JP2015016609A - Tire vulcanizing mold and tire manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tire vulcanizing mold which can maintain exhaust performance for a long time by preventing malfunction of a vent plug due to rubber biting, and a method for manufacturing a tire using the tire vulcanizing mold.SOLUTION: A vent plug 2 fitted into an exhaust hole 16 opening in a molding surface 1 includes a cylindrical housing 3 having an exhaust passage 21 therein, a stem 4 inserted into the housing 3 and serving as a valve body opening and closing the exhaust passage 21, and an energizing member 5 energizing the stem 4 toward a cavity 15 so as to open the exhaust passage 21. The stem 4 has a columnar trunk part 41 extending in an axial direction of the housing 3, and a head part 42 closing the exhaust passage 21 by being brought into contact with the inner surface of an opening part 31 of the housing 3. A central axis 3A of the housing 3 is inclined with respect to a normal line NL of the molding surface 1 passing through an opening center 16C of the exhaust hole 16.

Description

  The present invention relates to a tire vulcanization mold in which a vent plug is attached to an exhaust hole of a molding surface in contact with an outer surface of a tire, and a tire manufacturing method using the same.

  In a tire vulcanization mold used for tire vulcanization molding, a large number of exhaust holes are provided on the molding surface in contact with the outer surface of the tire so that excess air between the tire and the molding surface is discharged to the outside. ing. Also, vent plugs attached to the exhaust holes are known in order to reduce the formation of rubber protrusions called spews. Patent Documents 1 to 3 disclose vent plugs that are opened when a spring is urged to a stem inserted into a cylindrical housing, and closed when the outer surface of the tire pushes down the stem. Yes.

  By the way, on a part of the molding surface, for example, a portion corresponding to a so-called tread shoulder or sidewall in the vicinity of the grounded end of the tire tread, the outer surface of the unvulcanized tire that is expanded and deformed by the expansion of the bladder is against the molding surface. There is a region that does not push from the normal direction. In that region, the unvulcanized rubber flowing along the molding surface approaches the stem from the side, so that the stem that has not yet been fully pushed down is tilted in the housing and the inlet of the exhaust passage is expanded, and the rubber into the housing The exhaust path may be blocked due to the inflow of water. When such a rubber bite occurs, exhaust is no longer possible and the vent plug fails.

JP-A-2-214616 JP-A-9-141660 JP 2011-1116012 A

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a tire vulcanization mold capable of maintaining exhaust performance for a long time by preventing malfunction of a vent plug due to rubber biting, and manufacturing a tire using the same. It is to provide a method.

  The above object can be achieved by the present invention as described below. That is, a tire vulcanization mold according to the present invention includes a molding surface that is in contact with an outer surface of a tire set in a cavity, and a vent plug that is attached to an exhaust hole that is open on the molding surface. The vent plug includes a cylindrical housing having an exhaust passage therein, a stem that is inserted into the housing and serves as a valve body that opens and closes the exhaust passage, and the stem is opened to open the exhaust passage. And a head that closes the exhaust passage by contacting the inner surface of the opening of the housing with a columnar body extending in the axial direction of the housing, and a biasing member that biases toward the cavity And the central axis of the housing is inclined with respect to the normal line of the molding surface passing through the opening center of the exhaust hole.

  In this mold, since the housing is inclined with respect to the normal line of the molding surface as described above, the unvulcanized rubber flowing along the molding surface is difficult to press against the stem from the side. As a result, the phenomenon that the inlet of the exhaust passage expands due to the tilt of the stem in the housing is suppressed, the malfunction of the vent plug due to the rubber engagement is prevented, and the exhaust performance can be maintained for a long time. In particular, when the head of the stem is tilted in a direction opposite to the flow of unvulcanized rubber, the rubber flowing along the molding surface acts to push down the stem. Can be prevented.

  It is preferable that one outer edge of the housing is recessed from the molding surface and the other outer edge of the housing protrudes from the molding surface when viewed in a cross section cut along a plane including the central axis of the housing. At the location where the outer edge of the housing is depressed from the molding surface, the unvulcanized rubber flows into the depressed portion and acts to send air into the exhaust passage, which is convenient for improving the exhaust performance. Moreover, since the hollow corresponding to the protrusion is formed in the tire surface at the location where the outer edge of the housing protrudes from the molding surface, it is convenient for suppressing deterioration of rolling resistance and noise of the tire.

  In this mold, when viewed in a cross section cut by a plane including the central axis of the housing, both outer edges of the housing protrude from the molding surface, or one outer edge of the housing is the molding surface And the other outer edge of the housing may protrude from the molding surface. When convex portions are formed on the tire surface, rolling resistance and noise tend to be deteriorated due to loss and noise due to local compression deformation, and this tendency is particularly remarkable on the tire contact surface. On the other hand, according to said structure, since the convex part resulting from a vent plug is not formed in the tire surface, the rolling resistance of a tire and the deterioration of noise can be suppressed effectively.

  In this mold, when viewed in a cross section cut by a plane including the central axis of the housing, both outer edges of the housing are recessed from the molding surface, or one outer edge of the housing is the molding It may be recessed from the surface and the other outer edge of the housing may coincide with the molding surface. In this case, the vent plug is entirely recessed from the molding surface, and the unvulcanized rubber flows into the recessed portion and acts to send air into the exhaust passage, which is convenient for improving the exhaust performance.

  In this mold, a structure in which the central axis of the housing is inclined at an angle of 2 to 30 degrees with respect to the normal line of the molding surface passing through the opening center of the exhaust hole is practical. If the inclination angle is less than 2 degrees, the effect of preventing rubber biting tends to be small, and even if the inclination angle exceeds 30 degrees, no further improvement effect is seen. In addition, when the inclination angle exceeds 30 degrees, it becomes difficult to construct the exhaust holes and vent plugs, and the unevenness formed on the tire surface becomes large, so that it is not easy to use.

  It is preferable that the distance between the outer edge of the housing recessed or protruding from the molding surface and the molding surface is 2 mm or less when measured in the axial direction of the housing. Thereby, the unevenness formed on the tire surface due to the vent plug is prevented from becoming too large, and the influence on the tire appearance can be suppressed. Moreover, since the size of the convex portion formed on the tire surface is suppressed, it is convenient for suppressing deterioration of tire rolling resistance and noise.

  It is preferable that the head portion of the stem is formed in a truncated cone shape whose diameter increases toward the cavity, and the inner surface of the opening of the housing is formed by a tapered surface whose diameter increases toward the cavity. According to such a configuration, the relative position of the head portion of the stem with respect to the opening portion of the housing is accurately determined in a state where the exhaust passage is closed.

  In this mold, the top surface of the head of the stem is disposed flush with the top surface of the opening of the housing in a state where the exhaust passage is closed, or the opening of the housing What is recessed with respect to the top surface is preferable. In such a configuration, the protrusion of the stem from the housing is relatively small when the exhaust path is opened. As a result, the phenomenon that the unvulcanized rubber tilts the stem in the housing and the inlet of the exhaust passage expands is suppressed, and the malfunction of the vent plug due to the rubber biting can be effectively prevented.

  The tire manufacturing method according to the present invention includes the steps of setting an unvulcanized tire in the cavity of the tire vulcanization mold described above, and performing vulcanization by applying heat and pressure to the unvulcanized tire. According to such a method, as described above, the malfunction of the vent plug due to the rubber biting can be prevented, the exhaust performance can be improved, and the generation of residual air can be suppressed, so that a good tire appearance can be obtained.

1 is a longitudinal sectional view schematically showing an example of a tire vulcanizing mold according to the present invention. Sectional view of vent plug cut along a plane containing the central axis of the housing Sectional drawing which shows the closed state of the vent plug of FIG. Sectional drawing which shows the vent plug in another embodiment of this invention Sectional drawing which shows the vent plug in another embodiment of this invention Sectional drawing which shows the vent plug in another embodiment of this invention

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a cross section of a tire vulcanization mold 10 along a tire meridian cross section, and FIGS. 2 and 3 show an enlarged main portion thereof.

  As shown in FIG. 1, the tire vulcanization mold 10 includes a molding surface 1 that is in contact with the outer surface of a tire T set in a cavity 15. The molding surface 1 is provided with a large number of exhaust holes 16 for communicating the inside (cavity 15) of the mold 10 with the outside in order to discharge excess air between the tire and the molding surface 1 during vulcanization molding. It has been. As shown in enlarged views in FIGS. 2 and 3, the vent plug 2 is attached to the exhaust hole 16 opened on the molding surface 1. The exhaust hole 16 has a circular opening, and the normal line NL is a normal line of the molding surface 1 passing through the opening center 16C of the exhaust hole 16.

  An example of the material for the molding surface 1 is an aluminum material. This aluminum material is a concept including not only a pure aluminum material but also an aluminum alloy. For example, Al-Cu, Al-Mg, Al-Mg-Si, Al-Zn-Mg, Al-Mn Al-Si system is mentioned. The housing 3 and the stem 4 to be described later are preferably made of stainless steel or a steel material typified by S45C, which may be the same metal or different metals.

  The mold 10 of the present embodiment includes a tread mold part 11 that molds a tread part of a tire, side mold parts 12 and 13 that mold a sidewall part of the tire, and a bead ring 14 into which the bead part of the tire is fitted. With. Although not shown, a convex bone portion for forming a groove in the tread surface of the tire is provided on the inner surface of the tread mold portion 11. In FIG. 1, one exhaust hole 16 opened on the inner surface of the tread mold part 11 and one exhaust hole 16 opened on the inner surface of the side mold part 13 are drawn. A large number of exhaust holes 16 that open on the inner surface of the mold part 12 are provided.

  As shown in FIG. 2, the vent plug 2 includes a cylindrical housing 3 having an exhaust passage 21 therein, a stem 4 that is inserted into the housing 3 and serves as a valve body that opens and closes the exhaust passage 21, and an exhaust passage 21. And a biasing member 5 that biases the stem 4 toward the cavity 15 so as to be opened. The housing 3 fitted in the exhaust hole 16 is fixed to the molding surface 1. A top surface 31 a of the opening 31 of the housing 3 faces the cavity 15. The lower end 32 of the housing 3 is formed with a through hole 32a and an inner collar-shaped support 32b.

  The stem 4 has a columnar body 41 extending in the axial direction of the housing 3 and a head 42 that closes the exhaust passage 21 by contacting the inner surface of the opening 31 of the housing 3. A stopper 43 having a diameter larger than that of the through hole 32 a is formed at the lower end of the body portion 41, so that the stem 4 does not come out of the housing 3. The stopper 43 can pass through the through hole 32a by being elastically deformed so as to close the slit 44. The top surface 31a of the opening 31 and the top surface 42a of the head portion 42 are each formed by a flat surface. The urging member 5 surrounds the cylindrical body portion 41 and is interposed between the head portion 42 and the support portion 32 b to urge the stem 4.

  In FIG. 2, the exhaust path 21 is open, and the vent plug 2 is in an open state. While the vent plug 2 is in the open state, the air in the cavity 15 is discharged to the outside of the mold 10 through the exhaust passage 21 as the outer surface of the tire approaches the molding surface 1. The exhaust passage 21 passes between the opening 31 of the housing 3 and the head portion 42 of the stem 4, between the trunk portion 41 of the stem 4 and the housing 3 surrounded by the biasing member 5, and through the trunk portion 41 of the stem 4. It is formed between the holes 32a. The inlet of the exhaust path 21 opens in a ring shape between the inner surface of the opening 31 and the side surface of the head portion 42. When the stem 4 is pushed down by the outer surface of the tire in contact with the molding surface 1, the inlet of the exhaust passage 21 is closed and closed as shown in FIG. 3, and the vent plug 2 is closed.

  In the mold 10, as shown in FIGS. 2 and 3, the central axis 3 </ b> A of the housing 3 is inclined with respect to the normal line NL of the molding surface 1 passing through the opening center 16 </ b> C of the exhaust hole 16. The housing 3 is fitted along an exhaust hole 16 that is inclined with respect to the normal line NL. According to such a configuration, the unvulcanized rubber flowing along the molding surface 1 is difficult to press against the stem 4 from the side. As a result, the phenomenon that the inlet of the exhaust passage 21 spreads when the stem 4 is tilted in the housing 3 is suppressed, the malfunction of the vent plug 2 due to the rubber engagement is prevented, and the exhaust performance can be maintained for a long time.

  The exhaust hole 16 shown in FIGS. 2 and 3 is included in a portion where the outer surface of the tire is difficult to push in from the normal direction (for example, a portion corresponding to a so-called tread shoulder or sidewall near the ground contact end of the tire tread). An unvulcanized rubber is provided in a region that flows along the molding surface 1 to the right side of the figure. Assuming that, in the vent plug 2, the head portion 42 of the stem 4 is inclined in a direction opposite to the flow of the unvulcanized rubber (that is, the left side in the figure). According to such a configuration, since the unvulcanized rubber flowing along the molding surface 1 acts so as to push down the stem 4, it is possible to effectively prevent the occurrence of rubber biting.

  According to the knowledge of the present inventor, in general vulcanization molding, in the tread, unvulcanized rubber tends to flow from the center in the tire width direction toward both outer sides, and in the sidewall, the tire is from the vicinity of the tire maximum width position. It has been found that unvulcanized rubber tends to flow toward both sides in the radial direction. Furthermore, tires with a flatness ratio of less than 60% have a strong influence of rubber flow at the tread, and tires with a round cross-section with a flatness ratio of more than 60% tend to have a strong influence of rubber flow at the sidewall. I know.

  Therefore, as shown in FIG. 1, in the exhaust hole 16 that opens near the grounded end of the tread, it is preferable to incline the housing 3 toward the center of the tread toward the cavity 15, and in the tire radial direction from the tire maximum width position of the sidewall. In the exhaust hole 16 opened on the inner side, the housing 3 is preferably inclined toward the cavity 15 outward in the tire radial direction. In addition, it is preferable to incline the housing 3 inward in the tire radial direction toward the cavity 15 in an exhaust hole 16 (not shown) that opens on the outer side in the tire radial direction from the tire maximum width position of the sidewall.

  In FIG. 1, the housing 3 is inclined toward the center of the tread toward the cavity 15 in the exhaust hole 16 opened on the inner surface of the tread mold portion 11. In addition, on the inner surface of the side mold portion 13, the housing 3 is inclined toward the cavity 15 toward the outer side in the tire radial direction in the exhaust hole 16 opened on the inner side in the tire radial direction from the maximum tire width position. Although not shown, if the exhaust hole is opened on the outer side in the tire radial direction from the tire maximum width position, it is preferable to incline the housing in the tire radial direction toward the cavity as described above. The same applies to the side mold portion 12.

  As shown in FIGS. 2 and 3, when viewed in a cross section taken along a plane including the central axis 3 </ b> A of the housing 3, one outer edge 33 a of the housing 3 is depressed from the molding surface 1, and the other outer edge 33 b of the housing 3 is molded surface. 1 protrudes. The outer edges 33a and 33b are locations where the outer peripheral surface of the housing 3 and the top surface 31a intersect in the cross section. Even in the state where the stem 4 is pushed down, the rubber does not flow, but there is a minute gap in the opening 31 through which air can pass, so when the unvulcanized rubber flows into the recessed portion around the outer edge 33a, It acts to send air into the exhaust passage 21 and can maintain the exhaust performance for a long time. Moreover, since the hollow corresponding to protrusion of the periphery of the outer edge 33b is formed in the tire surface, it is convenient to suppress the rolling resistance and noise deterioration of the tire.

  In forming a useful minute gap in the opening 31, the inner surface of the opening 31 and the side surface of the head 42 in contact therewith have an arithmetic average roughness Ra of 0.8 μm or more and less than 2.6 μm, respectively. It preferably has a surface roughness. When this is 0.8 μm or more, air easily passes through the minute gap formed at the contact interface between the opening 31 and the head portion 42, and when this is less than 2.6 μm, Inflow of rubber can be prevented appropriately. In order to suppress rubber biting, the arithmetic average roughness Ra is more preferably 1.2 to 1.8 μm. The arithmetic average roughness Ra is defined in JIS B0601: 2001, and the evaluation method and procedure conform to the provisions of JIS B0633: 2001.

  In this mold 10, it is practically preferable that the central axis 3A of the housing 3 is inclined at an angle of 2 to 30 degrees with respect to the normal line NL of the molding surface 1. That is, the inclination angle θ is preferably 2 degrees or more, more preferably 5 degrees or more, and further preferably 10 degrees or more. Further, the inclination angle θ is preferably 30 degrees or less, more preferably 20 degrees or less, and further preferably 15 degrees or less.

  The distance Da between the outer edge 33a of the housing 3 recessed from the molding surface 1 and the molding surface 1 and the distance Db between the outer edge 33b of the housing 3 projecting from the molding surface 1 and the molding surface 1 are each within 2 mm. Preferably, it is less than 2 mm. The distances Da and Db are both measured in the axial direction of the housing 3. The intervals Da and Db are set to 0.3 mm or more, for example.

  The molding surface 1 has a profile (contour) that is curved along the outer surface of the tire. In FIG. 3, the curved profile 1 a that passes through the exhaust holes 16 is drawn with a broken line. In the mold 10, an intersection 45 between the top surface 42 a of the head 42 and the central axis of the stem 4 (coincident with the central axis 3 </ b> A of the housing 3) in a state where the exhaust passage 21 is closed as shown in FIG. 3. The curved surface 1a of the molding surface 1 is disposed on the cavity 15 side. Thereby, the convex part formed on the tire surface due to the vent plug 2 is reduced, which is convenient for suppressing deterioration of rolling resistance and noise of the tire.

  The intersection 45 described above may be disposed on the curved profile 1a, or may be disposed closer to the exhaust hole 16 than the curved profile 1a (see FIG. 5). In the form in which one outer edge 33a is depressed from the molding surface 1 and the other outer edge 33b projects from the molding surface 1 as shown in FIGS. 2 and 3, the distance Dc is preferably within 1 mm. More preferably, it is within 5 mm. The distance Dc is the distance between the intersection 45 measured in the axial direction of the housing 3 and the curved profile 1a.

  In the state where the exhaust passage 21 is opened as shown in FIG. 2, it is preferable that at least a part of the top surface 42a of the head portion 42 of the stem 4 is disposed closer to the exhaust hole 16 than the curved profile 1a. Thereby, the unvulcanized rubber flowing along the molding surface 1 is likely to come into contact with the head 42 of the stem 4 not from the side but from the top surface 42a side, and the unvulcanized rubber acts to push down the stem 4. Since it can promote, it is advantageous in preventing rubber biting.

  In the present embodiment, the head portion 42 of the stem 4 is formed in a truncated cone shape that expands toward the cavity 15, and the inner surface of the opening 31 of the housing 3 is formed by a tapered surface that expands toward the cavity 15. Has been. In a state where the exhaust path 21 is closed, the side surface of the head portion 42 is in surface contact with the inner surface of the opening 31. According to this configuration, the relative position of the head portion 42 of the stem 4 with respect to the opening 31 of the housing 3 is accurately determined.

  In the present embodiment, the top surface 42a of the head portion 42 of the stem 4 is disposed flush with the top surface 31a of the opening 31 of the housing 3 in a state where the exhaust passage 21 is closed. 42a may be recessed with respect to the top surface 31a. In such a configuration, since the protrusion of the stem 4 from the housing 3 is relatively small when the exhaust passage 21 is opened as shown in FIG. 2, it is convenient for preventing malfunction of the vent plug due to rubber engagement. However, it is not restricted to this, The top surface 42a may protrude from the top surface 31a.

  The embodiment shown in FIGS. 4 to 6 has the same configuration as that of the above-described embodiment except for the configuration described below. Therefore, the common points will be omitted and the differences will be mainly described. In addition, the same code | symbol is attached | subjected to the member same as the member demonstrated by the above-mentioned embodiment, and the overlapping description is abbreviate | omitted.

  FIG. 4 is an example in which both outer edges 33 a and 33 b of the housing 3 protrude from the molding surface 1 when viewed in a cross section cut along a plane including the central axis 3 </ b> A of the housing 3. According to such a configuration, since the convex portion due to the vent plug 2 is not formed on the tire surface, it is possible to effectively suppress deterioration of tire rolling resistance and noise. In such a form, the interval Da is, for example, 0 to 0.2 mm, and the interval Db is, for example, 0.3 to 1.3 mm. If the distance Da is 0 mm, one outer edge 33a of the housing 3 matches the molding surface 1, and the other outer edge 33b of the housing 3 projects from the molding surface 1.

  FIG. 5 is an example in which both outer edges 33 a and 33 b of the housing 3 are recessed from the molding surface 1 when viewed in a cross section cut along a plane including the central axis 3 </ b> A of the housing 3. At the time of vulcanization molding, unvulcanized rubber flows into the depression and acts to send air into the exhaust passage 21, which is convenient for improving the exhaust performance. In such a form, the distance Da is, for example, 0.3 to 1.3 mm, and the distance Db is, for example, 0 to 0.2 mm. When the distance Db is 0 mm, one outer edge 33a of the housing 3 is depressed from the molding surface 1, and the other outer edge 33b of the housing 3 is in conformity with the molding surface 1.

  As shown in FIG. 6, also in the vent plug 2 that is attached to a portion that curves in a convex direction toward the cavity 15, the central axis 3 </ b> A of the housing 3 can be inclined with respect to the normal line NL. However, since it is the vent plug 2 attached to a portion that curves in a concave direction toward the cavity 15 as described above, the malfunction due to the rubber bite is likely to occur. It is effective to apply such an inclined structure.

  In the above-described embodiment, the example in which the housing 3 is inclined as described above in the cross section of the mold 10 along the tire meridian cross section has been described. However, the present invention is not limited to this. For example, since the unvulcanized rubber tends to flow toward the bone part at the corner of the bottom of the recess for forming a land part such as a block, the vent plug provided at the corner is from the opening of the housing. The central axis of the housing may be inclined with respect to the normal line of the molding surface so as to approach the bone portion toward the lower end portion.

  The method of manufacturing a tire using the mold 10 includes a step of setting an unvulcanized tire in the cavity 15 of the mold 10 and performing vulcanization by applying heat and pressure to the unvulcanized tire. The tire is expanded and deformed by expansion of a rubber bag called a bladder, and the outer surface of the tire presses against the molding surface 1. In the process, air between the tire and the molding surface 1 is discharged to the outside through the exhaust path 21 of the vent plug 2. At this time, the space in the exhaust hole 16 may be sucked with a suction machine to improve the exhaust performance.

  The tire vulcanization mold described above is the same as an ordinary tire vulcanization mold except that the exhaust hole and the vent plug attached thereto are configured as described above, and has a conventionally known shape, material, mechanism, etc. Any of them can be employed in the present invention.

  The present invention is not limited to the embodiment described above, and various improvements and modifications can be made without departing from the spirit of the present invention. In the above-described embodiment, the mold structure is provided with a tread mold part and a pair of side mold parts, but the present invention is not limited to this. For example, the mold structure is vertically divided into two at the center part of the tread mold part. Also applicable to mold structures. In the above-described embodiment, the urging member is a coil spring, but a disc spring or a leaf spring may be used instead.

DESCRIPTION OF SYMBOLS 1 Molding surface 2 Vent plug 3 Housing 3A Center shaft 4 Stem 5 Energizing member 10 Tire vulcanization mold 15 Cavity 16 Exhaust hole 21 Exhaust path 31 Opening 33a One outer edge 33b The other outer edge 41 The trunk | drum 42 Head

Claims (9)

In a tire vulcanization mold comprising a molding surface in contact with an outer surface of a tire set in a cavity, and a vent plug attached to an exhaust hole opened in the molding surface,
The vent plug includes a cylindrical housing having an exhaust passage therein, a stem that is inserted into the housing and serves as a valve body that opens and closes the exhaust passage, and the stem is inserted into the cavity so as to open the exhaust passage. A biasing member biasing toward the
The stem has a columnar body extending in the axial direction of the housing, and a head that closes the exhaust passage by contacting an inner surface of the opening of the housing,
A tire vulcanization mold, wherein a central axis of the housing is inclined with respect to a normal line of the molding surface passing through an opening center of the exhaust hole.   The one outer edge of the housing is recessed from the molding surface and the other outer edge of the housing protrudes from the molding surface when viewed in a cross section cut along a plane including the central axis of the housing. The tire vulcanization mold described.   When viewed in a cross section cut by a plane including the central axis of the housing, both outer edges of the housing protrude from the molding surface, or one outer edge of the housing matches the molding surface and the The tire vulcanization mold according to claim 1, wherein the other outer edge of the housing protrudes from the molding surface.   Both outer edges of the housing are recessed from the molding surface, or one outer edge of the housing is recessed from the molding surface when viewed in a cross-section cut by a plane including the central axis of the housing; The tire vulcanization mold according to claim 1, wherein the other outer edge of the housing coincides with the molding surface.   The tire vulcanization mold according to any one of claims 1 to 4, wherein a central axis of the housing is inclined at an angle of 2 to 30 degrees with respect to a normal line of the molding surface passing through an opening center of the exhaust hole. .   The tire vulcanized metal according to any one of claims 1 to 5, wherein a distance between an outer edge of the housing that is depressed or protrudes from the molding surface and the molding surface is within 2 mm as measured in an axial direction of the housing. Type.   The head of the stem is formed in a truncated cone shape that expands toward the cavity, and the inner surface of the opening of the housing is formed by a tapered surface that expands toward the cavity. 6. The tire vulcanization mold according to any one of items 6.   In a state where the exhaust passage is closed, the top surface of the head portion of the stem is disposed flush with the top surface of the opening portion of the housing, or with respect to the top surface of the opening portion of the housing. The tire vulcanization mold according to any one of claims 1 to 7, which is recessed.   Manufacturing of a tire including a step of setting an unvulcanized tire in the cavity of the tire vulcanization mold according to any one of claims 1 to 8, and subjecting the unvulcanized tire to heating and pressurizing. Method.

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