U-joint Seal Alignment via Retention Insert
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing universal joint seals face challenges in effectively resisting contaminants and preventing lubricant leakage, particularly due to difficulties in proper alignment during assembly between the trunnion and bearing cup.
Innovation Solution
A seal assembly is designed with a seal support insert having radially outward protruding retention members engaging the bearing cup's retention recess, and elastomeric seals with radially inward seal lips and a dust lip that snap-fit into the trunnion's annular recess, ensuring secure positioning and effective sealing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If an elastomeric seal is positioned between the trunnion and bearing cup to form a seal, then the sealing effectiveness is improved, but the alignment difficulty during assembly increases
Solution Approach 1:
The seal assembly is divided into multiple components: a separate seal support insert with retention members and an elastomeric seal with integrated retention features. This segmentation allows each component to be optimized independently and simplifies the assembly process by enabling pre-assembly of the seal to the support insert before installation into the bearing cup.
Solution Approach 2:
The seal support insert acts as an intermediary component between the bearing cup and the elastomeric seal. It provides a structured platform with retention members that facilitate proper positioning and alignment, mediating the connection between the rigid bearing cup and the flexible seal.
2Reliability
If retention features are added to ensure proper seal positioning, then the sealing reliability is improved, but the device complexity increases
Solution Approach 1:
The retention features are merged into the elastomeric seal itself through integration of retention lips or ears that engage with corresponding features on the seal support insert. This combining eliminates the need for separate retention mechanisms and reduces overall assembly complexity while maintaining reliable seal positioning.
Solution Approach 2:
The elastomeric seal utilizes its inherent flexibility and deformability to engage with retention features on the seal support insert. The flexible material allows the seal to be installed over the retention members and then deform to lock into position, providing reliable retention without requiring complex rigid retention structures.
Data Source
AI summary
A universal joint includes a trunnion including an annular recess in an outer surface. A bearing cup is disposed on the trunnion and includes an inner diameter surface having a retention recess therein. A needle bearing assembly is disposed between an outer surface of the trunnion and the inner diameter surface of the bearing cup. A seal assembly is disposed at an open end of the bearing cup and includes a seal support insert including a radially outwardly protruding retention member engaged with the retention recess of the bearing cup. An elastomeric seal is molded to the seal support insert and includes a plurality of radially inwardly extending seal lips engaging the outer surface of the trunnion and a dust lip extending axially from the seal support insert and including a dust lip retention feature received in an annular recess of the trunnion.