Pneumatic Tire Bead Assembly for Uniform Carcass Ply Length
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for manufacturing pneumatic tires with high uniformity requirements, especially when using carcass plies with high stiffness, result in increased reject rates and complex processes, leading to higher cycle times and reduced cost-effectiveness due to significant length variations between the inner liner and carcass ply at the bead cores.
Innovation Solution
A method involving the use of finger plates to equalize the distance between the inner layer and carcass ply on a tire building drum by smoothing the shoulder area, followed by fixing the bead core with a radially movable core fixation, ensuring minimal length variations before tire formation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If standardized processes are used with carcass plies of higher stiffness, then manufacturing simplicity is maintained, but length variations between inner liner and carcass ply increase leading to higher reject rates
Solution Approach 1:
The invention applies preliminary action by equalizing the distance between the inner liner and carcass ply to the drum shoulder before the bead core is attached. This pre-adjustment ensures that when the bead core is subsequently mounted, the length variations between different bead core positions are minimized, thereby reducing reject rates without complicating the manufacturing process
Solution Approach 2:
The invention changes the parameter of distance uniformity by actively adjusting and equalizing the gap between the inner liner and carcass ply against the drum shoulder. This parameter adjustment compensates for variations introduced by high-stiffness carcass plies, achieving better length uniformity while maintaining manufacturing simplicity
2Manufacturing precision
If complex methods are used to reduce length variations, then manufacturing precision improves, but device complexity and cycle time increase reducing cost-effectiveness
Solution Approach 1:
By performing the distance equalization before bead core attachment, the invention achieves precision improvement with minimal additional complexity. The preliminary adjustment prevents the need for complex post-attachment corrections, maintaining cost-effectiveness
Solution Approach 2:
The invention focuses on changing a single critical parameter (distance to drum shoulder) rather than implementing multiple complex adjustments. This targeted parameter change achieves the desired precision improvement without proportionally increasing device or process complexity
3Manufacturing precision
If complex methods are used to reduce length variations, then manufacturing precision improves, but cycle time increases reducing productivity
Solution Approach 1:
The distance equalization is performed as a preliminary step before bead core attachment, integrating smoothly into the existing workflow. This timing allows the precision improvement to be achieved without creating bottlenecks that would extend the overall cycle time
Solution Approach 2:
By changing the distance parameter through a straightforward adjustment process rather than complex multi-step procedures, the invention achieves precision improvement with minimal impact on cycle time, thereby maintaining productivity
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach reduces length variations between bead cores, enhancing tire uniformity and maintaining cycle time, thereby improving manufacturing efficiency and reducing reject rates.
Implementation Method 1
forming a tire blank by filling a bellows
Implementation Method 2
smoothing the shoulder area of the carcass ply with finger plates
Data Source
Figure 1~2
Figure 3~4
AI summary
The invention relates to a method for manufacturing a pneumatic tire comprising an inner layer (6), a carcass ply (7), a bead core (11), a tire belt, and a tread, comprising the following steps: a) placing the inner layer (6) and the carcass ply (7) onto a tire building drum (1) and onto a support ring (2) with bellows (3), b) forming tire shoulders by expanding the tire building drum (1), c) equalizing the distance between the inner layer (6) and the carcass ply (7) and the drum shoulder (12) by smoothing the shoulder area of the carcass ply (7) with finger plates (10), d) placing a bead core (11) on the carcass ply (7) at the drum shoulder (12), e) fixing the bead core (11) with a radially movable core fixation (8), f) folding over the carcass ply (7) and the inner layer (6) around the bead core (11) by filling a bellows (3), g) completing the tire blank with further steps.