Expandable Forming Drum for Tire Crown Positioning
Solution Overview
Problem
Current methods for building tires face challenges in ensuring precise positioning of the crown structure components during the tire manufacturing process, particularly for tires with high curvature ratios, leading to logistical complications and difficulties in achieving design specifications with existing rigid forming drums.
Innovation Solution
A process and plant layout utilizing a radially expandable/contractible toroidal forming drum coupled with a cylindrical carcass sleeve, allowing for closed-loop processing to ensure precise positioning and building of tire components along a closed-loop completion path, enabling efficient production with reduced cycle times and space requirements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a rigid toroidal forming drum with fixed geometry is used, then the structural stability of the drum is maintained, but the positioning precision of crown structure components deteriorates for high curvature ratio tires
Solution Approach 1:
The forming drum is designed with radially expandable and contractible elements, transforming it from a static rigid structure to a dynamic adjustable one. This allows the drum to change its radial dimensions to match the specific curvature requirements of different tire types, particularly high curvature ratio tires, thereby achieving precise positioning of crown structure components while maintaining structural stability through controlled expansion and contraction.
Solution Approach 2:
The forming drum's geometric parameters, specifically its radial dimensions, are made variable rather than fixed. By adjusting the radial expansion and contraction of the drum surface, the system can adapt to different tire curvature ratios and component positioning requirements, resolving the contradiction between maintaining structural stability and achieving manufacturing precision for various tire designs.
2Device complexity
If traditional tire building methods are used, then the process is simpler, but the cycle time increases and productivity decreases
Solution Approach 1:
The forming drum enables continuous operation by maintaining constant rotation during the tire building process. Components are applied continuously to the rotating drum surface, eliminating interruptions and waiting periods associated with traditional batch processing methods. This continuous action significantly reduces cycle time and increases productivity while the automated component application system manages the increased process complexity.
Solution Approach 2:
The forming drum is prepared in advance by setting its radial expansion state to match the required tire curvature ratio before component application begins. This preliminary configuration ensures that all subsequent component placements occur with optimal positioning precision, reducing adjustments and rework during the building process, thereby缩短ing cycle time despite the added complexity of the expandable drum system.
3Manufacturing precision
If precise positioning of crown structure components is achieved, then manufacturing precision improves, but device complexity increases
Solution Approach 1:
The expandable forming drum serves multiple functions: it provides the basic forming surface, acts as a positioning mechanism through radial adjustment, and adapts to different tire curvature ratios. This multi-functionality consolidates what would otherwise require separate devices into one system, achieving precise component positioning without proportionally increasing overall device complexity.
Solution Approach 2:
The forming drum uses adjustable radial parameters to achieve precise positioning for different tire specifications. By changing the radial expansion state of the drum, the system can precisely position crown structure components for various curvature ratios without requiring completely different forming devices, thereby managing complexity through parameter adjustment rather than structural multiplication.
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 allows for the production of tires with precise structural elements that meet design specifications, achieving high automation, reduced cycle times, and optimized plant layout, while maintaining precision and accuracy in component positioning.
Implementation Method 1
a radially expandable/contractible toroidal forming drum, matched to a curvature ratio of the tyre being processed
Data Source
AI summary
A plant for building tyres, includes: a shaping work station configured for receiving a carcass sleeve; at least one radially expandable/contractible toroidal forming drum engageable in the shaping work station; at least one work station configured for building at least one component of a crown structure on a radially external surface of a tyre being processed, defined starting from the carcass sleeve that is shaped and coupled to the forming drum; transfer devices configured for moving said forming drum along a closed-loop completion path and arranging it in proximity to the work station in order to obtain a green tyre, the closed-loop completion path being extended from an initial work station to a final work station coinciding with the shaping work station; and a pick-up device configured for picking up said green tyre decoupled from the respective forming drum.