Servovalve Valve Body Return Port Layout Against Contamination

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Servovalves in aircraft air management systems face contamination issues due to particulate contaminants entering through the return port, leading to reduced effectiveness, and traditional solutions like filters increase flow resistance.

Innovation Solution

The return port is formed by a third passage that intersects the first passage at an angle, preventing contaminants from entering the valve body and using a second nozzle to reduce cross-sectional flow area, creating a Venturi effect that minimizes contaminant flow into the valve body.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If a filter is provided across the return port to stop contaminants, then contaminant entry is reduced, but flow resistance increases

Engineering Contradiction:
Improvecontaminant entryVSAvoidflow resistance
Core Design Contradiction:
Object-affected harmful factorsVSLoss of energy

Solution Approach 1:

The harmful function of the return port (allowing contaminant entry) is extracted and separated from the main flow path. The return port is repositioned to the side of the valve body, creating an independent contamination exit path that does not interfere with the main fluid flow through the first passage, thus eliminating the need for a filter while preventing contaminant buildup.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The return port is moved from a centralized position to a lateral position on the valve body. This spatial reconfiguration creates a separate dimension for contaminant removal that is independent of the main flow path, allowing contaminants to be discharged without creating flow resistance in the primary fluid pathway.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Device complexity

If the return port is positioned in line with fluid flow direction, then flow path is simple, but contaminant buildup occurs in the valve system

Engineering Contradiction:
Improveflow path configurationVSAvoidcontaminant buildup
Core Design Contradiction:
Device complexityVSObject-affected harmful factors

Solution Approach 1:

The flow path is segmented into distinct functional zones: the first passage for main fluid flow, the second passage for control flow, and the third passage (return port) for contaminant discharge. This segmentation allows each passage to be optimized for its specific function, with the return port positioned independently to prevent contaminant interference with the main flow path.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The return port is repositioned from a linear alignment with the main flow to a lateral position on the valve body. This dimensional change creates spatial separation between the contaminant discharge path and the main fluid flow path, enabling simple flow path configuration while simultaneously preventing contaminant buildup in the valve system.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Reliability

If a filter is installed to prevent contaminant entry, then valve effectiveness is maintained, but flow resistance increases reducing efficacy

Engineering Contradiction:
Improvevalve effectivenessVSAvoidflow efficiency
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The harmful function of contaminant entry through the return port is extracted and isolated. By repositioning the return port to the side of the valve body and creating a separate discharge path via the third passage, contaminants are removed from the system without requiring a filter, thus maintaining valve effectiveness while preserving flow efficiency.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The third passage acts as an intermediary channel that facilitates contaminant removal from the valve system. This intermediate structure provides a dedicated pathway for contaminant discharge that does not interfere with the main fluid flow, thereby maintaining both valve effectiveness and flow efficiency without requiring additional filtering components.

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 design effectively reduces contaminant buildup within the servovalve, maintaining its operational effectiveness without increasing flow resistance, as contaminants are diverted out of the valve body and the Venturi effect enhances fluid flow velocity, reducing pressure and contaminant entry.

Implementation Method 1

the return port is formed by a first open end of a third passage which extends through the valve body and will intersect the first passage at an angle. Thus, any contaminants entering the return port will be unlikely to flow into the first passage from the third passage

Methodology Applied
Scientific EffectFluid flow direction control through geometric configuration:

Implementation Method 2

using a second nozzle to reduce cross-sectional flow area, creating a Venturi effect that minimizes contaminant flow into the valve body

Methodology Applied
Scientific EffectVenturi effect: Venturi Effect

Data Source

PatentEP3536980B1Valve body for a servovalve
Publication Date: 2022.12.28 HAMILTON SUNDSTRAND CORP
  • EP3536980B1 patent drawingFigure 1
  • EP3536980B1 patent drawingFigure 2
  • EP3536980B1 patent drawingFigure 3

AI summary

A valve body (205) for a servovalve (200) is provided, the valve body (205) comprising: a first surface (208); a second surface (210) offset from the first surface (208); a first passage (222) extending through the body between the first and second surfaces from a first side (212) of the body to a second side (214) thereof; a second passage (220) extending from the first surface (208) towards the second surface (210) and intersecting the first passage (222); a supply port (226) joined with the first passage (222); a control port (224) joined with the first passage (222); a return port (274) joined with the first passage (222), wherein the return port (274) comprises a third passage (278) extending through the body between the first and second surfaces from a third side (266) of the body to a fourth side (268) thereof and intersecting with the first passage (222).