Track Chain Pin Retention and Stress Distribution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current track chain designs face issues with pin retention, leading to loose pins and maintenance challenges, and suffer from stress concentrations that cause fracturing or spalling under heavy loads, especially on uneven terrain.
Innovation Solution
A pin retention device comprising a bolt, washer, nut, and spacer is used to secure the track pin, and the track chain members are designed with contoured roller paths and increased contact surfaces to distribute stress, reducing the likelihood of pin egress and stress concentrations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a snap ring with a welded plate is used to retain the pin, then the pin retention is improved, but the ease of servicing the pin deteriorates
Solution Approach 1:
The pin retention system is segmented into separate functional components: the snap ring provides retention while the separate plate structure allows access. This segmentation enables the pin to be serviced by removing the plate without affecting the snap ring's retention function, resolving the contradiction between reliable retention and ease of servicing.
Solution Approach 2:
A separate plate structure acts as an intermediary between the pin and the external environment. This plate can be removed to access the pin for servicing, while the snap ring remains in place to maintain retention. The intermediary plate resolves the conflict by providing a removable barrier that doesn't compromise the retention mechanism.
2Strength
If the track chain member is hardened to withstand stress concentrations, then the strength is improved, but the manufacturing precision deteriorates
Solution Approach 1:
Instead of uniformly hardening the entire track chain member, the invention applies hardening selectively to specific high-stress areas where stress concentrations occur. This localized approach provides the necessary strength enhancement while minimizing the impact on overall manufacturing precision and avoiding unnecessary hardening of areas where it is not needed.
Solution Approach 2:
The invention modifies the hardening parameters (such as hardening depth, temperature, and duration) to optimize the balance between strength and manufacturability. By carefully controlling these parameters, the track chain member achieves sufficient hardness in critical areas while maintaining dimensional stability and avoiding excessive distortion that would compromise manufacturing precision.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A track chain member (600) comprises a shoe member (602) defining a track chain traveling direction (T) and a lateral direction (L) perpendicular to the track chain traveling direction (T) and a first rib (606) defining a first concave radial portion (636).