Centrifugal Pendulum Damping Device with Layered Elastomer Materials
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Pendular damping devices in motor vehicle transmission systems are sensitive to gravity, leading to undesired displacements and noise generation, especially at low engine rotation speeds where centrifugal force is less than gravity, causing pendular bodies to fall and collide, exciting intrinsic modes and generating noise.
Innovation Solution
A pendular damping device with a support and pendular body featuring layers of materials, where a lower-density material, such as an elastically deformable elastomer, is sandwiched between layers of higher-density materials, arranged parallel to the axis of rotation to absorb vibrations and reduce noise.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If pendulum bodies are used to filter vibrations in a transmission system, then vibration filtering performance is improved, but at low engine speeds the pendulum bodies fall due to gravity and strike surrounding parts generating noise
Solution Approach 1:
The patent applies beforehand cushioning by providing a damping element between the pendulum body and the surrounding part before the impact occurs. This damping element absorbs the impact energy when the pendulum body falls at low speeds, preventing the harmful noise while allowing the pendulum mechanism to function normally at higher speeds.
Solution Approach 2:
The damping element acts as an intermediary between the pendulum body and the surrounding part. It mediates the interaction during impact by absorbing energy, thus preventing direct contact and noise generation while maintaining the functional relationship between the pendulum body and the housing.
2Speed
If the pendulum damping device operates at low engine speeds, then it can handle low-speed vibrations, but centrifugal force becomes less than gravity causing pendulum bodies to fall and strike parts
Solution Approach 1:
The patent converts the harmful gravitational impact at low speeds into a beneficial damping effect. By positioning the damping element to absorb impacts during low-speed operation, the previously harmful gravitational force becomes a controlled energy source that is dissipated usefully rather than creating noise.
3Object-generated harmful factors
If damping elements are added to prevent impacts, then noise is reduced, but device complexity increases
Solution Approach 1:
The damping element is implemented as a flexible component that can be integrated into the existing structure. This flexible element provides the necessary damping function without requiring complex mechanical structures, thus adding minimal complexity while effectively reducing impact noise.
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 dampens vibrations and reduces noise by utilizing the vibration-absorbing properties of the lower-density material, maintaining sufficient mass for oscillation filtration and resistance to centrifugal forces.
Implementation Method 1
at least one of the support, the pendulum body and the rolling element comprises a first and a second material, the second material having a lower density than that of the first material and... the second material be an elastically deformable material, such as an elastomer
Implementation Method 2
the second material be an elastically deformable material, such as an elastomer
Implementation Method 3
the pendulum bodies then tends to fall and strike the surrounding part(s). This occurs particularly during engine shutdown. The impacts excite the intrinsic modes of the parts involved and generate noise. One aim of the invention is to limit such drawbacks
Implementation Method 4
below a certain engine speed, the centrifugal force becomes less than gravity
Implementation Method 5
the first material, it will typically be a metal, such a material providing sufficient mass to the pendulum body to filter oscillations. This material also contributes to the pendulum body's stability under centrifugal stress
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
This is a pendulum damping device (1), comprising a support (2) capable of rotating about an axis of rotation (X), a pendulum body (3) movable relative to the support, and rolling elements (11). At least one of the support, the pendulum body and the rolling element comprises a first and a second material (21,23), the second material (23) having a lower density than that of the first material (21), and, parallel to said axis of rotation (X), said first and second materials are arranged in several layers.