Pendulum Damper Bearing Geometry to Eliminate Raceway Sliding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Pendulum damping devices in motor vehicle transmission systems face performance degradation due to sliding issues, which affect their ability to filter vibrations effectively, especially when pendulum bodies move in combined translation and rotation movements.
Innovation Solution
The design incorporates a rolling member with specific cylindrical portions of different radii, allowing it to roll on fractions of rolling tracks with optimized ratios, ensuring the contact angle remains below the friction cone angle, thereby reducing or eliminating sliding. This is achieved by choosing appropriate radii values for the first, second, third, and fourth radii, which define a third gear that minimizes sliding during movement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the rolling element uses cylindrical portions of different radii to guide combined movement of the pendulum body, then the pendulum can achieve both translational and rotational movement, but slippage occurs in the rolling elements which degrades filtering performance
Solution Approach 1:
The patent applies parameter changes by optimizing the ratio between the radii of the rolling element portions and the rolling tracks. Specifically, the ratio between the outer radius of the rolling element and the radius of the rolling track is designed to be between 0.5 and 1.5, which ensures that the contact angle remains below the friction cone angle throughout the combined movement, thereby eliminating slippage while maintaining the desired movement capability
Solution Approach 2:
The patent implements dynamics by allowing the pendulum body to perform combined movement (translation plus rotation) relative to the support. The rolling element guides this dynamic movement through its interaction with the rolling tracks, enabling the system to adapt to varying operational conditions while maintaining reliable rolling contact through proper radius ratio design
2Ease of operation
If the contact angle of the rolling element exceeds the friction cone angle, then the rolling element can accommodate larger movements, but slippage occurs which reduces filtering effectiveness
Solution Approach 1:
The patent changes the critical parameter of the contact angle by optimizing the radius ratio between the rolling element and rolling track. By ensuring the ratio is between 0.5 and 1.5, the contact angle is kept below the friction cone angle, preventing slippage and energy loss while still allowing sufficient movement range for effective vibration filtering
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 reduces or eliminates sliding, maintaining contact angles below the friction cone angle, thus enhancing the filtering performance of pendulum damping devices by ensuring continuous, friction-free movement, even during combined movements.
Implementation Method 1
during at least part of its movement, the rolling element rolling simultaneously on a pair of fractions of rolling tracks
Implementation Method 2
The ratio between the second ratio and the first ratio defines a third ratio for said pair of raceway fractions, this third ratio being chosen so as to reduce, in particular eliminate, the slippage of the rolling element
Data Source
Figure 1~2
Figure 3
AI summary
The invention relates to a pendulum damping device (1), which comprises: a mounting (2) capable of rotating about an axis (X); at least one pendulum body (3), movable relative to the mounting (2); and at least one antifriction bearing (11), the antifriction bearing (11) comprising, in order to guide the movement of the pendulum body (3) relative to the mounting: a first cylindrical portion (20) with a first radius (R1) engaging with at least one first raceway (12) rigidly connected to the mounting (2); and a second cylindrical portion (21) with a second radius (R2) engaging with a second raceway (13) rigidly connected to the pendulum body (3), the ratio (η1) between the second radius (R2) and the first radius (R1) defining a first ratio, during at least one portion of the movement thereof, the antifriction bearing (11) simultaneously rolling over a couple of fractions of the raceways (12, 13), formed by a fraction of the second raceway (13) with a third radius (R3) and a fraction of the first raceway (12) with a fourth radius (R4), the ratio (η2) between the third radius (R3) and the fourth radius (R4) defining a second ratio for said couple of fractions of raceways, the ratio (η3) between the second ratio (η2) and the first ratio (η1) defining a third ratio for said couple of fractions of raceways, said third ratio (η3) being selected so as to reduce, and in particular to remove, the sliding of the antifriction bearing (11) when it rolls over said couple of fractions of raceways.