JPH01188328A - Heat-sealing roll - Google Patents

Abstract

PURPOSE:To prevent extremely easily and reliably generation of defective sealing, by a method wherein positional control flanges are provided on at least two positions of rolls forming a pair in an axial direction and a heat-sealing blade is situated inward in a radial direction from the circumferential surface of the positional control flange. CONSTITUTION:Positional control flanges 34, 35 of the same diameter having a circular contour are provided respectively on at least two positions in an axial direction of each of rolls 32, 33 forming a pair, for example, both end parts. The one side roll 32 which is advancable, retreatable and displacable is approached to the other roll 33 whose position has been fixed and circumferential surfaces 34a, 35a of the respective positional control flanges abut against each other. Respective heat-sealing blades 36, 37 which are confronted with each other are positioned at intervals as are expected extremely easily and accurately as there are predetermined distances of radial direction among their circumferential surfaces and circumferential surfaces 34a, 35a of the flanges. Therefore, when a heat-sealing material is passed through between the heat- sealing blades 36, 37, a deposited resin layer of the heat-sealing material receives appropriate heating/pressurization always and heat sealing of the same is performed at sufficient strength.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a heat seal roll for mutually heat sealing resin layers of film materials, sheet materials, etc., each having at least - resin layers. This makes proper heat sealing extremely easy to achieve.

(Prior Art) Heat sealing of resin layers of film materials, sheet materials, etc. is currently performed for various purposes, and many types of heat seal rolls for this purpose have also been proposed.

FIG. 5 is a schematic side view illustrating a known heat seal roll that is applied to an automatic filling machine for liquid or viscous substances among various types of heat seal rolls; 2 rolls of film material
．． 3 each indicate a guide roll for the film material unwound from the take-up roll l-.

Here, the film material fed out from the winding roll 1,
For example, after passing through guide rolls 2 and 3, the laminated plastic film 4 is folded in half in the width direction by a film folding fitting 5, and then a vertical sealing roll 6 and a horizontal sealing roll, which also act as pull-out rolls for the laminated plastic film 4, are folded in half in the width direction. 7 in sequence.

Here, the vertical seal rolls 6 include a pair of rolls 6a that are arranged close to each other in parallel and rotate in opposite directions, a heater built into the rolls 6a, and a heater that rotates in the circumferential direction of the rolls 6a. Heat seal blade 6b provided in an extended manner
The vertical sealing rolls 6 function to heat-seal the free ends in the width direction of the laminated plastic film 4 passing therebetween in the vertical direction, as shown by diagonal lines in the figure.

Further, the horizontal seal roll 7 is arranged in the same manner as the roll 6a, and includes a pair of rolls 7a that are rotationally driven, a heater built into each roll 7a, and a heater extending in the length direction of the roll 7a. Heat seal blade 7b having an arc shape in the circumferential direction
The laminated plastic material 4 is heat-sealed in the transverse direction by this transverse sealing roll 7 at predetermined intervals in the longitudinal direction, also as indicated by diagonal lines in the figure.

In this way, the plastic film 4 that is sequentially heat-sealed in the vertical and horizontal directions is filled with a liquid or viscous substance by the nozzle 8, which injects the liquid or viscous substance into the inside of the plastic film 4 after the vertical sealing is completed. After filling and lateral sealing, the plastic film 4 is transferred to the lateral sealing portion 1 by a cuck roll 9 disposed below the lateral sealing roll 7.
In many cases, one bag at a time is cut from the middle part of the bag.

In such an automatic filling machine, heat sealing by the vertical sealing rolls 6 is performed between the flange-shaped heat sealing blades 6b of each pair of rolls 6a, as shown in the longitudinal cross-sectional view in FIG. 6(a). The free end of the plastic film 4 in the width direction is sandwiched between the plastic film 4.
By pressurizing and heating the horizontal seal roll 7
As shown in FIG. 6(b), heat sealing is performed by sandwiching the plastic film 4 between both heat-sealing blades 7b having an arc shape in the circumferential direction, pressurizing and heating it, and sealing the inner side of the plastic film 4. While expelling liquid or viscous substances present in the area upward or downward,
Each step is performed by melting the plastic film 4.

By the way, the clearance adjustment of the respective heat seal blades 6b, 7b of both heat seal rolls 6.7 is performed by moving one of each pair of rolls 6a, 7a to a predetermined position, as shown in a perspective view in FIG. The other roll 6a, ? a in each guide frame 11.12, with bearing members 13.14 supporting both ends thereof, movable toward and away from one of the rolls 6a, 7a. .1
The bearing members 13, 14 for the other rolls 6a, 7a are rotated manually by rotating the Asiast bolts 15, 16 which are screwed into the rollers 2 and abut against the respective bearing members 13, 14. Against or in accordance with the spring force of a spring interposed between the pair of rolls,
and one roll 5a.

This is done by displacing it with respect to 7a.

(Problem to be solved by the invention) However, the conventional heat seal roll 6.7
In this case, the clearance adjustment between the heat seal blades 6b and 7b is performed by manually operating the Asiast bolts 15 and 16, relying on the intuition of the operator, and in many cases, the clearance adjustment is made by manually operating the Asiast bolts 15 and 16. By manual operation, the thickness of the plastic film 4 can be reduced by several micrometers.
Since it was extremely difficult to correct the clearance by a few microns with sufficient precision, there was an extremely high possibility that sealing defects would occur in the vertical and horizontal seal portions of each heat seal roll 6.7. The problem was that it was expensive.

To explain this using the horizontal sealing part as an example, if the clearance between the pair of rolls 7a is too large and the pressing force against the plastic film 4 is insufficient, the longitudinal section enlarged approximately 600 times as shown in FIG. As shown in the diagram,
A liquid pool 19 remains in the seal portion 17 due to the inability to sufficiently squeeze out the liquid 18 as the packaged object, and a parting line 20 due to insufficient melting remains on the joint surface of the plastic film 4. will remain, resulting in a significant decrease in seal strength. On the other hand, if the clearance between the pair of rolls 7a is too small, as shown in the enlarged longitudinal cross-sectional view in FIG. The molten resin is pushed out from the end of the heat seal toward the rear in the direction of travel of the plastic film 4, and as a result, there is almost no resin in the sealing area that contributes to the adhesion of the plastic film 4, so the seal strength is reduced. In addition to this, the molten resin will be mixed into the packaged items.

The present invention advantageously solves the problems of the prior art, and in particular, eliminates the need for clearance adjustment that relies on the operator's intuition for each heat seal blade, thereby making it extremely easy to cause seal failures. To provide a heat seal roll that can reliably prevent the above problems.

(Means for Solving the Problems) In particular, the heat seal roll of the present invention is provided with circular position regulating flanges that are in contact with each other on the circumferential surface at at least two locations, for example, at both ends of each pair of rolls. At the same time, at least one of the heat-sealing blades of the pair of rolls extending in the length direction or the circumferential direction is set at a distance of, for example, tens of microns to several tens of microns from the circumferential surface of the position regulating flange.
It is located radially inward.

(Function) In this heat seal roll, by specifying the proximity position of the pair of rolls by the contact of each position regulating flange, the position between the heat sealing blades of each roll, especially the position regulating flange. Under the action of the heat-sealing blades, which are pre-positioned radially inward from the circumferential surface, the heat-sealing material, and thus its base material, as well as the desired thickness of the resin layer contributing to the thermal welding, are formed as desired. 6. Clearance can be ensured. As the heat-sealing material passes between the pair of rolls, the heat-sealing blade can always properly pressurize the heat-sealing material, thus preventing seal failures due to under- or over-pressurization. The occurrence can be almost completely prevented.

Here, anyone can easily bring the position regulating flanges of each roll into contact with each other, regardless of whether they are experienced or not, which advantageously reduces the number of man-hours required to adjust the clearance between both heat seal blades. will be done.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a diagram showing an embodiment of the present invention.

In the figure, 31 indicates a horizontal seal roll, and 32 and 33 indicate a pair of rolls constituting the horizontal seal roll 31, where the respective rolls 32 are arranged parallel to each other.
．． 33 is provided with a heater (not shown) inside thereof,
These are also rotationally driven in mutually opposite directions by driving means (not shown).

And here, each pair of rolls is 32°33
Position regulating flanges 34 of the same diameter and having a circular contour are provided at at least two locations in the axial direction, at both ends in the figure, of each of the
．． 35 are respectively provided, and these position regulating flanges 34
．． 35 mutually opposing circumferential surfaces 34a.

35a can be brought into contact with each other, and between their respective position regulating flanges 34, 35, a heat beam extending in the length direction and forming an arc in the circumferential direction is formed on the circumferential surface of each roll 32, 33. Seal blades 36, 37 are provided respectively, and each heat seal blade 36, 37, and thus its circumferential surface, are positioned at position regulating flanges 34, 35, as is clear from the cross-sectional view shown in FIG. 1(b). each peripheral surface 3 of
4a and 35a in the radial direction.

Here, the heat seal blade circumferential surface and the flange circumferential surface 3
The radial distance from 4a and 35a is determined based on the thickness of the base material of the heat-sealing material and the thickness of the resin layer that contributes to heat welding. , the distance is such that the welding resin layer has a thickness sufficient to provide the desired adhesive strength,
In most cases, the thickness is about 10-10 μm to several tens of μm.

According to the heat seal 31 configured in this way, for example, one roll 33 whose position is fixed is brought close to the other roll 32 which is movable forward and backward in the same manner as described in the conventional example. , by bringing the circumferential surfaces 34a and 35a of the position regulating flanges 34 and 35 into contact with each other, the opposing heat sealing blades 36 and 37 can close their circumferences, as shown in FIG. 1(b). Due to the existence of a certain radial distance between the surface and the flange circumferential surfaces 34a, 35a, the desired spacing can be positioned very simply and precisely 9
, such positioning will have excellent reproducibility.

Therefore, when heat-sealing material is passed between these heat-sealing blades 36 and 37 as shown by the imaginary lines in the figure, the welded resin layer of the heat-sealing material is always properly heated and pressurized. As a result, the sheet will be sealed with sufficient strength.

FIG. 2 is an enlarged vertical cross-sectional view showing the result of such heat sealing on a plastic film, which shows that 'liquid pools and parting lines that occur due to insufficient pressure and insufficient melting have been eliminated. It is clear that proper heat sealing can always be achieved by completely removing the heat seal and sufficiently preventing the welding resin from being squeezed due to overpressurization.

FIG. 3 is a longitudinal sectional view showing another embodiment of the present invention, in which only the heat sealing blade 37 of one roll 33 is positioned radially inward from the circumferential surface 35a of the position regulating flange 350. , the circumferential surface of the other heat sealing blade 36 is located within the same radius as the circumferential surface 34a of the position regulating flange 34.

In this example, the flange peripheral surface 35a and the heat seal blade 37
In other words, the heat-sealing blade 3 under the contact of both flange peripheral surfaces 34a and 35a.
By appropriately selecting the separation distance of 6.37, it is possible to always properly heat-seal the heat-sealing material with very simple rearrangement of the heat-sealing blade 36.37, as in the above-mentioned example. .

FIG. 4 is a cross-sectional view showing still another embodiment of the present invention, in which one roll 42 of a vertical seal roll 41 is made movable in and out of the other roll 43 whose position is fixed, and abutment of each roll 42, 43 at least two places in the axial direction on the circumferential surface;
Where position regulating flanges 44, 45 of the same diameter are provided, the example shown in FIG. The circumferential surface of the position regulating flange 44, 45 is located radially inward from the circumferential surface of the position regulating flange 44,45. Also,
In the example shown in FIG. 4(b), only the circumferential surface of one heat sealing blade 47 is located radially inward from the circumferential surface of the position regulating flange 45, and the other heat sealing blade 46 is located at the position regulating flange 45. It is located within the same radius as .

Also in these embodiments shown here, by locating at least one of the heat seal blades radially inward from the circumferential surface of the position regulating flange, the clearance adjustment of both heat seal blades 46 and 47 can be performed without position regulation. By bringing the circumferential surfaces of the flanges 44, 45 into contact with each other, heat sealing to the heat sealing material can be carried out very easily, and the circumferential surface of the position regulating flange and the circumferential surface of the heat sealing blade can be Based on the selected radial distance, it can always be correct.

Although this invention has been explained above based on the illustrated example, when only one heat seal blade is located radially inward from the circumferential surface of the position regulating flange, the heat seal blade opposite to the illustrated example may be , it is also possible to position it radially inward of the flange peripheral surface, and it is also possible to adjust the clearance of the heat seal blade by the action of a cylinder or other reciprocating drive means.

(Effects of the Invention) Thus, according to the present invention, the proximity limit position of each roll is specified by the contact of the position regulating flange of each roll, so that the position is located radially inward from the circumferential surface of the position regulating flange. Under the action of at least one of the heat-sealing blades, the clearance between both heat-sealing blades can be made as desired, which is extremely simple.
Moreover, by adjusting the clearance with excellent reproducibility, it is possible to almost completely eliminate the occurrence of seal failures.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing one embodiment of the present invention, Fig. 2 is an enlarged longitudinal sectional view showing the sealing result by the heat seal roll shown in Fig. 1, and Figs. 3 and 4 are respectively other embodiments of the invention. Figure 5 is a side view of a conventional heat seal roll applied to an automatic filling machine; Figure 6 is a vertical cross section of a conventional heat seal roll; Figure 7 is a heat seal roll. FIG. 8 is an enlarged vertical cross-sectional view showing a conventional heat-sealed portion. 31...Horizontal seal roll 32, 33, 42.43
...Rolls 34.35, 44.45...Position regulating flanges 34a, 35a...Surrounding surface 36.37.46.47...Heat seal portion...
・Vertical seal roll Fig. 2 Fig. 4 (a) 46.47 - Heat seal I Fig. 5 Fig. 6 Fig. 7 Fig. 8 (a) (b) Procedure amendment book 1988 3 June 7th Director General of the Patent Office Kunio Ogawa 1, Indication of the case 1988 Patent Application No. 10941 26 Name of the invention Heat seal roll 3 Person making the amendment Relationship to the case Patent applicant Taisei Houzai Co., Ltd. 4 , Figure 8 of the agent's drawings will be corrected as shown in the attached sheet. Figure 8 (corrected figure) (a) (b)

Claims (1)

[Claims] 1. A pair of rolls arranged close to each other in parallel and driven to rotate in opposite directions, a heater built into each roll, and the length direction of each pair of rollers. Alternatively, in a heat sealing roll having a heat sealing blade extending in the circumferential direction and having an arc shape in the circumferential direction, there is a heat sealing blade that is mutually connected to each other on the circumferential surface at at least two places in the axial direction of each pair of rolls. A heat seal roll is provided with a contacting position regulating flange, and at least one heat sealing blade of a pair of rolls is positioned radially inward from the circumferential surface of the position regulating flange.