Method for designing a tire molding mold, tire molding mold, and method for manufacturing a tire molding mold

Abstract

To provide an efficient method for designing a tire molding die that improves strength of a tire molding die while improving performance of a sipe; a tire molding die; and a method for manufacturing a tire molding die.SOLUTION: A method for designing a tire molding die 100 is for molding a tire having a sipe formed on a tread, and determines a pattern to be a basic shape for forming the sipe as a unit cell 1 and aligns the unit cells 1 to determine the entire shape of the sipe.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for designing a tire mold, a tire mold, and a method for manufacturing a tire mold. [Background technology]

[0002] Patent Document 1 describes a sipe blade for forming grooves (sipes) with a three-dimensional structure in a tire, and a tire molding die having this sipe blade. In this sipe blade, the element shape is a three-dimensional shape consisting of two rhombic cones with a diamond-shaped base that are connected by a common side. The element shape has a three-dimensional structure that is continuous along one plane.

[0003] Patent Document 2 describes a method for manufacturing a sipe blade for a tire mold. Patent Document 2 exemplifies a high-performance sipe blade having a complex shape, such as a three-dimensional shape, in which the bent shape after bending is composed of two types of bent shapes with different developed lengths in the same direction within a single continuous shape. It also describes that the sipe blade is formed by bending. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-243644 [Patent Document 2] Japanese Patent Application Laid-Open No. 2003-145545 Summary of the Invention [Problem to be solved by the invention]

[0005] In addition to the main grooves, tires may also have numerous narrow grooves called sipes. Sipes are formed for the purposes of preventing slippage when the tire is driven on wet roads, water breaking (the action of the edges breaking the water film), improving the supply and drainage of water to the grooves and road gripping power, and adjusting the rigidity characteristics of the rubber. Because forming sipes in tires maintains the rigidity of the rubber, which in turn reduces one-sided wear, in recent years there has been a noticeable trend toward thinner sipes (thinner grooves) and more complex shapes.

[0006] As exemplified by Patent Document 2, a conventional method for manufacturing the sipe portion of a tire mold, i.e., sipe blades (an example of a tire molding mold), has been widely used, in which a rolled material of high strength (e.g., steel) is cut out and press-molded in a mold (so-called stamp molding). In recent years, direct molding methods using so-called 3D printers have also begun to be adopted. The use of 3D printers offers greater flexibility in varying the thickness of sipe blades and in accommodating complex shapes, and has the advantage of enabling shorter delivery times than stamping methods, particularly when producing a wide variety of products in small quantities, since stamp molds are not required.

[0007] However, manufacturing methods using 3D printers tend to result in lower strength and greater variation in strength compared to sipe blades manufactured by stamp molding using rolled material. Therefore, compared to manufacturing by stamp molding, this method is sometimes not suitable for mass production.

[0008] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide an efficient method for designing a tire molding mold, a tire molding mold, and a method for manufacturing a tire molding mold, which improve the strength of the tire molding mold while improving the performance of the sipes. [Means for solving the problem]

[0009] In order to achieve the above object, the method for designing a tire mold according to the present invention comprises the steps of: A method for designing a tire mold for molding a tire having sipes formed in the tread, comprising: A mold that is a basic shape for forming the sipe is defined as a unit cell, and the unit cells are arranged to define the overall shape of the sipe.

[0010] According to the above method, it is possible to provide an efficient method for designing a tire mold that improves the strength of the tire mold while improving the performance of the sipes.

[0011] According to the above method, a basic shape can be determined that improves the strength of the tire mold while improving the performance of the sipes, and this basic shape can be determined as a unit cell, which is the smallest unit of the mold shape in the portion of the tire mold that molds the sipes.Then, the overall shape of the sipes can be determined by the simple procedure of arranging these unit cells, thereby achieving the design of a tire mold with a high efficiency.

[0012] The tire mold design method according to the present invention further includes: In a direction along the axial direction of the tire, the unit cell may be provided with a thick portion having a thickness that is relatively thicker than other portions of the unit cell.

[0013] According to the above method, the thickened portion can be used to provide a portion of the sipe groove that forms a wider gap than the remaining portion. As a result, when the sipes of the tread deform due to deformation of the tire tread rubber during tire travel, the wide gap formed by the thickened portion can remain in the gap of the sipe even after the opposing inner surfaces come into contact with each other at the narrow gap portion in the sipe. This allows water absorbed from the road surface to flow through this gap.

[0014] The tire mold design method according to the present invention further includes: A protrusion may be formed on the unit cell, and the protrusion may serve as the thick portion.

[0015] Each time a tire is demolded from the mold, the mold for the sipe portion is repeatedly subjected to external forces from the sipes of the tire. According to the above method, it is possible to improve durability, for example, repeated fatigue life, against the external forces applied to the mold for the sipe portion when the tire is demolded.

[0016] The tire mold design method according to the present invention further includes: The convex portion may be formed continuously, and the thick portion may be provided along the ridge line of the convex portion.

[0017] According to the above method, water sucked up from the road surface can be made to flow through the gaps in the sipes formed along the convex portions (the gaps that remain after the opposing inner surfaces come into contact with each other in the narrow parts of the gaps within the sipes).

[0018] The tire mold design method according to the present invention further includes: The first cell, which is the first unit cell, and the second cell, which is the second unit cell adjacent to the first cell, may be arranged so that the ridge lines of the first cell and the second cell are continuous.

[0019] According to the above method, the gaps between each part of the sipe formed by adjacent unit cells (the gaps that remain after the opposing inner surfaces come into contact with each other in the narrow part of the gap within the sipe) are made continuous, and water sucked up from the road surface can be passed through these continuous gaps.

[0020] In order to achieve the above object, the tire mold according to the present invention comprises: A tire mold for molding a tire having sipes formed in the tread, Molds that are the basic shapes that form the sipes are arranged as unit cells.

[0021] The tire mold according to the present invention further comprises: The unit cell may be provided with a thick portion that is thicker than other portions of the unit cell in a direction along the axial direction of the tire.

[0022] The tire mold according to the present invention further comprises: A protrusion may be formed in the unit cell, and the protrusion may be the thick portion.

[0023] The tire mold according to the present invention further comprises: The convex portion may be formed continuously, and the thick portion may be provided along the ridge line of the convex portion.

[0024] The tire mold according to the present invention further comprises: The first cell, which is the first unit cell, and the second cell, which is the second unit cell adjacent to the first cell, may be arranged so that the ridge lines of the first cell and the second cell are continuous.

[0025] According to the above-mentioned configurations, it is possible to provide a tire mold that can improve the performance of the sipes and has improved strength, and that can be efficiently designed and manufactured. In addition, it is possible to achieve the functions or effects of the above-mentioned tire mold design method corresponding to each of the above-mentioned configurations.

[0026] In order to achieve the above object, the method for manufacturing a tire mold according to the present invention comprises the steps of: A method for manufacturing a tire mold for molding a tire having sipes formed in the tread, comprising: A mold having a basic shape for forming the sipe is arranged as a unit cell.

[0027] According to the above method, it is possible to provide an efficient method for manufacturing a tire mold that can improve the strength of the tire mold while improving the performance of the sipes, and it is also possible to achieve the functions and effects of the tire mold design method and tire mold described above. [Brief explanation of the drawings]

[0028] [Figure 1] 3A and 3B are diagrams showing the configuration of a sipe blade according to the present embodiment. [Figure 2] FIG. 2 is a perspective view showing the shape of a cell of the first embodiment. [Figure 3] FIG. 2 is a perspective view showing the shape of a cell of the first embodiment. [Figure 4] FIG. 2 is a perspective view showing the shape of a mold part of the first embodiment. [Figure 5] 4A and 4B are diagrams showing the shape of a space within a sipe formed by the mold portion of the first embodiment. [Figure 6] FIG. 10 is a perspective view showing the shape of a cell of a second embodiment. [Figure 7] FIG. 10 is a perspective view showing the shape of a mold part of a second embodiment. [Figure 8] 10A and 10B are diagrams showing the shape of a space within a sipe formed by a mold portion of a second embodiment. [Figure 9] FIG. 10 is a perspective view showing the shape of a cell according to a third embodiment. [Figure 10] FIG. 10 is a perspective view showing the shape of a cell according to a third embodiment. [Figure 11] FIG. 10 is a perspective view showing the shape of a mold part of a third embodiment. [Figure 12] 10A and 10B are diagrams showing the shape of a space within a sipe formed by a mold portion of a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0029] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for designing a tire mold, a tire mold, and a method for manufacturing a tire mold according to an embodiment of the present invention will be described with reference to the drawings.

[0030] The method for designing a tire molding die according to this embodiment relates to a method for designing a tire molding die for molding a tire having sipes formed in the tread.

[0031] 1 shows a sipe blade 100 (hereinafter referred to as blade 100) as an example of a tire molding mold according to this embodiment. The blade 100 is a mold for forming sipes (grooves) in the tread of a tire when the tire is vulcanized.

[0032] The blade 100 includes a base portion A that is fixed to a tire mold for forming the tire tread, and a mold portion B that is, for example, integrally molded with the base portion A, in which molds that form the basic shapes for forming sipes in the tire tread are arranged as unit cells 1 (hereinafter referred to as cells 1). The unit cells 1 and mold portion B are plate-shaped with a curved structure over the entire plate surface. The thickness direction of the mold portion B or unit cells 1 in the blade 100 may be aligned with the axial direction of the tire (the direction of the central axis of the ring).

[0033] In a tire mold for molding a tire tread, the blade 100 is fixed with the mold portion B disposed on the radially inner side of the tire and the base portion A disposed on the radially outer side of the tire. The plate surface of the blade 100 is fixed to the tire mold along the circumferential direction of the tire. For ease of explanation, the direction toward the base portion A as viewed from the mold portion B, i.e., the direction corresponding to the radially outer side of the tire, will be referred to as the up-down direction, and the direction corresponding to the radially outer side of the tire will be referred to as the up-down direction. Furthermore, the direction along the circumferential direction of the tire will be referred to as the lateral direction.

[0034] Mold portion B is designed by a design method in which a mold (shape) that will be the basic shape of the sipe is determined as cell 1, and the cells 1 are arranged to determine the overall shape of the sipe. Mold portion B can be manufactured by arranging cells 1 to match the desired size (depth and width) of the sipe. Mold portion B and blade 100 equipped with it can be output (constructed) using, for example, a 3D printer. That is, first, the mold of cells 1 is determined, and then the overall shape of mold portion B is designed by arranging them. Then, mold portion B can be manufactured by outputting using a 3D printer to match the designed overall shape.

[0035] In this embodiment, the cell 1 may be formed in a rectangular shape when viewed from the front of the plate surface. FIG. 1 illustrates a case where the cell 1 is square. Alternatively, the cell 1 may have a shape that can be formed into a single plate by arranging cells 1 of the same shape adjacent to each other. One example of another shape that the cell 1 can have is a hexagon.

[0036] The shape of the mold for the cell 1 can take various forms depending on the required specifications for each tire. Specific examples of the shapes of the cell 1 and mold part B according to this embodiment will be described below.

[0037] (First embodiment) 2 and 3 show a cell 2 having a wave-shaped bent shape as an example of the cell 1 according to this embodiment. Fig. 3 is a view of the cell 2 shown in Fig. 2 as seen from the rear side.

[0038] The cell 2 is formed with thick portions 22, 24, and 26 that are thicker than the other portions of the cell 2. The thick portions 22, 24, and 26 are formed as convex portions with vertices (ridgelines). The cell 2 also has a bent portion 21 formed in the vertical direction as a convex portion shaped like a bent plate surface. The bent portion 21 extends from the upper end to the lower end of the cell 2. In other words, the bent portion 21 is continuous from the upper end to the lower end of the cell 2.

[0039] The thick portion 22 is formed to extend along the ridge line of the bent portion 21. The ridge line of the thick portion 22 and the ridge line of the bent portion 21 are aligned. The thick portion 22 extends from the upper end to the lower end of the cell 2. The thick portion 22 extends from the upper end to the lower end of the cell 2. In other words, the thick portion 22 is continuous from the upper end to the lower end of the cell 2 along the ridge line of the bent portion 21.

[0040] The thick portions 24 extend from the upper end to the lower end along the vertical direction at the lateral end portions of the cell 2. In this embodiment, thick portions 24, 24 are formed at both lateral end portions of the cell 2, respectively.

[0041] The thick portions 26 are formed so as to extend from one end to the other end in the lateral direction. In this embodiment, the thick portions 26, 26 are arranged at the upper and lower ends of the cell 2.

[0042] Between the thick portions 22, 24, a thin portion 23 extends in the up-down direction in terms of thickness relative to the thick portions 22, 24. Between the thick portions 26, 26, a thin portion 25 extends in the horizontal direction in terms of thickness relative to the thick portions 26, 26.

[0043] 4 shows a mold section B formed by arranging six cells 2 (two adjacent in the vertical direction and three adjacent in the horizontal direction) adjacent to each other, with the horizontal direction being the longitudinal direction, as an example. When the cells 2 of this embodiment are arranged adjacent to each other, the ridge lines of the thick-walled portions 22 formed along the bent portions 21 of the cells 2, 2 adjacent in the vertical direction are formed so as to extend continuously from the upper end to the lower end of the mold section B. The number of arranged cells 2 is not limited to six, and may be five or less or seven or more.

[0044] In addition, in the mold section B formed by arranging the cells 2, the valleys of the thin-walled portions 23 of the cells 2, 2 adjacent in the vertical direction are formed so as to extend continuously from the upper end to the lower end of the mold section B.

[0045] In addition, in mold section B formed by arranging cells 2, the thick portions 24, 24 formed at the ends of laterally adjacent cells 2, 2 face each other to form an integral bent portion 29 that extends along the vertical direction and extends from the upper end to the lower end of mold section B. The ridge line of bent portion 29 and the ridge line of the opposing thick portions 24, 24 are aligned.

[0046] In addition, in mold part B formed by arranging cells 2, the thick-walled portions 26 of each laterally adjacent cell 2 are formed so as to extend continuously from one end to the other end in the horizontal direction. Similarly, in mold part B, the thin-walled portions 25 of each laterally adjacent cell 2 are formed so as to extend continuously from one end to the other end in the horizontal direction.

[0047] Thus, in mold part B of this embodiment, if a certain cell 2 is designated as a first cell and another cell 2 adjacent to the first cell 2 is designated as a second cell, the ridges of the first cell and the second cell are continuous.

[0048] Each time the tire is demolded from the mold, mold part B is repeatedly subjected to external forces from the sipes of the tire. However, in mold part B of this embodiment, the bent parts 21, 29 are made thick-walled, thereby improving durability as strength, for example, repeated fatigue life, against the external forces applied to mold part B when the tire is demolded.

[0049] Fig. 5 shows the shape of the space Ba that will remain within a sipe formed with mold portion B shown in Fig. 4 when the sipe deforms with the deformation of the tire tread rubber during tire travel and the inner surfaces of the sipe (portions of opposing inner surfaces that are close to each other) come into contact with each other. In other words, Fig. 5 shows the shape of the space Ba that will always be maintained within the sipe when a tire with sipes formed with mold portion B shown in Fig. 4 is travelling.

[0050] In FIG. 5, each cell space 2a is a part of the space within the sipe formed by the cells 2. Space 22a is a space formed by the bent portion 21 of each cell 2, which extends continuously from the upper end to the lower end of mold portion B. Similarly, space 26a is a space formed by the thick portion 26 of each cell 2, which extends continuously from one end to the other end in the left-right direction of mold portion B. Similarly, space 29a is a space formed by the thick portion 24 (bent portion 29 of mold portion B, see FIG. 4). Spaces 22a and 29a are continuous in the up-down direction, extending from the upper end to the lower end of the sipe. Space 26a is continuous in the horizontal direction, extending from one end to the other end of the sipe in the horizontal direction.

[0051] As shown in FIG. 5, sipes formed using cells 2 can have portions (spaces 22a, 26a, 29a) within the sipe grooves that are wider than other portions. As a result, when the sipes deform due to deformation of the tire tread rubber during tire travel, even after the opposing inner surfaces come into contact with each other in the narrow portions of the sipe gaps (gap portions formed corresponding to the thin-walled portions 23, 25 of mold portion B shown in FIG. 4), wide gaps (spaces 22a, 26a, 29a) formed by the thick-walled portions remain within the sipe gaps. This allows water drawn from the road surface to flow through these gaps (spaces 22a, 26a, 29a). Furthermore, the gaps (spaces 22a, 26a, 29a) between the sipe portions formed by adjacent cells 2 in mold portion B are formed as continuous spaces, allowing water drawn from the road surface to flow through these continuous spaces, thereby enabling appropriate water supply and drainage between the sipes and the tread pattern. That is, in the mold portion B of this embodiment, the strength can be improved, and the supply and discharge and drainage performance of the sipes can be improved.

[0052] Second Embodiment 6 shows a cell 3 having a wave-bent shape different from that of the first embodiment as an example of the cell 1 according to this embodiment. In the following description, descriptions of parts that are the same as those of the first embodiment will be omitted as appropriate.

[0053] The cell 3 has thick portions 32, 34, 36, and 38 that are thicker than other portions of the cell 3. The thick portions 32, 34, 36, and 38 are formed as convex portions with vertices (ridgelines). The cell 3 also has bent portions 31, 35, and 75 as convex portions formed by bending the plate surface.

[0054] Bent portion 31 extends continuously from the upper end to the lower end in the vertical direction. Bent portions 35 and 37 extend continuously from one end to the other along the horizontal direction. Bent portion 35 is bent in the opposite direction to bent portion 37. In other words, when bent portion 37 is a convex portion when viewed from the front, bent portion 35 is a concave portion, and bent portion 35 is a convex portion when viewed from the rear.

[0055] The thick portions 32, 36, 38 are formed so as to be continuous with the ridge lines of the bent portions 31, 35, 37, respectively, and to extend in the same range as the ridge lines. The ridge lines of the thick portions 32, 36, 38 and the ridge lines of the bent portions 31, 35, 37 are aligned.

[0056] The thick portions 34 extend from the upper end to the lower end along the vertical direction at the lateral end portions of the cell 2. In this embodiment, the thick portions 34, 34 are formed at both lateral end portions of the cell 2, respectively.

[0057] In the cell 3, portions other than the thick portions 32, 34, 36, and 38 are relatively thin portions, similar to the case of the cell 2 of the first embodiment. A description of each thin portion of the cell 3 will be omitted.

[0058] 7 shows a mold section B formed by arranging six cells 3 adjacent to each other, as an example. When the cells 3 of this embodiment are arranged adjacent to each other, the ridge lines of the thick-walled portions 33 formed along the bent portions 31 of the cells 3, 3 adjacent in the vertical direction extend continuously from the upper end to the lower end of the mold section B. When the cells 3 of this embodiment are arranged adjacent to each other, the ridge lines of the bent portions 35, 37 formed along the bent portions 35, 37 of the cells 3, 3 adjacent in the horizontal direction extend continuously from one end to the other end of the mold section B in the horizontal direction.

[0059] In addition, in mold section B formed by arranging cells 3, the thick portions 34, 34 formed at the ends of laterally adjacent cells 3, 3 face each other to form an integral bent portion 39 that extends along the vertical direction and extends from the upper end to the lower end of mold section B. The ridge line of bent portion 39 and the ridge line of the opposing thick portions 34, 34 are aligned.

[0060] Furthermore, in mold part B formed by arranging cells 3, the thick portions 36 and thick portions 38 of each of the cells 3 adjacent in the horizontal direction are formed so as to extend continuously from one end to the other end in the horizontal direction.

[0061] FIG. 8 shows the shape of the space Ba for the sipe formed by the mold part B shown in FIG.

[0062] In FIG. 8, each cell space 3a is a part of the space within the sipe formed by the cells 3. Space 32a is a space formed by the thick portion 32. Similarly, spaces 36a and 38a are spaces formed by the thick portions 36 and 38. Similarly, space 39a is a space formed by the thick portion 34 (bent portion 39 of mold portion B, see FIG. 7). Spaces 32a and 39a are continuous in the vertical direction, extending from the upper end to the lower end of the sipe. Spaces 36a and 38a are continuous in the horizontal direction, extending from one end to the other end of the sipe in the horizontal direction. As with the first embodiment, mold portion B in this embodiment can also improve the strength and the air supply / discharge and drainage performance of the sipe.

[0063] (Third embodiment) 9 and 10 show a dimple-shaped cell 4 having a different shape from that of the above embodiment as an example of a cell 1 according to this embodiment. FIG. 10 is a view of the cell 4 shown in FIG. 9 as seen from the rear side. As shown in FIGS. 9 and 10, the cell 4 is formed in a hexagonal shape when viewed from the front. Furthermore, the center portion of the cell 4 when viewed from the front is a smooth convex portion 4A (see FIG. 9) that protrudes to one side, and the opposite surface is a concave portion 4B whose center portion when viewed from the front (rear) is smoothly recessed. In the following explanation, explanations of parts that are the same as those in the first embodiment will be omitted as appropriate.

[0064] Six thick portions 42 are formed in the cell 4, and the thickness of the thick portions 42 is relatively thicker than that of other portions of the cell 4. The thick portions 42 are formed as convex portions with vertices (ridgelines). The thick portions 42 protrude from the same side of the plate surface of the cell 4 as the protruding portion 4A. The cell 4 also has six bent portions 41 formed as convex portions formed by bending the plate surface.

[0065] 9, an imaginary line R is shown along the ridge line of the bent portion 41. The ridge line of the bent portion 41 is on the same side as the protruding portion 4A on the plate surface of the cell 4. The ridge line of each bent portion 41 is the edge of the plate surface of the cell 4, and extends from the center of each side of the hexagonal shape of the cell 4 to just before the protruding portion 4A.

[0066] Each thick portion 42 is formed so as to be continuous along the ridge line of each bent portion 41 and extend in the same range as the ridge line. The ridge line of the thick portion 42 and the ridge line of the bent portion 41 are aligned.

[0067] In the cell 4, the portions other than the thick portion 42 are relatively thin portions, similar to the case of the cell 2 of the first embodiment. A description of each thin portion of the cell 4 will be omitted.

[0068] 11 shows a mold part B formed by arranging six cells 4 adjacent to each other in a triangular houndstooth pattern, as an example. When the cells 4 of this embodiment are arranged adjacent to each other, the ridge line of each thick portion 42 is formed so as to be continuous with the ridge line of the thick portion 42 of the adjacent cell 4.

[0069] FIG. 12 shows the shape of the space Ba for the sipe formed by the mold part B shown in FIG.

[0070] In Fig. 12, each cell space 4a is a part of the space within the sipe formed by the cells 4. Space 42a is a space formed by the thick-walled portion 42. Each space 42a is connected in a network-like manner to form space Ba that extends to the upper and lower ends and both lateral ends of the sipe. As in the first embodiment, mold portion B in this embodiment can also improve the strength and the air supply / discharge and drainage performance of the sipe.

[0071] As described above, a method for designing a tire mold, a tire mold, and a method for manufacturing a tire mold can be provided.

[0072] It should be noted that the embodiments disclosed in this specification are merely examples, and the present invention is not limited to these embodiments, and can be modified as appropriate within the scope of the purpose of the present invention. [Industrial Applicability]

[0073] The present invention can be applied to a method for designing a tire mold, a tire mold, and a method for manufacturing a tire mold. [Explanation of symbols]

[0074] 1: Cell (unit cell) 100: Blades (sipe blades, tire molding molds) 2: Cell 21: Bend 22:Thick part 22a: Space 23: Thin section 24:Thick part 25: Thin section 26:Thick part 26a: Space 29: Bend 29a: Space 2a: Cell space 3: Cell 31: Bend 32:Thick part 32a: Space 33:Thick part 34:Thick part 35: Bend 36: Thick wall part 36a: Space 37: Bend 38: Thick wall part 39: Bend 39a: Space 3a: Cell space 4: Cell 41: Bend 42: Thick wall part 42a: Space 4A: Convex part 4B: Recess 4a: Cell space A: Base B: Mold part Ba: Space R: Virtual line

Claims

1. A method for designing a tire mold for molding a tire having sipes formed in the tread, comprising: A mold that is a basic shape for forming the sipe is defined as a unit cell, and only the unit cells of the same shape are arranged adjacent to each other to define the overall shape of the sipe; a thick portion having a thickness greater than that of other portions of the unit cell in a direction along the axial direction of the tire; forming a protrusion on the unit cell, the protrusion being the thick portion; The convex portion is continuously formed, and the thick portion is provided along the ridge line of the convex portion; A method for designing a tire molding mold, comprising: arranging a first cell, which is a first of the unit cells, and a second cell, which is a second of the unit cells adjacent to the first cell, so that the ridge lines of the first cell and the second cell are continuous.

2. 2. The method for designing a tire mold according to claim 1, wherein the unit cell is a square or a regular hexagon when viewed from the front.

3. A tire mold for molding a tire having sipes formed in the tread, Molds having a basic shape for forming the sipe are arranged adjacent to each other as unit cells, Adjacent unit cells all have the same shape, a thick portion having a thickness that is relatively thicker than other portions of the unit cell in a direction along the axial direction of the tire; a protrusion is formed in the unit cell, the protrusion being the thick portion, the protrusion is formed continuously, and the thick portion is provided along the ridge line of the protrusion, A tire molding mold in which a first cell, which is a first unit cell, and a second cell, which is a second unit cell adjacent to the first cell, are arranged so that the ridge lines of the first cell and the second cell are continuous.

4. 4. The tire mold according to claim 3, wherein the unit cells are square or regular hexagonal in front view.

5. A method for manufacturing a tire mold for molding a tire having sipes formed in the tread, comprising: A mold having a basic shape for forming the sipe is used as a unit cell, and only the unit cells having the same shape are arranged adjacent to each other, a thick portion having a thickness greater than that of other portions of the unit cell in a direction along the axial direction of the tire; forming a protrusion on the unit cell, the protrusion being the thick portion; The convex portion is continuously formed, and the thick portion is provided along the ridge line of the convex portion; A method for manufacturing a tire mold, comprising: arranging a first cell, which is a first of the unit cells, and a second cell, which is a second of the unit cells adjacent to the first cell, so that the ridge lines of the first cell and the second cell are continuous.

6. The method for manufacturing a tire mold according to claim 5, wherein the unit cell has a square or regular hexagonal shape when viewed from the front.

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