Two-Wheeled Vehicle Tire Belt Layer Cord Angle Control
Solution Overview
Problem
Manufacturing a crossed belt for two-wheeled vehicle tires is challenging due to high curvature, which requires difficult angular corrections to avoid overlapping of strip-like elements at the tire shoulder, limiting the ability to select optimal cord angles on the shoulder and crown for desired tire performance.
Innovation Solution
By laying a number of strip-like elements less than a calculated integer N0, which is a function of laying angles, transverse width, and circumferential extension, and controlling the inter-gap between elements, preselected cord angles can be achieved on both the shoulder and crown, independent of tire curvature, ensuring high structural evenness and desired performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If strip-like elements are laid with angular corrections to avoid overlapping at the tire shoulder, then the belt structure avoids overlaps, but the ability to select optimal cord angles on the shoulder and crown is limited
Solution Approach 1:
The invention changes the parameter of the number of strip-like elements from the conventional integer N0 to a reduced integer N, where N < N0. This parameter change allows the belt layer to be formed with fewer elements, enabling preselected cord angles on both shoulder and crown to be achieved independently of tire curvature, while still avoiding overlapping through controlled inter-gap distribution.
2Adaptability or versatility
If the number of strip-like elements is reduced to achieve preselected cord angles, then cord angle selection freedom is improved, but the belt layer may have gaps between elements
Solution Approach 1:
The invention applies local quality by distributing the inter-gap between strip-like elements non-uniformly across the belt layer. The inter-gap is controlled to be larger in certain regions and smaller in others, allowing the overall structure to maintain evenness and stability while accommodating the reduced number of elements and preselected cord angles.
3Manufacturing precision
If angular corrections are applied to avoid overlapping at the shoulder, then overlapping is avoided, but the manufacturing process becomes more complex
Solution Approach 1:
The invention extracts the angular correction requirement from the manufacturing process by reducing the number of strip-like elements to N < N0. This elimination of angular corrections simplifies the manufacturing process while still achieving overlap-free belt layers through controlled inter-gap distribution between the fewer elements.
Data Source
AI summary
A belt structure for a two-wheeled vehicle made by means of strip-like segments or elements, each including parallel cords embedded in an elastomeric layer, sequentially laid along the circumferential extension of a toroidal support so as to form a reinforcing layer having a continuous circumferential extension around a geometric rotation axis of the toroidal support, wherein each strip-like element is laid in a laying trajectory defining, at each point, a laying angle; at each point of the laying trajectory a laying gap is formed between adjacent strip-like elements; the laying trajectory is formed starting from preselected laying angles on the shoulder and on the crown of the tire; the laying gap between adjacent strip-like elements varies along at least one length of said laying trajectory between crown and shoulder so as to cause variation of the laying angle and obtain the preselected angles on the shoulder and on the crown.