JPH1024481A - T-die for extrusion - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a T-die for extrusion which is capable of being favorably applied to an extremely thin-wall sheet in particular without spoiling the quality of a product and production efficiency by providing a bending function in a lip part. SOLUTION: Molten resin is extruded from a flow path 20 passing through a feed path 10, a manifold part 12, a die land part 14, a lip land part 16 and a lip part 18 and molded into an extremely thin-wall sheet and/or a film. In the T-die, an inner deckle 30 is formed into an integral shape over a parallel straight type manifold part 12b and the die land part 14. In the fitting part of an outer deckle 40, the lip part is formed into a guide sliding groove and also a controlling means of sealing pressure is provided in the sealing part thereof. Respective supporting rods 32, 50 of both deckles are constituted so as to be moved in the front and rear directions through a moving block 62 and a motor 66.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a sheet and / or film (hereinafter, referred to as "melt plastic material") such as synthetic resin.
The present invention relates to a T-die for extruding a sheet so as to be adjustable in sheet width, and more particularly to a T-die which has a bending function on a lip portion thereof and can be suitably applied to an extremely thin sheet.

[0002]

2. Description of the Related Art Generally, molten plastic materials (molten resins, etc.)
As shown in FIGS. 6 and 7, for example, a T-die for extruding a sheet from a central part supply passage 10 symmetrically in the left-right direction and sequentially in the extrusion direction, a manifold part 12, a die land part 14, a lip land part 16, and a It is formed as a part 18. Then, the molten resin is sequentially extruded from each of the flow paths 20 passing through the supply path 10 and each of the parts 12 to 18 to be formed into a sheet. In this case, usually, a means (Dickel) for regulating the width of the flow path 20 is provided on both sides of the T-die, and a means for regulating the extrusion width is provided on the lip 18. And
Thus, the sheet thickness and width L are set to predetermined values.

When such a T-die is applied to a sheet having an extremely thin thickness (generally, 2 mm or less), the deckle (sheet width regulating means) is usually provided in the manifold section 12. Buried in the inner deckle 2
2 and an outer deckle 24 provided on the lip portion 18, and the lip width regulating means comprises a thickness adjusting bending mechanism 26 to which one of the lip pieces 18a is bent. These are intended to maintain the quality and production efficiency of the product even for an extremely thin sheet.

The reason why the inner deckle 22 generally does not extend into the land portion (the die land portion 14 and the lip land portion 16) is that the inner deckle 22 does not extend into the land portion (particularly, the lip land portion 16). This is because there is a possibility that various problems may occur if the flow path 20 is extended because the gap of the flow path 20 is narrow.

[0005]

However, the above-described conventional T-die for extrusion molding, that is, a T-die having a lip portion with a bending function and having an inner deckle and an outer deckle (hereinafter referred to as a T-die for an extremely thin sheet). Dies or simply T dies) still had the following drawbacks.

However, as described above, the conventional T-die for an ultra-thin sheet is provided with a lip portion with a bending function, an inner deckle and an outer deckle, so that it can be applied to an extremely thin sheet. ,
It is intended to maintain good product quality and production efficiency. However, depending on the configuration, the quality and production efficiency of the product were not actually maintained well.

That is, the quality and / or production efficiency of this type of product is such that, for example, the flow resistance between the flow paths 20 is as equal as possible (identity of resistance between flow paths), Of the molten resin stays inside the T-die and is not fixed (the non-fixing property of the molten resin), the shape of both ends of the sheet width is stabilized (the stability of the product shape), and the work of adjusting the sheet width L is easy. Each condition such as a certain condition (ease of sheet width adjustment work) is required. However, the conventional T
None of the dies could achieve all or some of the above conditions.

For example, since the length of the manifold section 12 differs between the flow paths 20, the non-sticking property of the molten resin is the same as the resistance between flow paths. Due to the sticking, the stability of the product shape is attributable to the relative position of the inner deckle 22 and the outer deckle 24 being fixedly set. In general, each (or at least some of them)
Had not been achieved.

Accordingly, an object of the present invention is to provide a lip portion with a bending function so that it can be suitably applied to an extremely thin sheet without impairing the quality and production efficiency of the product. To provide a T-die.

[0010]

To achieve the above object, an extrusion T-die according to the present invention comprises a manifold portion, a die land portion, a lip land portion and a lip portion. In a T-die for extruding an extremely thin sheet and / or film by providing a bending function, an inner deckle is mounted on a manifold portion and a die land portion, and an outer deckle is mounted on a lip portion. It is characterized by being installed so as to be driven.

In this case, the thickness of the extremely thin sheet and / or film can be set to 2 mm or less.

The manifold section has a coat hanger type manifold section at the center and parallel straight type manifold sections on both sides, and the inner deckle is integrally formed in the parallel straight type manifold and its corresponding die land section. Can be formed.

In this case, a bleed means for discharging the staying material can be provided in the staying region of the raw molten plastic material including the lip land portion.

Further, the inner deckle and the outer deckle can be configured such that their interlocking relative positions can be adjusted.

Further, the outer deckle may have a configuration in which a guide sliding groove is provided between the outer deckle and the lip portion, and the seal portion for the lip portion is provided with adjusting means for adjusting the sealing pressure.

[0016] Preferably, the sealing pressure adjusting means includes:
It can be formed from eccentric bolts and / or elastic pressing means which adjustably press the seal packing provided on the seal portion, and the elastic pressing means can directly and / or indirectly leverage the seal packing. It can be configured to act in a manner.

In the T-die for extrusion molding according to the present invention, for example, the uniformity of the resistance between the flow paths is substantially achieved because the central portion of the manifold portion is formed in a coat hanger type. The sticking property is completely achieved by the provision of the discharge bleed means in the stagnation area, and the stability of the product shape is improved by forming the inner deckle over the manifold portion and the die land portion, And the outer deckle are configured so that their interlocking relative positions can be adjusted, and the ease of seat width adjustment work can be improved. Since the sealing pressure is configured to be adjustable, it can be reliably achieved.

That is, according to the present invention, it is clear that the product quality and production efficiency can be satisfactorily achieved even for an extremely thin sheet and / or film.

[0019]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an embodiment of a T-die for extrusion molding according to the present invention. For convenience of description, the same components as those of the conventional structure shown in FIGS. 6 and 7 are denoted by the same reference numerals, and detailed description is omitted.

1 and 2, the T according to the present invention is shown.
The die is basically similar to the conventional T die described above.
The molten resin supplied from the central supply passage 10 is sequentially extruded from each flow path 20 passing through the manifold portion 12, the die land portion 14, the lip land portion 16 and the lip portion 18, thereby forming an extremely thin wall (in general, (2 mm or less). In this case, on both sides of the T-die, an inner deckle 30 and an outer deckle 40 for regulating the width of the flow path 20 are provided, and the lip 18
Is provided with a bending mechanism 26 for regulating its thickness. And, by these, the thickness and width L of the sheet
Are respectively set to predetermined values.

However, in the present invention, in the above configuration, each deckle 30, 40 is configured as follows. Prior to this description, the bending mechanism 26 will be briefly described.

That is, the bending mechanism 26 is bent particularly at the lip land portion 16 and the lip portion 18, and the maximum thickness of the sheet is 1.7 times the total bending amount.

To explain the deckles 30 and 40, the inner deckle 30 is preferably constructed such that the manifold portion 12 preferably has a coat hanger type manifold portion 12a at the center and a parallel straight type manifold portion 12b at both sides. , And is formed integrally with the parallel straight portion 12b and the corresponding die land portion 14. In this case, the embedding of the inner deckle 30 in the die land portion 14 is as follows.
Since the bending mechanism 26 has the bending characteristics described above, the bending can be performed without any trouble.

Next, the outer deckle 40 is attached to the lip portion 18 by a low friction guide plate 42.
a is formed in the guide sliding groove 42 interposed therebetween, and the sealing portion with the lip portion 18 is provided with a means 4 for adjusting the sealing pressure.
4, that is, in this embodiment, the eccentric bolt 44A that adjustably presses the seal packing 46 provided on the seal portion is
Be attached. The seal pressure adjusting means 44 may be constituted by another compression spring ball plunger 44B (see FIG. 3) or a disc spring ball plunger 44C (see FIG. 4) which can adjust the pressing force. And these are further, with respect to the seal packing 46,
3 or 4 or lever member 48
Can also act indirectly (FIG. 5).
In this case, the latter has the advantage that the space H is saved and the adjusting means 44 is arranged on the operation side, as compared with the former.

The inner deckle 30 and the outer deckle 40 configured as described above have their respective support rods 32 and 50 connected to the moving block 62 together. The support rod 32 is formed in a hollow shape, and extends while sealing the side plate 60.
In addition, the support rod 50 is configured to be able to advance and retreat in the front-rear direction via an adjustment bolt 52.

In this manner, the hollow rod 32 is
It is configured to move in the front-rear direction via a feed screw 68 driven by a motor 66 on the fixed bracket 64. That is, the inner deckle 30 and the outer deckle 40 are linked to each other, their relative positions are adjusted, and can be driven mechanically. In this drive, the seal pressure (pressing force) of the seal pressure adjusting means 44 can be adjusted (released) as needed.

Further, in the present invention, a bleed means (valve) 54 for discharging the retained resin is provided in the retained region M of the molten resin including the lip land portion 16.

Therefore, according to such a configuration, for example, the same resistance between the flow paths is substantially achieved because the central portion of the manifold portion 12 is formed in the coat hanger type 12a. In addition, the non-sticking property of the molten resin is completely achieved because the discharge bleed means 54 is provided in the stagnation area. Further, the stability of the product shape is such that the inner deckle 30 is formed over the manifold portion 12b and the die land portion 14, and the relative position of the inner deckle 30 and the outer deckle 50 is adjusted appropriately. This is achieved well. That is, both side portions of the sheet width are formed into the ear portions 72 (see FIG. 2) suitable for the stretching process in the subsequent step without forming the sharp portions 70 (see FIG. 6). The simplicity of the seat width adjustment operation is reliably achieved in a short time because the deckles 30 and 50 are mechanically driven and the outer deckle 50 is particularly configured to be able to adjust its sealing pressure. You.

Therefore, according to the present invention, it is clear that the quality and production efficiency of the product can be satisfactorily achieved even for an extremely thin sheet.

Although the present invention has been described with reference to the preferred embodiments, the present invention is not limited to the above-described embodiments, and many design changes can be made without departing from the spirit thereof.

[0031]

As described above, the extrusion-forming T-die according to the present invention comprises a manifold portion, a die land portion, a lip land portion, and a lip portion. Sheet and / or
Alternatively, in a T-die for extruding a film, an inner deckle is installed in a manifold portion and a die land portion, and an outer deckle is installed in a lip portion so as to be interlocked and mechanically driven. In addition, the shape stability of the product, the easiness of the sheet width adjusting operation, and the like can be easily and reliably achieved.

That is, according to the present invention, the product quality and production efficiency can be satisfactorily achieved even for an extremely thin sheet and / or film.

[Brief description of the drawings]

FIG. 1 is a partially enlarged cross-sectional view taken along the line II of FIG. 2 showing one embodiment of a T-die for extrusion molding according to the present invention.

FIG. 2 is a sectional view of the T-die shown in FIG. 1 taken along the line II-II.

FIG. 3 is a sectional view showing another embodiment of the outer deckle shown in FIGS. 1 and 2;

FIG. 4 is a sectional view showing still another embodiment of the outer deckle shown in FIGS. 1 and 2;

FIG. 5 is a sectional view showing still another embodiment of the outer deckle shown in FIGS. 1 and 2;

FIG. 6 is a sectional view of a conventional extrusion die T-die taken along the line VI-VI of FIG. 7;

FIG. 7 is a sectional view taken along the line VII-VII of the T-die shown in FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Supply path 12 Manifold part 14 Die land part 16 Rip land part 18 Rip part 20 Flow path 26 Bending mechanism 30 Inner deckle 32 Hollow support rod 40 Outer deckle 42 Guide sliding groove 44, 44A-44C Seal pressure adjusting means 46 Seal Packing 48 Lever member 50 Support rod 52 Adjust bolt 54 Bleed valve 60 Side plate 62 Moving block 64 Fixed bracket 66 Motor 68 Feed screw 70 Pointed part 72 Ear part

Claims (8)

[Claims] 1. A T-die comprising a manifold portion, a die land portion, a lip land portion and a lip portion, wherein a bending function is provided on the lip portion to extrude an extremely thin sheet and / or film. Inner deckle in the dieland part,
An extruding T-die, wherein outer deckles are installed on the lip so as to be interlocked and mechanically driven. 2. The extrusion die according to claim 1, wherein the ultra-thin sheet and / or film has a thickness of 2 mm or less. 3. The manifold part comprises a coat hanger type manifold part at the center part and parallel straight type manifold parts at both sides, and the inner deckle is integrally formed in the parallel straight type manifold and its corresponding die land part. 2. The extrusion-forming T according to claim 1, wherein
Die. 4. The T-die for extrusion molding according to claim 1, wherein a bleed means for discharging the staying material is provided in a staying region of the raw material molten plastic material including the lip land portion. 5. The extrusion die according to claim 1, wherein the inner deckle and the outer deckle are configured such that their interlocking relative positions can be adjusted. 6. The extrusion device according to claim 1, wherein the outer deckle has a guide sliding groove between the outer deckle and the lip portion, and the seal portion for the lip portion is provided with adjusting means for adjusting the sealing pressure. T die for molding. 7. The T-die for extrusion molding according to claim 6, wherein the seal pressure adjusting means comprises an eccentric bolt and / or an elastic pressing means for pressing the seal packing provided on the seal portion in an adjustable manner. 8. The extrusion die according to claim 7, wherein the elastic pressing means acts directly and / or indirectly on the seal packing.