Gerotor Gear Cutout Structure for High-Speed Fluid Flow

Solution Overview

Problem

Gerotor systems face inefficiencies in fluid flow, particularly at high rotational speeds, leading to issues like cavitation, trapped gas, and irregularities such as noise and vibration, which affect their performance and reliability.

Innovation Solution

The implementation of an enhanced gerotor apparatus with features like cutouts and porting flow paths on the inner and outer gears, which enhance fluid communication and flow rates, reducing pressure drops and improving volumetric efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If conventional gerotor design is used, then the structure is simple, but fluid flow efficiency deteriorates at high rotational speeds

Engineering Contradiction:

Improvefluid flow rateVSAvoidcavitation and trapped gas

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The gear teeth are segmented into multiple land portions and groove portions along the circumferential direction. This segmentation creates multiple fluid communication paths between the inlet and outlet, allowing continuous fluid flow even during gear rotation, thereby preventing cavitation and trapped gas formation while maintaining high flow rates

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different portions of the gear teeth have different functions: land portions provide structural support and sealing, while groove portions provide fluid communication pathways. This local differentiation of properties within the gear structure enables simultaneous achievement of mechanical strength and fluid flow efficiency at high rotational speeds

Inventive Principle:

Principle #3Local quality

2Productivity

If conventional gerotor design is used, then manufacturing is simple, but fluid communication efficiency deteriorates

Engineering Contradiction:

Improvevolumetric efficiencyVSAvoidgear structure

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The gear teeth are segmented into multiple land portions and groove portions along the circumferential direction. This segmentation creates multiple fluid communication paths between the inlet and outlet, allowing continuous fluid flow even during gear rotation, thereby preventing cavitation and trapped gas formation while maintaining high flow rates

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different portions of the gear teeth have different functions: land portions provide structural support and sealing, while groove portions provide fluid communication pathways. This local differentiation of properties within the gear structure enables simultaneous achievement of mechanical strength and fluid flow efficiency at high rotational speeds

Inventive Principle:

Principle #3Local quality

3Productivity

If conventional gerotor design is used, then the structure is simple, but pressure drops increase

Engineering Contradiction:

Improveflow rateVSAvoidpressure drop

Core Design Contradiction:

ProductivityVSStress or pressure

Solution Approach 1:

The grooves are configured to extend continuously from the inlet toward the outlet along the gear tooth, ensuring uninterrupted fluid communication throughout the gear rotation cycle. This continuous fluid path eliminates pressure drops and flow interruptions that would otherwise occur during the pumping action, maintaining steady high flow rates

Inventive Principle:

Principle #20Continuity of useful action

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

The enhanced design improves flow rates, reduces cavitation and noise, and enhances the overall performance of gerotor systems, particularly at high rotational speeds, leading to increased reliability and efficiency.

Implementation Method 1

a rotating gear configuration cyclically varies an internal volume to produce continuous fluid intake and fluid discharge actions, which produces a volumetric flow of fluid

Methodology Applied

Scientific EffectVolumetric displacement:

Implementation Method 2

One or more flow-enhancing features are defined by the inner gear, by the outer gear, or both. For example, a cutout may be defined by the inner surface of the outer gear between a neighboring pair of the inward-facing teeth

Methodology Applied

Scientific EffectFluid communication enhancement:

Implementation Method 3

The inner gear and the outer gear reside in contact such that the inner profile of the outer gear seals against the outer profile of the inner gear at multiple distinct points

Methodology Applied

Scientific EffectMechanical sealing:

Data Source

PatentUS10890181B2Enhancing fluid flow in gerotor systems

Publication Date: 2021.01.12 BOUNDARY LUBRICATION SYST LLC

AI summary

In a general aspect, fluid flow in a gerotor system is enhanced. In some cases, a gerotor apparatus includes inner and outer gears. The outer gear includes inward-facing teeth and an inner surface that defines an inner profile of the outer gear. The inner gear includes outward-facing teeth and an outer surface that defines an outer profile of the inner gear. The inner gear and the outer gear reside in contact such that the inner profile of the outer gear seals against the outer profile of the inner gear at multiple distinct points. One or more cutouts are defined by the inner surface of the outer gear between a neighboring pair of the inward-facing teeth, by the outer surface of the inner gear between a neighboring pair of the outward-facing teeth, or both.