Pneumatic Tire Bead Core Wire Layer Segmentation

The bead core is divided into multiple wire layers (first, second, and third wire layers) with distinct functions. The first and second wire layers provide structural strength and engagement, while the third wire layer ensures stable pinching by having its turns positioned at the same axial position. This segmentation allows each layer to contribute specifically to either durability or uniformity, resolving the contradiction between these two requirements.

The patent introduces a new dimension of control by positioning the turns of the third wire layer at the same axial position, creating a common tangent that is substantially parallel to the radial direction. This dimensional arrangement ensures stable pinching and prevents disarrangement of wire turns, thereby improving uniformity without compromising the multi-layer structure's durability benefits.

The wire layers are segmented into different functional groups: the first and second wire layers have turns at different axial positions to ensure engagement stability, while the third wire layer is specifically segmented to have all turns at the same axial position. This segmentation allows the third layer to provide stable pinching with a common tangent parallel to the radial direction, while other layers maintain engagement stability.

Different axial position arrangements are applied locally to different wire layers based on their specific functions. The third wire layer locally implements the same axial position arrangement to ensure pinching stability, while other layers implement different axial positions for engagement stability. This local quality differentiation resolves the contradiction by applying the appropriate arrangement where needed.