Oil Degradation Detection via Electric Pump Current Comparison

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current methods for determining engine oil degradation either rely on travel distance or physical property sensors, which are either inaccurate or costly and complex.

Innovation Solution

An oil-degradation determination apparatus that measures and compares the electric current or revolution speed of an electric oil pump at constant conditions before and after a predetermined time, determining viscosity degradation without the need for direct oil sensors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a sensor is used to directly detect the viscosity or other parameters of the oil, then the measurement precision of oil degradation is improved, but the device complexity and cost increase

Engineering Contradiction:

Improveoil degradation detection accuracyVSAvoidsensor system complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent uses the electric pump as an intermediary device to indirectly measure oil viscosity. Instead of placing sensors directly in the oil, the system measures the electric current or revolution speed of the pump, which changes in response to oil viscosity changes. This intermediary approach achieves accurate measurement while avoiding direct contact sensors in the oil system.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent replaces direct mechanical/physical sensing of oil properties with an electrical measurement system. By measuring electrical parameters (current, voltage, frequency, or revolution speed) of the pump motor, the system substitutes complex mechanical viscosity sensors with simpler electrical measurement circuits.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Measurement precision

If physical property sensors are used to detect oil condition, then the measurement precision is improved, but the ease of manufacture and cost worsen

Engineering Contradiction:

Improveoil condition detection accuracyVSAvoidsystem manufacturing simplicity

Core Design Contradiction:

Measurement precisionVSEase of manufacture

Solution Approach 1:

The patent makes the existing electric pump serve a dual function: both circulating the oil and acting as the measurement device for oil degradation. The pump's own electrical characteristics are used to detect viscosity changes, eliminating the need for separate sensing systems and reducing manufacturing complexity.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The electric pump is given multiple functions: it continues to perform its primary role of circulating oil while simultaneously serving as the sensor for detecting oil viscosity degradation. This multi-functionality reduces the total number of components needed and simplifies the overall system.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Ease of operation

If travel distance integration method is used to determine oil change timing, then the ease of operation is improved, but the measurement precision of actual oil degradation worsens

Engineering Contradiction:

Improveoil change scheduling simplicityVSAvoidactual oil degradation accuracy

Core Design Contradiction:

Ease of operationVSMeasurement precision

Solution Approach 1:

The patent implements a feedback mechanism that continuously monitors the actual condition of the oil through pump electrical characteristics and uses this information to determine when oil change is needed. This feedback-based approach replaces fixed schedule methods with condition-based monitoring, improving accuracy while maintaining operational simplicity.

Inventive Principle:

Principle #23Feedback

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

Enables accurate and cost-effective determination of engine oil viscosity degradation, simplifying the system and eliminating the need for physical property sensors, allowing for timely oil changes based on actual usage conditions.

Implementation Method 1

an electric pump (41) that circulates oil in an engine (10)

Methodology Applied

Scientific EffectElectromagnetic conversion: Electromagnetic Induction

Implementation Method 2

measuring a first electric-current value of a driving current used to operate an electric oil pump (41) at a predetermined constant revolution

Methodology Applied

Scientific EffectElectrical measurement: Ohm's Law

Data Source

PatentUS8342013B2Oil-degradation determination apparatus

Publication Date: 2013.01.01 HONDA MOTOR CO LTD

AI summary

A method and apparatus for determining oil degradation measures a first electric-current value of a driving current used to operate an electric oil pump at a predetermined consistent revolution, and stores the first electric-current value as an electric-current initial value. Data is corrected by measuring a second electric-current value of the driving current, with the second electric-current value being measured when the electric pump is operated at the predetermined consistent revolution when the engine is driven a predetermined time after the electric-current initial value is stored. The electric-current initial value is compared with the second electric-current value. It is then determined that a viscosity of the oil has become low when a difference between the electric-current initial value and the second electric-current value is equal to or greater than a predetermined value.