Molding die and manufacturing method for molded product

Abstract

To provide a molding die having a new structure with a mechanical strength capable of withstanding a molding pressure and a high heat transfer efficiency.SOLUTION: There is provided a molding die, comprising: a temperature control circuit; and a lattice structure having repeating units formed by an aggregation of columns inside the temperature control circuit, wherein in the lattice structure, 85% or more of the columns by volume have a diameter of 0.3 mm or more and 1 mm or less, and a filling rate of the columns in the unit lattice is 5% or more and 10% or less.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a molding die and a method for manufacturing a molded article. [Background technology]

[0002] There is a known technology for manufacturing molded products with high precision by filling a mold with softened resin material and then hardening it. Injection molding is a technique in which a cavity formed by joining a mold with a cavity having a desired shape and a core having a convex shape is filled with molten resin material in the cylinder of a molding machine, pressurized, cooled and solidified, and then removed from the mold to obtain a molded product.

[0003] In the manufacturing process of such molded products, the time spent cooling the molding material, such as a molten resin material, inside the mold accounts for a large proportion of the time, which is a major factor in reducing the productivity of the manufacturing of molded products.

[0004] Here, the method of cooling the mold generally involves forming a temperature control circuit inside the mold and circulating a temperature-controlled medium such as water or oil within the temperature control circuit to cool the mold.

[0005] For example, Patent Document 1 discloses a mold having a temperature control circuit that is folded back near the end of the unevenness along the unevenness of the mold. According to Patent Document 1, in such a mold, the temperature control circuit has a shape that corresponds to the unevenness of the mold, so that partial heat accumulation can be suppressed and efficient cooling can be achieved. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2003-94440 A Summary of the Invention [Problem to be solved by the invention]

[0007] In recent years, the demand for various parts has diversified and become more functional, and the types of resins and shapes of molded products have also diversified. Some resins require rapid cooling because they are melted at high temperatures. In addition, warping and sink marks are more likely to occur when molded products have more complex shapes or are thinner, so in order to prevent this, more rapid and even cooling is required.

[0008] Thus, there is a demand for a molding die that can improve the heat transfer efficiency of the temperature control medium. However, in molding processes such as press molding and injection molding, a certain amount of pressure is applied to the die, such as the pressure of the press or injection, so a structure that has higher heat transfer efficiency while maintaining mechanical strength is required.

[0009] The present invention has been made in consideration of the above-mentioned circumstances, and has an object to provide a molding die having a new structure that has mechanical strength sufficient to withstand the pressure caused by molding and high heat transfer efficiency. [Means for solving the problem]

[0010] The present inventors have conducted extensive research to solve the above-mentioned problems. As a result, they have found that a molding die having a new structure with mechanical strength capable of withstanding molding pressure and high heat transfer efficiency can be provided by a molding die having a temperature control circuit, a lattice structure portion having repeating units formed by a collection of columns inside the temperature control circuit, and in which 85% or more of the columns in the lattice structure portion have a diameter of 0.3 mm or more and 1 mm or less on a volume basis, and the packing ratio of the columns in the unit lattice is 5% or more and 10% or less, and thus they have completed the present invention. Specifically, the present invention provides the following.

[0011] (1) Equipped with a temperature control circuit, A lattice structure having a repeating unit formed by a collection of columns is provided inside the temperature control circuit, In the lattice structure, 85% or more of the columns have a diameter of 0.3 mm or more and 1 mm or less on a volume basis, and the packing ratio of the columns in a unit lattice is 5% or more and 10% or less. Molding mold.

[0012] (2) In the lattice structure, a structure having the pillars on the side edges of a virtual bihexagonal pyramid is used as a repeating unit, The molding die according to (1), wherein the plurality of repeating units form an integral shape at the position where the vertices of the imaginary bihexagonal pyramid overlap, the bases of the imaginary hexagonal pyramids constituting the imaginary bihexagonal pyramid are arranged in a honeycomb pattern on a plane perpendicular to the height direction of each imaginary hexagonal pyramid, and columns existing at the same corners of the bases of the imaginary hexagonal pyramid form an integral shape.

[0013] (3) A molding die according to (1) or (2), in which the minimum angle between the side of the base of the virtual hexagonal pyramid and the flow direction of the temperature control medium into the lattice structure is 5° or more and 70° or less.

[0014] (4) The molding die according to (1) or (2), wherein the molding die contains a maraging steel.

[0015] (5) A molding die according to (1) or (2), having the lattice structure along at least the concave and / or convex portions of the molding die.

[0016] (6) Manufacturing a molded product using the molding die according to (1) or (2). Manufacturing method of molded products. Effect of the Invention

[0017] According to the present invention, it is possible to provide a molding die having a new structure with mechanical strength sufficient to withstand the pressure caused by molding and high heat transfer efficiency. [Brief description of the drawings]

[0018] [Figure 1] FIG. 2 is a schematic plan view showing the internal structure of the molding die according to the first embodiment. [Diagram 2] FIG. 2 is a schematic side view showing the internal structure of the molding die according to the first embodiment. [Diagram 3]FIG. 2 is a schematic front view showing the internal structure of the molding die according to the first embodiment. [Figure 4] FIG. 2 is a schematic diagram in which repeating units of the molding die according to the first embodiment are represented by lines. [Diagram 5] FIG. 2 is a perspective schematic view of a repeating unit of the molding die according to the first embodiment. [Figure 6] 1A to 1C are schematic diagrams showing a repeating unit of a molding die according to a first embodiment, as viewed from various directions. [Figure 7] FIG. 2 is a schematic diagram in which a continuous cone-shaped body of the molding die according to the first embodiment is represented by lines. [Figure 8] FIG. 2 is a schematic diagram of an integral structure formed by two continuous cones of the molding die according to the first embodiment. [Figure 9] 3 is a cross-sectional schematic diagram of a honeycomb-shaped arrangement formed by the bases of imaginary hexagonal pyramids of a plurality of continuous pyramids in the molding die according to the first embodiment. FIG. [Figure 10] FIG. 11 is a schematic plan view showing the internal structure of a molding die according to a second embodiment. [Figure 11] FIG. 11 is a schematic side view showing the internal structure of a molding die according to a second embodiment. [Figure 12] FIG. 11 is a schematic front view showing the internal structure of a molding die according to a second embodiment. [Figure 13] 3 is a schematic diagram showing the relationship between the honeycomb-shaped arrangement formed by the bases of imaginary hexagonal pyramids of a plurality of continuous pyramidal bodies in the molding die according to the first embodiment and the inflow direction of a temperature control medium. FIG. [Figure 14] 13 is a schematic diagram showing the relationship between the honeycomb-shaped arrangement formed by the bases of imaginary hexagonal pyramids of a plurality of continuous pyramidal bodies in a molding die according to a second embodiment and the inflow direction of a temperature control medium. FIG. [Figure 15] 11 is a schematic diagram for explaining the flow direction of a temperature control medium into a lattice structure portion. FIG. [Figure 16] FIG. 13 is a schematic diagram of a repeating unit of a lattice structure portion of a molding die according to another embodiment. [Figure 17]FIG. 13 is a schematic diagram of a repeating unit of a lattice structure portion of a molding die according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, an embodiment of the present invention will be described, however, the present invention is not limited to the description of the embodiment and can be carried out with appropriate modifications.

[0020] ≪Forming mold≫ The molding die according to this embodiment includes a temperature control circuit, and a lattice structure portion inside the temperature control circuit having a repeating unit formed by an assembly of columns, in which the diameter of the columns of 85% or more by volume is between 0.3 mm and 1 mm, and the filling rate of the columns in the unit lattice is between 5% and 10%.

[0021] In this specification, the term "unit cell" refers to a cell that includes one repeating unit, and is the smallest unit that constitutes a lattice structure by continuously arranging unit cells.

[0022] Each part of the molding die according to this embodiment will be described below. Note that, although a press molding die will be described below as an example, the molding die according to this embodiment is not limited to press molding, and can also be used for other molding methods such as injection molding and blow molding.

[0023] In addition, generally, a mold is used in combination with a mold in which a cavity is formed and a mold in which a core is formed, and in this case, the term "mold" refers to at least one of them.

[0024] [Mold body] The main body of the molding die according to this embodiment is made of a rigid material such as metal, and has a cavity (concave) and / or a core (convex) formed on its surface according to the desired part shape.

[0025] The material of the mold body is not particularly limited, but preferably includes, for example, maraging steel, tool steel, and stainless steel. In particular, maraging steel can be used to form a complex three-dimensional structure such as a lattice structure described later using an additive manufacturing method or the like, and has higher mechanical strength when the lattice structure described later is formed.

[0026] The size and shape of the cavity and core depend on the desired shape of the molded product, and are not particularly limited.

[0027] [Temperature control circuit] The temperature control circuit of the molding die according to this embodiment is a hollow circuit provided inside the body of the molding die, and is configured as a flow path for flowing a temperature-controlled temperature control medium such as water or oil inside the circuit. The temperature control medium flows from the outside to the inside of the molding die, transfers its temperature through the die (in the case of cooling, the temperature control medium receives heat, and in the case of heating, the temperature control medium provides heat), and then flows out to the outside. In this way, cooling or heating is performed using the difference between the temperature of the temperature control medium and the temperature of the material to be cooled, such as resin.

[0028] In the temperature control circuit, the temperature control medium may or may not be circulated. When circulating, a temperature control means is provided between the outlet and inlet of the molding die as a closed circuit, and the temperature control medium is cooled or heated again.

[0029] [Lattice structure] The lattice structure is configured inside the temperature control circuit of the molding die, and has repeating units formed by a collection of columns.

[0030] In the lattice structure of the molding die according to this embodiment, 85% or more of the columns have a diameter of 0.3 mm to 1 mm, which is relatively thin by volume, and has a large surface area and is easily in contact with water. Moreover, since the filling rate of the columns in the unit lattice is 5% to 10%, the voids are relatively large. This results in very high thermal conductivity in the lattice structure. Therefore, it is preferable to provide the lattice structure at least in the part to be cooled or heated (for example, in the case of press molding accompanied by heating, in the part where resin is present).

[0031] The diameter of the pillars of the lattice structure is not particularly limited, but is preferably 0.35 mm or more, 0.4 mm or more, 0.45 mm or more, for example. On the other hand, the diameter of a single pillar of the lattice structure is preferably 0.95 mm or less, 0.9 mm or less, 0.85 mm or less, 0.8 mm or less, 0.75 mm or less, 0.7 mm or less. In the lattice structure, it is sufficient that a proportion of the pillars described below have diameters within such ranges.

[0032] The ratio of the pillars of the lattice structure having a diameter in the above-mentioned range is not particularly limited as long as it is 85% or more, but may be, for example, 87% or more, 90% or more, 92% or more, 95% or more, 97% or more, or 99% or more. On the other hand, the ratio of the pillars of the lattice structure having a diameter in the above-mentioned range may be 100% or less (all the diameters of the pillars may be in the above-mentioned range). In one embodiment, the pillars of the lattice structure may be 100% having a diameter in the above-mentioned range. In addition, the range of the pillar diameters and the ratio of the pillars having the diameters may adopt all combinations within each range described in this specification. Furthermore, the "pillar diameter" refers to the longest distance between two points on the outline of the cross section perpendicular to the longitudinal direction of the pillar. In addition, the calculation of the pillar diameter excludes the intersections between the pillars.

[0033] For example, in a lattice structure, if the volume of the 0.5 mm pillars is 90% and the volume of the 1.2 mm pillars is 10%, it is deemed to meet the requirement that "the diameter of 85% or more of the pillars by volume is 0.3 mm or more and 1 mm or less."

[0034] The maximum length of one side of the unit lattice relative to the average diameter of the pillars of the lattice structure (maximum length of one side of the unit lattice / average diameter of the pillars) is not particularly limited, but is preferably 5.5 or more, 6 or more, 6.5 or more, 7 or more, 7.5 or more, 8 or more, 8.5 or more, 9 or more, 9.5 or more, 10 or more, 11 or more, 12 or more, 13 or more, or 14 or more. On the other hand, the maximum length of one side of the unit lattice relative to the average diameter (maximum length of one side of the unit lattice / average diameter of the pillars) is preferably 50 or less, 45 or less, 40 or less, 35 or less, 30 or less, 25 or less, or 20 or less. The "maximum length of one side of the unit lattice" refers to the length of the longest side of the unit lattice. The average diameter is calculated by dividing each pillar, excluding the intersections between the pillars, into 11 equal parts perpendicular to the length direction of the pillars, accumulating the values ​​for each of the 10 points excluding the ends, and taking the arithmetic average. If the diameters of all the pillars are the same, the diameter of the pillars is used.

[0035] The minimum length of one side of the unit lattice relative to the average diameter of the columns of the lattice structure (maximum length of one side of the unit lattice / average diameter of the columns) is preferably 5.5 or more, 6 or more, 6.5 or more, 7 or more, 7.5 or more, or 8 or more. On the other hand, the minimum length of one side of the unit lattice relative to the average diameter (minimum length of one side of the unit lattice / average diameter of the columns) is preferably 50 or less, 45 or less, 40 or less, 35 or less, 30 or less, 25 or less, 20 or less, 15 or less, 12 or less, or 10 or less. Here, the "minimum length of one side of the unit lattice" refers to the length of the smallest side of the sides of the unit lattice.

[0036] In addition, the lattice structure preferably occupies 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, or 95% or more of the surface perpendicular to the direction of travel in the temperature control circuit, and in one embodiment, the lattice structure may occupy 100% of the surface perpendicular to the direction of travel, or may occupy 100% or less, 99% or less, or 95% or less of the surface perpendicular to the direction of travel.

[0037] The shape of the pillar is not particularly limited and may be a triangular pillar, a square pillar, a cylinder, or the like.

[0038] [Lattice structure of the molding die according to the first embodiment] The lattice structure portion of the molding die of the first embodiment has a repeating unit of a structure having pillars on the side edges of a virtual bihexagonal pyramid, and the bases of the virtual hexagonal pyramids constituting the virtual bihexagonal pyramid of multiple repeating units are arranged in a honeycomb pattern on a plane perpendicular to the height direction of the virtual hexagonal pyramid, and the pillars present at the same corners of the bases of the virtual hexagonal pyramid form an integral shape.

[0039] FIG. 1 is a schematic plan view showing the internal structure of the molding die according to the first embodiment. FIG. 2 is a schematic side view showing the internal structure of the molding die according to the first embodiment. FIG. 3 is a schematic front view showing the internal structure of the molding die according to the first embodiment. For convenience of explanation, the uneven parts of the cavity and the core are omitted in FIGS. 1 to 3, and only a part of the lattice structure is shown. In the figures, the part shown with a dark mesh structure represents the pillars of the lattice structure, and is the part where the material such as metal that actually forms the lattice structure exists, and the temperature control medium passes through the parts other than the parts shown with dark colors.

[0040] 1 to 3 show a molding die 1 and a part of a temperature control circuit 2, and in particular show a part where a lattice structure portion 3 is provided. In the molding die 1 shown in Figs. 1 to 3, a temperature control circuit 2 is provided therein, and a lattice structure portion 3 is provided in a part thereof. As shown in Figs. 1 to 3, the molding die 1 has the lattice structure portion 3 along a protruding portion 11. Although Figs. 1 to 3 show an example in which the lattice structure portion 3 is formed along a protruding portion 11 of the molding die 1, the molding die may have a lattice structure portion along at least the recessed portion and / or the protruding portion depending on the shape of the desired molded product.

[0041] The shape of the lattice structure will now be described in detail.

[0042] (Repeating unit) The repeating unit is one unit that forms the lattice structure. Specifically, the repeating unit of the molding die according to the first embodiment is a structure having pillars on the side edges of an imaginary bihexagonal pyramid.

[0043] Here, the terms "virtual bihexagonal pyramid" and "virtual hexagonal pyramid" are intended to mean that no hexagonal pyramid-shaped objects such as substances or cavities exist, and refer to imaginary bihexagonal pyramid shapes and hexagonal pyramid shapes provided for convenience of explanation.

[0044] First, the repeating unit of the molding die according to the first embodiment will be described with reference to the drawings. Fig. 4 is a schematic diagram showing the repeating unit of the molding die according to the first embodiment with lines. In Fig. 4, the solid lines indicate the columns arranged on the front side of the paper, and the dashed lines indicate the columns arranged on the back side of the paper. Fig. 5 is a perspective schematic diagram of the repeating unit of the molding die according to the first embodiment.

[0045] The repeating unit 4 shown in Figures 4 and 5 has twelve pillars 41b, 42b, 43b, 44b, 45b, 46b, 41c, 42c, 43c, 44c, 45c, and 46c at positions corresponding to the side edge R of the imaginary bihexagonal pyramid H (only the position corresponding to 41b is indicated).

[0046] Here, the imaginary bihexagonal pyramid H is formed by joining two imaginary hexagonal pyramids Hb, Hc together at their imaginary bases Bb, Bc to form an integrated shape. The imaginary hexagonal pyramid Hb is formed by six pillars 41b, 42b, 43b, 44b, 45b, 46b forming an integrated shape at the vertex Vb of the imaginary hexagonal pyramid Hb. The imaginary hexagonal pyramid Hc is formed by six pillars 41c, 42c, 43c, 44c, 45c, 46c forming an integrated shape at the vertex Vc of the imaginary hexagonal pyramid Hc.

[0047] Furthermore, between the virtual hexagonal pyramids Hb and Hc, at the position where the bottom surface Bb of the virtual hexagonal pyramid Hb and the bottom surface Bc of the virtual hexagonal pyramid Hc are aligned and the corners of the hexagons of the bottom surface Bb and the bottom surface Bc overlap, pillar 41b of the virtual hexagonal pyramid Hb and pillar 41c of the virtual hexagonal pyramid Hc, pillar 42b of the virtual hexagonal pyramid Hb and pillar 42c of the virtual hexagonal pyramid Hc, pillar 43b of the virtual hexagonal pyramid Hb and pillar 43c of the virtual hexagonal pyramid Hc, pillar 44b of the virtual hexagonal pyramid Hb and pillar 44c of the virtual hexagonal pyramid Hc, pillar 45b of the virtual hexagonal pyramid Hb and pillar 45c of the virtual hexagonal pyramid Hc, and pillar 46b of the virtual hexagonal pyramid Hb and pillar 46c of the virtual hexagonal pyramid Hc each form an integral shape.

[0048] The repeating units integrally formed as described above are further integrated with other repeating units in the height direction of the imaginary hexagonal pyramids Hb and Hc to form a continuous pyramid. Fig. 7 is a schematic diagram showing the continuous pyramid of the molding die according to the first embodiment in a line. In Fig. 7, imaginary hexagonal pyramids Ha and Hd, which correspond to half of the repeating unit 4, are shown above and below the page of the repeating unit 4, respectively.

[0049] Specifically, in the continuous pyramid 5, between the virtual hexagonal pyramid Ha and the virtual hexagonal pyramid Hb, the vertex Va of the virtual hexagonal pyramid Ha is aligned with the vertex Vb of the virtual hexagonal pyramid Hb, and at the position where the vertices Va and Vb overlap, the six pillars 41a, 42a, 43a, 44a, 45a, 46a of the virtual hexagonal pyramid Ha and the six pillars 41b, 42b, 43b, 44b, 45b, 46b of the virtual hexagonal pyramid Hb form an integrated shape.

[0050] Furthermore, in the continuous pyramid 5, between the virtual hexagonal pyramids Hc and Hd, similar to the relationship between the virtual hexagonal pyramids Ha and Hb, the vertex Vc of the virtual hexagonal pyramid Hc and the vertex Vd of the virtual hexagonal pyramid Hd are aligned, and at the position where the vertices Vc and Vd overlap, the six pillars 4c1, 4c2, 4c3, 4c4, 4c5, and 4c6 of the structure 4c and the six pillars 4d1, 4d2, 4d3, 4d4, 4d5, and 4d6 of the structure 4d form an integrated shape.

[0051] In addition, in this continuous pyramid 5, it is preferable that the height directions ha, hb, hc, and hd of the virtual hexagonal pyramids Ha, Hb, Hc, and Hd are arranged in a straight line, but in one embodiment, they do not have to be arranged in a straight line. In this case, when the continuous pyramidal body 5 is viewed in a plane vertical to the height direction (a view from direction L where only the hexagon is visible), it is preferable that the columns of the multiple structures 4a, 4b, 4c, 4d forming an integral shape (six groups: group 41a, 41b, 41c, and 41d; group 42a, 42b, 42c, and 42d; group 43a, 43b, 43c, and 43d; group 43a, 43b, 44c, and 44d; group 45a, 45b, 45c, and 45d; and group 46a, 46b, 46c, and 46d) are arranged so that each group overlaps the other; however, in one embodiment, they do not have to be arranged so that each group overlaps the other.

[0052] (Integral structure of continuous cones) The continuous pyramid 5 formed in the above manner is integrated with the virtual hexagonal pyramids Ha, Hb, Hc, and Hd in the height directions ha, hb, hc, and hd. The three-dimensional integrated structure has a structure in which the height directions of the virtual hexagonal pyramid bases of the multiple continuous pyramids are aligned, and the hexagons of the virtual hexagonal pyramid bases are arranged in a honeycomb shape.

[0053] Here, "honeycomb shape" refers to a shape in which each side of one hexagon shares one side of the other hexagons, and six hexagons sharing each side are arranged around one hexagon (see Figure 9 described below).

[0054] An integral structure in which one side of the hexagonal base of one imaginary hexagonal pyramid is shared with one side of the hexagonal base of another imaginary hexagonal pyramid will be described with reference to the drawing. Fig. 8 is a schematic diagram of an integral structure formed by two continuous pyramid bodies of the molding die according to the first embodiment.

[0055] At corner portion A1 where the hexagon of base surface Bc and the hexagon of base surface Bg share one side and their respective corners meet, pillars 43b, 43c of continuous pyramid body 5 and pillars 61b, 61c of continuous pyramid body 7 form an integral structure. Similarly, at corner portion A2, pillars 44b, 44c of continuous pyramid body 5 and pillars 66b, 66c of continuous pyramid body 7 form an integral structure. Note that the structures at the top of the page are omitted in the combination of the hexagon of base surface Ba and the hexagon of base surface Be, and at the bottom of the page are omitted in the combination of the hexagon of base surface Bd and the hexagon of base surface Bh. However, if structures were placed in the omitted portions, the pillars would form an integral structure, just like the hexagon of base surface Bc and the hexagon of base surface Bg.

[0056] Fig. 9 is a cross-sectional schematic diagram of a honeycomb arrangement formed by the bases of virtual hexagonal pyramids of a plurality of continuous pyramids in the molding die according to the first embodiment. Here, the plane including the AA cross section in Fig. 8 (the plane including the bases Bc and Bg) will be described as a plane perpendicular to the height direction (ha, hb, hc, hd, see Fig. 7). As shown in Fig. 9, the continuous pyramid 5 forms an integral structure with the continuous pyramid 7, and also forms an integral structure with 12 continuous pyramids having bases Bf, Bg, Bh, Bi, Bj, Bk, Bl, Bm, Bn, Bo, Bp, Bq, Br, Bs, and Bt on the same plane.

[0057] The integral structure formed in the above manner is the lattice structure 3 shown in Figures 1 to 3. In the lattice structure 3 thus constructed, the temperature control medium collides with each of the columns as it passes through the lattice structure 3, increasing the contact between the temperature control medium and the mold, and enabling the heat of the temperature control medium to be efficiently conducted to the mold. Furthermore, such a structure has high mechanical strength and can be used without being destroyed by the pressure of pressing or injection.

[0058] [Lattice structure of the molding die according to the second embodiment] FIG. 10 is a schematic plan view showing the internal structure of the molding die according to the second embodiment. FIG. 11 is a schematic side view showing the internal structure of the molding die according to the second embodiment. FIG. 12 is a schematic front view showing the internal structure of the molding die according to the second embodiment. For convenience of explanation, the uneven parts of the cavity and the core are omitted in FIGS. 10 to 12, and only a part of the lattice structure is shown. In the figures, the part shown with a dark mesh structure represents the pillars of the lattice structure, and is the part where the material such as metal that actually forms the lattice structure exists, and the temperature control medium passes through the parts other than the parts shown with dark colors.

[0059] As is clear from a comparison of Figs. 10 to 12 (particularly Fig. 10, second embodiment) with Figs. 1 to 3 (particularly Fig. 1, first embodiment) shown above, in the schematic plan views, the internal structure of the molding die according to the second embodiment is tilted compared to the internal structure of the molding die according to the first embodiment.

[0060] Specifically, the degree of inclination is preferably such that the minimum angle between the side of the base of the virtual bihexagonal pyramid and the inflow direction of the temperature control medium into the lattice structure is 5° or more, 6° or more, 7° or more, 8° or more, 9° or more, 10° or more, 11° or more, 12° or more, 13° or more, 14° or more, 15° or more, 16° or more, 17° or more, or 18° or more. In addition, the degree of inclination is preferably such that the minimum angle between the side of the base of the virtual bihexagonal pyramid and the inflow direction of the temperature control medium into the lattice structure is 70° or less, 65° or less, 60° or less, 55° or less, 50° or less, 45° or less, 40° or less, 35° or less, 30° or less, 25° or less, or 20° or less. By inclining the virtual bihexagonal pyramid and thus the lattice structure within such an angle range, the collision of the temperature control medium with each column becomes larger, and the heat transfer efficiency can be further improved.

[0061] Here, the "minimum angle between the side of the base of the virtual hexagonal pyramid and the inflow direction of the temperature control medium into the lattice structure" will be described in more detail with reference to Figs. 13 and 14. Fig. 13 is a schematic diagram showing the relationship between the honeycomb-shaped arrangement of the bases of the virtual hexagonal pyramids of a plurality of continuous pyramids in the molding die according to the first embodiment and the inflow direction of the temperature control medium. Fig. 14 is a schematic diagram showing the relationship between the honeycomb-shaped arrangement of the bases of the virtual hexagonal pyramids of a plurality of continuous pyramids in the molding die according to the second embodiment and the inflow direction of the temperature control medium. In addition, the symbols other than bc and bc' are omitted in these figures.

[0062] In Fig. 13, among the three sides l1, l2, and l3 of the base of the virtual hexagonal pyramid, the side l2 forms the smallest angle with the inflow direction S of the temperature control medium into the lattice structure, and the specific angle is 0° (parallel). On the other hand, in Fig. 14, among the three sides l4, l5, and l6 of the base of the virtual hexagonal pyramid, the side l5 forms the smallest angle with the inflow direction S of the temperature control medium into the lattice structure, and the angle is the part shown in the figure as θ°, and this θ is "the minimum angle formed between the side of the base of the virtual hexagonal pyramid and the inflow direction of the temperature control medium into the lattice structure". There are two types of angles formed by the two lines as long as they are not parallel or perpendicular, but if there are two types, the smaller angles are compared for each of the three sides.

[0063] The direction in which the temperature control medium flows into the lattice structure is the vector direction connecting the center of gravity of the cross section of the temperature control circuit at the entrance of the lattice structure which has the smallest area, and the center of gravity of the cross section of the temperature control circuit when moved a small distance inside the lattice structure.

[0064] The flow direction of the temperature control medium into the lattice structure is explained below. Figure 15 is a schematic diagram for explaining the flow direction of the temperature control medium into the lattice structure. In Figure 15, a cylindrical temperature control circuit is used. The cross section of the temperature control circuit with the smallest area is the cross section that is parallel to and has the same shape as the bottom surface of the cylinder. The lattice structure inlet is a position that enters the lattice structure when moved an infinitesimal distance dx from here toward the lattice structure.

[0065] The center of gravity of the lattice structure inlet is the center of the cross section of the cylinder that is parallel to the bottom surface of the cylinder. The vector direction from this center point to the center of the cross section of the cylinder that is parallel to the bottom surface of the cylinder and is separated by an infinitesimal distance dx is defined as the inflow direction.

[0066] [Lattice structure of molding die according to other embodiments] 16 and 17 are schematic diagrams of repeating units of a lattice structure of a molding die according to other embodiments. The molding die of the present invention is not limited to those having the lattice structure of the molding die according to the first and second embodiments as the lattice structure, and the shape of the lattice structure is not particularly limited as long as the diameter of 85% of the columns on a volume basis is 0.3 mm or more and 1 mm or less, and the filling rate of the columns in the unit lattice is 5% or more and 10% or less.

[0067] FIG. 16(a) shows a repeating unit in which three mutually orthogonal pillars are connected at a single intersection. FIG. 16(b) shows a repeating unit in which three mutually orthogonal pillars are connected at a single intersection, and the diameter of the pillars becomes larger as they move from the intersection to the outside of the unit lattice. FIG. 16(c) shows a repeating unit in which pillars are provided at the edge of a virtual bi-quadratic pyramid, and the pillars extend from each vertex of the virtual bi-quadratic pyramid in a direction perpendicular to the tangent. FIG. 16(d) shows a repeating unit in which four pillars extend from the center of gravity of a virtual tetrahedron to the vertices, and at each vertex, four pillars extend to the vertex with the center of gravity of the virtual tetrahedron as the center of gravity of the virtual tetrahedron. FIG. 16(e) shows a repeating unit in which pillars are provided at the edges of a virtual cube. FIG. 16(f) shows a repeating unit in which pillars are provided at the edges of a virtual quadratic prism, and the vertices of two virtual quadratic prisms are integrated. In addition, complex repeating units in which geometric shapes are combined, as shown in FIG. 17(a) to (e), can also be used.

[0068] [How to use the molding die, etc.] The molding die of this embodiment can be used for any molding method, including press molding, injection molding, blow molding, etc. The molding die of this embodiment has higher heat transfer efficiency, and can therefore be used in cases where rapid or precise temperature adjustment is required, where temperature unevenness is likely to occur due to a complex shape, where warping or sink marks are likely to occur in thin-walled parts, etc.

[0069] The resin is not particularly limited, and examples of the resin that can be used include carbon fiber reinforced thermoplastics, aramid fiber composite thermoplastic resins, glass fiber composite thermoplastic materials, spider silk fiber composite thermoplastic materials, cellulose nanofiber composite thermoplastic resins, polyethylene terephthalate, polybutylene terephthalate, polyoxyethylene, polycarbonate, polyamide, polypropylene, polyethylene, polystyrene, polyphenylene sulfite, polyether ether ketone, and acrylonitrile butadiene styrene.

[0070] The present invention is not limited to the specific embodiments described above, and can be practiced with appropriate modifications within the scope that does not impair the effects of the present invention. [Explanation of symbols]

[0071] 1 Molding mold 2 Temperature control circuit 3 Lattice structure 4. Repeating Units 5,7 Continuous cone 11 Convex 41,42,43,44,45,46,41a,42a,43a,44a,45a,46a,41b,42b,43b,44b,45b,46b,41c,42c,43c,44c,45c,46c,41d,42d,43d,44d,45d,46d,61b,66b,66c,66c Pillar H Virtual bihexagonal pyramid Ha,Hb,Hc,Hd Virtual hexagonal pyramid V, Va, Vb, Vc, Vd vertices B,Ba,Bb,Bc,Bd,Be,Bf,Bg,Bh,Bi,Bj,Bk,Bl,Bm,Bn,Bo,Bp,Bq,Br,Bs,Bt Bottom R ridge A1, A2 ha,hb,hc,hd Height direction

Claims

1. Equipped with a temperature control circuit, A lattice structure having a repeating unit formed by a collection of columns is provided inside the temperature control circuit, In the lattice structure, 85% or more of the columns have a diameter of 0.3 mm or more and 1 mm or less on a volume basis, and the filling rate of the columns in a unit lattice is 5% or more and 10% or less. Molding mold.

2. In the lattice structure, a structure having the pillars on side edges of a virtual bihexagonal pyramid is used as a repeating unit, The repeating units form an integral shape at the position where the vertices of the imaginary bihexagonal pyramid overlap, and the bases of the imaginary hexagonal pyramids constituting the imaginary bihexagonal pyramid are arranged in a honeycomb shape on a plane perpendicular to the height direction of each imaginary hexagonal pyramid, and pillars existing at the same corners of the bases of the imaginary hexagonal pyramid form an integral shape. The molding die according to claim 1 .

3. The minimum angle between the side of the base of the virtual hexagonal pyramid and the flow direction of the temperature control medium into the lattice structure is 5° or more and 70° or less. The molding die according to claim 2.

4. The molding die contains maraging steel. The molding die according to claim 1 or 2.

5. The lattice structure is provided along at least the recessed and / or protruding portions of the molding die. The molding die according to claim 1 or 2.

6. A molding method for producing a molded product using the molding die according to claim 1 or 2. Manufacturing method of molded products.

Images