Pendulum Powerplant Mount Layout for Engine Vibration Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing pendulum type mount systems for powerplant units on vehicles do not effectively suppress vibrations and noises caused by internal combustion engines, despite using insulators in engine mounts and torque rods.
Innovation Solution
A pendulum type mount system with a pair of first and second lower torque rods, where the first torque rod has a higher spring constant than the second, and both are positioned on opposite sides of the powerplant unit's gravity center, with the first torque rod having stoppers to restrict swinging strokes and the second torque rod maintaining a lower spring constant to distribute reactive torques effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single lower torque rod is used in the pendulum type mount system, then the structure is simple, but the vibration suppression performance is insufficient and the layout flexibility is limited
Solution Approach 1:
The single lower torque rod is divided into two separate torque rods (first and second lower torque rods) positioned on opposite sides of the powerplant unit. This segmentation allows each rod to independently manage vibration characteristics, improving overall vibration suppression performance while maintaining structural simplicity through modular design
Solution Approach 2:
The first and second lower torque rods are equipped with different spring constants tailored to their specific positions and vibration control needs. The first torque rod has a higher spring constant for rigid support, while the second has a lower spring constant for flexible vibration isolation, optimizing local vibration suppression characteristics
2Reliability
If the spring constant of lower torque rods is increased to suppress vibrations, then vibration suppression improves, but the total spring constant increases causing excessive rigidity and reduced layout flexibility
Solution Approach 1:
Different spring constants are assigned to the first and second lower torque rods based on their specific positions and vibration control requirements. This localized differentiation allows high vibration suppression performance through higher spring constants where needed, while maintaining layout flexibility through lower spring constants in other positions
Solution Approach 2:
The asymmetric configuration of the first and second lower torque rods with different spring constants creates an unbalanced but optimized vibration control system. This asymmetry allows the system to achieve superior vibration suppression without excessive overall rigidity, as each rod contributes differently to the total stiffness
3Reliability
If the lower torque rods are positioned closer to the powerplant unit, then the vibration control effectiveness increases, but the contact with surrounding components increases
Solution Approach 1:
The first and second lower torque rods are positioned on opposite sides of the powerplant unit, utilizing the lateral dimension to distribute spacing. This dimensional arrangement maintains effective vibration control through proximity to the powerplant unit while reducing contact with surrounding components by spreading the rods apart in the lateral direction
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
This configuration efficiently suppresses vibrations and noises by distributing reactive torques and maintaining a low total spring constant, enhancing vibration suppression and layout flexibility while reducing contact with surrounding components.
Implementation Method 1
A first spring constant of the first lower torque rod is not smaller than a second spring constant of the second lower torque rod
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
A pendulum type mount system includes a pair of upper mounts (2UR, 2UL) that mount upper portions of a powerplant unit (1) on a vehicle body, and a pair of first and second lower torque rods (2L1, 2L2). The first and second lower torque rods (2L1, 2L2) are located on opposite sides to each other with respect to a reference plane (PR) including a gravity center (G) of the powerplant unit (1). A first spring constant (K1) of the first lower torque rod (2L1) is not smaller than a second spring constant (K2) of the second lower torque rod (2L2). A distance (D1) between a first plane (P1) including the first lower torque rod (2L1) and the reference plane (PR) is not larger than a distance (D2) between a second plane P1 including the second lower torque rod (2L2) and the reference plane (PR).