Flexible Transmission Drive Joint with Flat Thrust Faces
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing ball drive systems in drilling apparatuses experience high point loading along the line of contact between drive balls and ball pockets, leading to deformation, cracking, and potential catastrophic failure.
Innovation Solution
A ball drive system featuring flat faced drive balls and drive pockets with flat thrust faces, which reduces point loading by distributing the thrust forces over a larger area, and includes a removable, hardened thrust ball insert for extended wear and easy replacement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If semi-circular ball pockets with thin line contact geometry are used, then torque transfer is achieved, but high point loading occurs causing deformation and damage to ball pockets
Solution Approach 1:
The ball pocket geometry is modified to have a flat thrust face instead of a semi-circular shape, creating a localized area of increased contact surface. This local geometric change distributes the thrust force over a larger area, reducing point loading while maintaining torque transfer capability. The flat thrust face is specifically designed to match the spherical shape of the drive ball, ensuring optimal force distribution.
Solution Approach 2:
The contact interface is transitioned from a thin line contact (one-dimensional) to a surface contact (two-dimensional) by introducing the flat thrust face. This dimensional change increases the contact area between the drive ball and ball pocket, thereby distributing the thrust force over a larger area and reducing point loading on the ball pocket.
2Force
If traditional drive ball geometry is used, then torque transfer is achieved, but point loading is not evenly distributed leading to cracking and potential catastrophic failure
Solution Approach 1:
The ball pocket is designed with a flat thrust face that provides a localized area of improved force distribution. This local geometric modification ensures that the thrust force from the drive ball is evenly distributed across the flat surface, preventing stress concentration and reducing the risk of cracking while maintaining torque transfer functionality.
3Adaptability or versatility
If ball pockets are designed for full multidirectional articulation, then drive shaft articulation is achieved, but high point loading occurs on the contact surface
Solution Approach 1:
The flat thrust face is introduced as a local geometric feature within the ball pocket that maintains the articulation capability while improving force distribution. The flat surface is specifically positioned to contact the drive ball in a way that distributes thrust forces, allowing the joint to accommodate angular movements without concentrating stress on a narrow line contact.
Data Source
AI summary
A driveline includes a rotor adaptor and a bearing adaptor coupled to opposite ends of a drive shaft. The rotor adaptor includes a first plurality of drive pockets. Each of the first plurality of drive pockets receives a drive ball rotatably held between each of the first plurality of drive pockets and the end of the drive shaft. The bearing adaptor includes a second plurality of drive pockets. Each of the second plurality of drive pockets receives a drive ball rotatably held between each of the second plurality of drive pockets and the opposite end of the drive shaft. Each of the plurality of drive balls includes a flat surface and each of the first plurality of drive pockets and the second plurality of drive pockets includes a flat thrust face. The flat surface receives a rotational force from the flat thrust face in response to rotating the rotor adaptor.