Zigzag Tire Sipes With Tie-Bars for Ice Grip and Load Durability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Tires with sipes for winter use face challenges in maintaining on-ice performance and load durability due to strain concentration and crack formation at the sipe bottoms under ground load.
Innovation Solution
The tire design incorporates zigzag-shaped sipes with tie-bars and widening portions in the sipe bottoms, which are located in a harder base rubber layer, to distribute strain and enhance rigidity, improving load durability and on-ice performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If sipes are provided in the tread portion for winter use, then on-ice performance is improved, but strain concentrates on the sipe bottoms and cracks occur, reducing load durability
Solution Approach 1:
The patent applies local quality by providing widening portions at specific locations (sipe bottoms) rather than uniformly across the entire sipe structure. The widening portions are strategically placed where strain concentration occurs, creating localized structural reinforcement exactly where needed to prevent crack initiation while maintaining the overall sipe functionality for ice performance.
Solution Approach 2:
The sipe structure is segmented into multiple portions (first portion, second portion, third portion) with the middle portion containing widening portions. This segmentation allows different sections of the sipe to have different structural characteristics - the widening portions provide reinforcement against strain concentration while the other portions maintain flexibility and cutting ability for ice traction.
2Reliability
If the tread rubber is made softer to improve on-ice performance, then water absorption and flexibility are enhanced, but the rigidity decreases and strain concentration at sipe bottoms increases
Solution Approach 1:
The patent implements local quality by creating widening portions with different physical properties at specific locations within the sipe structure. These widening portions have increased cross-sectional area and are positioned to provide localized rigidity and strain distribution exactly where needed, while the rest of the tread rubber maintains its soft, flexible characteristics for optimal ice contact and water absorption.
Solution Approach 2:
The tread rubber composition is designed as a composite structure with different hardness levels - the base tread rubber has lower hardness for flexibility and water absorption, while the widening portions have higher hardness for rigidity and strain resistance. This composite approach allows the tire to simultaneously achieve both softness for ice performance and localized rigidity for strain prevention.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A tire includes first blocks each with a zigzag first sipe. The first sipe includes a sipe bottom and a tie-bar locally raising outwardly in a tire radial direction from the sipe bottom so as not to reach the ground contact surface to divide the first sipe into first and second portions. The sipe bottom of the first portion communicates with a first widening portion which has a circular cross-section and has a groove width greater than that of the first portion. The first widening portion extends linearly over the entire length. The sipe bottom of the second portion communicates with a second widening portion which has a circular cross-section and has a groove width greater than that of the second portion. The second widening portion extends linearly over the entire length. The first widening portion does not communicate with the second widening portion.