Heavy-Duty Air Spring Damping via Piston Chamber Airflow

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Heavy-duty vehicle air-ride axle/suspension systems with non-damping air springs require additional shock absorbers for damping, increasing weight, complexity, and maintenance costs, while prior art air springs with damping characteristics are limited by custom design requirements and potential issues in low-pressure situations.

Innovation Solution

Converting a non-damping air spring with a 'molded-in' end closure into an air spring with damping characteristics by sealing the piston chamber and providing fluid communication with the bellows chamber, allowing for varying piston and pedestal combinations to optimize damping without custom designs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If non-damping air springs are used in heavy-duty vehicle suspension systems, then the basic suspension function is provided, but additional shock absorbers are required which increase weight, complexity, and maintenance costs

Engineering Contradiction:
Improvedamping functionVSAvoidsuspension system complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent combines the damping function previously provided by separate shock absorbers into the air spring itself by creating a piston chamber with fluid communication between the bellows chamber and piston chamber. This integration eliminates the need for additional shock absorbers while maintaining both suspension and damping functions in a single component.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The air spring is designed to perform multiple functions: suspension (cushioning) through the bellows chamber and damping through the piston chamber with controlled fluid communication. This multi-functional design allows the single air spring component to replace what previously required separate shock absorbers, reducing system complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Adaptability or versatility

If prior art air springs with damping characteristics are used, then damping function is integrated, but custom design requirements limit adaptability and increase manufacturing complexity

Engineering Contradiction:
Improveapplication-specific optimizationVSAvoidcustom design requirements
Core Design Contradiction:
Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

The air spring is divided into distinct functional chambers: the bellows chamber for suspension and the piston chamber for damping. These chambers are connected through controlled fluid communication pathways. This segmentation allows independent optimization of each chamber's volume and characteristics while using standardized manufacturing processes for the overall assembly.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent enables adjustment of damping characteristics by modifying parameters such as the volume of the piston chamber, the cross-sectional area of fluid communication openings, and the positioning of the piston. These parameter changes allow optimization for different applications without requiring complete custom design, as they can be achieved through standardized component variations.

Inventive Principle:
Principle #35Parameter changes

3Ease of manufacture

If 'take-apart' design air springs are used, then assembly is simplified, but limitations in low-pressure situations reduce reliability

Engineering Contradiction:
Improveassembly simplicityVSAvoidlow-pressure performance
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The piston chamber acts as a pre-configured cushioning volume that provides backup support in low-pressure situations. When the bellows chamber pressure is reduced, air can be supplied to the piston chamber through the fluid communication pathways, ensuring continuous damping function and preventing bottoming out, thereby maintaining reliability across all pressure conditions.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

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

Eliminates the need for shock absorbers, reduces weight and maintenance costs, and enables optimized damping characteristics for different applications without custom design and manufacturing processes, while avoiding limitations of 'take-apart' designs.

Implementation Method 1

providing fluid communication between the piston chamber and a bellows chamber of the air spring in order to provide damping characteristics to the air spring

Methodology Applied
Scientific EffectFluid communication:

Data Source

PatentEP3294577B1Air spring with damping characteristics for heavy-duty vehicles
Publication Date: 2024.09.18 HENDRICKSON USA LLC
  • EP3294577B1 patent drawingFigure 1
  • EP3294577B1 patent drawingFigure 2
  • EP3294577B1 patent drawingFigure 3

AI summary

An air spring with damping characteristics for a suspension assembly of a heavy-duty vehicle includes a bellows and a piston. The bellows includes a bellows chamber. The bellows is attached to a main member of the heavy-duty vehicle and to the piston. The piston includes an open bottom that is sealingly closed by a disc attached to the open bottom. The piston and the disc define a piston chamber. The piston is mounted on the suspension assembly of the heavy-duty vehicle. The bellows chamber and the piston chamber are in fluid communication with each other via at least one opening, wherein airflow between the bellows chamber and the piston chamber provides damping to the suspension assembly of the heavy-duty vehicle.