Packaging methods and packaging machines

Abstract

The present invention provides a packaging machine and packaging method that reliably and effectively removes air from packaging materials or packaging bags, enabling tight packaging. [Solution] The system includes a bag-making means that forms a bag into a cylindrical shape by wrapping a continuously supplied strip-shaped packaging material YA1 around a transported article XA1, and a lateral sealing means 13 that laterally seals and cuts the packaging material YA1 in the width direction on the upstream and downstream sides of the transport direction T of the article XA1. A degassing means 75 is provided downstream of the lateral sealing means 13 in the transport direction T to remove air from the upstream side of the article XA1 contained within the packaging material YA1.

Description

Technical Field

[0001] The present invention relates to a packaging machine and a packaging method for packaging articles with a continuously supplied packaging material.

Background Art

[0002] In a packaging line for packaging articles such as foods and daily necessities, the articles are successively supplied to a packaging machine and individually packaged with a packaging material such as a film. Specifically, as the articles are successively supplied to the packaging machine, a packaging material such as a film is continuously supplied and formed into a tubular bag. In the process of forming the packaging material into a tubular bag, the articles are successively supplied, and then the both side edges of the packaging material are center-sealed. Then, a horizontal seal (cross seal) and a cut are performed in the width direction of the packaging material at a predetermined pitch, and each article is packaged. At the time of the horizontal seal, air may be evacuated simultaneously. For example, it is known to strike the downstream end while fixing the packaging material from above to evacuate the excess air inside (see Patent Document 1).

[0003] Also, a technique capable of effectively evacuating the air that has entered around the side of the article inside the packaging material is also known (for example, see Patent Document 2).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, conventional equipment all had the problem of not being able to adequately remove air from inside the packaging material. In particular, when sealing and cutting while forming a gusset with a horizontal sealing device, air would accumulate in the gusset area and be difficult to remove. As a result, there was a problem in that tight packaging that conformed to the shape of the item (where the item and packaging material were in close contact) could not be achieved. This problem is not limited to cases where the packaging material is formed into a cylindrical bag while enclosing the item, but can be common when the item is already contained within the packaging bag.

[0006] This invention has been made in view of the above problems, and aims to provide a packaging machine and a packaging method that can reliably and effectively remove air from packaging materials or packaging bags, enabling tight packaging. [Means for solving the problem]

[0007] The present invention relates to a packaging machine comprising: a bag-making means for forming a tubular bag from a continuously supplied strip-shaped packaging material while enclosing a conveyed article; and a lateral sealing means for laterally sealing and cutting the packaging material in the width direction on the upstream and downstream sides of the article, wherein a deaeration means for removing air from the upstream side of the article contained within the packaging material is provided downstream of the lateral sealing means in the conveying direction of the article.

[0008] Furthermore, the present invention relates to a packaging method in which a strip-shaped packaging material is continuously supplied in the direction of transport of the article, the article is supplied inside while forming a tubular bag, and the packaging material containing the article is sealed laterally in the width direction and cut, the method comprising a step of removing the air on the upstream side of the article contained in the packaging material using a degassing means before completing the lateral sealing on the upstream side of the article. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a packaging machine and a packaging method that can reliably and effectively remove air from packaging materials or packaging bags, enabling tight packaging. [Brief explanation of the drawing]

[0010] [Figure 1] This is a schematic front view showing a packaging machine according to the first embodiment of the present invention. [Figure 2] This is a side view showing a part of a packaging machine according to the first embodiment of the present invention. [Figure 3] This is a plan view showing a part of a packaging machine according to the first embodiment of the present invention. [Figure 4] This is a front view illustrating the degassing operation of a packaging machine according to the first embodiment of the present invention. [Figure 5] This is a front view illustrating the degassing operation of a packaging machine according to the first embodiment of the present invention. [Figure 6] This is a front view illustrating the degassing operation of a packaging machine according to the first embodiment of the present invention. [Figure 7] This figure shows a degassing means for a packaging machine according to a second embodiment of the present invention, and is (A) a plan view, (B) a plan view, and (C) a side view. [Figure 8] This is a front view illustrating the degassing operation of a packaging machine according to a second embodiment of the present invention. [Figure 9] This is a front view illustrating the degassing operation of a packaging machine according to a second embodiment of the present invention. [Figure 10] This is a plan view showing a modified example of a degassing means according to a second embodiment of the present invention. [Modes for carrying out the invention]

[0011] The packaging machine according to the present invention will be described in detail below with reference to the drawings.

[0012] <First Embodiment> The configuration of the packaging machine 10 according to the first embodiment of the present invention will be described using Figures 1 to 6. Figure 1 is a schematic front view of the packaging machine 10, and is a front view mainly showing the vicinity of the lateral sealing device (also called the end lateral sealing device or top lateral sealing device), which is the main component of this embodiment. Figure 2 is a view of a part of the degassing means 100 as seen from the downstream side in the direction in which the article XA1 is conveyed. In each figure, some components are omitted as appropriate to simplify the drawings. Furthermore, in the following description, the direction in which the article XA1 moves from upstream to downstream is called the conveying direction T, the direction that intersects the conveying direction T and is the direction in which the lateral seal extends is called the conveying width direction W, and the direction that intersects both the conveying direction T and the conveying width direction W is called the conveying height direction H.

[0013] The packaging machine 10 shown in Figure 1 is a so-called horizontal pillow packaging machine. It uses packaging material YA1 such as resin film, which is continuously supplied along the conveying direction T, to horizontally seal and package articles XA1 that are supplied sequentially from the previous process, conveying them from upstream to downstream so that a gusset is formed. In Figure 1, the left side is upstream and the right side is downstream.

[0014] Article XA1 is, for example, a cube or a rectangular box that is close to a cube. The packaging machine 10 of this embodiment tightly packages article XA1. Here, tight packaging means that the packaging material YA1 is as close to or in close contact with article XA1 as possible, and the gusset or pillow packaging flaps (side sealing parts) are folded along the outer shape of article XA1, so that the outer shape and size of the package are close to the outer shape and size of article XA1.

[0015] The packaging machine 10 includes a belt conveyor 11 which is an upstream conveying means arranged on the upstream side, a belt conveyor 12 which is a downstream conveying means following the belt conveyor 11, a bag making device (not shown) which is upstream of the belt conveyor 11 and makes a bag from the packaging material YA1, a center seal device (not shown) which is arranged following the bag making device and center seals the packaging material YA1, a horizontal seal device 13 which is between the two belt conveyors 11, 12 and seals and cuts the packaging material YA1 along the conveying width direction W, a degassing means 100 which evacuates the air inside the packaging material YA1, a control unit (not shown) which comprehensively controls the operations of each part, and the like. Hereinafter, each component of the packaging machine 10 will be described.

[0016] The control unit (not shown) is composed of a CPU, a RAM, a ROM, etc., and executes various controls. The CPU is a so-called central processing unit, and various programs are executed to realize various functions. The RAM is used as the working area of the CPU. The ROM stores the basic OS and programs executed by the CPU.

[0017] The bag making device (not shown) is arranged upstream of the belt conveyor 11. This bag making device makes a bag in a tubular shape along the longitudinal direction of the strip-shaped packaging material YA1 while wrapping the article XA1 with the strip-shaped packaging material YA1 continuously supplied to the article XA1. That is, the bag making device functions as a bag making means for making a bag in a tubular shape while wrapping the continuously supplied strip-shaped packaging material YA1 around the conveyed article XA1, together with the center seal device described below.

[0018] The center seal device (not shown) is arranged following the bag making device. This center seal device seals (longitudinal seal) the both side edges of the tubularly bagged packaging material YA1 in the conveying direction T.

[0019] The belt conveyor 11 includes an annular belt 17 that functions as a conveying surface for carrying articles XA1 from upstream to downstream, one or more rollers (not shown) located on the upstream side, rollers 18, 19 located on the downstream side, rollers 20, 21 for adjusting the length of the belt, drive rollers (not shown) connected to a motor (not shown), and fixed frames and movable frames (not shown) that support each component, etc.

[0020] The belt 17 has an upstream running surface 17a that travels from upstream to downstream, and a return surface 17b that is positioned below the upstream running surface 17a and travels from downstream to upstream, connected in an endless manner. On the upstream running surface 17a, the belt 17 conveys articles XA1 that are wrapped in cylindrical packaging material YA1. The belt 17 travels by the rotation of drive rollers (not shown).

[0021] Rollers 18-20 are rotatably mounted on a movable frame (not shown) and can move back and forth in the direction of travel of the upstream running surface 17a as the movable frame reciprocates. In other words, when the movable frame moves downstream, the upstream running surface 17a is extended in the downstream direction, and at this time, the gap between roller 20 and roller 21 supported by the fixed frame is reduced, and the excess length of the belt 17 stored between them is unwound. On the other hand, when the movable frame moves upstream, the upstream running surface 17a is shortened, and the excess length of the belt 17 resulting from this is absorbed by the expansion of the gap between roller 20 and roller 21.

[0022] The belt conveyor 12 includes an annular belt 23 that functions as a conveying surface for carrying items XA1 from upstream to downstream, rollers 28-29 positioned on the upstream side, rollers 30, 31 for adjusting the length of the belt 23, a drive roller 32 connected to a motor (not shown), a roller 33 provided near the roller 32, a roller 34 positioned on the downstream side, and fixed and movable frames (not shown) that support each component, etc.

[0023] The belt 23 has a downstream running surface 23a that travels from upstream to downstream, and a return surface 23b that is positioned below the downstream running surface 23a and travels from downstream to upstream, connected in an endless loop. The item XA1, which has been taken over from the belt conveyor 11, is placed on the downstream running surface 23a of the belt 23. The belt 23 travels by the rotation of the rollers 32.

[0024] The rollers 28-30 are rotatably mounted on a movable frame (not shown) and can move back and forth in the direction of travel on the downstream travel surface 23a by the reciprocating movement of the movable frame. The rollers 28 are arranged near the lateral sealing device 13, spaced apart from each other in the direction of travel along the downstream travel surface 23a.

[0025] When the moving frame moves upstream, the downstream running surface 23a is extended upstream. At this time, the gap between the roller 30 and the roller 31 supported by the fixed frame narrows, and the excess length of the belt 23 stored in this gap is unwound. On the other hand, when the moving frame moves downstream, the downstream running surface 23a shortens, and the resulting excess length of the belt 23 is absorbed by the widening of the gap between the roller 30 and the roller 31.

[0026] Roller 32 is rotatably mounted to the fixed frame. This roller 32 rotates by receiving rotational power from a motor (not shown). Roller 33 is rotatably mounted to the fixed frame. This roller 33 is provided for the purpose of increasing the winding angle of the belt 23 around roller 32. Roller 34 is rotatably mounted to the fixed frame. This roller 34 folds the belt 23 back from the downstream running surface 23a to the return surface 23b. Each of the rollers 28-31, 33, and 34 other than roller 32 rotates along with the movement of the belt 23.

[0027] Note that the configuration of the belt conveyor 11 (each roller 18-21) and the belt conveyor 12 (each roller 28-34) is just one example, and the configuration is not limited to the above example, as long as the upstream running surface 17a of the belt conveyor 11 and the downstream running surface 23a of the belt conveyor 12 can move closer together and further apart, and when the two are close together, the item XA1 is transferred from the belt conveyor 11 to the belt conveyor 12.

[0028] The lateral sealing device 13 is located between the belt conveyors 11 and 12, downstream from the bag maker. This lateral sealing device 13 laterally seals and cuts the cylindrical packaging material YA1 in the width direction (conveying width direction W) of the running surfaces 17a and 23a.

[0029] Specifically, using a particular item XA1 as a reference, the lateral sealing device 13 seals and cuts the packaging material YA1 in the transport width direction W downstream of the reference item XA1 to form a bag. After that, the reference item XA1 is transported downstream, and the lateral sealing device 13 seals and cuts the packaging material YA1 in the transport width direction W upstream of the reference item XA1. Note that the operation of the lateral sealing device 13 to seal upstream of the reference item XA1 is, from the perspective of the subsequent (upstream) item XA1, the operation to seal downstream of that subsequent item XA1.

[0030] The horizontal sealing device 13 includes sealers 37 and 38 positioned opposite each other above and below the conveying height H of the packaging material YA1, holding parts 39 and 40 that hold the sealers 37 and 38, an upper sealer drive mechanism that supports and drives sealer 37 via holding part 39, and a lower sealer drive mechanism that supports and drives sealer 38 via holding part 40. The sealers 37 and 38 are substantially rectangular parallelepipeds and are positioned so that their longitudinal direction is aligned with the conveying width direction W. The upper sealer drive mechanism and the lower sealer drive mechanism respectively cause the sealers 37 and 38 to perform box motion using known configurations.

[0031] The upper sealer 37 extends in the conveying height direction H and is raised and lowered while maintaining a downward orientation by a slide bar (not shown) stretched between the holding parts 39 and 40. The lower sealer 38 is raised and lowered while maintaining an upward orientation by a slide bar. The lower sealer 38 lowers when the upper sealer 37 rises and rises when the upper sealer 37 lowers. When sealer 37 reaches its lowest position and sealer 38 reaches its highest position, sealer 37 and 38 sandwich the packaging material YA1 from above and below, seal it laterally, and cut it with a built-in cutter, separating it as a package ZA1 containing article XA1. In this way, sealers 37 and 38 function as sealing means that sandwich and seal the packaging material YA1 from above and below.

[0032] The degassing means 100 removes the air from the packaging material YA1 containing the article XA1 before the article XA1 contained in the tubular packaging material YA1 is separated as a package ZA1. This results in a tightly packaged package ZA1. The degassing means 100 of this embodiment includes, for example, an upstream degassing means 14 that removes air from the packaging material YA1 upstream of the article XA1, an upward degassing device 15 that removes air from the packaging material YA1 above the conveying height H of the article XA1, a lateral degassing device 80 that removes air from the packaging material YA1 on both sides in the conveying width W of the article XA1, and a downstream degassing means 75 that removes air from the packaging material YA1 downstream of the article XA1.

[0033] The upstream degassing means 14 is provided downstream of the lateral sealing device 13 in the conveying direction T and is a means for removing air from the upstream side of the article XA1 contained in the packaging material YA1. As an example, the upstream degassing means 14 is a substantially rectangular flat plate member made of metal or resin and includes an upper upstream degassing means 14A and a lower upstream degassing means 14B. In the example shown in Figure 1, the upper upstream degassing means 14A is substantially rectangular in shape and roughly equivalent to the downstream side surface 37s of the sealer 37 in the conveying direction T, and is in contact with and fixed to the said downstream side surface 37s. The lower upstream degassing means 14B is substantially rectangular in shape and roughly equivalent to the downstream side surface 38s of the sealer 38 in the conveying direction T, and is in contact with and fixed to the said downstream side surface 38s. That is, the upstream degassing means 14 moves simultaneously with the sealers 37 and 38 and along a trajectory (box motion) equivalent to that of the downstream side surfaces 37s and 38s. The degassing operation by the upstream degassing means 14 will be described later.

[0034] Referring to Figures 1 and 2, the upper degassing device 15 is located above the belt conveyor 12, further downstream of the lateral sealing device 13 (upstream degassing means 14). This upper degassing device 15 includes a pressing member (e.g., a sponge block) 52 that is positioned above the article XA1 from the outside of the packaging material YA1, while leaving a gap between it and the article XA1, a cylinder 53 that raises and lowers the pressing member 52, and a driving means (not shown) that reciprocates the cylinder 53 in the conveying direction.

[0035] As shown in Figure 2, the lateral degassing device 80 includes a pair of pressing members (e.g., sponge blocks, etc.) 81 positioned on the left and right sides of the article XA1 from the outside of the packaging material YA1 in the conveying width direction W, a pair of cylinders 82 that move these pressing members 81 forward and backward, and a driving means (not shown) that reciprocates the cylinders 82 in the conveying direction. The pressing member 52 and the pair of pressing members 81 are linked to each other, for example, at different timings.

[0036] Furthermore, a downstream degassing means 75 is positioned downstream of the upper degassing device 15. The downstream degassing means 75 is driven by its drive means 77. Details of the drive means 77 are omitted, but the downstream degassing means 75 is operated by a known configuration such as an actuator such as a servo motor or cylinder, or a link mechanism. The downstream degassing means 75 includes a support arm 75c that can rotate on the downstream running surface 23a around a pivot axis 75a extending in the transport width direction W, and a pressing member 75b, for example, made of a flat plate, provided at the tip of the support arm 75c. The pivot axis 75a is positioned at a sufficient height so as not to interfere with the article XA1, and the pressing member 75b can rotate within a range from a state where it is horizontal to the transport surface (downstream running surface 23a) (the state shown in Figure 1) to a state where it rotates approximately 90° clockwise to become vertical. The downstream degassing means 75 performs degassing in cooperation with the upstream degassing means 14 and the upper degassing device 15. Specifically, the drive means 77 rotates the support arm 75c clockwise in conjunction with the timing of the operation of the upstream degassing means 14 and the upper degassing device 15, pressing the pressing member 75b against the packaging material YA1 from the downstream side of the product article XA1, thereby sending the air inside the packaging material YA1 to the upstream side. At this time, the upstream side of the article XA1 is not yet sealed by the lateral sealing device 13, and degassing can be performed by the operation of the downstream degassing means 75. Once degassing is complete, the drive means 77 rotates the support arm 75c counterclockwise in preparation for the next degassing. If the pressing member 75b is made of a soft material such as sponge, it will not damage the product article XA1 and the packaging material YA1, but it may also be made of a hard material such as metal or resin.

[0037] Furthermore, the packaging machine 10 has a moving means 70 that moves the article XA1 inside the cylindrical packaging material YA1 located downstream of the horizontal sealing device 13 upstream in the conveying direction T together with the cylindrical packaging material YA1. Here, the moving means 70 may also serve as a degassing means to remove air from around the article XA1 contained within the packaging material YA1. In this embodiment, as an example, the moving means 70 also serves as a downstream degassing means 75. That is, the downstream degassing means 75 rotates the support arm 75c clockwise and presses the pressing member 75b against the packaging material YA1 from the downstream side of the article XA1 to remove air from inside the packaging material YA1, thereby moving (pushing back) the article XA1 together with the packaging material YA1 to the upstream side in the conveying direction T.

[0038] Furthermore, in conjunction with the degassing operation by the downstream degassing means 75 and the operation of moving the article XA1 upstream (pushing back operation), the sealers 37 and 38 approach and perform a lateral seal. In other words, on the upstream side of the article XA1 that the downstream degassing means 75 is pushing back, the upper upstream degassing means 14A and the lower upstream degassing means 14B move from above and below in the transport direction H and come into close proximity. The downstream degassing means 75 (moving means 70) pushes the article XA1 upstream until the upstream side of the article XA1 comes into contact with and is pressed against the upper upstream degassing means 14A and the lower upstream degassing means 14B via the packaging material YA1.

[0039] Furthermore, the upper degassing device 15 and the lateral degassing device 80 operate at a predetermined timing when the downstream degassing means 75 degassses the inside of the packaging material YA1, so that the pressing member 52 and the pair of pressing members 81 are simultaneously in close proximity to the article XA1, degassing the top and both sides of the article XA1 inside the packaging material YA1, and limiting the range of movement of the packaging material YA1 to prevent it from expanding unnecessarily. In other words, the pressing member 52 and the pair of pressing members 81 also function as restricting means that limit the range of movement of the packaging material YA1 and restrict the expansion of the packaging material YA1.

[0040] The interlocking mechanism 16 links the expansion and contraction of the upstream running surface 17a and the expansion and contraction of the downstream running surface 23a to the up and down movement of the sealers 37 and 38. It also links the up and down movement of the sealers 37 and 38 (upstream degassing means 14) to the rotation of the downstream degassing means 75, and to the state in which the pressing member 52 and the pair of pressing members 81 move closer to and further away from the article XA1. The interlocking mechanism 16 is composed of one or more combinations of, for example, a cam mechanism with a cam and a cam follower, a guide roller mechanism with a linear guide and a cam follower, a link mechanism, a servo mechanism, etc.

[0041] Referring also to Figure 3, the packaging machine 10 further includes gusset claws 90. The gusset claws 90 are, for example, rod-shaped members that extend in the conveying width direction W in a horizontal plane above the conveying surface (upstream running surface 17a, downstream running surface 23a) in the conveying height direction H, and are configured to move back and forth toward the center from both outer sides in the conveying width direction W of the packaging material YA1 by a gusset forming device (not shown). The gusset claws 90 include a pair of upstream gusset claws 90A provided on the upstream side in the conveying direction T of the lateral sealing device 13 and facing each other in the conveying width direction W, and a pair of downstream gusset claws 90B provided on the downstream side in the conveying direction T of the lateral sealing device 13 and facing each other in the conveying width direction W. The upstream gusset claw 90A and the downstream gusset claw 90B are fixed to, for example, a common support part 90C, and the gusset forming device is capable of simultaneously moving the upstream gusset claw 90A and the downstream gusset claw 90B forward and backward in the transport width direction W.

[0042] The upstream gusset claw 90A forms the downstream gusset GAd of the article XA1 immediately upstream of the lateral sealing device 13 (hereinafter referred to as upstream article XA1_1), and the downstream gusset claw 90B forms the upstream gusset GAu of the article XA1 immediately downstream of the lateral sealing device 13 (hereinafter referred to as downstream article XA1_2).

[0043] More specifically, when the upstream article XA1_1 is transported to the downstream end of the belt conveyor 11 and the upstream side of the lateral sealing device 13, the gusset forming device moves (advances) a pair of upstream gusset claws 90A, which extend in the transport width direction W, from the outside to the inside in the transport width direction W, folding both sides of the downstream packaging material YA1 of the upstream article XA1_1 inward. This forms the downstream gusset GAd of the upstream article XA1_1. At the same time, the pair of downstream gusset claws 90B are moved from the outside to the inside in the transport width direction W, folding both sides of the upstream packaging material YA1 of the downstream article XA1_2 inward. This forms the upstream gusset GAu of the downstream article XA1_2. After the gusset claws 90 have formed the gussets, the gusset forming device moves (retracts) the pair of upstream gusset claws 90A and the pair of downstream gusset claws 90B outward in the transport width direction W.

[0044] The gusset forming device performs the gusset formation operation in conjunction with the lateral sealing device 13. For example, as soon as the pair of sealers 37 and 38 of the lateral sealing device 13 come into contact with the upper and lower surfaces of the planned lateral sealing position of the packaging material YA1, the gusset forming device moves a pair of upstream gusset claws 90A and a pair of downstream gusset claws 90B inward in the conveying width direction W, bringing them into contact with both sides of the packaging material YA1. As the pair of sealers 37 and 38 of the lateral sealing device 13 approach from above and below and sandwich the packaging material YA1 from above and below, the gusset forming device further moves the pair of upstream gusset claws 90A and a pair of downstream gusset claws 90B inward in the conveying width direction W, forming gussets on both sides of the packaging material YA1. The gusset forming device heats and pressurizes the packaging material YA1 held between the pair of sealers 37 and 38 of the lateral sealing device 13 to seal and cut the packaging material YA1. As the device moves apart (retracts) in the vertical direction, it moves the pair of upstream gusset claws 90A and the pair of downstream gusset claws 90B outward in the transport width direction W, separating them from both sides of the packaging material YA1. The downstream packaging material YA1 cut by the lateral sealing device 13 becomes a package ZA1 containing the downstream article XA1_2.

[0045] In this embodiment, before one package ZA1 is separated from the packaging material YA1, the air inside the packaging material YA1 is removed by the degassing means 100, resulting in a tightly packaged package ZA1.

[0046] In the tight packaging of this embodiment, as already described, the upstream degassing means 14 removes air from the upstream side of article XA1 (downstream article XA1_2 located downstream of the lateral sealing device 13) enclosed in the packaging material YA1. As an example, the upstream degassing means 14 is fixed so as to be in contact with the respective downstream sides 37s and 38s of the sealers 37 and 38. Originally, the downstream article XA1_2, located downstream of the lateral sealing device 13, is located downstream of the sealers 37 and 38, separated from them when the sealers 37 and 38 are used for sealing. Therefore, in this embodiment, when the upstream degassing means 14 removes air from the upstream side of the downstream article XA1_2, the moving means 70 moves the downstream article XA1_2 upstream, pressing the upstream side of the downstream article XA1_2 against the upstream degassing means 14 via the packaging material YA1. This makes it possible to sufficiently degas the upstream side of the downstream article XA1_2, where degassing was previously insufficient.

[0047] As already mentioned, for example, the downstream degassing means 75 also serves as a moving means 70 that moves the article XA1 to the upstream side in the transport direction T when degassing the air inside the packaging material YA1 by pressing the pressing member 75b against the packaging material YA1 from the downstream side of the article XA1. However, the moving means 70 may be a separate means (mechanism) from the downstream degassing means 75, and may perform a push-back operation of the article XA1 in synchronization with the degassing operation by the downstream degassing means 75.

[0048] Furthermore, referring to Figure 3, the packaging machine 10 has a movement restricting means 91 that restricts the movement of an article (upstream article XA1_1) located immediately upstream of the lateral sealing device 13 during lateral sealing. The movement restricting means 91, like the gusset claw 90, is, for example, a rod-shaped member that extends in the transport width direction W in a horizontal plane above the transport surface (upstream travel surface 17a, downstream travel surface 23a) in the transport height direction H, and is configured to move back and forth toward the center from both outer sides in the transport width direction W of the packaging material YA1 by a driving means (not shown). The movement restricting means 91 may be a single rod-shaped member extending from one side (one side of the upstream article XA1_1) toward the other side in the transport width direction W, or it may be a pair (2) of rod-shaped members extending toward the center from both sides (both sides of the upstream article XA1_1) in the transport width direction W.

[0049] When the lateral sealing device 13 seals, tension is applied to the packaging material YA1, and there is a risk that the upstream article XA1_1 may move upstream due to being pushed by the packaging material YA1. In this embodiment, in order to achieve tight packaging, the article immediately downstream of the lateral sealing device 13 (downstream article XA1_2) is positioned appropriately, and degassing is performed while moving it upstream (pushing it back). The movement restricting means 91 restricts the upstream article XA1_1 from moving upstream and maintains it in an appropriate position, so that even if the upstream article XA1_1 moves after lateral sealing and becomes the downstream article XA1_2, it can maintain an appropriate position, enabling reliable degassing and tight packaging with a good appearance.

[0050] Furthermore, the degassing means 100 (each degassing device 14, 15, 75, 80) can also be described as an expansion restricting means (device) that limits the range of movement of the packaging material YA1 when removing air from the packaging material YA1, thereby regulating the amount of expansion of the packaging material YA1.

[0051] The following describes an example of the tight packaging operation in the packaging machine 10. Figures 4 to 6 are front views corresponding to Figure 1 and are schematic diagrams showing the tight packaging operation in chronological order.

[0052] Figure 4(A) shows the timing when the lateral sealing device 13 is separating the sealers 37 and 38 (for example, when sealer 37 is in the uppermost position and sealer 38 is in the lowermost position). At this timing, the lateral degassing device 80 extends a pair of pressing members 81 from the outside of the packaging material YA1 to the left and right sides of the downstream article XA1_2, pressing them against the left and right sides of the downstream article XA1_2 via the packaging material YA1 to degas. At this timing, the pressing member 52 of the upper degassing device 15 and the downstream degassing means 75 are in the initial position (standby position) shown in Figure 4(A).

[0053] Figure 4(B) shows the timing when the drive means 77 (see Figure 1) starts rotating the downstream degassing means 75 toward the downstream article XA1_2 after the lateral degassing device 80 has started degassing. The rotation of the downstream degassing means 75 causes it to come into contact with the downstream seal portion SEd of the downstream article XA1_2. As soon as the downstream degassing means 75 starts rotating (or almost simultaneously, or shortly thereafter), the upper degassing device 15 starts lowering the pressing member 52. The lateral sealing device 13 also starts moving so that the sealers 37 and 38 are in close proximity to each other.

[0054] As shown in Figure 5(A), when the downstream degassing means 75 rotates further, the downstream seal portion SEd folds down. The driving means 77 also moves the downstream degassing means 75 upstream while rotating it. That is, the driving means 77 moves the pivot shaft 75a horizontally upstream in the conveying direction T.

[0055] Furthermore, the upper degassing device 15 lowers the pressing member 52 further, bringing it into contact with the upper part of the downstream article XA1_2 via the packaging material YA1. This degasses the upper part of article XA1_2. The lateral sealing device 13 continues to move the sealers 37 and 38. As a result, sealer 37 comes into contact with the upper surface of the packaging material YA1 (planned lateral sealing position) between the upstream article XA1_1 and the downstream article XA1_2, and sealer 38 comes into contact with the lower surface of the packaging material YA1 (planned lateral sealing position) between the upstream article XA1_1 and the downstream article XA1_2.

[0056] Furthermore, the gusset forming device moves a pair of upstream gusset claws 90A and a pair of downstream gusset claws 90B inward in the conveying width direction W, approximately simultaneously with the pair of sealers 37 and 38 of the lateral sealing device 13 contacting the upper and lower surfaces of the planned lateral sealing position of the packaging material YA1, so as to contact both sides of the packaging material YA1.

[0057] Furthermore, the drive means (not shown) of the movement restricting means 91 moves inward from the outside in the transport width direction W at the timing when the pair of sealers 37, 38 come into contact with the upper and lower surfaces of the planned lateral sealing position of the packaging material YA1 (either simultaneously with or before / after contact), thereby supporting the upstream end of the upstream article XA1_1 via the packaging material YA1. When the lateral sealing device 13 seals, tension is applied to the packaging material YA1, but the movement restricting means 91 restricts the upstream article XA1_1 from moving upstream due to being pushed by the packaging material YA1.

[0058] Figure 5(B) shows the downstream degassing means 75 rotating and moving further upstream in the conveying direction T. As a result, the downstream seal portion SEd of the downstream article XA1_2 is further folded, and the downstream gusset GAd is also folded. In this example, both the pressing member 52 of the upper degassing device 15 and the pair of pressing members 81 of the lateral degassing device 80 continue to degas (restrict the expansion of the packaging material YA1) and move upstream in the conveying direction T in accordance with the movement of the downstream degassing means 75. The pair of sealers 37 and 38 move even closer together. The gusset forming device moves the pair of upstream gusset claws 90A and the pair of downstream gusset claws 90B further inward in the conveying width direction W while the sealers 37 and 38 approach from above and below and sandwich the packaging material YA1 from above and below, thereby forming gussets GA on both sides of the packaging material YA1.

[0059] Figure 5(C) shows the timing when the rotation of the downstream degassing means 75 and its movement upstream in the conveying direction T are completed. Once the rotation of the downstream degassing means 75 is complete, it becomes perpendicular (vertical) to the conveying surface, and the upstream side of the downstream article XA1_2 is sufficiently pressed against the upstream degassing means 14 via the packaging material YA1, and degassing is performed on the upstream side of the downstream article XA1_2. The gusset GAu on the upstream side of the downstream article XA1_2 is formed in a roughly triangular prism shape (with the outer surface Gs being an inclined surface) and has a three-dimensional shape with its vertex protruding in the conveying direction T (see Figure 5(B)), but when pressed against the upstream degassing means 14, the gusset GAu is folded planarly (so that the protrusion in the conveying direction T is minimized). The outer surface Gs is also roughly perpendicular to the upper and lower surfaces of the seal part SE and the upper and lower surfaces of the packaging material YA1.

[0060] At this point, when the rotation of the downstream degassing means 75 and its movement upstream in the transport direction T are completed, the sealers 37 and 38 are not in contact with the packaging material YA1 and are in an unsealed state. In other words, before the sealing of the packaging material YA1 (sealing position) by the sealers 37 and 38 is completed, the rotation of the downstream degassing means 75 and its movement upstream in the transport direction T are completed, and degassing from the downstream, upward, lateral, and upstream sides of the packaging material YA1 containing the downstream article XA1_2 is completed.

[0061] Figure 6(A) shows the timing of the lateral sealing. At this timing, the downstream degassing means 75 is stopped in the rotating position. The lateral sealing device 13 heats and pressurizes the packaging material YA1, which is sandwiched between the pair of sealers 37 and 38, to seal the packaging material YA1, and then cuts it.

[0062] The movement restricting means 91 restricts the movement of the upstream article XA1_1 until the lateral sealing is complete, and after the lateral sealing is complete, it moves (retracts) to the initial position (both outer sides of the packaging material YA1 in the transport width direction W).

[0063] Figure 6(B) shows the timing after the lateral sealing is completed by the sealers 37 and 38. The lateral seal is cut by the sealers 37 and 38, forming the downstream seal portion SEd of the upstream item XA1_1 and the upstream seal portion SEu of the downstream item XA1_2, and the downstream item XA1_2 is separated as the package ZA1. The package ZA1 is transported downstream by the belt conveyor 12.

[0064] The lateral sealing device 13 moves the sealers 37 and 38 apart (retracts) in the vertical direction, and the sealers 37 and 38 move to their initial positions. At the same time, a pair of upstream gusset claws 90A and a pair of downstream gusset claws 90B are moved outward in the conveying width direction W, and separated from both sides of the packaging material YA1. Furthermore, the drive means of the movement restricting means 91 moves the movement restricting means 91 outward in the conveying width direction W, and separates it from both sides of the packaging material YA1 (see Figure 3). The upper degassing device 15 moves the pressing member 52, and the lateral degassing device 80 moves the pressing member 82, respectively, to their initial positions. The drive means 77 of the downstream degassing means 75 moves the downstream degassing means 75, respectively, to their initial positions. That is, the pressing member 75b is rotated 90° counterclockwise to a horizontal position with respect to the conveying surface (downstream running surface 23a), and the pivot axis 75a is moved horizontally to the initial downstream position.

[0065] Here, the upstream degassing means 14 may be made of a material with high thermal conductivity. As a result, as shown in Figures 5(C) and 6(A), when the downstream article XA1_2 is pressed against the upstream degassing means 14, the heat from the sealers 37 and 38 can be transferred to the packaging material YA1 via the upstream degassing means 14. In other words, the packaging material YA1 of the downstream article XA1_2 is reshaped by heating with the upstream gusset GAu folded to the minimum extent, and a crease can be made in the minimum folded state (a state in which the gusset GAu is not spread out in a triangular shape when viewed from the front).

[0066] Thus, in this embodiment, the manufacturing method removes the air from the upstream side of the downstream article XA1_2 contained in the packaging material YA1 by the upstream degassing means 14 before completing the lateral sealing of the downstream article XA1_2 on the upstream side. Specifically, after the downstream article XA1_2 has passed through the lateral sealing device 13, the moving means 70 moves the downstream article XA1_2 upstream in the transport direction T, and presses the downstream article XA1_2 against the upstream degassing means 14 via the packaging material YA1 to degas it.

[0067] Then, after the upstream degassing means 14 removes the air from the upstream side of the downstream article XA1_2, the lateral sealing device 13 performs lateral sealing and cutting.

[0068] In this embodiment, the degassing means 100 (upstream degassing means 14, upper degassing device 15, lateral degassing device 80, and downstream degassing means 75) expel the air around the downstream article XA1_2 contained in the packaging material YA1 and perform a lateral seal. At this time, each degassing means 100 performs degassing at a timing that does not affect the operation of the lateral seal by the lateral sealing device 13. For example, at least one of these degassing means performs degassing at a different timing than the other degassing means. This ensures that the air around the downstream article XA1_2 is reliably expelled while maintaining an air passage for degassing.

[0069] Specifically, the lateral degassing device 80 degasssed the side of the downstream article XA1_2 through the packaging material YA1 before the pair of sealers 37, 38 contacted the upper and lower surfaces of the planned lateral sealing position on the packaging material YA1. The downstream degassing means 75 started degassing by pushing the downstream side of the downstream article XA1_2 through the packaging material YA1 after the lateral degassing device 80 had started degassing. The upper degassing device 15 also degassed the upper part of the downstream article XA1_2 through the packaging material YA1 after the downstream degassing means 75 had started degassing, for example, at the same time as or around the time when the pair of sealers 37, 38 contacted the upper and lower surfaces of the planned lateral sealing position on the packaging material YA1.

[0070] The downstream degassing means 75 rotates the pressing member 75b to push the downstream side of the downstream article XA1_2, but at the same time, it may also push the downstream article XA1_2 upstream in the transport direction T. It also serves as a moving means 70 for moving the downstream article XA1_2 upstream, and it can be said that the moving means 70 degasses the upstream side of the downstream article XA1_2. The downstream degassing means 75 continues to press the pressing member 75b and move it upstream even after the upper degassing device 15 has pressed the pressing member 52 against the upper part of the downstream article XA1_2 to degas it. In other words, degassing of both the downstream and upstream sides of the downstream article XA1_2 continues during this period.

[0071] The downstream degassing means 75 (moving means 70) pushes the downstream article XA1_2 upstream in the transport direction T, pressing its upstream side against the upstream degassing means 14 via the packaging material YA1. The downstream degassing means 75 (moving means 70) completes the upstream movement of the downstream article XA1_2 and its pressing against the upstream degassing means 14 between the time the pair of sealers 37, 38 contact the upper and lower surfaces of the planned lateral sealing position of the packaging material YA1 and the completion of the lateral sealing. This ensures reliable degassing and allows for the production of a package ZA1 with a good appearance. For example, if the timing of pressing against the upstream degassing means 14 is too early, wrinkles are likely to form during lateral sealing, resulting in a poor appearance. On the other hand, if pressing against the upstream degassing means 14 is not completed before lateral sealing, degassing on the upstream side of the downstream article XA1_2 will be insufficient.

[0072] Thus, when the downstream degassing means 75 also serves as the moving means 70, the process includes: removing air from around (downstream of) the downstream article XA1_2 contained within the packaging material YA1 using the moving means 70 (downstream degassing means 75); and moving the downstream article XA1_2 upstream in the transport direction T.

[0073] As an example, after removing air from above and to the sides of the downstream article XA1_2 using other degassing means (upper degassing device 15 and lateral degassing device 80), the degassing of the upstream side of the downstream article XA1_2 is completed. Specifically, the moving means 70 starts moving the downstream article XA1_2 at the timing when the lateral sealing device 13 comes into contact with the packaging material YA1, and presses the downstream article XA1_2 against the upstream degassing means 14 while the lateral sealing by the lateral sealing device 13 is completed, thereby completing the degassing of the upstream side.

[0074] The timing of the start of degassing by the upper degassing device 15, the lateral degassing device 80, and the downstream degassing means 75 may be started in any order, provided that the timing is before the pair of sealers 37 and 38 come into contact with the upper and lower surfaces of the planned lateral sealing position of the packaging material YA1.

[0075] In this example, the lateral degassing device 80 and the upward degassing device 15 move upstream in conjunction with the upstream movement of the downstream article XA1_2 by the downstream degassing means 75. The belt conveyor 12 is linked to the operation of the sealers 37 and 38 of the lateral sealing device 13, and the downstream article XA1_2 slides along the belt conveyor 12 and moves upstream.

[0076] However, this is not limited to this, and at least one or both of the lateral degassing device 80 and the upward degassing device 15 do not need to move upstream in conjunction with the upstream movement of the downstream article XA1_2.

[0077] Alternatively, either the lateral degassing device 80 or the upward degassing device 15 may also serve as a moving means 70 for moving the downstream article XA1_2 to the upstream side in the transport direction T.

[0078] When the lateral degassing device 80 also serves as a moving device 70, the process includes: removing air from the periphery (sideways) of the downstream article XA1_2 contained within the packaging material YA1 using the moving device 70 (lateral degassing device 80); and moving the downstream article XA1_2 upstream in the transport direction T.

[0079] When the upper degassing device 15 also serves as a moving device 70, the process includes: removing air from around (above) the downstream article XA1_2 contained within the packaging material YA1 using the moving device 70 (upper degassing device 15); and moving the downstream article XA1_2 upstream in the transport direction T.

[0080] The control unit comprehensively controls the degassing means 100. Specifically, the control unit operates the upstream degassing means 14, the upper degassing device 15, and the downstream degassing means 75 (and its driving means 77) in relation to the timing of the lateral sealing. For example, as shown in Figure 4(A), the control unit first presses the pressing member 81 against the side of the packaging material YA1 with the lateral degassing device 80, before the sealers 37 and 38 of the lateral sealing device 13 come into contact with the upper and lower surfaces of the packaging material YA1, thereby performing lateral degassing and limiting the range of movement of the packaging material YA1 to prevent it from expanding unnecessarily.

[0081] Subsequently, as shown in Figure 4(B), the downstream degassing means 75 is operated to bring the pushing member 75b into contact with the downstream side of the downstream article XA1_2 from the outside of the packaging material YA1, thereby initiating degassing on the downstream side and simultaneously initiating the pushing of the downstream article XA1_2 back to the upstream side.

[0082] Furthermore, at the moment when the sealers 37 and 38 of the horizontal sealing device 13 come into contact with the upper and lower surfaces of the packaging material YA1 (Figure 5(A)), the upper degassing device 15 presses the pressing member 52 against the upper part of the packaging material YA1 to degas it from above and restrict the range of movement of the packaging material YA1, thereby preventing it from expanding unnecessarily.

[0083] Furthermore, as shown in Figure 5, the control unit degasssing the downstream article XA1_2 from above and to the side using the upper degassing device 15 and the lateral degassing device 80, while further rotating and moving the downstream degassing means 75 upstream to degass the downstream side of the downstream article XA1_2, and pressing the upstream side of the downstream article XA1_2 against the upstream degassing means 14 to degass the upstream side. The pressing of the downstream article XA1_2 against the upstream degassing means 14 is performed until the lateral sealing by the lateral sealing device 13 is completed. This is the same even if the moving means 70 is the lateral degassing device 80 or the upper degassing device 15. In other words, the lateral sealing device 13 performs the lateral sealing when the pressing of the downstream article XA1_2 against the upstream degassing means 14 is complete and the air around the downstream article XA1_2, including the upstream side, has been completely removed.

[0084] <Second Embodiment> A second embodiment of the present invention will be described with reference to Figures 7 to 10. The second embodiment differs in the configuration of the downstream degassing means. The downstream degassing means is not limited to a configuration that rotates the pressing member 75b. Figure 7 shows a downstream degassing means 76 of an example of the second embodiment, where Figure 7(A) is a plan view showing the downstream degassing means 76 in its initial position, and Figure 7(B) is a plan view showing the downstream degassing means 76 in the degassing position. Figure 7(C) is a side view of Figure 7(B) viewed from the downstream side in the conveying direction T. Figures 8 and 9 show the degassing operation in the second embodiment in chronological order. Figure 10 shows a modified example.

[0085] As shown in Figures 7(A) and 7(C), the downstream deaeration means 76 includes, for example, a lateral deaeration member 76a that can contact the side of the packaging material YA1 containing the downstream article XA1_2, and a downstream deaeration member 76b that can contact the downstream gusset GAd. In other words, the downstream deaeration means 76 also serves as the lateral deaeration device 80 of the first embodiment. In this example, the lateral deaeration member 76a has the same shape as the pressing member 81 of the lateral deaeration device 80. The other components (upstream deaeration means 14, upper deaeration device 15, etc.) are the same as in the first embodiment, so their description is omitted.

[0086] As shown in Figure 7(C), the downstream degassing member 76b consists of, for example, four plate pieces 761 to 764 in a side view. Plate pieces 761 and 762, positioned above the conveying height H, face each other in the conveying width W, and their outer edges in the conveying width W are connected (fixed) to the downstream side of the lateral degassing member 76a in the conveying direction T. Plate pieces 763 and 764, positioned below the conveying height H, face each other in the conveying width W, and their outer edges in the conveying width W are connected (fixed) to the downstream side of the lateral degassing member 76a in the conveying direction T.

[0087] Plate pieces 761 and 763, positioned on one side of the transport width direction W (left side in Figure 7(C)), face each other in the transport height direction T, and are spaced apart so that the downstream seal portion SEd of the downstream item XA1_2 can be exposed. Plate pieces 762 and 764, positioned on the other side of the transport width direction W (right side in Figure 7(C)), face each other in the transport height direction T, and are spaced apart so that the downstream seal portion SEd of the downstream item XA1_2 can be exposed. This gap in which the seal portion SEd can be exposed is called the seal portion retraction space 76c.

[0088] In this example, the lateral degassing member 76a and the downstream degassing member 76b are shown to be integrated in a substantially L-shape in a plan view, but the lateral degassing member 76a and the downstream degassing member 76b may be constructed as separate parts.

[0089] The downstream degassing means 76 in this example also removes air from around the downstream article XA1_2 contained within the packaging material YA1 (downstream and to the side), and can also move the downstream article XA1_2 upstream in the transport direction (i.e., it also serves as the moving means 70). Furthermore, the downstream degassing means 76 also incorporates the functions of the lateral degassing device 80 described above. The rest of the configuration is the same as in the first embodiment.

[0090] The operation of the tight packaging of the second embodiment will be described with reference to Figures 7 to 9. At the timing shown in Figure 8(A), the lateral sealing device 13 separates the sealers 37 and 38 (for example, sealer 37 is in the uppermost position and sealer 38 is in the lowermost position). The downstream degassing means 76 is in its initial position. As shown in Figure 7(A), the downstream degassing means 76 in its initial position is located on both outer sides of the packaging material YA1 in the conveying width direction W. In the conveying direction T, it is positioned such that the downstream sealing portion SEd of the downstream item XA1_2 and the downstream degassing member 76b are aligned.

[0091] Then, at the timing of degassing the downstream side of the downstream article XA1_2, the driving means (not shown) of the downstream degassing means 76 moves (advances) the downstream degassing means 76 from the outside to the inside in the transport width direction W, as shown in Figure 7(B), and presses the lateral degassing member 76a against the left and right sides of the downstream article XA1_2 via the packaging material YA1 to degas it.

[0092] At this time, the downstream degassing member 76b also extends into the downstream seal portion SEd of the downstream item XA1_2, but the seal portion SE enters the seal portion retraction space 76c. In other words, the downstream degassing member 76b covers the downstream gusset GAd without interfering with the seal portion SE (Figure 7(B), Figure 8(A)). At this timing, the downstream gusset GAd of the downstream item XA1_2 remains in a roughly triangular prism shape, and in the transport direction T, the downstream degassing member 76b is at the position of the downstream seal portion SEd, so the three-dimensional shape of the downstream gusset GAd is maintained.

[0093] Figure 8(B) shows the timing when the downstream degassing means 76 begins to move upstream. The lateral degassing member 76a continues to degas the left and right sides of the downstream article XA1_2, and as the downstream degassing member 76b moves upstream in the transport direction T, the downstream article XA1_2 is pushed back upstream, and the downstream gusset GAd is pushed in the folding direction. This also starts degassing the downstream side of the downstream article XA1_2.

[0094] When the downstream degassing means 76 begins degassing downstream of the downstream article XA1_2 (almost simultaneously or immediately thereafter), the upward degassing device 15 begins to lower the pressing member 52. The lateral sealing device 13 also begins to move so that the sealers 37 and 38 are in close proximity to each other.

[0095] Figure 8(C) shows the timing when the upper degassing device 15 lowers the pressing member 52 and contacts the upper part of the downstream article XA1_2 via the packaging material YA1, thereby performing degassing.

[0096] Furthermore, the lateral sealing device 13 continues to move the sealers 37 and 38, so that sealer 37 contacts the upper surface of the packaging material YA1 (planned lateral sealing position) between the upstream article XA1_1 and the downstream article XA1_2, and sealer 38 contacts the lower surface of the packaging material YA1 (planned lateral sealing position) between the upstream article XA1_1 and the downstream article XA1_2, pushing the upper and lower surfaces of the packaging material YA1 at the planned lateral sealing position inward.

[0097] The downstream degassing means 76 moves further upstream in the conveying direction T. As a result, the downstream gusset GAd of the downstream article XA1_2 is also folded further. In this example, the pressing member 52 of the upper degassing device 15 also moves upstream in the conveying direction T in accordance with the movement of the downstream degassing means 75.

[0098] Furthermore, the gusset forming device moves a pair of upstream gusset claws 90A and a pair of downstream gusset claws 90B inward in the conveying width direction W approximately at the same time that the pair of sealers 37 and 38 of the lateral sealing device 13 contact the upper and lower surfaces of the planned lateral sealing position of the packaging material YA1, thereby pressing in both sides of the packaging material YA1.

[0099] Furthermore, the drive means (not shown) of the movement restricting means 91 moves the pair of sealers 37, 38 inward from the outside in the transport width direction W at the timing when they come into contact with the upper and lower surfaces of the planned lateral sealing position of the packaging material YA1 (either simultaneously with or before / after contact), thereby supporting the upstream end of the upstream article XA1_1 via the packaging material YA1.

[0100] As the sealers 37 and 38 approach from above and below respectively and clamp the packaging material YA1 from above and below, a pair of upstream gusset claws 90A and a pair of downstream gusset claws 90B are further moved inward in the transport width direction W, so that downstream gussets GAd are formed on both sides of the packaging material YA1 that contains the upstream article XA1_1, and upstream gussets GAu are formed on both sides of the packaging material YA1 that contains the downstream article XA1_2.

[0101] Figure 9(A) shows the timing when the downstream degassing means 76 has completed its upstream movement in the transport direction T. When the downstream degassing means 75 completes its upstream movement, the upstream side of the downstream article XA1_2 is sufficiently pressed against the upstream degassing means 14 (14a, 14b) via the packaging material YA1, and degassing is performed on the upstream side of the downstream article XA1_2. The upstream gusset GAu of the downstream article XA1_2 is roughly triangular prism-shaped when formed, with its vertex protruding in the transport direction T. However, by pressing it against the upstream degassing means 14, the upstream gusset GAu of the downstream article XA1_2 is folded planarly (to minimize the protrusion in the transport direction T), and the inclined outer surface Gs (see Figure 8(C)) when formed becomes roughly perpendicular to the upper and lower surfaces of the seal part SE and the upper and lower surfaces of the packaging material YA1.

[0102] On the downstream side of the downstream item XA1_2, the gusset GAd is also folded, and the inclined outer surface Gs (see Figure 8(C)) that was formed becomes approximately perpendicular to the upper and lower surfaces of the seal portion SE and the upper and lower surfaces of the packaging material YA1. Degassing on the downstream side is also completed.

[0103] At this point, when the downstream degassing means 76 has completed its upstream movement in the transport direction T, the sealers 37 and 38 are not in contact with the packaging material YA1 and are in an unsealed state. In other words, before the sealing of the packaging material YA1 (sealing location) by the sealers 37 and 38 is completed, the downstream degassing means 76 has completed its upstream movement in the transport direction T, and the degassing of the downstream, upward, lateral, and upstream areas within the packaging material YA1 containing the downstream article XA1_2 is completed.

[0104] Figure 9(B) shows the timing of the lateral sealing. At this timing, the downstream degassing means 76 is stopped at the upstream position in the conveying direction T. The lateral sealing device 13 heats and pressurizes the packaging material YA1, which is sandwiched between a pair of sealers 37 and 38, to seal the packaging material YA1, and then cuts it.

[0105] The movement restricting means 91 restricts the movement of the upstream article XA1_1 until the lateral sealing is complete, and after the lateral sealing is complete, it moves (retracts) to the initial position (both outer sides of the packaging material YA1 in the transport width direction W).

[0106] Subsequently, although not shown in the diagram, the lateral seal positions are cut by sealers 37 and 38, forming the downstream seal portion SEd of the upstream article XA1_1 and the upstream seal portion SEu of the downstream article XA1_2, and the downstream article XA1_2 is separated as the package ZA1. The package ZA1 is transported downstream by the belt conveyor 12.

[0107] The lateral sealing device 13 moves the sealers 37 and 38 apart (retracts) in the vertical direction, and the sealers 37 and 38 move to their initial positions. At the same time, a pair of upstream gusset claws 90A and a pair of downstream gusset claws 90B move outward in the conveying width direction W, separating them from both sides of the packaging material YA1. Furthermore, the drive means of the movement restricting means 91 moves the movement restricting means 91 outward in the conveying width direction W, separating it from both sides of the packaging material YA1. The upper degassing device 15 moves the pressing member 52, the lateral degassing device 80 moves the pressing member 82, and the drive means of the downstream degassing means 75 moves the downstream degassing means 75 to their initial positions.

[0108] In the second embodiment as well, the downstream degassing means 76 is driven by a drive means (not shown) to perform the downstream degassing operation and the operation of pushing the article XA1 back to the upstream side. The gusset claw 90 is driven by a gusset forming device to perform a gusset forming operation. The movement restricting means 91 is driven by its drive means (not shown) to perform a movement restricting operation that restricts the article XA1 from being pushed back upstream. The control unit comprehensively controls the degassing means 100.

[0109] In the second embodiment, the downstream degassing means 76 also serves as a moving means 70 for moving the downstream article XA1_2 to the upstream side. In other words, the packaging method in this case also includes the steps of the moving means 70 removing air from around the downstream article XA1_2 (downstream and lateral) which is enclosed in the packaging material YA1, and moving the downstream article XA1_2 upstream in the transport direction T. Tight packaging is achieved by removing air from the upstream side of the downstream article XA1_2 with the downstream degassing means 76 before completing the lateral seal on the upstream side of the downstream article XA1_2.

[0110] In this case as well, the upstream degassing means 14 can be made of a material with high thermal conductivity. As a result, as shown in Figure 8, when the downstream article XA1_2 is pressed against the upstream degassing means 14, the heat from the sealers 37,38 is transferred to the packaging material YA1 via the upstream degassing means 14, and the upstream gusset GAu can be folded in the smallest possible state.

[0111] The downstream degassing means 76 of the second embodiment degassed the downstream article XA1_2 contained in the packaging material YA1 simultaneously on the downstream and lateral sides, thus simplifying the configuration and control compared to the first embodiment.

[0112] Figure 10 is a plan view showing a modified example of the second embodiment. The downstream degassing means 76 may be provided with only a downstream degassing member 76b, or a lateral degassing means 77 separate from the downstream degassing means 76 may be provided. The lateral degassing means 77 is, for example, a pair of plate-like members that can contact both sides of the packaging material YA1 containing the downstream article XA1_2, and is, for example, attached to the support portion 90C of the gusset claw 90 of the gusset forming device, and moves back and forth together with the gusset claw 90. The lateral degassing means 77 may be separate from the gusset claw 90 and move back and forth laterally to the article XA1 in synchronization with the gusset claw 90.

[0113] Although not shown in the illustration, the downstream degassing member 76b may be configured to change the spacing between plate pieces 761 and 763 and between plate pieces 762 and 764 during packaging. In this case, once it comes into contact with the outer surface Gs of the cylindrical packaging material YA1, the spacing between plate pieces 761 and 763 and between plate pieces 762 and 764 is narrowed in the conveying height direction H. This allows for more thorough degassing of the downstream article XA1_2.

[0114] In the first and second embodiments described above, the upstream degassing means 14 is provided downstream of the lateral sealing device 13 in the conveying direction T, and is configured to move up and down in synchronization with at least the lifting and lowering movement of the lateral sealing device 13. That is, it is not limited to being fixed to the lateral sealing device 13, but may be provided separately from the lateral sealing device 13 and be able to move up and down by a driving means for moving the upstream degassing means 14 up and down. Furthermore, a driving means for moving the upstream degassing means 14 upstream and downstream in the conveying direction T may be provided, and instead of moving the article XA1 upstream as described above, the upstream degassing means 14 may be moved downstream to degass the upstream side of the article XA1.

[0115] Furthermore, the downstream degassing means 75 and 76 may be provided with a heating means for heating the packaging material YA1. This allows the downstream gusset GAd to be folded in the smallest possible state.

[0116] Furthermore, the article XA1 does not have to be cubic. Also, the packaging does not have to be tight packaging. Because the degassing means 100 surrounds the article XA1 and allows for lateral sealing while applying internal air pressure within the cylindrical packaging material YA1, even if the article XA1 is not cubic, for example, spherical, it can be packaged in a substantially cubic shape as the packaging ZA1.

[0117] Furthermore, the pressing member 52 of the upper degassing device 15 may be configured to move up and down independently of the upper sealer 37 by a separate drive from the sealer 37.

[0118] Furthermore, it is preferable to move the downstream article XA1_2 backward (towards the upstream side) when the upper sealer 37 is lower than the height of article XA1. Even when article XA1_2 is moved backward, the sealer 37 acts as a stopper, preventing the upstream side of article XA1 from getting caught in the lateral sealing device 13.

[0119] The present invention is not limited to the embodiments described above, and various modifications are possible without departing from its spirit and technical concept.

[0120] Alternatively, in the above embodiment, either the upper pressing member 52 or the pair of left and right side pressing members 81, or both thereof, may be fixed in an immovable manner. [Explanation of Symbols]

[0121] 10 Packaging machine 11,12 Belt conveyor 13. Lateral sealing device 14 Upstream degassing means 14A Upstream degassing means 14B Downward Upstream Degassing Means 15. Upward degassing device 16 Interlocking mechanism 17 belts 17a Upstream running surface (conveying surface) 23 belts 23a Downstream running surface (conveying surface) 37s, 38s downstream side 37,38 Sealer 39,40 Holding part 52 Pressing member 81 Pressing member 70 Means of Transportation 75 Downstream degassing means 75a Rotary shaft 75b Pressing member 75c support arm 76 Downstream degassing means 76a Lateral degassing member 76b Downstream degassing member 76c Seal area retraction space 77 Driving means 80. Lateral degassing device 90 gusset claws 90A Upstream gusset claw 90B Downstream gusset claw 90C support part 91 Movement control measures 100 Degassing method

Claims

1. A bag-making means that forms a tubular bag from a continuously supplied strip of packaging material while wrapping the conveyed articles, The package includes a transverse sealing means for transversely sealing and cutting the packaging material in the width direction on the upstream and downstream sides in the conveying direction of the article, A degassing means is provided downstream of the transverse sealing means in the conveying direction to remove air from the upstream side of the article contained in the packaging material. A packaging machine characterized by the following features.

2. The moving means has a mechanism for moving the article downstream of the lateral sealing means to an upstream position in the conveying direction. The packaging machine according to feature 1.

3. The aforementioned moving means also serves as another degassing means for removing air from around the article contained within the packaging material. The packaging machine according to feature 2.

4. The other degassing means is a downstream degassing means that removes air from the downstream side of the article. The packaging machine according to feature 3.

5. The degassing means moves in synchronization with the lateral sealing means. The packaging machine according to feature 1.

6. The aforementioned degassing means is made of a material with high thermal conductivity. The packaging machine according to feature 1.

7. A packaging method comprising continuously supplying a strip-shaped packaging material in the direction of transport of the article to form a tubular bag while supplying the article inside, and packaging the article by horizontally sealing and cutting the packaging material containing the article in the width direction, The process involves moving the article upstream in the transport direction after the article has passed through a lateral sealing means that performs lateral sealing, The process includes, before the lateral sealing of the upstream side of the article is completed, pressing the article against a degassing means through the packaging material, and using the degassing means to remove the air from the upstream side of the article contained within the packaging material. A packaging method characterized by the following features.

8. The process of removing air from around the article enclosed in the packaging material by the means of transport, The process includes moving the article upstream in the transport direction, The packaging method according to feature 7.

9. After the air is removed from the upstream side of the article by the degassing means, the lateral sealing means performs a lateral seal. The packaging method according to feature 7.

10. After degassing from above and to the sides of the article is performed by other degassing means, degassing from the upstream side of the article is completed. The packaging method according to feature 7.

11. The moving means starts moving the article at the timing when the lateral sealing means comes into contact with the packaging material, and completes pressing the article against the degassing means before the sealing by the lateral sealing means is completed. The packaging method according to feature 7.

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