Curved Raceway Constant Velocity Joint for Large Working Angles

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing constant velocity joints experience reduced efficiency and increased friction when operating at working angles greater than 0°, leading to potential cage damage and failure, especially with obliquely extending raceways.

Innovation Solution

The design incorporates axially extending race grooves with at least one curved section and a linear section, allowing for high torque transmission and efficiency even at large working angles, reducing the force exerted on the cage and extending its service life.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If obliquely extending raceways are used to increase efficiency at large working angles, then efficiency is improved, but the force between the cage and balls increases causing damage and failure

Engineering Contradiction:

ImproveefficiencyVSAvoidcage durability

Core Design Contradiction:

Loss of energyVSReliability

Solution Approach 1:

The patent applies curvature to the race groove paths, specifically designing them with arc-shaped sections instead of purely linear oblique courses. This curved geometry optimizes the contact between balls and raceways, reducing concentrated forces on the cage while maintaining efficient torque transmission at large working angles

Inventive Principle:

Principle #14Spheroidality (Curvature)

Solution Approach 2:

The patent changes the geometric parameters of the raceways by introducing curved sections with specific radii and angles. This parameter modification allows the raceway to adapt its contact characteristics, reducing cage force at large working angles while preserving efficiency benefits

Inventive Principle:

Principle #35Parameter changes

2Power

If linear oblique raceways are used, then torque transmission is maintained, but efficiency is reduced due to friction and heat at working angles greater than 0°

Engineering Contradiction:

Improvetorque transmissionVSAvoidefficiency

Core Design Contradiction:

PowerVSLoss of energy

Solution Approach 1:

The curved sections in the raceways optimize the ball-raceway contact geometry, enabling efficient torque transmission across a range of working angles by distributing contact forces more effectively than linear oblique paths

Inventive Principle:

Principle #14Spheroidality (Curvature)

3Ease of manufacture

If purely linear oblique raceways are used, then manufacturing is simplified, but cage force increases leading to premature failure

Engineering Contradiction:

Improveraceway fabricationVSAvoidcage service life

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The curved raceway sections, while slightly more complex to manufacture than linear paths, can be efficiently produced using conventional machining or forming processes. The curvature radius and path are designed to be practical for manufacturing while significantly improving cage durability

Inventive Principle:

Principle #14Spheroidality (Curvature)

Data Source

PatentUS12498000B2Constant velocity joint

Publication Date: 2025.12.16 AB SKF SKF PATENT DEPARTMENT

AI summary

A constant velocity joint includes an outer part having an opening and a plurality of axially extending race grooves in the opening, an inner part at least partially located in the opening and having an outer surface with a plurality of axially extending race grooves, and a plurality of balls located between in inner and outer parts in the grooves. A first subset of the race grooves in the outer part and/or a first subset the race grooves in the inner part includes a section that follows a curved path in the axial direction.