Torsional Vibration Damper Stop Design for Torque Shock Absorption
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rotary vibration damping assemblies face challenges in effectively managing high rotational accelerations and torque shocks, leading to potential damage and noise issues due to inadequate stop formations during engine startup and shutdown.
Innovation Solution
A rotational-speed-adaptive absorber with a deflection mass carrier and elastically deformable stop formations, where the stop material volume is optimized to absorb kinetic energy through deformation, ensuring a sufficient volume for impact absorption without hard impacts, using elastomer materials like AEM, FKM, HNBR, or EPDM with specific Shore A hardness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the stop formation is made rigid to prevent deflection mass movement, then damage and noise are prevented, but impact energy cannot be absorbed and hard impacts occur
Solution Approach 1:
The stop formation uses elastically deformable material instead of rigid material, changing the mechanical property parameter from rigidity to elastic deformability. This allows the stop formation to absorb impact energy through elastic deformation while still preventing damage and noise, resolving the contradiction between energy absorption and damage prevention.
Solution Approach 2:
The elastically deformable stop formation is positioned to contact the deflection mass before hard impact occurs, providing cushioning in advance. The elastic material deforms to absorb impact energy, preventing hard impacts and associated damage and noise, thus implementing beforehand cushioning.
2Loss of energy
If the stop material volume is increased to absorb more kinetic energy, then impact absorption capability improves, but device complexity and space requirements increase
Solution Approach 1:
By changing the material parameter to elastically deformable material with optimized volume, the stop formation achieves high energy absorption capability without requiring large volume. The elastic deformability allows efficient energy absorption per unit volume, reducing the need for large stop material volume and simplifying the device structure.
3Loss of energy
If the stop formation is made softer to increase elastic deformability, then impact absorption improves, but the stop formation may fail under maximum rotational accelerations
Solution Approach 1:
The stop formation uses elastically deformable material with optimized elastic properties, not overly soft material. The material parameters are selected to provide sufficient elastic deformability for impact absorption while maintaining adequate strength to withstand maximum rotational accelerations, resolving the contradiction between softness and strength.
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 absorbs kinetic energy during high rotational speeds and accelerations, preventing damage and noise by ensuring a sufficient volume of deformable stop material is available, maintaining the elastic deformability of the stop formation even under maximum expected conditions.
Implementation Method 1
the elastically deformable stop formation comprises elastic stop material which is mounted fixedly with respect to the deflection mass carrier
Implementation Method 2
deflection masses are forced radially outward with respect to an axis of rotation, and thus into their basic relative position with respect to the deflection mass carrier, by centrifugal forces that act during rotational operation
Data Source
AI summary
The disclosure relates to a torsional vibration damping assembly comprising a deflection mass carder capable of rotation about a rotational axis and deflection masses mounted following one another in a circumferential direction on the deflection mass carrier and deflectable from a basic relative position, wherein the radial position of the deflection masses with respect to the rotational axis changes on deflection from the basic relative position, with each deflection mass being mounted deflectably in both circumferential directions from the basic relative position by coupling formations on the deflection mass carrier, with a resiliently deformable stop formation being provided and assigned to each deflection mass to haft a deflection movement of the deflection mass once a stop deflection has been reached, with the resiliently deformable stop formation comprising a resilient stop material which is fixedly mounted with respect to the deflection mass carder, with the following ratio R being applicable in the assignment to each deflection mass: R=VE/E wherein VE is an effective stop material volume assigned to a deflection mass on reaching the stop deflection by deformation of the resilient stop material and E is an impact metric relative to the kinetic energy of a deflection mass on reaching the stop deflection, and wherein the following applies for the ratio R: 0.15×10−3 m2/kg≤R≤0.6×10−3 m2/kg.