (FL) of the tubular film (FT) is determined based on the image information captured through the first polarizing plate (110) and the second polarizing plate (120).

[0007] According to the invention of claim 1, the camera device (140) in the film determination device (100) captures an image of an area including at least a portion of both side edges, including the overlapping portion (FL). The overlapping state of the overlapping portion (FL) of the tubular film (FT) is determined based on the image information captured through the first polarizer (110) and the second polarizer (120). Conventionally, when a transparent film is captured by the camera device (140), the overlapping portion (FL) of the tubular film (FT) is also captured as transparent, making it impossible to determine the overlapping state. However, when the overlapping portion (FL) is captured through the first polarizer (110) and the second polarizer (120), the image information differs between the overlapping and non-overlapping portions of the film. Therefore, the overlapping state of the overlapping portion (FL) of the tubular film (FT) can be determined based on this image information. Furthermore, since the image information is captured downstream of the center seal device (60), the determination is made after center sealing, improving the accuracy of seal determination. This makes it possible to provide a device that can determine whether the two overlapping portions on both side edges of the tubular film (FT) made from a transparent strip film (F) into a tubular bag have been sealed by the center seal device (60).

[0008] Next, the invention of claim 2, which is dependent on claim 1, has a preset detection point (DP) set within the imaging range (A) photographed by the camera device (140), and based on a judgment of the imaging information, it is judged whether or not a first boundary end (FE1), among the boundary ends (FE) at the overlapping portion (FL) of the tubular film (FT), which is perpendicular to the conveying direction of the tubular film (FT) and farther from the tubular portion (FTP) of the tubular film (FT), passes on the normal position side of the detection point (DP).

[0009] According to the invention of claim 2, a preset detection point (DP) is provided within the imaging range (A) captured by the camera device (140), and it is determined whether the first boundary edge (FE1) passes the normal position side of the detection point (DP) based on the determination of the imaging information. In other words, by determining whether the overlapping portion (FL) of the tubular film (FT) is sealed to an appropriate width, it is possible to determine whether the sealing state is correct.

[0010] Next, the invention of claim 3, which is dependent on claim 1, has a predetermined detection line (DL) extending in a direction along the conveying direction of the tubular film (FT) within the imaging range (A) photographed by the camera device (140), and based on a judgment of the imaging information, it is judged whether or not a first boundary end (FE1), among the boundary ends (FE) at the overlapping portion (FL) of the tubular film (FT), which is perpendicular to the conveying direction of the tubular film (FT) and farther from the tubular portion (FTP) in the tubular film (FT), passes on the normal position side of the detection line (DL).

[0011] According to the invention of claim 3, a preset detection line (DL) is provided that extends in the direction of transport of the tubular film (FT), and based on the determination of the image information, it is determined whether the first boundary edge (FE1) passes on the normal position side of the detection line (DL). In other words, by determining whether the overlapping portion (FL) of the tubular film (FT) is sealed to the appropriate width, it is possible to determine whether the sealing state is correct.

[0012] Next, the invention of claim 4, which is dependent on claim 1, has a predetermined detection area (DA) that partitions a certain range in the direction along the conveying direction of the tubular film (FT) within the imaging range (A) photographed by the camera device (140), and based on the judgment of the imaging information, it is judged whether or not the first boundary end (FE1) of the boundary end (FE) at the overlapping portion (FL) of the tubular film (FT), which is perpendicular to the conveying direction of the tubular film (FT) and far from the tubular portion (FTP) of the tubular film (FT), passes through the detection area (DA), which is on the normal position side.

[0013] According to the invention of claim 4, a predetermined detection area (DA) is provided that defines a certain range along the conveyance direction of the tubular film (FT), and based on the determination of the image information, it is determined whether the first boundary edge (FE1) passes through the detection area (DA), which is the normal position side. In other words, by determining whether the overlapping portion (FL) of the tubular film (FT) is sealed to an appropriate width, it is possible to determine whether the sealing state is correct.

[0014] Next, the invention according to claim 5, which is dependent on claim 1, is such that the camera device (140) can distinguish and display the overlapping state of the transparent strip films (F) in different colors or shades depending on the number of overlapping sheets based on the captured image information.

[0015] According to the invention of claim 5, the difference in the number of overlapping transparent strip-shaped films F (F) becomes clear, and it is possible to determine whether the overlapping state is correct. For example, it is possible to determine whether there is a seal gap on one side of only one layer (F1), whether the seal state is too poor due to excessive overlapping of three layers (F3) or four layers (F4), wrinkles, or bag collapse.

[0016] Next, the invention of claim 6, which is dependent on any of claims 1 to 5, measures, based on a judgment of the imaging information, the amount of deviation between the first boundary end (FE1) of the overlapping portion (FL) of the tubular film (FT) that is perpendicular to the conveying direction of the tubular film (FT) and far from the tubular portion (FTP) of the tubular film (FT) and the film end (FE3) of a single portion (F1) of the transparent strip film (F) where both side edges are not overlapped and that is perpendicular to the conveying direction of the tubular film.

[0017] According to the invention of claim 6, it is possible to judge whether the overlapping state of both side edges of the transparent belt-like film (F) is normal or abnormal, and also to measure the amount of misalignment. [Effects of the Invention]

[0018] By adopting the means of each of the above-mentioned inventions, the present invention can provide an apparatus that can determine whether the two overlapping portions on both side edges of a tubular film made from a transparent strip of film have been sealed by a center seal device. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a schematic front view showing the schematic configuration of a horizontal bag making and filling machine according to the present embodiment. FIG. [Figure 2] 1A is a partially enlarged plan view of the periphery of the center seal device, and FIG. 1B is a partially enlarged front view of the periphery of the center seal device. [Figure 3] FIG. 2 is an enlarged view of the film determination device as seen from the film transport direction. [Figure 4] FIG. 4 is an enlarged view of part IV in FIG. 2(B), showing the relationship between the center seal device and the overlapping portion of the tubular film. [Figure 5] 1A is a diagram showing a normal state as determined by the film determination device displayed on the display screen, and FIG. 1B is a diagram showing an abnormal state as determined by the film determination device displayed on the display screen. [Figure 6] 10A and 10B are diagrams showing an embodiment in which different colors and shades are displayed depending on the number of overlapping transparent strip-shaped films. [Figure 7] (A) is a diagram showing the measurement of the amount of misalignment at both side edges of a transparent strip film displayed on a display screen, and (B) is a diagram showing the measurement points for the amount of misalignment at both side edges of a transparent strip film. [Figure 8] 1A is a partially enlarged front view of the periphery of the meandering adjustment unit, and FIG. 1B is a partially enlarged side view of the periphery of the meandering adjustment unit. [Figure 9] 1A is a diagram showing a normal state as determined by the film determination device displayed on the display screen, and FIG. 1B is a diagram showing an abnormal state as determined by the film determination device displayed on the display screen. [Figure 10] 1A is a diagram showing a normal state as determined by the film determination device displayed on the display screen, and FIG. 1B is a diagram showing an abnormal state as determined by the film determination device displayed on the display screen. DETAILED DESCRIPTION OF THE INVENTION

[0020] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a film determination device for a bag making and filling machine according to the present invention will be described below with reference to the drawings.

[0021] As shown in FIG. 1, a form-fill-seal machine is a device for producing a packaged product containing an item P. Specifically, a transparent strip film F is continuously (or intermittently) conveyed from a film roll R in a film supply device 10 toward a bag former 20. In the bag former 20, both side edges of the transparent strip film F drawn from the film roll R are overlapped to form a cylindrical tubular film FT. A center seal (also referred to as a vertical seal) is applied by a center seal device 60 along the conveyance direction of the item P and the tubular film FT to the overlapping portion FL of the two-ply overlapping portion F2 where both side edges of the transparent strip film F extending from the tubular portion FTP of the tubular film FT are overlapped. At predetermined intervals (sequentially) in the tubular portion FTP, an end seal (also referred to as a horizontal seal) and cut are applied by an end seal device 70 along a direction intersecting the conveyance direction of the item P and the tubular film FT at positions of the tubular film FT between the front and rear articles P contained therein. In this way, a packaged product containing the item P is obtained. The horizontal bag making and filling machine is also provided with a film determination device 100 that determines the overlapping state of the overlapping portion FL of the tubular film FT.

[0022] The transparent strip film F used for packaging is a transparent plastic film, allowing the interior of the package to be seen. The transparent strip film F is a multilayer laminate film made by bonding multiple films together, and has a "base layer" and a "sealant layer" for different functions. The base layer is the outermost layer in the package and functions as the "skeleton." The sealant layer is the innermost layer in the package and forms the inner surface of the package. The sealant layers melt when heated to a predetermined temperature while overlapping each other, and are crimped together when sandwiched in this state. When describing this embodiment, the terms "front-rear," "left-right," and "up-down" refer to the direction along the conveying direction of the tubular film FT containing the article P, "front-rear," the horizontal direction intersecting the conveying direction, and the vertical direction intersecting the conveying direction, respectively. These directions are indicated by appropriate arrows in each figure.

[0023] <Overall overview of the form-fill-seal machine> In this embodiment, the bag making and filling machine is described as an example of a horizontal bag making and filling machine using a normal pillow method, which transports the item P and the tubular film FT horizontally and forms an overlapping portion FL that extends downward in an upright position from the tubular portion FTP of the tubular film FT.

[0024] As shown in Figures 1 to 4, the horizontal bag making and filling machine is mainly composed of a film supply device 10, a bag former 20, an article supply device 30, a pair of feed rollers 40, a pair of bar heaters 50, a center seal device 60, and an end seal device 70.

[0025] The film supply device 10 is mainly composed of a shaft 12, guide rollers 14, a payout roller 16, and a film roll R. The frame of the horizontal form-fill-seal machine is configured with a shaft 12 that protrudes horizontally, and the film roll R is supported on this shaft 12. The transparent strip film F that is pulled out from the film roll R is guided sequentially by multiple guide rollers 14 toward the bag former 20. The payout roller 16 is disposed between the guide rollers 14, and conveys the transparent strip film F toward the bag former 20 while applying tension to it using the rotational driving force of a motor or the like (not shown).

[0026] The bag former 20 forms a transparent strip-shaped film F drawn from a film roll R into a tubular film FT.

[0027] The article supply device 30 is a device that supplies articles P to the bag former 20, and is, for example, a supply conveyor that supplies articles P toward the tubular film FT formed by the bag former 20 at predetermined intervals.

[0028] A pair of feed rollers 40 clamp the overlapping portion FL, where the left and right side edge portions of the tubular film FT, which is formed into a cylindrical shape, overlap each other in the left and right direction that intersects the longitudinal direction, from both sides in the left and right direction, which is perpendicular to the feed direction of the tubular film FT and the direction in which the article P is conveyed (hereinafter referred to as the conveying direction), and send the tubular film FT toward a pair of bar heaters 50 downstream in the conveying direction by means of a rotational driving force transmitted from a driving source such as a motor (not shown).

[0029] The pair of bar heaters 50 are disposed downstream in the conveyance direction from the pair of feed rollers 40, spaced apart on the left and right of the overlapping portion FL of the tubular film FT, and are preheating devices that preheat the overlapping portion FL.

[0030] The center seal device 60 is positioned downstream and close to the pair of bar heaters 50, and clamps the overlapping portion FL, where the sealant layer has been preheated by the bar heaters 50, from both the left and right sides while a pair of center rollers rotate using a rotational driving force transmitted from a driving source such as a motor (not shown), thereby crimping the overlapping portion FL (the portion where both left and right side edges are overlapped) of the tubular film FT.

[0031] The end seal device 70 applies an end seal to the overlapping portion FL of the tubular film FT in a direction intersecting the conveying direction of the folded tubular film FT, and also cuts the seal portion with a knife built into the seal body to create a packaged product.

[0032] <About the film determination device 100> The horizontal form-fill-seal machine of this embodiment is provided with a film determination device 100 that determines the overlap state of the overlap portion FL of the tubular film FT. The film determination device 100 is configured downstream of the center-seal device 60 and mainly includes an illumination device 130, a first polarizing plate 110, a camera device 140, and a second polarizing plate 120. The film determination device 100 uses the camera device 140 to capture an image of an area including at least a portion of both side edges, including the overlap portion FL, illuminated by the illumination device 130, as an imaging area A, and determines the overlap state of the overlap portion FL of the tubular film FT based on the image information captured through the first polarizing plate 110 and the second polarizing plate 120.

[0033] The lighting device 130 is disposed on one side in a direction intersecting the overlapping portion FL of the tubular film FT that has passed through the center sealing device 60 and been center-sealed. The lighting device 130 is a device that irradiates light in the left-right direction across the overlapping portion FL of the tubular film FT, and in this embodiment, a surface lighting device is used.

[0034] The camera device 140 is disposed on the other side of the overlapping portion FL of the tubular film FT that has passed through the center-sealing device 60 and been center-sealed. That is, the camera device 140 and the lighting device 130 are disposed opposite each other in a direction intersecting the overlapping portion FL of the tubular film FT. The camera device 140 photographs the overlapping portion FL through which the irradiated light has passed at intervals (receives the light that has passed through the overlapping portion) and sequentially outputs the photographed photographed data to a control unit (not shown) in the horizontal form-fill-seal machine. The photographing interval by the camera device 140 can be changed depending on the conveyance speed of the tubular film FT. The camera device 140 photographs an area A that includes at least a portion of both side edges including the overlapping portion FL illuminated by the lighting device 130. The camera device 140 photographs at set distances. In this embodiment, in order to seamlessly determine the overlap state of the overlapping portion FL of the continuously transported tubular film FT, the band-like overlapping portion FL extending in the transport direction is continuously photographed by overlapping a portion of the image capture area A at the front and rear of the transport direction. Note that camera device 140 is located downstream of center seal device 60 and only one camera device is required; multiple camera devices are required.

[0035] The first polarizing plate 110 is disposed between the lighting device 130 and the overlapping portion FL of the tubular film FT. The second polarizing plate 120 is disposed between the camera device 140 and the overlapping portion FL of the tubular film FT. The first polarizing plate 110 and the second polarizing plate 120 have a fine slit structure, and when light passes through the polarizing plate, only light in a predetermined direction is transmitted and polarized. For example, when light passes through the polarizing plate, light corresponding to vertical waves is transmitted, and light corresponding to horizontal waves is absorbed and not transmitted. Here, the polarization direction of the first polarizing plate 110 and the polarization direction of the second polarizing plate 120 are set to differ by a predetermined angle or more (e.g., 45 degrees or more). In this embodiment, the polarization direction of the first polarizing plate 110 and the polarization direction of the second polarizing plate 120 are set to differ by 90 degrees.

[0036] The film determination device 100 uses the camera device 140 to capture an image of an area including at least a portion of both side edges including the overlapping portion FL illuminated by the lighting device 130 as an imaging area A, and determines the overlapping state of the overlapping portion FL of the tubular film FT based on the image information captured through the first polarizing plate 110 and the second polarizing plate 120. The overlapping state is determined by "edge determination," "determination of the number of overlapping films," "determination of film overlap misalignment of the center seal," and "measurement of the amount of film overlap misalignment."

[0037] <Edge detection> Edge determination is performed by the film determination device 100 to determine whether the first boundary end FE1, described later, of the overlapping portion FL of the tubular film FT passes through the normal position, and is performed when the overlapping portion FL of the tubular film FT has passed through the bar heater 50 and the center sealing device 60 and is center sealed.

[0038] 3 and 4, if the overlapping portion FL extending from the cylindrical portion FTP is tilted, the film determination device 100 cannot properly determine the overlapping portion FL. For this reason, round bar-shaped film tilt prevention members 80 hanging down from the center bed are disposed on both the left and right sides of the overlapping portion FL near the downstream side of the film determination device 100. These film tilt prevention members 80 keep the overlapping portion FL extending from the cylindrical portion FTP in an upright position while the overlapping portion FL passes through the film determination device 100, thereby preventing the overlapping portion FL from being imaged in a tilted state.

[0039] The film determination device 100 uses the camera device 140 to capture an image of an area A that includes at least a portion of both side edges including the overlapping portion FL, and outputs the image information captured through the first polarizer 110 and the second polarizer 120 to a control unit (not shown) in the horizontal form-fill-seal machine. The camera device 140 captures continuous moving images when the tubular film FT is continuously transported, and captures still images when the tubular film FT is intermittently transported. The boundary end FE at the overlapping portion FL of the tubular film FT is perpendicular to the transport direction of the tubular film FT and has a first boundary end FE1 that is far from the tubular portion FTP of the tubular film FT, and a second boundary end FE2 that is closer to the tubular portion FTP.

[0040] As shown in FIG. 5, the control unit determines whether the overlapping portion F2 has passed through the detection area DA based on the captured image captured by the camera device 140, and displays the determination result. First, the captured image captured as the imaging area A is displayed on a camera image screen 154 on the display screen 152 of the display device 150. The imaging area A displayed on the camera image screen 154 is an area that includes the overlapping portion FL, the first boundary end FE1, and the second boundary end FE2 of the tubular film FT. The control unit performs a binarization process on the captured image (image processing that converts the captured image into only two colors, black and white) to extract the overlapping portion F2 of the overlapping portion FL. The binarized image is displayed on a binarized image screen 156 on the display screen 152, with the overlapping portion F2 of the overlapping portion FL displayed as a white outline.

[0041] Within the imaging area A (imaging range) captured by the camera device 140, a predetermined detection area DA is provided, which defines a certain range in the direction along the conveyance direction of the tubular film FT. The detection area DA is set below the area where the tubular film FT is sealed by the center seal device 60. The control unit extracts only the boundary line of the white-out portion of the double-layered portion F2 of the overlapping portion FL. Of the extracted boundary lines, the control unit extracts the lower line that is in the conveyance direction as the first boundary end FE1. The control unit displays an image on the result display screen 158 in which the first boundary end FE1 extracted from the white-out portion is superimposed on the detection area DA. On the result display screen 158, the control unit determines whether the first boundary end FE1 passes through the detection area DA, which is on the normal position side.

[0042] The control unit of the horizontal form-fill-seal machine displays the results of the determination of the overlap state of the overlap portion FL on the display screen 152 of the display device 150. The display screen 152 displays the details of the determination, along with the determination result, either normal (OK) or abnormal (NG). If the first boundary end FE1 passes through the detection area DA, which is the normal position side, the area where the center roller of the center seal device 60 passes through the overlap portion FL is the only area where the overlap portion FL is sealed, and the word "OK" is displayed (FIG. 5A). On the other hand, if the first boundary end FE1 does not pass through the detection area DA, which is the normal position side, the area where the center roller of the center seal device 60 passes through includes not only the two-ply portion F2 above the first boundary end FE1 but also the single-ply portion F1 below the first boundary end FE1, and the area is determined to include an unsealed portion, and the word "NG" is displayed (FIG. 5B). Here, since the detection area DA is set below the portion where the tubular film FT is sealed by the center seal device 60, by determining that the first boundary end FE1 passes through the detection area DA, it can be determined that the overlap portion FL has been sealed by the center seal device 60.

[0043] In this embodiment, the "OK" and "NG" are displayed consecutively for each captured image area A. The camera device 140 captures images of the image area A with partial overlapping at the front and rear of the conveyance direction, thereby continuously capturing the band-like overlapping portion FL extending in the conveyance direction. As a result, a portion of the detection area DA in the direction along the conveyance direction of the tubular film FT overlaps, allowing for seamless edge determination of the overlapping state of the overlapping portion FL of the continuously conveyed tubular film FT, thereby achieving seamless edge determination.

[0044] 2, an overlapping portion retracting piece 82 is disposed between the film collapse prevention member 80 and the end sealing device 70. The overlapping portion retracting piece 82 is a member that retracts the overlapping portion FL, which has been center-sealed by the center roller 60 and is extending from the tubular portion FTP in an upright position, toward the tubular portion FTP. The overlapping portion retracting piece 82 retracts the overlapping portion FL from the vicinity of the second boundary end FE2 on the base end side (root side), and overlaps the first boundary end FE1 so that it approaches the tubular portion FTP.

[0045] <Determining the number of overlapping films> The polarization direction of the first polarizer 110 and the polarization direction of the second polarizer 120 are set to differ by a predetermined angle. Therefore, the image captured by the camera device 140 differs depending on the number of overlapping transparent strip films F.

[0046] As shown in Figure 6, the control unit can determine the area of ​​the number of overlapping films based on the difference in color tone and shading of the captured image, which is caused by the difference in the number of overlapping films in the overlapping portion FL of the cylindrical film FT, based on the captured image captured by the camera device 140 in the film determination device 100. For example, the control unit detects a two-layer portion F2 from the captured image captured by the camera device 140 in the film determination device 100, and determines the overlapping states of a one-layer portion F1, a three-layer portion F3, and a four-layer portion F4 based on the difference in color tone and shading that differ from the two-layer portion F2 (F1, F3, and F4 in Figure 6). The control unit determines overlapping states other than the two-layer portion F2, and in this embodiment, the control unit has been shown as determining the overlapping states of a one-layer portion F1, a three-layer portion F3, and a four-layer portion F4, but it can also determine overlapping states of four or more layers. As a result, when the first boundary edge FE1 passes through the detection area DA, which is the normal position side, and the overlapping portion FL is determined to be a seal including a three-ply portion F3 or a four-ply portion F4, even if the area through which the center roller of the center seal device 60 passes is only the overlapping portion FL, the control unit judges it as NG and displays the word "NG" (FIG. 5B). In other words, the difference in the number of overlapping layers of the transparent strip film F (F) becomes clear, making it possible to determine whether the overlapping state is correct. For example, it is possible to determine whether there is a seal gap on one side of only the one-ply portion (F1), whether the three-ply portion (F3) or the four-ply portion (F4) is too overlapping, whether there are wrinkles or bag collapses, etc. Furthermore, the display screen 152 of the display device 150 can distinguish and display the overlapping state of the transparent strip film F by differences in color tone and shading. The display screen 152 of the display device 150 actually displays the overlapping state of the transparent strip-shaped film F in terms of different color tones and shades, but in this drawing, the different color tones and shades of the one-layer portion F1, the two-layer portion F2, the three-layer portion F3, and the four-layer portion F4 are represented by different overlapping states of diagonal lines.

[0047] <Detecting misalignment of film on center seal> The film determination device 100 uses the camera device 140 to capture an image of an area A that includes at least a portion of both side edges including the overlapping portion FL, and outputs the image information captured through the first polarizing plate 110 and the second polarizing plate 120 to a control unit (not shown) in the horizontal bag making and filling machine.

[0048] As shown in Figure 7, film overlap misalignment of the center seal is determined from the captured image captured in imaging area A. Here, rectangular registration marks M are printed at predetermined intervals (for example, one packaging length unit) on the transparent strip film F. These registration marks M are used to determine which of the two side edges of the center seal of the transparent strip film F are not overlapping. The registration mark M is placed on only one edge of both side edges in the width direction of the transparent strip film F.

[0049] The control unit is preset to determine whether the registration mark M is located on the front or rear side of both widthwise edge portions of the transparent strip film F. In this embodiment, the front side is the right side, and the rear side is the left side (see Figures 2 and 3). There are various types of registration mark M on transparent strip film F, such as films where the mark is attached from the edge of the film, or films where the mark is attached from a position a predetermined distance α away from the edge of the film. The control unit is preset to a distance of 0 to α between the registration mark M and the edge of the film. In this embodiment, an example is described in which the control unit is preset to determine whether the registration mark M is located on the front side of both widthwise edge portions of the transparent strip film F and whether the edge of the film is located a predetermined distance α outward from the registration mark M.

[0050] The control unit performs the above-mentioned "edge determination" and then determines whether there is any film overlap misalignment of the center seal. As shown in FIG. 7(A), the camera image screen 154 displays the overlapping portion FL, which is the two-ply portion F2 including the registration mark M, in the captured image captured in the imaging area A. The control unit performs the above-mentioned "edge determination," and if the first boundary end FE1 passes through the detection area DA, which is the normal position side, determines that the overlapping portion FL has been sealed by the center seal device 60, and displays the word "OK" (determination result: normal (OK)). The control unit performs the "film misalignment determination" only when the determination result of the above-mentioned "edge determination" is normal (OK), and does not perform it if the determination result is abnormal (NG).

[0051] The control unit performs binarization processing on the captured image of the single portion F1 (image processing that converts the captured image into only two colors, black and white). The binarized image extracts the single portion F1 as a white-out portion and displays it on a binarized image screen 156 on the display screen 152. The control unit extracts two boundary lines (FE1, FE3) that run along the conveying direction from the boundary lines of the white-out portion of the single portion F1. The control unit displays the captured image in which the two boundary lines extracted from the white-out portion are superimposed on the detection area DA on a result display screen 158. Based on the two boundary lines that can be identified from the extracted image and the position of the registration mark M in the captured image, the control unit determines the boundary line that is a predetermined distance α below the registration mark M as the "boundary line on the registration mark M side," and determines the other boundary line as the "boundary line without the registration mark M." Furthermore, the control unit determines which side the "boundary line of the two-sheet overlapping portion F2" and the "boundary line of the one-sheet portion F1" are on based on the vertical positional relationship between the "boundary line on the side of the registration mark M" and the "boundary line where the registration mark M is not placed." In this embodiment, the "boundary line on the side of the registration mark M" is located on the upper side, and the "boundary line where the registration mark M is not placed" is located on the lower side. Therefore, in the overlapping state of the overlapping portion FL of the tubular film FT, the control unit determines that the front edge where the registration mark M is placed is the first boundary end portion FE1 of the two-sheet overlapping portion F2, and the back edge where the registration mark M is not placed is the film end portion FE3 of the one-sheet portion F1.

[0052] In this embodiment, the registration mark M is attached to only one edge of both widthwise edges of the transparent strip film F, making it possible to determine the overlap state. On the other hand, if the registration mark M is attached to both side edges of the transparent strip film F, the image capture results will be the same when the front side is the film end FE3 of the single-sheet portion F1 and when the back side is the film end FE3 of the single-sheet portion F1, making it impossible to determine the overlap state. However, as in this embodiment, the transparent strip film F has the registration mark M attached to only one edge of both widthwise edges of the transparent strip film F, making it possible to determine the overlap state of the overlap portion FL of the tubular film FT.

[0053] <Measurement of film misalignment of center seal> After the "determination of film misalignment of the center seal" described above is performed, the amount of film misalignment is measured. As shown in FIG. 7A, the captured image captured as imaging area A is displayed on a camera image screen 154 on a display screen 152 of a display device 150. The control unit performs binarization processing (image processing that converts the captured image into only two colors, white and black) on the captured image of the single-sheet portion F1. The binarized image extracts the single-sheet portion F1 as a white-out display and displays it on a binarized image screen 156 on the display screen 152. The control unit extracts two boundary lines along the conveying direction from the boundary lines of the white-out portion of the single-sheet portion F1. The control unit displays the captured image, in which the two boundary lines extracted from the white-out portion and the detection area DA are superimposed, on a result display screen 158. FIG. 7B is an enlarged view of the area around the registration mark M on the result display screen 158 (the detection area DA is not displayed). The control unit pre-sets multiple measurement points S1-S5 to measure the length between two boundary lines (FE1, FE3) in the Y-axis direction (vertical direction) at multiple points. The control unit measures the lengths at the pre-set measurement points S1-S5. This measures the amount of misalignment between the first boundary edge FE1 and the film edge FE3 of the single portion F1 of the transparent strip film F, which is perpendicular to the conveyance direction of the tubular film FT and where both side edges do not overlap. The largest value among the measurement results at the five measurement points S1-S5 is taken as the amount of film overlap misalignment of the center seal. For example, if measurement points S1, S2, and S3 are all β mm, and measurement points S4 and S5 are all γ mm, and β > γ, the maximum misalignment amount is displayed as "Misalignment width measurement display β mm" next to the "OK" display on the display screen 152 in Figure 7(A). Although the largest value among the measurements was used as the deviation amount, the smallest value may also be used as the deviation amount, or the average value of multiple measurements may be used as the deviation amount, as appropriate.

[0054] As described above, the control unit is configured in advance to determine whether the registration mark M is on the front or rear side of both widthwise edges of the transparent strip film F. In addition to this configuration, if the registration mark M has a different color on the front and back sides, simply setting the color determination setting and the distance α from the registration mark M to the film edge eliminates the need to configure the control unit in advance to determine whether the registration mark M is on the front or rear side. The color display of the film edge on which the registration mark M is affixed allows the determination of whether the mark is on the front or rear side, and also enables the amount of misalignment to be measured. For example, by making the front side black and the back side white, this can be determined from the captured image of the registration mark M. In this case, it does not matter whether the film overlap misalignment determination or the measurement of the amount of film overlap misalignment is performed first.

[0055] <Adjusting the meandering of transparent strip film F> The meandering of the transparent strip film F is adjusted using the two pieces of information described above: "determining the film overlap misalignment of the center seal" and "measuring the amount of misalignment of the film overlap of the center seal." When the transparent strip film F meanders, a misalignment occurs in the center-sealed overlap portion FL. For this reason, a meandering adjustment device 90 is configured to eliminate the meandering of the transparent strip film F.

[0056] As shown in FIG. 8 , a meandering adjustment device 90 is disposed between the payout roller 16 and the bag former 20. The meandering adjustment device 90 mainly comprises a support frame 92, an upper roller 94, and a lower roller 96. The upper roller 94 and the lower roller 96 are supported by the support frame 92 in parallel, spaced-apart positions. A transparent strip film F is guided by the upper roller 94 and the lower roller 96. The support frame 92 in the meandering adjustment device 90 is axially supported so as to be rotatable, with the center position of the rotation axis direction of the upper roller 94 as the rotation center 98 (starting point). The meandering adjustment device 90 rotates using a driving force transmitted from a driving source such as a motor (not shown), thereby tilting the orientation of the upper roller 94 and the lower roller 96 and adjusting the meandering of the film. Meandering adjustment is performed by measuring the amount of tilt from the average value of multiple measurements of the amount of deviation measured for each image capture. For example, if it is determined that the average value has shifted 1 mm toward the front of the transparent strip film F, the meandering adjustment device 90 tilts the transparent strip film F from the rotation center 98 as the starting point so that the shift of the transparent strip film F is corrected.

[0057] The film determination device for the bag making and filling machine described above has the following advantages. (1) The camera device 140 captures an image of an area including at least a portion of both side edges, including the overlapping portion FL. The overlapping state of the overlapping portion FL of the tubular film FT is determined based on the image information captured through the first polarizer 110 and the second polarizer 120. Conventionally, when a transparent film is captured by the camera device 140, the overlapping portion FL of the tubular film FT is also captured as transparent, making it impossible to determine the overlapping state. However, when the overlapping portion FL is captured through the first polarizer 110 and the second polarizer 120, the image information differs between the overlapping and non-overlapping portions of the film. Therefore, the overlapping state of the overlapping portion FL of the tubular film FT can be determined based on the image information. Furthermore, since the image information is captured downstream of the center seal device 60, the determination is made after center sealing, improving the accuracy of the seal determination. This provides an apparatus that can determine whether the overlapping portions of two overlapping portions of both side edges of a tubular film FT, which has been made into a tubular bag from a transparent strip film F, have been sealed by the center seal device 60. (2) A predetermined detection area DA is provided, which defines a certain range along the conveyance direction of the tubular film FT, and based on the determination of the image information, it is determined whether the first boundary end FE1 passes through the detection area DA, which is the normal position side. In other words, by determining whether the overlapping portion FL of the tubular film FT is sealed to the appropriate width, it is possible to determine whether it has been sealed by the center sealing device 60. (3) Differences in the number of overlapping transparent strip films F become clear, making it possible to determine whether the overlapping is correct. For example, it is possible to determine whether the seal is missing on one side of a single-layer section F1, whether the seal is too tightly packed in a three-layer section F3 or a four-layer section F4, or whether the bag is wrinkled or collapsed. (4) The overlapping state of both edges of the transparent strip film F can be judged not only to be normal or abnormal, but also to measure the amount of misalignment. (5) In the overlapping state of the overlapping portion FL of the tubular film FT, it is possible to determine which of the edge with the registration mark M and the edge without the registration mark M is the front side and which of the edge with the registration mark M and the edge without the registration mark M is the first boundary end FE1 and which of the edge with the registration mark M and the edge without the registration mark M is the film end FE3. (6) Using the two pieces of information, "determining the film misalignment of the center seal" and "measuring the amount of misalignment of the film misalignment of the center seal," the meandering of the transparent strip film F can be adjusted to restore the overlapping state of the overlapping part FL of the tubular film FT to its normal state. (7) It is expected that the shape of the packaged product will be distorted from the desired shape by the amount of misalignment of the film misalignment, but by applying a numerical judgment to the judgment result from the detection area DA to determine the amount of misalignment, it is possible to bring the packaged product closer to the desired shape.

[0058] <Example of change> Although the present embodiment has been described above, the film determination device in the bag making and filling machine of the present disclosure is not limited to the above embodiment, and can be embodied in various other forms. (1) In the above example, the film determination device 100 is disposed in a normal pillow-type horizontal form-fill-seal machine in which the overlapping portion FL is formed on the underside of the tubular film FT. However, the horizontal form-fill-seal machine may also be a back-seal type horizontal pillow packaging machine in which the overlapping portion FL is formed on the upper side of the tubular film FT, or a horizontal three-sided seal packaging machine in which the overlapping portion FL is formed on the side of the tubular film FT. The film determination device 100 may also be disposed in a vertical form-fill-seal machine to determine the overlapping portion FL of the tubular film FT formed by overlapping the left and right edge portions of the transparent strip film F. (2) In the embodiment shown, the film collapse prevention member 80 is located downstream of the lighting device 130, but it may be located both upstream and downstream, or only upstream. Also, a portion of the film collapse prevention member 80 may overlap the lighting device 130. (3) The overlapping portion FL of the tubular film FT is heated by the bar heater 50 and pressed by a pair of center rollers in the center seal device 60, but a method in which a pair of center rollers press the overlapping portion FL while applying heat thereto is also possible. (4) The control unit of the horizontal form-fill-seal machine determines the number of overlapping bags, but the number of overlapping bags may be determined by a separate control unit. (5) Although the imaging areas A are overlapped in the above embodiment, any desired area may be inspected without overlapping. (6) In the present embodiment, a predetermined detection area DA is provided within the imaging area A (imaging range) that defines a certain range along the conveyance direction of the tubular film FT, and a determination is made as to whether the first boundary end FE1 passes through the detection area DA, which is the normal position side. Here, as shown in FIG. 9 , a predetermined detection point DP may be provided within the imaging area A (imaging range) captured by the camera device 140, and a determination may be made as to whether the first boundary end FE1 passes closer to the normal position than the detection point DP based on the imaging information from the camera device 140. Alternatively, as shown in FIG. 10 , a predetermined detection line DL extending along the conveyance direction of the tubular film FT may be provided within the imaging area A (imaging range) captured by the camera device 140, and a determination may be made as to whether the first boundary end FE1 passes closer to the normal position than the detection line DL based on the imaging information from the camera device 140. (7) The results displayed on the display device 150 may be just the details of the determination or just the pass / fail result of the determination. (8) The result of the judgment may be notified by sound or the like instead of just by display. (9) The camera device 140 and the second polarizing plate 120 are separate, but they may be integrated. (10) Although the illumination device 130 and the first polarizing plate 110 are separate, they may be integrated. (11) The distance between the lighting device 130 and the first polarizing plate 110 can be set to various distances as long as the difference in the number of overlapping films can be determined, but it is desirable to be able to determine a clear difference (difference in color tone, difference in shading). (12) The amount of misalignment of the center seal may be determined not only by the smallest value but also by various other definitions such as the largest value or the average value of multiple measurements. (13) In the method for measuring the amount of misalignment of the center seal, either of the following may be performed first: 1) measuring the amount of misalignment first, or 2) identifying which edge is at the bottom. (14) Although the meandering adjustment device 90 has been described as moving to adjust the meandering as a whole device, the meandering adjustment may be performed by driving the position of the meandering adjustment device 90, or the meandering adjustment may be performed by driving the position of one or both of the two rollers, the upper roller 94 and the lower roller 96, of the meandering adjustment device 90. (15) The rotation center (starting point) for driving the meandering adjustment device 90 is the vertical center from the film transport direction and the center position in the direction of the rotation axis of the upper roller 94, but the rotation center may be set at another position as long as it can be driven from a starting point based on a clear standard. (16) In meandering adjustment, the average value of multiple measurement results was used to determine whether there was a deviation. However, it is also possible to determine whether to adjust the deviation based on various results, such as not adjusting the deviation if the same value of ±0.5 mm occurs a specified number of times in succession. (17) The control unit acquires positional information such as that of the conveyor installed in the horizontal form-fill-seal machine, the conveyor connected downstream thereof, and the encoder pulse attached to the film conveying motor in the horizontal form-fill-seal machine, and when it determines that the overlapping portion FL of the tubular film FT is poorly sealed, it may link this information to the positional information and, when a defectively packaged product is discharged from the horizontal form-fill-seal machine, activate a reject device (not shown) to discharge the product outside the system, notify the display device 150 of the horizontal form-fill-seal machine, or stop the operation of the packaging machine, or take other measures. (18) In this embodiment, the control unit performs an "edge determination" and then performs "determination of film misalignment of the center seal" after the determination result is determined to be normal (OK). However, various applications are possible, such as "edge determination" and "determination of film misalignment of the center seal" being performed simultaneously, or "determination of film misalignment of the center seal" being performed first. [Explanation of symbols]

[0059] 10: Film supply device 20: Bag making machine 30: Article supply device 60: Center seal device 70: End seal device 100: Film determination device 110: First polarizing plate 120: Second polarizing plate 130: Illumination device 140: Camera device A: Imaging range DA: Detection area DP: Detection point DL: Detection line F: Transparent strip film FT: Cylindrical film FTP: Cylindrical part FL: Overlapping part FE1: First boundary edge FE3: Film edge R: Film roll P: Article

Claims

1. a film supply device that supports a film roll of a transparent strip film and transports the transparent strip film; a bag former that overlaps both side edges of the transparent strip film drawn out from the film roll to form a tubular film; an article supply device that supplies articles to the bag making machine; a center seal device that applies a center seal to an overlapping portion of a two-ply portion where both side edge portions of the transparent strip film extending from the tubular portion of the tubular film are overlapped along a conveyance direction of the tubular film; an end sealing device that seals and cuts the tubular film at positions between the articles sequentially accommodated in the tubular section along a direction intersecting the conveying direction of the tubular film, downstream of the center seal device, a lighting device disposed on one side of the overlapping portion of the tubular film that has passed through the center sealing device and been center-sealed in a direction intersecting the overlapping portion; a first polarizing plate disposed between the illumination device and the overlapping portion of the tubular film; a camera device disposed on the other side of the overlapping portion of the tubular film that has passed through the center sealing device and been center-sealed in the direction intersecting the overlapping portion; a second polarizing plate disposed between the camera device and the overlapping portion of the tubular film; A film determination device in a bag making and filling machine that uses the camera device to capture an image of an area including at least a portion of both side edges including the overlapping portion, and determines the overlapping state of the overlapping portion of the tubular film based on the image information captured through the first polarizing plate and the second polarizing plate.

2. a preset detection point is provided within an imaging range photographed by the camera device, A film determination device for a bag making and filling machine as described in claim 1, which determines, based on the determination of the imaging information, whether a first boundary end portion of the overlapping portion of the tubular film that is perpendicular to the conveying direction of the tubular film and far from the tubular portion of the tubular film passes on the normal position side of the detection point.

3. a predetermined detection line extending in a direction along the transport direction of the tubular film is provided within an imaging range captured by the camera device, A film determination device for a bag making and filling machine as described in claim 1, which determines, based on the determination of the imaging information, whether a first boundary end portion of the overlapping portion of the tubular film that is perpendicular to the conveying direction of the tubular film and far from the tubular portion of the tubular film passes on the normal position side of the detection line.

4. a predetermined detection area is provided within an image capturing range captured by the camera device, the predetermined detection area being a certain range defined in a direction along the transport direction of the tubular film; A film determination device for a bag making and filling machine as described in claim 1, which determines, based on the determination of the image information, whether a first boundary end portion of the overlapping portion of the tubular film that is perpendicular to the conveying direction of the tubular film and far from the tubular portion of the tubular film is passing through the detection area, which is the normal position side.

5. The film determination device for a bag making and filling machine as described in claim 1, wherein the camera device is capable of identifying and displaying the overlapping state of the transparent strip film using different colors or shades depending on the number of overlapping sheets based on the captured image information.

6. Based on the determination of the imaging information, a first boundary end portion of the overlapping portion of the tubular film is determined to be perpendicular to the conveying direction of the tubular film and far from the tubular portion of the tubular film; A film determination device for a bag making and filling machine described in any one of claims 1 to 5, which measures the amount of deviation between the end of a single piece of transparent strip film and the film in a direction perpendicular to the conveying direction of the tubular film where both side edges of the transparent strip film do not overlap.

Images