JPH01238922A - Heat sealing roll - Google Patents

Abstract

PURPOSE:To remove an improper seal by providing circular position restricting flanges at two positions in contact with the peripheral surfaces of a pair roll bodies, disposing one heat seal cutter inside the peripheral surface and forming it of a tool steel. CONSTITUTION:Position restricting flanges 34, 35 having circular profiles of the same diameter are provided at two positions such as both ends of roll bodies 32, 33, opposite peripheral surfaces 34a, 35a can be in contact with each other, heat seal cutters 36, 37 extending longitudinally of the bodies 32, 33 and formed circumferentially in a circular arc state are provided, and disposed slightly radially inward from the peripheral surfaces 34a, 35a. The outer peripheral surfaces of the cutters 36, 37 are composed of surface parts 36b, 37b made of tool steel brazed thereto or the like. When a heat sealing material is passed between the cutters 36 and 37, a fusion-bonding resin layer of the material is suitably heated and pressurized to be heat sealed with 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 a film material, sheet material, etc. each having at least one resin layer. This makes it extremely easy to achieve proper heat sealing, and also improves the durability of the heat seal roll and, by extension, the heat seal blade.

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

FIG. 6 is a schematic side view illustrating a known heat seal roll that is applied to automatic filling machines for liquids or viscous substances among various types of heat seal rolls, and 1 in the figure shows the state where the slitter process has been completed. 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, the laminated plastic film 4 is folded in half in the width direction by a film folding fitting 5 after passing through a guide roll 2.3, and then a vertical sealing roll 6 and a horizontal sealing roll, which also act as rolls for pulling out the laminated plastic film 4, and a horizontal sealing roll. 7 in sequence.

Here, the vertical seal roll 6 includes a pair of roll main body portions 6a which are arranged close to each other in parallel and rotated in opposite directions, a heater built into the roll main body portion 6a, and a roll main body. The vertical sealing roll 6 is provided with a flange-shaped heat sealing blade 6b extending in the circumferential direction of the portion 6a, and this vertical sealing roll 6 prevents play in the width direction and ends of the laminated plastic film 4 passing between them. , which functions to heat seal in the longitudinal direction, as indicated by diagonal lines in the figure.

Further, the horizontal seal roll 7 has two roll body parts 6a.
A pair of roll body portions 7a are arranged in the same manner and are rotationally driven, a heater built into each roll body portion 7a, and a heater extending in the length direction of the roll body portion 7a in the circumferential direction. The laminated plastic film 4 is provided with an arc-shaped heat sealing blade 7b, and the laminated plastic film 4 is heat-sealed in the lateral direction by this lateral sealing roll 7 at a predetermined interval in the length direction, as also indicated by diagonal lines in the figure. will be administered.

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 completing such filling and lateral sealing, the plastic film 4 is fed from the middle of the lateral sealing portion 10 by a canter roll 9 disposed below the lateral sealing roll 7. One bag at a time is cut.

In such an automatic filling machine, heat sealing by the vertical sealing rolls 6 is performed using flanges provided integrally on each of the pair of roll main body portions 6a, as shown in the vertical cross-sectional view in FIG. 7(a). By sandwiching the free end of the plastic film 4 in the width direction between the shaped heat sealing blades 6b and pressurizing and heating the plastic film 4, the heat sealing by the horizontal sealing roll 7 can be performed using the seventh
As shown in Figure (b), both heat sealing blades 7b are integral with the roll body portion 7a and arc shaped in the circumferential direction.
A plastic film 4 is sandwiched between them, and it is pressurized and heated to expel the liquid or viscous substance present inside the plastic film 4 upward or downward, while melting the plastic film 4, and then, Each is performed by curing.

By the way, the clearance adjustment of the respective heat sealing blades 6b, 7b of both heat sealing rolls 6.7 is performed by adjusting one of the roll body portions 6a, 7a of each pair, as shown in a perspective view in FIG. Rotatably supported at a predetermined position, and the other roll body portion 6a, 7a
, in their respective guide frames 11.12, together with bearing members 13.14 supporting their ends, one roll body part 6a, ? The Asiast bolt 15.1 is screwed into each guide frame 11.12 and abuts on each bearing member 13.14 in a state where it can move forward and backward with respect to a.
6 by manual operation, the other roll body portion 6a, ? Bearing member 13.1 for a
4 is displaced relative to one of the roll body portions 6a, 7a against or in accordance with the spring force of a spring interposed between each pair of rolls.

(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 done by manually operating the Asiast bolts 15 and 16 based on the intuition of the operator, and in most cases the clearance is adjusted by several tens of microns. By manual operation, the plastic film 4 with a thickness of several μ
Since it was extremely difficult to adjust the clearance by a few microns with sufficient accuracy, there was a risk 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 extremely expensive.

To explain this using the horizontal seal portion as an example, the clearance between the pair of roll body portions 7a is too large.
If the pressure applied to the plastic film 4 is insufficient, the liquid 18 as the packaged object may be applied to the sealed portion 17, as shown in the vertical cross-sectional view enlarged approximately 600 times in FIG.
A liquid pool 19 remains due to the inability to sufficiently squeeze out the resin upward or downward, and a parting line 20 remains on the joint surface of the plastic film 4 due to insufficient melting of the resin layer. As a result, the seal strength will be significantly reduced.

On the other hand, if the clearance between the pair of roll body portions 7a is too small, as shown in the enlarged longitudinal cross-sectional view in FIG. 9(b), the pressure applied to the plastic film 4 is too high. , a large amount of molten resin,
By being pushed out from the end of the heat seal toward the rear in the direction of travel of the plastic film 4, almost no resin that contributes to adhesion of the plastic film 4 is present in the seal portion 17 (as a result, the seal strength is significantly reduced). At the same time, the molten resin will be mixed into the packaged item.

In addition, such conventional heat seal rolls 6.7,
In particular, those heat seal blades 6b.

7b are all made of structural carbon steel, mostly 555C, and since the surface hardness cannot be made very high, the heat sealing blades 6b and 7b wear out relatively quickly due to repeated heat sealing. This means that when the packaged item is wasabi or other natural food or contains natural food, some sand or other hard substances attached to or contained in the natural food may not be heat-sealed. This was especially serious when the blade was caught between the blades.

Therefore, in this prior art, in order to continue proper heat sealing, it is necessary to frequently perform troublesome rearrangement of the heat sealing blades 6b, 7b. When large irregularities occur due to encroachment of sand or other hard substances, it is virtually impossible to continue sufficiently proper heat sealing even with such clearance adjustment.

This invention advantageously solves the problem of the prior art, and eliminates the need for clearance adjustment of each heat seal blade that relies on the operator's intuition, thereby preventing seal failures and making it easier. In addition to reliably preventing damage, we have developed a heat seal roll that effectively prevents damage to the heat seal blade, allowing proper heat sealing to be continued for a long period of time without the need for adjusting the clearance of the heat seal blade. This is what we provide.

(Means for Solving the Problems) In particular, the heat seal roll of the present invention has circular position regulating flanges that are in contact with each other on the circumferential surface at at least two places, for example, at both ends, of each of the pair of roll body parts. , and at least one heat-sealing blade extending in the length direction or circumferential direction of each pair of roll main body portions is set radially inward from the circumferential surface of the position regulating flange, for example, from tens of microns to several tens of microns. and at least,
The surface portion of the heat seal blade extending in the length direction of the roll body is made of tool steel.

(Function) In this heat-sealing roll, by specifying the proximity position of the opposing roll body portions by contacting the respective position regulating flanges, the heat-sealing blades of the respective roll body portions, in particular, can be sealed. Under the action of the heat-sealing blade, which is pre-positioned radially inward from the circumferential surface of the position-regulating flange, the heat-sealing material, and therefore its base material, and the position depending on the thickness of the resin layer contributing to thermal welding are Since the desired clearance can be ensured, the heat-sealing blade can always properly pressurize the heat-sealing material as it passes between the pair of rolls. Therefore, it is possible to almost completely prevent the occurrence of seal failures due to insufficient or excessive pressurization.

Here, the position regulating flanges of each roll are brought into contact with each other by the action of screw means, cylinders, etc.
Since anyone can easily perform this process regardless of whether they are experienced or not, the number of man-hours required to adjust the clearance between the two heat-sealing blades is advantageously reduced.

Moreover, here, by forming at least the surface portion of the heat-sealing blade of the horizontal sealing roll with tool steel, for example, high-speed steel, the surface hardness of the heat-sealing blade can be significantly increased. Not only is normal wear and tear on the blade surface almost completely prevented, but even if sand or other hard substances get caught between the heat seal blades, scratches on the heat seal blade surfaces will not occur. This is sufficiently prevented, and therefore, proper heat sealing can be continued for a long period of time without the need for adjusting the clearance of the heat sealing blade.

Here, the tool steel on the surface of the heat-sealing blade can be attached to the main body of the heat-sealing blade by brazing or other methods.

In addition, here, the heat seal blade body portion of the heat seal roll, and sometimes the position regulating flange, are also constructed separately from the roll body portion, and when they are assembled afterwards, the The number of man-hours required to manufacture the seal roll can be effectively reduced, and this is especially noticeable when the heat seal blades of the horizontal seal roll are constructed separately. In addition, it is possible to sufficiently prevent a decrease in material yield by reducing the amount of material removed, and it is also possible to replace only the worn heat seal blade.

Note that each heat-seal blade can be attached to the roll main body by brazing, screwing, or other known methods. It is preferable to perform subsequent polishing, grinding, etc.

(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 roll body portions constituting the horizontal seal roll 31. Here, the roll body portions 32 and 33 are arranged parallel to each other. are provided with heaters (not shown) inside them, which are also driven to rotate in mutually opposite directions by driving means (not shown).

And here, each pair of roll body parts 3
2.33 in at least two axial locations, preferably at both ends in the figures, preferably in their roll body portions 32.
Position regulating flanges 34 and 35 are provided separately from the position regulating flanges 34 and 33 and have circular contours of the same diameter, and the opposing circumferential surfaces 34 of these position regulating flanges 34 and 35 are provided.
a, 35a can be brought into contact with each other, and
on each roll body portion 32.33, extending along their length between respective position-limiting flanges 34.35;
Each of these is provided with heat seal blades 36 and 37 each having an arc shape in the circumferential direction.

As is clear from the cross-sectional view of FIG. 1(b), the heat-sealing blades 36, 37, and thus their circumferential surfaces, are connected to the respective circumferential surfaces 34a of the position regulating flanges 34, 35.
, 35a, located somewhat radially inward.

Here, each heat sealing blade 36.37 has a heat sealing blade surface portion 36a, 37a projecting radially outwardly from the respective roll body portion 32.33 and a heat sealing blade surface portion 36a, 37a, which may be made of carbon steel, for example. body part 3
It consists of surface parts 36b and 37b made of tool steel fixed to the outer peripheral surfaces of 6a and 37a by brazing or other means.

These surface portions 36b, 37b can be made of carbon tool steel, high speed tool steel, or alloy tool steel having a thickness of about 2 mm, among others, 5KH4A or S of high speed tool steel. It is preferable to use a material of the order of /KH4B.

Such heat seal blades 36, 37 are pre-quenched,
For example, the surface portion 36b is vacuum hardened.

37b to the heat-sealed blade body portions 36a, 37a, and preferably thereafter the respective surface portions 36b, 37b are ground or polished.

In the example shown here, each heat seal blade body portion 36
Although the outer peripheral surfaces of a and 37a are also arcuate surfaces, they may also be flat surfaces.

When manufacturing the horizontal seal roll 31 as described above, it is possible to integrally mold the heat seal blade body parts 36a and 37a with the roll body parts 32 and 33, but it is also possible to mold each of them separately. In this case, each of the heat seal blades 36 and 37 is attached to the roll body portion 32.33 by attaching the heat seal blades 36 and 37 to the roll body portion 32.33 processed into a cylindrical shape at a predetermined interval in the circumferential direction. A plurality of grooves 32a and 33a are provided each extending in the axial direction, three grooves 32a and 33a are provided in the figure. Naru heat seal blade 36.37
are fitted into each groove 32a, 33a and fixed within each groove by brazing or other known methods,
In particular, the heat-sealing blades 36, 37 whose outer peripheral surfaces are not formed in an arcuate shape, and more preferably, the outer peripheral surfaces of all the heat-sealing blades 36, 37, are finished by polishing, grinding, or the like. In addition, when each position regulating flange 34.35 is configured separately from the roll body portion 32.33, the attachment of those flanges 34°35 to the roll body portion 32.33 is formed in an annular shape. This is done by screwing, keying, brazing, etc. the respective flange 34,35 to the end face of the roll body part 32,33, which also preferably has a finished finish. Add polishing, grinding, etc.

Here, the radial distance between the heat-sealing blade circumferential surface and the flange circumferential surfaces 34a and 35a is determined in relation to the base material thickness of the heat-sealing material and the resin layer thickness that contributes to thermal welding. The distance is set such that a sufficient pressure is applied to the welding resin layer and the thickness of the welding resin layer is sufficient to provide the desired adhesive strength. It should be about 10μ.

According to the horizontal seal roll 31 configured in this way,
For example, one roll body portion 33 whose position is fixed
Then, the other roll main body portion 32, which is movable forward and backward relative to it, is placed on the lateral side in the same way as described in the conventional example, and the peripheral surfaces 34a, 35 of the respective position regulating flanges 34, 35 are
By bringing the blades a into contact with each other, as shown in FIG.
are those peripheral surfaces and the flange peripheral surfaces 34a and 35a
Due to the existence of a predetermined radial distance between Become.

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.

Figure 2 is an enlarged vertical cross-sectional view showing the result of such heat sealing on plastic film, which shows that the liquid pools and parting lines that occur due to insufficient pressure and melting are completely removed. It is clear that it is possible to sufficiently prevent the welding resin from being over-squeezed due to excessive pressure, and to always achieve proper heat sealing.

Moreover, since each of the heat-sealing blades 36 and 37 has highly hard surface portions 36a and 37a made of tool steel, the wear resistance thereof is significantly improved. Even if sand or other hard substances get caught in between, there is little or no unevenness on the heat seal blade surface, so the heat seal blade 36, 37 can be properly adjusted without frequent rearrangement adjustment. Heat sealing can be continued for a long period of time.

In addition, as mentioned above, the heat seal blade body portion 36
a, 37a and/or position regulating flange 34°3
5 is configured separately from the roll body portions 32 and 33, the number of man-hours required for machining them can be significantly reduced, and at the same time, the material retention can be sufficiently improved.

FIG. 3 is a longitudinal cross-sectional view showing another embodiment of the present invention, which shows a horizontal seal roll manufactured in substantially the same manner as described in the previous example, with a heat sink attached to one roll main body portion 33. Only the sealing blade 37 is located radially inward from the circumferential surface 35a of the position regulating flange 35, and the circumferential surface of the other heat sealing blade 36 is positioned within the circumferential surface 35a of the position regulating flange 35.
It is located within the same radius as the circumferential surface 34a of.

In this example, the flange peripheral surface 35a and the heat seal blade 3
By appropriately selecting the radial distance from the circumferential surface of the heat seal blade 36, 37, in other words, the distance between the heat seal blades 36 and 37 when the two flange circumferential surfaces 34a and 35a are in contact with each other, as in the example described above, By extremely simple rearrangement of the heat sealing blades 36 and 37, proper heat sealing can always be applied to the heat sealing material. It can provide significant period continuity as well as manufacturing benefits.

FIG. 4 is a longitudinal sectional view showing still another embodiment of the present invention, in which each roll body portion 32, 33
The heat sealing blades 36, 37 attached to the roll body portions 32, 33 are thinned in the direction opposite to the rotational direction of the roll body portions 32, 33, and the outer surfaces of the respective piece-shaped heat sealing blade body portions 36a, 37a, The surface portions 36b and 37b made of tool steel are fixed to each other.

According to this example, the circumferential surface of the heat seal blade 36.37 is
Located radially inwardly of the circumferential surface of the position-limiting flange 34.35, as well as the respective heat-sealing blade 36.37, a surface portion 36b made of tool steel.

37b, it is possible to bring about the same effect as each of the above-mentioned embodiments, and it also makes heat sealing more appropriate based on the elastic deformation and heat dissipation effect of the thin portions of the heat sealing blades 36 and 37. be able to.

Furthermore, here, since the heat sealing blades 36, 37 and, by extension, their main body portions 36a, 37a have a more complicated shape than in the above-mentioned example, when cutting them from book material, This would require a significantly large number of man-hours, but the roll main body portions 32, 33 and the heat seal blade main body portions 36a, 37a are constructed separately.
By combining them afterwards, it is possible to realize a sufficient reduction in the number of work steps, and at the same time, it is also possible to greatly improve the material yield.

Note that in each of the embodiments described above, the roll body portion 32, 33 and the heat seal blade body portion 36b.

37b is configured separately, if any of the multiple heat seal blades suffers wear or other damage,
Proper heat sealing can be continued simply by replacing the heat seal blade.

FIG. 5 is a sectional view showing still another embodiment of the present invention, in which one roll main body portion 42 of a retaining seal roll 41 is made movable toward and away from the other roll main body portion 43 whose position is fixed. , where position regulating flanges 44,45 of the same diameter are provided in at least two locations in the axial direction of each pair of roll main body portions 42,43, which abut each other on the circumferential surface, as shown in FIG. In the example shown in (a), both heat-sealing blades 46 are annular.
Both the circumferential surfaces of the heat seal blades 46 and 47 are positioned radially inward from the circumferential surfaces of the position regulating flanges 44 and 45, and these heat seal blades 46 and 47 are connected to the heat seal blade main body portion 46a.

47a, and tool steel surface portions 46b and 47b' fixed to their outer peripheral surfaces. Further, in the example shown in FIG. 5(b), the surface portion 47b made of tool steel is
Only the circumferential surface of one heat sealing blade 47 having a surface portion 46b is located radially inward from the circumferential surface of the position regulating flange 45, and the other heat sealing blade 46 having a surface portion 46b also made of tool steel is positioned radially inwardly from the circumferential surface of the position regulating flange 45. It is located within the same radius as the restriction flange 44.

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 peat sealing material can be carried out very easily, and by bringing the circumferential surfaces of the position regulating flange and the circumferential surface of the heat sealing blade into contact with each other. Based on the selected radial distance, it can always be correct.

Moreover, here, each heat seal blade is 46°47
By providing the highly hard surface portions 46b, 47b made of tool steel, proper heat sealing can be maintained over a long period of time without the need for frequent clearance adjustments of the heat sealing blades 46,47.

Further, here, the annular heat-sealing blade body parts 46a, 47a are configured separately from the roll body parts 42, 43, and are assembled by known methods such as keying, screwing, brazing, etc. , as described in the previous embodiment, it is possible to significantly reduce the manufacturing man-hours and repair costs of the vertical seal roll 41,
Material yield can be sufficiently improved.

(Effect of the Invention) Thus, according to the present invention, the proximity limit position of the roll main body portion is specified by the contact of each position regulating flange, so that the roll main body portion is located radially inward from the circumferential surface of the position regulating flange. Under the action of at least one heat-sealing blade, the clearance between both heat-sealing blades can be adjusted to the desired level. The outbreak can be almost completely eliminated.

Furthermore, by forming at least the surface portion of the heat-sealing blade extending in the length direction of the roll main body with tool steel, the wear resistance of the heat-sealing blade is significantly increased, and the surface of the heat-sealing blade is It is possible to extremely effectively prevent the occurrence of unevenness, and to continue proper heat sealing for a long period of time without the need for frequent rearrangement of the heat sealing blade.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing one embodiment of the present invention, Fig. 2 is an enlarged vertical cross-sectional view showing the sealing result by the heat seal roll shown in Fig. 1, and Fig. 3.4.5 is a diagram showing another embodiment of the present invention. FIG. 6 is a side view of a conventional heat seal roll applied to an automatic filling machine; FIG. 7 is a vertical cross section of a conventional heat seal roll; FIG. 8 is a heat seal roll. FIG. 9 is a perspective view illustrating a seal roll clearance adjustment mechanism; and FIG. 9 is an enlarged vertical cross-sectional view showing a conventional heat seal portion. 31...Horizontal seal roll 32.33, 42.43...Roll body part 34.3
5, 44, 45...Position regulation flange 34a, 35a
...Surrounding surface 36.37, 46.47 ...Heat seal blade 36a
, 37a, 46a, 47a... Heat seal blade main body portion 36b, 37b, 46b, 47b...
Surface portion 41... Vertical seal roll Fig. 2 Fig. 3 Fig. 1 Fig. 4 Fig. 6 Fig. 7

Claims (1)

[Scope of Claims] 1. A pair of roll body parts arranged close to each other in parallel and driven to rotate in opposite directions, a heater built into each roll body part, and each pair of roll body parts. In a heat seal roll having a heat seal blade extending in the length direction or circumferential direction of a portion and forming an arc shape in the circumferential direction, the roll body portions of each of the paired roll body portions are spaced apart in the axial direction. At least two position regulating flanges are provided in contact with each other on the circumferential surface, and at least one heat sealing blade of each pair of roll body portions is positioned radially inward from the circumferential surface of the position regulating flange. ,at least,
A heat-sealing roll characterized in that a surface portion of a heat-sealing blade extending in the length direction of the roll body is formed of tool steel.