Inclined Edge Blades in Segmented Tire Molds for Sipe Continuity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing tire molds face challenges in designing complex tread patterns without damaging blades due to forces exerted during demolding or collision during mold closure, and there is a need to reduce blade breakages and gaps in the tread pattern.
Innovation Solution
A tire mold design where the tread mold portion is divided into multiple mold segments with interlocking or inclined laterally extending blades at the transverse edges, allowing for reduced forces on the blades during demolding and improved closure without damaging the blades.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If blades are positioned at transverse edges of mold segments to create complex tread patterns, then tread pattern complexity is improved, but blade breakage risk increases due to forces during demolding
Solution Approach 1:
The mold is divided into multiple segments with blades positioned at transverse edges, allowing complex tread patterns to be created while reducing the span of each blade to minimize bending moments and breakage risk
Solution Approach 2:
The mold segments are designed to move dynamically during closing and opening, with blades at transverse edges experiencing reduced relative motion and friction forces compared to conventional radial blade arrangements
2Ease of operation
If mold segments are moved into contact during closure, then mold closing is achieved, but blade collision damage occurs at transverse edges
Solution Approach 1:
Instead of having blades extend radially outward from the mold segment face, the blades at transverse edges are positioned to interlock with neighboring segments, inverting the conventional blade orientation to prevent collision during closure
Solution Approach 2:
Blades from adjacent mold segments nest together at the transverse edges, with interlocking profiles that guide the segments into proper alignment during closing while preventing blade collision
3Device complexity
If blades extend radially from mold segment face, then simple blade design is maintained, but blade breakage increases due to friction forces during demolding
Solution Approach 1:
The blade configuration varies by location: central blades extend radially for simple design, while transverse edge blades are positioned to interlock with neighboring segments, reducing relative motion and friction forces during demolding
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
A tire mold comprising a tread mold portion is disclosed. The tread mold portion is divided in a tire circumferential direction into a plurality of mold segments (15) each having an inner face (17) curved along the circumferential direction according to an arc defined by an angle α, each mold segment (15) having two transverse edges (19, 21) and being movable in a respective operation direction between i) an opened position, in which the mold segments (15) are spaced from each other and ii) a closed position in which two neighboring mold segments (15) are in contact with each other by one of their transverse edges (19, 21), and each of the mold segments (15) comprising a plurality of laterally extending blades forming projections from the inner face (17) of the mold segment (15) for molding laterally extending sipes on a tire tread surface. The mold segments (15) have, according to their length, a first end portion (25), a second end portion (29) and a central portion (27) between the first (25) and the second end portions (29). Laterally extending blades of the central portion (27) are extending in the operating direction (OD). Laterally extending blades of one or more of the first end portion (25) and the second end portion (29) are inclined blades that extend in a direction forming an angle β with the operating direction (OD). The value of the angle β is less than half of the value of the angle α.