Torque Rod Bushing Structure for Lower Vertical Vibration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional torque rods experience rigid body resonance, leading to high vibration transmission characteristics in the up-down direction, which affects interior sound levels and ride comfort, and existing solutions either increase weight or have reached technical maturity.
Innovation Solution
A torque rod design with a first coupling section having a smaller spring constant in the Z-axis direction and a second coupling section, where the elastic member is twisted, reducing vibration transmission characteristics without increasing weight by optimizing the cross-sectional area and thickness of the elastic member.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If mass is added to the end of the torque rod to lower the rigid body resonance frequency, then the vibration transmission characteristics in the frequency range having high sensitivity to the vehicle body is lowered, but the weight of the vehicle increases
Solution Approach 1:
The elastic member is designed with non-uniform cross-sectional area along its longitudinal direction, creating different local stiffness characteristics. The cross-sectional area varies to achieve different spring constants in different regions, allowing vibration isolation without adding weight. This local variation in geometry optimizes the vibration transmission characteristics while maintaining weight efficiency.
Solution Approach 2:
The spring constant of the elastic member is modified by changing its geometric parameters, specifically the cross-sectional area and thickness. By adjusting these parameters, the rigid body resonance frequency is shifted to a lower frequency, and the vibration transmission characteristics are reduced in the sensitive frequency range without requiring additional mass.
2Object-affected harmful factors
If the spring constant in the up-down direction of the large round section is reduced, then the vibration transmission characteristics are lowered, but the technical development has reached maturity with no significant improvement expected
Solution Approach 1:
Instead of only modifying the spring constant in the vertical direction, the invention introduces a new dimension of control by varying the cross-sectional area along the longitudinal direction of the elastic member. This creates additional degrees of freedom in designing the vibration isolation characteristics, opening new technical development possibilities beyond the conventional approach.
Solution Approach 2:
The elastic member combines different geometric configurations along its length, creating a composite structure with varying stiffness properties. This composite design allows for optimized vibration isolation performance while maintaining technical adaptability and potential for further development.
3Object-affected harmful factors
If a peak frequency of the rigid body resonance is shifted to a lower frequency, then the vibration transmission characteristics in the frequency range having high sensitivity to the vehicle body is lowered, but conventional methods either increase weight or have reached technical maturity
Solution Approach 1:
The geometric parameters of the elastic member, particularly the cross-sectional area and thickness, are optimized to shift the rigid body resonance frequency to a lower value. This parameter optimization achieves vibration isolation in the sensitive frequency range without requiring additional mass, thereby resolving the contradiction between vibration reduction and weight control.
Solution Approach 2:
The elastic member features localized variations in cross-sectional area that create specific stiffness characteristics. These local quality variations enable the system to achieve desired vibration isolation performance through geometric optimization rather than mass addition.
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 design effectively lowers vibration transmission characteristics and shifts the rigid body resonance frequency, improving ride comfort and reducing noise without adding weight, by utilizing a smaller spring constant in the Z-axis direction and torsional spring constant.
Implementation Method 1
an elastic member to elastically join the outer member with the inner member
Implementation Method 2
The elastic member has a spring constant in a Z-axis direction orthogonal to the X-axis direction and the Y-axis direction smaller than a spring constant in the X-axis direction
Implementation Method 3
when the vibration in the up-down direction is transmitted from the first coupling section to the second coupling section, the elastic member of the first coupling section is twisted around the first center axis. In this case, a torsional spring constant of the elastic member is also resulted in being small
Data Source
AI summary
A torque rod includes: a rod body; a first coupling section provided at one end in an X-axis direction as a longitudinal direction of the rod body and having a first center axis along a Y-axis direction orthogonal to the X-axis direction; and a second coupling section provided at the other end in the X-axis direction of the rod body and being larger than the first coupling section. The first coupling section includes: an outer member having a cylinder shape connected to the rod body; an inner member provided in the center of the outer member; and an elastic member to elastically join the outer member with the inner member, and the elastic member has a spring constant in a Z-axis direction orthogonal to the X-axis direction and the Y-axis direction smaller than a spring constant in the X-axis direction.