Pneumatic tire

Abstract

Provided is a pneumatic tire which has a reduced weight, reduced rolling resistance, and improved anti-separation performance, which are achieved while driving stability is maintained satisfactorily. This pneumatic tire is configured in such a manner that two carcass layers including carcass cords are provided across a pair of bead sections, a bead core and a bead filler are disposed in each of the bead sections, and at least two belt layers are disposed on the outer peripheral side of the carcass layers. The pneumatic tire is characterized by being configured in such a manner that both ends of the inner peripheral carcass layer are turned back from the inside to the outside of the tire around the bead cores while the ends of the turned back sections of the inner peripheral carcass layer are disposed between the inner peripheral belt layer and the body of the inner peripheral carcass layer, and also in such a manner that both ends of the outer peripheral carcass layer are disposed on the outside, in the widthwise direction of the tire, of the turned back sections of the inner peripheral carcass layer, are extended to positions which overlap at least the bead fillers, and are terminated at the bead sections without being turned back around the bead cores.

Description

technical field [0001] The present invention relates to a pneumatic tire including a multi-layer carcass ply, and more specifically, to a pneumatic tire capable of reducing the weight and rolling resistance of the tire while maintaining good steering stability, and improving delamination resistance. Background technique [0002] Pneumatic tires employ a reinforced structure in which multiple layers of carcass plies are bridged between a pair of bead portions in order to maintain a high internal pressure. For example, a pneumatic tire having a so-called 2-1F locked carcass structure has been proposed (for example, refer to Patent Document 1): three layers of carcass plies are bridged between a pair of bead portions, and two layers of inner peripheral side carcass plies are provided. The ends are folded back around the bead cores from the inside to the outside of the tire, and both ends of one outer carcass ply are arranged on the outer side in the tire width direction of the ...

AI Technical Summary

Problems solved by technology

[0004] However, pneumatic tires are often exposed to severe usage environments such as a high load state due to overloading and / or a high internal pressure state for ensuring load capacity, so if the end of the carcass ply is often arranged at the bead portion or The parts of the sidewall that are prone to deflection are prone to delamination failures starting from these ends

In addition, in the case where three carcass plies are used, the weight of the tire increases, and thus, there is also a problem that the rolling resistance of the tire increases.

[0005] In addition, the above-mentioned problems can be overcome by reducing the number of layers of the carcass ply, but in this case, the rigidity of the tire as a whole decreases, resulting in a decrease in steering stability.

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