Pneumatic tire and method for manufacturing the same
AssigneeBridgestone Corporation
InventorMasashi HASHIMOTO
Life of this patent
Estimating the term…
Abstract
In a pneumatic tire, respective end portions in the tire circumferential direction of a composite layer of an inner liner and a rubber layer are jointed at a joint portion; the lower inner liner layer has a first edge and the upper inner liner layer has a second edge at the joint portion; the first edge is separated from the upper inner liner layer by the rubber layer; provided that a position on the upper inner liner layer at the same height as the lower inner liner layer and closest to the first edge is “P”, a circumferential distance measured from the first edge to the position P is “L”, and a circumferential distance measured from the second edge to the position P is “T”, T≤35 mm, T−L/2≥9 mm, and 0×T<L≤0.2×T.
Claims20
A pneumatic tire having a carcass layer extending across a pair of bead cores and an inner liner layer formed of a thermoplastic resin and provided on the tire inner surface side of the carcass layer, wherein:
- the inner liner layer and a rubber layer provided on the side facing the carcass layer, of the inner liner layer, form a composite layer in combination;
- respective end portions in the tire circumferential direction of the composite layer are jointed in the tire circumferential direction in an overlapping manner at a joint portion of the composite layer;
- the lower inner liner layer, situated on the lower side or the tire inner surface side of the overlapping end portions of the composite layer, has a “first edge” at the joint portion;
- the upper inner liner layer, situated on the upper side of the overlapping end portions of the composite layer, has a “second edge” at the joint portion;
- the first edge of the lower inner liner layer is separated from the upper inner liner layer by the rubber layer;
- provided that a position in the tire circumferential direction on the upper inner liner layer at the same height in the tire radial direction as the lower inner liner layer, at which position the upper inner liner layer is closest to the first edge of the lower inner liner layer, is “P”, a distance in the tire circumferential direction measured from the first edge to the position P is “L”, and a distance in the tire circumferential direction measured from the second edge to the position P is “T”, T≤35 mm, T−L/2≥9 mm, and 0×T<L≤0.2×T.
A method for manufacturing a pneumatic tire having a carcass layer extending across a pair of bead cores and an inner liner layer formed of a thermoplastic resin and provided on the tire inner surface side of the carcass layer, wherein the inner liner layer and a rubber layer provided on the side facing the carcass layer, of the inner liner layer, form a composite layer in combination, and respective end portions in the tire circumferential direction of the composite layer are jointed in the tire circumferential direction in an overlapping manner at a joint portion, wherein
- when the overlapping end portions of the composite layer at the joint portion is constituted of the lower composite layer situated on the lower side or the tire inner surface side and the upper composite layer situated on the upper side, the method comprises:
- forming an end face of the rubber layer of the lower composite layer to be a slant face slanting from a lower edge of the rubber layer, on the outer side in the tire circumferential direction, toward the outer side in the tire radial direction;
- and
- subjecting the tire to vulcanization in a state where the upper composite layer overlaps with the lower composite layer, to form the joint portion.
Dependencies are inferred from the claim text.