Piston Lip and Recess Structure for Vane Pump Contaminant Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In vane pumps and compressors, contaminants are often forced into the space between the piston and sleeve due to fluid pressure and forces, leading to undesirable valve seizure.

Innovation Solution

A piston with a radially outer lip and a recess on its forward portion is designed, reducing the axial component of fluid flow and directing it radially outward, minimizing contaminant entry between the piston and sleeve surfaces.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a flat or nosed piston face is used, then the valve can regulate pressure effectively, but contaminants are forced into the space between the piston and sleeve causing valve seizure

Engineering Contradiction:

Improvevalve operation reliabilityVSAvoidcontaminant entry causing seizure

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The piston face is designed with a curved surface instead of a flat or nosed face. This curvature changes the fluid flow pattern, directing it radially outward rather than axially forward, which prevents contaminants from being forced into the clearance space between the piston and sleeve.

Inventive Principle:

Principle #14Spheroidality (Curvature)

Solution Approach 2:

The piston design incorporates different surface characteristics in different regions: a curved forward face for fluid direction control, a lip at the periphery to seal the clearance space, and a recess to manage fluid flow. Each region has a specific function that collectively prevents contaminant intrusion while maintaining pressure regulation.

Inventive Principle:

Principle #3Local quality

2Stress or pressure

If pressure delta and fluid forces are used to move the vane, then the valve can regulate under vane pressure, but contaminants are forced into the piston-sleeve space

Engineering Contradiction:

Improveunder vane pressure regulationVSAvoidcontaminant intrusion

Core Design Contradiction:

Stress or pressureVSObject-affected harmful factors

Solution Approach 1:

The curved piston face redirects the fluid flow generated by pressure delta and fluid forces. Instead of allowing this pressurized fluid to push contaminants axially into the clearance space, the curvature directs the flow radially outward, maintaining pressure regulation functionality while eliminating the harmful contaminant transport mechanism.

Inventive Principle:

Principle #14Spheroidality (Curvature)

Solution Approach 2:

The design converts the potentially harmful effect of pressurized fluid carrying contaminants into a beneficial flow pattern. The curved surface and lip structure guide the pressurized fluid to flow in a controlled radial direction, using the same pressure forces that were previously problematic to achieve clean, controlled fluid movement that protects the clearance space.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

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 significantly reduces the likelihood of contaminants entering the space between the piston and sleeve, preventing valve seizure and improving fluid flow efficiency.

Implementation Method 1

Methodology Applied

Scientific EffectFluid flow direction control:

Data Source

PatentUS10088057B2Under vane valve piston structure

Publication Date: 2018.10.02 HAMILTON SUNDSTRAND CORP

AI summary

A valve has a sleeve with at least one outlet port in a radially outer surface. A piston is moveable within the sleeve along an axis. The piston has a lip on a radially outer portion extending forwardly to an axially forward most end and a recess radially inward from the lip with respect to an axis of the piston. A vane pump is also disclosed.