Parallel Bearing Structure for High-Speed Rotor Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing contact bearings rely heavily on high-performance lubricants, while non-contact air bearings experience excessive frictional forces at high rotational speeds, leading to wear and damage.
Innovation Solution
A parallel bearing system comprising a contact rotary shaft bearing and a non-contact stator bearing with clearance, along with intermediate contact bearings, reduces relative rotational speed and frictional forces by decoupling shaft diameter and rotational speed, allowing for adaptive synchronous rotation and reduced lubricant dependency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If high-performance lubricating oils are used in bearings with high DN factors, then the bearing can withstand heavier loads and higher critical rotational speeds, but the cost increases significantly
Solution Approach 1:
The bearing system is divided into two independent bearing units: a contact bearing (ball or roller bearing) and a non-contact air bearing. Each bearing handles different aspects of the load and speed requirements. The contact bearing supports radial and axial loads, while the air bearing provides non-contact support and reduces friction at high speeds, eliminating the need for expensive high-performance lubricants in a single bearing system
Solution Approach 2:
The patent combines two different bearing technologies (contact bearing and air bearing) into a single integrated bearing system. The contact bearing and air bearing work together to support the rotary shaft, with the air bearing providing non-contact support that reduces friction and allows high-speed operation without requiring expensive lubricants
2Force
If the diameter of the rotary shaft is increased to withstand heavier loads, then the load capacity increases, but the critical rotational speed decreases and higher DN factors are required
Solution Approach 1:
The bearing system separates the load support function (handled by the contact bearing with appropriate diameter) from the speed support function (handled by the air bearing). This allows the shaft diameter to be optimized for load capacity without being constrained by the critical rotational speed limitation, as the air bearing compensates by providing non-contact support that reduces friction and enables high-speed operation
3Reliability
If non-contact air bearings are used to reduce friction, then lubricant dependency decreases, but excessive frictional forces occur at high rotational speeds leading to wear and damage
Solution Approach 1:
The patent merges the advantages of both contact bearings (low friction when properly lubricated) and air bearings (non-contact support) by using them together. The contact bearing provides stable support with minimal friction through proper lubrication, while the air bearing provides non-contact support that prevents wear. The combination ensures that neither bearing operates alone under extreme conditions, distributing the frictional forces and preventing the excessive wear that would occur if the air bearing operated independently at high speeds
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The parallel bearing system is cost-effective, reduces frictional forces, extends the service life of components, and allows for adaptive rotational speed adjustment, making it suitable for high-speed applications like microturbines with reduced lubricant requirements.
Implementation Method 1
For non-contact bearings such as radial air bearings, the support function depends on pressurized air between the shaft and the inner ring of the bearing
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present disclosure provides a parallel bearing, including a rotary shaft bearing (1) and a stator bearing (2), wherein the rotary shaft bearing (1) is a contact bearing, and the rotary shaft bearing (1) is sleeved on a rotary shaft (100); and the stator bearing (2) is a non-contact bearing, the stator bearing (2) is sleeved on the rotary shaft bearing (1), and a clearance is provided between the stator bearing (2) and the rotary shaft bearing (1). The parallel bearing is cost-effective, reduces the relative rotational speed of each stage of bearing, breaks through the limitation of the theoretical DN factor and has the low dependency on the lubricating oil. In the rotor system having the parallel bearing, rotational speeds of multiple parallel bearings on the same rotary shaft can be adaptively adjusted to achieve the synchronous rotation, and thus the rotor system has the desired stability in high-speed operation.