Hydraulic Suspension Energy Management via Flow Recirculation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Hydraulic suspension systems face inefficiencies due to discontinuity in load exertion and energy consumption when actuator flow is re-circulated between chambers, leading to noise and parasitic losses, and the need for synchronization between pressure control and directional control valves in dis-continuous systems, while continuous systems consume energy when actuator flow is not re-circulated.

Innovation Solution

A hydraulic suspension system that includes a valve control mechanism allowing re-circulation of actuator flow from one chamber to its opposite side during resistive mode, using a regulated pressure source with pressure reducing means and hydro-piloted valves with integrated check valves to manage pressure differences and optimize energy usage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stress or pressure

If a pressure control valve regulates controlled pressure by throttling pump flow to tank in a dis-continuous system, then the controlled pressure is maintained, but power is still consumed by the system and energy is wasted

Engineering Contradiction:
Improvecontrolled pressureVSAvoidpower consumption
Core Design Contradiction:
Stress or pressureVSUse of energy by moving object

Solution Approach 1:

The patent introduces a flow divider as an intermediary device that splits the pump flow into two separate circuits, each with its own pressure control valve. This allows independent pressure control in each circuit while maintaining system efficiency by directing flow only where needed, rather than throttling all pump flow through a single valve.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The hydraulic suspension system is divided into separate circuits (front and rear) with individual pressure control valves. This segmentation allows each circuit to be controlled independently, reducing the need for continuous throttling and improving overall energy efficiency by isolating pressure control functions.

Inventive Principle:
Principle #1Segmentation

2Stress or pressure

If the pressure control valve has a minimum controlled pressure relative to tank pressure, then pressure regulation is achieved, but discontinuity in load and flow occurs with possible noise issues

Engineering Contradiction:
Improveminimum controlled pressureVSAvoiddiscontinuity and noise
Core Design Contradiction:
Stress or pressureVSObject-generated harmful factors

Solution Approach 1:

The flow divider acts as an intermediary that separates the hydraulic circuits, allowing each pressure control valve to operate independently. This separation minimizes the impact of minimum pressure thresholds on overall system continuity, as one circuit can maintain pressure while the other adjusts, reducing load discontinuities and noise.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Stability of the object's composition

If actuator flow is re-circulated from one chamber to the opposite chamber in resistive mode, then flow continuity is maintained, but energy is consumed within the system

Engineering Contradiction:
Improveflow continuityVSAvoidenergy consumption
Core Design Contradiction:
Stability of the object's compositionVSLoss of energy

Solution Approach 1:

The patent extracts the high-pressure flow from the resistive chamber and directs it separately through the flow divider to the tank or to the motoring chamber, rather than forcing recirculation through the pressure control valve. This extraction approach maintains flow continuity while reducing energy consumption by avoiding unnecessary throttling of the high-pressure flow.

Inventive Principle:
Principle #2Taking out (Extraction)

4Device complexity

If pump flow is shared between front and rear systems using a flow divider, then system duplication is reduced, but parasitic losses occur in the valve arrangement

Engineering Contradiction:
Improvesystem duplicationVSAvoidparasitic losses
Core Design Contradiction:
Device complexityVSLoss of energy

Solution Approach 1:

The flow divider serves as an intermediary that efficiently splits pump flow between front and rear circuits with minimal parasitic losses. By positioning the flow divider at the pump outlet and using direct hydraulic paths to each circuit, the system reduces energy losses compared to alternative valve arrangements that would require additional throttling and redirection of flow.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 solution enables continuous suspension with reduced energy consumption, allowing for a smaller pump capacity, lower weight, cost, and emissions, and the use of an electro-hydraulic pump independent of the engine, with energy storage during non-motoring modes, enhancing system flexibility and performance.

Implementation Method 1

using a regulated pressure source with pressure reducing means and hydro-piloted valves with integrated check valves to manage pressure differences

Methodology Applied
Scientific EffectPressure difference: Pressure Gradient

Implementation Method 2

pressure reducing means to regulate actuator chambers

Methodology Applied
Scientific EffectPressure reduction: Pressure Drop

Implementation Method 3

hydro-piloted valves with integrated check valves

Methodology Applied
Scientific EffectCheck valve flow control: Valve

Data Source

PatentEP2890573B1Hydraulic suspension system
Publication Date: 2017.08.16 BEIJING WEST IND CO LTD
  • EP2890573B1 patent drawingFigure 1A~1C
  • EP2890573B1 patent drawingFigure 2A~2C
  • EP2890573B1 patent drawingFigure 3A~3B

AI summary

Provided is a continuous hydraulic suspension system which has, in each front and rear valve block (25, 26), an Energy Management Valve (EMV) (27, 28) and Check Valves (CV) (29, 30, 31, 32) to provide re-circulation of oil in the resistive mode. The system allows reduced energy consumption during non-motoring modes, and enables a smaller capacity pump and/or an electric motor pump to be used.