JP3378736B2 - Elastomer extrusion equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention can accurately form an elastomer product molded in multiple layers by using a plurality of extruders, and can be suitably used particularly for molding a thin product having a thickness of 5 mm or less. An elastomer extrusion device.

[0002]

2. Description of the Related Art In order to form a multilayer elastomer product by laminating a plurality of elastomer materials having different physical properties, a multi-extrusion device in which a plurality of extruders are arranged in parallel is used.

In such a multi-extruder, conventionally, as disclosed in, for example, Japanese Patent Application Laid-Open No. 61-291115, the elastomer material extruded from each head of a plurality of extruders is collected and discharged in one nozzle. A plurality of layers of strips are continuously formed.

However, when formed by using the above-mentioned apparatus, for example, when molding a thin elastomer product such as inner rubber of a pneumatic tire, ensure the dimensions and accuracy of the extruded elastomer product. There is a problem that is difficult.

On the other hand, Japanese Patent Publication No. 6-22848 discloses that
As shown in FIG. 12, a calender roll is provided at the extruding end of the device, and the calender roll is disclosed to improve the accuracy of the product, especially the accuracy of the thickness.

[0006]

DISCLOSURE OF THE INVENTION In this device,
Elastomer material E1, E2 extruded from each extruder
Is provided with a confluent flow passage F which merges at a confluence point P provided in the middle of the die and is pushed forward by being overlapped with each other. A downstream side of the confluent flow passage F is a finishing chamber having a small gap between the head H and the roller RO. G is formed.

However, in the merging passage F, 2
The two elastomers E1 and E2 move at substantially the same speed, but in the finishing chamber G, the elastomer material E
Since the roller 2 is in contact with the roller R0, the roller 2 is dragged by the rotation of the roller R0 and is sent at a speed V2 faster than the speed V1 of the elastomer E1.

Particularly, when the merging flow path F and the finishing chamber G are directly connected, the flow direction suddenly changes near the entrance of the finishing chamber G and the cross-sectional area of the finishing chamber G becomes narrower, so that the head H receives it. Greater flow resistance. For this reason, the speed difference is further increased, strain is generated between the layers of the two elastomers E1 and E2, and the dimension of the extruded product is likely to be distorted. Further, in this device, since the flow-through resistance becomes large, it is necessary to apply a relatively high pressure in order to push the elastomer out of the finishing chamber G, but the elastomer was pushed out because the pressure difference between the inside and outside of the device was high. This will increase the amount of expansion afterwards and further impair product accuracy.

According to the present invention, each individual flow path is opened in the extrusion space, the elastomer material is superposed under the influence of the roller, and the uniform chamber through which the overlapping material passes between the opening and the finishing chamber. Based on the interposition of the elastomer, it is possible to significantly reduce the flow resistance received from the head side while suppressing the strain between the layers of the elastomer, and it is possible to accurately separate the elastomer layers even if it is a thin elastomer product. It is an object of the present invention to provide an elastomer extrusion device capable of forming a high-quality product that retains the stability of strength without incurring the problem.

[0010]

The elastomer extrusion device of the present invention comprises a head base to which a plurality of extruder main bodies for extruding an elastomer material are connected, and an outer peripheral surface forming an extrusion space between the head base. And a driven and rotating roller, wherein the head base has a plurality of individual flow passages each having an opening through which the elastomer material extruded from each extruder body individually passes and is opened in the extrusion space. In addition, the extrusion space is a uniform chamber that progresses in the rotation direction together with the roller as an overlapping material in which the elastomer material flowing out from each of the openings is overlapped, and a section height higher than that of the uniform chamber. A finishing chamber for shaping the overlapping material into a substantially final cross-sectional shape by reducing the In the opening of each individual flow path, from the edge of the opening on the side closest to the finishing chamber to the finishing chamber to the finishing chamber, with a main portion extending with a substantially constant cross-sectional shape, The finishing chamber is provided with an extruding end for determining a product shape at the front end of a slanted narrowing portion whose cross-sectional height decreases in the direction of rotation without passing through the uniform chamber, and the extruding end of the finishing die. Width
A bulge part α is formed on both sides toward the cutting side through a thin part β for cutting.
Is characterized in that form was.

The uniform chamber has a length L of the main part.
Is preferably at least 1.5 times the sectional height T of the main portion.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION An example of an embodiment of the present invention will be described below with reference to the drawings. 1 to 9, the elastomer extrusion device 1 includes a plurality of, in this example, two sets of first and second extruder main bodies 2A and 2A for extruding the elastomer materials EA and EB.
B, a head base 3 to which the extruder main bodies 2A and 2B are connected, and an outer peripheral surface 4S that can form an extrusion space A by arranging a small gap between the head base 3 and the head base 3. It consists of a roller 4.

The two extruder main bodies 2A and 2B have substantially the same structure and are arranged diagonally intersecting each other in a vertical plane as shown in FIG. 1, and each tip is fixed to the head base body 3. ing. Each extruder main body 2A, 2B has a charging port 2
Elastomer materials EA and EB supplied from 1 are motor M
It has a well-known structure in which the screw shaft 23 driven by a gear is kneaded and melted by the rotation of the screw shaft 23 and is sent toward the head substrate 3.

The head substrate 3 is composed of the extruder main body 2A,
2B is attached to the base portion 11 and the base portion 11 is attached to the tip of the base portion 11 so as to be freely attached and detached and the outer peripheral surface 4S of the roller 4 is attached.
And the die metal fitting 12 that forms the extrusion space A between.

Further, as shown in FIG. 3, the head substrate 3 is provided with individual channels 6A and 6B for individually passing the elastomer materials EA and EB extruded from the extruders 2A and 2B. The individual flow paths 6A and 6B independently extend through the base part 11 and the die fitting 12, and at the front end thereof, openings 9A and 9B are formed which are intermittently opened in the extrusion space A. is doing.

Further, the extrusion space A has the openings 9
The elastomer materials EA and EB flowing out of A and 9B are overlapped with each other to form the overlapping material EF, and the uniform chamber 17 that advances in the rotation direction (extrusion direction) together with the roller 4, and the overlapping material EF that is continuous with the uniform chamber 17 and substantially overlaps the overlapping material EF. And a finishing chamber 16 for forming the final cross-sectional shape. The finishing chamber 16 includes the die fitting 12 and the roller 4
A small space formed between the outer peripheral surface 4S of
In this example, the push-out end 10 that determines the product shape is provided at the front end of the inclined drawing portion 16A whose cross-sectional height decreases in the direction of rotation. Note that FIG. 4 shows a flow state of the elastomer material in the extrusion space A.

Further, the die fitting 12 has the individual flow path 6
A die body 14 forming A and 6B and the uniform chamber 17, and a finishing die 1 forming the finishing chamber 16.
In this embodiment, the base 11 of the head base 3 is provided with a pressing metal fitting 32 for locking the die body 14 and the finishing die 15 together.

In the extrusion space A, a uniform chamber 17 in which the overlapping material EF flowing out from the opening 9 advances in the rotational direction together with the roller 4, and the uniform chamber 1
7 , as shown in FIGS. 2, 4, and 7,
And a finishing chamber 16 for forming the overlapping material EF into a substantially final cross-sectional shape. The finishing chamber 16 is mounted on the die body 14
And a peripheral surface 4S of the roller 4, which is a small interval portion, and in this example, at the front end of the beveled portion 16A whose cross-sectional height decreases in the rotation direction (extrusion direction), It comprises an extrusion end 10 which determines the shape.

As shown in FIG. 7, the roller 4 has a cylindrical portion having a length exceeding the maximum width W in the axial direction of the pushing space A, and keeps a constant gap with the die fitting 12. In the present embodiment, the columnar portion is provided over substantially the entire area of the roller 4, so that the roller 4 has a right columnar shape. In this embodiment, the roller 4 is driven and rotated in the counterclockwise direction in FIG. 1, that is, in the counterclockwise direction.

The uniform chamber 17 in the extrusion space A is also used.
Forms a main part 18 between the opening 9A and 9B, which is the closest to the finishing chamber 16, that is, between the opening 9A and the finishing chamber 16 in this example. More specifically, as described above, the main portion 18 is formed between the rotation-direction end edge e1 of the opening 9A and the narrowed portion 16A, and has a substantially constant cross-sectional shape over the entire length thereof.

In the uniform chamber 17, the opening 9 is provided.
The edge e2 on the opposite side of A is formed of each elastomer material EA, EB
Form a merging point P where the two merge. In this example, the uniform chamber 17 has the space between the openings 9A and 9B, so that the uniform chamber 17 connects the opening 9B and the main portion 18 between the junction P and the opening 9B. Is provided.

Therefore, the first and second extruders 2A, 2B
The respective elastomer materials EA and EB extruded from the above flow into the extruding space A from the openings 9A and 9B through the individual flow paths 6A and 6B, and merge at the confluence point P in the uniform chamber 17, After that, the main part 18 is advanced in the state of the overlapping material EF to form the final molded post-elastomeric product EG in the elastomer finishing chamber 16.

Here, the elastomer product E in this embodiment is used.
As shown in FIG. 9, G is a tire member formed by superimposing two kinds of elastomer materials having different physical properties, for example, inner rubber, and a thin strip-like elastic member having a maximum thickness To of about 2.0 mm. It is the body.

The upper layer material R is formed by the first extruder main body 2A.
Then, the lower layer material S is molded by the second extruder main body 2B. When the volume of the lower layer material S is larger than that of the upper layer material R, the screw shaft 23 of the second extruder main body 2B is made larger than that of the first extruder 2A.

In the individual flow paths 6A and 6B, the cross-sectional shape of the flow path is changed toward the downstream side so that each elastomer material E
While A and EB pass through the individual flow paths 6A and 6B, they are roughly formed.

8A, 8B, and 8C show changes in the cross-sectional shape of the elastomer material in each flow path.

FIG. 8A shows a cross-sectional shape at the entrance of the die body 14. Here, each elastomer material EA,
The EB is formed in a flat rectangular cross section, and the die main body 14
Further squeezed while passing through.

FIG. 8B shows a cross-sectional shape of the elastomer material EB when flowing through the guide passage 30. The conduit 30 is preformed into a cross-sectional shape set in consideration of the thickness ratio of the elastomer materials EA and EB in the product, that is, a shape similar to the cross-sectional shape of the elastomer EB in the product.
Note that this preforming can be performed at any position on the upstream side of the confluence point P, in the confluence point P, in the guide passage 30, the opening 9B, and near the tip of the individual flow passage 6B.

FIG. 8C shows a sectional shape of the overlapping material EF in the main portion 18. At the merging point P, the elastomer material EB flowing through the guide passage 30 has the first individual flow path 6
It merges with the elastomer material EA flowing through A to become one.
The cross-sectional shape of the elastomer material EA is also preformed in the upstream side of the confluence point P, for example, in the vicinity of the opening 9A and the tip of the individual flow path 6A, and then combined.

As described above, the elastomer extruding device 1 of the present application places the preformed elastomer material EA on the elastomer material EB which is given the motility by the roller 4 by passing through the guide passage 30. To form the overlapping material EF. That is, since the elastomer material is combined under the influence of the roller 4, the overlapping material EF previously combined in the head base body is generated in the interlayer Q as in the conventional case, compared with the case where the overlapping material EF is under the influence of the roller 4. Distortion can be suppressed.

Moreover, since the uniform chamber 17 has a substantially constant cross-sectional shape, the flow resistance received from the head substrate 3 is alleviated, and the feed rates of the elastomer materials EA and EB become substantially the same, and further, Since the change in the flow direction near the entrance of the finishing chamber 16 can be prevented, the overlapping material EF enters the finishing chamber 16 in a stable state, and the distortion of the interlayer Q can be further suppressed.

Further, the pulling force of the roller 4 acts properly over the entire length of the uniform chamber 17, and this functions as the pushing force. As a result, it becomes possible to easily extrude the elastomer from the extruding end 10 while keeping the internal pressure of the device low. Further, due to the reduction of the internal pressure, the expansion of the elastomer product EG due to the reduced pressure after being extruded from the extruding end 10 is reduced. Therefore, there is little change in shape due to this expansion, and it is possible to form a high-quality elastomer product EG which is further excellent in dimensional accuracy, bonding force, and the like. Further, the reduction of the internal pressure also contributes to the reduction of the internal temperature, the occurrence of rubber burning can be prevented, the characteristics of the material can be maintained in a good state, and the dimensional stability of the elastomer product can be improved.

In this embodiment, the uniform chamber 17 is also used.
The length L of the main portion 18 is set to be 1.5 or more of the sectional height T of the main portion 18 and exerts an effective tensile force against the overlapping material EF. If it is less than 1.5 times, the above effect may not be exhibited. The upper limit of the length L is preferably 150 mm or less. If it becomes larger than that, further improvement of the above effect is not expected,
In addition, the head base 3 becomes large, resulting in high cost and poor workability. More preferably, it is 100 mm or less.
When the cross-sectional shape of the main portion 18 is a non-rectangular shape conforming to the product shape, the maximum height in the cross-sectional shape of the main portion 18 is defined as the cross-sectional height T.

[0034] In the shape of the extrusion end 10 of Matatsukamatsu raised die 15, as shown in FIG. 7, the width direction both side portions, it forms a bulge α via the thin portion beta.

The elastomer material is passed through the finishing die 15 to be extruded into a shape including the bulged portions α and α and the thin portions β and β shown by the alternate long and short dash line in FIG.
The width dimension of the elastomer product EG can be accurately formed by cutting the thin portion β using a cutting tool such as a knife , and thus the thin portion β is formed for cutting.
It

The width Wα of the bulging portion α is preferably 5 to 25 mm, and when it is less than 5 mm, the bulging portion α tends to be cut when the bulging portion α is removed. , EB becomes heavier, which is disadvantageous to workability.

The thickness tβ of the thin portion β is preferably 2.5 mm or less in consideration of the ease of cutting. The height tα of the bulge portion α is preferably 1.5tβ to 5.0tβ,
If it is less than 1.5 tβ, the bulging part α is likely to be broken during removal, and if it exceeds 5.0 tβ, the yield of the elastomer material is increased and the workability is deteriorated.

Incidentally, FIG. 10 shows the drawing unit 1 of the finishing chamber 16.
The case where 6A is the step is simply illustrated.

FIG. 11 shows another embodiment of the individual channels 6A and 6B. In the figure, first and second individual flow paths 6A,
6B are adjacent to each other at the confluence point P without any space, and the guide path 30 is excluded. Also in such a case, the elastomeric material EB of the individual flow path 6B comes into contact with the roller 4 prior to the elastomeric material EA by at least the distance 35, so that the elastomeric material EB has motility, and the elastomeric material of the elastomeric material under the influence of the roller 4 is provided. Coalescence takes place.

[0040]

As described above, the elastomer extruding device of the present invention is provided with a uniform chamber in the extruding space, and since the elastomer material is merged under the influence of the rollers, the distortion of the interlayer Q is suppressed. Furthermore, the flow resistance received from the head side can be greatly reduced. Further, it can be extruded by a small extrusion force as compared with the conventional apparatus, and even if it is a thin elastomer product, it is highly accurate and of high quality that maintains the stability of strength without causing interlayer separation of the elastomer. Can form a product. Therefore, it can be suitably used particularly for processing thin elastomer products such as tire members having a thickness of 5 mm or less.

[Brief description of drawings]

FIG. 1 is a partially sectional front view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the head base and rollers.

FIG. 3 is a cross-sectional view showing each flow path and extrusion space.

FIG. 4 is a cross-sectional view showing each flow path and extrusion space together with an elastomer material.

FIG. 5 is a perspective view showing a preformer die.

FIG. 6 is a sectional view showing the uniform chamber.

FIG. 7 is a perspective view showing the finishing chamber.

FIG. 8A is a cross-sectional view showing a cross-sectional shape of the elastomer material in the individual flow path. (B) is a cross-sectional view showing the cross-sectional shape of the elastomer material in the confluent flow path. (C) is a sectional view showing a sectional shape of the elastomer material in the uniform chamber.

FIG. 9 is a cross-sectional view showing an elastomer product molded by using the present device.

FIG. 10 is a cross-sectional view simply illustrating another shape of the finishing portion .

FIG. 11 is a cross-sectional view showing another embodiment of the individual flow path.

FIG. 12 is a cross-sectional view showing a conventional technique.

[Explanation of symbols]

2A, 2B Extruder body 3 head base 4 roller 4S outer peripheral surface 6A, 6B individual flow paths 9A, 9B opening 10 Extruded end 11 base 12 die fittings 14 die body 15 Finishing die 16 finishing room 17 uniform room 18 Main part of uniform room A extrusion space EA, EB Elastomer material EF overlapping material L length P confluence T cross section height

Claims (5)

(57) [Claims] 1. A head base to which a plurality of extruder main bodies for extruding an elastomer material are connected, and a roller which has an outer peripheral surface forming an extrusion space between the head base and is driven and rotated. The head substrate includes a plurality of individual flow passages each having an elastomer material extruded from each extruder body individually and having an opening that is interrupted in the extrusion space, and the extrusion space is The uniform material that flows in the direction of rotation together with the roller as an overlapping material in which the elastomer material that flows out from the opening overlaps is formed, and the overlapping material that is connected to this uniform room and has a cross-sectional height that is smaller than that of the uniform chamber causes the overlapping material to be substantially finished. And a finishing chamber that is formed into a cross-sectional shape, and the uniform chamber is the closest to the finishing chamber among the openings of the individual flow paths. From the rotation-side edge of the opening on the near side to the finishing chamber, a main part having a substantially constant cross-sectional shape is provided, and the finishing chamber rotates in the rotating direction without a step with the uniform chamber. The extrusion end that determines the product shape is provided at the front end of the beveled part that reduces the cross-sectional height toward, and the cutting end is cut at both sides in the width direction of the extrusion end.
An elastomer extrusion device characterized in that a bulge portion α is formed through a thin portion β for cutting. 2. The elastomer extrusion according to claim 1, wherein the uniform chamber has a substantially constant cross-sectional shape and has a main portion extending from an edge of the opening on the rotational direction side to the finishing chamber. apparatus. 3. The elastomer extrusion device according to claim 2, wherein the main part of the uniform chamber has a length L which is at least 1.5 times the sectional height T of the main part. 4. A die for forming a base portion forming the individual flow path, the merge point and the merge flow path, and forming the extrusion space between the outer peripheral surface of the roller and the head base body. The elastomer extrusion device according to claim 1 or 2, which comprises a metal fitting. 5. The die fitting comprises a preformer die that forms the merging point, a die body that forms the merging passage and a uniform chamber, and a finishing die that forms the finishing chamber. The elastomer extrusion device according to claim 4.