JPH06285953A - Molding apparatus for film and the like - Google Patents

Abstract

PURPOSE:To prevent the falling of a condensed liquid of a molten resin to an air blowoff port by allowing the molten resin to flow toward the rear edge of an upper plate member without accumulating the same on the upper plate member by forming the upper plate member of an air chamber so as to downwardly incline the same from the front edge to the rear edge thereof. CONSTITUTION:A resin to be extruded is emitted in a film form from a T-die 1 to be wound around a rotary cooling roll 3 to be cooled and solidified and the formed film is successively taken up by a takingup device while both ends thereof are trimmed. An air chamber 8 sprays air on the surface of the film 2 in the vicinity of the area where the film 2 comes into contact with the cooling roll 3 not only to bring the film 2 into close contact with the cooling roll 3 but also to cool the same. Since an upper plate member 11a is inclined from the front edge 15 to the rear edge 16 thereof, a condensed liquid is not accumulated on the upper plate member 11a and flows toward the rear edge 16 and does not fall to the air blowoff port 9 of the air chamber 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film or sheet forming apparatus, and more particularly to an air blowing section thereof.

[0002]

2. Description of the Related Art Conventionally, in a molding apparatus for molding a resin-based film or sheet, a molten raw material resin is extruded by an extruder and discharged from a T-die, and cooling water is circulated inside. It is wound around a roll, cooled and solidified, and then successively taken up by a take-up device and trimmed at both ends to complete molding. During this forming process, air is blown into the film in order to complete the winding when the material discharged from the T-die is wound around the cooling roll, and to cool the material in the vicinity of the winding portion and to improve the adhesion to the cooling roll. Alternatively, it is sprayed on the surface of the sheet (hereinafter referred to as film). This method is far more effective at an appropriate molding speed or lower as compared with the case of using other things such as static electricity.

A typical example of the conventional device will be described below with reference to FIG. FIG. 3 shows an example in which an air chamber is used as an air blowing device. In the figure, 1 is a T die which is mounted on the tip of an extruder (not shown) and discharges a molten resin in a film form, and 2 is a T die. 1 is a film discharged from 1, 3 is a cooling roll arranged near the discharge port of the T die for cooling and solidifying the discharged film 2,
The surface is kept at a low temperature by passing water or other heat medium inside, and is connected to a driving device (not shown) to rotate in the arrow direction. FIG. 3 shows an example using the air chamber 8, the upper plate 11 of which is parallel to the horizontal line passing through the center of the cooling roll 3, and the tip 12 is formed in a tapered shape for uniform air flow. ing. Reference numeral 9 is an outlet for blowing air from the air chamber 8, and 10 is a main pipe.

To form a film or the like with the film forming apparatus having the above-described structure, the resin melted and extruded by an extruder (not shown) is discharged from the T die 1 in the form of a film to rotate a cooling roll. 3 is wound around, cooled and solidified, and then sequentially taken up by a take-up device (not shown) and trimmed at both ends to be wound. The air chamber 8 blows air onto the surface of the film 2 or the like in the vicinity of a portion where the film 2 or the like contacts the cooling roll 3 to bring the film 2 or the like into close contact with the cooling roll 3 and to cool the film. The air blown from the air chamber 8 is supplied from a blower (not shown) to the main pipe 10 through the flow rate adjusting valve 7. The air is rectified from the air chamber 8 to a static pressure and blown onto the film 2 or the like to blow the film 2 or the like. Press on the cooling roll 3.

[0005]

The above-described conventional film forming apparatus for film or the like has the following problems to be solved.

That is, in the conventional apparatus, the molten resin immediately after being discharged from the T-die 1 has a high temperature, and the content of the resin evaporates, but it is cooled and condensed relatively quickly at the outside temperature. After this condensate collects in the upper plate 11 of the air chamber, it drops from the tip 12 to the air outlet 9 and is blown to and adheres to the surface of the film 2 by the air. There was a problem of damage.

An object of the present invention is to provide a molding apparatus for films and the like, in which such problems are solved.

[0008]

As a means for solving the above problems, the present invention is provided for cooling molten resin discharged from a T-die at a winding portion of a cooling roll and for bringing the molten resin into close contact with the cooling roll by wind pressure. A film forming device having an air blowing device having a ceiling as an upper plate, wherein the upper plate is inclined downward from a front edge to a rear edge thereof. Is to provide.

[0009]

Since the present invention is constructed as described above, it has the following actions.

That is, since the upper plate is inclined downward from the front edge to the rear edge, the condensed liquid of the molten resin that has evaporated and condensed immediately after being discharged from the T die and has descended on the upper plate is obtained. It cannot collect, flows in the direction of the trailing edge, and does not fall into the air outlet.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The first and second embodiments of the present invention will be described with reference to FIGS. The same members as those in the conventional example or the previous embodiment are designated by the same reference numerals, and the description thereof will be omitted unless necessary.

(First Embodiment) A first embodiment will be described with reference to FIG.

FIG. 1 is a side sectional view of this embodiment using an air chamber as an air blowing device. In the figure, reference numeral 1 is a molten resin which is attached to the tip of an extruder (not shown) and is discharged in the form of a film. A T-die, 2 is a film discharged from the T-die 1, 3 is a cooling roll arranged near the discharge port of the T-die for cooling and solidifying the discharged film 2, and water or other The surface is kept at a low temperature through the above heat medium, and it is connected to a driving device (not shown) to rotate in the direction of the arrow. 8 is an air chamber, and its upper plate 1
1a is formed to be inclined downward from the front edge 15 to the rear edge 16. That is, in FIG. 1, the straight line L1 is a horizontal line passing through the center of the cooling roll 3, the L2 is an extension line of the upper plate 11a, and the angles of the straight lines L1 and L2 are formed at θ. Further, the inside of the front edge 15 is tapered toward the end so that the air flow can be discharged uniformly. The lower plate 17 on the opposite side is formed in the same manner as the conventional one. Reference numeral 9 is a mouth for blowing out air from the air chamber 8, and 10 is a main pipe.

Explaining the operation of molding the film 2 or the like by the film 2 or the like molding apparatus having the above structure, the resin melted and extruded by the extruder not shown is the T-die 1
The film is ejected in the form of a film and wound around a rotating cooling roll 3, cooled and solidified, and then sequentially taken up by a take-up device (not shown) and trimmed at both ends and wound. The air chamber 8 blows air onto the surface of the film 2 or the like in the vicinity of a portion where the film 2 or the like contacts the cooling roll 3 to bring the film 2 or the like into close contact with the cooling roll 3 and to cool the film. The air blown from the air chamber 8 is supplied from a blower (not shown) to the main pipe 10 through the flow rate adjusting valve 7. The air is rectified from the air chamber 8 to a static pressure and blown onto the film 2 or the like to blow the film 2 or the like. Press on the cooling roll 3. At that time, the high temperature T-die 1
Immediately after being discharged from the molten resin, the molten resin content evaporates, cools and condenses at the outside air temperature, and descends as a condensed liquid on the upper plate 11a, but the upper plate 11a extends from the front edge 15 to the rear edge 16. Since it is inclined, the condensate cannot be collected in the upper plate 11a and flows in the direction of the trailing edge 16 so that the air chamber 8 does not drop into the air blowing port 9. Therefore, since the condensate is not sprayed on the film 2 etc.,
The quality of the film 2 or the like does not deteriorate.

(Second Embodiment) A second embodiment will be described with reference to FIG.

FIG. 2 is a side sectional view of this embodiment. The second embodiment is an example in which the inclination of the upper plate is formed by another member, and in FIG. 2, the upper plate 11b and the lower plate 17 of the air chamber 8a are formed.
Both a are formed parallel to the horizontal line of the cooling roll 3.
Then, on the side of the cooling roll 3, the leading edge 20 is formed on the upper plate 11b.
Lip body 2 formed in a downwardly inclined shape from the rear edge to the rear edge 21
2 is extrapolated and fixed. By using such a lip body 22, it is possible to use a conventional air chamber as the air chamber 8a, and it is possible to prevent the condensed liquid from dropping to the air blowing port 9.

As described above, according to the first and second embodiments, the upper plate 11a of the air blowing device of the film forming apparatus is
11b, the upper surface of which is from the leading edge 15, 20 to the trailing edge 16, 2.
The condensate does not drop toward the front edges 15 and 20 on the side of the film 2, which results in deterioration of the quality of the film 2 and the like. There is an advantage that it will not be done.

[0018]

Since the present invention is constructed as described above, it has the following effects.

That is, according to the apparatus for molding a film or the like of the present invention, the upper plate of the air chamber is formed to be inclined downward from the front edge to the rear edge, so that the condensed liquid of the molten resin is applied to the upper plate. It cannot be collected, flows to the trailing edge side, and does not fall into the air outlet. Therefore, the condensed liquid does not adhere to the film or the like, and the quality of the film or the like is improved.

[Brief description of drawings]

FIG. 1 is a side sectional view of a film forming apparatus according to a first embodiment of the present invention,

FIG. 2 is a side sectional view of a film forming apparatus according to a second embodiment of the present invention,

FIG. 3 is a side cross-sectional view of a conventional molding device for a film or the like.

[Explanation of symbols]

 1 T Die 2 Film 3 Cooling Roll 8, 8a Air Chamber 9 Mouth 10 Main Pipe 11a, 11b Upper Plate 15 Leading Edge 16 Trailing Edge 20 Leading Edge 21 Trailing Edge 22 Lip Body

Claims (1)

[Claims] 1. An air blowing device having an upper plate whose ceiling is arranged to cool molten resin discharged from a T-die at a winding portion of a cooling roll and to bring the molten resin into pressure contact with the cooling roll. In a film or the like forming apparatus, the film or the like forming apparatus is characterized in that the upper plate is inclined downward from a front edge to a rear edge thereof.