Molds and tires

Abstract

To provide tires with excellent wear resistance and low rolling resistance.SOLUTION: A mold 1 for vulcanizing a tire includes a tread ring 2, the tread ring 2 including a tread forming portion 3, a first groove forming protrusion 4 and a second groove forming protrusion 5 that protrude from the tread forming portion 3, and at least one blade 6 whose both ends are connected to the first groove forming protrusion 4 and the second groove forming protrusion 5, and which forms sipes that communicate with two grooves in the tread portion. At least one blade 6 has a main body portion 60 with a thickness of 0.2 mm or less and a reinforcing portion 7 with a thickness greater than 0.2 mm. The reinforcing portion 7 includes a first reinforcing portion 71 formed locally on the side of an inner edge of the blade 6 in the mold radial direction and on the side of a first connection portion 46, which is the connection portion between the blade 6 and the first groove forming protrusion 4.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a mold for vulcanizing and molding a tire. [Background technology]

[0002] BACKGROUND ART Conventionally, a mold including a blade for forming a sipe in a tread portion has been known (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 03-189112 Summary of the Invention [Problem to be solved by the invention]

[0004] Patent Document 1 proposes a blade with a thicker free end. However, because the free end is thickened over the entire length of the blade, the rigidity of the tread portion decreases, wear resistance deteriorates, and rolling resistance increases.

[0005] The present invention has been devised in view of the above circumstances, and has as its main object to provide a tire having good wear resistance and low rolling resistance. [Means for solving the problem]

[0006] The present invention provides A mold for vulcanizing and molding a tire, A tread ring for forming a tread portion is included, The tread ring is a tread molding section for molding the tread surface of the tread section; a first groove forming protrusion and a second groove forming protrusion protruding from the tread molding portion to form two grooves adjacent to the tread portion; at least one blade whose both ends are connected to the first groove forming protrusion and the second groove forming protrusion, and which forms a sipe in the tread portion that communicates with the two grooves, The at least one blade has a main body portion having a thickness of 0.2 mm or less and a reinforcement portion having a thickness greater than 0.2 mm; The reinforcing portion includes a first reinforcing portion formed locally on the side of the inner edge of the blade in the mold radial direction and on the side of a first connection portion which is the connection portion between the blade and the first groove forming convex portion. [Effects of the Invention]

[0007] The mold of the present invention has the above-mentioned configuration, and therefore can provide a tire with good wear resistance and low rolling resistance. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a partially cutaway perspective view showing an embodiment of a mold according to the present invention. [Figure 2] FIG. 2 is a cross-sectional view showing a modified example of the mold of FIG. [Figure 3] FIG. 2 is a perspective view showing another modified example of the mold of FIG. [Figure 4] FIG. 2 is a perspective view showing yet another modified example of the mold of FIG. [Figure 5] FIG. 2 is a perspective view showing yet another modified example of the mold of FIG. [Figure 6] FIG. 6 is a cross-sectional view showing the mold of FIG. 5. [Figure 7] FIG. 2 is a development view showing yet another modified example of the mold of FIG. [Figure 8] FIG. 2 is a perspective view of a tire vulcanized and molded using the mold of FIG. 1. DETAILED DESCRIPTION OF THE INVENTION

[0009] An embodiment of the present invention will now be described with reference to the drawings. FIG. 1 is a cross-sectional view showing the configuration of a mold 1 of this embodiment.

[0010] The mold 1 includes a tread ring 2 for molding the tread portion. The tread ring 2 may be divided in the mold circumferential direction or the mold axial direction. The mold circumferential direction is the direction corresponding to the tire circumferential direction inside the mold. The same applies to the mold axial direction and the mold radial direction.

[0011] The tread ring 2 includes a tread surface forming portion 3 for forming the tread surface of the tread portion, a first groove forming protrusion 4 and a second groove forming protrusion 5 for forming two grooves adjacent to the tread portion, and a blade 6 for forming a sipe in the tread portion.

[0012] The first groove forming protrusion 4 and the second groove forming protrusion 5 are formed by protruding radially inward from the tread surface forming portion 3. The first groove forming protrusion 4 and the second groove forming protrusion 5 are arranged adjacent to each other and facing each other.

[0013] The protrusion height (corresponding to the groove depth) of the first groove forming protrusion 4 and the second groove forming protrusion 5 from the tread molding portion 3 is desirably 12 mm or more. Such a mold 1 is suitable for vulcanization molding of heavy-duty tires.

[0014] In this embodiment, the first groove forming protrusions 4 and the second groove forming protrusions 5 extend in the circumferential direction of the mold. Circumferential grooves extending in the circumferential direction of the tire are formed by such first groove forming protrusions 4 and second groove forming protrusions 5. The first groove forming protrusions 4 and the second groove forming protrusions 5 may also extend in the axial direction of the mold.

[0015] In addition to the first groove forming protrusions 4 and the second groove forming protrusions 5, the tread ring 2 may have other groove forming protrusions formed thereon.

[0016] Both ends of the blade 6 are connected to the first groove forming protrusion 4 and the second groove forming protrusion 5. That is, one end of the blade 6 is connected to the first groove forming protrusion 4, and the other end of the blade 6 is connected to the second groove forming protrusion 5. The first groove forming protrusion 4, the second groove forming protrusion 5, and the blade 6 form two grooves and a sipe connecting the two grooves in the tread portion.

[0017] At least one blade 6 may be provided between the first groove-forming convex portion 4 and the second groove-forming convex portion 5. In a configuration in which the first groove-forming convex portion 4 and the second groove-forming convex portion 5 extend in the circumferential direction of the mold, it is desirable to arrange a plurality of blades 6 at appropriate intervals in the circumferential direction of the mold. Unless otherwise specified, the following description will be given with respect to one blade 6, but it is desirable that the respective features be applied to a plurality of blades 6.

[0018] In this embodiment, the outer end of the blade 6 in the mold radial direction is embedded in the tread surface molding portion 3. In addition, both ends of the blade 6 in the mold axial direction are embedded in the first groove forming convex portion 4 and the second groove forming convex portion 5. This configuration increases the rigidity of the blade 6.

[0019] The protruding height of the blade 6 from the tread forming portion 3 is smaller than the protruding height of the first groove forming protrusion 4 and the second groove forming protrusion 5 from the tread forming portion 3 .

[0020] The blade 6 has a main body portion 60 having a thickness T of 0.2 mm or less, and a reinforcing portion 7 having a thickness T1 greater than 0.2 mm.

[0021] The main body 60 occupies the majority of the blade 6. By setting the thickness T of the main body 60 to 0.2 mm or less, the groove width of the sipe is limited, the reduction in rigidity of the tread portion is suppressed, the wear resistance is improved, and the rolling resistance is reduced.

[0022] The reinforcing portion 7 reinforces the main body portion 60. When the mold 1 is opened and the vulcanized tire is removed from the mold 1, a large stress is generated in the blade 6. If a large stress is generated in the blade 6 having a thickness of 0.2 mm or less, the blade 6 may be deformed. In the mold 1 of the present invention, the main body portion 60 is reinforced by the reinforcing portion 7 having a thickness T1 greater than 0.2 mm, so deformation of the blade 6 is suppressed. Therefore, by setting the thickness T of the main body portion 60 even thinner, it is possible to further improve wear resistance and further reduce rolling resistance.

[0023] The reinforcing portion 7 has a first reinforcing portion 71. The first reinforcing portion 71 is disposed on the side of the first groove forming convex portion 4.

[0024] The first reinforcing portion 71 is disposed on the side of the inner edge 61 in the mold radial direction, which is the free end side of the blade 6. This effectively reinforces the side of the inner edge 61 in the mold radial direction of the blade 6, i.e., the tip side.

[0025] In particular, stress is likely to concentrate at the first connection portion 46, which is the connection portion between the blade 6 and the first groove forming convex portion 4. In the mold 1 of the present invention, the first reinforcing portion 71, which is locally formed on the side of the first connection portion 46, relieves the stress concentration at the first connection portion 46 and suppresses deformation of the blade 6.

[0026] The term "locally formed" means that the first reinforcing portions 71 are not formed over the entire tire from the first groove-forming ridges 4 to the second groove-forming ridges 5, but are formed partially on the side of the first connecting portions 46. Because the first reinforcing portions 71 are formed locally, the decrease in rigidity of the tread portion is limited, improving wear resistance and reducing rolling resistance.

[0027] The shape of the blade 6 may be planar, two-dimensional, extending in a zigzag pattern in one direction, or three-dimensional, extending in a zigzag pattern in two directions. By combining a two-dimensional or three-dimensional blade with the first reinforcing portion 71, the strength of the blade 6 is dramatically improved.

[0028] Fig. 2 shows a mold 1A including a modified example of the reinforcing portion 7 of Fig. 1. For parts of the mold 1A of Fig. 2 that are not described below, the configuration of the mold 1 of Fig. 1 described above can be adopted.

[0029] 2, it is preferable that the reinforcing portion 7 further includes a second reinforcing portion 72 locally formed on the side of the second connecting portion 56, which is the connecting portion with the second groove forming convex portion 5. The first reinforcing portion 71 and the second reinforcing portion 72 reinforce both ends of the blade 6.

[0030] The second reinforcing portion 72 has the same features as the first reinforcing portion 71. That is, the second reinforcing portion 72 is disposed on the side of the inner edge 61 in the mold radial direction, which is the free end side of the blade 6. This effectively reinforces the side of the inner edge 61 in the mold radial direction of the blade 6, i.e., the tip portion.

[0031] In particular, stress is likely to concentrate at the second connection portion 56, which is the connection portion between the blade 6 and the second groove forming convex portion 5. In the mold 1 of the present invention, the second reinforcing portion 72, which is locally formed on the side of the second connection portion 56, relieves the stress concentration at the second connection portion 56 and suppresses deformation of the blade 6.

[0032] Furthermore, since the second reinforcing portions 72 are formed locally, the decrease in rigidity of the tread portion is limited, the wear resistance is improved, and the rolling resistance is reduced.

[0033] Fig. 3 shows a mold 1 including a modified example of the first reinforcing portion 71. For portions of the first reinforcing portion 71 in Fig. 2 that are not described below, the configuration of the first reinforcing portion 71 in Fig. 1 described above can be adopted.

[0034] 3, the first reinforcing portion 71 preferably includes a first portion 71A that extends from the edge 61 of the blade 6 radially outward in the mold direction to the first connecting portion 46. Such first portion 71A firmly connects the blade 6 and the first groove forming protrusion 4, further suppressing deformation of the blade 6.

[0035] Fig. 4 shows a mold 1 including yet another modified example of the first reinforcing portion 71. For portions of the first reinforcing portion 71 in Fig. 4 that are not described below, the configuration of the first reinforcing portion 71 in Figs. 1 and 3 described above may be adopted.

[0036] 4, the first reinforcing portion 71 includes a first portion 71A that extends radially outward from the edge 61 of the blade 6 to the first connecting portion 46. Furthermore, the first portion 71A is preferably rib-shaped. That is, the shape of the first portion 71A protruding from the main body 60 is preferably a part of a cylinder. Such a first portion 71A further suppresses deformation of the blade 6.

[0037] The configuration corresponding to the first portion 71A can also be applied to the second reinforcing portion 72 of the mold 1A shown in Fig. 2. This firmly connects the blade 6 and the second groove forming convex portion 5, further suppressing deformation of the blade 6.

[0038] Fig. 5 shows a mold 1 including yet another modified example of the first reinforcing portion 71. For portions of the first reinforcing portion 71 in Fig. 5 that are not described below, the configuration of the first reinforcing portion 71 in Figs. 1, 3, and 4 described above may be adopted.

[0039] 5, the first reinforcing portion 71 preferably includes a first portion 71A shown in FIG. 4 and a second portion 71B extending radially inward from the first portion 71A. The second portion 71B further suppresses deformation of the blade 6.

[0040] The second portion 71B intersects with the first portion 71A. The first portion 71A and the second portion 71B form a T-shaped first reinforcing portion 71. This allows the first portion 71A and the second portion 71B to function synergistically, enhancing the reinforcing effect of the first reinforcing portion 71. Furthermore, it is desirable that the second portion 71B has a rib shape. This second portion 71B further suppresses deformation of the blade 6.

[0041] Furthermore, it is desirable that the inner end of the second portion 71B in the mold radial direction extends to the connection portion 46A between the first groove forming protrusion 4 and the edge 61 of the blade 6. Such second portion 71B further suppresses deformation of the blade 6. Furthermore, by combining the two-dimensional or three-dimensional blade, the first reinforcing portion 71, and the second portion 71B, the strength of the blade 6 is further dramatically improved.

[0042] The configuration corresponding to the second portion 71B can also be applied to the second reinforcing portion 72 of the mold 1A shown in Fig. 2. This firmly connects the blade 6 and the second groove forming convex portion 5, further suppressing deformation of the blade 6.

[0043] The first portion 71A desirably protrudes on both sides in the thickness direction of the main body 60 of the blade 6. Similarly, the second portion 71B desirably protrudes on both sides in the thickness direction of the main body 60 of the blade 6. Such first portion 71A and second portion 71B suppress deformation of the blade 6 even when the blade 6 receives a force in any direction in the circumferential direction of the mold.

[0044] The thickness TA of the first portion 71A is preferably two to three times the thickness T of the main body 60. Similarly, the thickness TB of the second portion 71B is preferably two to three times the thickness T of the main body 60. When the thicknesses TA and TB are at least twice the thickness T, deformation of the blade 6 is further suppressed. When the thicknesses TA and TB are no more than three times the thickness T, a decrease in rigidity of the tread portion is suppressed, wear resistance is improved, and rolling resistance is reduced.

[0045] The angle θ at which the first portion 71A and the second portion 71B intersect is preferably 80° to 100°. When the angle θ is 80° to 100°, the first portion 71A and the second portion 71B function evenly, and deformation of the blade 6 is further suppressed.

[0046] Figure 6 shows a desirable form of the mold 1 of Figure 5. As shown in Figure 6, the length L1 of the first portion 71A in the mold radial direction is desirably 20% to 50% of the length L2 from the tread molding portion 3 to the edge 61 of the blade 6 in the mold radial direction.

[0047] The length L1 of the first portion 71A is 20% or more of the length L2 of the blade 6, which easily suppresses deformation of the blade 6. The length L1 of the first portion 71A is 50% or less of the length L2 of the blade 6, which suppresses a decrease in rigidity of the tread portion, improves wear resistance, and reduces rolling resistance.

[0048] The length L3 of the first portion 71A in the mold axial direction is preferably 7% to 12% of the length L4 of the edge 61 of the blade 6 in the mold axial direction.

[0049] The length L3 of the first portion 71A is 7% or more of the length L4 of the blade 6, which easily suppresses deformation of the blade 6. The length L3 of the first portion 71A is 12% or less of the length L4 of the blade 6, which suppresses a decrease in rigidity of the tread portion, improves wear resistance, and reduces rolling resistance.

[0050] Figure 7 shows a mold 1B, which is a modified example of the molds 1 and 1A in Figures 1 and 2. For parts of the mold 1B in Figure 7 that are not described below, the configurations shown in Figures 1 to 6 above can be adopted.

[0051] 7, the first groove-forming protrusions 4 and the second groove-forming protrusions 5 extend in a zigzag pattern in the circumferential direction of the mold. One end of at least one blade 6 is connected to the zigzag apex 40 of the first groove-forming protrusion 4, and the other end is connected to the zigzag apex 50 of the second groove-forming protrusion 5. The apex 40 protrudes to one side in the mold axial direction, and the apex 50 protrudes to the other side in the mold axial direction.

[0052] In the blade 6 connected to the zigzag apexes 40, 50 of the first groove-forming protrusion 4 and the second groove-forming protrusion 5, stress tends to concentrate on the edge 61 (see FIG. 1, etc.) near the connection parts 46, 56. In the mold 1B of this embodiment, a first reinforcing part 71 is formed at the connection part 46 of the blade 6, and a second reinforcing part 72 is formed at the connection part 56, so that deformation of the blade 6 is effectively suppressed.

[0053] The mold 1B is provided with at least two lateral groove forming protrusions 8 that connect the first groove forming protrusion 4 and the second groove forming protrusion 5. The lateral groove forming protrusions 8 are formed by protruding from the tread surface forming portion 3.

[0054] The lateral groove forming protrusion 8 is connected to the zigzag apexes 41, 51 of the first groove forming protrusion 4 and the second groove forming protrusion 5. The apex 41 is adjacent to the apex 40, and the apex 51 is adjacent to the apex 50. The apex 41 protrudes to the same other side as the apex 50, and the apex 51 protrudes to the same one side as the apex 40.

[0055] The first groove forming convex portion 4, the second groove forming convex portion 5, and the two lateral groove forming convex portions 8 form a cavity space for forming a hexagonal block.

[0056] FIG. 8 shows a tire 101 vulcanized and molded using the mold 1 shown in FIG.

[0057] The tire 101 has a tread portion 102. The tread portion 102 is formed with first grooves 104, second grooves 105, and sipes 106. The first grooves 104 are formed by first groove forming ridges 4. The second grooves 105 are formed by second groove forming ridges 5. The sipes 106 are formed by blades 6.

[0058] The first groove 104 and the second groove 105 are arranged adjacent to each other and facing each other. The sipe 106 communicates with the first groove 104 and the second groove 105.

[0059] At least one sipe 106 may be provided between the first groove 104 and the second groove 105. In a configuration in which the first groove 104 and the second groove 105 extend in the tire circumferential direction, it is desirable to provide a plurality of sipes 106 at appropriate intervals in the tire circumferential direction. Unless otherwise specified, the following description will be given with respect to one sipe 106, but it is desirable that the respective characteristics be applied to a plurality of sipes 106.

[0060] The sipe 106 has a main body portion 160 having a width of 0.2 mm or less and an expanded portion 107 having a width greater than 0.2 mm. The main body portion 160 is formed by the main body portion 60 of the blade 6. The expanded portion 107 is formed by the reinforcing portion 7 of the blade 6.

[0061] The widths of the main body portion 160 and the widened portion 107 are measured with the tire in its normal state. Here, "normal state" refers to a state in which the tire is mounted on a normal rim, inflated to the normal internal pressure, and no load is applied. Unless otherwise specified, the dimensions of each part of the tire are values measured in this normal state.

[0062] A "genuine rim" is a rim that is defined for each tire by the standard system that includes the standard on which the tire is based. For example, in the case of JATMA, it is called a "standard rim," in the case of TRA, it is called a "design rim," and in the case of ETRTO, it is called a "measuring rim."

[0063] "Normal internal pressure" refers to the air pressure specified for each tire in the standard system, including the standard on which the tire is based. For JATMA, this is the "maximum air pressure," for TRA, this is the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES," and for ETRTO, this is the "INFLATION PRESSURE." If the tire is for a passenger car, the normal internal pressure is, for example, 180 kPa.

[0064] The main body portion 160 occupies the majority of the sipe 106. By making the width of the main body portion 60 0.2 mm or less, a decrease in the rigidity of the tread portion 102 is suppressed, wear resistance is improved, and rolling resistance is reduced. On the other hand, by making the width of the widened portion 107 greater than 0.2 mm, deformation of the blade 6 for forming the sipe 106 is suppressed.

[0065] The widened portion 107 has a first widened portion 171. The first widened portion 171 is disposed on the side of the first groove 104. The first widened portion 171 is formed by the first reinforcing portion 71 of the blade 6.

[0066] The first widened portion 171 is disposed on the groove bottom side of the sipe 106, i.e., on the radially inner edge of the tire. This prevents a decrease in rubber volume in the tread portion 102, improving wear resistance and wet performance at the end of wear.

[0067] Furthermore, since the first widened portion 171 is formed locally on the side of the connecting portion between the sipe 106 and the first groove 104, the decrease in rigidity of the tread portion is limited, the wear resistance is improved, and the rolling resistance is reduced.

[0068] The sipe 106 may have a second widened portion formed by the second reinforcing portion 72 shown in Fig. 2. The sipe 106 may have a first widened portion formed by the first portion 71A and the second portion 71B shown in Figs. 3 and 4.

[0069] The mold 1 and tire 101 of the present invention have been described in detail above, but the present invention is not limited to the specific embodiments described above and can be modified and practiced in various ways.

[0070] [Note] The present invention includes the following aspects.

[0071] [Invention 1] A mold for vulcanizing and molding a tire, A tread ring for forming a tread portion is included, The tread ring is a tread molding section for molding the tread surface of the tread section; a first groove forming protrusion and a second groove forming protrusion protruding from the tread molding portion to form two grooves adjacent to the tread portion; at least one blade whose both ends are connected to the first groove forming protrusion and the second groove forming protrusion, and which forms a sipe in the tread portion that communicates with the two grooves, The at least one blade has a main body portion having a thickness of 0.2 mm or less and a reinforcement portion having a thickness greater than 0.2 mm; the reinforcing portion includes a first reinforcing portion locally formed on the side of an inner edge of the blade in the mold radial direction and on the side of a first connecting portion which is a connecting portion between the blade and the first groove forming convex portion, Mold. [Invention 2] A mold described in present invention 1, wherein the reinforcing portion includes a second reinforcing portion formed locally on the side of the inner edge of the blade in the mold radial direction and on the side of a second connection portion which is the connection portion between the blade and the second groove forming convex portion. [Invention 3] The mold according to invention 1, wherein the first reinforcing portion includes a first portion extending from the edge of the blade radially outward in the mold to the first connecting portion. [Invention 4] A mold according to present invention 3, wherein the first reinforcing portion includes a second portion extending from the first portion inward in the mold radial direction in a direction intersecting with the first portion. [Invention 5] A mold according to invention 4, wherein the inner end of the second portion in the mold radial direction extends to a connection between the first groove forming protrusion and the edge of the blade. [Invention 6] 6. A mold according to claim 4 or 5, wherein the first portion and the second portion are rib-shaped. [Invention 7] 7. A mold according to any one of claims 4 to 6, wherein the first portion and the second portion are protruded on both sides in the thickness direction of the main body portion of the blade. [Invention 8] 8. The mold according to any one of aspects 4 to 7, wherein the thickness of the first portion and the second portion is two to three times the thickness of the main body portion. [Invention 9] The two groove-forming protrusions extend in a zigzag pattern in the circumferential direction of the die, 9. A mold according to any one of claims 1 to 8, wherein both ends of the at least one blade are connected to the zigzag apexes of the two groove-forming protrusions. [Invention 10] A tire having a tread portion, The tread portion is formed with a first groove, a second groove adjacent to the first groove, and a sipe communicating with the first groove and the second groove, The sipe has a main body portion having a width of 0.2 mm or less and a widened portion having a width greater than 0.2 mm, The widened portion has a first widened portion formed locally on the side of an inner edge of the sipe in the tire radial direction and on the side of a communicating portion between the sipe and the first groove. tire. [Explanation of symbols]

[0072] 1: Mold 1A: Mold 1B: Mold 2: Tread ring 3:Tread molding part 4: First groove forming protrusion 5: Second groove forming convex portion 6: Blade 7: Reinforcement 40:Top 41:Top 46: First connection part 46A: Connection part 56: Second connection part 60: Main body 61: Edge 71: First reinforcement part 71A: 1st part 71B :Second part 72: Second reinforcement part 101: Tires 102: Tread section 104: 1st groove 105:Second groove 106: Sipe 107: Widening section 160: Main body 171: First widening section T: Thickness T1: Thickness TA: Thickness TB: Thickness

Claims

1. A mold for vulcanizing and molding a tire, A tread ring for forming a tread portion is included, The tread ring is a tread molding section for molding the tread surface of the tread section; a first groove forming protrusion and a second groove forming protrusion protruding from the tread molding portion to form two grooves adjacent to the tread portion; at least one blade whose opposite ends are connected to the first groove forming protrusion and the second groove forming protrusion, and which forms a sipe in the tread portion that communicates with the two grooves; The at least one blade has a main body portion having a thickness of 0.2 mm or less and a reinforcement portion having a thickness greater than 0.2 mm; the reinforcing portion includes a first reinforcing portion locally formed on a side of an inner edge of the blade in the mold radial direction and on a side of a first connecting portion which is a connecting portion between the blade and the first groove forming convex portion, Mold.

2. The mold according to claim 1, wherein the reinforcing portion includes a second reinforcing portion formed locally on the side of the inner edge of the blade in the mold radial direction and on the side of a second connection portion which is a connection portion between the blade and the second groove forming convex portion.

3. The mold according to claim 1 , wherein the first reinforcing portion includes a first portion extending from the edge of the blade radially outward in the mold to the first connecting portion.

4. The mold according to claim 3 , wherein the first reinforcing portion includes a second portion extending from the first portion inward in the mold radial direction in a direction intersecting with the first portion.

5. The mold according to claim 4 , wherein an inner end of the second portion in the mold radial direction extends to a connection between the first groove forming protrusion and the edge of the blade.

6. The mold according to claim 4 , wherein the first portion and the second portion are rib-shaped.

7. The mold according to claim 4 , wherein the first portion and the second portion are raised on both sides of the main body portion of the blade in a thickness direction.

8. The mold according to claim 4, wherein the thickness of the first portion and the second portion is two to three times the thickness of the main body portion.

9. The two groove-forming protrusions extend in a zigzag pattern in the circumferential direction of the mold, 6. The mold according to claim 1, wherein both ends of the at least one blade are connected to the zigzag apexes of the two groove-forming protrusions.

10. A tire having a tread portion, a first groove, a second groove adjacent to the first groove, and a sipe communicating with the first groove and the second groove; The sipe has a main body portion having a width of 0.2 mm or less and a widened portion having a width greater than 0.2 mm, The widened portion has a first widened portion formed locally on the side of an inner edge of the sipe in the tire radial direction and on the side of a communicating portion between the sipe and the first groove. tire.

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