Pneumatic Tyre Tread with Chamfered Incisions for Hysteresis Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current tire treads face challenges in reducing rolling resistance and energy consumption due to hysteresis-related energy losses, which are influenced by the deformation cycles and forces exerted during tire rolling, particularly in the contact zone between the tire and the ground.
Innovation Solution
The tire tread design incorporates a central zone with circumferential bands and transverse incisions, where the incisions are strategically positioned and chamfered to delay contact with the ground, reducing deformation and energy losses by hysteresis, and optionally includes bearing studs to further minimize incision volume and deformation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If transverse incisions are made in the tread to reduce hysteresis energy losses, then energy consumption is reduced, but the incisions cause additional deformation and hysteresis losses when closed in the contact zone
Solution Approach 1:
The tread is segmented into multiple circumferential bands separated by transverse incisions, creating discrete blocks that can independently deform. This segmentation allows the incisions to remain open during rolling, reducing hysteresis losses while maintaining structural integrity through the distributed block configuration.
Solution Approach 2:
The incisions are designed with specific geometric characteristics (width, depth, orientation) that vary locally across the tread surface. By optimizing the local geometry of each inciction, the design achieves minimal hysteresis loss in the contact zone while maintaining overall tread functionality.
2Loss of energy
If the width of incisions is reduced to improve closure, then hysteresis losses decrease, but manufacturing precision requirements increase
Solution Approach 1:
The design optimizes the inciction width parameter within a specific range (0.5mm to 2mm) to achieve the desired balance between hysteresis reduction and manufacturing feasibility. By establishing this parameter range, the invention makes the system less sensitive to minor manufacturing variations while still achieving energy loss reduction.
3Stability of the object's composition
If the tread is made more rigid to maintain shape, then deformation is reduced, but energy losses by hysteresis increase
Solution Approach 1:
The tread design incorporates dynamic characteristics by allowing controlled deformation of the blocks between incisions. The blocks can flex and adapt to contact forces while the incisions remain substantially open, creating a dynamic response that reduces hysteresis losses compared to a completely rigid structure.
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 design effectively reduces energy losses by hysteresis, enhancing the energy performance of the tire by limiting deformation and maintaining rigidity, while allowing for non-directional tire functionality.
Implementation Method 1
These energy losses are dependent on the hysteresis characteristics of the rubber compounds used in the tread. Under the effect of shear forces and compressive forces, the blocks are crushed and the opposite side walls of said blocks are deformed by approaching each other. This deformation of the side walls leads to energy losses by hysteresis.
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
The invention relates to a pneumatic tyre tread of width W. This tread comprises a central region of a width of between 70% and 80% of the width W of the tread. The central region comprises one or more circumferential strips (17), each circumferential strip of the central region being delineated by two grooves of a width greater than or equal to 2 mm. Each circumferential strip of the central region comprises a contact surface intended to come into contact with the ground and a plurality of transverse incisions (19a, 19b, 19c) distributed uniformly in the circumferential direction. Each incision on the contact surface has a width of less than 2 mm so as to define an average circumferential cuts ratio. This average circumferential cuts ratio is between 0.5 times and 1.5 times the ratio between a mean thickness (E) of the circumferential strip and a mean circumferential radius of curvature (Rc) of said circumferential strip. The incisions divide the circumferential strip into a succession of blocks (21, 21b, 21c), each block having two edges (22a, 22b, 22c, 24) that intersect the contact surface of the circumferential strip. For each block of the circumferential strip, at least one of the edges of said block is extended radially by an inclined part (29a, 29b, 29c, 31) that forms a chamfer. This inclined part connects the edge to a side wall of the block in order to generate a circumferential offset between said edge and said side wall of the block.