Horizontal bag-making, filling, and packaging machine

Abstract

The present invention provides a horizontal bag-making, filling, and packaging machine that reduces deviations in the cutting position when cutting the sealed portion. [Solution] The horizontal bag-making, filling, and packaging machine comprises a tube-making device that overlaps both ends of a strip-shaped packaging material in the width direction to form a cylindrical shape, a gripping and conveying device positioned downstream of the tube-making device that grips and conveys the strip-shaped packaging material, a center sealing device positioned downstream of the tube-making device that seals the overlapped ends of the strip-shaped packaging material, an end sealing device positioned downstream of the center sealing device that seals both sides of the bag containing the product from the strip-shaped packaging material formed into a cylindrical shape by the center sealing device, a cutting device that cuts the sealed portion, a sensor that detects a positioning mark, and a control device that cuts the sealed portion when the strip-shaped packaging material has been conveyed a predetermined amount from the detection position where the positioning mark is detected, wherein the sensor is positioned downstream of the tube-making device in the conveying direction and upstream of the end sealing device.

Description

Technical Field

[0001] The present invention relates to a horizontal bag-making and filling packaging machine.

Background Art

[0002] Conventionally, a horizontal bag-making and filling packaging machine has a center seal device that seals both ends of an overlapped strip-shaped film, an end seal device that seals both ends in the conveyance direction of the strip-shaped film formed into a cylindrical shape by the center seal device, and a cutting device that cuts the seal portion of the strip-shaped film sealed by the end seal device.

[0003] On the strip-shaped film used in a horizontal bag-making and filling packaging machine, positioning marks are formed at predetermined intervals in the conveyance direction. The horizontal bag-making and filling packaging machine includes a sensor that detects the positioning marks of the strip-shaped film (see, for example, Patent Documents 1 and 2). The horizontal bag-making and filling packaging machine operates the cutting device at the timing when the strip-shaped film is conveyed a predetermined feed amount from the detection position where the positioning marks are detected. Thereby, the horizontal bag-making and filling packaging machine can cut the seal portion.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] The positioning marks formed on the strip-shaped film may be arranged at slightly shifted positions due to printing errors or the expansion and contraction of the strip-shaped film due to the external environment. In addition, the intervals at which the positioning marks are formed may be different between the vicinity of the outer periphery and the vicinity of the center of the film roll in which the strip-shaped film is formed in a roll shape.

[0006] However, in the configurations of the above-mentioned Patent Documents 1 and 2, the detection position for detecting the positioning marks is set so that the strip of film is closer to the film roll than the former (tube-making machine), resulting in a large feed amount from the detection position to the cutting position where the seal portion is cut. A large feed amount means that the number of positioning marks included in that range also increases, so there is a possibility that the misalignment of the positioning marks will be cumulatively added up. As a result, there is a problem that the cutting position where the end seal portion is cut by the cutting device is shifted from the position where it should be cut.

[0007] Furthermore, if the cutting position deviates from the intended cutting position, the product becomes defective, requiring an inspector to check the product. In addition, the adjustment mechanism that adjusts the feed amount from the detection position must be manually operated by the worker, resulting in a heavy workload. Therefore, even if the horizontal bag-making, filling, and packaging machine is automated, there is a challenge in that many adjustment tasks must be performed manually. Moreover, at the position of the tube-making machine and downstream of the tube-making machine, there are parts where the strip film is bent to form a tube, which presents a challenge in accurately detecting the positioning marks.

[0008] The present invention was made to solve the above problems, and its objective is to provide a horizontal bag-making, filling, and packaging machine that can reduce deviations in the cutting position when cutting the seal portion. [Means for solving the problem]

[0009] To solve the above problems, the present invention provides a bag-making, filling, and packaging machine for filling bags formed from a strip-shaped packaging material with a product, comprising: a tube-making device that forms a tube shape by overlapping both ends of the strip-shaped packaging material in the width direction perpendicular to the conveying direction, which is being conveyed in the conveying direction; a gripping and conveying device positioned downstream of the tube-making device in the conveying direction, which grips both overlapping ends of the strip-shaped packaging material and conveys it in the conveying direction; a center-sealing device positioned downstream of the tube-making device in the conveying direction, which seals both sides of the bag containing the product from the strip-shaped packaging material formed by the center-sealing device; and a conveying device positioned downstream of the center-sealing device in the conveying direction The device comprises an end sealing device positioned downstream of the conveying direction for sealing both ends of the strip-shaped packaging material in the conveying direction, a cutting device for cutting the sealed portion of the strip-shaped packaging material sealed by the end sealing device, a sensor for detecting positioning marks formed on the strip-shaped packaging material at predetermined intervals in the conveying direction, and a control device that operates the cutting device to cut the sealed portion when the strip-shaped packaging material has been conveyed by a predetermined amount from the detection position where the sensor detects the positioning marks, wherein the sensor is positioned downstream of the cylinder maker in the conveying direction and upstream of the end sealing device in the conveying direction. [Effects of the Invention]

[0010] According to the present invention, a horizontal bag-making, filling, and packaging machine can be obtained that reduces deviation in the cutting position when cutting the sealed portion. [Brief explanation of the drawing]

[0011] [Figure 1] This is a side view of a horizontal bag-making, filling, and packaging machine. [Figure 2] This is a plan view of a horizontal bag-making, filling, and packaging machine. [Figure 3] This is a perspective view of the cylinder forming machine and positioning mark detector, seen from the downstream side. [Figure 4] This is a plan view of a strip-shaped film. [Figure 5] This is a perspective view of the positioning mark detector from the upstream side. [Figure 6] Figure 5 is a cross-sectional view of the main part of the positioning mark detector, cut along the line VI-VI. [Figure 7] This is a side view of the positioning mark detector. [Figure 8] This is a cross-sectional view of the main part of a modified positioning mark detector. [Modes for carrying out the invention]

[0012] [Overall configuration of horizontal bag-making, filling, and packaging machine 10] Hereinafter, a horizontal bag-making, filling, and packaging machine 10 according to an embodiment of the present invention will be described with reference to the drawings. Note that the embodiments of the present invention described below are merely examples of how the present invention can be implemented, and do not limit the scope of the present invention to the scope described in the embodiments. Therefore, the present invention can be implemented by making various modifications to the embodiments.

[0013] Figure 1 is a side view of the horizontal bag-making, filling, and packaging machine 10. Figure 2 is a top view of the horizontal bag-making, filling, and packaging machine 10. The horizontal bag-making, filling, and packaging machine 10 (bag-making, filling, and packaging machine) is a device that packages products P supplied from a supply device (not shown) one by one. As shown in Figures 1 and 2, the horizontal bag-making, filling, and packaging machine 10 mainly comprises a supply conveyor 11, a packaging material feeding device 20, a cylinder maker 29, a clamping and conveying device 30, a center sealing device 40, an end sealing device 50, a cutting device 55, a positioning mark detector 60, and a control device 70.

[0014] The supply conveyor 11 supplies the products P, which are supplied sequentially from a supply device (not shown), to the cylinder forming machine 29. As shown in Figure 1, the supply conveyor 11 consists of a drive sprocket 14, a driven sprocket 15, an endless annular conveying chain 16 stretched between the drive sprocket 14 and the driven sprocket 15, and a drive motor 17 that drives the drive sprocket 14.

[0015] In addition, a plurality of pushers 18 are provided on the conveying chain 16. The plurality of pushers 18 are arranged at a predetermined interval in the conveying direction of the product P. The product P supplied from the supply device enters between two adjacent pushers 18. Then, the pusher 18 abuts against the rear end of the product P and pushes the product P.

[0016] The packaging material feeding device 20 feeds the strip film Fw (strip packaging material) toward the sandwiching and conveying device 30. As shown in FIGS. 1 and 2, the packaging material feeding device 20 includes a holder unit 21 that holds a film roll Fr (packaging material roll) in which the strip film Fw is wound around a core and formed into a roll shape, a driving roller 22, a driven roller 23, a feeding motor 24, and guide rollers 25a and 25b.

[0017] The strip film Fw is a strip packaging material that is a material for a bag for packaging the product. The strip film Fw is a film-like member that can be welded by applying heat, and examples thereof include polyethylene (PE), polyethylene terephthalate (PET), biaxially stretched polypropylene (OPP), aluminum-lined paper, aluminum vapor-deposited paper, and the like. The product refers to, for example, foods such as cookies and dorayaki. However, specific examples of the product are not limited to these and include all items packaged in the bag Bp and shipped.

[0018] The driving roller 22 and the driven roller 23 rotate while sandwiching the strip film Fw. The driving roller 22 rotates when the driving force of the feeding motor 24 is transmitted thereto. Thereby, the driving roller 22 and the driven roller 23 feed out the strip film Fw wound around the holder unit 21 toward the cylinder forming device 29. The guide rollers 25a and 25b are arranged along the conveying path of the strip film Fw from the holder unit 21 through the driving roller 22 and the driven roller 23 to the cylinder forming device 29, and apply tension to the fed-out strip film Fw.

[0019] The tube maker 29 forms the strip-shaped film Fw, which is fed by the packaging material feeding device 20, into a cylindrical shape, and also serves as an entrance for the product P supplied from the supply conveyor 11 to enter the cylindrical strip-shaped film Fw. The tube maker 29 is positioned on the transport path of the strip-shaped film Fw from the packaging material feeding device 20 to the center sealing device 40. The tube maker 29 is also positioned facing the downstream end of the supply conveyor 11 in the transport direction.

[0020] As the strip-shaped film Fw, fed by the packaging material feeding device 20, moves along the cylinder forming device 29, both ends in the width direction perpendicular to the conveying direction are overlapped at the bottom, thereby forming a cylindrical shape.

[0021] As shown in Figure 3, the cylinder maker 29 comprises a pair of side walls 29a and 29b and a pair of bottom walls 29c and 29d. The pair of side walls 29a and 29b and the pair of bottom walls 29c and 29d are fixed to the frame of the horizontal bag-making, filling, and packaging machine 10 via support members (not shown).

[0022] A pair of side walls 29a and 29b are positioned spaced apart in the width direction. Furthermore, the pair of side walls 29a and 29b extend in the conveying direction. A pair of bottom walls 29c and 29d are located below the pair of side walls 29a and 29b. A slit 29e is formed between the bottom walls 29c and 29d, extending in the conveying direction through the center in the width direction. The bottom walls 29c and 29d are positioned below the space through which the product P passes.

[0023] The pair of side walls 29a and 29b each have inclined surfaces 29f and 29g at their lower ends on the upstream side in the conveying direction. The inclined surfaces 29f and 29g are surfaces that incline upward as they move towards the upstream side in the conveying direction. The strip-shaped film Fw, which is conveyed diagonally downward from the guide roller 25b, has its central part in the width direction come into contact with the inclined surfaces 29f and 29g of the side walls 29a and 29b, and the conveying direction is switched to the horizontal direction.

[0024] On the other hand, both sides of the strip-shaped film Fw in the width direction extend downward along the inner surfaces of the side walls 29a and 29b and are located outside the cylinder maker 29 through the inclined surfaces 29f and 29g. When the strip-shaped film Fw is conveyed in the conveying direction from this state, both sides of the strip-shaped film Fw in the width direction are drawn into the inside of the cylinder maker 29 by the side walls 29a and 29b and the bottom walls 29c and 29d. The strip-shaped film Fw is then formed into a cylinder along the inner wall surfaces of the side walls 29a and 29b and the bottom walls 29c and 29d, and both ends in the width direction are overlapped and protrude downward from the slit 29e.

[0025] The product P supplied from the supply conveyor 11 passes through the inside of the cylinder maker 29 in the conveying direction, between a pair of side walls 29a and 29b and above a pair of bottom walls 29c and 29d. As the product P passes through the cylinder maker 29, it enters the inside of a cylindrical strip film Fw.

[0026] The clamping and conveying device 30 clamps the overlapping ends T of the strip-shaped film Fw formed into a cylindrical shape by the cylinder maker 29 and conveys it in the conveying direction. The clamping and conveying device 30 is located downstream of the cylinder maker 29 in the conveying direction. The clamping and conveying device 30 is also located below the strip-shaped film Fw and product P that have passed through the cylinder maker 29. The clamping and conveying device 30 mainly comprises a support plate 31, a pair of film pulling rollers 32 and 33, and a pulling motor 34.

[0027] The support plate 31 is connected to the downstream side of the cylinder forming machine 29 in the conveying direction. The product P enclosed in the tubular strip film Fw is supported on the upper surface of the support plate 31. In Figure 3, a portion of the support plate 31 is shown cut out, but in reality, in the conveying direction, the upstream end of the support plate 31 extends to the vicinity of the downstream end of the cylinder forming machine 29. The support plate 31 also extends to the position of the center seal device 40 in the conveying direction. Furthermore, the support plate 31 is provided with a slit 35 in the center in the width direction that extends along the conveying direction of the strip film Fw. The slit 35 communicates with the slit 29e of the cylinder forming machine 29. Therefore, the overlapping ends T of the strip film Fw formed in the cylinder forming machine 29 protrude downward from the support plate 31 through the slit 35.

[0028] Furthermore, within the horizontal direction, the direction in which the strip-shaped film Fw is conveyed along the support plate 31 is defined as the "conveying direction," and the direction perpendicular to the conveying direction is defined as the "width direction." In addition, the direction perpendicular to both the conveying direction and the width direction is defined as the "up and down direction." Moreover, within the up and down direction, the side of the support plate 31 towards the product P is defined as "upward," and the side towards the clamping and conveying device 30 is defined as "downward."

[0029] A pair of film pulling rollers 32 and 33 are positioned below the support plate 31. The pair of film pulling rollers 32 and 33 grip the overlapping ends T of the strip-shaped film Fw protruding through the slit 35. In addition, the film pulling rollers 32 and 33 have irregularities formed on their outer surfaces to securely grip the ends of the strip-shaped film Fw. The film pulling rollers 32 and 33 rotate when the driving force of the pulling motor 34 is transmitted to them. As a result, the cylindrical strip-shaped film Fw is conveyed in the conveying direction toward the center sealing device 40.

[0030] The center sealing device 40 seals both ends in the width direction of the strip-shaped film Fw that is overlapped in the cylinder-making device 29. The center sealing device 40 is located downstream in the conveying direction from the cylinder-making device 29 and the clamping and conveying device 30. Furthermore, the center sealing device 40 is located below the strip-shaped film Fw and the product P (in other words, the support plate 31).

[0031] The center seal device 40 mainly comprises a pair of heater bars 41 and 42, a pair of crimping rollers 43 and 44, a pair of weight rollers 45 and 46, and a weight motor 47.

[0032] The pair of heater bars 41 and 42 are positioned downstream from the cylinder-making machine 29 in the conveying direction, on the underside of the support plate 31. The pair of heater bars 41 and 42 are positioned opposite each other, sandwiching the overlapping ends T of the cylindrical strip-shaped film Fw that protrude through the slit 35. The pair of heater bars 41 and 42 heat the overlapping ends T of the cylindrical strip-shaped film Fw that protrude through the slit 35. As a result, the overlapping ends T of the cylindrical strip-shaped film Fw become molten.

[0033] The pair of crimping rollers 43 and 44 are positioned downstream of the pair of heater bars 41 and 42 in the conveying direction, and on the lower surface side of the support plate 31. The pair of crimping rollers 43 and 44 also clamp and press the overlapping ends T of the cylindrical strip film Fw protruding through the slit 35, thereby sealing (welding) the molten overlapping ends T.

[0034] The pair of basting rollers 45 and 46 are positioned downstream of the pair of crimping rollers 43 and 44 in the conveying direction, and on the lower side of the support plate 31. The pair of basting rollers 45 and 46 also grip the overlapping ends T of the cylindrical strip-shaped film Fw that protrude through the slit 35. Furthermore, multiple circumferential grooves extending in the circumferential direction are formed on the outer circumferential surfaces of the pair of basting rollers 45 and 46. The basting roller 45 rotates when the driving force of the basting motor 47 is transmitted to it. This applies basting to the ends T that are sealed by the pair of crimping rollers 43 and 44.

[0035] The overlapping ends T of the strip-shaped film Fw protruding through the slit 35 protrude downward when held between the pair of weight rollers 45 and 46. Before reaching the end sealing device 50, the ends T are pushed down towards the bottom side of the tubularly formed strip-shaped film Fw by the tilting plate 49.

[0036] The tilting plate 49 is positioned downstream of the weight rollers 45 and 46 in the conveying direction, and upstream of the end sealing device 50 in the conveying direction. The tilting plate 49 is also positioned on the lower surface of the support plate 31. Furthermore, the tilting plate 49 protrudes diagonally downward from one side of the slit 35 to the other side. The tilting plate 49 then contacts the end T of the cylindrical strip film Fw sealed by the center sealing device 40, tilting the end T toward the bottom surface of the cylindrical strip film Fw.

[0037] The end sealing device 50 is located downstream in the conveying direction from the cylinder forming device 29, the clamping and conveying device 30, and the center sealing device 40. The end sealing device 50 seals both sides in the conveying direction of the bag Bp containing the product P, which is part of the tubular strip film Fw sealed by the center sealing device 40.

[0038] [Configuration of the end seal device 50] The end sealing device 50 seals the tubular strip film Fw, which has been sealed by the center sealing device 40, on both sides of the product P in the conveying direction. In this way, the end sealing device 50 forms a bag Bp containing the product P. The end sealing device 50 mainly comprises a pair of sealing blocks 51 and 52 and a contact / separation motor 53.

[0039] A pair of seal blocks 51 and 52 are positioned vertically, sandwiching a tubularly formed strip of film Fw. The surfaces of the pair of seal blocks 51 and 52 facing the strip of film Fw are heated by a heater (not shown). The pair of seal blocks 51 and 52 move toward and toward each other by the driving force transmitted by the separation motor 53. The end sealing device 50 brings the pair of seal blocks 51 and 52 into contact between adjacent products P. As a result, both sides of the bag Bp containing the product P, which is made of the tubularly formed strip of film Fw by the center sealing device 40, are sandwiched between the seal blocks 51 and 52 and sealed (welded).

[0040] [Configuration of the cutting device 55] The cutting device 55 is fixed to the seal block 51. The cutting device 55 also includes, for example, a cutter 56 (see Figure 2) and a drive unit (not shown).

[0041] The cutter 56 slides between a separation position and a cutting position. The blade of the cutter 56 faces downward and extends in the width direction of the strip-shaped film Fw. The separation position is the position where the blade of the cutter 56 is retracted into a groove that penetrates the seal block 51 vertically, and the blade of the cutter 56 is separated upward from the strip-shaped film Fw. The cutting position is the position where the blade of the cutter 56, which protrudes from the lower surface of the seal block 51, penetrates and cuts the strip-shaped film Fw. The cutter 56 slides between the separation position and the cutting position by a driving force transmitted from the drive unit. As a result, the cutting device 55 cuts the sealed portion of the strip-shaped film Fw sealed by the end sealing device 50 (i.e., the boundary portion of the adjacent bag Bp).

[0042] [Configuration of positioning mark M] As shown in Figure 4, positioning marks M are printed on both side edges of the strip-shaped film Fw at predetermined intervals D in the transport direction. The positioning marks M are also called register marks. The predetermined interval D of the positioning marks M on the strip-shaped film Fw is set, for example, to match the cut dimensions of the cutting device 55. The positioning mark detector 60 detects the positioning marks M formed on the strip-shaped film Fw.

[0043] [Configuration of the positioning mark detector 60] As shown in Figures 5 to 7, the positioning mark detector 60 is located downstream of the cylinder maker 29 in the conveying direction and upstream of the end seal device 50 in the conveying direction. More preferably, the positioning mark detector 60 is located downstream of the cylinder maker 29 in the conveying direction and upstream of the center seal device 40 in the conveying direction. Even more preferably (in this embodiment), the positioning mark detector 60 is located downstream of the cylinder maker 29 in the conveying direction and upstream of the clamping conveying device 30 in the conveying direction. More specifically, the detection position DP (see Figure 7) where the positioning mark detector 60 detects the positioning mark M is located upstream of the film pulling rollers 32 and 33 of the clamping conveying device 30 in the conveying direction. Furthermore, the positioning mark detector 60 is located below the support plate 31.

[0044] The positioning mark detector 60 comprises an optical sensor 61, a sensor holder 62, a support block 63, and a reflector 65. The detection position DP is the position of the optical sensor 61 in the transport direction. The detection position DP is also a position below the support plate 31 in the vertical direction.

[0045] The reflector 65 is formed in a thin plate shape and extends in a direction perpendicular to the width direction. The reflector 65 is positioned below the slit 35 of the support plate 31. More specifically, the reflector 65 is positioned so that its width direction is closer to the side away from the light sensor 61 and sensor holder 62 (the side where one surface 65a of the reflector 65 is located) than the center line CL of the slit 35 (see Figure 6). As a result, both ends T of the strip-shaped film Fw protruding through the slit 35 are positioned on the other surface 65b side of the reflector 65.

[0046] The light sensor 61 is positioned at a distance from the reflector 65 such that both ends T of the strip-shaped film Fw can pass through. Therefore, both ends T of the strip-shaped film Fw, which are positioned on the surface 65b side of the reflector 65, are located between the light sensor 61 and the reflector 65.

[0047] The optical sensor 61 is a reflective fiber sensor. The optical sensor 61 is electrically connected to the control device 70. The optical sensor 61 is positioned facing the surface 65b of the reflector 65. The sensor holder 62 holds the optical sensor 61.

[0048] The support block 63 extends in the width direction. The support block 63 is fixed to the frame of the horizontal bag-making, filling, and packaging machine 10. The sensor holder 62 is fastened to the support block 63 by screws (not shown). The support block 63 supports the sensor holder 62 from below.

[0049] The support block 63 has one end in the width direction in contact with the surface 65b of the reflector 65. The reflector 65 is fastened to the support block 63 by screws 69. In this way, the reflector 65 is supported by the support block 63.

[0050] The optical sensor 61 comprises an optical fiber head 71 and an optical fiber cable 72. The optical fiber cable 72 comprises an optical fiber for transmitting light 72A and an optical fiber for receiving light 72B.

[0051] The optical fiber head 71 is formed in a cylindrical shape that covers the tips of the light-emitting optical fiber 72A and the light-receiving optical fiber 72B. The sensor holder 62 has a rectangular parallelepiped shape and has a retaining hole 62C and a notch 62D. The retaining hole 62C is a through hole that penetrates the sensor holder 62A in the width direction. The notch 62D communicates with the retaining hole 62C, the top surface and side surface of the sensor holder 62A. The optical fiber head 71 is held by fitting into the retaining hole 62C of the sensor holder 62A. The optical fiber cable 72 protrudes to the outside from the retaining hole 62C or the notch 62D of the sensor holder 62A.

[0052] The tip surfaces of the light-emitting optical fiber 72A and the light-receiving optical fiber 72B face the other surface 65b of the reflector 65. The light-emitting optical fiber 72A guides light emitted from a light-emitting unit (not shown) and illuminates the other surface 65b of the reflector 65. The light-emitting unit is composed of, for example, a light-emitting element such as an LED or a laser diode. The light-emitting unit is driven by a control signal from the control device 70.

[0053] The reflected light, illuminated by the light-emitting optical fiber 72A and reflected by the other surface 65b of the reflector 65, is guided to the light-receiving optical fiber 72B and received by a light-receiving unit (not shown). The light-receiving unit is composed of, for example, a light-receiving element such as a phototransistor. The light-receiving unit outputs a light-receiving signal to the control device 70 at a level corresponding to the amount of light received. The control device 70 determines whether or not detection has occurred by comparing the level of the light-receiving signal output from the light-receiving unit with a predetermined threshold.

[0054] The control device 70 detects the positioning mark M when the level of the light-receiving signal output from the light-receiving unit passes a predetermined threshold. In this specification, "passing the threshold" refers to a switch from a state where the level of the light-receiving signal is less than the threshold, or a state where the level of the light-receiving signal is greater than the threshold, to the other state.

[0055] For example, in a strip-shaped film Fw, if the printing density of the positioning mark M is higher than that of other parts, the light transmittance of the positioning mark M is lower than that of other parts. When the positioning mark M is located between the light sensor 61 and the surface 65b of the reflector 65, both ends T of the strip-shaped film Fw (the ends T of two strip-shaped films Fw) are located between the light sensor 61 and the surface 65b of the reflector 65, so the reflected light reflected by the reflector 65 is attenuated more significantly than when other parts are located there. Therefore, the control device 70 can determine that the positioning mark M has been detected when the level of the received light signal output from the light receiving unit switches from a state greater than a predetermined threshold to a state less than a predetermined threshold (passes the threshold), and can determine that the positioning mark M has not been detected when the level of the received light signal is above the predetermined threshold.

[0056] Furthermore, in the strip-shaped film Fw, if the printing density of the positioning mark M is lower than that of other parts, the light transmittance of the positioning mark M is higher than that of other parts. When the positioning mark M is located between the light sensor 61 and the surface 65b of the reflector 65, the reflected light reflected by the reflector 65 is amplified compared to when other parts are located there. Therefore, the control device 70 can determine that the positioning mark M has been detected when the level of the received light signal output from the light receiving unit switches from a state where it is less than a predetermined threshold to a state where it is greater than a predetermined threshold (passes the threshold), and can determine that the positioning mark M has not been detected when the level of the received light signal is below the predetermined threshold. As described above, the light sensor 61 can detect the positioning mark M at the position between the light sensor 61 and the surface 65b of the reflector 65 (detection position DP).

[0057] The control device 70 operates the cutting device 55 when the strip-shaped film Fw has been transported by a predetermined amount from the detection position DP, where the positioning mark M is detected by the positioning mark detector 60. In this embodiment, the "determined amount of feed" is the distance in the transport direction from the detection position DP to the cutter 56.

[0058] The horizontal bag-making, filling, and packaging machine 10 is configured to transport a strip of film Fw by a predetermined amount from the detection position DP. For example, an encoder is provided to measure the rotation speed of the feed motor 24. In this case, the control device 70 stores in advance a predetermined amount of rotation of the feed motor 24 when transporting the strip of film Fw by a predetermined amount. The control device 70 then operates the cutting device 55 when the feed motor 24 has rotated to a predetermined amount from the moment the positioning mark M is detected by the optical sensor 61 (from the moment the ON signal is input). As a result, the cutting device 55 can cut the sealed portion of the strip of film Fw that has been sealed by the end sealing device 50. The moment the optical sensor 61 detects the positioning mark M is when the level of the light signal received by the optical sensor 61 passes a predetermined threshold.

[0059] [Effects of the Embodiment] According to the above embodiment, positioning marks M formed at predetermined intervals D on the strip-shaped film Fw are detected by an optical sensor 61 positioned downstream of the cylinder-making machine 29 in the transport direction and upstream of the end-sealing device 50 in the transport direction. This allows for a reduced predetermined feed amount from the detection position DP for detecting the positioning marks M to the operation of the cutting device 55. As a result, the number of positioning marks M included in this feed amount is also reduced, thereby reducing the deviation of the cutting position when cutting the sealed portion of the strip-shaped film Fw.

[0060] Conventionally, in horizontal bag-making, filling, and packaging machines, tension is sometimes applied to the strip of film Fw to achieve so-called "tight packaging," where the strip of film Fw is wrapped along the outer circumference of the product. However, when tight packaging products that are prone to expansion or have an irregular shape, the product may pull on the strip of film Fw, causing it to meander. Therefore, until now, there has been no idea to attach a sensor downstream of the cylinder-making machine to prevent the positioning mark M from being missed due to the meandering of the strip of film Fw.

[0061] However, in recent years, improvements in the technology of packaging material feeding devices, clamping and conveying devices (film pulling rollers), and center sealing devices have reduced the meandering of the strip-shaped film Fw in horizontal bag-making, filling, and packaging machines. Therefore, in the horizontal bag-making, filling, and packaging machine 10 of this embodiment, it has become possible to position the optical sensor 61 downstream of the cylinder maker 29 in the conveying direction and upstream of the end sealing device 50 in the conveying direction.

[0062] Furthermore, by positioning the optical sensor 61 upstream of the center sealing device 40 in the transport direction, the positioning marks M can be detected before the end T of the strip-shaped film Fw is heated and sealed. More specifically, the center sealing device 40 seals the end T by heat welding, causing the strip-shaped film Fw to expand and contract. The rate of expansion and contraction due to heat welding differs depending on the type of strip-shaped film Fw. In other words, the shape of the positioning marks M and the spacing D between the positioning marks M change depending on the type of strip-shaped film Fw, due to the center sealing device 40. In contrast, according to the above embodiment, since the optical sensor 61 is positioned upstream of the center sealing device 40 in the transport direction, the positioning marks M can be detected before the end T of the strip-shaped film Fw is heat-sealed by the center sealing device 40. Therefore, it is possible to accurately detect the positioning marks M, and the deviation of the cutting position when cutting the sealed portion of the strip-shaped film Fw can be reduced.

[0063] Furthermore, in the above embodiment, for example, when the supply of product P by the supply device is stopped, control is performed to stop the operation of the horizontal bag-making, filling, and packaging machine 10 (including the center seal device 40) so as not to create empty bags Bp.Therefore, when the horizontal bag-making, filling, and packaging machine 10 is stopped and then immediately restarted (when the strip-shaped film Fw heated by the heater bars 41 and 42 of the center seal device 40 is still hot when restarted), and when it is restarted after some time has passed (when the strip-shaped film Fw heated by the heater bars 41 and 42 has cooled down when restarted), the expansion and contraction rate due to heat sealing will be different.In contrast, according to the above embodiment, since the optical sensor 61 is positioned upstream of the center seal device 40 in the conveying direction, the positioning mark M can be accurately detected regardless of the stop control of the horizontal bag-making, filling, and packaging machine 10.

[0064] Furthermore, since the end T has not yet been marked by the marking rollers 45 and 46, the positioning mark M can be accurately detected. Also, the marks (multiple circumferential grooves formed on the outer surface) of the marking rollers 45 and 46 come in various types depending on the manufacturer's preference, including groove width and number. The expansion and contraction rate of the strip-shaped film Fw differs depending on the type of marks on the marking rollers 45 and 46, but in this embodiment, the positioning mark M can be detected before it is held between the marking rollers 45 and 46, so the positioning mark M can be accurately detected.

[0065] Furthermore, by positioning the optical sensor 61 upstream of the gripping and conveying device 30 in the conveying direction, the positioning marks M can be detected before both ends T of the strip-shaped film Fw are gripped by the film pulling rollers 32 and 33. In other words, the positioning marks M can be detected before any irregularities are created on the ends T of the strip-shaped film Fw or the positioning marks M by gripping with the film pulling rollers 32 and 33, thus enabling more accurate detection of the positioning marks M.

[0066] Furthermore, the end T of the strip film Fw is constantly subjected to tension in the conveying direction as it is transported from the film pulling rollers 32 and 33 to the weight rollers 45 and 46. Since the elongation rate differs for each type of strip film Fw, the tension received from the film pulling rollers 32 and 33 and the weight rollers 45 and 46 also differs. This tension causes the strip film Fw to expand and contract, resulting in changes to the shape of the positioning marks M and the spacing D between them for each type of strip film Fw.

[0067] In contrast, according to the above embodiment, since the optical sensor 61 is positioned upstream of the film pulling rollers 32 and 33 in the transport direction, the positioning mark M can be detected before it receives tension from the film pulling rollers 32 and 33 and the weighting rollers 45 and 46. Therefore, it is possible to accurately detect the positioning mark M and reduce the deviation of the cutting position when cutting the sealed portion of the strip-shaped film Fw.

[0068] Furthermore, by positioning the optical sensors 61A and 61B below the support plate 31, it is possible to prevent the product P from being mistakenly detected as the positioning mark M. As a result, the positioning mark M can be detected with even greater accuracy.

[0069] [Differentiation] Next, a modified example will be described. Figure 8 shows a positioning mark detector 80 according to a modified example. In the above embodiment, the positioning mark detector 60 is equipped with only one optical sensor 61, but the positioning mark detector 80 of this modified example is equipped with two optical sensors 61A and 61B. The optical sensors 61A and 61B are arranged on both sides of the reflector 65 in the width direction.

[0070] In this modified example, the reflector 65 is positioned so that its width is aligned with the center line CL of the slit 35. Therefore, the pair of ends T of the strip-shaped film Fw protruding through the slit 35 are positioned on both sides of the reflector 65 in the width direction. The light sensor 61B and sensor holder 62B have the same configuration as the light sensor 61 and sensor holder 62 in the above embodiment. The support block 63B has the same configuration as the support block 63 in the above embodiment.

[0071] Note that the optical sensor 61A and sensor holder 62A have the same configuration as the optical sensor 61B and sensor holder 62B, and are arranged symmetrically with the optical sensor 61B and sensor holder 62B, so a detailed explanation is omitted. The sensor holder 62A is fastened to the support block 63A with screws (not shown). The support block 63A, together with the reflector 65, is fastened to the support block 63B with screws 69. As a result, the support blocks 63A and 63B are integrated and support the sensor holders 62A and 62B from below.

[0072] The light sensors 61A and 61B are positioned in the width direction at a distance from the reflector 65 that allows the strip-shaped film Fw to pass through. Therefore, the ends T of the strip-shaped film Fw, which are positioned on both sides of the reflector 65, are located between the light sensors 61A and 61B and the reflector 65, respectively.

[0073] The leading edges of the light-emitting optical fiber 72A and the light-receiving optical fiber 72B of the light sensor 61A face one surface 65a of the reflector 65. The reflected light, illuminated by the light-emitting optical fiber 72A and reflected by one surface 65a of the reflector 65, enters the light-receiving optical fiber 72B and is received by the light-receiving unit. The control device 70 determines whether detection has occurred by comparing the level of the received signal output from the light-receiving unit with a predetermined threshold.

[0074] For example, similar to the embodiment described above, if the positioning mark M has a higher printing density than other parts of the strip-shaped film Fw, when the positioning mark M is located between the light sensor 61A and the surface 65a of the reflector 65, the reflected light reflected by the reflector 65 is attenuated compared to when other parts are located there. Therefore, the control device 70 can determine that the positioning mark M has been detected when the level of the received light signal output from the light receiving unit switches from a state greater than a predetermined threshold to a state less than a predetermined threshold (passes the threshold), and can determine that the positioning mark M has not been detected when the level of the received light signal is above the predetermined threshold.

[0075] Furthermore, in the strip-shaped film Fw, if the printing density of the positioning mark M is lower than that of other parts, when the positioning mark M is located between the light sensor 61A and the surface 65a of the reflector 65, the reflected light reflected by the reflector 65 is amplified compared to when other parts are located there. Therefore, the control device 70 can determine that the positioning mark M has been detected when the level of the received light signal output from the light receiving unit switches from a state where it is less than a predetermined threshold to a state where it is greater than a predetermined threshold (passes the threshold), and can determine that the positioning mark M has not been detected when the level of the received light signal is below the predetermined threshold. As described above, the light sensor 61A can detect the positioning mark M at a position (detection position DP) between the light sensor 61A and one surface 65a of the reflector 65.

[0076] The leading edges of the light-emitting optical fiber 72A and the light-receiving optical fiber 72B of the light sensor 61B face the other surface 65b of the reflector 65. The reflected light, illuminated by the light-emitting optical fiber 72A and reflected by the other surface 65b of the reflector 65, enters the light-receiving optical fiber 72B and is received by the light-receiving unit. Similar to the light sensor 61A, the light sensor 61B can detect the positioning mark M at a position (detection position DP) between the light sensor 61B and the other surface 65b of the reflector 65.

[0077] The control device 70 operates the cutting device 55 when the strip-shaped film Fw has been transported a predetermined amount from the detection position DP where the positioning mark M is detected by the positioning mark detector 60. This allows the cutting device 55 to cut the sealed portion of the strip-shaped film Fw that has been sealed by the end sealing device 50. The point at which the optical sensors 61A and 61B detect the positioning mark M is when the level of the received light signal in one or both of the optical sensors 61A and 61B passes a predetermined threshold. In this way, the optical sensors 61A and 61B can detect the positioning mark M at the detection position DP, and thus the same effects as in the above embodiment can be obtained.

[0078] Furthermore, horizontal bag-making, filling, and packaging machines 10 are often used to package a wide variety of products. Accordingly, the types of strip films Fw used in the horizontal bag-making, filling, and packaging machine 10 also need to accommodate a wide variety of products. In addition, the printing of positioning marks M differs for each strip film Fw. More specifically, the position and surface on which the positioning marks M are printed at the end T of the strip film Fw differ for each strip film Fw.

[0079] In contrast, in this modified example, a reflector 65 is positioned between the ends T of the strip-shaped film Fw, and light sensors 61A and 61B are provided on both sides in the width direction of the ends T. Therefore, it can accommodate cases where the positioning mark M is printed on both ends T or on only one end T. Furthermore, from the perspective of the light sensors 61A and 61B, the positioning mark M is located between the light sensors 61A and 61B and the reflector 65 regardless of whether the positioning mark M is printed on the back or front surface of the strip-shaped film Fw. For this reason, the positioning mark M can be detected. In other words, in this modified example, it is possible to detect positioning marks M printed at various positions that differ for each strip-shaped film Fw, and it can accommodate a wide variety of strip-shaped films Fw.

[0080] The embodiments and modifications described above are illustrative for the purpose of explaining the present invention and are not intended to limit the scope of the present invention to those embodiments only. Those skilled in the art can modify the invention as appropriate without departing from the spirit of the invention.

[0081] For example, in the above embodiments and modifications, a configuration using reflective optical sensors 61A and 61B and a reflector 65 as positioning mark detectors 60 and 80 is illustrated, but the system is not limited to this, and a camera using an image sensor may also be used. In this case, for example, the camera is placed in the same position as the optical sensors 61A and 61B in the above embodiments and modifications. The control device 70 may then analyze the captured image taken by the camera to determine whether or not there is a positioning mark M. [Explanation of Symbols]

[0082] 10 Horizontal bag-making, filling, and packaging machine 11. Supply conveyor 14 Drive sprocket 15 Driven sprocket 16 Conveyor chain 17 Drive motor 18 Pusher 20 Packaging material feeding device 21 Holder Unit 22 drive rollers 23 Driven roller 24 Feed motor 25a, 25b Guide rollers 29 Tube maker 30. Clamping and conveying device 31 Support plate 32, 33 Film pulling roller 34 Pull motor 40 Center seal device 41, 42 Heater bars 43, 44 Crimping rollers 50 End seal device 51, 52 Seal Block 55 Cutting device 56 cutters 60, 80 Positioning Mark Detectors 61A, 61B Optical Sensor 62A, 62B Sensor Holder 63 Support Block 65 Reflector

Claims

1. A horizontal bag-making, filling, and packaging machine that fills products into bags formed from strip-shaped packaging material, A cylinder-forming device that forms a cylindrical shape by overlapping both ends of the strip-shaped packaging material in the width direction perpendicular to the conveying direction, A clamping and conveying device is positioned downstream of the cylinder forming machine in the conveying direction, and clamps both overlapping ends of the strip-shaped packaging material and conveys it in the conveying direction. A center sealing device is positioned downstream from the cylinder-making machine in the conveying direction and seals the overlapping ends of the cylindrical strip-shaped packaging material. An end sealing device is positioned downstream of the center sealing device in the conveying direction and seals both sides of the bag containing the product from the strip-shaped packaging material formed into a cylindrical shape by the center sealing device, A cutting device for cutting the sealed portion of the strip-shaped packaging material sealed by the end sealing device, A sensor for detecting positioning marks formed on the strip-shaped packaging material at predetermined intervals in the transport direction, The system includes a control device that operates the cutting device to cut the sealed portion when the strip-shaped packaging material has been transported by a predetermined amount from the detection position where the positioning mark is detected by the sensor, A horizontal bag-making, filling, and packaging machine characterized in that the sensor is positioned downstream of the cylinder-making device in the conveying direction and upstream of the end-sealing device in the conveying direction.

2. In the horizontal bag-making, filling, and packaging machine described in claim 1, A horizontal bag-making, filling, and packaging machine characterized in that the sensor is positioned upstream of the center seal device in the conveying direction.

3. In the horizontal bag-making, filling, and packaging machine described in claim 1, A horizontal bag-making, filling, and packaging machine characterized in that the sensor is positioned upstream of the gripping and conveying device in the conveying direction.

4. In the horizontal bag-making, filling, and packaging machine described in claim 1, The support plate provides support for the product enclosed in the aforementioned strip-shaped packaging material from above, and has slits formed therein that cause the overlapping ends of the strip-shaped packaging material to protrude downward. A horizontal bag-making, filling, and packaging machine characterized in that the sensor is positioned below the support plate.

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