Fuel Tank Rubber Cushion with Divided Cylinders for Vibration Damping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional tank rubber cushions face challenges in achieving sufficient vertical rigidity and low horizontal spring characteristics without structural complexity or increased components, leading to inadequate vibration damping and noise attenuation.
Innovation Solution
A tank rubber cushion design featuring divided rubber cylinders with axial and transaxial vibration-damping rubber portions, including concave/convex portions, is used to create a compression spring effect in the vertical direction and a shearing spring effect in the horizontal direction, ensuring high load-bearing capacity and noise reduction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If conventional tank rubber cushion structure is used with elastic protrusions, then the structure is simple, but it cannot achieve sufficient vertical rigidity and low horizontal spring characteristics simultaneously
Solution Approach 1:
The rubber cushion is divided into multiple functional regions: an axial vibration-damping rubber portion and a transaxial vibration-damping rubber portion. This segmentation allows each region to specialize in damping vibrations in its respective direction, achieving both vertical rigidity and horizontal flexibility without adding structural complexity
Solution Approach 2:
Different regions of the rubber cushion are given different functional properties. The axial portion is designed to provide rigidity and compression damping, while the transaxial portion is designed with concave/convex portions to provide low spring characteristics and shear damping. This local differentiation resolves the contradiction by making each part optimized for its specific directional requirement
2Reliability
If conventional tank rubber cushion structure is used with elastic protrusions, then the structure is simple, but it cannot achieve effective vibration damping performance
Solution Approach 1:
The vibration damping function is segmented into axial and transaxial portions, each handling specific vibration modes. This segmentation improves overall vibration damping reliability without requiring complex additional components
Solution Approach 2:
The rubber material's physical parameters are optimized differently in axial and transaxial directions through the structural design. The axial portion uses compression deformation characteristics while the transaxial portion utilizes shear deformation, effectively damping vibrations in both directions through parameter differentiation rather than structural complexity
3Force
If conventional tank rubber cushion structure is used, then manufacturing is simple, but it cannot achieve sufficient load bearing capacity
Solution Approach 1:
The axial vibration-damping rubber portion is specifically designed to bear vertical loads through compression, while the transaxial portion handles lateral movements. This local functional differentiation increases load bearing capacity without complicating the overall manufacturing process, as it remains a single integrated rubber component
4Object-generated harmful factors
If conventional tank rubber cushion structure is used, then the structure is compact, but it cannot achieve effective noise attenuation
Solution Approach 1:
The transaxial vibration-damping rubber portion with concave/convex portions is specifically designed to attenuate noise by damping lateral vibrations and fuel movements. This localized noise attenuation feature is integrated into the cushion structure without adding separate noise control components
Solution Approach 2:
The noise attenuation function is separated into the transaxial vibration-damping portion, which specifically targets flow noise through shear deformation. This segmentation allows effective noise control without requiring additional noise reduction devices
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 design achieves effective vibration damping and noise attenuation by providing a hard spring in the vertical direction and a soft spring in the horizontal direction, enhancing durability and manufacturing simplicity while reducing vehicle weight.
Implementation Method 1
the axial vibration-damping rubber portions of the divided rubber cylinders are tucked between the flanges so that a compression spring component gives a dominant effect to the divided rubber cylinder in the axial direction
Implementation Method 2
an axial vibration-damping rubber portion in an annular form being provided on an axially outside portion of each of the divided rubber cylinders
Implementation Method 3
a transaxial vibration-damping rubber portion in a cylinder form being provided to an axially inside portion of each of the divided rubber cylinders, and being thrust into the mounting hole of the support portion from both sides in the axial direction
Implementation Method 4
a transaxial vibration-damping rubber portion in a cylinder form being provided to an axially inside portion of each of the divided rubber cylinders
Implementation Method 5
the transaxial vibration-damping rubber portion of each divided rubber cylinder includes a concave/convex portion wherein a diameter varies in a circumferential direction so that an assembly can be made with a gap between an outer periphery of the inner axial member and an inner periphery of the support portion along the concave/convex portion
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
A tank rubber cushion (10) for providing a vibration-damping support of a fuel tank against a vehicle body, including two divided rubber cylinders (14a,14b) inserted onto an inner axial member (12) having flanges (28,38) at both axial ends and to be inserted through a mounting hole (20) formed in a support portion (18) of the fuel tank. Each of the divided rubber cylinders (14a,14b) is provided with an axial vibration-damping rubber portion (40a,40b) arranged between opposing surfaces of the flange (28,38) of the inner axial member (12) and the support portion (18) in an axial direction, and a transaxial vibration-damping rubber portion (42a,42b) arranged between opposing surfaces of the inner axial member (12) and the support portion (18) in a transaxial direction. The transaxial vibration-damping rubber portion (42a,42b) includes a concave/convex portion (48,50) wherein a diameter varies in a circumferential direction so that an assembly can be made with a gap (52,54) between the inner axial member (12) and the support portion (18).