Seismic Support Platform With Variable-Friction Damper Centering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing passive dampers for semiconductor manufacturing tools struggle to optimize friction force across a wide range of displacement magnitudes, leading to potential damage from impulse forces or insufficient vibration damping during seismic events.
Innovation Solution
A support platform with displacement control assemblies that utilize passive dampers with inclined track portions to increase frictional force with displacement magnitude, providing controlled damping and centering mechanisms to prevent damper displacement to the track ends.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If passive dampers use constant friction force, then the structure is simple, but the damper cannot effectively suppress large displacement seismic events without causing impulse forces
Solution Approach 1:
The patent applies the dynamics principle by making the friction force variable rather than constant. The inclined track portions cause the normal force between the damper and track to increase with displacement magnitude, thereby dynamically adjusting the friction force to match the severity of the seismic event. This resolves the contradiction by enabling effective suppression of large displacements while avoiding excessive impulse forces at small displacements.
Solution Approach 2:
The patent changes the friction force parameter from a constant value to a variable value that increases with displacement magnitude. The inclined track geometry transforms the displacement parameter into a corresponding normal force parameter, which directly controls the friction force. This parameter change enables the damper to adapt its damping characteristic to different seismic event intensities.
2Reliability
If passive dampers increase friction force for large displacement, then seismic suppression improves, but impulse forces may damage the tool at small displacement
Solution Approach 1:
The dynamics principle enables the friction force to dynamically adapt to displacement magnitude. At small displacements, the normal force and thus friction force remain low, preventing impulse damage. At large displacements, the normal force increases proportionally, providing strong seismic suppression. This dynamic adaptation resolves the contradiction between suppression effectiveness and impulse force avoidance.
Solution Approach 2:
The inclined track portions act as a beforehand cushioning mechanism by gradually increasing the friction force as displacement increases. Rather than applying a sudden large force, the system progressively builds up the damping force, cushioning the tool against both small vibrations and large seismic events without causing impulse damage.
3Device complexity
If the damper track is straight, then the mechanism is simple, but the damper cannot provide centering function during seismic events
Solution Approach 1:
The patent applies asymmetry by introducing inclined track portions that create an asymmetric normal force distribution relative to the vertical centerline. When the damper displaces from center, the inclined track generates a restoring normal force component that pushes the damper back toward the center position. This asymmetric geometry provides the centering function while maintaining relatively simple track structure.
Solution Approach 2:
The inclined track portions create a counteracting normal force that opposes the displacement from center position. This counterforce acts as a mechanical restoring force, similar to a spring, that continuously pushes the damper back toward the neutral position, providing automatic centering without additional active control mechanisms.
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 suppresses seismic displacement, reduces impulse forces, and ensures smooth recentering of the damper, thereby protecting the semiconductor manufacturing tools from damage.
Implementation Method 1
The inclined track portions are each inclined with respect to the central track portion to increase frictional force between the damper and the track with increasing distance of the damper away from the central track portion
Implementation Method 2
a damper secured to one of the support plate or the brake plate and frictionally engaging a track of the other of the support plate or the brake plate
Data Source
AI summary
A support platform is configured to support at least a portion of the weight of an associated semiconductor manufacturing tool, such as a furnace, when the associated semiconductor manufacturing tool is disposed on the support platform. The support platform comprises a base, a support plate disposed on the base and configured to move respective to the base, a brake plate arranged in fixed position respective to the base, and a damper secured to one of the support plate or the brake plate and frictionally engaging a track of the other of the support plate or the brake plate. The track includes a central track portion and inclined track portions extending away from the central track portion on respective first and opposite second sides of the central track portion. The inclined track portions are each inclined with respect to the central track portion.