Heat sealing device

Abstract

Provided is a heat sealing device that seals a film for packaging an article by heat welding, the film being arranged in a state of sandwiching the article and partially overlapping each other around the article. The heat sealing device is provided with: a sealing head that applies heat welding to a sealed part sealed in the film; a first cooling head that cools the sealed part after heat welding by the sealing head; and a second cooling head that cools at least a part of an article side region on the side closer to the article than the sealed part in the film.

Description

Technical Field

[0001] The present disclosure relates to a heat-sealing device.

Background Art

[0002] As a film for packaging an article, a heat-sealable film such as a plastic film is known, and a heat-sealing device for sealing this film by heat welding is known. The heat-sealing device seals a film that sandwiches an article and is disposed in a state where a part thereof is overlapped around the article by heat welding. The heat-sealing device includes a seal head that heat-welds a seal portion of the film.

[0003] After the film is sealed by the seal head, for example, tension is applied to transfer the packaged article. However, if the seal portion is heated when tension is applied to the film, the film may stretch. Since it takes time for the seal portion to cool naturally, in order to increase the throughput of the heat-sealing process, some heat-sealing devices are provided with a cooling head that cools the seal portion after heat welding by the seal head (see Japanese Patent Application Laid-Open No. 2009-242000 and Japanese Patent Application Laid-Open No. 2004-237675).

[0004] On the other hand, Japanese Utility Model Publication No. 58-21503 discloses a heat-sealing device for continuously packaging a plurality of articles. Specifically, the heat-sealing device described in Japanese Utility Model Publication No. 58-21503 uses a long film extending in the arrangement direction of a plurality of articles, and seals the film covering the plurality of articles in a band shape by a seal bar (corresponding to a seal head) between the articles, and cuts the center of the seal portion with a cutter after sealing.

[0005] In the heat-sealing device described in Japanese Utility Model Publication No. 58-21503, a cooling bar (corresponding to a cooling head) is provided to cool the vicinity of the seal portion sealed by a seal bar during heat welding of the film. The cooling bar described in Japanese Utility Model Publication No. 58-21503 suppresses the occurrence of pinholes in the seal portion softened by heating of the seal bar by cooling the vicinity of the seal portion.

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the heat-sealing devices disclosed in JP-A-2009-242000 and JP-A-2004-237675, although the seal portion can be cooled by a cooling head, there is a problem that it is difficult to suppress heat damage to an article caused by the heat of the seal head during heat welding of the seal portion. This becomes particularly problematic when sealing a film for packaging an article sensitive to heat, such as an article that is likely to be altered or deformed by heat.

[0007] Also in the heat-sealing device described in Japanese Utility Model Publication No. 58-21503, the cooling bar (cooling head) is for cooling the vicinity of the seal portion and does not consider heat damage to the article.

[0008] The present disclosure has been made in view of the above circumstances, and an object thereof is to provide a heat-sealing device capable of suppressing heat damage to an article packaged with a film while improving the throughput of heat sealing.

Means for Solving the Problems

[0009] The heat-sealing device of the present disclosure is a heat-sealing device for heat-sealing a film for packaging an article, the film being arranged in a state of sandwiching the article and having a part thereof overlapped around the article, a seal head for heat-sealing a seal portion to be sealed in the film, a first cooling head for cooling the seal portion after heat welding by the seal head, A heat-sealing device comprising a second cooling head that cools at least a part of an article-side region of a film that is on the article side of a seal portion.

[0010] In the heat-sealing device of the present disclosure, it is preferable to include a moving mechanism that relatively moves each of the seal head, the first cooling head, and the second cooling head with respect to the film, and a control unit that controls each part of the seal head, the first cooling head, the second cooling head, and the moving mechanism.

[0011] In the heat-sealing device of the present disclosure, after starting the cooling of the article-side region by bringing the second cooling head into contact with the article-side region by the moving mechanism, it is preferable to start the heat welding of the seal portion by bringing the seal head into contact with the seal portion by the moving mechanism.

[0012] In the heat-sealing device of the present disclosure, after heat welding by the seal head, it is preferable to retract the seal head from the seal portion by the moving mechanism and bring the first cooling head into contact with the seal portion by the moving mechanism.

[0013] In the heat-sealing device of the present disclosure, it is preferable for the control unit to continue cooling the article-side region by the second cooling head from the start of heat welding of the seal portion by the seal head until the cooling of the seal portion by the first cooling head is completed.

[0014] In the heat-sealing device of the present disclosure, it is preferable for the control unit to control the temperature of at least one of the first cooling head and the second cooling head to a preset temperature.

[0015] In the heat-sealing device of the present disclosure, the preset temperature is preferably 20°C or lower.

[0016] In the heat-sealing device of the present disclosure, it is preferable for the control unit to control the pressing pressure on the contact region when the second cooling head is brought into contact with the article-side region.

[0017] In the heat-sealing device of the present disclosure, when cooling the article-side region, it is preferable that the end position on the seal head side of the pressing surface that presses the article-side region of the film is located closer to the seal head side than the end position on the seal head side of the article.

[0018] In the heat-sealing device of the present disclosure, when cooling the article-side region, it is preferable that the pressing surface of the second cooling head that presses the article-side region of the film is disposed at a position facing at least the outer peripheral edge of the article.

[0019] In the heat-sealing device of the present disclosure, when cooling the article-side region, it is preferable that the pressing surface of the second cooling head that presses the article-side region of the film is disposed at a position facing the entire surface of the article.

[0020] In the heat-sealing device of the present disclosure, the pressing surface may protrude from the article side to the seal head side with respect to the position facing the outer peripheral edge of the article.

[0021] In the heat-sealing device of the present disclosure, when the width of the seal head is LH and the distance between the seal head and the second cooling head is D, the relationship between D and LH is LH / 1000 < D < 10LH and it is preferable that this is the case.

[0022] In the heat-sealing device of the present disclosure, when the width of the seal head is LH and the width of the first cooling head is LC, the relationship between LH and LC is LH / 2 < LC and it is preferable that this is the case.

[0023] In the heat-sealing device of the present disclosure, the seal portion is provided in a manner surrounding the entire circumference of the article, and it is preferable that the seal head also has a frame shape corresponding to the shape of the seal portion.

Advantages of the Invention

[0024] According to the heat-sealing device of the present disclosure, it is possible to improve the throughput of heat-sealing while suppressing heat damage to the articles packaged by the film.

Brief Description of the Drawings

[0025]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Embodiments for Carrying Out the Invention

[0026] Hereinafter, embodiments of the technology of the present disclosure will be described with reference to the drawings.

[0027] [Heat Sealing Device] FIG. 1 is a perspective view showing a schematic configuration of a heat sealing device 10 according to an embodiment of the present disclosure. The heat sealing device 10 is a device for heat-sealing films 2a and 2b for packaging an article 1 (see FIGS. 2 and 3), the films 2a and 2b being arranged in a state of sandwiching the article 1 and having a part thereof overlapped around the article 1. The heat sealing device 10 of the present embodiment includes a sealing head 12, a first cooling head 14, and a second cooling head 16 in a housing 11. In the present embodiment, for convenience of explanation, the horizontal plane is defined as the XY plane, the longitudinal direction of the housing 11 is the X direction, the short-side direction is the Y direction, and the direction perpendicular to the XY plane is the Z direction. That is, the Z direction is a direction along the vertical direction (up and down direction).

[0028] Further, a pallet 5 is provided on the housing 11. The article 1 is placed on the pallet 5 in a state of being sandwiched between the film 2a and the film 2b. In this example, with the film 2a spread on the pallet 5, the article 1 is placed on the film 2a, and the film 2b is overlapped from above the article 1.

[0029] Figure 2 is a plan view and a cross-sectional view showing a state in which the film 2a, the article 1, and the film 2b are overlapped. In the plan view of Figure 2, a part of the film 2b is cut out to show the film 2a. The planar sizes of the film 2a and the film 2b are larger than the planar size of the article 1. The article 1 is disposed substantially at the center of the film 2a and the film 2b, and in the peripheral portions of the film 2a and the film 2b around the article 1, the film 2a and the film 2b overlap in a state of direct contact. A part of the portion where the film 2a and the film 2b are in direct contact becomes a seal portion 6 where the film 2a and the film 2b are sealed. In this example, the seal portion 6 sealed in the film 2a and the film 2b is a belt-like region indicated by a one-dot chain line in the figure provided in a manner surrounding the entire circumference of the article 1. In this specification, the region on the article 1 side with respect to the seal portion 6 is referred to as an article side region 8. In the following, when it is necessary to distinguish between the film 2a and the film 2b, a detailed symbol of a or b is attached for distinction, and when there is no need to distinguish, it is simply referred to as the film 2 without attaching a detailed symbol.

[0030] The heat sealing device 10 further includes a moving mechanism 18 that relatively moves each of the seal head 12, the first cooling head 14, and the second cooling head 16 with respect to the film 2, and a control unit 90 that controls each part of the seal head 12, the first cooling head 14, the second cooling head 16, and the moving mechanism 18 (see Figure 4).

[0031] Figure 3 is a view showing a state in which the seal head 12, the first cooling head 14, and the second cooling head 16 are moved from the position in Figure 1 in the heat sealing device 10. Specifically, in Figure 3, the seal head 12 and the first cooling head 14 have moved in the X direction from the position in Figure 1, and the second cooling head 16 has moved upward in the Z direction from the position in Figure 1. Figure 4 shows a front schematic view of the heat sealing device 10 and a schematic view of the functional configuration of the control unit 90. Figure 5 is a side schematic view of the heat sealing device 10.

[0032] The sealing head 12 heat-seals the sealing portion 6 of the film 2. In this example, the sealing head 12 has a frame shape with a rectangular outer shape, and a sealing surface 20 that contacts the film 2 is formed on the surface facing the film 2. The sealing surface 20 has the same shape as the shape of the sealing portion 6 that surrounds the outer periphery of the article 1 and faces the sealing portion 6. Inside the sealing head 12, a heating heater (not shown) and a temperature sensor 21 (see FIG. 4) are incorporated. When the heating heater operates, the sealing surface 20 of the sealing head 12 is heated. The temperature sensor 21 detects the temperature of the sealing surface 20. The sealing head 12 is preferably made of a material with high heat conduction efficiency such as metal like stainless steel or ceramics. As shown in FIG. 2, in this example, the sealing portion 6 is provided in a manner that surrounds the entire circumference of the article 1, and the shape of the sealing head 12 is a frame shape corresponding to the shape of the sealing portion 6. In this example, since the article 1 has a rectangular shape, the sealing head 12 has a frame shape with a rectangular opening 22 corresponding to the shape of the article 1. Thereby, the sealing portion 6 that surrounds the entire circumference of the article 1 can be sealed at once. As the frame shape, in this example, it is a rectangular frame, but it may be an annular frame, a polygonal frame other than a rectangle, etc. according to the article. The sealing head 12 has the heated sealing surface 20 pressed against the sealing portion 6 by the heating heater, and heat-seals this sealing portion 6. Note that in this example, the shape of the sealing surface 20 of the sealing head 12 is a similar shape along the outer shape of the article 1, but if the shape of the sealing surface 20 is larger than the outer shape of the article 1, it does not have to be similar to the outer shape of the article 1. Also, the sealing portion 6 does not necessarily have to be the entire outer periphery, and may be a part of the outer periphery. How to set the shape of the sealing portion 6 is appropriately determined according to the design.

[0033] The first cooling head 14 cools the seal portion 6 after heat welding by the seal head 12. In this example, similar to the seal head 12, the first cooling head 14 has a rectangular frame shape in outer contour, and a pressing surface 40 that contacts the film 2 is formed on the surface facing the film 2. The pressing surface 40 has substantially the same frame shape as the seal surface 20 of the seal head 12 and faces the seal portion 6. Inside the first cooling head 14, a cooling element (not shown) and a temperature sensor 41 (see FIG. 4) are incorporated. When the cooling element operates, the pressing surface 40 is cooled. The first cooling head 14 is preferably made of a material with high heat conduction efficiency, such as a metal like aluminum. In this example, the shape of the first cooling head 14 is the same as that of the seal head 12 and is a frame shape having a rectangular opening 42. After heat welding by the seal head 12, the pressing surface 40 cooled by the cooling element is pressed against the seal portion 6, and the seal portion 6 is cooled.

[0034] Note that the shape of the pressing surface 40 of the first cooling head 14 does not necessarily have to be the same as the seal surface 20 as long as the seal portion 6 can be cooled. It is appropriately determined according to the shape of the seal portion 6 or the shape of the seal head 12, etc.

[0035] Also, when the width of the seal head 12 is LH (see FIGS. 3 and 6) and the width of the first cooling head 14 is LC (see FIG. 3), the relationship between LH and LC is preferably LH / 2 < LC. Here, LH corresponds to the width of the seal portion 6. More specifically, in this example, the seal portion 6 has a rectangular frame shape, and the width of the seal portion 6 refers to the width in the direction orthogonal to the direction in which one side of the rectangular frame extends. And in this example, corresponding to the shape of the seal portion 6, both the seal head 12 and the first cooling head 14 have a rectangular frame shape, and LH and LC also refer to the width in the direction orthogonal to the direction in which one side of the rectangular frame shape extends, as shown in FIGS. 3 and 6. If LC is larger than half of LH, it is effective for cooling because more than half of the seal portion 6 can be cooled. However, it is preferable that the entire seal portion 6 can be pressed. When the seal head 12 and the first cooling head 14 have an annular frame shape, LH and LC are the widths in the radial direction of the annulus in the annular line.

[0036] The second cooling head 16 cools at least a part of the article-side region 8 on the article 1 side of the film 2 relative to the seal portion 6. The second cooling head 16 has a pressing surface 60 having the same size and shape as the article 1 in this example. Inside the second cooling head 16, a cooling element (not shown) and a temperature sensor 61 (see FIG. 4) are incorporated. When the cooling element operates, the pressing surface 60 is cooled. In this example, the shape of the second cooling head 16 is flat, and the planar shape is rectangular. The planar size of the second cooling head 16 is smaller than the planar size of the opening 22 of the seal head 12. In this embodiment, the second cooling head 16 presses the pressing surface 60 against the article-side region 8 of the film 2b. The film 2b is in contact with the peripheral surface (the upper surface in this example) of the article 1. Therefore, by pressing the pressing surface 60 of the second cooling head 16 against the article-side region 8 of the film 2, the peripheral surface of the article 1 is pressed by the pressing surface 60 via the film 2b. Thereby, the article 1 is cooled. That is, while the first cooling head 14 has a function of cooling the seal portion 6, the second cooling head 16 has a function of cooling the article 1 via the film 2b.

[0037] The cooling elements provided in the first cooling head 14 and the second cooling head 16 are, for example, Peltier elements, but the cooling elements may be provided with other cooling mechanisms such as air cooling or water cooling.

[0038] FIG. 6 is a diagram showing the positional relationship between the seal head 12 and the second cooling head 16 in the present embodiment. The upper figure is a plan view, and the lower figure is a cross-sectional view taken along line 6B-6B. As shown in FIG. 6, the second cooling head 16 is pressed against the article 1 via the film 2b, and the seal head 12 is pressed against the seal portion 6 surrounding the article 1. An interval D is provided between the seal head 12 and the second cooling head 16 to prevent interference with each other when the seal head 12 and the second cooling head 16 move up and down. Specifically, the interval D is the distance between the inner peripheral surface of the frame-shaped seal head 12 and the outer peripheral surface of the second cooling head 16. If the interval D is several μm or more, for example, 2 μm or more, the seal head 12 and the second cooling head 16 can move up and down without interfering with each other. It is preferable that the interval D satisfies LH / 1000 < D < 10LH when the width LH of the seal head 12, which is the width of the seal portion 6, is set. Note that the width LH of the seal head 12 may be appropriately set according to the article or the like, but is, for example, 1 mm to 20 mm.

[0039] In the present embodiment, as shown in FIGS. 1, 3, and 4, the moving mechanism 18 includes a seal head Z-direction moving portion 28, a first cooling head Z-direction moving portion 48, a second cooling head Z-direction moving portion 68, and an X-direction moving portion 70 that moves the seal head 12 and the first cooling head 14 in the X direction. The seal head Z-direction moving portion 28 moves the seal head 12 in the Z direction. The first cooling head Z-direction moving portion 48 moves the first cooling head 14 in the Z direction. The seal head Z-direction moving portion 28 moves the seal head 12 in the Z direction. The second cooling head Z-direction moving portion 68 moves the second cooling head 16 in the Z direction.

[0040] In this example, the seal head Z-direction moving part 28 is composed of two cylinders 26a and 26b and two shafts 24a and 24b extending in the Z direction. A part of the upper end side of the shaft 24a is accommodated in the cylinder 26a. By changing the accommodation amount of the shaft 24a in the cylinder 26a on the upper end side, the part of the shaft 24a protruding downward from the cylinder 26a expands and contracts in the Z direction. An actuator for expanding and contracting the shaft 24a is built into the cylinder 26a. The actuator is composed of, for example, a hydraulic pump, a motor, a solenoid, and the like. In this way, a telescopic mechanism is constituted by a set of one cylinder 26a and one shaft 24a extending in the Z direction. The set of the cylinder 26b and the shaft 24b also constitutes a telescopic mechanism similar to the set of the cylinder 26a and the shaft 24a. The seal head Z-direction moving part 28 is composed of these two sets of telescopic mechanisms.

[0041] The lower ends of the shafts 24a and 24b that constitute each telescopic mechanism are respectively attached to the opposing two sides of the frame-shaped seal head 12. When each of the shafts 24a and 24b expands and contracts with respect to each of the cylinders 26a and 26b, the position of the seal head 12 in the Z direction changes. In this way, the seal head Z-direction moving part 28 raises and lowers the seal head 12 with respect to the film 2. In addition, so that the seal surface 20 does not tilt when the seal head 12 moves up and down, in the seal head Z-direction moving part 28, the two sets of telescopic mechanisms are driven synchronously so that the expansion and contraction amounts match. In FIG. 1, each of the shafts 24a and 24b is shown in a state of being extended with respect to each of the cylinders 26a and 26b and pressing the seal part 6 with the seal surface 20 of the seal head 12. Further, in FIG. 3, each of the shafts 24a and 24b is shown in a state of being contracted with respect to each of the cylinders 26a and 26b.

[0042] The Z-direction moving part 48 of the first cooling head in this example also has substantially the same configuration as the Z-direction moving part 28 of the sealing head. That is, the Z-direction moving part 48 of the first cooling head is composed of two cylinders 46a and 46b and two shafts 44a and 44b extending in the Z direction. The two cylinders 46a and 46b and the two shafts 44a and 44b extending in the Z direction constitute two sets of telescopic mechanisms. The cylinders 46a and 46 have the same actuators as the cylinders 26a and 26b. The lower ends of the respective shafts 44a and 44b constituting each telescopic mechanism have one ends of the shafts 44a and 44b attached to the respective opposing two sides of the frame-shaped first cooling head 14. When the shafts 44a and 44b expand and contract with respect to the cylinders 46a and 46b, the position of the first cooling head 14 in the Z direction changes. In this way, the Z-direction moving part 48 of the first cooling head raises and lowers the first cooling head 14 with respect to the film 2.

[0043] The Z-direction moving part 68 of the second cooling head is composed of a cylinder 66 and a shaft 64 extending in the Z direction. The cylinder 66 and the shaft 64 constitute a telescopic mechanism. This telescopic mechanism is the same as the above-described telescopic mechanisms in the Z-direction moving part 28 of the sealing head and the Z-direction moving part 48 of the first cooling head. The lower end of the shaft 64 is attached to the central part of the second cooling head 16. When the shaft 64 expands and contracts with respect to the cylinder 66, the position of the second cooling head 16 in the Z direction changes. In this way, the Z-direction moving part 68 of the second cooling head raises and lowers the second cooling head 16 with respect to the film 2. In the present embodiment, the Z-direction moving part 68 of the second cooling head further includes a load sensor 67 for detecting the pressing pressure.

[0044] The X-direction moving part 70 moves the sealing head 12 and the first cooling head 14 in the X direction, which is the longitudinal direction of the housing 11. In this example, the X-direction moving part 70 selectively switches between two positions: a position where the sealing head 12 faces the sealing part 6 of the film 2 and a position where the first cooling head 14 faces the sealing part 6 of the film 2 by integrally moving the sealing head 12 and the first cooling head 14 in the X direction.

[0045] The X-direction moving part 70 includes, as an example, two ball screws 72a and 72b parallel to each other, first moving blocks 74a and 74b screwed onto the ball screws 72a and 72b, second moving blocks 76a and 76b, a guide rail (not shown), and stepping motors 75a and 75b.

[0046] Each of the cylinders 26a and 26b of the seal head Z-direction moving part 28 is fixed to each of the first moving blocks 74a and 74b. Also, each of the cylinders 46a and 46b of the first cooling head Z-direction moving part 48 is fixed to each of the second moving blocks 76a and 76b. The first moving blocks 74a and 74b and the second moving blocks 76a and 76b are attached in a state movable in the X direction to a guide rail (not shown) provided on the ceiling of the housing 11, for example. Both ends of each of the ball screws 72a and 72b are rotatably supported by a pair of shaft support parts 73a and 73b, respectively, attached to opposite wall surfaces perpendicular to the x direction of the housing 11. And one end of each of the ball screws 72a and 72b is connected to the drive shafts of the stepping motors 75a and 75b that rotate forward and backward. Therefore, when the ball screws 72a and 72b are rotated by the stepping motors 75a and 75b, the first moving blocks 74a and 74b and the second moving blocks 76a and 76b move forward and backward in the X direction. Thereby, the seal head 12 and the first cooling head 14 linearly move in the X direction.

[0047] As described above, the X-direction moving unit 70 selectively opposes the sealing head 12 and the first cooling head 14 to the film 2 by integrally moving the sealing head 12 and the first cooling head 14 in the X direction. The position where the sealing head 12 faces the sealing portion 6 of the film 2 is the position shown in FIG. 1, and this position corresponds to the processing position X1 in FIG. 4. Since the sealing head 12 and the first cooling head 14 move integrally in the X direction, the interval in the X direction is constant. As shown in FIG. 1, when the sealing head 12 is located at the processing position X1, the first cooling head 14 is located at the retracted position X2 that retracts from the processing position X1. Then, when the first cooling head 14 moves from the retracted position X2 to the processing position X1 facing the sealing portion 6 of the film 2, the sealing head 12 moves to the second retracted position X2 on the side opposite to the first retracted position X0 with the processing position X1 interposed therebetween. In this way, the sealing head 12 is movable between the processing position X1 for sealing the films 2a and 2b sandwiching the article 1 and the first retracted position X0. Further, the first cooling head 14 is movable between the second retracted position X2 and the processing position X1.

[0048] The X-direction moving unit 70 is not limited to the configuration using the above ball screw, and other known linear movement mechanisms such as a rack and pinion may be applied.

[0049] On the other hand, the cylinder 66 of the second cooling head Z-direction moving unit 68 is fixed to a fixed block 84 fixed to a support shaft 82 installed in parallel with the ball screws 72a and 72b. That is, unlike the first cooling head 14, the second cooling head 16 does not move in the horizontal direction including the X direction and is only movable in the Z direction. In this way, in this heat sealing device 10, although the second cooling head 16 is not provided with a horizontal movement mechanism, it may be provided with a horizontal movement mechanism.

[0050] As shown in FIG. 4, in the present embodiment, the control unit 90 is incorporated in the control device 100, and the control device 100 includes a memory 92. The control unit 90 comprehensively controls each part of the heat sealing device 10. The control unit 90 includes a processor. An example of the processor is a CPU (Central Processing Unit) that performs various controls by executing a program. The CPU functions as a control unit 90 having a movement control unit 94 and a temperature control unit 96 by executing a program. The memory 92 is an example of a memory connected to or incorporated in the CPU as a processor. For example, a control program is stored in the memory 92. The control unit 90 is realized by the CPU executing the control program. The control unit 90 has a movement control unit 94 and a temperature control unit 96. These are realized by the CPU executing the control program.

[0051] In addition to the control program, the memory 92 stores setting information that is preset for the control unit 90 to perform various controls. As the setting information, information necessary for performing movement control in the X direction of each of the seal head 12 and the first cooling head 14 and movement control in the Z direction of each of the seal head 12, the first cooling head 14, and the second cooling head 16 is recorded. Further, in the present embodiment, the setting information also includes information necessary for controlling the temperature of each of the seal head 12, the first cooling head 14, and the second cooling head 16.

[0052] The movement control unit 94 includes an X-direction movement control unit 94a, a seal head Z-direction movement control unit 94b, a first cooling head Z-direction movement control unit 94c, and a second cooling head Z-direction movement control unit 94d. The movement control unit 94 drives and controls each of the X-direction movement unit 70, the Z-direction movement unit 28 of the seal head 12, the Z-direction movement unit 48 of the first cooling head 14, and the Z-direction movement unit 68 of the second cooling head 16 by the respective movement control units 94a to 94d.

[0053] The X-direction movement control unit 94a drives the stepping motors 75a and 75b of the X-direction movement unit 70. In the sealing process, the X-direction movement control unit 94a controls the movement of the sealing head 12 and the first cooling head 14 in the X direction so that the sealing head 12 is positioned at the processing position X1 and the first cooling head 14 is positioned at the second retracted position X2. Also, after the sealing process, for the cooling process of cooling the sealed portion, the X-direction movement control unit 94a controls the movement of the sealing head 12 and the first cooling head 14 in the X direction so that the sealing head 12 is retracted from the processing position X1 to the first retracted position X0 and the first cooling head 14 is positioned from the second retracted position X2 to the processing position X1.

[0054] The sealing head Z-direction movement control unit 94b drives the cylinders 26a and 26b to expand and contract the shafts 24a and 24b to raise and lower the sealing head 12. In the sealing process, with the sealing head 12 positioned at the processing position X1, the cylinders 26a and 26b are driven to extend the shafts 24a and 24b, and the sealing surface 20 is pressed against the sealed portion 6 of the laminated films 2a and 2b. The sealing head 12 is heated by a heater, and the sealed portion 6 is heat-welded by pressing the sealing surface 20 against the sealed portion 6 of the films 2a and 2b.

[0055] The first cooling head Z-direction movement control unit 94c drives the cylinders 46a and 46b to expand and contract the shafts 44a and 44b to raise and lower the first cooling head 14. After the sealing process, with the first cooling head 14 positioned at the processing position X1, the cylinders 46a and 46b are driven to extend the shafts 44a and 44b, and the pressing surface 40 is pressed against the welded sealed portion 6. The first cooling head 14 is cooled by a cooling element, and the sealed portion 6 is cooled by pressing the pressing surface 40 against the sealed portion 6.

[0056] The second cooling head Z-direction movement control unit 94d raises and lowers the second cooling head 16 by driving the cylinder 66 to expand and contract the shaft 64. Before the sealing process, with the second cooling head 16 positioned at the processing position X1, the cylinder 66 is driven to extend the shaft 64, and the pressing surface 60 is pressed against the article 1 through the film 2b. The second cooling head 16 is cooled by a cooling element, and when the pressing surface 60 is pressed against the article-side region 8, the article 1 is cooled through the film 2b.

[0057] Also, the control unit 90 controls the temperatures of the sealing head 12, the first cooling head 14, and the second cooling head 16 to preset temperatures by the temperature control unit 96.

[0058] The temperature control unit 96 includes a sealing head temperature control unit 96a, a first cooling head temperature control unit 96b, and a second cooling head temperature control unit 96c. The sealing head temperature control unit 96a controls the temperature of the sealing head 12. The first cooling head temperature control unit 96b controls the temperature of the first cooling head 14. The second cooling head temperature control unit 96c controls the temperature of the second cooling head 16.

[0059] The sealing head temperature control unit 96a compares the temperature of the sealing head 12 detected by the temperature sensor 21 provided on the sealing head 12 with the preset temperature of the sealing head 12 held as setting information in the memory 92, adjusts the heating heater, and controls the temperature of the sealing head 12 to reach the preset temperature. The preset temperature of the sealing head 12 is, for example, about 100°C to 200°.

[0060] The first cooling head temperature control unit 96b compares the temperature of the first cooling head 14 detected by the temperature sensor 41 provided on the first cooling head 14 with the preset temperature of the first cooling head 14 held as setting information in the memory 92, adjusts the cooling element, and controls the temperature of the first cooling head 14 to reach the preset temperature.

[0061] The second cooling head temperature control unit 96c compares the temperature of the second cooling head 16 detected by the temperature sensor 61 provided in the second cooling head 16 with the set temperature of the second cooling head 16 held as setting information in the memory 92, adjusts the cooling element, and controls the temperature of the second cooling head 16 to reach the set temperature.

[0062] Note that the set temperatures of the first cooling head 14 and the second cooling head 16 are, for example, predetermined constant temperatures, and specifically, can be set to a predetermined temperature of 20°C or lower.

[0063] Next, the heat sealing procedure using the heat sealing device 10 will be described with reference to FIGS. 7 to 9. FIGS. 7 and 8 are process diagrams, and FIG. 9 is a timing chart showing the movement timings of the seal head 12, the first cooling head 14, and the second cooling head 16 by the movement mechanism 18.

[0064] First, a laminate in which the article 1 is sandwiched between the films 2a and 2b is set on the pallet 5 for heat sealing processing (step S1).

[0065] Next, the laminate is inserted into the heat sealing device 10 and set at the processing position (step S2). At this time, as the initial position, the seal head 12 and the second cooling head 16 are arranged at the processing position X1, and the first cooling head 14 is arranged at the second retracted position X2.

[0066] At time t1, the second cooling head 16 is lowered and brought into contact with the article side region 8 of the film 2b (step S3). Thereby, the second cooling head 16 is pressed against the article 1 through the film 2b to cool the article 1. By cooling the article 1, heat damage to the article 1 due to radiant heat from the seal head 12 is suppressed.

[0067] With the second cooling head 16 in contact with the film 2b and the article 1 being cooled, at time t2, the seal head 12 is lowered, the seal head 12 is brought into contact with the seal portion 6, and the film 2a and the film 2b are heat welded (step S4).

[0068] After heat welding, at time t3, raise the seal head 12 to make the seal head 12 in a non-contact state with the seal part 6 (step S5).

[0069] Next, retract the seal head 12 from the processing position X1 to the first retracted position X0, and move the first cooling head 14 from the second retracted position X2 to the processing position X1 (step S6).

[0070] With the first cooling head 14 set at the processing position X1, lower the first cooling head 14 at time t4 to contact the welded seal part 6 and cool the seal part 6 (step S7).

[0071] After cooling the seal part 6, at time t5, raise the first cooling head 14 and the second cooling head 16 to make the first cooling head 14 in a non-contact state with the seal part 6 (step S8).

[0072] The heat sealing process in the heat sealing device 10 is performed as described above.

[0073] The heat sealing device 10 of the present embodiment includes, in addition to the first cooling head 14 that cools the seal part 6, a second cooling head 16 that cools the article side region 8 on the article side of the film 2 relative to the seal part 6. Therefore, while improving the heat sealing throughput, heat damage to the article 1 packaged by the film 2 can be suppressed.

[0074] In the present embodiment, the moving mechanism 18 is configured to move the seal head 12, the first cooling head 14, and the second cooling head 16 relative to the film 2. However, the moving mechanism 18 may move the article 1 and the film 2 relative to the seal head 12, the first cooling head 14, and the second cooling head 16. Further, the moving mechanism 18 may be configured to move both of them together.

[0075] Thus, since the heat-sealing device 10 includes the moving mechanism 18 and the control unit 90 that relatively move each of the seal head 12, the first cooling head 14, and the second cooling head 16 and the films 2a and 2b, it is easy to control heat welding and cooling.

[0076] The control unit 90 preferably controls each of the seal head 12, the first cooling head 14, the second cooling head 16, and the moving mechanism 18 such that after starting the cooling of the article side region 8 by bringing the second cooling head 16 into contact with the article side region 8 by the moving mechanism 18, the heat welding of the seal portion 6 is started by bringing the seal head 12 into contact with the seal portion 6 by the moving mechanism 18. Since the cooling of the article side region 8 by the second cooling head 16 is started prior to the heat welding, the heat damage received by the article 1 due to the heat of the seal head 12 can be reduced as compared with the case where the heat welding of the seal portion 6 and the cooling of the article side region 8 are started simultaneously by bringing the seal head 12 and the second cooling head 16 into contact with the films 2a and 2b at the same time. However, the second cooling head 16 and the seal head 12 may be lowered simultaneously to start the cooling of the article side region and the welding of the seal portion substantially simultaneously.

[0077] In the above process, although the first cooling head 14 and the second cooling head 16 are raised simultaneously, they may be raised sequentially. That is, the first cooling head 14 may be raised first and then the second cooling head 16 may be raised, or the second cooling head 16 may be raised first and then the first cooling head 14 may be raised.

[0078] In the present embodiment, the control unit 90 controls each of the seal head 12, the first cooling head 14, the second cooling head 16, and the moving mechanism 18 such that after the heat welding by the seal head 12, the seal head 12 is retracted from the seal portion 6 by the moving mechanism 18 and the first cooling head 14 is brought into contact with the seal portion 6 by the moving mechanism 18. By providing such a control unit 90, the heat-sealed seal portion 6 can be rapidly cooled, so that the throughput of heat sealing can be improved.

[0079] Further, as in the present embodiment, it is preferable that the control unit 90 controls each of the seal head 12, the first cooling head 14, the second cooling head 16, and the moving mechanism 18 so as to continue cooling the article side region 8 by the second cooling head 16 from the start of heat welding of the seal portion 6 by the seal head 12 until the cooling of the seal portion 6 by the first cooling head 14 is completed. In order to continue cooling by the second cooling head 16 from the start of heat welding until the cooling by the first cooling head 14 is completed, compared with the case where the cooling by the second cooling head 16 is stopped before the cooling by the first cooling head 14 is completed, the cooling effect on the article 1 can be continued, so that the thermal damage received by the article 1 can be reduced.

[0080] In the heat seal device 10 of the present embodiment, the first cooling head 14 and the second cooling head 16 each include temperature sensors 41, 62 and cooling elements, and the control unit 90 controls them to a preset temperature. However, the first cooling head 14 only needs to be able to cool the seal portion 6 after heat welding, and may not include the temperature sensor 41 and the cooling element, or may have a configuration including only the cooling element. Similarly, the second cooling head 16 does not need to include the temperature sensor 61 and the cooling element as long as it can suppress damage to the article 1 caused by the heat from the radiant heat from the seal head 12, and may also have a configuration including only the cooling element.

[0081] In this heat sealing device 10, it is preferable that the second cooling head Z-direction movement control unit 94d controls the pressing pressure when the second cooling head 16 contacts the article side region. In this example, it controls the pressing pressure when the second cooling head 16 presses against the article 1. In the present embodiment, the second cooling head Z-direction movement unit 68 further includes a load sensor 67 that detects the pressing pressure, and the second cooling head Z-direction movement control unit 94d can control the pressing pressure based on the signal from the load sensor 67. By controlling the pressing pressure when the second cooling head 16 contacts the article side region, the driving amount of the cylinder 66 can be controlled so that the pressing pressure on the article 1 when contacting does not exceed a predetermined set value. Thereby, an excessive pressing pressure on the article 1 can be suppressed, and damage to the article 1 can be suppressed.

[0082] Note that not only the second cooling head Z-direction movement control unit 94d but also the seal head Z-direction movement control unit 94b preferably controls the pressing pressure when the seal head 12 contacts the seal portion 6. In this case, it is only necessary that the seal head Z-direction movement unit 28 includes a load sensor and the seal head Z-direction movement control unit 94b is configured to control the pressing pressure based on the signal from the load sensor. Similarly, it is preferable that the first cooling head Z-direction movement control unit 94c controls the pressing pressure when the first cooling head 14 contacts the seal portion 6. In this case, it is only necessary that the first cooling head Z-direction movement unit 48 includes a load sensor and the first cooling head Z-direction movement control unit 94c is configured to control the pressing pressure based on the signal from the load sensor.

[0083] In the above embodiment, as shown in FIG. 6, when cooling the article-side region 8, the pressing surface 60 of the second cooling head 16 that presses the article-side regions 8 of the films 2a and 2b is disposed at a position facing the entire surface of the article 1. As a result, the entire surface of the article 1 can be cooled, so that thermal damage to the article 1 can be effectively suppressed. Therefore, it is particularly effective when packaging an article that is sensitive to heat. FIG. 10 is a view showing an enlarged view of the end portion of the article 1 and the end portions of the seal head 12 and the second cooling head 16. As shown in FIG. 10, in the present embodiment, the position of the end surface 16e on the seal head 12 side of the pressing surface 60 of the second cooling head 16 that presses the article-side regions of the films 2a and 2b coincides with the position of the end surface 1e on the seal head 12 side of the article 1. In the article 1, the end surface 1e side closest to the seal head 12 is likely to receive thermal damage. However, in this example, since the pressing surface 60 of the second cooling head 16 is disposed facing the entire surface of the article 1 and the end portion of the article 1 is cooled by the second cooling head 16, the effect of suppressing thermal damage is high.

[0084] However, if the second cooling head 16 can cool at least a part of the article-side region 8 on the article 1 side rather than the seal portion 6, the effect of suppressing thermal damage to the article can be obtained. That is, the technique of the present disclosure includes a case where the pressing surface 60 of the second cooling head 16 is not at a position facing the entire surface of the article 1.

[0085] For example, as shown in FIG. 11, even if the end surface 16e of the second cooling head 16 is farther from the seal head 12 than the end surface 1e of the article 1, that is, even if D>d1, it does not matter. However, from the viewpoint of efficiently suppressing thermal damage, the difference D-d1 between the distance D between the second cooling head 16 and the seal head 12 and the distance d1 between the end surface 1e of the article 1 and the seal head 12 is preferably small.

[0086] Incidentally, as shown in FIG. 12, it is particularly preferable that D < d1, that is, the end face 16e of the second cooling head 16 is located closer to the seal head 12 side than the end face 1e of the article 1. That is, when cooling the article-side region 8, it is preferable that the end position on the seal head 12 side of the pressing surface 60 that presses the article-side regions 8 of the films 2a and 2b by the second cooling head 16 is located closer to the seal head 12 side than the end position on the seal head 12 side of the article 1. When cooling the article-side region, since the end position on the seal head 12 side of the pressing surface 60 of the second cooling head 16 is located closer to the seal head 12 side than the end position on the seal head 12 side of the article 1, heat damage to the article can be more effectively suppressed.

[0087] The design modification examples of the second cooling head 16 will be described below.

[0088] FIG. 13 is a plan view showing the positional relationship between the second cooling head 16A of Design Modification Example 1 and the seal head 12 and the article 1, and the following figure is a cross-sectional view taken along line 13B-13B. As shown in FIG. 13, the second cooling head 16A has a rectangular frame shape similar to that of the seal head 12. When cooling the article-side region 8, the pressing surface 60A that presses the article-side regions 8 of the films 2a and 2b by the second cooling head 16 may be positioned so as to surround the outer periphery of the article 1 without facing the article 1. Since the pressing surface 60A of the second cooling head 16A is located in the article-side region 8 on the article side of the seal portion 6, the propagation of radiant heat from the seal head 12 disposed in the seal portion 6 to the article side can be suppressed. In this way, even when the article 1 is not directly cooled by the second cooling head 16A, the article can be indirectly cooled by disposing the second cooling head 16A on the outer periphery of the article 1, and heat damage to the article 1 can be suppressed.

[0089] FIG. 14 is a plan view showing the positional relationship between the second cooling head 16B of Design Modification Example 2 and the seal head 12 and the article 1, and the following figure is a cross-sectional view taken along line 14B-14B. As shown in FIG. 14, the second cooling head 16B has a rectangular frame shape similar to that of the seal head 12. When cooling the article-side region 8, it is preferable that the pressing surface 60B of the second cooling head 16B that presses the article-side regions 8 of the films 2a and 2b is disposed at a position facing at least the outer peripheral edge of the article 1. Since the pressing surface 60B of the second cooling head 16B is disposed at a position facing at least the outer peripheral edge of the article 1, heat damage to the article 1 can be suppressed as compared with the case where it does not face the article 1.

[0090] FIG. 15 is a view showing an enlarged view of the end portion of the article 1, the seal head 12, and the end portion of the second cooling head 16C of Design Modification Example 3. As shown in FIG. 15, the second cooling head 16C has a stepped portion 16f at the end. That is, on the seal head 12 side, the pressing surface 60C of the second cooling head 16C protrudes more from the article 1 side than the article 1 side with respect to the position facing the outer peripheral edge of the article 1 as a reference S. Since on the seal head 12 side, the pressing surface 60C of the second cooling head 16C protrudes more from the article 1 side than the article 1 side with respect to the position facing the outer peripheral edge of the article 1 as a reference S, radiant heat that wraps around from below the second cooling head 16C from the seal head 12 can also be suppressed. Therefore, a higher heat damage suppression effect can be obtained as compared with the case where the end portion of the pressing surface 60C does not protrude.

[0091] FIG. 16 is a view showing an enlarged view of the end portion of the article 1, the seal head 12, and the end portion of the second cooling head 16D in Design Modification Example 4. As shown in FIG. 16, the second cooling head 16D has a tapered portion 16g whose protruding amount increases as it approaches the end portion. That is, similar to the second cooling head 16C, in the second cooling head 16D, the pressing surface 60D has a position where the side of the seal head 12 protrudes more from the article 1 side than the outer peripheral edge of the article 1 with respect to the reference S. Therefore, also in the second cooling head 16D, the radiant heat that wraps around from below the second cooling head 16D from the seal head 12 can be suppressed, so that a higher heat damage suppression effect can be obtained as compared with the case where the end portion of the pressing surface 60D does not protrude.

[0092] In each of the above embodiments, as the hardware structure of a processing unit (Processing Unit) that executes various processes such as the control unit 90, the movement control unit 94, and the temperature control unit 96, the following various processors (Processor) can be used. As described above, among various processors, in addition to a CPU which is a general-purpose processor that executes software and functions as various processing units, a programmable logic device (Programmable Logic Device: PLD) which is a processor whose circuit configuration can be changed after manufacturing such as an FPGA (Field Programmable Gate Array), and a dedicated electric circuit etc. which is a processor having a circuit configuration specifically designed to execute a specific process such as an ASIC (Application Specific Integrated Circuit) are included.

[0093] One processing unit may be constituted by one of these various processors, or may be constituted by a combination of two or more processors of the same type or different types (for example, a combination of a plurality of FPGAs, and / or, a combination of a CPU and an FPGA). Further, a plurality of processing units may be constituted by one processor.

[0094] As an example of configuring a plurality of processing units with one processor, there is a form in which one processor is configured by a combination of one or more CPUs and software, and this processor functions as a plurality of processing units. Second, there is a form in which a processor that realizes the functions of an entire system including a plurality of processing units with one IC (Integrated Circuit) chip is used, as represented by a System On Chip (SoC) or the like. As described above, various processing units are configured using one or more of the above various processors as a hardware structure.

[0095] Furthermore, as a hardware structure of these various processors, more specifically, an electrical circuit (circuitry) combining circuit elements such as semiconductor elements can be used.

[0096] From the above description, the technology described in the following appended claims can be understood. [Appended Claim 1] A heat sealing device for sealing a film for packaging an article, the film being arranged in a state where the article is sandwiched and a part thereof is overlapped around the article, by heat welding, A sealing head for heat welding a sealing portion to be sealed in the film, A first cooling head for cooling the sealing portion after heat welding by the sealing head, A second cooling head for cooling at least a part of an article-side region on the article side of the film with respect to the sealing portion, A moving mechanism for relatively moving each of the sealing head, the first cooling head, and the second cooling head and the film, And a processor, The processor is a heat sealing device configured to control each part of the sealing head, the first cooling head, the second cooling head, and the moving mechanism.

[0097] The disclosure of Japanese Patent Application No. 2021-026600 filed on February 22, 2021 is incorporated herein by reference in its entirety. All documents, patent applications, and technical standards described in this specification are hereby incorporated by reference into this specification to the same extent as if each individual document, patent application, and technical standard were specifically and individually indicated to be incorporated by reference.

Claims

1. A heat sealing device for sealing a film for packaging an article by heat welding the film that sandwiches the article and is arranged with a part thereof overlapped around the article, a sealing head for heat welding a seal portion to be sealed in the film, a first cooling head for cooling the seal portion after heat welding by the sealing head, a second cooling head separate from the first cooling head for cooling at least a part of an article-side region of the film on the article side with respect to the seal portion, a moving mechanism for relatively moving the sealing head, the first cooling head, and the second cooling head with respect to the film, a control unit for controlling each part of the sealing head, the first cooling head, the second cooling head, and the moving mechanism, comprising: wherein the control unit continues cooling of the article-side region by the second cooling head from the start of heat welding of the seal portion by the sealing head until the cooling of the seal portion by the first cooling head is completed. A heat sealing device.

2. The heat sealing device according to claim 1, wherein the control unit starts cooling of the article-side region by bringing the second cooling head into contact with the article-side region by the moving mechanism, and then starts heat welding of the seal portion by bringing the sealing head into contact with the seal portion by the moving mechanism.

3. The heat sealing device according to claim 2, wherein after heat welding by the sealing head, the control unit retracts the sealing head from the seal portion by the moving mechanism and brings the first cooling head into contact with the seal portion by the moving mechanism.

4. The heat sealing device according to any one of claims 1 to 3, wherein the control unit controls the temperature of at least one of the first cooling head and the second cooling head to a preset temperature.

5. The heat sealing device according to claim 4, wherein the preset temperature is 20°C or lower.

6. The heat sealing device according to any one of claims 1 to 5, wherein the control unit controls the pressing pressure on the contact region when the second cooling head is brought into contact with the article-side region.

7. When cooling the article-side region, in the heat-sealing device according to any one of claims 1 to 6, the end position on the seal head side of the pressing surface that presses the article-side region of the film by the second cooling head is located closer to the seal head side than the end position on the seal head side of the article.

8. When cooling the article-side region, in the heat-sealing device according to any one of claims 1 to 7, the pressing surface that presses the article-side region of the film by the second cooling head is disposed at a position facing at least the outer peripheral edge of the article.

9. When cooling the article-side region, in the heat-sealing device according to claim 8, the pressing surface that presses the article-side region of the film by the second cooling head is disposed at a position facing the entire surface of the article.

10. In the heat-sealing device according to claim 8 or 9, the seal head side of the pressing surface protrudes more from the article side than the article side with reference to the position facing the outer peripheral edge of the article.

11. When the width of the seal head is LH and the distance between the seal head and the second cooling head is D, the relationship between D and LH is LH / 1000 < D < 10LH in the heat-sealing device according to any one of claims 1 to 9.

12. When the width of the seal head is LH and the width of the first cooling head is LC, the relationship between LH and LC is LH / 2 < LC in the heat-sealing device according to any one of claims 1 to 10.

13. The seal portion is provided in a manner surrounding the entire circumference of the article, and the seal head also has a frame shape corresponding to the shape of the seal portion in the heat-sealing device according to any one of claims 1 to 12.

14. The moving mechanism does not have a function of moving the film, and includes a mechanism for horizontally moving the seal head and the first cooling head, and a mechanism for moving the seal head, the first cooling head, and the second cooling head up and down, in the heat-sealing device according to claim 1.

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