JP7257269B2 - Tire mold and tire manufacturing method - Google Patents

Description

The present invention relates to tire molds and tires.

Conventionally, for example, a tire mold includes a plurality of blades for forming sipes in a tire and a mold body fixing the plurality of blades. The tire molds for forming the tread portion of the tire are arranged in parallel in the tire circumferential direction and moved in the tire radial direction.

By the way, the inclination angle between the direction in which the blade protrudes from the mold body and the direction in which the tire mold moves differs depending on the position of the blade. Specifically, the inclination angle of the blades arranged at the ends of the mold body is larger than the inclination angle of the blades arranged at the middle part of the mold body. Therefore, for example, after vulcanization of the tire is completed, when the tire mold moves outward in the tire radial direction and the blade is pulled out from the vulcanized tire, the blade at the end is deformed or damaged. easy to do.

Therefore, for example, the height of the blade at the end is lower than the height of the blade at the intermediate portion (for example, Patent Document 1), and the width of the blade at the end is made lower than the width of the blade at the intermediate portion. A narrower configuration (for example, Patent Document 2) is conceivable. However, if the shapes of the blades at the ends and the blades at the intermediate portion are significantly different, the functions of the sipes formed by the respective blades are changed, resulting in deterioration of tire performance.

JP-A-5-24417 JP 2005-193858 A

Therefore, the first problem is to provide a tire mold that suppresses deformation and damage to the blades and suppresses changes in the functions of the sipes formed by the blades.

A second object is to provide a tire in which changes in the function of sipes are suppressed.

The tire mold is a tire mold arranged in parallel in the tire circumferential direction and moved in the tire radial direction, comprising a plurality of blades for forming sipes in the tire, and a mold body fixing the plurality of blades, The plurality of blades includes a first blade arranged at an intermediate portion in the tire circumferential direction of the mold body and a second blade arranged at an end portion of the mold body in the tire circumferential direction, and the second blade comprises a main body projecting from the mold body and a reinforcing part connected to the main body, the body having the same shape as the portion where the first blade projects from the mold body.

Further, in the tire mold, the total volume of the reinforcing portions connected to the outer surface of the main body in the tire circumferential direction is greater than the total volume of the reinforcing portions connected to the inner surface of the main body in the tire circumferential direction. may be large.

Moreover, in the tire mold, the reinforcing portion may be configured to extend in the height direction of the main body portion.

Further, in the tire mold, the second blade includes a base portion connected to a base end portion of the main body portion and embedded in the mold main body, and the reinforcing portion is a height of the main body portion and the base portion. It may be configured to extend in the vertical direction.

Further, in the tire mold, the reinforcing portion may be arranged at the end portion in the width direction of the main body portion.

Also, a tire is manufactured by the tire mold described above.

FIG. 1 is a cross-sectional view of the essential parts of the tire according to the present embodiment, taken along the tire meridional plane. FIG. 2 is a schematic diagram showing the opened state of the tire mold according to the embodiment. FIG. 3 is a plan view of essential parts showing the opened state of the tire mold according to the embodiment. FIG. 4 is a cross-sectional view of the essential parts in the tire meridional plane showing the state of FIG. FIG. 5 is a plan view of essential parts showing a closed state of the tire mold according to the embodiment. FIG. 6 is a cross-sectional view of the essential parts in the tire meridional plane showing the state of FIG. FIG. 7 is a cross-sectional view of the tire mold according to the same embodiment. FIG. 8 is a front view of the first blade according to the same embodiment. FIG. 9 is a plan view of the first blade according to the same embodiment. 10 is a cross-sectional view taken along the line XX of FIG. 8. FIG. FIG. 11 is a front view of a second blade according to the embodiment; FIG. 12 is a plan view of a second blade according to the same embodiment. 13 is a cross-sectional view taken along the line XIII--XIII of FIG. 11. FIG. FIG. 14 is a front view of a second blade according to another embodiment; FIG. 15 is a plan view of a second blade according to the same embodiment. 16 is a cross-sectional view taken along the line XVI--XVI of FIG. 14. FIG.

An embodiment of a tire mold and a tire will be described below with reference to FIGS. 1 to 13. FIG. In addition, in each figure (as well as in FIGS. 14 to 16), the dimensional ratios of the drawings and the actual dimensional ratios do not necessarily match, and the dimensional ratios between the drawings do not necessarily match. do not have.

As shown in FIG. 1 , the tire 10 includes a pair of bead portions 11 having beads, and sidewall portions 12 extending outward from each bead portion 11 in the tire radial direction D2. The tire 10 also includes a tread portion 13 that is connected to the outer end portions of the pair of sidewall portions 12 in the tire radial direction D2.

The tread portion 13 has a tread surface in contact with the road surface on the outer surface in the tire radial direction D2. Although not shown, the tread portion 13 includes a plurality of main grooves and land portions partitioned by the main grooves. with sipes.

In each figure, the first direction D1 is the tire width direction D1 parallel to the tire rotation axis X1 that is the center of rotation of the tire 10, and the second direction D2 is the tire radial direction D2 that is the diameter direction of the tire 10. and the third direction D3 is the tire circumferential direction D3 around the tire rotation axis X1. The tire equatorial plane S1 is a plane that is perpendicular to the tire rotation axis X1 and is located at the center of the tire 10 in the tire width direction D1. is a plane orthogonal to

As shown in FIGS. 2 to 6, the tire mold 4 is provided in the tire vulcanizer 1. As shown in FIG. The directions D1 to D3 in the tire vulcanizer 1 and the tire mold 4 use the directions for the tire 10 molded by the tire vulcanizer 1 (tire width direction D1, tire radial direction D2, tire circumferential direction D3). .

The tire vulcanizer 1 includes a pair of side plates 2 spaced apart in the tire width direction D1 and a plurality of sectors 3 arranged in parallel along the tire circumferential direction D3. The tire vulcanizing apparatus 1 is an apparatus for forming a vulcanized tire 10 (tire after vulcanization) by vulcanizing an unvulcanized tire 10 (tire before vulcanization).

The side plate 2 includes a side mold 2a whose inner portion in the tire width direction D1 is in contact with the sidewall portion 12 of the tire 10 . The side plate 2 also includes a bead mold 2b into which the bead portion 11 of the tire 10 is fitted.

The sector 3 includes a tire mold (hereinafter also referred to as a "tread mold") 4 whose molding surface 4a on the inner peripheral portion (the inner portion in the tire radial direction D2) is in contact with the tread portion 13 of the tire 10, and the tread mold 4 is the tire diameter. and a mold base 3a mounted inside in the direction D2. The tread mold 4 and the mold base 3a move together in the tire radial direction D2.

The pair of side molds 2a, 2a are arranged apart from the tire 10 set inside the tire vulcanizer 1 in the tire width direction D1. In addition, the plurality of tread molds 4 are arranged outside the pair of side molds 2a, 2a in the tire radial direction D2, and are arranged in the tire circumferential direction D3 with respect to the tire 10 set inside the tire vulcanizing device 1. are arranged in a circular fashion along the

One side mold 2a can move in the tire width direction D1 with respect to the other side mold 2a, and the plurality of tread molds 4 can move in the tire radial direction D2 with respect to the side mold 2a. It is possible. As a result, the tire vulcanizer 1 is switched between a mold open state as shown in FIGS. 2 to 4 and a mold closed state as shown in FIGS.

In the tire vulcanizing apparatus 1, when the mold is opened, the side mold 2a and the tread mold 4 are separated, so that the tire 10 can be put in and taken out. Further, in the tire vulcanizing apparatus 1, since the side mold 2a and the tread mold 4 are in pressure contact when the mold is closed, a closed space (cabinet) for molding the tire 10 is formed inside. .

As shown in FIG. 7, the tread mold 4 includes a mold body 4b having a molding surface 4a, a plurality of blades 5 and 6 for forming sipes in the tire 10, and a plurality of blades for forming grooves in the tire 10. and a convex portion 4c. A plurality of blades 5 and 6 and projections 4c are fixed to molding surface 4a of mold body 4b.

The mold body 4b includes end portions 4d, 4d in the tire circumferential direction D3, and an intermediate portion 4e arranged between the pair of end portions 4d, 4d. The region of the end portion 4d is not particularly limited, but the end portion 4d can be, for example, a region of 20% of the length of the tread mold 4 in the tire circumferential direction D3. 4, 10% of the length in the tire circumferential direction D3.

The plurality of blades 5, 6 includes a first blade 5 arranged at the intermediate portion 4e of the mold body 4b and a second blade 6 arranged at the end portion 4d of the mold body 4b. In FIG. 7, only the first and second blades 5 and 6 are provided. good.

As shown in FIGS. 8 to 10, the first blade 5 is connected to a first body portion 5a projecting from the mold body 4b and a base end portion of the first body portion 5a, and is embedded in the mold body 4b. 1 base portion 5b. And the 1st blade 5 is formed in flat plate shape. That is, the first body portion 5a and the first base portion 5b are each formed in a flat plate shape.

As shown in FIGS. 11 to 13, the second blade 6 is connected to a second body portion 6a projecting from the mold body 4b and a base end portion of the second body portion 6a, and is embedded in the mold body 4b. 2 base portion 6b. The second blade 6 also includes a reinforcing portion 6c connected to the second body portion 6a and the second base portion 6b.

The second body portion 6a is formed in a flat plate shape. Specifically, the second body portion 6a has the same shape as the first body portion 5a. In this specification, the term “same shape” includes errors due to manufacturing errors, etc., for example, different shapes in the range of ± 1 mm in height, different shapes in the range of ± 1 mm in width, thickness includes different shapes in the range of ±0.5 mm.

The second base portion 6b is formed in a flat plate shape. The shape of the second base portion 6b is not particularly limited, but in the present embodiment, the second base portion 6b has the same shape as the first base portion 5b.

The reinforcement portion 6c includes a body reinforcement portion 6d connected to the second body portion 6a and a base reinforcement portion 6e connected to the second base portion 6b. The body reinforcement portion 6d is exposed from the mold body 4b, and the base reinforcement portion 6e is embedded in the mold body 4b.

By the way, if the shapes of the first blade 5 and the second blade 6 are significantly different, the function of the sipe formed by the first and second blades 5 and 6 is changed, so the performance of the tire 10 is degraded. For example, if there is a difference in rigidity of the tire 10 due to a difference in the shape of the sipes, uneven wear occurs, and the wear resistance performance of the tire 10 is reduced.

Therefore, for example, the total volume of the main body reinforcing portion 6d is preferably 50% or less of the total volume of the second main body portion 6a, and more preferably 30% or less of the total volume of the second main body portion 6a. preferable. Thereby, it is possible to suppress a change in the function of the sipes formed by the first and second blades 5 and 6 . The total volume of the main body reinforcing portion 6d with respect to the total volume of the second main body portion 6a is not particularly limited.

Moreover, before vulcanization of the tire 10 is started, the tread mold 4 moves inward in the tire radial direction D2, and the blades 5 and 6 are inserted into the tire 10 before vulcanization. At this time, a first force F1 directed inward in the tire circumferential direction D3 (see FIG. 7) acts on the second blade 6 .

On the other hand, after vulcanization of the tire 10 is completed, the tread mold 4 moves outward in the tire radial direction D2, and the blades 5 and 6 are pulled out from the tire 10 after vulcanization. At this time, a second force F2 directed outward in the tire circumferential direction D3 (see FIG. 7) acts on the second blade 6 . Moreover, since the tire 10 after vulcanization is hardened from the tire 10 before vulcanization, the second force F2 is greater than the first force F1.

Therefore, the total volume of the reinforcing portion 6c connected to the outer side surface 6f of the second main body portion 6a in the tire circumferential direction D3 is equal to the total volume of the reinforcing portion 6c connected to the inner side surface 6g of the second main body portion 6a in the tire circumferential direction D3. larger than the total volume. Specifically, the total volume of the main body reinforcing portion 6d connected to the outer side surface 6f of the second main body portion 6a is larger than the total volume of the main body reinforcing portion 6d connected to the inner side surface 6g of the second main body portion 6a. It's getting bigger.

As a result, the total volume of the reinforcing portion 6c corresponding to the second force F2 is increased, so that the reinforcing portion 6c is arranged so as to effectively reinforce the large second force F2. In this embodiment, the reinforcing portion 6c is connected only to the outer side surface 6f of the second main body portion 6a, and is not connected to the inner side surface 6g of the second main body portion 6a.

Moreover, the cross-sectional shape of the second blade 6 in the direction perpendicular to the height direction is the same throughout the height direction. That is, the cross-sectional shapes of the second main body portion 6a and the main body reinforcement portion 6d are the same in the height direction. As a result, when the tread mold 4 moves outward in the tire radial direction D2 and the blades 5 and 6 are pulled out from the vulcanized tire 10, the reinforcing portion 6c is prevented from being caught on the tire 10. can.

By the way, the second blade 6 tends to be curved or bent in the thickness direction. Therefore, the reinforcing portion 6c extends in the height direction of the second body portion 6a. As a result, since the second main body portion 6a can be reinforced in the height direction, it is possible to suppress the second blade 6 from curving or bending in the thickness direction.

Moreover, the second main body portion 6a is easily deformed at the base end portion in the height direction (specifically, the connection portion with the second base portion 6b). Therefore, the reinforcing portion 6c extends in the height direction of the second body portion 6a and the second base portion 6b. Specifically, the body reinforcing portion 6d is connected to the base reinforcing portion 6e. Thereby, it is possible to suppress deformation of the second main body portion 6a at the base end portion.

Further, the second main body portion 6a is easily deformed even at the ends in the width direction. Therefore, the reinforcing portions 6c are arranged at the widthwise end portions of the second main body portion 6a. Thereby, it is possible to suppress the deformation of the second main body portion 6a at the end portion in the width direction.

The dimensions of the first and second blades 5 and 6 are not particularly limited, but the height of the main body portions 5a and 6a can be, for example, 5 mm to 15 mm, and the thickness can be, for example, 0.3 mm to 2.0 mm. Although the thickness of the reinforcement portion 6c is not particularly limited, it is preferably equal to or less than the thickness of the second main body portion 6a, for example.

As described above, the tire mold 4 according to the present embodiment is arranged in parallel in the tire circumferential direction D3 and moves in the tire radial direction D2. and a mold body 4b for fixing the plurality of blades 5 and 6, wherein the plurality of blades 5 and 6 are a first blade 5 arranged at an intermediate portion 4e of the mold body 4b in the tire circumferential direction D3. , and a second blade 6 disposed at an end portion 4d of the mold body 4b in the tire circumferential direction D3, the second blade 6 comprising a body portion 6a protruding from the mold body 4b, and the body portion 6a and a reinforcing portion 6c connected to the mold body 4b.

According to such a configuration, since the reinforcing portion 6c is connected to the main body portion 6a, the main body portion 6a can be reinforced. The body portion 6a has the same shape as the portion 5a where the first blade 5 protrudes from the mold body 4b. Thereby, while suppressing deformation/damage of the second blade 6, it is suppressed that the function of the sipe formed by each of the blades 5 and 6 is changed. The tire 10 manufactured by the tire mold 4 according to the present embodiment is a tire 10 in which changes in sipe function are suppressed.

Further, in the tire mold 4 according to the present embodiment, the total volume of the reinforcing portion 6c connected to the outer side surface 6f of the main body portion 6a in the tire circumferential direction D3 is It is configured such that it is larger than the total volume of the reinforcing portion 6c connected to the side surface 6g.

According to such a configuration, when the blades 5 and 6 are pulled out from the vulcanized tire 10, the second blade 6 is subjected to a large outward force F2 in the tire circumferential direction D3. The total volume of the reinforcing portion 6c connected to the outer surface 6f of the portion 6a is large. Thereby, the reinforcing portion 6c can effectively reinforce the main body portion 6a.

Further, in the tire mold 4 according to the present embodiment, the reinforcing portion 6c is configured to extend in the height direction of the main body portion 6a.

According to such a configuration, the main body portion 6a tends to bend or bend in the thickness direction, whereas the reinforcing portion 6c extends in the height direction of the main body portion 6a. As a result, since the main body portion 6a can be reinforced in the height direction, it is possible to suppress the main body portion 6a from curving or bending in the thickness direction.

Further, in the tire mold 4 according to this embodiment, the second blade 6 includes a base portion 6b connected to the base end portion of the main body portion 6a and embedded in the mold main body 4b. extends in the height direction of the main body portion 6a and the base portion 6b.

According to such a configuration, the reinforcing portion 6c extends in the height direction of the main body portion 6a and the base portion 6b, while the main body portion 6a is easily deformed at the base end portion. Thereby, it is possible to suppress deformation of the base end portion of the main body portion 6a.

Further, in the tire mold 4 according to the present embodiment, the reinforcing portion 6c is arranged at the end portion in the width direction of the main body portion 6a.

According to such a configuration, the reinforcing portion 6c is arranged at the widthwise end of the main body 6a, while the main body 6a is easily deformed at the widthwise end. Thereby, it is possible to suppress the deformation of the main body portion 6a at the end portion in the width direction.

In addition, the tire mold 4 and the tire 10 are not limited to the configuration of the embodiment described above, and are not limited to the effects described above. Moreover, the tire mold 4 and the tire 10 can of course be modified in various ways without departing from the gist of the present invention. For example, it is of course possible to arbitrarily select one or a plurality of configurations, methods, etc., according to various modified examples described below and employ them in the configurations, methods, etc., according to the above-described embodiment.

(1) In the tire mold 4 according to the above-described embodiment, the body portions 5a and 6a are formed in a flat plate shape. However, the tire mold 4 is not limited to such a configuration. For example, the body portions 5a and 6a may be formed in a plate shape having bent portions and curved portions. That is, the body portions 5a and 6a may have a shape having a constant (same or substantially the same) thickness.

(2) In the tire mold 4 according to the above embodiment, the total volume of the reinforcing portion 6c connected to the outer side surface 6f of the second body portion 6a is connected to the inner side surface 6g of the second body portion 6a. It is configured such that it is larger than the total volume of the reinforcing portion 6c. However, although the tire mold 4 preferably has such a configuration, it is not limited to such a configuration. For example, the total volume of the reinforcing portions 6c connected to the outer side surface 6f of the second main body portion 6a may be less than or equal to the total volume of the reinforcing portions 6c connected to the inner side surface 6g of the second main body portion 6a. .

(3) In addition, in the tire mold 4 according to the above embodiment, the reinforcing portion 6c is connected only to the outer side surface 6f of the second body portion 6a, and is connected to the inner side surface 6g of the second body portion 6a. It is a configuration that does not exist. However, the tire mold 4 is not limited to such a configuration.

For example, the reinforcing portion 6c may be configured to be connected to both the outer side surface 6f and the inner side surface 6g of the second body portion 6a. Further, for example, the reinforcing portion 6c may be connected only to the inner side surface 6g of the second main body portion 6a and not connected to the outer side surface 6f of the second main body portion 6a.

(4) In addition, in the tire mold 4 according to the above-described embodiment, the reinforcing portion 6c is configured to extend in the height direction of the second main body portion 6a. However, although the tire mold 4 preferably has such a configuration, it is not limited to such a configuration. For example, the reinforcing portion 6c may be arranged in a part of the second body portion 6a in the height direction.

(5) In addition, in the tire mold 4 according to the above embodiment, the reinforcing portion 6c is configured to extend in the height direction of the second main body portion 6a and the second base portion 6b. However, although the tire mold 4 preferably has such a configuration, it is not limited to such a configuration. For example, the reinforcing portion 6c may be configured not to be connected to the second base portion 6b. Further, for example, the body reinforcing portion 6d may be configured to be separated from the base reinforcing portion 6e.

(6) In addition, in the tire mold 4 according to the above-described embodiment, the reinforcing portion 6c is arranged at the end portion in the width direction of the second main body portion 6a. However, although the tire mold 4 preferably has such a configuration, it is not limited to such a configuration. For example, the reinforcing portion 6c may be arranged away from the end portion in the width direction of the second body portion 6a.

(7) In addition, in the tire mold 4 according to the above embodiment, the cross-sectional shapes of the second main body portion 6a and the reinforcing portion 6c (main body reinforcing portion 6d) are the same in the height direction. is. However, the tire mold 4 is not limited to such a configuration.

For example, the cross-sectional shape of the reinforcing portion 6c (body reinforcing portion 6d) may be configured such that it becomes thicker from the distal end portion toward the proximal end portion of the second main body portion 6a. Also in such a configuration, when the tread mold 4 moves outward in the tire radial direction D2 and the blades 5 and 6 are pulled out from the vulcanized tire 10, the reinforcing portion 6c is prevented from being caught on the tire 10. can do. For example, the cross-sectional shape of the reinforcing portion 6c (main body reinforcing portion 6d) may be configured such that it becomes thinner from the distal end portion toward the proximal end portion of the second main body portion 6a.

(8) In the tire mold 4, as shown in FIGS. 14 to 16, the reinforcing portions 6c are arranged at the widthwise end and the heightwise tip of the second main body portion 6a. The configuration may be such that That is, the reinforcing portion 6c may be arranged along the outer edge of the second body portion 6a.

According to such a configuration, the second main body portion 6a is easily deformed at the ends in the width direction and the front ends in the height direction, that is, at the outer edges. is arranged over the outer edge of the As a result, deformation of the outer edge of the second body portion 6a can be suppressed.

DESCRIPTION OF SYMBOLS 1... Tire vulcanizer, 2... Side plate, 2a... Side mold, 2b... Bead mold, 3... Sector, 3a... Mold base, 4... Tire mold (tread mold), 4a... Molding surface, 4b... Mold body, 4c... Convex part 4d... End part 4e... Intermediate part 5... First blade 5a... First body part 5b... First base part 6... Second blade 6a... Second body part 6b... Second base portion 6c Reinforcement portion 6d Main body reinforcement portion 6e Base reinforcement portion 6f Outer surface 6g Inner surface 10 Tire 11 Bead portion 12 Sidewall portion 13 Tread D1...Tire width direction D2...Tire radial direction D3...Tire circumferential direction S1...Tire equatorial plane X1...Tire rotation axis

Claims (5)

In the tire mold arranged in parallel in the tire circumferential direction and moved in the tire radial direction,
a plurality of blades for forming sipes in the tire;
a mold body that fixes the plurality of blades,
The plurality of blades includes a first blade arranged at an intermediate portion in the tire circumferential direction of the mold body and a second blade arranged at an end portion of the mold body in the tire circumferential direction,
the second blade includes a body portion projecting from the mold body and a reinforcing portion connected to the body portion,
The body portion has the same shape as the portion where the first blade protrudes from the mold body,
The tire mold, wherein the total volume of the reinforcing portions connected to the outer side surface of the main body portion in the tire circumferential direction is larger than the total volume of the reinforcing portions connected to the inner side surface of the main body portion in the tire circumferential direction. 2. The tire mold according to claim 1 , wherein said reinforcement portion extends in the height direction of said body portion. the second blade includes a base portion connected to the base end portion of the body portion and embedded in the mold body;
3. The tire mold according to claim 2 , wherein the reinforcement portion extends in the height direction of the body portion and the base portion. The tire mold according to any one of claims 1 to 3 , wherein the reinforcing portion is arranged at an end portion in the width direction of the main body portion. A tire manufacturing method comprising a step of vulcanizing an unvulcanized tire with the tire mold according to any one of claims 1 to 4 .

Images