Packaging apparatus and packaging material adhesion preventing member

Abstract

To prevent the occurrence of a failure caused by the fact that a first packaging material and a second packaging material are brought into close contact with each other in an area other than a joining area to form a product in which a close contact area is formed.SOLUTION: A packaging machine 1 for packaging an object 100 to be packaged by winding an upper film F1 which is a first packaging material and a lower film F2 which is a second packaging material around the object 100 to be packaged in a state where tips of the upper film F1 and the lower film F2 are welded includes separators 26 which are plate-shaped packaging material adhesion preventing members positioned between the upper film F1 and the lower film F2 on an upstream side in a conveying direction with respect to a welding part Fx and preventing the upper film LA and the lower film LA from adhering to each other.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a packaging device and a member for preventing packaging material from sticking together. [Background technology]

[0002] In Patent Document 1, the present applicant has proposed a packaging device that packages an item by placing the item on a backing sheet and wrapping a film around the item together with the backing sheet so that the film is tightly attached. This packaging device packages the item placed on the backing sheet with two strips of packaging material, such as film. The leading edge of the item abuts two sheets of packaging material whose leading edges are joined together, and as the item moves downstream in the conveying direction, the two sheets of packaging material pressed by the item wrap around the item, wrapping it around the item. The packaging process is completed by joining the two sheets of packaging material upstream of the rear end of the item. In this packaging device, the two sheets of packaging material are stretched and joined together upstream of the rear end of the item, allowing the contracting force of the film to secure the item to the backing sheet. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-98242 [Patent Document 2] Japanese Patent Application Publication No. 2019-172287 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when the packaging device described in Patent Document 1 was used to create a finished product in which an item was fixed to a backing sheet, the film that had been adhering to the backing sheet and the item sometimes loosened, causing the item to become unfixed to the backing sheet. [Means for solving the problem]

[0005] In order to solve the above-mentioned problems, the present invention provides a packaging system that includes a conveying means for conveying an item to be packaged, a first packaging material supplying means for supplying one of two strip-shaped packaging materials for packaging the item to be packaged, a second packaging material supplying means for supplying the other, a second packaging material, and a joining means for joining the first packaging material and the second packaging material so as to form a joining region extending in a width direction perpendicular to the conveying direction by the conveying means, and in which the leading ends of the packaged item in the conveying direction hit the first packaging material and the second packaging material whose leading ends are joined together, and the packaged item moves further downstream in the conveying direction, so that the packaged item is pressed against the packaged item. The first packaging material and the second packaging material are supplied from a first packaging material supply means and a second packaging material supply means while being wrapped around the packaged item, and after the rear end of the packaged item in the conveying direction passes a joining position of the joining means, the joining means joins the first packaging material and the second packaging material together, thereby wrapping the first packaging material and the second packaging material around the packaged item to package it. In this packaging device, the first packaging material and the second packaging material are supplied from a first packaging material supply means and a second packaging material supply means while being wrapped around the packaged item, and after the rear end of the packaged item in the conveying direction passes a joining position of the joining means, the joining means joins the first packaging material and the second packaging material together, thereby wrapping the first packaging material and the second packaging material around the packaged item to package it.

[0006] As a result of extensive research, the present inventors have found that the above-mentioned problem occurs for the following reasons. That is, a tightly adhered region where the packaging materials (films) are in close contact with each other may form upstream in the conveying direction from the joint region (welded portion) between the two packaging materials (films) before the leading ends of the packaged items collide. Even when the leading ends of the packaged items collide, this tightly adhered region may not be resolved, and packaging may continue as is. In a product obtained with such a tightly adhered region, if the tightly adhered region is resolved for some reason, a gap may form between the leading ends of the packaged items and the joint region. In a product produced by the packaging device described in Patent Document 1, in which the product is secured to the backing by the force of the packaging material's shrinkage, the gap loosens the packaging material that was in close contact with the backing and the item, releasing the product from the backing. Therefore, by preventing the formation of a tightly adhered region that does not dissolve during packaging, the aforementioned problem of the product being released from the backing can be prevented. The problem of creating a product with such a tightly sealed area is not limited to products that use the shrinking force of the packaging material to secure the product to the backing. In products that cover the packaged item with two sheets of packaging material and form a sealed area at least at the front and rear in the conveying direction, a gap will form between the leading edge of the packaged item and the sealed area, resulting in a product that is larger than necessary for the size of the packaged item, resulting in problems such as an oversized product and increased packaging material consumption. [Effects of the Invention]

[0007] According to the present invention, by providing a packaging material adhesion prevention member, it is possible to prevent the first packaging material and the second packaging material from adhering to each other outside the joining area, and to prevent the formation of an adhesion area, which has the excellent effect of preventing defects caused by the creation of a finished product with an adhesion area still formed. In particular, in the case of a packaging device in which the packaged item is an item placed on a backing sheet and the item can be fixed to the backing sheet by the force of the packaging material trying to shrink, the formation of an adhesion area can prevent the packaging material that has been in close contact with the backing sheet and the item from loosening, thereby preventing the problem of the item becoming unfixed to the backing sheet. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view of a packaging machine according to an embodiment. [Figure 2] FIG. 2 is a front view of the packaging machine of FIG. 1. [Figure 3] 2 is a schematic cross-sectional side view of the packaging machine of FIG. 1. [Figure 4] FIG. 2 is a horizontal cross-sectional view of the packaging machine of FIG. 1. [Figure 5] FIG. 2 is a perspective view showing a packaged product wrapped in a film by the packaging machine of FIG. 1 . [Figure 6] 6(a) to 6(c) are diagrams explaining the operation of the packaging machine in chronological order. [Figure 7] 7(a) to 7(c) are diagrams explaining the operation of the packaging machine in chronological order. [Figure 8]8(a) to 8(c) are diagrams explaining the operation of the packaging machine in chronological order. [Figure 9] FIG. 10 is a comparative diagram of a configuration with and without an upper film pressing member. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. The description of the embodiments is for illustrative purposes only and does not limit the invention, and the features and combinations thereof described in the embodiments are not necessarily essential to the invention. The same or equivalent components, parts, and processes shown in each drawing are designated by the same reference numerals, and redundant explanations may be omitted as appropriate. In addition, the dimensions of the components in each drawing may be enlarged or reduced as appropriate to facilitate understanding. In addition, some components that are not important for explaining the embodiments may be omitted from each drawing.

[0010] Fig. 1 is a perspective view of a packaging machine 1 according to an embodiment, Fig. 2 is a front view of the packaging machine 1 of Fig. 1, and Fig. 3 is a schematic side cross-sectional view showing an outline of the interior of the packaging machine 1 of Fig. 1. Fig. 4 is a plan cross-sectional view seen from above of a horizontal cross section at the position of the vertical conveying path of the packaging machine 1 of Fig. 1. Fig. 5 is a perspective view showing a packaged product 200 in which an item 100 to be packaged is wrapped in a film F by the packaging machine 1. The packaging machine 1 is a stretch packaging device that wraps the item 100 to be packaged using the stretchability of the film F to create the packaged product 200.

[0011] The packaged item 100 includes a backing sheet 102, which is a plate-shaped support material, and an item 104 placed on the backing sheet 102. The backing sheet 102 is, for example, cardboard. The shape of the backing sheet 102 is not particularly limited, but in this example, it is rectangular when viewed from the normal direction of the surface on which the item 104 is placed.

[0012] The item 104 contained in the packaged item 100 is, for example, a product purchased from an e-commerce site (e.g., an online store's mail-order site), and the packaged item 100 is stretch-wrapped in film F as a packaged product 200, which is then packed in a packaging box, such as a cardboard box, and delivered to the purchaser.

[0013] The packaging machine 1 sandwiches an item 100 to be packaged between two sheets of film F (F1, F2) supplied from two film rolls R (R1, R2) and welds them at a welding section Fx to create a packaged product 200. The packaging machine 1 is a device that packages an item 104 together with a backing sheet 102 with film F, and can also be considered a device that fixes the item 104 to the backing sheet 102 with film F.

[0014] The packaging machine 1 has an insertion opening 2 located at the right end in FIG. 3 and an ejection opening 4 located at the left end in FIG. 3. In the packaging machine 1, the packaged item 100 is inserted into the packaging machine 1 through the insertion opening 2 so that one side of a rectangular backing sheet 102 is parallel to the width direction (the X-axis direction in FIGS. 1 to 4). On the outside of the insertion opening 2, an entrance bottom guide 21 that guides the bottom of the packaged item 100 inserted into the insertion opening 2 and side guides 22 that guide both sides in the width direction are provided, making it easy for the user to insert the packaged item 100 by hand. In addition, as shown in FIG. 2, the opening width in the vertical direction of the insertion opening 2 is wide at the center in the width direction and narrow at the outer sides in the width direction. This is because only the backing sheet 102 passes through the outer sides in the width direction, and the opening width is wide in the center in the width direction so that an item 104 of a certain height placed on the backing sheet 102 can pass through.

[0015] In this embodiment, the packaged item 100 is inserted manually by the user, but instead of the guide members (entrance underside guide 21, side guide 22), a device that automatically supplies the packaged item 100 in portions can be connected to enable automatic supply.

[0016] The inserted packaged item 100 is conveyed through the device in the direction of arrow "α" in Fig. 1 with its upper and lower sides sandwiched between films F (F1, F2) drawn out from the upper film roll R1 above it and the lower film roll R2 below it, and is packaged by heat welding the leading and trailing ends in the conveying direction α, and is then discharged from the discharge outlet 4 and sequentially ejected onto a packaged item tray 40. In the conveying direction α from the insertion opening 2 toward the discharge opening 4, the insertion opening 2 side is called the upstream side, and the discharge opening 4 side is called the downstream side.

[0017] As shown in Fig. 1, an operation panel 45 is provided on the upper surface of the left wall portion 10b of the housing on the left side in the width direction of the packaging machine 1. The operation panel 45 functions as an input unit that accepts various inputs from the user for operating the packaging machine 1, and also functions as a display unit that displays various information within the packaging machine 1. As shown in Fig. 2, a power switch 46 that turns on power to the packaging machine 1 is provided on the front of the right wall portion 10a of the housing on the right side in the width direction of the packaging machine 1.

[0018] The packaged item 100 is inserted through the insertion opening 2 so that two opposing sides of the backing sheet 102 are parallel or approximately parallel to the conveying direction α. ​​The packaging machine 1 packages the packaged item 100 inserted through the insertion opening 2 with film F before it is discharged from the discharge opening 4.

[0019] 3, the packaging machine 1 includes an upper roll support shaft 61, a lower roll support shaft 62, an upstream hold-down member 11, an upstream hold-down receiving portion 41, a heater 13, a heater receiving portion 42, a downstream hold-down member 12, and a downstream hold-down receiving portion 43. The heater 13 is supported by a heater support member 14, and the downstream hold-down member 12 is supported by a downstream hold-down supporting member 15, and the downstream hold-down supporting member 15 is configured to move up and down together with the downstream hold-down member 12.

[0020] Furthermore, the packaging machine 1 includes an entrance roller pair 31 (entrance lower roller 31a, entrance upper roller 31b), an upstream conveying roller pair 32 (upstream lower conveying roller 32a, upstream upper conveying roller 32b), a downstream conveying roller pair 33 (downstream lower conveying roller 33a, downstream upper conveying roller 33b), and an exit roller pair 34 (exit lower roller 34a, exit upper roller 34b). The lower rollers of each roller pair (entrance lower roller 31a, upstream lower conveying roller 32a, downstream lower conveying roller 33a, exit lower roller 34a) are rotationally driven drive rollers. Furthermore, the packaging machine 1 includes an entrance sensor S1, a heater passage sensor S2, an exit sensor S3, and a control unit 30.

[0021] The upper roll support shaft 61 is inserted into the core (e.g., a cardboard tube) of the upper film roll R1 and rotatably supports the upper film roll R1. The upper roll support shaft 61 is particularly provided so that the upper film roll R1 is located above the insertion opening 2.

[0022] The lower roll support shaft 62 is inserted into the core of the lower film roll R2 and rotatably supports the lower film roll R2. The lower roll support shaft 62 is particularly provided so that the lower film roll R2 is located below the insertion opening 2. The two film rolls R (R1, R2) are formed by winding films F (F1, F2) made of long continuous film around a core.

[0023] The upper roll support shaft 61 is supported relative to the main body of the packaging machine 1 so as to be slidable in the vertical direction, and an upper roll support roller 51 is provided below the upper roll support shaft 61, which contacts the lower edge of the surface of the upper film roll R1. As the upper film F1 is consumed and the diameter of the upper film roll R1 decreases, the upper roll support shaft 61 moves downward to approach the upper roll support roller 51, with the lower edge of the surface of the upper film roll R1 supported by the upper roll support roller 51. Similarly, the lower roll support shaft 62 is supported relative to the main body of the packaging machine 1 so as to be slidable in the vertical direction, and a lower roll support roller 54 is provided below the lower roll support shaft 62, which contacts the lower edge of the surface of the lower film roll R2. As the lower film F2 is consumed and the diameter of the lower film roll R2 decreases, the lower roll support shaft 62 moves downward to approach the lower roll support roller 54, with the lower edge of the surface of the lower film roll R2 supported by the lower roll support roller 54.

[0024] An upper film F1 is pulled out from the upper film roll R1 and is placed around an upper film first guide 52 and an upper film second guide 53, with its leading end positioned above the heater receiving section 42. A lower film F2 is pulled out from the lower film roll R2 and is placed around a lower film guide 55, with its leading end positioned above the heater receiving section 42. As shown in FIG. 5, the films F (F1, F2) are narrower in width (length in the width direction, which is the direction perpendicular to the conveying direction α and perpendicular to the plane of the paper in FIG. 3) than the backing sheet 102 of the packaged item 100. As a result, both sides of the backing sheet 102 of the packaged product 200 in the width direction are not covered by the film F and are exposed.

[0025] The leading ends of the two films F (F1, F2) were welded together (i.e., connected) during the previous packaging operation, forming a welded portion Fx. Furthermore, the two film rolls R (R1, R2) are supported so as to be freely rotatable, as described above. Therefore, when the packaged item 100 is inserted and moves downstream, the welded leading ends of the films F (F1, F2) are pushed by the leading ends of the packaged item 100 and move downstream together with the packaged item 100, and the films F (F1, F2) are pulled out from the two film rolls R (R1, R2) by the distance the leading ends have moved.

[0026] The film F is transparent, although not particularly limited. The film F is a stretch film that is stretchable at least in the conveying direction α. ​​Having stretchability in the conveying direction α means that the film stretches without breaking when a tensile force is applied in the conveying direction α, and shrinks when the tensile force is removed. It does not matter whether the film returns to its original state, i.e., to its original length, when the tensile force is removed. The direction in which the film F is stretched when wrapping the packaging material is the wrapping direction.

[0027] As shown in Figure 3, in the packaging machine 1, the upstream presser member 11, heater 13, and downstream presser member 12 are arranged in this order from the upstream side. An upstream presser receiving portion 41 is provided below the upstream presser member 11, a heater receiving portion 42 is provided below the heater 13, and a downstream presser receiving portion 43 is provided below the downstream presser member 12. Each receiving portion (41, 42, 43) has a flat receiving upper surface. The upstream presser member 11, upstream presser receiving portion 41, heater 13, heater receiving portion 42, downstream presser member 12, and downstream presser receiving portion 43 are all members that are elongated in the width direction.

[0028] The upstream press member 11 can be raised and lowered by a drive mechanism (not shown). In the illustrated example, the bottom surface of the upstream press member 11 is flat, but this is not limited thereto and may be, for example, a curved surface.

[0029] The heater 13 is supported by a heater support member 14, and the downstream hold-down member 12 is supported by the heater support member 14 via a downstream hold-down support member 15. The heater support member 14 can be raised and lowered by a drive mechanism (not shown). Therefore, the heater 13 and the downstream hold-down member 12 can be raised and lowered in conjunction with the raising and lowering of the heater support member 14. In this case, only one drive mechanism is required to raise and lower the heater 13 and the downstream hold-down member 12, which reduces costs. However, the heater 13 and the downstream hold-down member 12 may be raised and lowered by separate drive mechanisms. In this case, a mechanism for moving the downstream hold-down support member 15 up and down together with the downstream hold-down member 12 is not required.

[0030] The downstream presser support member 15 is supported by the heater support member 14 so that the downstream presser member 12 is movable up and down relative to the heater 13. The downstream presser member 12 is biased downward, i.e., toward the upper surface of the downstream presser receiving portion 43, by a spring 16 whose one end (upper end) is fixed to the heater support member 14 and whose other end (lower end) is fixed to the downstream presser support member 15.

[0031] The lower surface of the downstream press member 12 is a flat surface, but is not limited to this and may be, for example, a curved surface.

[0032] The heater 13 is made of, for example, aluminum or an aluminum alloy, which has good thermal conductivity and is lightweight. The lower end of the heater 13 is formed at an acute angle. A rubber heater (not shown) is baked and fixed to the heater 13, and the heater 13 can be heated by passing electricity through this rubber heater.

[0033] As shown in the figure, the distance "L1" in the conveying direction from the upstream hold-down member 11 to the heater 13 is preferably configured to be longer than the distance "L2" in the conveying direction from the heater 13 to the downstream hold-down member 12. The distance "L1" is, for example, the distance between the center of the lower surface of the upstream hold-down member 11 in the conveying direction α and the tip of the heater 13. The distance "L2" is, for example, the distance between the tip of the heater 13 and the center of the lower surface of the downstream hold-down member 12 in the conveying direction α.

[0034] An entrance roller pair 31 is provided upstream of the upstream press member 11 to transport the packaged item 100 inserted from the insertion opening 2 downstream. An upstream transport roller pair 32 and a downstream transport roller pair 33 are provided downstream of the downstream press member 12 to transport the packaged item 100 downstream inside the packaging machine 1. An exit roller pair 34 is provided downstream of the downstream transport roller pair 33 to discharge the packaged product 200, in which the packaged item 100 is wrapped in film F, from the discharge opening 4.

[0035] These roller pairs (31, 32, 33, 34) are composed of two roller pairs (only one of which is shown on the far side of the paper, i.e., on the right side in the width direction) spaced apart in the width direction, as shown by the lower rollers (31a, 32a, 33a, 34a) in FIG. 4. The distance between these two roller pairs spaced apart in the width direction is wider than the width of the film F and narrower than the width of the backing sheet 102 of the packaged item 100 to be inserted. Furthermore, when inserting the packaged item 100, it is necessary to place the packaged item 104 on the backing sheet 102 so that the position of the article 104 in the width direction on the backing sheet 102 is inside the two roller pairs spaced apart in the width direction. As a result, the roller pairs (31, 32, 33, 34) are configured to clamp and transport only the backing sheet 102, and the height of the article 104 is not limited by the distance between the rollers of the roller pairs, improving the degree of freedom in the height of the insertable article 104.

[0036] The roller pairs (31, 32, 33, 34) that transport the packaged item 100 are located on the outside in the width direction of the film F (F1, F2), and transport the packaged item 100 by clamping the film F on the leading end side of the film F (F1, F2) on the packaged item 100, or both ends of the backing sheet 102 in the width direction that are not covered by the film F (hereinafter simply referred to as "film F") cut from the film F (F1, F2). In each roller pair (31, 32, 33, 34), the upper roller (31b, 32b, 33b, 34b) contacts the backing sheet 102 from above, and the lower roller (31a, 32a, 33a, 34a) contacts the backing sheet 102 from below. Each pair of rollers (31, 32, 33, 34) sandwiches the backing sheet 102 between the upper and lower rollers and conveys the backing sheet 102, and thus the packaged item 100, downstream.

[0037] The entrance sensor S1 is a transmission type sensor located in the center in the width direction, upstream of the upstream hold-down member 11. The heater passage sensor S2 is a reflective type sensor located in the same position as the downstream hold-down member 12 in the conveying direction or downstream of it, upstream of the upstream conveying roller pair 32, and located in a pair on both outer sides of the downstream hold-down receiving portion 43 in the width direction. The exit sensor S3 is a transmission type sensor located in the center in the width direction, downstream of the exit roller pair 34. Each sensor (S1, S2, S3) detects the presence or absence of the packaged item 100 (or packaged product 200) at its respective detection position, thereby detecting the passage of the leading end and trailing end of the packaged item 100 (or packaged product 200).

[0038] 3 and 4, in the packaging machine 1, an upstream guide plate 71 and a downstream guide plate 72 that support the underside of the packaged item 100 (or packaged product 200) moving within the device are fixed to the device housing. The upstream end of the upstream guide plate 71 is adjacent to the lower film guide 55, and the downstream end of the upstream guide plate 71 is adjacent to the heater receiving portion 42. The upstream end of the downstream guide plate 72 is adjacent to the downstream presser receiving portion 43, and the downstream side of the downstream guide plate 72 extends to the discharge outlet 4.

[0039] 4, the entrance lower roller 31a, the entrance sensor S1, and the upstream presser foot receiving portion 41 are arranged to be exposed upward from openings provided in the upstream guide plate 71. The exit sensor S3 and the exit lower roller 34a are arranged to be exposed upward from openings provided in the downstream guide plate 72. The upstream conveying roller pair 32 and the downstream conveying roller pair 33 are arranged to be located on the outer side in the width direction of the downstream guide plate 72 at the portion where the width of the downstream guide plate 72 narrows.

[0040] The control unit 30 comprehensively controls the packaging machine 1. Specifically, the control unit 30 controls the operation of actuators such as motors that drive each mechanism and the heating of the heater 13 that welds the film F (F1, F2). For example, the control unit 30 starts and stops the conveyance of the packaged item 100 (or packaged item 200) by each roller pair (31, 32, 33, 34) based on the detection results of the packaged item 100 (or packaged item 200) by each sensor (S1, S2, S3).

[0041] 1, 3, and 4, the packaging machine 1 is provided with a plate-shaped separator 25 that extends from the insertion opening 2 to near the upstream end of the heater receiving portion 42. The separator 25 is disposed so as to be located between the upper film F1 and the lower film F2 on the upstream side in the conveyance direction of the heater receiving portion 42, which is the joining position, and functions as a plate-shaped packaging material adhesion prevention member that prevents the upper film F1 and the lower film from adhering to each other.

[0042] The upstream end of separator 25 can be fixed to inlet lower guide 21, and by attaching inlet lower guide 21 to which separator 25 is fixed below insertion port 2 of the packaging machine 1 body and pushing separator 25 made of a flexible material through insertion port 2, only the upstream end is fixed to the packaging machine 1 body, as shown in Figures 3 and 4, and is arranged to extend along the conveying direction of packaged item 100.

[0043] 3 and 4, the position where the upstream end of separator 25 is fixed is upstream of lower film guide 55, which guides lower film F2, which is pulled out from lower film roll R2 and is arranged below upstream guide plate 71 that forms the conveying path, to the height of the conveying path. With this arrangement, separator 25 can be placed between the conveying path of packaged item 100 to be inserted and the moving path of lower film F2.

[0044] 3 and 4, the packaging machine 1 further includes an upper film hold-down member 26, which is a packaging material movement path displacement suppression member that suppresses upward displacement of the movement path from the upper film second guide 53 to the welding unit Fx. The upper film hold-down member 26 is disposed upstream of the heater receiving unit 42 in the conveying direction, and is made of a plate-like flexible material with its upper portion fixed to the device housing and hanging down. As shown in FIG. 3, the lower end of the upper film hold-down member 26 comes into contact with the upper film F1, thereby suppressing upward displacement of the movement path of the upper film F1 toward the heater receiving unit 42, which forms the conveying path of the packaged items 100. Furthermore, when the item 104 placed on the backing sheet 102 has a certain height and the item 104 of the packaged item 100 moving in the conveying direction α comes into contact with the upper film holding member 26 through the upper film F1, the upper film holding member 26 bends so that the lower end of the upper film holding member 26 moves downstream in the conveying direction, allowing the packaged item 100 including the item 104 to pass through.

[0045] The above is the basic configuration of the packaging machine 1. Next, an example of its operation will be described.

[0046] 6(a)-(c), 7(a)-(c), and 8(a)-(c) are enlarged views of the vicinity of the conveying path in the side cross-sectional view of the packaging machine 1 shown in FIG. 3, and are diagrams illustrating an example of the operation of the packaging machine 1 in chronological order. In FIG. 3, the upstream presser member 11, heater 13, and downstream presser member 12 are in standby positions spaced above the upper receiving surfaces of the respective receiving portions (41, 42, 43). In this state, the packaged item 100 is inserted into the packaging machine 1. The standby positions are positions (heights) at which the upstream presser member 11, heater 13, and downstream presser member 12 do not come into contact with the packaged item 100 being inserted. In the standby position, the lower end of the downstream presser member 12 is positioned below the lower end of the heater 13 (near the upper surface of the receiving portion). In the standby state, each conveying roller pair (entrance roller pair 31, upstream conveying roller pair 32, downstream conveying roller pair 33, and exit roller pair 34) that applies a conveying force to the packaged item 100 is stopped.

[0047] Figure 6(a) shows the state in which an item 100 to be packaged has been inserted into the packaging machine 1 and the leading edge of the item 100 has passed the detection position of the inlet sensor S1. The control unit 30 starts driving the rotation of each conveying roller pair (31, 32, 33, 34) at the point in time when the inlet sensor S1 detects the leading edge of the inserted item 100. As a result, both widthwise ends of the backing sheet 102 of the item 100 to be packaged, which has been pushed further in from the state in Figure 6(a), are clamped by the inlet roller pair 31 and the item is conveyed in the conveying direction α.

[0048] FIG. 6(b) shows a state in which the leading edge of an article 104 placed on the backing sheet 102 of the packaged item 100 being conveyed has reached the installation position of the upper film hold-down member 26 in the conveying direction α. ​​The lower end of the upper film hold-down member 26 is positioned higher than the surface of the backing sheet 102, allowing the backing sheet 102 to pass between its lower end and the upstream guide plate 71 that forms the conveying path. On the other hand, the upper end of the article 104 may be positioned higher than the lower end of the upper film hold-down member 26, as shown in FIG. 6. In this case, as shown in FIG. 6(b), the article 104 contacts the upper film hold-down member 26 via the upper film F1. The upper film hold-down member 26, made of a flexible material, is pushed by the article 104 moving downstream together with the backing sheet 102 to which a conveying force is applied, causing the lower end to bend so as to displace downstream in the conveying direction, allowing the article 104 higher than the lower end to pass.

[0049] In Figure 6(c), the packaged item 100 has been inserted up to the upstream conveying roller pair 32. The upstream conveying roller pair 32 and the downstream conveying roller pair 33 hold both ends of the backing sheet 102 of the packaged item 100 that has arrived therebetween, and convey the packaged item 100 downstream.

[0050] In Figure 7(a), the rear end of the packaged item 100 passes under the upstream press member 11. The upstream press member 11 has descended from the standby position to the gripping position. The upstream conveying roller pair 32 and the downstream conveying roller pair 33 convey the packaged item 100 further downstream.

[0051] The gripping position of the upstream holding member 11 is a position where the upstream holding member 11 is pressed against the upper surface of the upstream holding member receiving portion 41. When the upstream holding member 11 is in the gripping position, the film F (F1, F2) is gripped by the upstream holding member 11 and the upstream holding member receiving portion 41 with the separator 25 sandwiched between them. In other words, the upstream holding member 11 and the upstream holding member receiving portion 41 form a gripping portion that grips the film F (F1, F2). When the film F (F1, F2) is gripped, the supply of the film F (F1, F2) from the two film rolls R (R1, R2) is stopped. In other words, the force of the packaged items 100 conveyed downstream pulling the film F (F1, F2) no longer acts upstream of the gripping portion where the upstream pressure member 11 and the upstream pressure receiving portion 41 grip the film F (F1, F2), and the film F (F1, F2) is no longer pulled out from the film roll R (R1, R2). In other words, the speed at which the film F (F1, F2) is pulled out from the film roll R (R1, R2) (hereinafter referred to as the "pulling speed") becomes zero. In other words, the upstream pressure member 11 and the upstream pressure receiving portion 41 constitute a gripping portion, and ultimately a film supply adjustment portion that stops the supply of the film F (F1, F2) (sets the pulling speed to zero). The pulling speed is the speed of the portion of the film F (F1, F2) immediately after it is pulled out from the film roll R (R1, R2). The unwinding speed can also be considered to be equal to the peripheral speed of the outer circumferential surface of the film roll R (R1, R2) that rotates as the film F (F1, F2) is unwound.

[0052] In detail, the upstream pressure member 11 reaches the gripping position after the rear end of the packaged item 100 passes below the upstream pressure member 11 but before it passes below the heater 13, and grips the film F (F1, F2) together with the upstream pressure receiving portion 41.

[0053] For example, when the inlet sensor S1 detects the rear end of the packaged item 100, the upstream hold-down member 11 may be used as a trigger to stop conveyance by the upstream conveying roller pair 32 and the downstream conveying roller pair 33 after the rear end of the packaged item 100 has passed under the upstream hold-down member 11 and before it has passed under the heater 13, and then the upstream hold-down member 11 may be lowered to the gripping position, and then conveyance by the upstream conveying roller pair 32 and the downstream conveying roller pair 33 may be resumed. Alternatively, instead of stopping conveyance by the upstream conveying roller pair 32 and the downstream conveying roller pair 33, the upstream hold-down member 11 may be used as a trigger to lower the upstream hold-down member 11 so that it reaches the gripping position after the rear end of the packaged item 100 has passed under the upstream hold-down member 11 and before it has passed under the heater 13.

[0054] With the upstream press member 11 lowered to the gripping position and the supply of the film F (F1, F2) stopped, the upstream conveying roller pair 32 and the downstream conveying roller pair 33 convey the packaged item 100 further downstream. As a result, the leading edge of the film F (F1, F2) downstream of the upstream press member 11 stretches.

[0055] In Figure 7(b), the rear end of the packaged item 100 passes below the downstream hold-down member 12. The heater support member 14 is lowered from the standby position (Figure 6), and the downstream hold-down member 12 is accordingly lowered from the standby position to the gripping position. In addition, the conveyance of the packaged item 100 by the upstream conveying roller pair 32 and the downstream conveying roller pair 33 is stopped.

[0056] The gripping position of the downstream holding member 12 is a position where the downstream holding member 12 is pressed against the upper surface of the downstream holding member receiving portion 43. When the downstream holding member 12 is in the gripping position, the film F (F1, F2) is gripped by the downstream holding member 12 and the upper surface of the downstream holding member receiving portion 43. In other words, the downstream holding member 12 and the downstream holding member receiving portion 43 constitute a gripping portion that grips the film F (F1, F2).

[0057] In detail, the downstream holding member 12 reaches the gripping position after the rear end of the packaged item 100 passes below the downstream holding member 12, and grips the film F (F1, F2) together with the downstream holding member receiving portion 43.

[0058] For example, when the heater passing sensor S2 detects the rear end of the packaged item 100, the conveyance by the upstream conveying roller pair 32 and the downstream conveying roller pair 33 is stopped at a predetermined timing, and then the downstream pressing member 12 is lowered to the gripping position.

[0059] In FIG. 7(c), the upstream holding member 11 has risen from the gripping position to the standby position. It is sufficient for the upstream holding member 11 to be able to separate from the upper surface of the upstream holding member receiving portion 41; it need not necessarily rise to the standby position. In FIG. 8(a), the upstream holding member 11 has again descended from the standby position to the gripping position. In other words, the film F (F1, F2) is temporarily released from the grip of the upstream holding member 11 and the upstream holding member receiving portion 41 (the state shown in FIG. 7(c)). This reduces the tension of the film F (F1, F2) between the upstream holding member 11 and the downstream holding member 12. This prevents poor welding in the subsequent heat welding process.

[0060] The films F (F1, F2) are pressed against the respective receiving portions (41, 43) by an upstream holding member 11 on the upstream side of the heater 13 and by a downstream holding member 12 on the downstream side of the heater 13. Furthermore, the downstream end of the separator 25, which prevents the two films F (F1, F2) from adhering to each other, is located upstream of the heater receiving portion 42 in the conveying direction, and the separator 25 is not present above the heater receiving portion 42. Therefore, the films F (F1, F2) are in close contact with each other at the position where they should be welded by the heater 13, i.e., the position below the heater 13.

[0061] 8(a), the upstream presser member 11 may be returned to a position slightly above the upper surface of the upstream presser support receiving portion 41 rather than to the gripping position. Even if the upstream presser member 11 does not press the film F (F1, F2) against the upstream presser support receiving portion 41, being in a position slightly above the upper surface of the upstream presser support receiving portion 41 can prevent the upper film F1 and the lower film F2 from separating too far. In other words, the two films F (F1, F2) are relatively closely attached. In this case, the upstream presser member 11 only needs to be returned to the gripping position before the state shown in FIG. 8(c) described below, specifically, before conveyance by the upstream conveyance roller pair 32 and the downstream conveyance roller pair 33 resumes.

[0062] In FIG. 8(b), the heater support member 14 has further descended. Because the downstream presser member 12 has already reached the gripping position when the state shown in FIG. 7(b) is reached, the downstream presser member 12 does not descend as the heater support member 14 further descends. The materials of the receiving portions (41, 42, 43) are not particularly limited, and may be, for example, materials that do not substantially deform or dent when pressed downward by at least the pressing members (11, 12). Meanwhile, the heater 13 descends as the heater support member 14 descends and reaches the welding position. The welding position is the position where the tip of the heater 13 is pressed against the upper surface of the heater receiving portion 42. In other words, as the heater support member 14 further descends from the state shown in FIG. 8(a), the upstream presser member 11 and the heater 13 move relative to each other. The heater 13 contacts the films F (F1, F2), which are in close contact with each other, and thermally welds them together. As a result, while the films F (F1, F2) downstream of the downstream press member 12 are stretched, the upstream sides of the films F (F1, F2) are welded together to form a welded part Fx (rear end welded part FxR).

[0063] 8(c), the heater support member 14 rises, and the heater 13 and downstream presser member 12 rise from the welding position and the gripping position, respectively. In this state, conveyance by the upstream conveying roller pair 32 and the downstream conveying roller pair 33 resumes, and the film F (F1, F2) is cut at the welding position. Then, the film F that has wrapped the packaged item 100 (i.e., the film F that has been cut from the continuous film F from each film roll R (R1, R2)) shrinks, and the packaged item 100 is tightly stretch-wrapped by the film F, becoming the packaged product 200.

[0064] The above is an example of the operation of the packaging machine 1. Next, in Fig. 7(a), reference will be made to the fact that the upstream presser member 11 reaches the gripping position and grips the film F (F1, F2) together with the upstream presser receiving portion 41 before the rear end of the packaged item 100 passes under the heater 13. In the packaging machine 1, the film F packaging the packaged item 100 in Fig. 6(d), i.e., the film F cut off from the continuous film (F1, F2) downstream of the welded portion Fx (rear end welded portion FxR) by the heater 13, still tends to shrink, thereby fixing the item 104 to the backing sheet 102.

[0065] In contrast, if the upstream press member 11 reaches the gripping position after the rear end of the packaged item 100 has passed under the heater 13, the film F (F1, F2) downstream of the heater 13 is already long enough at that point (i.e., before stretching) to loosely wrap the packaged item 100. Naturally, even if the film F is released and shrinks after stretching, it will not become shorter than the length before stretching. Therefore, in this case, the film F wrapping the packaged item 100 cannot secure the item 104 to the backing sheet 102.

[0066] Therefore, it is necessary to have the upstream pressure member 11 reach the gripping position and grip the film F (F1, F2) together with the upstream pressure receiving portion 41 before the rear end of the packaged item 100 passes under the heater 13.

[0067] However, even if the upstream presser member 11 reaches the gripping position before the rear end of the packaged item 100 passes under the heater 13, if the distance "L3" (see FIG. 7(a)) in the conveying direction from the rear end of the packaged item 100 to the heater 13 at that time is short, the packaged item 100 may still only be loosely wrapped. Specifically, even if the stretched film shrinks, it may not return to its original length. If the length of the part longer than the original length (hereinafter referred to as the "stretched part") is longer than "L3," the packaged item 100 may only be loosely wrapped. Therefore, "L3" must be longer than the length of the stretched part, and the longer "L3" is, the tighter the packaging. To achieve the length of "L3," "L1" needs to have a certain length. On the other hand, the length of "L2" does not affect this, and it is preferable that it be as short as possible to configure the device compactly.

[0068] Furthermore, as is clear from the fact that the packaged items 100 are packaged using the elasticity of the film, the distance "L2" in the conveying direction from the heater 13 to the downstream hold-down member 12, the distance "L5" in the conveying direction from the leading edge of the packaged items 100 in Fig. 7(b) to the upstream hold-down member 11, and the distance "L4" in the conveying direction from the trailing edge of the packaged items 100 in Fig. 7(b) to the downstream hold-down member 12 affect whether the packaged items 100 are securely packaged so that the position of the articles 104 does not shift relative to the backing sheet 102 when vibrations or impacts are applied to the packaged items 100. These distances "L2", "L4", and "L5" may be determined to appropriate values ​​based on the elasticity of the film F that constitutes the film F (F1, F2) based on experiments, etc.

[0069] The upstream pressure member 11, the downstream pressure member 12, and the heater 13 may be movable separately in the conveying direction. In this case, the distances "L2," "L4," and "L5" can be changed. For example, when changing the film F (F1, F2) to one with different elasticity or when changing the length of the backing sheet 102 in the conveying direction, the distances "L2," "L4," and "L5" can be adjusted so that the packaged item 100 is securely packaged.

[0070] According to one example of the operation of the packaging machine 1 described above, the packaged item 100 can be stretch-packaged with a relatively simple and easy operation in which the packaged item 100 is conveyed downstream while the film F (F1, F2) is held on the upstream side of the packaged item 100, stretching the film F (F1, F2), and then welding the film F (F1, F2) in that state, without having to move the packaged item 100 upstream (reverse running) or rewind the film F (F1, F2) as in the configuration described in Patent Document 2, and as a result, the packaged item 100 can be stretch-packaged with a relatively simple and easy operation in which the film F (F1, F2) is conveyed downstream while the film F (F1, F2) is held on the upstream side of the packaged item 100, stretching the film F (F1, F2), and then welding the film F (F1, F2) in that state, thereby reducing the time required for packaging.

[0071] The above description of the operation of the packaging machine 1 is an example, and it will be understood by those skilled in the art that various modifications are possible in the combination of each component and each processing process, and that packaging devices that perform such modified operations are also within the scope of the present invention. These modifications will be described below.

[0072] <Variation 1> In the example of the operation of the packaging machine 1 described above, the upstream presser member 11 and the upstream presser receiving portion 41 constitute a gripping portion and therefore a film supply adjustment portion, but this is not limited to this. For example, the packaging machine 1 may be equipped with a brake mechanism that applies a brake to prevent the film roll R (R1, R2) from rotating and releases the brake to allow it to rotate. In this case, applying the brake to prevent the film roll R (R1, R2) from rotating stops the supply of film F (F1, F2) from the film roll R (R1, R2). In other words, the brake mechanism constitutes the film supply adjustment portion.

[0073] <Variation 2> In the above-described exemplary operation of the packaging machine 1 and the above-described first modification, the film supply adjustment unit stops the film supply, in other words, sets the film unwinding speed to zero. However, this is not limited to this. The film supply adjustment unit can simply reduce the unwinding speed without setting it to zero. Specifically, the unwinding speed can be slower than the speed at which the packaged items 100 move downstream. If the unwinding speed is slower than the speed at which the packaged items 100 move downstream, the two films F (F1, F2) will stretch, achieving the same effect as the above-described exemplary operation of the packaging machine 1. For example, if the upstream pressure member 11 and the upstream pressure receiving portion 41 constitute the film supply adjustment unit, the unwinding speed can be slowed by weakening the force pressing the upstream pressure member 11 against the upstream pressure receiving portion 41. For example, if the brake mechanism described in the first modification constitutes the film supply adjustment unit, the brake mechanism can apply a weaker brake to slow the unwinding speed.

[0074] Next, the separator 25 provided in the packaging machine 1 of this embodiment will be described. In the packaging machine 1, as described above, the films F (F1, F2) are in close contact with each other at the positions to be welded by the heater 13. However, if the films F (F1, F2) are in close contact with each other and form a close contact area upstream (toward the film roll R) of the leading edge welded portion FxF (see FIG. 8(c)), which is the continuous film side of the welded portion Fx after welding and cutting, the following problems may occur.

[0075] That is, if a contact area between the films F is formed upstream of the leading edge weld FxF, the leading edge of the inserted packaged item 100 will not reach the leading edge weld FxF but will strike the upstream end of the contact area formed further upstream. When the leading edge of the packaged item 100 is then conveyed downstream, the contact area of ​​the film F is pushed downstream, and the films F (F1, F2) are pulled out from the two film rolls R (R1, R2). If the packaging process described with reference to FIGS. 6 to 8 is performed in a state in which the contact area upstream of the weld Fx is pushed instead of the leading edge of the packaged item 100, the film F that has wrapped the packaged item 100 will shrink while the contact area remains formed, resulting in a packaged product 200 in which the packaged item 100 is stretch-packaged by the film F. The contact area of ​​the packaged product 200 thus created is merely held together by the forces of the films F trying to contact each other; unlike the weld Fx, the films F are not fixedly stuck together. Therefore, if the adhesion of the adhesion area is released for some reason, the film F that has been securing the item 104 to the backing sheet 102 will loosen due to the shrinking force, and the shrinking force acting on the item 104 and the backing sheet 102 will become smaller, causing the item 104 to be released from its attachment to the backing sheet 102, which could make the stretch film packaging meaningless.

[0076] To address this problem, the packaging machine 1 of this embodiment is equipped with the separator 25, which limits the range in which the upper film F1 and the lower film F2 can be in close contact upstream of the position where they are to be welded by the heater 13, and can prevent the packaging process from being performed in a state in which a close contact area remains formed between the leading edge welded part FxF and the leading edge of the packaged item 100. This prevents the film F, which has been in close contact with the backing sheet 102 of the packaging product 200 and the item 104, from loosening due to the formation of a close contact area during the packaging process, and prevents the problem of the item 104 being released from the backing sheet 102 of the packaging product 200.

[0077] 3 and 4, the packaging machine 1 of this embodiment is arranged so that the downstream end of the separator 25 is close to the upstream end of the heater receiving portion 42. This further prevents the upper film F1 and the lower film F2 from coming into close contact with each other upstream of the position where they are to be welded by the heater 13, and prevents the film F of the packaged product 200 from loosening, causing the article 104 to be released from the backing sheet 102 of the packaged product 200.

[0078] Patent Document 2 describes a packaging device in which the film is unwound after welding, leaving the two welded films in a vertically stretched state, and the inserted packaged item moves horizontally, perpendicular to the vertically stretched film, pushing the film downstream. With this type of packaging device, even if a tightly sealed area is formed upstream of the welding part, pulling the two films in the vertical direction to the point where this tightly sealed area disappears can potentially prevent the occurrence of a problem in which the article and backing sheet become unfastened due to the formation of the tightly sealed area.

[0079] However, the more the sealed area disappears after welding, the longer it takes to rewind the film, which increases the time until the next packaged item can be inserted, reducing productivity. Furthermore, the film rewinding mechanism leads to an increase in the size of the device. In contrast, by simply arranging the packaging machine 1 and separator 25 of this embodiment, the formation of sealed areas can be suppressed and the work of rewinding the film is unnecessary, preventing a decrease in productivity and an increase in the size of the device.

[0080] In this embodiment, the separator 25 is made of "Clarino (registered trademark) #3910-0403 t=1.0" manufactured by Kuraray Co., Ltd., but is not limited thereto. Any material may be used as long as it does not impede the movement of the contacting film F and prevents the two films F from adhering to each other when positioned between the two films F (F1, F2). In a configuration in which the separator 25 is positioned so as to straddle the upstream press-hold receiving portion 41 in the conveyance direction as shown in FIGS. 3, 4, and 6 to 8, the separator 25 desirably has properties (such as a coefficient of friction with the film F) that prevent the film F from moving downstream even when the film F (F1, F2) is pulled downstream when the film F is sandwiched between the upstream press-holding member 11 and the upstream press-hold receiving portion 41 together with the separator 25. Furthermore, the separator 25 desirably has properties such as flexibility that prevents deformation even when repeatedly sandwiched between the upstream press-holding member 11 and the upstream press-hold receiving portion 41.

[0081] Furthermore, in a configuration without separator 25, when the rear end welded portion FxR and the front end welded portion FxF are separated after welding using heater 13, a problem occurs in that film F curls up, rolling up the front end welded portion FxF inward. By disposing separator 25, which is more rigid than film F, it is possible to prevent film F from curling up.

[0082] Next, the upper film holding member 26 provided in the packaging machine 1 of this embodiment will be described. The packaging machine 1 can package items 104 of various heights placed on a backing sheet 102. Therefore, there is no guide member for guiding the upper film F1 at a position lower than the maximum height of the insertable item 104, and in the standby state, a wide space is formed in the height direction in the conveying path for the packaged items 100. Therefore, in the standby state in a configuration without the upper film holding member 26, a wide space exists above the upstream guide plate 71 that forms the conveying path in which the upper film F1 can move, allowing taller items 104 to pass through. If the movement path of the upper film F1 becomes unstable and the upper film F1 enters this space, the surfaces of the upper film F1 will adhere to each other, making it difficult to peel off, and there is a risk that the upper film F1 will become clogged inside the device.

[0083] To address this problem, the packaging machine 1 is provided with an upper film hold-down member 26, which restricts the upward movement of the upper film F1, preventing the upper film F1 from getting stuck inside the device. Furthermore, the upper film hold-down member 26 is made of a flexible material, and even if a packaged item 100 including a tall item 104 is inserted, the upper film hold-down member 26 deforms to avoid the item 104. Therefore, the packaging machine 1 can package packaged items 100 including items 104 that are somewhat tall, while preventing the upper film F1 from getting stuck.

[0084] Furthermore, as a result of extensive research by the inventors, it was found that in a packaging machine 1 in which the film F is held down by the upstream holding member 11 and welded with the heater 13, poor welding could occur in a configuration that does not include an upper film holding member 26. FIG. 9 is a comparative diagram of a configuration with and without an upper film hold-down member 26. FIG. 9(a) is an explanatory diagram of a packaging machine 1 of this embodiment equipped with an upper film hold-down member 26, in which conveyance by the upstream conveying roller pair 32 and the downstream conveying roller pair 33 has been stopped before the upstream hold-down member 11 is lowered as shown in FIG. 7(a). FIG. 9(b) is an explanatory diagram of a packaging machine 1 of a comparative example not equipped with an upper film hold-down member 26, showing the timing corresponding to FIG. 9(a) of the above-described embodiment. FIG. 9(c) is an explanatory diagram of a packaging machine 1 of the comparative example, in which the upstream hold-down member 11 has been lowered from the state shown in FIG. 9(b), showing the timing corresponding to FIG. 7(a) of the above-described embodiment.

[0085] In the packaging machine 1 of the comparative example shown in Figures 9(b) and 9(c), as shown in Figure 9(c), when the upstream pressure member 11 was lowered, the widthwise end of the upper film F1 was sometimes rolled inward, and the end of the upper film was folded inward and held in an overlapping state by the upstream pressure member 11 and the upstream pressure receiving portion 41. In this state, if the packaged item 100 was conveyed further downstream, the film F was stretched, and the film F was held by the downstream pressure member 12 and the downstream pressure receiving portion 43. Then, when the heater 13 was lowered to the welding position, welding was performed with the end of the upper film F1 still overlapping, which could result in poor welding in the overlapping area or a deterioration in the visual quality due to the overlapping. This is thought to be due to the following reasons.

[0086] Specifically, in the packaging machine 1 of the comparative example, if there is no member downstream of the upper film second guide 53, which is a guide member for the upper film F1 positioned above the space through which the article 104 can pass, when the conveyance of the packaged item 100 is stopped after the rear end of the packaged item 100 passes under the upstream press-on member 11 (the state shown in FIG. 9(b)), even though the packaged item 100 stops, the upper film F1 is subjected to a force that tries to move downstream due to inertia. Since there is no member to inhibit this downstream movement of the upper film F1, excess upper film F1 may be unwound. This causes slack in the upper film F1 around the lower portion of the upstream press-on member 11, making it more susceptible to deformation, such as the widthwise edge being curled inward, than when tension is applied. When the upstream press-on member 11 is lowered to the clamping position in this deformed state (the state shown in FIG. 9(c)), the edge of the upper film is folded inward and overlapped, which is thought to result in poor welding and reduced quality.

[0087] To address this issue, the packaging machine 1 of this embodiment is provided with the upper film holding member 26, which prevents welding of the widthwise ends of the upper film F1 in an overlapping state. This is believed to be due to the following reasons. That is, when the conveyance of the packaged item 100 is stopped after the rear end of the packaged item 100 passes under the upstream holding member 11 (the state shown in FIG. 9(a)), even if a force acts on the upper film F1 to move downstream due to inertia, the lower end of the upper film holding member 26 presses the upper film F1 downward, preventing the upper film F1 from moving downstream. This prevents excess upper film F1 from being unwound, prevents slack from occurring in the upper film F1, and makes it less likely that deformation will occur in which the widthwise ends of the upper film F1 are rolled inward. Furthermore, since it is possible to prevent the ends of the upper film F1 from being folded inward and overlapping, it is thought that it is possible to prevent welding of the widthwise ends of the upper film F1 in an overlapping state.

[0088] In this embodiment, when the upper film F1 is not attached, the upper film holding member 26 does not contact the conveying surface of the conveying path (the upper surface of the separator 25, the upper surface of the upstream guide plate 71), and the distance from the lower end of the upper film holding member 26 to the conveying surface is 20 mm. As shown in Figure 4, the width of the separator 25 narrows near the entrance roller pair 31, and if the lower end of the upper film holding member 26 is arranged to contact the conveying surface, the lower surface of the upper film F1 pressed downward by the upper film holding member 26 and the upper surface of the lower film F2 will come into close contact outside the narrowed portion of the separator 25, which could cause problems due to the films F sticking together. Furthermore, if the gap between the lower end of the upper film holding member 26 and the conveying surface is larger than the height of the packaged item 100, when the conveyance of the packaged item 100 is stopped, the upper film F1 may float above the upper surface of the packaged item 100, as in the state shown in Figure 9(b), or the force with which the upper film holding member 26 presses the upper film F1 downward may be insufficient, making it prone to loosening due to inertial force. If the configuration can prevent these problems from occurring, the lower end of the upper film holding member 26 may be arranged so that it is in contact with the conveying surface, or the distance from the lower end of the upper film holding member 26 to the conveying surface may be greater than 20 mm.

[0089] In this embodiment, the upper film holding member 26 is made of "Clarino (registered trademark) #3910-0403 t=1.0" manufactured by Kuraray Co., Ltd. However, the material is not limited to this as long as it allows the passage of the article 104 while preventing the upper film F1 from moving upward or from being unwound excessively. Furthermore, if a polyester film with a smooth surface such as Mylar (registered trademark) is used as the upper film holding member 26, the polyester film may adhere to the upper film F1 and inhibit the upper film F1 from moving downstream. Therefore, a suede-like material with a raised surface may be preferable. The shape of the upper film holding member 26 may be a single plate-like member extending in the width direction, or may be a shape similar to a noren curtain, with at least the lower end divided into multiple sections to easily deform along the surface of the passing article 104. Furthermore, the upper film hold-down member 26 is not limited to being flexible, and may be any member that is located upstream of the upstream hold-down member 11 and that can restrict the movement path of the upper film F1, thereby preventing slack from occurring in the upper film F1 around the lower portion of the upstream hold-down member 11. For example, it may be a plate-like member that can rotate about an upstream rotation axis, and that holds down the upper film F1 during standby, but rotates so that its lower end moves upward when pushed by the packaged items 100 during packaging processing, allowing the packaged items 100 to pass through. Furthermore, the member whose lower end moves upward when pushed by the packaged items 100 may be a roller member whose roller rotation axis moves upward when pushed by the packaged items 100, such as a roller rotation axis support member that rotates about a rotation axis when pushed by the packaged items 100.

[0090] In the above-described embodiment, the joining means for joining the upper film F1, which is the first packaging material, and the lower film F2, which is the second packaging material, is a heater, which is a heat welding means, but the joining method is not limited to heat welding. Other joining methods, such as pressure bonding or ultrasonic welding, may be used as long as they join the first packaging material and the second packaging material.

[0091] The above description is merely an example, and each of the following aspects provides unique effects.

[0092] [Aspect 1] The first embodiment includes a conveying means such as an upstream conveying roller pair 32 and a downstream conveying roller pair 33 that convey an item to be packaged such as an item 100 to be packaged, a first packaging material supplying means such as an upper film roll R1 that supplies a first packaging material such as an upper film F1 of two strip-shaped packaging materials such as films F that package the item to be packaged, and a second packaging material supplying means such as a lower film roll R2 that supplies a second packaging material such as a lower film F2, and a joining means such as a heater 13 that joins the first packaging material and the second packaging material to form a joining region such as a welded portion Fx that extends in a width direction (X-axis direction in the drawing) perpendicular to a conveying direction such as a conveying direction α by the conveying means ... As the front ends of the packaged items collide and the packaged items move further downstream in the conveying direction, the first and second packaging materials are pushed by the packaged items and supplied from the first and second packaging material supply means while wrapping around the packaged items. After the rear end of the packaged items in the conveying direction passes the joining position of the joining means (heater receiving portion 42, etc.), the joining means joins the first and second packaging materials together, thereby wrapping the first and second packaging materials around the packaged items for packaging. In a packaging device such as packaging machine 1, which wraps the first and second packaging materials around the packaged items to package them, the packaging device is equipped with a packaging material adhesion prevention member such as plate-shaped separator 25 that is positioned between the first and second packaging materials upstream in the conveying direction from the joining position and prevents the first and second packaging materials from coming into close contact.

[0093] According to aspect 1, by providing a packaging material adhesion prevention member, it is possible to prevent the first packaging material and the second packaging material from coming into contact with each other and prevent the formation of an adhesion area, which has the excellent effect of preventing defects caused by the creation of a finished product with an adhesion area still formed.

[0094] [Aspect 2] In the packaging device of the first embodiment, the packaging device is provided with upstream pressure member 11 and upstream pressure receiving portion 41 and other upstream packaging material clamping means that are located upstream of the joining position in the conveying path of the packaged items in the conveying direction and are changeable between an open state such as a waiting position through which the first packaging material and the second packaging material can pass, and a clamping state such as a gripping position in which the first packaging material and the second packaging material are clamped and the first packaging material and the second packaging material upstream of the clamping position are prevented from moving downstream of the clamping position, and the upstream end of the packaging material adhesion prevention member in the conveying direction is fixed to a conveying path forming member such as upstream guide plate 71 that forms the conveying path (fixed via the entrance underside guide 21 and the device housing), and the packaging material adhesion prevention member is arranged along the conveying path from this upstream end in the conveying direction to the downstream side in the conveying direction, and the downstream end of the packaging material adhesion prevention member in the conveying direction is located downstream of the clamping position by the upstream packaging material clamping means and upstream of the joining position by the joining means.

[0095] According to aspect 2, since the downstream end of the packaging material adhesion prevention member is downstream of the clamping position by the upstream packaging material clamping means, it is possible to prevent the first packaging material and the second packaging material from coming into close contact downstream of the clamping position of the upstream packaging material clamping means, where clamping by the upstream packaging material clamping means makes it easier for the first packaging material and the second packaging material to come into close contact.

[0096] Aspect 3 A third aspect of the present invention relates to a packaging device according to the second aspect, which is provided with a downstream pressing member 12 or other downstream packaging material clamping means that is located downstream in the conveying direction of the joining position on the conveying path of the packaged items and that is changeable between an open state such as a waiting position through which the first packaging material and the second packaging material can pass, and a clamping state such as a gripping position that clamps the first packaging material and the second packaging material and prevents the first packaging material and the second packaging material upstream of the clamping position from moving downstream of the clamping position, and after the upstream end of the packaged items in the conveying direction passes the clamping position of the upstream packaging material clamping means, the upstream packaging material clamping means clamps the first packaging material and the second packaging material. This packaging device sets the material clamping means in a clamping state, sets the upstream packaging material clamping means in a clamping state, and then further transports the package so that the upstream end of the package in the transport direction passes the clamping position of the downstream packaging material clamping means, then sets the downstream packaging material clamping means in a clamping state, and then performs a joining process such as welding to join the first packaging material and the second packaging material using a joining means, and a cutting process to cut the first packaging material and the second packaging material so that joining areas (rear end welded portion FxR and front end welded portion FxF) are formed upstream and downstream of the cutting position.

[0097] According to aspect 3, after the upstream packaging material clamping means is set to the clamping state, the packaged item is further conveyed and passes the clamping position of the downstream packaging material clamping means, and then the downstream packaging material clamping means is set to the clamping state and cut, so that the joining process and cutting process can be performed in a stretched state of the packaging material, and the packaging material can be wrapped around the packaged item by the force of the packaging material trying to contract as it returns to its original state from the stretched state. Stretching two packaging materials while they are overlapping can easily form a tightly sealed area, but the provision of a packaging material adhesion prevention member can prevent the formation of a tightly sealed area.

[0098] Aspect 4 The packaging device of aspect 4 is a packaging device characterized in that, in the packaging device of aspect 3, after the downstream packaging material clamping means is set to a clamping state and the upstream packaging material clamping means is set to an open state, the joining process and the cutting process are performed.

[0099] According to the fourth aspect, it is possible to reduce the tension (tensile force) in the portion of the packaging material where joining and cutting processes are performed, thereby suppressing the occurrence of poor joining in the subsequent joining process.

[0100] Aspect 5 The packaging device of aspect 5 is a packaging device according to any one of aspects 1 to 4, in which the horizontal position of the packaged items is displaced as the packaged items move in the conveying direction, the first packaging material is supplied from above to the conveying path of the packaged items, the second packaging material is supplied from below to the conveying path of the packaged items, and the packaging material adhesion prevention member is located above the moving path of the second packaging material and below the moving path of the packaged items.

[0101] According to aspect 5, by disposing a packaging material adhesion prevention member between the movement path of the second packaging material and the movement path of the packaged items, the first packaging material and the second packaging material are joined downstream of the downstream end of the packaging material adhesion prevention member, and a configuration can be realized in which the packaging material is pushed downstream in the conveying direction by the packaged items moving downstream in the conveying direction. In the packaging machine 1 of the embodiment, the conveying direction of the packaged items is the Y-axis direction parallel to the horizontal direction, but is not limited to this, and the conveying direction may be inclined with respect to the horizontal direction.

[0102] Aspect 6 The packaging device of embodiment 6 is the packaging device of embodiment 5, and is provided with a packaging material movement path displacement suppression member such as an upper film pressing member 26 that is positioned upstream in the conveying direction from the joining position, is made of a plate-shaped flexible material extending in the vertical direction with its upper part fixed to the device housing, and whose lower end side comes into contact with the first packaging material, thereby suppressing upward displacement of the movement path of the first packaging material toward the conveying path of the packaged item, and is configured so that when the packaged item moving in the conveying direction comes into contact with the packaging material movement path displacement suppression member via the first packaging material, the packaging material movement path displacement suppression member deforms, allowing the packaged item to pass through.

[0103] According to the sixth aspect, it is possible to stabilize the movement path of the first packaging material, thereby preventing the first packaging material from becoming clogged, and to package items including articles of a certain height.

[0104] Furthermore, in a configuration without the separator 25 and the upper film hold-down member 26, there is no member that guides the upper film F1 downstream of the upper film second guide 53 in the movement path of the upper film F1, and there is no member that guides the lower film F2 downstream of the lower film guide 55 in the movement path of the lower film F2. Therefore, in the standby state, there is no member that determines the position of the film F (F1, F2) between the upper film second guide 53 and the lower film guide 55, including the welded portion Fx, and the movement of the film F is unstable, which may cause the films F to stick together or twist due to bending, resulting in a transport failure such as internal jamming or folding of the film F. In contrast, in a packaging machine 1 that includes the separator 25 and the upper film hold-down member 26, as shown in Figures 3 and 6, the position of the film F (F1, F2) between the upper film second guide 53 and the lower film guide 55, including the welded portion Fx, is guided by the separator 25 and the upper film hold-down member 26, thereby stabilizing the movement of the film F and preventing transport failure.

[0105] Aspect 7 Aspect 7 includes a conveying means such as an upstream conveying roller pair 32 and a downstream conveying roller pair 33 that convey an item to be packaged such as an item 100 to be packaged, a first packaging material supplying means such as an upper film roll R1 that supplies a first packaging material such as an upper film F1 of two strip-shaped packaging materials such as films F that package the item to be packaged, and a second packaging material supplying means such as a lower film roll R2 that supplies a second packaging material such as a lower film F2, and a joining means such as a heater 13 that joins the first packaging material and the second packaging material to form a joining region such as a welded part Fx that extends in a width direction (X-axis direction in the drawing) perpendicular to a conveying direction such as a conveying direction α by the conveying means, and when the leading ends of the packaged item in the conveying direction abut against the first packaging material and the second packaging material whose leading ends have been joined to each other, Furthermore, as the packaged item moves downstream in the conveying direction, the first and second packaging materials pressed by the packaged item are supplied from the first and second packaging material supply means while wrapping around the packaged item, and after the trailing end of the packaged item in the conveying direction passes the joining position of the joining means (heater receiving portion 42, etc.), the joining means joins the first and second packaging materials together. This relates to a packaging material adhesion prevention member such as a plate-shaped separator 25 that can be attached to a packaging device such as a packaging machine 1 that wraps the first and second packaging materials around the packaged item to package it, and is attached between the first and second packaging materials upstream in the conveying direction from the joining position of the packaging device to prevent the first and second packaging materials from coming into close contact.

[0106] By attaching the packaging material adhesion prevention member of aspect 7 to a packaging device, it is possible to prevent the first packaging material and the second packaging material from coming into contact with each other, and to prevent the formation of an adhesion area, which has the excellent effect of preventing defects caused by the creation of a finished product with an adhesion area still formed.

[0107] Aspect 8 Aspect 8 is a packaging device that includes a conveying section such as an upstream conveying roller pair 32 and a downstream conveying roller pair 33 that convey packaged items such as packaged item 100; a film supply adjustment section such as an upstream pressure member 11 that slows the pull-out speed, at which two films F such as films F (F1, F2) whose leading ends are welded to each other and which are pulled out from two film rolls such as an upper film roll R1 and a lower film roll R2 as the packaged item inserted between them moves downstream, compared to the speed at which the packaged item moves downstream; and a heater such as heater 13 that heat-welds the two films F together when the rear end of the packaged item being conveyed by the conveying section passes a heating position such as below the heater, and the film supply adjustment section slows the pull-out speed compared to the movement speed of the packaged item before the rear end of the packaged item passes the heating position of the heater.

[0108] According to the eighth aspect, the item to be packaged can be packaged with stretch film without conveying the item in the reverse direction or rewinding the film, thereby reducing the time required for packaging.

[0109] Aspect 9 Aspect 9 is a packaging device characterized in that, in the packaging device of aspect 8, the film supply adjustment unit is composed of a first gripping unit such as a gripping unit composed of an upstream pressure member 11 and an upstream pressure receiving unit 41, etc., capable of gripping two sheets of film F upstream of the heater 13, and by the first gripping unit gripping the two sheets of film F, the pulling speed of the two sheets of film F is made slower than the moving speed of the packaged item.

[0110] Aspect 10 In aspect 10, the packaging device of aspect 9 is provided with a packaging material loosening prevention member such as an upper film holding member 26 that is positioned upstream of the first gripping portion in the conveying direction and whose lower end contacts the first packaging material to prevent loosening of the first packaging material heading toward the conveying path of the packaged item, and when the packaged item moving in the conveying direction comes into contact with the packaging material loosening prevention member via the first packaging material, the lower end of the packaging material loosening prevention member is displaced upward, allowing the packaged item to pass through.

[0111] Aspect 11 An eleventh aspect of the present invention is a packaging device in which the packaging material loosening prevention member is made of a plate-like flexible material that extends in the vertical direction and whose upper portion is fixed to the device housing.

[0112] Aspect 12 Aspect 12 is a packaging device characterized in that, in any of aspects 9 to 11, the film supply adjustment section includes a second gripping section such as a gripping section composed of a downstream pressure member 12 and a downstream pressure receiving section 43 that can grip two sheets of film F downstream of the heater 13, and the second gripping section grips the two sheets of film F after the first gripping section grips the two sheets of film F and before they are thermally welded by the heater.

[0113] Aspect 13 Aspect 13 is a packaging device characterized in that, in the packaging device of aspect 12, the distance "L1" in the conveying direction from the first gripping portion to the heater 13 is longer than the distance "L2" in the conveying direction from the heater 13 to the second gripping portion.

[0114] Aspect 14 Aspect 14 is a packaging device characterized in that, in the packaging device of aspect 12 or aspect 13, after the second gripping portion grips the two films F, the first gripping portion temporarily releases the grip of the two films F and then grips them again before the heater 13 heat-seals them.

[0115] Aspect 15 Aspect 15 is a packaging device characterized in that, in any of aspects 8 to 14, the two films F are narrower than the packaged item, and the conveying means such as the upstream conveying roller pair 32 and the downstream conveying roller pair 33 clamp and convey the packaged item 100 on the outer side of the two films F in the width direction.

[0116] Aspect 16 Aspect 16 is a packaging device according to any one of aspects 8 to 15, characterized in that the film supply adjustment unit sets the withdrawal speed to zero, making the withdrawal speed slower than the movement speed of the packaged item. [Explanation of symbols]

[0117] 1: Packaging machine 11: Upstream holding member 12: Downstream holding member 13: Heater 14: Heater support member 15: Downstream presser support member 25: Separator 26: Upper film holding member 31: Entrance roller pair 32: Upstream conveying roller pair 33: downstream conveying roller pair 34: Exit roller pair 41: Upstream presser receiving part 42: Heater receiving part 43: Downstream presser foot 100: Packaged item 102: Mount 104: Goods 200: Packaging deliverables F1: Top film F2: Lower film Fx: Welded part FxF: Tip side weld part FxR: Rear end side welding part R: Film roll R1: Upper film roll R2: Lower film roll

Claims

1. A conveying means for conveying the packaged item; a first packaging material supply means for supplying one of two strip-shaped packaging materials for packaging the packaged items, a first packaging material, and a second packaging material supply means for supplying the other of the two strip-shaped packaging materials, a second packaging material; a joining means for joining the first packaging material and the second packaging material together so as to form a joining region extending in a width direction perpendicular to a conveying direction by the conveying means, The leading ends of the packaged items in the conveying direction hit the first packaging material and the second packaging material whose leading ends are joined to each other, and the packaged items move further downstream in the conveying direction, so that the first packaging material and the second packaging material pressed by the packaged items are supplied from the first packaging material supply means and the second packaging material supply means while wrapping around the packaged items, In a packaging device that wraps the first packaging material and the second packaging material around the packaged item to package it, after the rear end of the packaged item in the conveying direction passes a joining position of the joining means, the joining means joins the first packaging material and the second packaging material together, A packaging device including a plate-shaped packaging material adhesion prevention member positioned between the first packaging material and the second packaging material upstream of the joining position in the conveying direction, which prevents the first packaging material and the second packaging material from coming into close contact with each other.

2. The packaging device of claim 1, an upstream packaging material clamping means that is located upstream of the joining position in the conveying direction of the conveying path of the packaged items and that can be changed between an open state where the first packaging material and the second packaging material can pass therebetween and a clamping state where the first packaging material and the second packaging material are clamped together to prevent the first packaging material and the second packaging material that are upstream of the clamping position from moving downstream of the clamping position; The packaging device has an upstream end in the conveying direction of the packaging material adhesion prevention member fixed to a conveying path forming member that forms the conveying path, and the packaging material adhesion prevention member is arranged along the conveying path from this upstream end in the conveying direction toward the downstream side in the conveying direction, and its downstream end in the conveying direction is located downstream of the clamping position by the upstream packaging material clamping means and upstream of the joining position by the joining means.

3. The packaging device of claim 2, a downstream packaging material clamping means that is located downstream of the joining position in the conveying direction of the conveying path of the packaged items and that can be changed between an open state where the first packaging material and the second packaging material can pass therebetween and a clamped state where the first packaging material and the second packaging material are clamped together to prevent the first packaging material and the second packaging material that are upstream of the clamping position from moving downstream of the clamping position; After the upstream end of the package in the conveying direction passes the clamping position of the upstream packaging material clamping means, the upstream packaging material clamping means is placed in a clamping state, After the upstream packaging material clamping means is set to the clamping state, the package is further conveyed, and the upstream end of the package in the conveying direction passes the clamping position of the downstream packaging material clamping means. After that, the downstream packaging material clamping means is set to the clamping state, A packaging device that performs a joining process to join the first packaging material and the second packaging material using the joining means after placing the downstream packaging material clamping means in a clamping state, and a cutting process to cut the first packaging material and the second packaging material so that the joining area is formed upstream and downstream of the cutting position.

4. The packaging device of claim 3, A packaging device characterized in that after the downstream packaging material clamping means is set to a clamping state, the upstream packaging material clamping means is set to an open state, and then the joining process and the cutting process are carried out.

5. The packaging device according to any one of claims 1 to 4, The packaged items are displaced in the horizontal direction by moving in the conveying direction (basically moving horizontally, but also including diagonal movement). The first packaging material is supplied from above to a conveying path of the packaged item, The second packaging material is supplied from below to a conveying path of the packaged item, A packaging device in which the packaging material adhesion prevention member is located above the movement path of the second packaging material and below the movement path of the packaged item.

6. The packaging device of claim 5, a packaging material movement path displacement suppression member that is disposed upstream of the joining position in the conveying direction, is made of a plate-shaped flexible material that extends in the vertical direction and has an upper portion fixed to the device housing, and has a lower end side that contacts the first packaging material, thereby suppressing upward displacement of the movement path of the first packaging material that is directed toward the conveying path of the packaged item; A packaging device configured such that when the packaged item moving in the conveying direction comes into contact with the packaging material movement path displacement suppression member via the first packaging material, the packaging material movement path displacement suppression member deforms, allowing the packaged item to pass through.

7. A conveying means for conveying the packaged item; a first packaging material supply means for supplying one of two strip-shaped packaging materials for packaging the packaged items, a first packaging material, and a second packaging material supply means for supplying the other of the two strip-shaped packaging materials, a second packaging material; a joining means for joining the first packaging material and the second packaging material together so as to form a joining region extending in a width direction perpendicular to a conveying direction by the conveying means, The leading ends of the packaged items in the conveying direction hit the first packaging material and the second packaging material whose leading ends are joined to each other, and the packaged items move further downstream in the conveying direction, so that the first packaging material and the second packaging material pressed by the packaged items are supplied from the first packaging material supply means and the second packaging material supply means while wrapping around the packaged items, The device can be attached to a packaging device that wraps the first packaging material and the second packaging material around the packaged item to package it, by having the joining means join the first packaging material and the second packaging material together after the rear end of the packaged item in the conveyance direction passes a joining position of the joining means, A plate-shaped packaging material adhesion prevention member that is attached between the first packaging material and the second packaging material upstream of the joining position of the packaging device in the conveying direction to prevent the first packaging material and the second packaging material from coming into close contact with each other.

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