JP2020175659A - Die for extrusion molding - Google Patents

Abstract

To provide a die for extrusion molding, in which a width of a flow path where a molten resin passes in a lateral direction can be adjusted with high accuracy.SOLUTION: A die for extrusion molding comprises: a die body having a wall portion separating a cavity and an adjustment flow path which is a part of the flow path through which the molten resin flows and a convex portion protruding from the wall portion toward the cavity side; a slide block placed in the cavity; and an adjustment device that is connected to the slide block and moves the slide block. The convex portion comprises a first inclined surface that is inclined with respect to an inner wall facing the adjustment flow path of the wall portion. The slide block comprises a second inclined surface along the first inclined surface and in contact with the first inclined surface.SELECTED DRAWING: Figure 1

Description

The present invention relates to an extrusion die.

As an apparatus for producing a sheet formed of a thermoplastic resin, an extrusion molding apparatus including a die for molding the resin is known. In an extrusion machine, the die comprises a pair of lips. The molten resin is discharged from between the pair of lips, so that the resin is formed into a sheet. Patent Document 1 describes an example of an extrusion molding apparatus. In Patent Document 1, a flexible lip and a die bolt are provided on the die in order to control the thickness of each layer. The thickness of each layer is adjusted by the die bolt pushing and pulling the flexible lip towards the flow path.

However, in the die of Patent Document 1, the die bolt projects in a direction different from the direction in which the flow path extends. Therefore, depending on the shape of the flow path, the die bolt may interfere with other flow paths or devices arranged around the die. That is, it may be difficult to arrange the die bolts. On the other hand, Patent Document 2 describes a die having a beam-shaped block pushed and pulled by an adjusting bolt along a flow path.

Japanese Unexamined Patent Publication No. 2000-343582 Japanese Unexamined Patent Publication No. 10-217310

However, in the die of Patent Document 2, the amount of change in the width of the flow path in the lateral direction with respect to the amount of pushing and pulling the beam-shaped block is unstable. Therefore, it is difficult to improve the adjustment accuracy of the width of the flow path in the lateral direction.

The present disclosure has been made in view of the above problems, and an object of the present disclosure is to provide an extrusion molding die capable of adjusting the width of the flow path through which the molten resin passes in the lateral direction with high accuracy.

In order to achieve the above object, the extrusion molding die of one aspect of the present disclosure includes a wall portion that separates the cavity from the adjusting flow path that is a part of the flow path through which the molten resin flows, and the cavity side from the wall portion. A die body having a convex portion protruding into the cavity, a slide block arranged in the cavity, and an adjusting device connected to the slide block and moving the slide block, the convex portion of the wall portion. The slide block includes a first inclined surface that is inclined with respect to an inner wall facing the adjusting flow path, and the slide block includes a second inclined surface that is along the first inclined surface and is in contact with the first inclined surface.

As a result, by operating the first adjusting device, the second inclined surface pushes the first inclined surface with the movement of the slide block. The wall is elastically deformed so as to protrude toward the adjustment flow path side. By moving the wall portion to the adjustment flow path side, the width of the adjustment flow path in the lateral direction becomes smaller. In this way, the width of the adjustment flow path in the lateral direction can be adjusted. Further, the structure in which the second inclined surface pushes the first inclined surface stabilizes the amount of change in the width of the adjustment flow path in the lateral direction with respect to the amount of movement of the slide block. Therefore, the extrusion molding die of the present disclosure can adjust the width of the flow path through which the molten resin passes in the lateral direction with high accuracy.

As one aspect of the extrusion molding die of the present disclosure, a plurality of the slide blocks arranged along the longitudinal direction of the adjustment flow path are provided, and the plurality of the adjustments arranged along the longitudinal direction of the adjustment flow path are provided. It is desirable that the device is provided and that the position of the adjusting device in the longitudinal direction of the adjusting flow path has a one-to-one correspondence with the position of the slide block in the longitudinal direction of the adjusting flow path.

As a result, the width of the adjustment flow path in the lateral direction can be adjusted at a plurality of locations in the longitudinal direction of the adjustment flow path. Therefore, the extrusion molding die can adjust the width of the flow path in the lateral direction with high accuracy at a plurality of locations. The extrusion molding die of the present disclosure can further improve the thickness accuracy of each layer.

As one aspect of the extrusion molding die of the present disclosure, it is desirable that the width of the wall portion in the lateral direction of the adjusting flow path is 2 times or more and 4 times or less the width of the adjusting flow path in the lateral direction. ..

When the width of the wall portion is at least twice the width of the adjusting flow path, the wall portion can have a strength that does not cause damage even when pushed by the slide block. Since the width of the wall portion is 4 times or less the width of the adjustment flow path, the wall portion is easily deformed when pushed by the slide block. Therefore, the extrusion molding die of the present disclosure can achieve both the strength of the wall portion and the deformability of the wall portion.

As one aspect of the extrusion molding die of the present disclosure, it is desirable that the tangent of the angle formed by the first inclined surface with respect to the inner wall is 1/20 or more and 1/5 or less.

When the tangent of the angle formed by the first inclined surface with respect to the inner wall is 1/5 or less, fine adjustment of the amount of deformation of the wall portion becomes easy. When the tangent of the angle formed by the first inclined surface with respect to the inner wall is 1/20 or more, the amount of deformation of the wall portion per the operating amount of the first adjusting device becomes large. Therefore, in the extrusion molding die of the present disclosure, the width of the flow path in the lateral direction can be adjusted with high accuracy and the adjustment time can be shortened.

As one aspect of the extrusion molding die of the present disclosure, it is desirable that the moving direction of the slide block is parallel to the flow direction of the molten resin in the adjusting flow path.

As a result, the first adjusting device can be arranged along the adjusting flow path as compared with the case where the moving direction of the slide block intersects with the flowing direction of the molten resin. Therefore, the arrangement of the first adjusting device becomes easy. A structure in which the moving direction of the slide block is parallel to the flowing direction of the molten resin in the adjusting flow path is particularly useful for dies having a plurality of flow paths for forming a multi-layer sheet. Further, the force for operating the first adjusting device is reduced as compared with the case where the moving direction of the slide block intersects with the flowing direction of the molten resin. That is, according to the extrusion molding die of the present disclosure, the first adjusting device can be operated with a smaller force.

As one aspect of the extrusion molding die of the present disclosure, the amount of movement of the wall portion toward the adjustment flow path side by pushing the convex portion by the slide block is 0 of the width of the adjustment flow path in the lateral direction. It is desirable that it is 2 times or less.

As a result, excessive deformation of the wall portion is suppressed. The extrusion molding die of the present disclosure can suppress the occurrence of plastic deformation on the wall portion.

As one aspect of the extrusion molding die of the present disclosure, it is desirable that the width of the adjustment flow path in the longitudinal direction is constant.

Thereby, the extrusion molding die of the present disclosure can adjust the width in the lateral direction in the portion of the flow path where the width in the longitudinal direction is constant. According to the extrusion molding die of the present disclosure, the thickness of each layer of the sheet to be molded or the total thickness can be easily adjusted.

As one aspect of the extrusion molding die of the present disclosure, it is desirable to include a marking member that is connected to the slide block and is partially arranged outside the die body.

This makes it possible to specify the position of the slide block based on the position of the marking member even when the slide block cannot be seen from the die body. The position accuracy of the slide block can be further improved. Therefore, the extrusion molding die of the present disclosure can adjust the width of the flow path through which the molten resin passes in the lateral direction with higher accuracy.

As one aspect of the extrusion molding die of the present disclosure, it is desirable that the labeling member extends in a direction parallel to the moving direction of the slide block or a direction perpendicular to the moving direction of the slide block.

A through hole is required to connect the marking member to the slide block. Further, since the marking member moves together with the slide block, the through hole needs to have a size that does not interfere with the marking member. On the other hand, since the marking member extends in a direction parallel to the moving direction of the slide block or in a direction perpendicular to the moving direction of the slide block, it becomes difficult to interfere with the marking member even if the through hole is small. Therefore, the extrusion molding die of the present disclosure can be manufactured more easily because the through hole through which the labeling member is passed can be made smaller.

As one aspect of the extrusion molding die of the present disclosure, the adjusting flow path is arranged between an upstream portion, a downstream portion, and the upstream portion and the downstream portion, and is viewed from the lateral side of the adjusting flow path. In some cases, it is desirable that the intermediate portion overlaps the convex portion, and the width of the intermediate portion is smaller than the width of the upstream portion and the width of the downstream portion in the lateral direction of the adjustment flow path.

The adjusting device is operated to move the slide block, but the amount of operation of the adjusting device is limited. Therefore, it is desirable that the amount of change in the width of the adjustment flow path in the lateral direction is large per the operation amount of the adjustment device. On the other hand, if the width of the adjustment flow path in the lateral direction is reduced over the entire length, the pressure required to flow the molten resin through the flow path increases. On the other hand, in the extrusion molding die of the present disclosure, the intermediate portion near the convex portion is narrower than the upstream portion and the downstream portion. As a result, the amount of change in the width of the adjustment flow path in the lateral direction becomes large per the operation amount of the adjustment device. As a result, the adjustable range of the flow rate of the molten resin in the adjustment flow path becomes wider. Further, since the upstream portion and the downstream portion are arranged on both sides of the intermediate portion, it is possible to suppress an increase in the pressure required for flowing the molten resin into the flow path. Therefore, the extrusion molding die of the present disclosure can widen the adjustment range of the flow rate of the molten resin and can suppress an increase in the pressure required for flowing the molten resin.

According to the present invention, the width of the flow path through which the molten resin passes in the lateral direction can be adjusted with high accuracy.

FIG. 1 is a cross-sectional view of the extrusion molding die of the present embodiment. FIG. 2 is an enlarged cross-sectional view of the slide block of the present embodiment. FIG. 3 is a left side view of the extrusion molding die of the present embodiment. FIG. 4 is a cross-sectional view of the extrusion molding die of the first modification. FIG. 5 is a cross-sectional view of the extrusion molding die of the fourth modification. FIG. 6 is an enlarged cross-sectional view of the adjustment flow path of the fifth modification. FIG. 7 is a cross-sectional view taken along the line AA of FIG. FIG. 8 is an enlarged cross-sectional view of the adjustment flow path of the sixth modification. FIG. 9 is a cross-sectional view taken along the line BB of FIG.

Hereinafter, the present invention will be described in detail with reference to the drawings. The present invention is not limited to the embodiments for carrying out the following inventions (hereinafter referred to as embodiments). In addition, the components in the following embodiments include those that can be easily assumed by those skilled in the art, those that are substantially the same, that is, those in a so-called equal range. Further, the components disclosed in the following embodiments can be appropriately combined.

(Embodiment)
FIG. 1 is a cross-sectional view of the extrusion molding die of the present embodiment. FIG. 2 is an enlarged cross-sectional view of the slide block of the present embodiment. FIG. 3 is a left side view of the extrusion molding die of the present embodiment.

The extrusion molding die 20 is an apparatus for molding molten resin into a sheet. The molten resin is supplied from the extruder to the upper side of the extrusion die 20. An extruder is a device that melts and extrudes pelletized resin. The molten resin moves downward inside the extrusion molding die 20 and is discharged from the lower end portion of the extrusion molding die 20.

The extrusion die 20 is an apparatus for producing a multi-layer sheet. The multilayer sheet is a sheet formed of a plurality of types of resin layers. As shown in FIG. 1, the extrusion molding die 20 includes a die body 21, a first lip 31, a second lip 32, a slide block 40, a first adjusting device 50, a stopper 55, and a second adjustment. The device 60 is provided.

As shown in FIG. 1, the die main body 21 includes a first flow path 23, a second flow path 33, a cavity 25, a wall portion 27, and a convex portion 29. The first flow path 23 and the second flow path 33 are holes through which the molten resin flows. The die body 21 includes three first flow paths 23. Different types of molten resin are supplied to each first flow path 23. The first flow path 23 includes an introduction flow path 23a, a manifold 23b, and an adjustment flow path 23c. The introduction flow path 23a has a hole or slit shape extending in the vertical direction. The manifold 23b is connected to the downstream end of the introduction flow path 23a. The manifold 23b extends in the horizontal direction. The molten resin flowing through the introduction flow path 23a spreads in the horizontal direction when reaching the manifold 23b. The adjusting flow path 23c is connected to the downstream end of the manifold 23b. The width of the adjusting flow path 23c in the longitudinal direction (direction orthogonal to the paper surface of FIG. 1) is constant.

As shown in FIG. 1, the second flow path 33 is arranged downstream of the plurality of first flow paths 23. The molten resin that has passed through the plurality of first flow paths 23 merges at the second flow path 33. A discharge port 35, which is an opening, is provided at the downstream end of the second flow path 33. The molten resin that has passed through the second flow path 33 is discharged downward from the discharge port 35. The longitudinal direction of the discharge port 35 is parallel to the longitudinal direction of the adjusting flow path 23c. The lateral direction of the discharge port 35 is orthogonal to the lateral direction of the adjusting flow path 23c.

In the following description, the XYZ orthogonal coordinate axes are used. The X-axis is parallel to the lateral direction of the discharge port 35. The Y-axis is parallel to the longitudinal direction of the discharge port 35. The Z-axis is parallel to the discharge direction of the molten resin at the discharge port 35. The direction parallel to the X axis is described as the X direction. The direction parallel to the Y axis is described as the Y direction. The direction parallel to the Z axis is described as the Z direction. As shown in FIG. 1, the right direction when the extrusion molding die 20 is viewed from the front is defined as the + X direction. The discharge direction of the molten resin (flow direction of the molten resin in the second flow path 33) is the + Z direction. The left direction when facing the + X direction with the −Z direction facing up is the + Y direction.

As shown in FIG. 1, the cavity 25 is arranged next to the adjustment flow path 23c. The die body 21 includes a plurality of cavities 25. As shown in FIG. 1, three cavities 25 are arranged in one cross section of the die body 21 cut in the XZ plane. Further, each of the plurality of cavities 25 is a continuous cavity 25 penetrating along the Y direction. The slide blocks 40 are arranged at equal intervals along the Y direction in the penetrating continuous cavity 25.

The wall portion 27 is arranged between the cavity 25 and the adjusting flow path 23c. The wall portion 27 separates the cavity 25 from the adjusting flow path 23c. The wall portion 27 includes an inner wall 271 facing the adjusting flow path 23c. The inner wall 271 has a planar shape parallel to the XY plane. As shown in FIG. 2, the width W2 of the wall portion in the Z direction is larger than the width W1 of the adjustment flow path 23c in the Z direction. It is desirable that the width W2 is 2 times or more and 4 times or less the width W1. The width W1 is, for example, 1 mm. The width W2 is, for example, 2 mm or more and 4 mm or less.

As shown in FIG. 2, the convex portion 29 projects from the wall portion 27 toward the cavity 25 side. The convex portion 29 includes a first inclined surface 291 that is inclined with respect to the inner wall 271 of the wall portion 27. The first inclined surface 291 is inclined so as to be separated from the adjusting flow path 23c toward the downstream side of the adjusting flow path 23c. Alternatively, the first inclined surface 291 may be inclined so as to approach the adjusting flow path 23c toward the downstream side of the adjusting flow path 23c. The first inclined surface 291 forms an angle θ1 with respect to the inner wall 271. The tangent (tan θ1) of the angle θ1 is preferably 1/20 or more and 1/5 or less.

As shown in FIG. 1, the first lip 31 is arranged at the end of the die body 21 in the + Z direction. The second lip 32 is arranged at the end of the die body 21 in the + Z direction. The second lip 32 faces the first lip 31 with the discharge port 35 interposed therebetween. The first lip 31 and the second lip 32 adjacent to each other in the X direction form the discharge port 35. The lip gap, which is the width of the discharge port 35 in the X direction, changes depending on the relative positions of the first lip 31 and the second lip 32.

As shown in FIG. 1, the slide block 40 is arranged in the cavity 25. As shown in FIG. 3, the extrusion die 20 includes a plurality of slide blocks 40. The plurality of slide blocks 40 are arranged at equal intervals along the Y direction. The slide block 40 is arranged in each of the plurality of cavities 25.

As shown in FIG. 2, the slide block 40 includes a second inclined surface 41. The second inclined surface 41 is a plane along the first inclined surface 291. The second inclined surface 41 is in contact with the first inclined surface 291. The second inclined surface 41 is inclined so as to be separated from the adjusting flow path 23c toward the downstream side of the adjusting flow path 23c. Alternatively, the second inclined surface 41 may be inclined so as to approach the adjusting flow path 23c toward the downstream side of the adjusting flow path 23c. The second inclined surface 41 forms an angle θ2 with respect to the inner wall 271. The tangent (tan θ2) of the angle θ2 is preferably 1/20 or more and 1/5 or less. In this embodiment, the angle θ2 is equal to the angle θ1.

As shown in FIG. 1, the first adjusting device 50 is a device for moving the slide block 40. The first adjusting device 50 is an adjusting bolt. The first adjusting device 50 is provided on the die main body 21. A part (movable part) of the first adjusting device 50 can move in the X direction with respect to the die main body 21. One end of the first adjusting device 50 projects from the die body 21. The other end of the first adjusting device 50 is attached to the slide block 40. The slide block 40 is attached to a movable portion of the first adjusting device 50 that is movable with respect to the die body 21. When one end of the first adjusting device 50 is rotated, the other end moves in the X direction. As a result, the slide block 40 moves in the X direction. The moving direction of the slide block 40 is parallel to the flow direction of the molten resin in the adjusting flow path 23c. It is desirable that the first adjusting device 50 includes a heater. The heater makes it possible to expand and contract the first adjusting device 50. When the first adjusting device 50 includes a heater, fine adjustment of the position of the slide block 40 becomes easy.

When adjusting the thickness of each layer of the multilayer sheet formed by the extrusion die 20, the width of the adjusting flow path 23c in the Z direction is adjusted. When adjusting the width of the adjusting flow path 23c in the Z direction, the first adjusting device 50 is rotated. When the first adjusting device 50 rotates, the slide block 40 moves in the X direction. When the slide block 40 moves to the downstream side of the adjustment flow path 23c, the second inclined surface 41 pushes the first inclined surface 291 of the convex portion 29. As a result, the convex portion 29 moves toward the adjustment flow path 23c side, so that the wall portion 27 is elastically deformed so as to protrude toward the adjustment flow path 23c side. The wall portion 27 moves to the adjustment flow path 23c side. The width of the adjustment flow path 23c in the Z direction becomes smaller. As a result, the thickness of each layer of the multilayer sheet is reduced. It is desirable that the amount of movement of the wall portion 27 toward the adjustment flow path 23c side by pushing the convex portion 29 by the slide block 40 is 0.2 times or less the width W1 of the adjustment flow path 23c in the Z direction. The amount of movement of the wall portion 27 toward the adjustment flow path 23c is, for example, 0.13 mm or less. The maximum value of the amount of movement of the wall portion 27 toward the adjustment flow path 23c is defined by the stopper 55.

When the first adjusting device 50 is rotated in the reverse direction, the slide block 40 moves to the upstream side of the adjusting flow path 23c. As a result, the convex portion 29 moves toward the slide block 40 side. The deformation of the wall portion 27 returns to its original state. The width of the adjustment flow path 23c in the Z direction increases. As a result, the thickness of each layer of the multilayer sheet is increased.

As shown in FIG. 3, the extrusion die 20 includes a plurality of first adjusting devices 50. The plurality of first adjusting devices 50 are arranged at equal intervals along the Y direction. The position of the first adjusting device 50 in the Y direction corresponds one-to-one with the position of the slide block 40 in the Y direction. That is, the position of the first adjusting device 50 in the Y direction is equal to the position of the slide block 40 in the Y direction. The position of the slide block 40 can be adjusted at a plurality of positions in the Y direction by the plurality of first adjusting devices 50.

As shown in FIG. 1, the stopper 55 is attached to the first adjusting device 50. The stopper 55 is a member that regulates the movement of the first adjusting device 50 in the X direction. The stopper 55 restricts the movement of the first adjusting device 50 in the X direction by coming into contact with the surface of the die body 21.

The second adjusting device 60 is a device for changing the lip gap. As shown in FIG. 1, the second adjusting device 60 is an adjusting bolt. The second adjusting device 60 is provided on the die main body 21. One end of the second adjusting device 60 projects from the die body 21. The other end of the second adjusting device 60 is attached to the second lip 32. When one end of the second adjusting device 60 is rotated, the other end moves and the second lip 32 is elastically deformed. The second adjusting device 60 pushes and pulls the second lip 32. This changes the lip gap. It is desirable that the second adjusting device 60 includes a heater. The heater makes it possible to expand and contract the second adjusting device 60. By providing the second adjusting device 60 with a heater, fine adjustment of the lip gap becomes easy.

The extrusion molding die 20 includes a plurality of second adjusting devices 60. The plurality of second adjusting devices 60 are arranged at equal intervals along the Y direction. The position of the second adjusting device 60 in the Y direction corresponds one-to-one with the position of the slide block 40 in the Y direction. That is, the position of the second adjusting device 60 in the Y direction is equal to the position of the slide block 40 in the Y direction. The plurality of second adjusting devices 60 can adjust the lip gap at a plurality of positions in the Y direction.

When adjusting the overall thickness of the multilayer sheet formed by the extrusion die 20, the lip gap is adjusted. When adjusting the lip gap, the second adjusting device 60 is rotated. When the second adjusting device 60 rotates, the second lip 32 elastically deforms, so that the lip gap changes. As a result, the overall thickness of the multilayer sheet changes.

The extrusion molding die 20 can easily adjust the thickness of each layer of the multilayer sheet and the total thickness by operating the first adjusting device 50 and the second adjusting device 60. Therefore, the extrusion molding die 20 can easily form a desired sheet.

The cavity 25 and the slide block 40 do not necessarily have to be arranged next to all the adjustment flow paths 23c. The cavity 25 and the slide block 40 may be arranged next to at least one adjustment flow path 23c. Further, the moving direction of the slide block 40 does not necessarily have to be parallel to the flow direction of the molten resin in the adjusting flow path 23c. The moving direction of the slide block 40 may intersect with the flow direction of the molten resin in the adjusting flow path 23c.

The extrusion die 20 may be an apparatus for producing a single-layer sheet. The single-layer sheet is a sheet made of one kind of resin. In this case, the cavity 25 is arranged near the discharge port 35. The lip gap can be adjusted by the slide block 40 arranged in the cavity 25 and the first adjusting device 50.

As described above, the extrusion molding die 20 includes a die main body 21, a slide block 40, and a first adjusting device 50. The die main body 21 includes a wall portion 27 that separates the cavity 25 from the adjusting flow path 23c that is a part of the first flow path 23 through which the molten resin flows, and a convex portion 29 that protrudes from the wall portion 27 toward the cavity 25. The slide block 40 is arranged in the cavity 25. The first adjusting device 50 is connected to the slide block 40 and moves the slide block 40. The convex portion 29 includes a first inclined surface 291 that is inclined with respect to the inner wall 271 facing the adjustment flow path 23c of the wall portion 27. The slide block 40 includes a second inclined surface 41 along the first inclined surface 291 and in contact with the first inclined surface 291.

As a result, by operating the first adjusting device 50, the second inclined surface 41 pushes the first inclined surface 291 as the slide block 40 moves. The wall portion 27 is elastically deformed so as to project toward the adjustment flow path 23c side. By moving the wall portion 27 toward the adjustment flow path 23c, the width of the adjustment flow path 23c in the lateral direction becomes smaller. In this way, the width of the adjustment flow path 23c in the lateral direction can be adjusted. Further, the structure in which the second inclined surface 41 pushes the first inclined surface 291 stabilizes the amount of change in the width of the adjustment flow path 23c in the lateral direction with respect to the amount of movement of the slide block 40. Therefore, the extrusion molding die 20 of the present embodiment can adjust the width of the flow path through which the molten resin passes in the lateral direction with high accuracy.

The extrusion molding die 20 includes a plurality of slide blocks 40 arranged along the longitudinal direction (Y direction) of the adjusting flow path 23c, and a plurality of slide blocks 40 arranged along the longitudinal direction (Y direction) of the adjusting flow path 23c. A first adjusting device 50 is provided. The position of the adjustment flow path 23c of the first adjusting device 50 in the longitudinal direction (Y direction) corresponds one-to-one with the position of the adjustment flow path 23c of the slide block 40 in the longitudinal direction (Y direction).

As a result, the width of the adjusting flow path 23c in the lateral direction can be adjusted at a plurality of locations in the longitudinal direction (Y direction) of the adjusting flow path 23c. Therefore, the extrusion molding die 20 can adjust the width of the flow path in the lateral direction with high accuracy at a plurality of locations. The extrusion molding die 20 of the present embodiment can further improve the thickness accuracy of each layer.

In the extrusion molding die 20, the width W2 of the wall portion 27 in the lateral direction (Z direction) of the adjusting flow path 23c is twice or more and four times or less the width W1 in the lateral direction (Z direction) of the adjusting flow path 23c. Is.

Since the width W2 of the wall portion 27 is at least twice the width W1 of the adjusting flow path 23c, the wall portion 27 can have a strength that does not cause damage even when pushed by the slide block 40. Since the width W2 of the wall portion 27 is four times or less the width W1 of the adjustment flow path 23c, the wall portion 27 is easily deformed when pushed by the slide block 40. Therefore, the extrusion molding die 20 can achieve both the strength of the wall portion 27 and the deformability of the wall portion 27.

In the extrusion molding die 20, the tangent (tan θ1) of the angle θ1 formed by the first inclined surface 291 with respect to the inner wall 271 is 1/20 or more and 1/5 or less.

When the tangent of the angle θ1 formed by the first inclined surface 291 with respect to the inner wall 271 is 1/5 or less, the amount of deformation of the wall portion 27 can be finely adjusted. When the tangent of the angle θ1 formed by the first inclined surface 291 with respect to the inner wall 271 is 1/20 or more, the amount of deformation of the wall portion 27 per the operating amount of the first adjusting device 50 becomes large. Therefore, the extrusion molding die 20 can adjust the width of the flow path in the lateral direction with high accuracy and shorten the adjustment time.

In the extrusion molding die 20, the moving direction of the slide block 40 is parallel to the flow direction of the molten resin in the adjusting flow path 23c.

As a result, the first adjusting device 50 can be arranged along the adjusting flow path 23c as compared with the case where the moving direction of the slide block 40 intersects with the flowing direction of the molten resin. Therefore, the arrangement of the first adjusting device 50 becomes easy. The structure in which the moving direction of the slide block 40 is parallel to the flow direction of the molten resin in the adjusting flow path 23c is particularly useful for a die having a plurality of first flow paths 23 for forming a multilayer sheet. Further, the force for operating the first adjusting device 50 is reduced as compared with the case where the moving direction of the slide block 40 intersects with the flowing direction of the molten resin. That is, according to the extrusion molding die 20, the first adjusting device 50 can be operated with a smaller force.

In the extrusion molding die 20, the amount of movement of the wall portion 27 toward the adjustment flow path 23c side due to the convex portion 29 being pushed by the slide block 40 is 0.2 times or less the width of the adjustment flow path 23c in the lateral direction. Is.

As a result, excessive deformation of the wall portion 27 is suppressed. The extrusion molding die 20 can suppress the occurrence of plastic deformation on the wall portion 27.

In the extrusion molding die 20, the width of the adjusting flow path 23c in the longitudinal direction is constant.

As a result, the extrusion molding die 20 can adjust the width in the lateral direction in the portion of the first flow path 23 where the width in the longitudinal direction is constant. According to the extrusion molding die 20, the thickness of each layer of the sheet to be molded or the total thickness can be easily adjusted.

(First modification)
FIG. 4 is a cross-sectional view of the extrusion molding die of the first modification. The same components as those described in the above-described embodiment are designated by the same reference numerals, and duplicate description will be omitted.

As shown in FIG. 4, the extrusion molding die 20A of the first modification includes a die body 21A. The die body 21A includes a first flow path 24 having a shape different from that of the first flow path 23 described above. The die body 21A includes three first flow paths 24. Different types of molten resin are supplied to each first flow path 24. The first flow path 24 includes an introduction flow path 24a, a manifold 24b, and an adjustment flow path 24c. The introduction flow path 24a is a hole extending in the vertical direction. The three introduction channels 24a are arranged so as to line up in the X direction. The manifold 24b is connected to the downstream end of the introduction flow path 24a. The manifold 24b extends in the horizontal direction. The three manifolds 24b are arranged so as to line up in the X direction. The molten resin flowing through the introduction flow path 24a spreads in the horizontal direction when reaching the manifold 24b. The adjusting flow path 24c is connected to the downstream end of the manifold 24b. The width of the adjusting flow path 24c in the longitudinal direction (orthogonal direction with respect to the paper surface of FIG. 1) is constant. The lateral direction of the adjustment flow path 24c is angled with respect to the YZ plane. In the three adjustment flow paths 24c, the angles formed by the lateral direction with respect to the YZ plane are different from each other. In the three adjusting flow paths 24c, the flow directions of the molten resin are different from each other.

As shown in FIG. 4, in the die main body 21A, the cavity 25, the wall portion 27, and the convex portion 29 are arranged next to one of the three adjustment flow paths 24c. One cavity 25 is arranged in one cross section of the die body 21A cut in the XZ plane. The die body 21A includes a continuous cavity 25 penetrating along the Y direction. The slide blocks 40 are arranged at equal intervals along the Y direction in the penetrating continuous cavity 25.

When the first adjusting device 50 rotates, the slide block 40 moves in the X direction. The moving direction of the slide block 40 is parallel to the flow direction of the molten resin in the adjusting flow path 24c. When the slide block 40 moves to the downstream side of the adjustment flow path 24c, the convex portion 29 moves toward the adjustment flow path 24c side, so that the wall portion 27 is elastically deformed so as to protrude toward the adjustment flow path 24c side. .. The wall portion 27 moves to the adjustment flow path 24c side. The width of the adjusting flow path 24c in the lateral direction becomes smaller. As a result, the thickness of one of the multilayer sheets is reduced.

(Second modification)
The first adjusting device 50 can be replaced with other means such as hydraulic pressure or spring control instead of the adjusting bolt as long as it can be displaced in the X direction in FIG.

(Third modification example)
Other means can be adopted for the first inclined surface 291 of the convex portion 29 and the second inclined surface 41 of the slide block 40 as long as they exhibit the effects of the present embodiment. For example, by replacing the first inclined surface 291 with an inclined male screw and the second inclined surface 41 with a female screw corresponding to the male screw, the same effect as that of the inclined surface can be obtained. In this case, the rotational operation of the first adjusting device 50 is also transmitted to the slide block 40 as a rotational operation. Therefore, by rotating the first adjusting device 50 in the reverse direction, the action of restoring the deformation of the wall portion 27 is more reliably performed. It is also possible to intentionally expand the width W1 of the adjustment flow path 23c.

(Fourth modification)
FIG. 5 is a cross-sectional view of the extrusion molding die of the fourth modification. The same components as those described in the above-described embodiment are designated by the same reference numerals, and duplicate description will be omitted.

As shown in FIG. 5, the extrusion molding die 20B of the fourth modification includes a die body 21B and a labeling member 70. The die body 21B includes a first flow path 24 as in the first modification. In the die body 21B, the cavity 25, the wall portion 27, and the convex portion 29 are arranged next to one of the three adjustment flow paths 24c.

The die body 21B includes a through hole 211. The through hole 211 penetrates in a direction orthogonal to the flow direction of the molten resin in the adjustment flow path 24c. The through hole 211 connects the cavity 25 and the outside of the die body 21B. For example, a scale is provided on the edge of the through hole 211 on the outer side of the die body 21B.

The signing member 70 is a member indicating the position of the slide block 40. The signing member 70 is formed in a rod shape, for example. The marking member 70 penetrates through the through hole 211. One end of the marking member 70 is connected to the slide block 40. The marking member 70 extends in a direction perpendicular to the moving direction of the slide block 40. That is, the longitudinal direction of the marking member 70 is perpendicular to the moving direction of the slide block 40. The other end of the marking member 70 projects from the die body 21B. The other end of the marking member 70 is arranged outside the die body 21B. The sign member 70 can be visually recognized by a person from the outside of the die body 21B. The sign member 70 can be detected from the outside of the die body 21B by a detection device such as a camera.

When the first adjusting device 50 rotates, the slide block 40 moves in the X direction. The moving direction of the slide block 40 is parallel to the flow direction of the molten resin in the adjusting flow path 24c. When the slide block 40 moves, the sign member 70 also moves. Therefore, when the slide block 40 moves, the position of the portion of the marking member 70 outside the die body 21B changes. The position of the slide block 40 is specified based on the position of the portion of the marking member 70 outside the die body 21B. For example, it is calculated based on the position of the slide block 40, the initial position of the slide block 40 stored in advance, and the current position of the marking member 70.

The marking member 70 does not necessarily have to extend in a direction perpendicular to the moving direction of the slide block 40. The marking member 70 may extend in a direction forming an acute angle with respect to the moving direction of the slide block 40. The marking member 70 may extend in a direction parallel to the moving direction of the slide block 40. That is, the longitudinal direction of the marking member 70 may be parallel to the moving direction of the slide block 40.

As described above, the extrusion molding die 20B of the fourth modification includes a marking member 70 that is connected to the slide block 40 and is partially arranged outside the die body 21B.

This makes it possible to specify the position of the slide block 40 based on the position of the marking member 70 even when the slide block 40 cannot be seen from the die body 21B. The position accuracy of the slide block 40 can be further improved. Therefore, the extrusion molding die 20B of the fourth modification can adjust the width of the flow path through which the molten resin passes in the lateral direction with higher accuracy.

In the extrusion molding die 20B of the fourth modification, the labeling member 70 extends in a direction parallel to the moving direction of the slide block 40 or a direction perpendicular to the moving direction of the slide block 40.

A through hole 211 is required to connect the marking member 70 to the slide block 40. Further, since the sign member 70 moves together with the slide block 40, the through hole 211 needs to have a size that does not interfere with the sign member 70. On the other hand, since the marking member 70 extends in a direction parallel to the moving direction of the slide block 40 or a direction perpendicular to the moving direction of the slide block 40, it interferes with the marking member 70 even if the through hole 211 is small. It becomes difficult. Therefore, the extrusion molding die 20B of the fourth modification can be manufactured more easily because the through hole 211 through which the labeling member 70 passes can be made smaller.

(Fifth modification)
FIG. 6 is an enlarged cross-sectional view of the adjustment flow path of the fifth modification. FIG. 7 is a cross-sectional view taken along the line AA of FIG. The same components as those described in the above-described embodiment are designated by the same reference numerals, and duplicate description will be omitted.

As shown in FIG. 6, the extrusion molding die 20C of the fifth modification includes a die body 21C. The die body 21C includes a first flow path 26. The first flow path 26 is a hole through which the molten resin flows. The die body 21C includes, for example, three first flow paths 26. For example, different types of molten resin are supplied to each first flow path 26. The first flow path 26 includes an introduction flow path 26a, a manifold 26b, and an adjustment flow path 26c. The manifold 26b is connected to the downstream end of the introduction flow path 26a. The molten resin flowing through the introduction flow path 26a spreads in the Y direction when reaching the manifold 26b. The adjusting flow path 26c is arranged downstream of the manifold 26b.

As shown in FIG. 6, the adjusting flow path 26c includes an upstream portion 261, a downstream portion 263, and an intermediate portion 265. The upstream portion 261 is connected to the downstream end portion of the manifold 26b. The width W261 of the upstream portion 261 in the Z direction is substantially constant. The downstream portion 263 is arranged downstream of the upstream portion 261. The width W263 of the downstream portion 263 in the Z direction is substantially constant. For example, the width W263 is equal to the width W261. The intermediate portion 265 is arranged between the upstream portion 261 and the downstream portion 263. When viewed from the Z direction of the adjustment flow path 26c, the intermediate portion 265 overlaps the convex portion 29. The width W265 of the intermediate portion 265 in the Z direction is smaller than the width W261 and the width W263. More specifically, for example, the width W261 and the width W263 are 1.2 mm, and the width W265 is 1.1 mm.

As shown in FIG. 7, the width of the manifold 26b in the Y direction increases toward the downstream. The width of the upstream portion 261 of the adjusting flow path 26c in the Y direction increases toward the downstream. The width of the intermediate portion 265 in the Y direction is substantially constant. The width of the downstream portion 263 in the Y direction is substantially constant.

As described above, in the extrusion molding die 20C of the fifth modification, the adjustment flow path 26c is arranged between the upstream portion 261 and the downstream portion 263, and between the upstream portion 261 and the downstream portion 263, and the adjustment flow path 26c An intermediate portion 265 that overlaps the convex portion 29 when viewed from the lateral side (Z direction) of the above. In the lateral direction of the adjusting flow path 26c, the width W265 of the intermediate portion 265 is smaller than the width W261 of the upstream portion 261 and the width W263 of the downstream portion 263.

Although the first adjusting device 50 is operated to move the slide block 40, there is a limit to the amount that the first adjusting device 50 can operate. Therefore, it is desirable that the amount of change in the width of the adjustment flow path 26c in the lateral direction is large per the operation amount of the first adjustment device 50. On the other hand, if the width of the adjusting flow path 26c in the lateral direction is reduced over the entire length, the pressure required to flow the molten resin into the first flow path 26 increases. On the other hand, in the extrusion molding die 20C of the fifth modification, the intermediate portion 265 near the convex portion 29 is narrower than the upstream portion 261 and the downstream portion 263. As a result, the amount of change in the width of the adjustment flow path 26c in the lateral direction becomes large per the operation amount of the first adjustment device 50. As a result, the adjustable range of the flow rate of the molten resin in the adjusting flow path 26c becomes wider. Further, since the upstream portion 261 and the downstream portion 263 are arranged on both sides of the intermediate portion 265, it is possible to suppress an increase in the pressure required to flow the molten resin into the first flow path 26. Therefore, the extrusion molding die 20C of the fifth modification can widen the adjustment range of the flow rate of the molten resin and can suppress an increase in the pressure required for flowing the molten resin.

(6th modification)
FIG. 8 is an enlarged cross-sectional view of the adjustment flow path of the sixth modification. FIG. 9 is a cross-sectional view taken along the line BB of FIG. The same components as those described in the above-described embodiment are designated by the same reference numerals, and duplicate description will be omitted.

As shown in FIG. 8, the extrusion molding die 20D of the sixth modification includes a die body 21D. The die body 21D includes a first flow path 26D. The first flow path 26D is a hole through which the molten resin flows. The die body 21D includes, for example, three first flow paths 26D. For example, different types of molten resin are supplied to each first flow path 26D. The first flow path 26D includes an adjustment flow path 26d. The adjusting flow path 26d is arranged downstream of the manifold 26b.

As shown in FIG. 8, the adjustment flow path 26d includes an intermediate portion 267. The intermediate portion 267 is arranged between the upstream portion 261 and the downstream portion 263. When viewed from the Z direction of the adjustment flow path 26d, the intermediate portion 267 overlaps the convex portion 29. The width W267 in the Z direction of the intermediate portion 267 is smaller than the width W261 and the width W263. More specifically, for example, the width W261 and the width W263 are 1.2 mm, and the width W267 is 1.1 mm. The width of the intermediate portion 267 in the Y direction increases toward the downstream.

As described above, in the extrusion molding die 20D of the sixth modification, the adjusting flow path 26d is arranged between the upstream portion 261 and the downstream portion 263, and between the upstream portion 261 and the downstream portion 263, and the adjusting flow path 26d. An intermediate portion 267 that overlaps the convex portion 29 when viewed from the lateral side (Z direction) of the above is provided. In the lateral direction of the adjusting flow path 26d, the width W267 of the intermediate portion 267 is smaller than the width W261 of the upstream portion 261 and the width W263 of the downstream portion 263.

In the extrusion molding die 20D of the sixth modification, the intermediate portion 267 near the convex portion 29 is narrower than the upstream portion 261 and the downstream portion 263. As a result, the amount of change in the width of the adjustment flow path 26d in the lateral direction becomes large per the operation amount of the first adjustment device 50. As a result, the adjustable range of the flow rate of the molten resin in the adjusting flow path 26d becomes wider. Further, since the upstream portion 261 and the downstream portion 263 are arranged on both sides of the intermediate portion 267, it is possible to suppress an increase in the pressure required to flow the molten resin into the first flow path 26D. Therefore, the extrusion molding die 20D of the sixth modification can widen the adjustment range of the flow rate of the molten resin and can suppress an increase in the pressure required for flowing the molten resin. Further, since the width W267 in the lateral direction (Z direction) of the intermediate portion 267 increases toward the downstream, the width of the adjusting flow path 26d in the lateral direction changes per the operating amount of the first adjusting device 50. The amount will be larger.

20, 20A, 20B, 20C, 20D Extrusion molding dies 21, 21A, 21B, 21C, 21D Die body 23 1st flow path 23a Introduction flow path 23b Manifold 23c Adjustment flow path 24 1st flow path 24a Introduction flow path 24b Manifold 24c Adjustment flow path 25 Cavity 26, 26D First flow path 26a Introduction flow path 26b Manifold 26c Adjustment flow path 26d Adjustment flow path 27 Wall 29 Convex part 31 First lip 32 Second lip 33 Second flow path 35 Discharge port 40 Slide block 41 Second inclined surface 50 First adjusting device 55 Stopper 60 Second adjusting device 70 Marking member 211 Through hole 261 Upstream part 263 Downstream part 265 Intermediate part 267 Intermediate part 271 Inner wall 291 First inclined surface

Claims (10)

A wall portion that separates the cavity from the adjusting flow path that is a part of the flow path through which the molten resin flows, and a die body having a convex portion that protrudes from the wall portion toward the cavity side.
The slide block placed in the cavity and
An adjusting device connected to the slide block and moving the slide block,
With
The convex portion includes a first inclined surface that is inclined with respect to the inner wall of the wall portion that faces the adjustment flow path.
The slide block is an extrusion die having a second inclined surface along the first inclined surface and in contact with the first inclined surface. A plurality of the slide blocks arranged along the longitudinal direction of the adjustment flow path are provided.
A plurality of the adjusting devices arranged along the longitudinal direction of the adjusting flow path are provided.
The extrusion molding die according to claim 1, wherein the position of the adjusting device in the longitudinal direction of the adjusting flow path corresponds one-to-one with the position of the slide block in the longitudinal direction of the adjusting flow path. The extrusion molding die according to claim 1 or 2, wherein the width of the wall portion in the lateral direction of the adjusting flow path is 2 times or more and 4 times or less the width of the adjusting flow path in the lateral direction. The extrusion molding die according to any one of claims 1 to 3, wherein the tangent of the angle formed by the first inclined surface with respect to the inner wall is 1/20 or more and 1/5 or less. The extrusion molding die according to any one of claims 1 to 4, wherein the moving direction of the slide block is parallel to the flow direction of the molten resin in the adjusting flow path. The amount of movement of the wall portion toward the adjustment flow path side by pushing the convex portion by the slide block is 0.2 times or less the width of the adjustment flow path in the lateral direction, according to claims 1 to 5. The die for extrusion molding according to any one item. The extrusion molding die according to any one of claims 1 to 6, wherein the width of the adjustment flow path in the longitudinal direction is constant. The extrusion molding die according to any one of claims 1 to 7, further comprising a marking member connected to the slide block and partially arranged outside the die body. The extrusion molding die according to claim 8, wherein the marking member extends in a direction parallel to the moving direction of the slide block or a direction perpendicular to the moving direction of the slide block. The adjusting flow path includes an upstream portion, a downstream portion, and an intermediate portion arranged between the upstream portion and the downstream portion and overlapping the convex portion when viewed from the lateral direction of the adjusting flow path. Prepare,
The extrusion molding die according to any one of claims 1 to 9, wherein the width of the intermediate portion is smaller than the width of the upstream portion and the width of the downstream portion in the lateral direction of the adjustment flow path.

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