Universal Joint Torque Transmission via Monolithic Cross
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rotary steerable drilling systems face limitations in load capability, especially for smaller borehole sizes, due to complex designs and inadequate transmission of torque and axial loads.
Innovation Solution
A universal joint system with a high load carrying capability is achieved through load-sharing mechanisms, including torque transmission via universal joint pins and side faces of a monolithic cross, and integral pins with a split yoke/clevis assembly, allowing for pressure-sealed fluid flow and integrated axial load transfer without additional thrust bearings.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If a multitude of ceramic balls in pockets are used to transmit torque, then torque transmission is achieved, but the device complexity increases and load capability is limited
Solution Approach 1:
The patent combines multiple ceramic balls into a single toroidal (doughnut-shaped) element that performs the same torque transmission function. This merging reduces the number of components and simplifies the overall structure while maintaining the load transmission capability through the distributed contact geometry of the toroid with the cylindrical channels in the torque ring
Solution Approach 2:
The toroidal element serves multiple functions: it transmits torque through its contact with cylindrical channels, maintains radial clearance for fluid flow, and provides structural support. This multi-functionality reduces the need for separate components and simplifies the universal joint design
2Force
If separate spherical thrust bearings are used to transmit axial load, then axial load transmission is achieved, but the device complexity increases
Solution Approach 1:
The patent integrates axial load transmission into the universal joint structure itself through the toroidal element and its interaction with the torque ring and cross assembly. The geometry of these components is designed to handle axial loads directly, eliminating the need for separate thrust bearing assemblies and reducing overall device complexity
3Volume of moving object
If a compact universal joint design is used, then the device size is reduced, but the load carrying capability is limited
Solution Approach 1:
The patent employs ceramic material for the toroidal element, which provides high strength-to-weight ratio and exceptional load-bearing capability in a compact form. The ceramic material allows the small toroid to withstand high contact stresses from torque transmission while maintaining a compact overall size of the universal joint assembly
Solution Approach 2:
The toroidal (doughnut-shaped) geometry of the ceramic element provides optimized stress distribution and contact mechanics. The curved surfaces of the toroid interacting with cylindrical channels create favorable stress patterns that maximize load carrying capability while minimizing the size of the component
Data Source
AI summary
A technique facilitates downhole drilling applications by providing a universal joint. The universal joint has a high load carrying capability presented in a compact and simple configuration. The high load carrying capability is achieved by techniques employing unique load transfer mechanisms. For example, higher load capability may be provided by a load sharing principal in which torque loads are jointly transmitted through universal joint pins and the side faces of a universal joint cross. The higher load capability also may be achieved by transferring loads through a monolithic cross having integral pins and a split yoke/clevis assembly. In another embodiment, higher load capability results from using universal joint pins inserted from the inside of the universal joint and screwed outwardly until full engagement with the joint yokes is achieved. Each of the universal joint embodiments also may be designed to enable pressure-sealed flow of drilling mud through the joint.