WO2017212538A1

WO2017212538A1 - Sheet molding die, sheet molding method, and sheet

Info

Publication number: WO2017212538A1
Application number: PCT/JP2016/066864
Authority: WO
Inventors: 富山　秀樹; 岩村　真; 政樹上田; 和哉横溝; 洋輔田子
Original assignee: 株式会社日本製鋼所
Priority date: 2016-06-07
Filing date: 2016-06-07
Publication date: 2017-12-14
Also published as: JP6711912B2; JPWO2017212538A1

Abstract

The purpose of the present invention is to provide a sheet molding die with which it is easy to adjust a forming width and a forming position of secondary material. A sheet molding die 1 comprises: a manifold 4 into which primary material is introduced and which has an opening end formed at least at one axial end thereof; a side plate 8a positioned at the at least one axial end of the manifold 4 and provided with a through-hole 9 communicating with the opening end; a plug member 3 having a nozzle 11 and a plug body 12, wherein the nozzle 11 is positioned inside the manifold 4, is provided with an inlet to which the secondary material is supplied and an outlet 18 from which the secondary material flows out, and has a smaller cross-sectional area than that of the manifold 4, and wherein the plug body 12 is at least partially accommodated in the through-hole 9, supports the nozzle 11, and is attachably/detachably supported by the side plate 8a; and a slit 5 connected to the manifold 4 and provided with an outlet for the primary material and the secondary material discharged from the manifold 4.

Description

Sheet forming die, sheet forming method and sheet

The present invention relates to a sheet forming die, a sheet forming method, and a sheet formed with the sheet forming die, and more particularly to the configuration of the sheet forming die.

A sheet of a thermoplastic resin having an encapsulation structure in which a secondary material is wrapped with a main material in a partial region in the width direction of the sheet is known. Such a sheet can be handled in the same manner as a single-layer sheet formed of only the main material because the surface properties of the sheet such as chemical resistance and adhesiveness depend on the main material.

Patent Document 1 discloses an L die that allows a main material to flow from an end portion of the die into a die manifold. A probe for supplying the secondary material is provided through the die manifold in the sheet width direction. The secondary material is discharged from the outlet of the probe and discharged together with the main material from the slit connected to the manifold, thereby forming an encapsulation structure sheet.

Patent Document 2 discloses a T-die having a probe supported at one end of a manifold and shorter than the entire length of the manifold.

Patent Document 3 discloses a T die having probes supported at both ends of a manifold. The secondary material outlet is provided at one end of the probe.

Patent Document 4 discloses a sheet forming apparatus including a flow path member that defines flow paths for a main material and a secondary material on the upstream side of a T die. The flow path member has two flow paths branched from the main material inflow path and a secondary material flow path passing between the two flow paths. An encapsulated structure sheet is formed by discharging the main material and the sub-material while the sub-material discharged from the sub-material flow path is sandwiched between the main materials discharged from the two flow paths. The

Patent Document 1: Japanese Patent No. 3241200 Patent Document 2: Japanese Patent No. 1663079 Patent Document 3: Japanese Patent No. 4686208 Patent Document 4: Japanese Patent No. 5220607

Since the secondary material is provided to give the sheet a function such as light shielding properties, high accuracy may be required for the secondary material forming width, forming position, thickness, and the like. For this reason, it may be necessary to replace the probe when adjusting the formation width, formation position, thickness, etc. of the secondary material. However, since the probes described in Patent Documents 1 to 3 are fixed to a die, replacement work is complicated. In the sheet forming apparatus described in Patent Document 4, the replacement work of the flow path member is complicated, and it is necessary to design and manufacture a flow path member having a complicated configuration.

An object of the present invention is to provide a sheet forming die capable of easily adjusting the formation width and formation position of the secondary material.

The present invention relates to a sheet forming die for forming a sheet in which a secondary material is laminated on a part of a main material. The die for sheet forming of the present invention is located at the end of at least one axial direction of the manifold, in which the main material is introduced, and at least one of the ends in the axial direction, and communicates with the open end. A side plate provided with a through-hole, an inlet located inside the manifold for supplying the secondary material, and an outlet for discharging the secondary material to the manifold, and a nozzle having a smaller cross-sectional area than the manifold, and at least partly Is inserted into the through hole, supports the nozzle, and has a plug body that is detachably supported by the side plate, and a plug member connected to the manifold and having outlets for the main material and the secondary material discharged from the manifold. And a slit provided.

According to the present invention, the plug body is detachably supported on the side plate. For this reason, when adjusting the formation width and the formation position of the secondary material, the plug body can be removed together with the nozzle supported by the plug body, and a new plug member can be attached. Therefore, according to the present invention, it is possible to provide a sheet forming die capable of easily adjusting the formation width and formation position of the secondary material.

1 is a cross-sectional view of a die according to an embodiment of the present invention. It is the A section enlarged view of FIG. It is the A section enlarged view of FIG. 1 which abbreviate | omitted illustration of the plug member. It is a perspective view of a plug member. It is sectional drawing of a nozzle. It is sectional drawing of the sheet | seat of the thermoplastic resin formed with the die | dye of this invention. It is sectional drawing of the die | dye by which the nozzle is eccentrically arranged above. It is sectional drawing of the die | dye by which the nozzle is eccentrically arranged below. It is a perspective view which shows other embodiment of a plug member. It is sectional drawing of die | dye provided with the plug member shown to FIG. 8A.

DESCRIPTION OF SYMBOLS 1 Die 2 Die plate 3,103 Plug member 4 Manifold 4a, 4b Open end 5 Slit 5a Outlet 6

Supply path

8a, 8b Side plate 9 Through-hole 11,111 Nozzle 12 Plug body 18 Outlet 21 Main material 22 Secondary material

Several embodiments of a sheet forming die (hereinafter referred to as a die 1) of the present invention will be described with reference to the drawings. In the following description, the x direction is the flow path height direction of the slit, and the y direction is the vertical direction. The z direction is a direction in which the manifold extends, and is also referred to as an axial direction or a longitudinal direction. The sheet molding die of the present invention can be suitably applied to molding of a thermoplastic resin sheet having an encapsulation structure in which a secondary material is laminated on a part of a main material. 1 is a cross-sectional view of a die cut at half the channel height between the manifold and the slit, FIG. 2 is an enlarged view of a portion A in FIG. 1, and FIG. 3 is a portion A in FIG. It is an enlarged view. In FIG. 1, the nozzle 11 is shown as an outline drawing.

The die 1 includes a die plate 2, a pair of

side plates

8a and 8b fixed to the die plate 2, and plug

members

3 and 13 attached to the

side plates

8a and 8b. The die plate 2 is a pair of molds and is fastened to each other by a bolt (not shown). A manifold 4 into which the main material is introduced and a slit 5 connected to the manifold 4 are formed inside the die plate 2 (a space between the pair of molds). The manifold 4 is a cylindrical tubular space extending substantially in the horizontal direction (z direction), and the slit 5 is a flat space extending in the vertical direction (y direction) and the z direction. The cross-sectional shape of the manifold 4 is not limited to a circle and may be a polygon such as a rectangle. In the die plate 2, a main material supply path 6 connected to the manifold 4 is formed at the longitudinal center of the manifold 4. A main material inlet 6 a is formed at the upper end of the main material supply path 6. The main material supplied from the main material supply path 6 is filled in the manifold 4.

In the present embodiment, the die 1 is a so-called T die in which the manifold 4 and the main material supply path 6 form a T-shape, but the main material supply path 6 is provided at one end of the manifold 4. It may be an L die. In addition, the T-die of the present embodiment includes the manifold 4 that extends linearly, but various known shapes such as a hanger coat type in which the flow path is bent or curved around the central portion in the longitudinal direction can be applied. .

The slit 5 is connected to the lower portion of the manifold 4 and has a width (z-direction dimension) substantially equal to the sheet width. The slit 5 is connected to the manifold 4 and has an outlet 5a for the main material and the auxiliary material at the lower end. The pressurized resin in the manifold 4 flows into the slit 5 from the connecting portion 7 between the manifold 4 and the slit 5, and is discharged from the outlet 5a.

The ends on both sides in the longitudinal direction (z direction) of the manifold 4 are

open ends

4a and 4b. Further, a pair of

side plates

8 a and 8 b are provided on both sides of the die plate 2 in the longitudinal direction (z direction) of the manifold 4, that is, on the axial end of the manifold 4. The

side plates

8a and 8b are provided with through holes 9 communicating with the

open ends

4a and 4b of the manifold 4 (see FIG. 3). The through hole 9 of one side plate 8a is closed by a first plug member 3 to which a secondary material is supplied, and the through hole 9 of the other side plate 8b is a second plug member 13 to which no secondary material is supplied. It is blocked by. The second plug member 13 has an insertion portion 13 a that is inserted into the manifold 4. The insertion portion 13 a has an upper portion that is longer than the lower portion so that the width (dimension in the z direction) of the internal space of the manifold 4 gradually increases toward the slit 5. Instead of providing the second plug member 13, the opening end 4b of the manifold 4 to which the secondary material is not supplied may be closed with a side plate having no opening. Further, the manifold 4 may have an opening end 4 a only at one axial end, and the other axial end may be closed by the die plate 2. That is, it is only necessary that an opening end is formed at at least one axial end of the manifold 4. When the secondary material is formed on both sides of the sheet, the first plug members 3 may be provided in the through holes 9 on both sides. A side plate packing 10 is inserted between the die plate 2 and the

side plates

8a and 8b to prevent resin leakage. Hereinafter, the first plug member 3 is simply referred to as a plug member 3.

The through hole 9 of the side plate 8 a is coaxial with the opening end 4 a of the manifold 4, and the inner diameter gradually increases as the distance from the manifold 4 increases. Specifically, as shown in FIG. 3, the through hole 9 of the side plate 8a includes a first portion 9a on the manifold 4 side, a third portion 9c on the outer surface side of the side plate 8a, and a first portion 9a. And a second portion 9b located between the third portions 9c. The inner diameter of the first portion 9a is substantially equal to the inner diameter of the manifold 4, the inner diameter of the second portion 9b is larger than the inner diameter of the first portion 9a, and the inner diameter of the third portion 9c is larger than the inner diameter of the second portion 9b. large. Between the first portion 9a and the second portion 9b of the through hole 9 of the side plate 8a, a first surface 8c located in the xy plane is formed. A second surface 8d parallel to the first surface 8c is formed between the second portion 9b and the third portion 9c of the through hole 9 of the side plate 8a. Although description is omitted, the side plate 8b has the same configuration as the side plate 8a.

4 is a perspective view of the plug member 3, and FIG. 5 is a cross-sectional view taken along the line AA of FIG. The plug member 3 is mounted in the through hole 9 of the side plate 8a. The plug member 3 includes a nozzle 11 having an outlet 18 through which the secondary material flows out, and a plug body 12 that supports the nozzle 11 and is detachably held on the side plate 8a. In order to increase the strength of the nozzle 11, the nozzle 11 is integrally formed with the plug body 12 by cutting or the like. The wall thickness of the nozzle 11 may be increased toward the plug body 12 in order to suppress stress concentration at the connection portion 14 with the plug body 12. The nozzle 11 and the plug body 12 have a circular cross section, but may be polygonal or elliptical.

Inside the nozzle 11, a flow path 15 through which a secondary material flows is provided. As shown in FIG. 2, the flow path 15 communicates with the flow path 16 of the plug body 12 at the inlet 15 a, and the flow path 16 is connected to an external secondary material supply source (not shown) by a pipe 17. ing. On the lower surface of the nozzle 11 facing the connecting portion 7 between the die plate 2 and the slit 5, a secondary material outlet 18 communicating with the flow path 15 is provided. Therefore, the secondary material is supplied from the supply source through the pipe 17 and the flow path 16 to the nozzle 11 from the inflow port 15 a and discharged from the outflow port 18. The outlet 18 is an elongated opening extending in the axial direction z of the nozzle 11, and its length and position are determined according to the formation range of the secondary material. Further, the thickness of the secondary material can be adjusted by adjusting the width (frontage) in the x direction of the outlet 18. Since the outflow port 18 is provided at the lowermost part of the nozzle 11, the secondary material is discharged downward in the vertical direction.

The outer cross-sectional area of the surface of the nozzle 11 perpendicular to the z-axis is smaller than the cross-sectional area of the surface of the manifold 4 perpendicular to the z-axis, and the periphery of the nozzle 11 is the space of the manifold 4. For this reason, the main material flows around the nozzle 11 and reaches the end of the manifold 4 in the z direction. In particular, as shown in FIG. 4, in the range 19 from the vicinity of the center of the nozzle 11 in the axial direction to the tip, the nozzle 11 is gradually flattened in the x direction, whereby the main material flows around the nozzle 11. Sexuality is enhanced. As shown in FIG. 1, the secondary material flows out from the nozzle 11 in a range 27 corresponding to the length (z-direction dimension) of the outlet 18. The main material reaches the end in the longitudinal direction z of the manifold 4 and flows out of the manifold 4 in a range 28 corresponding to the length of the manifold 4 (dimension in the z direction). The secondary material flowing out from the nozzle 11 is wrapped in the main material, and a three-layered molten resin layer is formed. The molten resin layer flows into the slit 5, flows downward through the slit 5 while maintaining this state, and is discharged from the outlet 5a. Thus, a sheet-like resin 23 having an encapsulation structure in which the sub-material 22 is wrapped in the main material 21 is formed. FIG. 6 shows a cross-sectional view of the resin thus formed.

The nozzle 11 is supported only by the plug body 12. That is, no support structure such as a support leg for supporting the nozzle 11 is provided between the nozzle 11 and the inner surface of the manifold 4. Since the support structure inhibits the uniform flow of the main material, it tends to cause appearance defects such as streaking in the formed sheet, and may affect the quality of the sheet. In this embodiment, since the support structure which inhibits the flow of the main material is not provided in the manifold 4, such a problem is unlikely to occur. In this embodiment, the nozzle 11 having a length necessary for discharging the secondary material is supported by the plug body 12 in a cantilever structure, and it is not necessary to provide the nozzle 11 over the entire length of the manifold 4. That is, since it is not necessary to provide the nozzle 11 at a position where only the main material is formed, an adverse effect on the fluidity of the main material is suppressed.

The nozzle 11 is provided eccentrically from the central axis in the longitudinal direction of the plug main body 12 downward in the vertical direction y. As a result, the central axis in the longitudinal direction of the nozzle 11 is closer to the connecting portion 7 between the manifold 4 and the slit 5 than the central axis of the manifold 4. FIG. 7A shows an example in which the nozzle 11 is eccentrically provided on the upper side of the manifold 4. Immediately after flowing out of the nozzle 11, the secondary material is pushed toward the end of the manifold 4 by the main material that flows in the manifold 4 toward the end in the z direction. As a result, the secondary material is more easily formed on the end side of the manifold 4 than the assumed position in the sheet, and the possibility that the axial length of the secondary material is not formed as expected increases. FIG. 7B shows an example in which the nozzle 11 is eccentrically provided on the lower side of the manifold 4. Immediately after the secondary material flows out of the nozzle 11, the main material is affected in the same manner. However, since the distance between the outlet 18 of the nozzle 11, the manifold 4 and the connection portion 7 of the slit 5 is short, the secondary material is formed. Is difficult to shift in the axial direction. Therefore, the secondary material can be formed at a position assumed with higher accuracy.

As shown in FIG. 2, the plug body 12 has a shape complementary to the through hole 9 of the side plate 8a. Specifically, the plug body 12 includes three portions having different outer diameters, that is, a small diameter portion 12a, an intermediate diameter portion 12b, and a large diameter portion 12c. The small diameter portion 12a has a larger outer diameter and cross-sectional area than the nozzle 11, the medium diameter portion 12b has a larger outer diameter and cross sectional area than the small diameter portion 12a, and the large diameter portion 12c has a larger outer diameter than the medium diameter portion 12b. It has a cross-sectional area. The small diameter part 12a, the medium diameter part 12b, and the large diameter part 12c are coaxial. The small diameter portion 12a has a first end surface 12d that forms an axial end portion of the manifold 4, and the nozzle 11 extends from the first end surface 12d. The connecting portion of the medium diameter portion 12b with the small diameter portion 12a forms a second end surface 12e parallel to the first end surface 12d. A connecting portion with the middle diameter portion 12b of the large diameter portion 12c forms a third end surface 12f parallel to the first and second end surfaces 12d and 12e. Since the first end face 12d substantially coincides with the side face of the die plate 2, the length of the nozzle 11 is minimized, and the strength of the nozzle 11 is easily ensured. The small diameter portion 12a is accommodated in the first portion 9a of the through hole 9 of the side plate 8a, the medium diameter portion 12b is accommodated in the second portion 9b of the through hole 9 of the side plate 8a, and the large diameter portion 12c is the side plate. It is accommodated in the third portion 9c of the through hole 9 of 8a.

The side surface 12g adjacent to the first end surface 12d of the small diameter portion 12a is adjacent to the inner peripheral portion of the side plate packing 10 and suppresses contact between the side plate packing 10 and the main material. For this reason, the sealing effect of the side plate packing 10 can be enhanced. A plug packing 20 is provided between the first surface 8c of the side plate 8a and the second end surface 12e of the medium diameter portion 12b. The middle diameter portion 12b serves as a pressing portion that presses the plug packing 20. The plug packing 20 prevents the main material from leaking from the gap between the through hole 9 of the side plate 8a and the plug body 12.

2 and 4, the large-diameter portion 12c of the plug body 12 is provided with a plurality of through holes 28 in the circumferential direction. The second surface 8d of the side plate 8a is provided with a hole 24 formed with a thread groove that faces the through hole 28. By passing the bolt 25 through the through hole 28, engaging with the hole 24, and tightening with the nut 26, the largest third end surface 12f of the plug body 12 is in close contact with the second surface 8d of the side plate 8a. As a result, the plug body 12 is firmly fixed to the side plate 8a. By loosening the nut 26, the plug body 12 can be easily removed from the side plate 8a. In the present embodiment, the entire plug body 12 is accommodated in the through hole 9 of the side plate 8, but a part of the plug body 12 may protrude from the through hole 9 of the side plate 8a. The part should just block the through-hole 9.

FIG. 8A is a perspective view showing another embodiment 103 of the plug member. FIG. 8B is a view similar to FIGS. 7A and 7B of the embodiment shown in FIG. 8A. The nozzle 111 has a semicircular cross section having the same diameter as the manifold 4 having a circular cross section. As a result, the nozzle 111 is in contact with a part of the inner peripheral surface of the manifold 4 (in this embodiment, a length corresponding to a half circumference). The end portion of the nozzle 111 faces the central portion in the x direction of the connection portion 7 between the manifold 4 and the slit 5. Therefore, a part of the connecting portion 7 between the manifold 4 and the slit 5 communicates with the outlet 18 of the nozzle 111, and the other communicates with the internal space of the manifold 4. Since one side of the connecting portion 7 in the x direction is a flow path for the secondary material and the rest is a flow path for the primary material, the secondary material is laminated on the primary material without being surrounded by the primary material, The two-layer structure is formed. The cross-sectional shape of the nozzle 111 is not limited to a semicircle, and may be a third circle or a quarter circle. More generally, the nozzle 111 covers a portion of the connecting portion 7 between the slit 5 and the manifold 4 from one end 5b in the flow path height h direction (x direction) of the slit 5 to the middle of the flow path height h. It is sufficient that the outlet 18 of the nozzle 111 faces the portion of the connecting portion 7.

When molding a sheet, the plug member 3 is inserted into the through hole 9 and fixed to the side plate 8a. As a result, the nozzle 11 is positioned inside the manifold 4, the plug member 3 is accommodated in the through hole 9 of the side plate 8a, and the plug member 3 is mounted so as to be supported by the side plate 8a. Next, the main material is introduced into the manifold 4. At the same time, the auxiliary material is introduced into the plug member 3 and discharged from the outlet 18 of the nozzle 11. As a result, a main material introduced into the manifold 4 and a sub-material layer discharged from the outlet 18 of the nozzle 11 are formed and discharged from the outlet 18 of the slit 5. The plug member 3 can be easily replaced depending on the sheet forming condition. Since the plug body 12 can be shared by all the plug members 3, a plurality of plug members 3 having different lengths of the nozzles 11, the lengths of the outlets 18, the widths of the outlets 18 and the like may be prepared. A plurality of plug members 3 having different eccentric positions of the nozzles 11 can also be prepared.

(Example)
Several embodiments of the present invention will be described below. The die 1 used in Examples 1 to 4 and the comparative example has the same configuration as the die 1 shown in FIGS. 1 to 4, the die 1 has a width (z-direction dimension) of 270 mm, and the manifold 4 has an inner diameter of 20 mm. It is a perfect circle shape. The cross-sectional shape of the nozzle 11 is circular, the z-direction length is 67 mm, the secondary material outlet 18 is measured from the axial end surface of the manifold 4 and extends from a position of 10 mm to a position of 60 mm, and the length is 50 mm. Film-forming grade polypropylene (melt index (MI) = 3) was used as the main material and sub-material. The same raw material was used for both the main material and the secondary material, and the secondary material was colored with a pigment to observe the laminated shape of the secondary material.

Table 1 shows the parameters in Examples 1 to 4 and the comparative example together with the shape and position of the formed secondary material. In Comparative Example 1 and Examples 1 to 3, the center of the nozzle 11 coincides with the center of the manifold 4, and in Example 4, the center of the nozzle 11 is eccentric from the center of the manifold 4.

比較 In the comparative example (nozzle diameter 18 mm), only the secondary material was formed at the sheet end, and the encapsulation structure of the secondary material and the main material was not clearly seen. This is presumably because the nozzle diameter is large and the flow path of the main material in the manifold 4 becomes narrow, so that the main material is less likely to flow around the nozzle 11.

In Example 1 (nozzle diameter 16 mm), it was confirmed that the main material was laminated around the secondary material. At this time, the ratio of the cross-sectional area in the surface orthogonal to the z direction of the nozzle 11 to the cross-sectional area in the surface orthogonal to the z direction of the manifold 4 was 64%. In Example 2 (nozzle diameter 13 mm), the main material spread to the end of the manifold 4 and a relatively good encapsulation structure was obtained. In Example 3 (nozzle diameter 10 mm), a relatively good encapsulation structure was obtained as in Example 2, but the secondary material was slightly formed on the end side. This is presumably because the secondary material flowing out from the nozzle 11 was influenced by the flow of the main material and was pushed to the end of the manifold 4. In Example 4 (nozzle diameter 10 mm) in which the nozzle 11 was eccentric 3 mm from the center of the manifold 4 to the die 1 outlet side, good encapsulation was obtained and the secondary material was formed at a substantially desired position. This is presumably because the flow of the main material can be sufficiently secured to the end of the manifold 4, the main material has spread to the end of the manifold 4, and the secondary material is relatively unaffected by the flow of the main material. Is done.

In general, in the sheet forming by the T-die, the formation position of the secondary material rarely coincides with the position of the outlet 18 of the nozzle 11 because of the deformation behavior of the sheet that occurs after resin discharge from the die 1 such as neck-in. The length of the material rarely matches the length of the outlet 18 of the nozzle 11. However, as shown in the experimental results, the ratio of the cross-sectional area of the nozzle 11 to the cross-sectional area of the manifold 4 and the installation position of the nozzle 11 can be optimized in advance, and the deformation behavior of the sheet can also be analyzed beforehand. Predictable. Therefore, it is possible to design in advance the plug member 3 suitable for producing a sheet that can be obtained at a level where the accuracy of the shape and position of the secondary material can be used industrially.

The above-described Examples 1 to 4 and the comparative example are implemented by replacing the plug member 3. That is, after the experiment of one embodiment or comparative example is completed, the resin in the T die is discharged until the resin pressure drops to approximately 0 Pa, the resin pipe is removed from the plug member 3, and the plug member 3 is removed from the die 1. A new plug member 3 is removed and attached to the die 1, and a resin pipe is connected to the newly attached plug member 3. The time required for replacing the plug member 3 including these steps was about 15 minutes. Since the plug member 3 can be easily replaced, Examples 1 to 4 and the comparative example can be completed in one day. That is, since the plug member 3 can be replaced in a short time in the die 1 of the present invention, the sheet forming conditions can be optimized easily and quickly.

Table 2 shows Example 5 using the semicircular nozzle 111 shown in FIG. 8A. The nozzle diameter was 20 mm. In the present embodiment, the flow of the main material in the manifold 4 is restricted to one side, so that a two-layer laminated shape of the secondary material and the main material could be formed.

より From Examples 1 to 5 and the comparative example, in order to form a good encapsulation, it is preferable that the occupation ratio of the cross-sectional area of the nozzle 11 with respect to the cross-sectional area of the manifold 4 is 64% or less. It is more preferable that the central axis of the nozzle 11 be closer to the connecting portion 7 with the slit 5 than the center of the cross section of the manifold 4, and the secondary material becomes less susceptible to the flow of the main material, and the secondary material is more accurately positioned. Can be formed.

Since the outer diameter of the nozzle 11 is smaller than the inner diameter of the manifold 4 as described above, the nozzle 11 is affected by the flow pressure of the main material flowing around it. Although it is unlikely that the nozzle 11 itself is deformed like a bow, stress may concentrate on the base portion of the nozzle 11 connected to the plug body 12. Therefore, the stress generated in the nozzle 11 for the plug of Example 4 was obtained by analysis. First, a flow analysis was performed under the condition that a relatively high viscosity (MFR = 1.9) polypropylene was flowed at a constant temperature of 220 ° C. in a T die. Next, the internal resin pressure distribution obtained by the flow analysis was set as the pressure boundary condition of the wall surface of the T-die channel, and the structural analysis was performed to determine the stress generated in each part. The target 270 mm wide T-die generally discharges several kg to 25 kg of resin per hour, but in this analysis, a discharge amount of 100 kg per hour was assumed on the safe side. As a result of structural analysis, the maximum stress was generated at the base portion of the nozzle 11 and the value was 63.2 MPa. The yield stress of a general carbon steel material is about 350 MPa, the rolled steel material is about 200 MPa, and the yield stress of chromium molybdenum steel usually employed as a T-die member is about 835 MPa. The maximum stress obtained by the analysis was sufficiently lower than the yield stress, and it was confirmed that sufficient strength of the nozzle 11 could be secured without providing a support structure such as a support leg.

Claims

A sheet forming die for forming a sheet in which a subsidiary material is laminated on a part of a main material,
A manifold in which a main material is introduced and an open end is formed in at least one axial end;
A side plate provided with a through hole located at the at least one axial end of the manifold and communicating with the open end;
A nozzle located inside the manifold, provided with an inlet for supplying the secondary material, and an outlet for discharging the secondary material to the manifold, a nozzle having a smaller cross-sectional area than the manifold, and at least a part of the through hole A plug member that is housed in, supports the nozzle, and is detachably supported by the side plate;
A sheet forming die, comprising: a slit connected to the manifold and provided with an outlet for the main material and the secondary material discharged from the manifold.
The sheet forming die according to claim 1, wherein a cross-sectional area of the nozzle is 64% or less of a cross-sectional area of the manifold.
The sheet forming die according to claim 1 or 2, wherein the nozzle is supported only by the plug body.
4. The plug body according to claim 1, wherein the plug body has an end portion that forms an end face of the at least one axial end portion of the manifold, and the nozzle extends from the end portion. 5. Die for sheet forming.
The sheet molding according to any one of claims 1 to 4, wherein the plug body has a support surface that has an area larger than a cross-sectional area of the nozzle and is held in close contact with the side wall. Die for.
The sheet forming die according to any one of claims 1 to 5, wherein a central axis of the nozzle is closer to a connection portion between the manifold and the slit than a central axis of the manifold.
The nozzle covers a portion of the connection portion between the slit and the manifold from one end in the flow channel height direction of the slit to the middle of the flow channel height, and the outlet of the nozzle is connected to the connection portion. The sheet forming die according to any one of claims 1 to 6, which faces the portion.
A manifold having an open end at at least one axial end, a side plate having a through hole located at the at least one axial end of the manifold and communicating with the open end; and the manifold A method of forming a sheet in which a secondary material is laminated on a part of a primary material by a die for forming a sheet that is connected and has a slit provided with an outlet of the primary material and the secondary material,
A plug member having a nozzle having a smaller cross-sectional area than the manifold and a plug main body that supports the nozzle, the nozzle is located inside the manifold, and at least a part of the plug member is the through hole of the side plate. Mounted so that the plug member is supported by the side plate;
Introducing the main material into the manifold;
Introducing the secondary material into the plug member and discharging from the outlet of the nozzle;
Discharging the main material introduced into the manifold and the sub-material discharged from the outlet of the nozzle to the manifold from the outlet of the slit.
A sheet in which a secondary material is laminated on a part of a main material, which is formed by the sheet forming die according to any one of claims 1 to 7.