JP7288386B2 - Tire manufacturing equipment and bead ring - Google Patents

Description

TECHNICAL FIELD The present invention relates to a tire manufacturing apparatus and a bead ring.

The bead ring of Patent Document 1 has a bead bottom forming ring portion having a cavity surface for forming the bead bottom surface of the bead portion of a green tire, and a bead heel forming ring portion having a cavity surface for forming the bead heel surface of the bead portion. and a ring portion.

JP 2016-150540 A

When a tire is vulcanized using the tire vulcanizing mold equipped with the bead ring of Patent Document 1, part of the green tire may be caught between the bladder and the bead bottom forming ring. A pinch may occur at the radially inner end of the bead portion of the tire. The pinch generated in the bead portion is generally cut after vulcanization molding.

SUMMARY OF THE INVENTION An object of the present invention is to provide a tire manufacturing apparatus and a bead ring that can suppress the occurrence of pinching in the bead portion of a tire.

One aspect of the present invention includes a tire vulcanization mold having a bead ring for molding a bead portion of a tire, and a bladder positioned inside the tire vulcanization mold, wherein the bead ring an annular body having a bead forming surface forming a portion; a recess provided in an end face extending radially inward from the bead forming surface; a ring, a biasing member provided between the main body and the movable ring to bias the movable ring in a direction of protruding from the recess, and an elastic member disposed between the main body and the movable ring. The main body defines a part of the recess, is provided contiguously with a radially inner edge of the bead forming surface, and has a first inclined surface inclined with respect to the moving direction of the movable ring. wherein the movable ring has a second inclined surface facing the first inclined surface of the main body and inclined with respect to the movement direction, the first inclined surface of the main body and the movable ring The second inclined surfaces are configured to come close to each other when the movable ring moves along the moving direction so as to retreat into the recess, and the elastic member is the first inclined surface of the main body. Provided is a tire manufacturing apparatus arranged on the bladder side of a gap between an inclined surface and the second inclined surface of the movable ring.

According to the tire manufacturing apparatus of the present invention, the movable ring approaches the main body along the moving direction because the bladder presses the movable ring. At this time, the first inclined surface of the main body and the second inclined surface of the movable ring are close to each other, and the elastic member disposed between the first inclined surface and the second inclined surface is positioned between the first inclined surface and the second inclined surface. It is pressed and deformed by the surface. A portion of the deformed elastic member protrudes toward the bladder, thereby suppressing the green tire from being caught between the bladder and the movable ring. As a result, pinching at the radially inner end of the bead portion of the tire can be suppressed.

Another aspect of the present invention is an annular body having a bead forming surface for forming a bead portion of a tire, a recess provided in an end surface extending radially inward from the bead forming surface, and a bead extending axially from the recess. a movable ring provided to be protrusive and retractable; a biasing member provided between the main body and the movable ring to bias the movable ring in a direction of protruding from the recess; and an elastic member arranged between the movable ring, the main body defining a part of the recess, being connected to the radially inner edge of the bead forming surface, and configured to move the movable ring. The movable ring has a first inclined surface inclined with respect to a direction, the movable ring has a second inclined surface facing the first inclined surface of the body and inclined with respect to the moving direction, The first inclined surface and the second inclined surface of the movable ring are configured to approach each other when the movable ring moves along the movement direction so as to retreat into the recess, The elastic member is arranged near the edge of the bead forming surface in a gap between the first inclined surface of the main body and the second inclined surface of the movable ring. do.

According to the bead ring of the present invention, when a tire is manufactured using this bead ring, pinching at the radially inner end portion of the bead portion of the tire can be suppressed.

ADVANTAGE OF THE INVENTION According to this invention, generation|occurrence|production of the pinch in the bead part of a tire can be suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS Sectional drawing of the tire manufacturing apparatus which concerns on embodiment of this invention. Sectional drawing of the bead ring which concerns on embodiment. FIG. 4 is a schematic cross-sectional view around the bead ring when the movable ring is at the projecting position; FIG. 4 is a schematic cross-sectional view around the bead ring when the movable ring is between the protruded position and the retracted position; FIG. 4 is a schematic cross-sectional view around the bead ring when the movable ring is in the retracted position;

Embodiments of the present invention will now be described with reference to the accompanying drawings.

(overall structure)
FIG. 1 is a cross-sectional view showing a schematic configuration of a tire manufacturing apparatus 1 according to this embodiment, showing only one side in the tire radial direction (the right side in FIG. 1). In FIG. 1, a pneumatic tire T to be vulcanized and molded in the tire manufacturing apparatus 1 is also shown by a virtual line (a two-dot chain line). The pneumatic tire T is manufactured by setting a green tire in the tire manufacturing apparatus 1 so that the tire axis is oriented in the vertical direction, and vulcanizing and molding the green tire.

A tire manufacturing apparatus 1 includes a tire vulcanizing mold 2 for vulcanizing a pneumatic tire T. As shown in FIG.

As shown in FIG. 1, the tire vulcanization mold 2 includes an annular sector mold 3, a pair of upper and lower side plates 4, 4 positioned on the inner diameter side of the sector mold 3, and a pair of upper and lower bead rings positioned further on the inner diameter side. 5, 5, and a cavity 6 in which the pneumatic tire T is vulcanized is defined inside them. The tire vulcanization mold 2 is configured as a so-called segmented mold.

The inner wall surfaces defining the cavity 6 of the sector mold 3, the side plates 4, 4, and the bead rings 5, 5 are formed by vulcanizing the tread portion T1, the sidewall portion T2, and the bead portion T3 of the pneumatic tire T, respectively. It is configured as a molding surface that

The tire manufacturing apparatus 1 also includes a bladder 7 arranged inside the tire vulcanization mold 2 .

The bladder 7 is an annular member made of butyl rubber. In addition, the bladder 7 can be expanded and contracted. A high-temperature and high-pressure vulcanizing medium is introduced into the bladder 7, and the bladder 7 expands toward the tire vulcanizing mold 2, thereby pressing the green tire against the molding surface of the tire vulcanizing mold 2 and heating it. and pressurize.

(bead ring)
FIG. 2 is a cross-sectional view of the bead ring 5 according to the embodiment. The configuration of the bead ring 5 will be described below with reference to FIG.

When the bead ring 5 is attached to the tire manufacturing apparatus 1 (shown in FIG. 1), one axial side (the upper side in FIG. 2) of the bead ring 5 is positioned against the tire vulcanization mold 2 (shown in FIG. 1). facing inward. Therefore, in the following description, "one side in the axial direction" may mean the inner side of the tire vulcanization mold 2 when the bead ring 5 is attached to the tire manufacturing apparatus 1 . That is, in the following description, "one side in the axial direction" may mean the side of the bladder 7 (shown in FIG. 1) when the bead ring 5 is attached to the tire manufacturing apparatus 1 . Similarly, the “other side in the axial direction” may mean the outer side of the tire vulcanization mold 2 when the bead ring 5 is attached to the tire manufacturing apparatus 1 . That is, the “other side in the axial direction” sometimes means the side opposite to the bladder 7 when the bead ring 5 is attached to the tire manufacturing apparatus 1 .

Referring to FIG. 2 , the bead ring 5 of this embodiment includes an annular main body 10 , a recess 20 provided in the main body 10 , and a movable ring 30 protruding and retractable from the recess 20 . The bead ring 5 is provided between the main body 10 and the movable ring 30, and includes a plurality of springs 40 that bias the movable ring 30, and an O-ring 50 that is arranged between the main body 10 and the movable ring 30. Prepare.

The body 10 is annular around the tire axis. The body 10 is constructed from a single piece. The main body 10 includes a bead molding surface 11 for molding a bead portion T3 (shown in FIG. 1) of the pneumatic tire T, and an end surface 12 extending radially inward from the bead molding surface 11 . Further, as clearly shown in FIG. 2, the main body 10 includes a first inclined surface 13 provided continuously with a radially inner edge 11a (indicated by a dot in FIG. 2) of the bead forming surface 11, and a first A first bottom surface 14 provided contiguously with the radially inner end of the inclined surface 13 , and a first side surface 15 provided contiguously with the radially inner end of the first bottom surface 14 .

The bead forming surface 11 and the end surface 12 of the main body 10 are provided on one side (upper side in FIG. 2) of the main body 10 in the axial direction.

The first inclined surface 13 is inclined from the radially outer side toward the radially inner side toward the other axial side (lower side in FIG. 2). The first inclined surface 13 includes a first portion 13a connected to the radially inner side edge 11a of the bead forming surface 11, a second portion 13b connected to the first portion 13a, and a second portion 13b connected to the first portion 13a. and a third portion 13c provided contiguously with 13b.

The first portion 13a of the first inclined surface 13 is provided at its radially outer end so as to be continuous with the radially inner side edge 11a of the bead forming surface 11 . The first portion 13a is inclined toward the other side in the axial direction from the radially outer side to the radially inner side. Thereby, the first portion 13a of the first inclined surface 13 is inclined with respect to the axial direction.

The second portion 13b of the first inclined surface 13 is provided at its radially outer end so as to be continuous with the radially inner end of the first portion 13a. The second portion 13b is inclined to one side in the axial direction from the radially outer side to the radially inner side.

The third portion 13c of the first inclined surface 13 is provided at its radially outer end so as to be continuous with the radially inner end of the second portion 13b. The third portion 13c is inclined toward the other side in the axial direction from the radially outer side to the radially inner side. Thereby, the third portion 13c of the first inclined surface 13 is inclined with respect to the axial direction.

The inclination angle with respect to the radial direction of the first portion 13a is larger than the inclination angle with respect to the radial direction of the third portion 13c. Further, in the present embodiment, the second portion 13b and the third portion 13c are substantially orthogonal.

The main body 10 has a first holding portion 16 provided so as to be recessed in the first inclined surface 13 . The first holding portion 16 has a triangular cross-sectional shape in the cross section shown in FIG. The first holding portion 16 of this embodiment is defined by the first portion 13a and the second portion 13b of the first inclined surface 13 .

The first bottom surface 14 of the present embodiment extends radially inward from the radially inner end of the first inclined surface 13 .

The first side surface 15 of the present embodiment is provided at the other end in the axial direction so as to be continuous with the radially outer end of the first bottom surface 14 . The first side surface 15 is inclined to one side in the axial direction from the radially outer side to the radially inner side. A locking piece 17 projecting toward the movable ring 30 is provided on the first side surface 15 . Further, although not shown, a locking piece having a configuration similar to that of the locking piece 17 is provided on the third portion 13c of the first inclined surface 13 as well.

The recessed portion 20 of the present embodiment is provided on one end surface 12 of the main body 10 in the axial direction. The recess 20 has a groove shape defined by the first inclined surface 13 , the first bottom surface 14 and the first side surface 15 of the main body 10 . As a result, the recess 20 opens to the end surface 12 on one side of the main body 10 in the axial direction. Moreover, the recessed part 20 has a trapezoidal cross-sectional shape in the cross section shown in FIG. Further, the recess 20 is formed over the entire circumference of the main body 10 .

The movable ring 30 is provided so as to be able to protrude and retract from the opening of the recess 20 . Specifically, the movable ring 30 is movable between a protruding position protruding from the recess 20 and a retracted position housed in the recess 20 . The moving direction of the movable ring 30 of this embodiment coincides with the axial direction.

The movable ring 30 has a shape corresponding to the recess 20 . In other words, in the cross section shown in FIG. 2, the movable ring 30 has a trapezoidal cross-sectional shape. The movable ring 30 includes a second inclined surface 31 that is a radially outer end surface, a second bottom surface 32 that is an end surface on the other side in the axial direction, a second side surface 33 that is a radially inner end surface, and a and an upper surface 34 which is an end surface on one side.

The second inclined surface 31 is provided at one end in the axial direction so as to be continuous with the radially outer end of the upper surface 34 . The second inclined surface 31 is inclined from the radially outer side to the radially inner side toward the other axial side (lower side in FIG. 2). Also, the second inclined surface 31 faces the first inclined surface 13 .

The second inclined surface 31 includes a first portion 31a connected to the upper surface 34, a second portion 31b connected to the first portion 31a, and a third portion connected to the second portion 31b. 31c.

The first portion 31 a of the second inclined surface 31 is provided so as to be continuous with the radially outer end of the upper surface 34 . The first portion 31a is inclined toward the other side in the axial direction (downward in FIG. 2) from the radially outer side toward the radially inner side. Thereby, the first portion 31a is inclined with respect to the axial direction.

The second portion 31b of the second inclined surface 31 is provided so as to continue to the radially inner end of the first portion 31a. The second portion 31b of the second inclined surface 31 is inclined toward the other side in the axial direction from the radially inner side toward the radially outer side.

The third portion 31c of the second inclined surface 31 is provided so as to continue to the radially outer end of the second portion 31b. The third portion 31c is inclined toward the other side in the axial direction from the radially outer side toward the radially inner side. Thereby, the third portion 31c is inclined with respect to the axial direction. A third portion 31 c of the second inclined surface 31 extends parallel to the third portion 13 c of the first inclined surface 13 .

The movable ring 30 includes a second holding portion 35 provided so as to be recessed in the second inclined surface 31 . The second holding portion 35 of this embodiment is defined by the first portion 31 a and the second portion 31 b of the second inclined surface 31 .

The second bottom surface 32 extends radially inward from the radially outer end of the second inclined surface 31 . A mounting hole 32 a for mounting the spring 40 is provided in the second bottom surface 32 . Two mounting holes 32a are provided in the cross section shown in FIG.

The second side surface 33 is provided to connect the radially inner end of the second bottom surface 32 and the radially inner end of the upper surface 34 . The second side surface 33 is inclined to one side in the axial direction from the radially outer side to the radially inner side. The second side surface 33 is provided with a locking groove 36 into which the locking piece 17 provided on the main body 10 is inserted. The locking groove 36 includes a first locking surface 36 a that engages with a locking piece 17 provided on the main body 10 to restrict movement of the movable ring 30 to one side in the axial direction, and a It has a second locking surface 36b that engages with the locking piece 17 to restrict the movement of the movable ring 30 to the other side in the axial direction. The locking groove 36 also has a third locking surface 36c that engages with the locking piece 17 provided on the main body 10 to restrict the radially inward movement of the movable ring 30 . The third locking surface 36c extends along the axial direction in the cross section shown in FIG. Further, although not shown, the third portion 31c of the second inclined surface 31 is also formed with an engaging groove having a configuration similar to that of the engaging groove 36. As shown in FIG. A locking groove (not shown) provided in the third portion 31c of the second inclined surface 31 engages with a locking piece (not shown) provided in the third portion 13c of the first inclined surface 13. to restrict the movement of the movable ring 30 to one side and the other side in the axial direction and to the radially outer side.

The upper surface 34 is provided on one side of the movable ring 30 in the axial direction. The upper surface 34 is a pressed surface that is pressed by the bladder 7 (shown in FIG. 1) during vulcanization. The upper surface 34 extends radially.

A spring 40 is provided between the main body 10 and the movable ring 30 . Specifically, the spring 40 is mounted in the mounting hole 32a of the movable ring 30 and sandwiched between the first bottom surface 14 of the main body 10 and the second bottom surface 32 of the movable ring 30 in a contracted state. Thereby, the spring 40 biases the movable ring 30 toward one side in the axial direction. In this embodiment, two springs 40 are provided side by side in the radial direction in the cross section shown in FIG. Moreover, although not shown, the springs 40 are provided at a plurality of positions in the circumferential direction of the bead ring 5 at regular intervals. The spring 40 of this embodiment is an example of a biasing member according to the invention.

The O-ring 50 of this embodiment is an annular member made of butyl rubber. The O-ring 50 is arranged on one side in the axial direction of the gap between the first inclined surface 13 of the main body 10 and the second inclined surface 31 of the movable ring 30 . In other words, when the bead ring 5 is attached to the tire manufacturing apparatus 1 (shown in FIG. 1), the O-ring 50 is located between the first inclined surface 13 of the main body 10 and the second inclined surface 31 of the movable ring 30. of the gap, is arranged on the side of the bladder 7 (shown in FIG. 1). More specifically, the O-ring 50 is formed in the vicinity of the radially inner edge 11a of the bead forming surface 11 in the gap between the first inclined surface 13 of the main body 10 and the second inclined surface 31 of the movable ring 30. are placed in The O-ring 50 is held by the first holding portion 16 of the main body 10 and the second holding portion 35 of the movable ring 30 . The O-ring 50 of this embodiment is an example of an elastic member according to the present invention.

(Behavior of bead ring)
The movable ring 30 of this embodiment is movable between a protruding position protruding from the recess 20 of the main body 10 and a retracted position retracted into the recess 20 . During vulcanization molding, the movable ring 30 is pushed by the bladder 7 to move from the protruded position to the retracted position. The operation of the bead ring 5 during vulcanization molding will be described below with reference to FIGS. 3 to 5. FIG.

FIG. 3 is a schematic cross-sectional view around the bead ring 5 when the movable ring 30 is at the projecting position. Referring to FIG. 3, the protruding position is such that the movable ring 30 is pressed to one side in the axial direction by a spring 40 provided between the main body 10 and the movable ring 30, and the concave portion 20 (shown in FIG. 2) is positioned. This is the position protruding from the opening. When the movable ring 30 is in the protruded position, the locking piece 17 provided on the main body 10 engages with the first locking surface 36a of the locking groove 36 provided on the movable ring 30, thereby 30 is positioned.

Further, when the movable ring 30 is at the projecting position, the main body 10 and the movable ring 30 are separated. Thereby, when the movable ring 30 is at the projecting position, the first inclined surface 13 of the main body 10 and the second inclined surface 31 of the movable ring 30 are separated from each other.

The O-ring 50 is arranged in the gap between the first inclined surface 13 of the main body 10 and the second inclined surface 31 of the movable ring 30 . In addition, the O-ring 50 is prevented from falling to the other axial side (right side in FIG. 3) by the first holding portion 16 provided on the main body 10 and the second holding portion 35 provided on the movable ring 30. held. On the other hand, when the movable ring 30 is at the projecting position, the gap between the first portion 13a of the first inclined surface 13 and the first portion 31a of the second inclined surface 31 narrows toward one side in the axial direction. , the O-ring 50 is difficult to fall off to one side in the axial direction.

Further, when the movable ring 30 is at the projecting position, the locking piece 17 provided on the main body 10 and the third locking surface 36c of the locking groove 36 provided on the movable ring 30 are engaged with each other. The radially inward movement of the movable ring 30 is restricted. As a result, widening of the gap between the first inclined surface 13 of the main body 10 and the second inclined surface 31 of the movable ring 30 is suppressed. It has become.

As shown in FIG. 3, the green tire G is attached to the tire vulcanization mold 2 during vulcanization molding. During vulcanization molding, the upper surface 34 of the movable ring 30 is pressed by the bladder 7 from the state in which the movable ring 30 is at the projecting position shown in FIG. to move.

FIG. 4 is a schematic cross-sectional view around the bead ring 5 when the movable ring 30 is between the protruded position and the retracted position. In FIG. 4, the movable ring 30 is in the process of moving from the extended position to the retracted position.

Referring to FIG. 4 , when the upper surface 34 is pressed by the bladder 7 , the movable ring 30 moves along the movement direction (axial direction) toward the main body 10 against the biasing force of the spring 40 . At this time, since the first inclined surface 13 of the main body 10 and the second inclined surface 31 of the movable ring 30 are inclined with respect to the movement direction, the first inclined surface 13 and the second inclined surface 31 Get close. In other words, the gap between the first inclined surface 13 and the second inclined surface 31 is narrowed.

Therefore, the O-ring 50 arranged in the gap between the first inclined surface 13 and the second inclined surface 31 is pressed by the first inclined surface 13 and the second inclined surface 31 and elastically deformed. The O-ring 50 deforms along the gap between the first inclined surface 13 and the second inclined surface 31 in the cross section shown in FIG. At this time, the first holding portion 16 of the main body 10 holds the O-ring 50 and restricts the movement of the O-ring 50 to one side in the axial direction. protrude to the side. Specifically, the O-ring 50 protrudes toward the bladder 7 from the radially inner edge 11 a of the bead forming surface 11 .

FIG. 5 is a schematic cross-sectional view around the bead ring 5 when the movable ring 30 is in the retracted position. Referring to FIG. 5, the retracted position is where movable ring 30 is housed in recess 20 (shown in FIG. 2). At this time, the upper surface 34 of the movable ring 30 is flush with the end surface 12 of the body 10 . When the movable ring 30 is at the projecting position, the locking piece 17 provided on the main body 10 engages with the second locking surface 36b of the locking groove 36 provided on the movable ring 30, thereby 30 is positioned.

When the movable ring 30 is in the retracted position, part of the first inclined surface 13 of the main body 10 and part of the second inclined surface 31 of the movable ring 30 are in contact. Specifically, the third portion 13c of the first inclined surface 13 and the third portion 31c of the second inclined surface 31 are in contact with each other. On the other hand, the first portion 13 a of the first inclined surface 13 is separated from the second inclined surface 31 , and the first portion 31 a of the second inclined surface 31 is separated from the first inclined surface 13 . Also, when the movable ring 30 is in the retracted position, the first bottom surface 14 of the main body 10 and the second bottom surface 32 of the movable ring 30 are in contact. When the movable ring 30 is in the retracted position, the first side surface 15 of the main body 10 and the second side surface 33 of the movable ring 30 are in contact.

As described above, a gap is formed between the first portion 13a of the first inclined surface 13 and the first portion 31a of the second inclined surface 31 when the movable ring 30 is in the retracted position. An O-ring 50 is arranged in this gap in a deformed state. A portion of the O-ring 50 protrudes toward the bladder 7 side. Specifically, the O-ring 50 protrudes toward the bladder 7 from the radially inner edge 11 a of the bead forming surface 11 . Thereby, the O-ring 50 seals between the bladder 7, the main body 10 and the movable ring 30 when the movable ring 30 is in the retracted position.

According to the tire manufacturing apparatus of this embodiment, the movable ring 30 approaches the main body 10 along the moving direction by the bladder 7 pressing the movable ring 30 . At this time, the first inclined surface 13 of the main body 10 and the second inclined surface 31 of the movable ring 30 are close to each other, and the O-ring 50 arranged between the first inclined surface 13 and the second inclined surface 31 is positioned at the second inclined surface 13 . It is pressed and deformed by the first inclined surface 13 and the second inclined surface 31 . A portion of the deformed O-ring 50 protrudes toward the bladder 7 , thereby suppressing the green tire G from being caught between the bladder 7 and the movable ring 30 . As a result, pinching at the radially inner end of the bead portion T3 of the pneumatic tire T can be suppressed.

According to the bead ring 5 of the present embodiment, when the pneumatic tire T is manufactured using this bead ring 5, it is possible to suppress the occurrence of pinching at the radially inner end portion of the bead portion T3 of the pneumatic tire T. .

As described above, specific embodiments of the present invention have been described, but the present invention is not limited to the above embodiments, and various modifications can be made within the scope of the present invention.

For example, in the embodiment, the biasing member was the spring 40, but is not limited to this and may be other members such as rubber or leaf springs.

Also, for example, in the embodiment, the movement direction of the movable ring 30 coincides with the axial direction, but is not limited to this, and may have an axial component.

1 Tire Manufacturing Apparatus 2 Tire Vulcanizing Mold 3 Sector Mold 4 Side Plate 5 Bead Ring 6 Cavity 7 Bladder 10 Main Body 11 Bead Molding Surface 11a Edge Side 12 End Surface 13 First Inclined Surface 13a First Part 13b Second Part 13c Third Part Part 14 First bottom surface 15 First side surface 16 First holding part 17 Locking piece 20 Recess 30 Movable ring 31 Second inclined surface 31a First part 31b Second part 31c Third part 32 Second bottom surface 32a Mounting hole 33 Second Side surface 34 Upper surface 35 Second holding part 36 Locking groove 36a First locking surface 36b Second locking surface 36c Third locking surface 40 Spring (biasing member)
50 O-ring (elastic member)
T Pneumatic tire T1 Tread part T2 Side wall part T3 Bead part

Claims (2)

A tire vulcanization mold having a bead ring for molding the bead portion of the tire;
a bladder located inside the tire vulcanization mold;
The bead ring is
an annular body having a bead forming surface for forming the bead;
a recess provided in an end surface extending radially inward from the bead forming surface;
a movable ring provided so as to protrude and retract axially from the recess;
a biasing member provided between the main body and the movable ring for biasing the movable ring in a direction of protruding from the recess;
an elastic member disposed between the main body and the movable ring;
The main body defines a part of the recess, has a first inclined surface that is provided contiguously with a radially inner edge of the bead forming surface, and is inclined with respect to the moving direction of the movable ring,
the movable ring has a second inclined surface facing the first inclined surface of the main body and inclined with respect to the moving direction;
The first slanted surface of the main body and the second slanted surface of the movable ring are configured to approach each other when the movable ring moves along the movement direction so as to retreat into the recess. and
The tire manufacturing apparatus, wherein the elastic member is arranged on the bladder side of a gap between the first inclined surface of the main body and the second inclined surface of the movable ring. an annular body having a bead forming surface for forming the bead portion of the tire;
a recess provided in an end surface extending radially inward from the bead forming surface;
a movable ring provided so as to protrude and retract axially from the recess;
a biasing member provided between the main body and the movable ring for biasing the movable ring in a direction of protruding from the recess;
an elastic member disposed between the main body and the movable ring;
The main body defines a part of the recess, has a first inclined surface that is provided contiguously with a radially inner edge of the bead forming surface, and is inclined with respect to the moving direction of the movable ring,
the movable ring has a second inclined surface facing the first inclined surface of the main body and inclined with respect to the moving direction;
The first inclined surface of the main body and the second inclined surface of the movable ring are configured to approach each other when the movable ring moves along the movement direction so as to retreat into the recess. and
The bead ring, wherein the elastic member is arranged in the vicinity of the edge of the bead forming surface in a gap between the first inclined surface of the main body and the second inclined surface of the movable ring.

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