JP2020050374A - Seal blade for heat-seal roll - Google Patents

Abstract

To provide a seal blade for a heat-seal roll, which can prevent the occurrence of a sealing failure such as peeling of a joint part or the like, and does not require complex temperature control.SOLUTION: A plurality of seal blades are arranged at equal intervals in a circumferential direction and along a roll axial direction on the trunk circumferential surfaces of a pair of heat-seal rolls oppositely arranged to rotate in opposing directions, and configured to hold laminated packaging films between the heat-seal rolls, and seals the packaging films to each other by fusing under pressurization and heating. In the seal blade provided to at least one trunk circumferential surface of one of the heat-seal rolls, a groove having a depth smaller than the thickness of the laminated packaging films is provided at at least a position near the front side edge of the heat-seal rolls in a rotation direction on the front surface thereof so as to extend along the roll axial direction.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a sealing blade attached to a heat seal roll for heat-sealing a film for packaging, and in particular, to a liquid packaged object containing a powdery substance or a granular substance (hereinafter, simply referred to as " The present invention relates to a sealing blade suitably used for sealing a so-called contaminant-containing liquid packaged object in a liquid by heat-sealing the squeezed position while sequentially squeezing the liquid packaged object.

  Patent Literature 1 and Patent Literature 2 disclose filling and packaging machines for automatically filling a liquid bag into a packaging bag made of a packaging film such as a plastic film and performing heat sealing, particularly sealing in liquid. Automatic filling machines, such as those described, are well known.

  The automatic filling machine disclosed in these documents, for example, while continuously running a long packaging film composed of a laminated film including a base film layer and a sealant layer from above to below along the longitudinal direction. , Half-fold in the width direction so that the sealant layers face each other, heat-sealing the overlapping side edges of the film continuously by a vertical seal roll in the vertical direction to form a vertical seal portion and form the film. The surface of a pair of horizontal seal rolls extending along the width direction of the packaging film while supplying the liquid packaging material through the filling nozzle into the cylindrical packaging film through a filling nozzle, The heat sealing blade provided on the peripheral surface) forms a horizontal seal portion at predetermined intervals while squeezing the liquid packaged object, so that the package is manufactured continuously. And those are.

  In such a horizontal seal roll, when a pair of rolls rotate in opposite directions to each other, the opposing surfaces of the heat seal blades provided on the respective roll surfaces are first packaged in a portion on the front side in the rotational direction. Heat sealing is started by heating while holding the film for sandwiching, and furthermore, with the rotation of the pair of horizontal seal rolls, the pair of heat seal blades arranged oppositely rotate synchronously to fill. The wrapped object is squeezed upward, and the cooperative position of the opposing heat sealing blades reaches the rear side edge in the rotation direction, whereby the horizontal sealing to the packaging film is performed (generally, It is called "submersible seal."

JP-A-8-301237 JP 2006-248578 A

  In the automatic filling and packaging machine, a method called a so-called "submerged seal", that is, a horizontal seal while squeezing out a liquid packaged object sandwiched between films by a pair of horizontal seal roll seal blades by a roll. Since the method is a method of forming a portion, an article to be packaged is inevitably interposed in the horizontal seal portion, and a part thereof stays in the horizontal seal portion, remains, and is easily bitten. In particular, when powdery or granular impurities such as pepper and sesame are contained in the liquid packaged object, the foreign substances caught in the inside of the horizontal seal portion cause the fusion bonding of the horizontal seal portion. And there is a problem that peeling of the joint portion occurs, which results in liquid leakage.

  Furthermore, the contact time between the heat seal blade and the packaging film is shortened with the speeding up of the automatic filling and packaging machine, and the heat at the front end portion and the rear end portion in the rotation direction of the heat seal blade is particularly insufficient, There is a problem that heat sealing failure occurs in the packaging film portion that comes into contact with these portions. Conventionally, this problem has been dealt with by increasing the surface temperatures of the front end and the rear end of the heat seal blade in the rotation direction. However, in this method, the amount of heat removed from the sealing blade varies depending on the temperature of the material to be packed, presence or absence of impurities, the type of the packaging film, and the like. However, there is a problem that the temperature setting is difficult and complicated heating control is required.

  Accordingly, an object of the present invention is to form a heat-sealed portion while squeezing an object to be packaged by a pair of heat-sealing rolls (sealing in liquid), and in particular, to powdery or granular material (hereinafter simply referred to as “liquid”). ), The liquid packaged object can be effectively squeezed out to prevent biting, and even if there is an impurity that could not be squeezed out, An object of the present invention is to propose a seal blade for a heat seal roll which can prevent occurrence of a sealing failure (liquid leakage) such as peeling of a joint portion and does not require complicated temperature control.

As a result of intensive studies to achieve the above object, the inventors have arrived at the present invention according to the gist configuration described below.
That is, the present invention relates to a plurality of heat seal rolls arranged opposite to each other that rotate in opposite directions to each other, and a plurality of the heat seal rolls are arranged at equal intervals in the circumferential direction and along the axial direction of the rolls. It is a seal blade for sandwiching the stacked packaging films between the heat seal rolls, applying pressure and heating, and fusing and sealing the packaging films together,
For the seal blade provided on at least one of the body peripheral surfaces of the heat seal roll, the surface thereof, at least at a position near the side edge on the front side in the rotation direction of the heat seal roll, along the roll axis direction. A groove is provided which extends and is shallower in depth than the thickness of the packaging film overlapped.

In the present invention,
(1) the depth of the groove is 300 μm or less;
(2) The groove is provided on the surface of the seal blade in the vicinity of the front side edge in the rotation direction of the heat seal roll, as well as in the vicinity of the rear side edge and in the center. thing,
(3) the groove is provided only on the surface of the seal blade near the side edge on the front side in the rotation direction of the heat seal roll;
(4) The groove provided on the surface of the seal blade in the vicinity of the side edge on the front side in the rotation direction of the heat seal roll is provided between the outer edge thereof and the adjacent side edge on the front side of the seal blade. The distance is provided at a position of 0.5 to 3.0 mm,
(5) The groove provided at the center in the rotation direction of the heat seal roll is 0.5 to 0.5 mm from the center in the rotation direction to the front side edge and the rear side edge, respectively. 3.0mm away from each other,
(6) The sealing blade is used for sealing a foreign substance that seals a liquid packaged object including a powdery substance and a granular substance in liquid.
Is a more preferable solution.

  In the present invention, on the body peripheral surfaces of a pair of heat seal rolls rotating in opposite directions to each other, the seal blade surfaces provided at equal intervals in the circumferential direction, at least in a position near the front side edge in the rotational direction. A groove is provided along the axial direction of the heat seal roll, and the seal width (the length of the heat seal roll in the rotation direction) at a position near the front side edge in the rotation direction of the seal blade is provided by the groove. It is characterized in that the grooves are narrow and the grooves are shallower than the thickness of the overlapping packaging film.

  According to this, the pinching force (pressing force) at the side edge portion (hereinafter, referred to as an “edge portion”) on the front side in the rotation direction of the seal blade can be increased, so that the material filled by the edge portion can be increased. It is possible to effectively squeeze out the package, and thus to prevent the particulate matter to be packaged from being caught in the heat-sealed portion.

  Further, according to the present invention, it is not necessary to perform complicated temperature control as in the related art, and only by forming a groove on the surface of a wide seal blade, it is possible to sufficiently increase the pressing force of the edge portion, As a result, the strength of the heat seal at the edge of the heat seal portion on the side of the space to be filled with the packaged material (hereinafter, also referred to as the "seal edge") is increased, and the occurrence of poor sealing (liquid leakage) is suppressed, and a stable seal is performed. be able to.

  Further, in the present invention, by setting the depth of the grooves to be shallower than the thickness of the overlapping packaging film, particularly 300 μm or less, even in the grooves, the stacked packaging films are sandwiched and pressed. And by heating to complete fusion bonding with high strength.

  Further, according to the present invention, even in the case where powder or granular material (impurities) is contained in the liquid packaged object, the impurities can be squeezed out at the edge of the seal blade, Even if there is an impurity that could not be squeezed out, the impurity is finely pulverized by the high pressing force at the edge portion, and the resin of the packaging film melted into the pulverized impurity penetrates. Since it is tightly sealed in the heat-sealed portion, the joining of the heat-sealed portion is not hindered, and a sealing failure (liquid leakage) due to peeling or the like does not occur.

  According to the present invention, the groove is further provided in the vicinity of the side edge on the rear side in the roll rotation direction and / or at the center of the seal blade surface, so that only the position near the front side edge in the rotation direction is provided. In addition, the seal width (the length in the rotation direction of the heat seal roll) in the vicinity of the side edge and the central portion on the rear side becomes narrower, the clamping force (the pressing force) increases, and the seal strength of the entire heat seal portion is increased. Can be. Therefore, even if the foreign material is caught in the heat seal portion, the foreign material is finely crushed, etc., and is tightly sealed in the heat seal portion in a state where the molten resin of the packaging film has penetrated (impregnated). Therefore, for example, even if a packaging bag continuously manufactured by an automatic filling machine or the like is cut at the center position in the traveling direction of the packaging film in the heat sealing portion and separated into one bag or a plurality of bags, contamination may occur. There is no liquid leakage or the like caused by the object, and no foreign matter protrudes from the cutting position.

  Further, according to the present invention, the groove provided at a position near the front side edge in the rotation direction of the seal blade surface has a distance between the outer edge portion and the adjacent front side edge of 0.5. The width of the seal blade portion formed at the edge portion of the seal blade surface in the roll rotation direction is set to a narrow width of 0.5 to 3.0 mm. By increasing the holding force (pressing force) against the packaging film, it is possible to effectively perform the squeezing of the packaged objects and foreign substances to be filled, and the pulverization of the foreign substances, and the heat sealing portion to be formed. By sufficiently increasing the heat sealing strength of the seal edge, it is possible to effectively suppress the occurrence of poor sealing such as liquid leakage.

  Further, the groove provided at the center portion in the rotation direction of the seal blade is separated from the center position of the seal blade by 0.5 to 3.0 mm on the front side edge side and the rear side edge side of the seal roll, respectively. If it is provided in the position, the seal blade portion at the center of the seal blade formed between these two grooves can be narrowed, and the clamping force (pressing force) at the center of the seal blade can be increased. it can.

It is the schematic which shows an example of the vertical type filling and packaging machine provided with the sealing blade for heat seal rolls of this invention. FIG. 2 is an enlarged side view of a pair of first horizontal seal rolls provided in the vertical filling machine of FIG. 1. It is a partial perspective view of the seal blade for heat seal rolls of the present invention. It is a side view explaining the effect of the seal blade for heat seal rolls of the present invention. It is a side view which shows one Embodiment of the sealing blade for heat seal rolls of this invention. It is a side view which shows another embodiment of the sealing blade for heat seal rolls of this invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
The seal blade for the heat seal roll of the present invention can be used as a seal blade of a heat seal roll provided in various filling and packaging machines such as a vertical filling and packaging machine and a horizontal filling and packaging machine, a multi-row filling and packaging machine, Here, a case in which the vertical filling and packaging machine 1 shown in FIG. 1 is provided as a seal blade for a horizontal seal roll will be described as a representative example.

  The filling and packaging machine 1 guides one long packaging film F, which is continuously fed out from the film roll R and travels, from the upper side to the lower side while traveling continuously by the guide rod 2 during the traveling. The packaging film F is folded back in the width direction so that the sealant layers thereof face each other. In the figure, both side ends located at the left end of the packaging film F are overlapped with each other. These are continuously pressed and heated in the longitudinal direction (longitudinal direction) of the packaging film F by a pair of vertical sealing rolls 3 to form a vertical sealing portion 4, thereby forming the packaging film F into a cylindrical shape. Is what you do.

  The packaged material M supplied from a tank (not shown) through a pump and a supply path (not shown) is formed into a tubular shape by a filling nozzle 5 penetrating between the pair of vertical seal rolls from above to below. The inside of the film F ′ is continuously or intermittently filled by a predetermined amount. Thereafter, the packing film F ′ formed into a cylindrical shape after filling is heated and pressed over the entire width by a pair of first horizontal seal rolls 6a and 6b at a predetermined interval in the longitudinal direction and welded to each other. As a result, the horizontal seal portion 7 is formed intermittently. Thereafter, the horizontal seal portion 7 is pressed again by the second horizontal seal roll 8 to secure the seal, whereby a large number of packages W are continuously produced in a state where the packages W are connected in the longitudinal direction of the packaging film F. Bagged. The package W is cut into one bag or a plurality of bags by cutting the center position of the horizontal seal portion 7 by a cutting mechanism 12 provided on the downstream side of the second horizontal seal roll 8 as shown in the figure. Is also good.

  Here, as shown in an enlarged side view in FIG. 2, the pair of first horizontal seal rolls 6a and 6b are arranged to face each other in parallel with each other, and are configured to be rotationally driven in directions opposite to each other. Each of the first horizontal seal rolls 6a and 6b has a built-in heater and a seal blade 9 extending in the axial direction at equal intervals in the circumferential direction. Although four seal blades 9 are provided on each of the first horizontal seal rolls 6a and 6b in the figure, the number of the seal blades 9 is appropriately changed according to packaging conditions such as a seal pitch and a filling speed. be able to.

  The two first horizontal seal rolls 6a and 6b are driven to rotate in synchronization with each other, and based on this, the opposing seal blades 9 come into contact with each other and run between the first horizontal seal rolls 6a and 6b. While sandwiching the packaging film F ', the position is heated and pressurized, and the sealant layers located on the inner surface side of the packaging film F' are fusion-bonded to each other, whereby the horizontal seal portion 7 is formed.

  In FIG. 2, a case is described in which, as an embodiment, grooves 10a and 10b, which will be described later, are provided for four seal blades 9 provided on the respective peripheral surfaces of the pair of first horizontal seal rolls 6a and 6b. However, in the present invention, the grooves 10a and 10b may be provided only on one of the seal blades 9 of the pair of first horizontal seal rolls 6a and 6b. In this case, the same operation and effect can be expected. it can.

FIG. 3 is a partially enlarged perspective view of the first horizontal seal roll 6a.
The seal blade 9 of the embodiment shown in the figure extends on the peripheral surface of the first horizontal seal roll 6a along the axial direction thereof. On the surface of the seal blade 9, concave grooves 10a, 10b are provided at positions near both side edges 9a, 9b so as to extend in the axial direction of the horizontal seal roll 6a, and are formed by the grooves 10a, 10b. The surface of the seal blade 9 is divided into three strip-shaped seal blade portions 11a, 11b, 11c. In the embodiment shown in the drawings, two grooves 10a and 10b are provided on the surface of the seal blade 9, but in the present invention, at least the vicinity of the front side edge in the rotation direction of the horizontal seal roll 6a. The groove 10a may be provided at the position, and a plurality of grooves may be provided between the groove 10a and the groove 10b to further divide the surface of the seal blade 9 into a plurality of seal blade portions.

  When the tubular packaging film F ′ is sandwiched and heat-sealed by the first horizontal sealing roll 6a shown in FIG. 3, first, as shown in FIG. 9 is sandwiched between seal blade portions 11a located opposite to the side edges (edge portions) on the front side in the rotation direction of the horizontal seal rolls 6a and 6b. Thus, the liquid packaging material filled in the packaging film F 'is squeezed out with the rotation of the horizontal sealing rolls 6a and 6b, and the packaging film F' at the squeezed position is formed by the sealing blade portion 11a. Fusion bonding is performed by heating and pressing.

  At this time, since the sealing blade portion 11a is formed narrowly in the rotational direction via the groove 10a, the clamping force (pressing force) is higher than that of a wide sealing blade having no groove. In addition, it is possible to effectively squeeze the liquid packaged object, and to fuse and bond the packaging films F ′ to each other under the high pressure, so that the horizontal sealing portion 7 is located on the downstream side in the running direction of the packaging film F ′. The sealing strength of the sealing edge can be increased.

  As shown in FIG. 4B, the liquid packaged material discharged by the squeezing by the seal blade portion 11a is rotated by the pair of horizontal seal rolls 6a and 6b, and the center of the seal blade 9 in the roll rotation direction. After being squeezed upward through the seal blade portion 11b located opposite to the portion, as shown in FIG. 4 (c), the side edges of the horizontal seal rolls 6a, 6b on the rear side in the rotation direction ( Edge portions) are squeezed out by a high pressing force between the narrow sealing blade portions 11c located opposite to each other. Since the seal blade portion 11c is formed narrowly in the roll rotation direction via the groove 10b in the same manner as the seal blade portion 11a, the sealing blade portion 11c has a high clamping force (pressing force), and The sealing strength of the sealing edge on the upstream side in the traveling direction can be increased.

  Further, according to the sealing blade 9, even if the liquid packaged object contains granular impurities such as sesame and pepper, the impurities are removed by the narrow sealing blade of the pair of sealing blades 9. The parts 11a can be pushed out by the high pressing force between the parts, and even if the foreign matter is bitten, the foreign matter is finely crushed by the seal blade part 11a, and between the crushed foreign matter, Since the melted sealant resin of the packaging film F ′ is infiltrated and impregnated and is tightly sealed in the horizontal seal portion 7, the joining of the horizontal seal portion 7 is not hindered by the impurities, and the liquid No seal failure such as leakage occurs.

  As shown in FIG. 5, the distance L between the edge of the groove 10a and the side edge 9a on the front side of the adjacent seal blade 9 (the length in the rotational direction of the seal blade portion 11a) is 0.5. It is provided so as to be 3.0 mm. Thereby, the band-shaped sealing blade portion 11a located at the edge portion of the sealing blade 9 can be formed to have a narrow width, the clamping force on the packaging film F is effectively increased, and the object to be packaged is effectively squeezed. be able to. Similarly, the groove 10b is formed such that the distance between the edge thereof and the rear side edge 9b of the adjacent seal blade 9 (the length in the rotational direction of the seal blade portion 11b) is 1.0 to 3.0 mm. In this case, the sealing blade portion 11a and the sealing blade portion 11b can increase the strength of the sealing edge portion, which is the boundary of the horizontal sealing portion 7 on the side of the space to be filled with the packaged object, and The occurrence of defects can be more effectively prevented.

  In a packaging bag for filling and packaging a liquid package, the sealing edge of the heat seal portion surrounding the packaging bag, which is adjacent to the filling space of the package, is formed in a belt shape with a length of at least 0.5 mm. If formed continuously, sufficient sealing strength required for a packaging bag can be provided. Further, when the length of the sealing edge exceeds 3.0 mm, the sealing strength is related to the length. In the present invention, the distance L is preferably in the range of 0.5 to 3.0 mm, more preferably 1.0 to 2.0 mm.

  Further, the maximum depth of the groove 10a and the groove 10b is not more than the total thickness of a plurality of packaging films F to be heat-sealed by the contact between the sealing blades 9, not more than 300 μm, preferably not less than 30 μm and not more than 200 μm. More preferably, the thickness is 40 μm or more and 160 μm or less. According to this, the overlapping packaging films F can be heated and pressurized by firmly sandwiching the overlapping grooves 10 a and 10 b from the front and the back in the groove portions 10 a and 10 b. , And the sealing strength of the heat sealing portion can be increased.

  FIG. 6 shows another embodiment of the seal blade 9 of the present invention. The seal blade 9 has grooves 10a, 10b extending in the axial direction of the horizontal seal rolls 6a, 6b at positions near both side edges 9a, 9b, and the center of the seal blade 9 in the roll rotation direction. Grooves 10c, 10d are provided at positions spaced apart from the position on both side edges 9a, 9b, respectively, and the surface of the seal blade 9 is divided into five strip-shaped seal blade portions 11a by the four grooves 10a, 10b, 10c, 10d. , 11b, 11c, 11d, and 11e.

  When the packaging film F ′ is sandwiched and heated and pressed by a pair of horizontal seal rolls 6 a and 6 b provided with the seal blade 9, similarly to the above-described embodiment, a narrow portion located at the edge of the seal blade 9 is formed. The filled liquid packaging material is squeezed out by the high pressing force of the width sealing blade portions 11a and 11c, and it is possible to prevent the packaging material and foreign substances from being caught in the horizontal sealing portion 7, and In addition, the sealing edge of the horizontal seal portion 7 on the side of the space to be filled with the article to be packaged can be fusion bonded with high sealing strength.

  Moreover, in the seal blade 9 of the present embodiment, the groove 10c and the groove 10d are further provided between the grooves 10a and 10b, so that the seal blade portion 11b at the center of the seal blade 9 in the roll rotation direction has a narrow width. I have to. When the packaging film F 'is sandwiched and heated and pressed by a pair of horizontal seal rolls 6a and 6b having the seal blades 9, respectively, the sealing strength of the central portion of the horizontal seal portion 7 is caused by the contact between the seal blade portions 11b. Can be increased. Further, even if the foreign matter is caught in the horizontal seal part 7, the foreign matter is finely pulverized by the high pinching force of the seal blade portion 11b, and the molten sealant resin permeates the packaging film F '. For example, even if the horizontal sealing portion 7 is cut by the cutting mechanism 12 of FIG. 1 at the center position in the running direction of the packaging film F ′, the horizontal sealing portion There is no possibility that the foreign matter caught in the part 7 jumps out, and no liquid leakage or the like occurs due to the foreign matter.

DESCRIPTION OF SYMBOLS 1 Filling and packaging machine 2 Guide rod 3 Vertical seal roll 4 Vertical seal part 5 Filling nozzle 6a, 6b First horizontal seal roll 7 Horizontal sea part 8 Second horizontal seal roll 9 Seal blades 9a, 9b Side edges 10a, 10b, 10c, 10d Grooves 11a, 11b, 11c, 11d, 11e Seal blade 12 Cutting mechanism R Film roll F, F 'Packaging film

Claims (7)

A plurality of heat seal rolls arranged opposite to each other rotating in opposite directions, and a plurality of the heat seal rolls are arranged on the body circumferential surface at equal intervals in the circumferential direction and along the axial direction of the rolls. The packaging film is sandwiched between the heat-sealing rolls and pressurized, under heating, a sealing blade for fusing and sealing the packaging films together,
For the seal blade provided on at least one of the body peripheral surfaces of the heat seal roll, the surface thereof, at least at a position near the side edge on the front side in the rotation direction of the heat seal roll, along the roll axis direction. A sealing blade for a heat-sealing roll, wherein a groove is provided which extends and is shallower in depth than the thickness of the packaging film overlapped. The sealing blade for heat sealing according to claim 1, wherein the groove has a depth of 300 μm or less. The groove is provided at a position near the front side edge in the rotation direction of the heat seal roll, as well as at a position near the rear side edge and at the center of the seal blade surface, respectively. The seal blade for a heat seal roll according to claim 1 or 2, wherein The seal blade for a heat seal roll according to claim 1 or 2, wherein the groove is provided only on a surface of the seal blade near a side edge on a front side in a rotation direction of the heat seal roll. . The groove provided at a position near the side edge on the front side in the rotation direction of the heat seal roll on the surface of the seal blade, the distance between the outer edge thereof and the front side edge of the adjacent seal blade, The sealing blade for a heat seal roll according to any one of claims 1 to 4, wherein the sealing blade is provided at a position of 0.5 to 3.0 mm. The groove provided at the center in the rotation direction of the heat seal roll is 0.5 to 3.0 mm from the center in the rotation direction to the front side edge and the rear side edge, respectively. The seal blade for a heat seal roll according to claim 3, wherein the seal blade is at a remote position. The heat according to any one of claims 1 to 6, wherein the seal blade is used for a foreign substance seal that seals a liquid package including a powdery substance or a granular substance in liquid. Seal blade for seal roll.

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