Inclined Surface Kinematic Mount for Thermal Expansion Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High positional accuracy in optical apparatuses is compromised due to temperature changes, leading to misalignment and distortion, especially in precision instruments like telescopes and artificial satellites, where materials with different thermal expansion coefficients cause deformation and degrade optical performance.
Innovation Solution
A holding apparatus with inclined surfaces that maintain a constant distance along a reference axis, using kinematic mounts and preload application units to prevent misalignment by allowing spherical surfaces to move along the inclined surfaces, thereby compensating for thermal expansion differences between the optical element and the holding apparatus.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If kinematic mounts are used to hold the optical element, then positioning repeatability is improved, but positioning accuracy along the reference axis deteriorates when temperature changes occur
Solution Approach 1:
The invention introduces a movable groove component that allows the ball to move dynamically in response to temperature-induced deformation. This dynamic adjustment enables the system to maintain positioning accuracy along the reference axis while preserving the positioning repeatability provided by the kinematic mount structure.
Solution Approach 2:
The invention changes the geometric parameters of the holding structure by introducing an inclined surface with a specific angle. This angular parameter allows the contact point to shift along the inclined surface when temperature changes occur, thereby maintaining the distance between reference points along the reference axis while accommodating thermal expansion differences.
2Adaptability or versatility
If materials with different thermal expansion coefficients are used for the holding apparatus and optical element, then adaptability to performance requirements is improved, but misalignment due to thermal deformation worsens
Solution Approach 1:
The invention converts the harmful effect of differential thermal expansion into a beneficial mechanism. By designing the holding structure with an inclined surface, the thermal deformation causes the ball to move along the groove and change the contact point on the inclined surface, which in turn adjusts the holding position to compensate for the deformation and maintain alignment accuracy.
3Manufacturing precision
If a movable groove component is added to allow ball movement, then positioning accuracy under temperature change is improved, but device complexity increases
Solution Approach 1:
The invention segments the holding structure into distinct functional components: the kinematic mount elements (ball and V-groove), the movable groove component, and the inclined surface. This segmentation allows each component to perform its specific function while working together to achieve temperature-compensated positioning, making the overall system manageable despite the added complexity.
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 solution effectively maintains the relative positions of optical elements and structures across varying temperatures, preventing misalignment and ensuring consistent optical performance by adjusting contact points on inclined surfaces, thus addressing the challenge of thermal expansion-induced deformation.
Implementation Method 1
Many constituent elements have a limited selection of materials in order to achieve their desired performance. For example, it is conceivable that a low thermal expansion material such as Invar may be used for a holding apparatus that holds an optical element, but in the case where glass constituting the optical element has a high thermal expansion coefficient
Data Source
AI summary
A holding apparatus includes a structure and configured to hold an object so that a distance from a reference point of the structure to a reference point of the object in a direction along a reference axis is kept at a constant value. The holding apparatus further includes a plurality of holding members, each supported by the structure, including an inclined surface that is inclined relative to a plane orthogonal to the reference axis, and configured to hold the object via the inclined surface. The inclined surfaces are inclined so that the distance falls within a tolerance even if temperature of the object and the plurality of holding members change.