**PNEUMATIC TIRE**

PURPOSE: To make it possible to reduce the weight of a bead while maintaining a required degree of bead strength, by setting the number of effective wires in the section of a bead wire, so that the bead wire becomes as strong as desired, in response to the value of stress generated in the bead wire, including safety factor.

CONSTITUTION: The number n of effective wires in the section of a bead wire 5 is set, so that the strength of the bead wire 5 to the value T of stress generated in the bead wire 5, including the safety factor, satisfies the equation of 1.2T≥Ts.n≥T. In this equation, T=2.5P(Rc2-R2)1Rc is the outermost radius of carcass ply of a tire, R is the radius of the tire at the maximum width position, P is the maximum air pressure set in the range of under 12PR, Ts is the breaking load of one wire, and n is the number of the wires left by subtracting the number of the wires which do not contribute to the breaking strength from the actual sectional number of the wires.

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**B60C15/00***;*

**B60C15/04***; (IPC1-7): B60C15/04; B60C15/00; B60C15/06*

**B60C15/06**