A method for vulcanizing a tire with a tire vulcanization machine having closing force unit for the treatment space of the tire vulcanization machine. The closing force unit having a base plate and at least one linear drive for the displacement and force application of a mold pressure plate, wherein the at least one linear drive is an integral part of the base plate so that a compact and stringent structure of the closing force unit is supported.

In order to improve tire production efficiency, there is provided a conveying apparatus that conveys a tire-accompanied rigid core in a lying-sideways position to a loading position P1, a preheating device for preheating at a preheating position P2, a vulcanizing device for vulcanizing at a vulcanizing position P3, a cooling device for cooling at a cooling position P4, and a transferring device. The transferring device has a turning arm capable of turning horizontally around an axis of turning and movable up and down, and transfers the tire-accompanied rigid core from and to the conveying device, the preheating device, the vulcanizing device, and the cooling device at the positions P1 to P4. The loading position P1, the preheating position P2, the vulcanizing position P3 and the cooling position P4 are arranged on the same circumferential line centered on the axis of turning.

A tire molding die includes sectors separated from one another in a tire circumferential direction, and sipe blades disposed on tread molding surfaces of the sectors, the sipe blades are disposed repeatedly in the tire circumferential direction in a repeating pattern corresponding to a predetermined arrangement pattern, and a near sipe blade that is included in sipe blades disposed in one of the sectors and that is a sipe blade closest to a division position between the sectors is more rigid than an original shape blade corresponding to the sipe blade provided in the repeating pattern differing from the repeating pattern including the near sipe blade at a position identical to a position of the near sipe blade in the repeating pattern including the near sipe blade.

A tire vulcanizer is disclosed that has superior durability and in which mold parting surfaces defined by a sector and side plates are less likely to be worn even after repeated use. The tire vulcanizer includes: the sector that shapes a tread of a tire; paired upper and lower side plates that shape sidewalls of the tire; a segment that is fixed to the sector and causes the sector to move in a tire radial direction; paired upper and lower attachment plates that are respectively fixed to the paired upper and lower side plates; and the mold parting surfaces defined by the sector and the side plates. Mold inner ends of the mold parting surfaces are arranged on the tread, and the mold parting surfaces extend outward in the tire radial direction from the mold inner ends.

The present invention provides a venting device and a tire mold, which relates to a technical field of tire vulcanization process. A venting device provided by the present invention includes a core shaft and a sleeve sleeved over the core shaft, a venting passage is formed between the sleeve and the core shaft, the core shaft includes a shaft body, one end of the shaft body is connected to a shaft head, the other end of the shaft body is connected to a shaft end piece provided with a groove extending through the shaft end piece, and an end of the groove facing away from the shaft head is closed; the shaft end piece is used for axially stopping the shaft body, and the shaft end piece is further used for assembling the sleeve and the core shaft by contracting and springing back. The venting device provided in the present invention relieves the technical problems existed in the prior art that the closing stroke of the core shaft has low accuracy, the core shaft is less robust and susceptible to be broken, and venting passage blockage and rubber burr occurrence can be avoided.

A heavy-duty tire includes a tread portion including a crown land portion, a shoulder land portion with a tread edge and a middle land portion disposed therebetween. In a tire cross-section of a 5% inflated state, the tread portion comprises a surface profile which comprises an inner arc portion having a radius (R1) of curvature with a center located in a tire equatorial plane and an outer arc portion having a radius (R2) of curvature smaller than the radius (R1) of curvature of the inner arc portion and intersecting the inner arc portion at an inflection point (P). The inflection point (P) is located on the middle land portion, wherein a distance (Lp) in the tire axial direction from the tire equatorial plane to the inflection point (P) is in a range of from 0.35 to 0.50 times a tread half-width (Wt).

A vulcanization mold including blades having a distal end side and pullout is performed smoothly without causing any failure and a pneumatic tire. A vulcanization mold in which a blade has a proximal end, a blade distal end side expanded in a thicknesswise direction on the distal end side, and a blade connection portion that connects the proximal end portion and the blade distal end side is a vulcanization mold in which a sweep area is the difference where a cross sectional area of the blade connection is subtracted from an area blade distal end side to a mold surface with a width equal to a maximum width of a thickness of the blade distal end side in a cross sectional shape perpendicular to a tire widthwise direction of the blade is smaller in circumferential end side regions than in a circumferential central side region of the sector mold.

A vulcanization mold in which a blade has a blade proximal end portion, a blade distal end side thick portion expanded in a thicknesswise direction on the distal end side, and a blade connection portion that connects the portions to each other, is a vulcanization mold wherein a sweep area that is the difference where a cross sectional area of the blade connection portion is subtracted from an area from the blade distal end side thick portion to a mold surface with a width equal to a maximum width of a thickness of the blade distal end side thick portion in a cross sectional shape perpendicular to a tire widthwise direction of the blade is smaller at the blades in circumferential end portion side regions than at the blades in a circumferential central portion side region of the sector mold. Further, a pneumatic tire is manufactured using the vulcanization mold.

A vulcanization mold is a mold including blades having a distal end side thick portion and pullout is performed smoothly by the mold without causing any failure, and a pneumatic tire. A vulcanization mold in which a blade or has a blade proximal end portion, a blade distal end side thick portion expanded in a thicknesswise direction on the distal end side, and a blade connection portion that connects the blade proximal end portion and the blade distal end side thick portion to each other is a vulcanization mold in which a blade density that is a number of blades implanted on a sector mold per unit length in a circumferential direction is lower at the blades in circumferential end portion side regions than at the blades in a circumferential central portion side region of the sector mold. Further, a pneumatic tire is manufactured using the vulcanization mold.

A pneumatic tire includes a carcass layer that has a toroidal shape and extends between a pair of bead portions, a sidewall portion, one of the pair of bead portions being provided at an inner end of the sidewall portion in a tire radial direction TR, and a mark formed in an outer surface of the sidewall portion. The mark includes a protruded portion provided in the outer surface of the sidewall portion and recessed inward in a tire width direction, and a mark body defined by the protruded portion. The surface of the mark body coincides with a reference surface corresponding to the outer surface of the sidewall portion.