Studless Tire Tread Layout for Snow Braking and Low Rolling Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional studless tires for ice/snow surfaces face issues with uneven wear and increased rolling resistance due to complex block shapes and additional rubber volume, which affect on-snow performance, particularly braking performance and affinity with anti-lock braking systems (ABS).
Innovation Solution
A tire design featuring alternately positioned center and second blocks with linearly symmetric shapes, higher block rigidity, and strategically placed width direction sipes and grooves to enhance contact area and edge effect, while minimizing rubber volume and rolling resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a bottom-up portion is provided in a groove portion between adjacent blocks to connect them, then block rigidity is improved and uneven wear is suppressed, but rubber volume increases and rolling resistance increases
Solution Approach 1:
The groove portion between adjacent blocks is segmented into a first groove portion and a second groove portion that are separated by a ridge portion. This segmentation allows the groove to provide block connection and rigidity enhancement without requiring a continuous bottom-up portion, thereby reducing rubber volume and rolling resistance while maintaining the necessary structural integrity.
2Reliability
If complex block shapes with many fine grooves are used, then on-snow performance is improved, but rubber volume increases and rolling resistance increases
Solution Approach 1:
Fine grooves such as sipes are selectively formed only in specific regions where they are most effective for on-snow performance, rather than uniformly across all blocks. The groove portion between blocks is designed with specific local characteristics (first and second groove portions separated by a ridge) to provide necessary rigidity without excessive rubber volume, thereby maintaining on-snow performance while reducing rolling resistance.
3Duration of action of stationary object
If block rigidity is increased to suppress uneven wear, then wear durability is improved, but on-snow performance (braking and driving performance) deteriorates
Solution Approach 1:
The groove portion is segmented into first and second groove portions separated by a ridge portion, creating a balanced structure that provides sufficient block rigidity to suppress uneven wear while maintaining the flexibility and deformation characteristics necessary for on-snow braking and driving performance. This segmented design avoids excessive rigidity that would harm snow performance.
4Stability of the object's composition
If rubber volume is increased to connect adjacent blocks, then block connection is improved, but rolling resistance increases
Solution Approach 1:
The groove portion connecting adjacent blocks is segmented into separate first and second groove portions with a ridge portion between them. This segmentation reduces the continuous rubber volume required for block connection while maintaining adequate structural connection and stability, thereby reducing rolling resistance without compromising block connection integrity.
Data Source
Figure 1
Figure 2
Figure 3~5
AI summary
In the pneumatic tire (10), the ratio TW/SW of the ground contact width TW of the tire and the maximum width SW of the tire is 0.75 to 0.95. The tire width direction outside end of the belt layer extends in the tire circumferential direction and is positioned outside in the tire width direction than the circumferential direction groove formed most outside in the tire width direction. A width direction sipe (111) extending in the tire width direction and closest to the tire circumferential direction end portion of the block (100) and a width direction sipe (112) adjacent to the width direction sipe (111) and extending in the tire width direction are formed in the block (100), and a distance (L 11) from the tire circumferential direction end portion to the width direction sipe (111) along the tire circumferential direction is longer than a distance (L 12) from the width direction sipe (111) to the width direction sipe (112) along the tire circumferential direction.