Symmetric Flexure Bearings for Non-Rotating Cryocooler Support
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional flexure bearings in cryocoolers allow moving components to rotate, causing disturbances and off-axis vibrations, which can affect the operation of cryocoolers and connected systems.
Innovation Solution
Non-rotating flexure bearings with symmetric flexure arms connecting an outer hub to an inner hub, secured to a support structure and a device, designed to prevent rotation by deforming in a manner that cancels out rotational motion, thereby maintaining precise positioning and reducing exported disturbances.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If conventional flexure bearings with spiral arms are used, then components can be connected between moving mechanism and support structure, but rotation and off-axis vibrations occur causing disturbances
Solution Approach 1:
The patent applies asymmetry by using symmetric sets of flexure arms (where each set contains arms that are mirror images of each other) rather than a simple spiral pattern. This symmetric configuration within sets, arranged in multiple sets, creates a balanced structure that prevents rotational motion and cancels off-axis vibrations, thereby eliminating the harmful disturbances generated by conventional asymmetric spiral designs
2Reliability
If components are secured in fixed positions, then proper operation is ensured and disturbances are reduced, but rotation still occurs with conventional flexure bearings
Solution Approach 1:
The patent employs the counterweight principle by arranging symmetric flexure arms in multiple sets where the deformation of one arm is counterbalanced by the deformation of its symmetric counterpart. This creates a balanced force system that prevents rotational instability while maintaining reliable fixed positioning of components, ensuring both proper operation and rotational stability
3Object-generated harmful factors
If symmetric flexure arms are used, then rotation is prevented and vibrations are reduced, but device structure becomes more complex
Solution Approach 1:
The patent applies segmentation by dividing the flexure bearing into multiple independent sets of symmetric flexure arms rather than using a single complex spiral structure. Each set contains symmetric arms that can be designed and manufactured separately, then assembled together. This segmentation reduces overall device complexity while achieving the goal of preventing rotation and reducing vibrations
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 non-rotating flexure bearings effectively secure components in place, minimizing rotation and off-axis vibrations, ensuring precise alignment and reducing disturbances in cryocooler operation, allowing for extremely low levels of exported disturbances.
Implementation Method 1
deforming flexure arms in the flexure bearing as a result of the displacement
Data Source
AI summary
A system includes a device, a support structure, and a flexure bearing configured to connect the device to the support structure. The flexure bearing includes an outer hub and an inner hub, where the hubs are configured to be secured to the support structure and to the device. The flexure bearing also includes multiple sets of flexure arms connecting the outer and inner hubs. Each set of flexure arms includes symmetric flexure arms. The flexure bearing could include three sets of flexure arms positioned radially around a central axis of the flexure bearing and having a spacing of about 120°. Each flexure arm can follow a substantially curved path between the outer hub and the inner hub. The symmetric flexure arms in each set can be configured such that twisting of one flexure arm in one set is substantially counteracted by twisting of another flexure arm in that set.