Heat sealing device and bag making machine

Abstract

The present invention relates to a heat sealing device and a bag making machine. The heat sealing device includes at least two main force applying members and a sub force applying member. These force applying members are arranged between a slider and a first heat sealing member so as to apply a force to the first heat sealing member toward the second heat sealing member when a constituent member of a bag is clamped by the first heat sealing member and the second heat sealing member. The main force applying members are arranged on a straight line in a first horizontal direction. The sub force applying member is arranged offset from the main force applying members in a second horizontal direction which is at right angles to the first horizontal direction. The heat sealing device is configured to be able to adjust the force applied to the first heat sealing member by the sub force applying member.

Description

TECHNICAL FIELD

[0001] The present application relates to a heat sealing device for a bag making machine. In addition, the present application relates to a bag making machine including the heat sealing device. BACKGROUND

[0002] The bag making machines disclosed in Patent Literature 1 and Patent Literature 2 include a heat sealing device that seals a constituent component of a bag before forming (cross-cutting process) of the bag. The constituent component of the bag is, for example, a web-shaped main body portion, or a web-shaped or sheet-shaped gusset portion (side gusset portion, bottom gusset portion, top gusset portion). The heat sealing device seals two web-shaped main body portions to each other, or seals a gusset portion to a main body portion. The direction of the sealing is generally a width direction or a length direction of the web-shaped main body portion.

[0003] The direction of the sealing is sometimes an oblique direction with respect to the width direction and the length direction of the web-shaped main body portion. For example, the heat sealing device disclosed in Patent Literature 3 seals a gusset portion to a main body portion, thereby forming an oblique sealing portion in a V-shape.

[0004] Such a heat sealing device seals a constituent component of a bag by sandwiching the constituent component of the bag with a first heat sealing member and a second heat sealing member that are heated. Therefore, at least the first heat sealing member includes a surface that has a shape of a sealing portion to be formed and is pressed against the constituent component of the bag.

[0005] The heat sealing device includes at least two force applying members that apply a force to the first heat sealing member toward the second heat sealing member when the constituent component of the bag is sandwiched with the first heat sealing member and the second heat sealing member. The at least two force applying members are arranged on one straight line in a horizontal direction with a space between the force applying members. The force applied by the force applying members is applied to the constituent component of the bag via the first heat sealing member. The force applying members are springs or cylinders (see Patent Literature 1 and Patent Literature 2).

[0006] If the force is applied to the constituent component of the bag uniformly, the completion of the sealing portion becomes good. Therefore, the center of the surface of the first heat sealing member can be located on an action line (extending in the up-down direction) of a resultant force of the forces applied by the force applying members. If in this state, uniform sealing pressure is applied to the entire area of the surface, thereby a high-quality sealing can be obtained.

[0007] According to the shape, size, design of the bag, and the like of the bag to be manufactured, the shape or position of the sealing portion must be changed at times. In the case, the first heat-sealing member is changed to a different shape, or the position of the first heat-sealing member is changed. However, due to such a change, the center of the surface of the first heat-sealing member sometimes deviates from the action line of the resultant force of the force applying members. In particular, the center of the surface deviates from the arrangement line of the force applying members in many cases. Due to the deviation, the application of the force becomes uneven, and the completion of the sealing portion can be deteriorated.

[0008] Prior Art Documents

[0009] Patent Documents

[0010] Patent Document 1: Japanese Patent Laid-Open No. 2018-76090

[0011] Patent Document 2: WO2019 / 225266

[0012] Patent Document 3: WO2018 / 012542 SUMMARY

[0013] The present application aims to provide a heat-sealing device capable of adjusting the action line of the total applied force of the force applying members in the horizontal direction at right angles to the arrangement line of the main force applying members, and a bag making machine including the heat-sealing device.

[0014] According to an embodiment of the present application, a heat-sealing device for heat-sealing constituent components of a bag can be provided, the heat-sealing device including:

[0015] a plurality of beams arranged at intervals in a first horizontal direction;

[0016] a cross beam supported by the plurality of beams and extending in the first horizontal direction between the plurality of beams;

[0017] a slider configured to be movable up and down with respect to the cross beam;

[0018] a first heat-sealing member movable up and down with the slider;

[0019] a second heat-sealing member facing the first heat-sealing member in the up and down direction;

[0020] an up and down moving mechanism for moving the plurality of beams and the cross beam up and down to bring the slider and the first heat-sealing member closer to and farther away from the second heat-sealing member;

[0021] at least two main force applying members located between the slide and the cross beam, for applying force to the slide and the first heat seal member toward the second heat seal member when the constituent components of the bag are clamped by the first heat seal member and the second heat seal member; and

[0022] a sub force applying member located between the slide and the cross beam, for applying force to the slide and the first heat seal member toward the second heat seal member when the constituent components of the bag are clamped by the first heat seal member and the second heat seal member,

[0023] the at least two main force applying members are arranged in a straight line in the first horizontal direction,

[0024] the sub force applying member is arranged offset from the at least two main force applying members in a second horizontal direction that is at right angles to the first horizontal direction,

[0025] the heat seal device is configured to be able to adjust the force applied by the sub force applying member to the first heat seal member.

[0026] the heat seal device can be configured to be able to adjust the sub force applying member to a state in which the sub force applying member does not apply force to the first heat seal member when the constituent components of the bag are clamped by the first heat seal member and the second heat seal member.

[0027] the first heat seal member can include:

[0028] a base; and

[0029] a seal plate that is detachably attached to the base.

[0030] the seal plate can include a protruding portion having a surface that faces the second heat seal member when the seal plate is attached to the base.

[0031] the heat seal device can be configured to perform heat sealing by clamping the constituent components of the bag with the seal plate and the second heat seal member, forming a seal portion having the shape of the surface of the protruding portion.

[0032] the first heat seal member can be configured such that the seal plate can be attached to the base at different positions with respect to the second horizontal direction.

[0033] the sub force applying member can be a spring or a gas cylinder.

[0034] the at least two main force applying members can be springs or gas cylinders.

[0035] According to another embodiment of the present application, a bag making machine including the heat seal device can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1A This is a schematic plan view of an example bag-making machine. Figure 1B yes Figure 1A Front view, Figure 1C yes Figure 1A Side view.

[0037] Figure 2A yes Figure 1A A magnified plan view of region S. Figure 2B yes Figure 2A The back view, Figure 2C This is a partial plan view of another example of a second folding device.

[0038] Figure 3 It is a detailed representation Figure 1A The image shows a bag.

[0039] Figure 4 This is a schematic plan view of an illustrative heat sealing device.

[0040] Figure 5 yes Figure 4 Front view of the heat sealing device.

[0041] Figure 6A yes Figure 5 Longitudinal section view of the location of the main force-applying component. Figure 6B yes Figure 5 A longitudinal section view of the location of the secondary force-applying component.

[0042] Figure 7 This is a diagram illustrating an example of a sealing plate.

[0043] Figure 8 yes Figure 5 Longitudinal section view of the location of the adjusting bolt.

[0044] Figure 9 Explain the heat sealing process.

[0045] Figure 10 Explain the heat sealing process.

[0046] Figure 11 Explain the heat sealing process.

[0047] Figure 12 It indicates the planar positional relationship of the bag's constituent components, configuration lines, protrusions, and lines of action.

[0048] Figure 13 It indicates the planar positional relationship of the bag's constituent components, configuration lines, protrusions, and lines of action.

[0049] Figure 14A , Figure 14B Explain the adjustment of the line of action towards the core of the diagram. Detailed Implementation

[0050] Hereinafter, embodiments of this application will be described with reference to the accompanying drawings.

[0051] exist Figures 1A-1C The diagram illustrates an illustrative bag-making machine. The machine sequentially manufactures bags 10 from a web 1. The web 1 is continuously drawn from the original roll 1' along its length direction (its continuous direction) at a constant speed and folded in half by a first folding device 30. The first folding device 30 includes a triangular plate 300 and a set of clamping rollers 301. The web 1 is folded along its length centerline during transport by the triangular plate 300 and the clamping rollers 301. Figure 1A The symbol 100 represents the bend caused by folding the web 1. Figure 1A Symbols 101 and 102 represent the two edges of the web 1 that are flush with each other by folding the web 1 in half.

[0052] Subsequently, the folded fabric 1 is appropriately switched from continuous conveying to intermittent conveying by the agitation device 31, which includes a agitation roller. Furthermore, a conveying device 32, including a set of conveying rollers, is provided in the downstream section of the bag-making machine to intermittently convey the fabric 1 along its length. The conveying direction of the fabric 1 is indicated by the symbol X1.

[0053] Subsequently, the web 1 is further folded by the second folding device 33, such that the web 1 forms two web-shaped main body portions 11 and 12, and a web-shaped corner support portion 13 folded between these main body portions 11 and 12. The main body portions 11, 12, and corner support portion 13 are constituent components of the bag 10.

[0054] The second folding device 33 includes a set of expanding rollers 332 disposed downstream of a set of guide rollers 330 and upstream of a set of guide rollers 331. Figure 1B The folded web 1 is spread out by the expansion roller 332 in the section from the guide roller 330 to the guide roller 331.

[0055] Figure 2A yes Figure 1A An enlarged plan view of region S. The second folding device 33 also includes a forming plate 333 located downstream of the expansion roller 332 and upstream of the guide roller 331. Figure 2B This is a back view of region S. The forming plate 333 has a triangular shape. The forming plate 333 is configured to abut against the portion containing the bending edge 100 from the outside. The forming plate 333 faces downstream and narrows towards the web 1, with one of its tops 3330 becoming the downstream end of the forming plate 333 and entering the web 1, approaching the guide roller 331, and abutting against the bending edge 100 of the web 1.

[0056] With the conveyance of the web 1, the portion including the bent edge 100 is folded back along the bent edge 100 in the opposite direction in such a manner as to enter between the two layers of the web 1 by the forming plate 333. Then, in this state, the web 1 is passed between the set of guide rollers 331.

[0057] Thus, the portion including the bent edge 100 is folded into between the two layers of the web 1, as a result of which the gusset portion 13 is formed in a web shape, and the two layers of the web 1 become the two body portions 11, 12 in a web shape. The bent edge 100 becomes the inner side edge of the gusset portion 13. Figure 2A The symbol 103, the symbol 104 are the end edges of the body portions 11, 12, and are the outer side edges of the gusset portion 13, that is, the boundary edges of the gusset portion 13 and the body portions 11, 12. Hereinafter, the web 1 is conveyed in the folded state as described above.

[0058] Further, the amount of folding of the gusset portion 13 into the body portions 11, 12, that is, the gusset depth, can be adjusted using the position of the forming plate 333.

[0059] Figure 2C An alternative example of the second folding device 33 is shown. The second folding device 33 can fold the portion including the bent edge 100 into by a known folding plate 334 and an inner side guide plate (not shown) instead of the forming plate 333. In this case, the amount of folding of the gusset portion 13 can be adjusted and determined using the position of the folding plate 334.

[0060] Referring again to Figure 1A , Figure 1B , the bag making machine includes a heat sealing device 4 provided downstream of the second folding device 33 for heat sealing the gusset portion 13 to the body portions 11, 12 to form a seal portion 14 Figure 3 ) at each intermittent conveyance of the web 1. The structure of the heat sealing device 4 will be described later.

[0061] The bag making machine includes a transverse sealing device 34 provided downstream of the heat sealing device 4 for sealing the body portions 11, 12 and the gusset portion 13 in the form of heat sealing or ultrasonic sealing in the width direction of the body portions 11, 12 at each intermittent conveyance of the web 1 to form a transverse seal portion 15 Figure 3 ). In the embodiment, the transverse sealing device 34 heat seals the constituent components 11, 12, 13 of the bag, for example, using two sets of heat sealing bars.

[0062] The bag-making machine also includes a cross-cutting device 35, which is located downstream of the transverse sealing device 34 and the conveying device 32. During each intermittent conveying of the web 1, the cross-cutting device 35 cuts the main body 11, main body 12, and corner brace 13 transversely in the width direction of the main body 11 and main body 12. A bag 10 is produced during each cross-cutting. The cross-cutting position is the position of the transverse sealing part 15. The cross-cutting device 35 uses, for example, a cutter or a support platform to cut the bag's constituent components 11, 12, and 13 transversely.

[0063] Figure 3 express Figure 1A The bag 10 has corner supports 13 that function as bottom corner supports that give the bag 10 its self-standing ability. Additionally, the sealing portion 14 reinforces the self-standing ability of the bag 10. Furthermore, the sealing portion 14 has a V-shaped form before the cross-cutting process. The sealing portion 14 is divided into two parts during the cross-cutting. As a result, the sealing portion 14 becomes an inclined sealing portion located on both sides of the bag 10 and extending in the longitudinal and transverse directions of the bag 10. Edges 101 and 102 form the opening edges of the bag 10.

[0064] The heat sealing device 4 will be described below. Figure 4 As shown, the heat sealing device 4 includes a set of beams 40 arranged at intervals along a first horizontal direction X. In this embodiment, the first horizontal direction X is the length direction of the web-shaped main body 11 and main body 12, and coincides with the conveying direction X1. The beams 40 are respectively as shown in the diagram. Figure 4 As shown, the main body portions 11 and 12 extend along the entire width of the conveying path in the second horizontal direction Y, and as... Figure 5 As shown, it extends in the vertical direction Z to the sides of the main body 11 and main body 12. The second horizontal direction Y is perpendicular to the first horizontal direction X, and in the embodiment, it is consistent with the width direction of the main body 11 and main body 12.

[0065] The heat-sealing device 4 also includes a crossbeam 41, which is intermittently supported on a set of beams 40, either directly or via suitable components, and extends between the set of beams 40 in a first horizontal direction X. The crossbeam 41 is fixed at both ends to the horizontal extensions of the beams 40. The fixed position can be changed, allowing adjustment of the crossbeam 41 relative to the beams 40 in a second horizontal direction Y. The crossbeam 41 is located above the main body sections 11 and 12 on the transport path.

[0066] like Figure 5 As shown, the heat sealing device 4 also includes a slider 42, which is disposed on the crossbeam 41 in a manner that allows it to move vertically relative to the crossbeam 41. The slider 42 is located on the lower side of the crossbeam 41.

[0067] The heat sealing device 4 also includes a first heat sealing member 43 and a second heat sealing member 44. The first heat sealing member 43 is mounted on the slider 42 with the slider 42 facing the main body 11 and the main body 12, and moves together with the slider 42 in the vertical direction Z.

[0068] In one embodiment, the first heat-sealing component 43 includes a base 45 mounted on the sliding member 42 and a sealing plate 46 detachably mounted on the base 45.

[0069] like Figure 7 As shown, the sealing plate 46 includes a protrusion 460. The protrusion 460 is integrally formed with, for example, a plate portion of the sealing plate 46 and protrudes from that plate portion. The protrusion 460 has a flat surface 461 facing the second heat-sealing member 44 when the sealing plate 46 is mounted on the base 45. This surface 461 is the surface that is pressed onto the bag's constituent components 11, 12, and 13 during heat sealing, as described later. Furthermore, the surface 461 has a shape corresponding to the formed sealing portion 14. Therefore, in this embodiment, the surface 461 has a V-shaped shape.

[0070] The first heat-sealing member 43 is configured such that the sealing plate 46 can be mounted on the base 45 at multiple different positions relative to the second horizontal direction Y. This allows the position of the sealing plate 46 relative to the base 45 to be changed in the second horizontal direction Y. This can be achieved using known elements such as elongated holes 462 formed in the sealing plate 46 and bolts.

[0071] The second heat-sealing member 44 is arranged facing the main body portion 11 and the main body portion 12, and faces the first heat-sealing member 43 in the vertical direction Z. In this embodiment, the first heat-sealing member 43 is located above the main body portion 11 and the main body portion 12, and the second heat-sealing member 44 is located below the main body portion 11 and the main body portion 12. The surface of the second heat-sealing member 44 facing the first heat-sealing member 43 (sealing plate 46) can be a flat surface with the same shape as the surface 461 of the protrusion 460, or a flat surface that is sufficiently larger than the surface 461. The heat-sealing device 4 is configured to fix the second heat-sealing member 44 at a position consistent with the position of the first heat-sealing member 43.

[0072] like Figure 5 , Figure 6A As shown, the heat sealing device 4 includes at least two main force-applying components 47 (two in this embodiment) located between the crossbeam 41 and the sliding member 42. Figure 6A This is a YZ cross-sectional view of the location of the main force-applying member 47 (the illustration of the second heat-sealing member is omitted). In the embodiment, the main force-applying member 47 is a spring, oriented with its extension / retraction direction (force-applying direction) in the vertical Z direction.

[0073] In the embodiment in which the main biasing member 47 is a spring, a pressure bolt 48 is inserted coaxially through the main spring 47 and into the slider 42. The main spring 47 is positioned between a flange 480 of the pressure bolt 48 and the slider 42. The pressure bolt 48 penetrates the cross beam 41 and is positionally adjustable in the vertical direction Z with respect to the cross beam 41 by a thread on the outer periphery thereof. In addition, a nut 49 of a double nut structure is fitted externally to the pressure bolt 48. The pressure bolt 48 is fixed with respect to the cross beam 41 by the double nut structure. The pressure bolt 48 is freely slidable in the vertical direction Z with respect to the slider 42. The maximum distance between the cross beam 41 and the slider 42 is fixed by an adjustment bolt 53 (described later), and the compression state of the main spring 47 can be adjusted by positionally adjusting the pressure bolt 48 in the vertical direction Z with respect to the cross beam 41.

[0074] As shown in Figure 5 , Figure 6B , the heat-sealing device 4 has at least one secondary biasing member 50 positioned between the cross beam 41 and the slider 42. In the embodiment, two secondary biasing members 50 are provided. Figure 6B is a YZ cross-sectional view at the position of the secondary biasing member 50 (the second heat-sealing member is not shown).

[0075] In the embodiment in which the secondary biasing member 50 is a spring, a pressure bolt 51 is inserted coaxially through the secondary spring 50 and into the slider 42. The secondary spring 50 is positioned between a flange 510 of the pressure bolt 51 and the slider 42. The pressure bolt 51 penetrates the cross beam 41 and is positionally adjustable in the vertical direction Z with respect to the cross beam 41 by a thread on the outer periphery thereof. In addition, a nut 52 of a double nut structure is screwed to the pressure bolt 51. The pressure bolt 51 is fixed with respect to the cross beam 41 by the double nut structure. The pressure bolt 51 is freely slidable in the vertical direction Z with respect to the slider 42. The maximum distance between the cross beam 41 and the slider 42 is fixed by the adjustment bolt 53 (described later), and the compression state of the secondary spring 50 can be adjusted by positionally adjusting the pressure bolt 51 in the vertical direction Z with respect to the cross beam 41.

[0076] The main biasing members 47 are arranged in a straight line in the first horizontal direction X. The arrangement line L1 is shown in Figure 4 (refer to the position of the corresponding pressure bolt 48). The secondary biasing members 50 are arranged offset from the main biasing members 47 in the second horizontal direction Y (refer to the position of the corresponding pressure bolt 51). That is, the arrangement line L2 of the secondary biasing members 50 extending in the first horizontal direction X is offset from the arrangement line L1 of the main biasing members 47 in the second horizontal direction Y by a prescribed distance d1.

[0077] The two secondary biasing members 50 of the embodiment are arranged symmetrically with respect to a second horizontal direction center line C (refer to the arrangement line L2 of the secondary biasing members 50) on which the main biasing members 47 are arranged. Figure 4) are symmetrically arranged.

[0078] As shown in Figure 5 , Figure 8 , two adjustment bolts 53 are provided. Figure 8 is a YZ sectional view at the position of the adjustment bolt 53 (the second heat-sealing member is omitted). The adjustment bolt 53 is fixed to the slide 42. The adjustment bolt 53 is inserted through the cross beam 41 and is slidable in the vertical direction Z with respect to the cross beam 41. A nut 54 is screwed to the adjustment bolt 53. By the nut 54, the maximum interval between the cross beam 41 and the slide 42 can be adjusted, and thus the movable range of the slide 42 with respect to the cross beam 41 can be adjusted. With respect to the nut 54, by further adding a nut, a double-nut structure is formed, and the position of the nut with respect to the adjustment bolt 53 can be made less likely to change.

[0079] In the embodiment, after the maximum interval is fixed, by adjusting the compression states of the springs 47 and 50 as the biasing members respectively using the structure, the biasing forces of the springs 47 and 50 against the first heat-sealing member 43 when the constituent assembly 11, the constituent assembly 12, and the constituent assembly 13 of the bag are clamped using the first heat-sealing member 43 and the second heat-sealing member 44 are adjusted as described later, and thus the sealing pressure can be adjusted. The heat-sealing device 4 is configured so that the sub-spring 50 can be adjusted to a state in which the sub-spring 50 does not bias the first heat-sealing member 43 toward the second heat-sealing member 44 when the constituent assembly 11, the constituent assembly 12, and the constituent assembly 13 of the bag are clamped using the first heat-sealing member 43 and the second heat-sealing member 44. That is, the biasing force of the sub-spring 50 against the first heat-sealing member 43 at the time of heat-sealing is adjusted to zero, or in other words, the use of the sub-spring 50 at the time of heat-sealing can be selected.

[0080] As shown in Figure 5 , the heat-sealing device 4 includes an up-and-down moving mechanism 55 for moving the beam 40 and the cross beam 41 in the vertical direction Z to bring the slide 42 and the first heat-sealing member 43 close to and away from the second heat-sealing member 44. By the movement in the vertical direction Z, the constituent assembly 11, the constituent assembly 12, and the constituent assembly 13 of the bag are clamped by the first heat-sealing member 43 (the sealing plate 46) and the second heat-sealing member 44. The up-and-down moving mechanism 55 is linked with the intermittent conveyance of the web 1 by the conveyance device 32 to move these members 40 to 43 in the vertical direction Z. Such an up-and-down moving mechanism 55 is well known as disclosed in Patent Document 1 and Patent Document 2.

[0081] As shown in Figure 6A and Figure 6BAs shown, the heat-sealing device 4 includes a heat pipe 56 as a heater for heating the first heat-sealing member 43. In the embodiment, the heat pipe 56 is assembled into the first heat-sealing member 43, more specifically, into the base 45 thereof. By the heat pipe 56 emitting heat under temperature control, the first heat-sealing member 43 is heated to a temperature suitable for heat-sealing.

[0082] The heat-sealing operation will be described below with reference to Figures 9-11 . The web 1 (i.e., the constituent members 11, 12, 13 of the bag) is intermittently conveyed by the conveyance device 32 between the first heat-sealing member 43 and the second heat-sealing member 44. When the web 1 is temporarily stopped in the intermittent conveyance, the up-and-down moving mechanism 55 lowers the beam 40 and the cross beam 41, and the slide 42 and the first heat-sealing member 43 approach the second heat-sealing member 44, whereby the constituent members 11, 12, 13 of the bag are sandwiched by the first heat-sealing member 43 (the sealing plate 46 thereof) and the second heat-sealing member 44. Figure 9 , Figure 10 ).

[0083] The up-and-down moving mechanism 55 further lowers the beam 40 and the cross beam 41. At this time, the slide 42 and the first heat-sealing member 43 stop from being lowered any further. Thus, the cross beam 41 and the pressure bolt 48 move downward relative to the slide 42 and the first heat-sealing member 43. Figure 10 , Figure 11 ). As a result, the spring as the main biasing member 47 is compressed between the flange 480 and the slide 42 by the flange 480, and exerts a force via the slide 42 and the first heat-sealing member 43 to the constituent members 11, 12, 13 of the bag. When the spring as the secondary biasing member 50 is also used, its exerted force is applied in the same manner.

[0084] Thus, the surface 461 of the convex portion 460 ( Figure 7 ) heated by the heat pipe 56 is pressed against the constituent members 11, 12, 13 of the bag, and thus the constituent members 11, 12, 13 of the bag are heat-sealed thereby to form the sealing portion 14 having the same shape as the surface 461. In the embodiment, the body portions 11, 12 and the gusset portion 13 are sandwiched by the first heat-sealing member 43 (the sealing plate 46) and the second heat-sealing member 44, and heat-sealed to form the inclined sealing portion 14 in a V-shape.

[0085] Then, the up-and-down moving mechanism 55 returns the beam 40 and the cross beam 41 to the initial position ( Figure 9 ), and the slide 42 and the first heat-sealing member 43 are separated from the web 1 and the second heat-sealing member 44. Thereafter, the conveyance of the web 1 is resumed. The above is repeated to form the sealing portion 14 at each time of the intermittent conveyance.

[0086] To ensure proper sealing of the sealing portion 14, the core of the surface of the first heat-sealing member 43 that presses onto the components 11, 12, and 13 of the bag—that is, the portion of surface 461 that is actually pressed onto the components 11, 12, and 13 of the bag (hereinafter referred to as the effective sealing surface)—should coincide with the line of action (extending in the vertical Z direction) of the resultant force of the force applied by the force-applying member used for heat sealing. Thus, the applied force is evenly applied to the components 11, 12, and 13 of the bag via the effective sealing surface.

[0087] like Figure 12 As shown, in this embodiment, when manufacturing a bag 10 with the maximum folding amount of the gusseted portion 13 (the distance between the edges 103 and 104 of the main body 11 and 12 and the folded inner edge 100 of the gusseted portion 13) designed for the bag-making machine, the entire surface 461 of the protrusion 460 becomes the effective sealing surface and is pressed against the main body 11, main body 12, and gusseted portion 13. The operator adjusts the position of the sealing plate 46 using the elongated hole 462, etc., so that the intersection of the core G of the entire surface 461 with the configuration line L1 and the second horizontal direction center line C is flush in the vertical direction Z, and then the sealing plate 46 is positioned on the base 45. Only the main force-applying member 47 is used, and the secondary force-applying member 50 is not used. That is, the secondary force-applying member 50 is adjusted by the pressure bolt 51 so that no force is applied to the first heat-sealing member 43 during heat sealing. The line of action Lf of the resultant force of the applied force from only the main force-applying component 47 lies at the intersection of the configuration line L1 and the center line C of the second horizontal direction. Therefore, the core G is aligned with the line of action Lf.

[0088] Since the core G aligns with the line of action Lf, the total applied force is evenly transmitted to the entire surface 461, which serves as the effective sealing surface, and applied to the main body 11, main body 12, and corner brace 13. As a result, a good inclined sealing portion 14 can be formed.

[0089] In the case where the folding amount of the corner brace 13 is less than the maximum value of the bag 10 in the design, such as Figure 13 As shown, only Figure 13 The obliquely lined portion in surface 461 becomes the effective sealing surface. Its core G' deviates from the configuration line L1, that is, from the line of action Lf of the main force-applying member 47, towards the second horizontal direction Y. This deviation is indicated by the symbol d2. If the heat-sealing device 4 performs heat sealing in this state, the equal application of the applied force is impaired, which may lead to a decrease in the quality of the inclined seal 14. It is not possible to move the line of action Lf in the second horizontal direction Y by adjusting the applied force of the main force-applying member 47 alone.

[0090] Therefore, the auxiliary force-applying component 50 can be used together, such asFigure 13 As shown, the action line Lf' of the resultant force of the exertion forces of the main exertion member 47 and the sub exertion member 50 is made to coincide with the figure core G'. Also, for this, the resultant force of the necessary exertion force is set as F, the exertion force of the main exertion member is set as Fl, the exertion force of the sub exertion member is set as F2, and only the following two equations are satisfied. Therefore, the operator adjusts the exertion forces Fl, F2 using the pressure bolt 48, the pressure bolt 51 to satisfy the following two equations.

[0091] F = Fl + F2

[0092] Fl : F2 = (dl - d2) : d2

[0093] Thus, by using the sub exertion member 50, the action line Lf' can be adjusted in the second horizontal direction Y to coincide with the figure core G'. Thus, even when the amount of folding of the gusset portion 13 is changed, the sealing pressure can be applied uniformly. The quality of the inclined seal portion 14 can be prevented from deteriorating, and thus the problem of leakage of the contents from the inclined seal portion 14 can be prevented.

[0094] The heat sealing device 4 can adjust the action line of the resultant force of the exertion forces of the exertion members at least in the second horizontal direction Y by adjusting the exertion force of the sub exertion member 50 as exemplified above. Even in the case where the figure core of the effective sealing surface of the first heat sealing member 43 deviates from the arrangement line L due to a change in the design of the bag 10 or the like, the sealing pressure can be applied uniformly.

[0095] In the embodiment, as shown in Figure 14A and Figure 14B The end edge guide line 463 and the figure core guide line 464 can be formed in the sealing plate 46 in a prescribed interval, for example, in the form of an engraving or the like. The two guide lines 463, 464 are formed in a portion that the operator can easily see, and in the embodiment, as shown in Figure 14A , on the side surface of the plate portion of the sealing plate 46. Further, the two guide lines 463, 464 can also be formed on the surface on the side of the convex portion 460 of the plate portion.

[0096] For example, in the case where the bag 10 is manufactured such that the amount of folding of the gusset portion 13 is the largest in the design of the bag making machine, the sealing plate 46 is positioned with respect to the base 45 using a known element such as a long hole 462 so that the end edge 103, the end edge 104, and the end edge guide line are aligned with the "0" scale. The figure core G of the effective sealing surface at this time is aligned with the "0" scale of the figure core guide line 464. Also, only the action line Lf of the main exertion member 47 is aligned with the "0" scale of the figure core guide line 464.

[0097] As shown in Figure 14AAs shown, when the amount of folding of the gusset portion 13 is less than the maximum amount of folding of the bag 10 in the design of the bag making machine, the mark core G' of the effective sealing surface is aligned with the "2" scale of the mark core guide line 464 when the end edge 103, the end edge 104, and the end edge guide line 463 are aligned with the "2" scale. Therefore, as long as the pressure bolt 51 is operated so that the sub force applying member 50 also participates in heat sealing, the line of action is shifted from the position of the line of action Lf of the main force applying member 47 to the second horizontal direction Y (the width direction of the body portion 11, the body portion 12) by d2 to coincide with the mark core G'.

[0098] Thus, the two guide lines 463, 464 are configured so that the positional relationship of the scale of the end edge guide line 463 and the scale of the mark core guide line 464 corresponding thereto corresponds to the positional relationship of the end edge 103, the end edge 104, and the mark core G / G' of the effective sealing surface. This easily allows the operator to align the line of action Lf' with the mark core G' (see FIG. 6). Figure 13 ) with the mark core G'.

[0099] Further, the heat sealing device 4 capable of adjusting the line of action can also be used in a case where the mark core position of the effective sealing surface is changed due to a positional change of the sealing plate 46 with respect to the base 45, the sealing plate 46 is replaced with another sealing plate having a different shape of the convex portion, or the first heat sealing member 43 is replaced with another heat sealing member as a whole.

[0100] The web 1, and the constituent assembly 11, the constituent assembly 12, the constituent assembly 13 of the bag can include any one of a mono-material or a composite raw material if heat sealing and bag making are possible. For example, the constituent assembly 11, the constituent assembly 12, the constituent assembly 13 of the bag can each be a film of a multilayer structure including a base material layer and a sealant layer disclosed in Patent Literature 1 to Patent Literature 3.

[0101] The heat sealing device 4 of the embodiment heat seals the body portion 11, the body portion 12, and the gusset portion 13, but other constituent assemblies can also be heat sealed by the heat sealing device 4. The gusset portion 13 is not limited to a bottom gusset portion as in the embodiment, but can be a top gusset portion or a side gusset portion. The arrangement of the heat sealing device 4 in the bag making machine is also not limited to the example of Figure 1A and is appropriately determined according to the design of the bag. It can be easily understood by those skilled in the art that the heat sealing device 4 can be applied not only to the bag making method of the embodiment but also to various bag making methods.

[0102] The main force applying member 47 can also be a cylinder such as a pneumatic cylinder or an electric cylinder instead of a spring. The sub force applying member 50 can also be a cylinder such as a pneumatic cylinder or an electric cylinder instead of a spring. By adjusting the fluid pressure (pneumatic pressure) or stroke, the application force at the time of heat sealing can be adjusted. Since the application force can be calculated from the fluid pressure, the position of the line of action Lf' can be adjusted in a shorter time. In addition, the application force of the force applying member 47 / 50 can also be detected by a sensor.

[0103] In the case where an electric cylinder is used as the main force applying member 47 or the sub force applying member 50, for example, as shown in FIG. 8, in order to make the line of action Lf' of the resultant coincide with the figure core G', it is possible to control on the basis of the use of software to calculate the respective application forces of the electric cylinder 47, the electric cylinder 50. Figure 13

[0104] The pressure sensor can be sandwiched by the sealing plate 46 and the second heat sealing member 44. By using the measurement result of the pressure sensor, it is possible to confirm whether the line of action Lf' passes through the figure core G'.

[0105] The heat sealing device 4 or the bag making machine can further include a user interface such as an operation panel including a touch panel display. The heat sealing device 4 or the bag making machine can be configured to increase or decrease the application forces of the main force applying member 47 and the sub force applying member 50 in response to the operation of the user interface by an operator. This operation can be easily performed as long as it is an electric cylinder.

[0106] First, the application forces of the electric cylinder 47, the electric cylinder 50 can be controlled using values calculated using software. Then, it is possible to confirm whether the line of action Lf' actually passes through the figure core G' using the pressure sensor. Further, fine adjustment can be performed by the operation of the user interface.

[0107] Instead of the embodiment, three or more main force applying members 47 can be arranged on one straight line. One or three or more sub force applying members 50 can be arranged offset from the arrangement line LI to the second horizontal direction Y.

[0108] The surface 461 can have a shape suitable for the purpose, function, and use of the sealing portion in addition to the V-shaped shape.

[0109] Explanation of symbols

[0110] 10: bag

[0111] 11, 12: body portion (constituent member of bag)

[0112] 13: gusset portion (constituent member of bag)

[0113] 14: sealing portion / inclined sealing portion

[0114] ​4: Heat-sealing device

[0115] 40: Beam

[0116] 41: Cross beam

[0117] 42: Slider

[0118] 43: First heat-sealing member

[0119] 44: Second heat-sealing member

[0120] 45: Base

[0121] 46: Sealing plate

[0122] 460: Protrusion

[0123] 461: Surface of protrusion

[0124] 47: Main force-applying member

[0125] 50: Sub force-applying member

[0126] G / G': Figure core of sealing effective surface

[0127] L1: Arrangement line of main force-applying member

[0128] Lf: Line of action (using only main force-applying member)

[0129] Lf': Line of action (using main force-applying member and sub force-applying member)

Claims

1. A heat sealing apparatus for heat sealing constituent components of a bag, the heat sealing apparatus characterized by comprising: a plurality of beams arranged at intervals from each other in a first horizontal direction; a cross beam supported by the plurality of beams and extending in the first horizontal direction between the plurality of beams; a slide member configured to be movable in a vertical direction with respect to the cross beam; a first heat sealing member movable in the vertical direction with the slide member; a second heat sealing member facing the first heat sealing member in the vertical direction; a vertical movement mechanism for moving the plurality of beams and the cross beam in the vertical direction to bring the slide member and the first heat sealing member closer to and away from the second heat sealing member; at least two main force applying members located between the slide member and the cross beam for applying force to the slide member and the first heat sealing member toward the second heat sealing member when the constituent components of the bag are clamped by the first heat sealing member and the second heat sealing member; and a sub force applying member located between the slide member and the cross beam for applying force to the slide member and the first heat sealing member toward the second heat sealing member when the constituent components of the bag are clamped by the first heat sealing member and the second heat sealing member, the at least two main force applying members are arranged in a straight line in the first horizontal direction, the sub force applying member is arranged offset from the at least two main force applying members in a second horizontal direction at right angles to the first horizontal direction, the heat sealing apparatus is configured to adjust the force applied to the first heat sealing member by the sub force applying member.

2. The heat sealing apparatus according to claim 1, wherein the heat sealing apparatus is configured to adjust the sub force applying member to a state where no force is applied to the first heat sealing member when the constituent components of the bag are clamped by the first heat sealing member and the second heat sealing member.

3. The heat sealing apparatus according to claim 1, wherein the first heat sealing member includes: a base; and a sealing plate detachably attached to the base, the sealing plate includes a convex portion having a surface facing the second heat sealing member when the sealing plate is attached to the base, the heat sealing apparatus is configured to heat seal the constituent components of the bag clamped by the sealing plate and the second heat sealing member to form a sealing portion having the shape of the surface of the convex portion.

4. The heat sealing apparatus according to claim 3, wherein the first heat sealing member is configured such that the sealing plate is attachable to the base at different positions with respect to the second horizontal direction.

5. The heat sealing apparatus according to claim 1, wherein the sub force applying member is a spring or an air cylinder.

6. The heat sealing apparatus according to claim 1, wherein the at least two main force applying members are springs or air cylinders.

7. A bag making machine comprising the heat sealing apparatus according to any one of claims 1 to 6. ​

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