Liquid-Sealed Vibration Isolator Partition Element Design
Solution Overview
Problem
Existing liquid-sealed antivibration devices face challenges in reducing dynamic spring constant for minute amplitude vibrations while maintaining high damping performance for large amplitude vibrations, which affects noise suppression and riding comfort.
Innovation Solution
The device incorporates a partition element with an annular orifice forming member, an elastic wall, and a pair of partition plates that connect via a center portion, featuring through holes and gaps allowing liquid flow between chambers at neutral positions, and blocking liquid flow during axial displacement to restrict vibrations and enhance damping.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the partition element uses a conventional structure with an elastic wall and partition plates, then damping performance for large amplitude vibrations is secured, but dynamic spring constant cannot be sufficiently reduced for minute amplitude vibrations
Solution Approach 1:
The partition element is segmented into multiple functional components: an elastic wall for damping, partition plates for blocking, and a connecting portion with through-holes for frequency-dependent flow control. This segmentation allows each component to specialize in specific vibration frequency ranges, resolving the contradiction between damping large vibrations and reducing spring constant for small vibrations.
Solution Approach 2:
The system transitions from a static partition structure to a dynamic one where the connecting portion with through-holes actively modulates liquid flow based on vibration frequency. At low frequencies, liquid flows through the orifice flow passage for damping; at high frequencies, the structure enables reciprocating movement that reduces dynamic spring constant, achieving adaptive behavior across different operating conditions.
2Loss of energy
If the partition element restricts liquid flow between chambers, then damping performance improves for large amplitude vibrations, but noise suppression performance deteriorates for high frequency vibrations
Solution Approach 1:
The system changes the flow parameters of liquid between chambers based on vibration frequency. The connecting portion with through-holes and gaps creates different flow resistance characteristics: high resistance at low frequencies for damping, and controlled flow paths at high frequencies for noise suppression. This parameter change resolves the contradiction between damping and noise suppression.
3Force
If the partition element allows liquid flow between chambers, then dynamic spring constant reduces for high frequency vibrations, but damping performance deteriorates for low frequency vibrations
Solution Approach 1:
Different regions of the partition element have different flow control qualities: the orifice flow passage provides high resistance for damping at low frequencies, while the connecting portion with through-holes and gaps provides controlled flow paths for reducing spring constant at high frequencies. This local quality differentiation resolves the contradiction between damping and dynamic spring constant reduction.
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 effectively reduces dynamic spring constant for high-frequency vibrations, improving noise suppression while maintaining high damping performance for low-frequency vibrations, thus enhancing both noise reduction and riding comfort.
Implementation Method 1
an elastic wall which blocks a space formed within an inner peripheral surface of the orifice forming member and is made of a rubbery elastic material
Implementation Method 2
vibrations can be reduced by making use of the reduction of a dynamic spring constant generated by the reciprocating movement of the partition plates
Implementation Method 3
damping vibrations by making use of a liquid flow effect generated by an orifice flow passage with respect to large amplitude vibrations in a low frequency range
Implementation Method 4
an orifice flow passage which allows the first liquid chamber and the second liquid chamber to be communicated with each other
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
A partition element 40 which partitions a first liquid chamber 36A and a second liquid chamber 36B is constituted of an annular orifice forming member 44, an elastic wall which blocks a space formed within an inner peripheral wall 44A, and a pair of partition plates 48, 50 which sandwiches the elastic wall. A through hole 74 is formed in an elastic wall portion of the elastic wall 46 which is sandwiched by the partition plates 48, 50. Gaps 78 which are connected with the through hole 74 are formed between wall surfaces of the elastic wall 46 and plate surfaces of the partition plates 48, 50, and a first liquid chamber 36A and a second liquid chamber 36B are connected with each other by way of the through hole 74 and the gaps 78 in a state where a liquid is allowed to flow between these liquid chambers when the partition plates 48, 50 are at a neutral position, and the through hole 74 is blocked by partition plates 48, 50 due to the displacement of the partition plates 48, 50.