EGR Valve Status Detection via Inlet Manifold Temperature Velocity

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for determining the operational status of exhaust gas recirculation (EGR) valves in internal combustion engines are costly and prone to malfunction, necessitating a more robust and cost-effective approach.

Innovation Solution

A method involving controlling the EGR valve to transition between closed and open positions, measuring temperature variations at the inlet manifold, and determining a velocity value indicative of temperature change to assess the valve's operational status by comparing it to a predetermined threshold, thereby reducing reliance on expensive sensors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If EGR flow sensors are used to determine the operational status of the EGR valve, then measurement precision is improved, but device complexity and cost increase

Engineering Contradiction:
Improveoperational status detection accuracyVSAvoidsensor system complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent extracts the operational status determination function from the complex EGR flow sensor system and implements it using simple temperature measurements already available in the engine system. By taking out the detection function and implementing it through existing temperature sensors and control logic, the system achieves operational status monitoring without requiring additional expensive flow sensors.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The EGR system uses its own operational parameters (temperature changes in the inlet manifold) to determine its own status. The control unit monitors temperature variations during EGR valve actuation and uses this self-generated data to assess whether the valve is functioning properly, eliminating the need for external sensing devices.

Inventive Principle:
Principle #25Self-service

2Measurement precision

If EGR flow sensors are installed to monitor exhaust gas flow, then measurement precision is improved, but reliability decreases due to potential sensor malfunction

Engineering Contradiction:
Improveexhaust gas flow measurementVSAvoidsensor system reliability
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The patent replaces expensive, complex, and potentially faulty flow sensors with a simple, robust temperature measurement system. The temperature sensors already present in the engine are used to monitor EGR valve operation, creating a fail-safe system that is less prone to malfunction and more reliable in harsh exhaust environments.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The patent substitutes the mechanical/electronic flow sensing system with a thermal measurement approach. Instead of using sensors to directly detect exhaust gas flow, the system uses temperature changes in the inlet manifold as a proxy indicator, replacing complex sensor technology with a simpler thermal measurement method.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Measurement precision

If the EGR valve is controlled to transition between closed and open positions for status determination, then measurement precision is improved through temperature variation detection, but use of energy increases

Engineering Contradiction:
Improvetemperature variation measurementVSAvoidEGR valve actuation energy
Core Design Contradiction:
Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent employs periodic actuation of the EGR valve between closed and open positions to elicit temperature responses. By cycling the valve through controlled states and measuring the resulting temperature variations, the system obtains precise operational status information without requiring continuous high-energy consumption, utilizing instead brief, controlled actuation cycles.

Inventive Principle:
Principle #19Periodic 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

This method provides a rapid and robust means to determine EGR valve functionality, ensuring sufficient exhaust gas flow and reducing the need for additional sensors, while identifying potential malfunctions.

Implementation Method 1

obtaining a signal indicative of a variation of temperature level of the gas present in the inlet manifold

Methodology Applied
Scientific EffectTemperature measurement:

Implementation Method 2

the EGR valve being configured to control a flow of combusted exhaust gas from an exhaust manifold to an inlet manifold

Methodology Applied
Scientific EffectGas flow control:

Implementation Method 3

the relatively warm exhaust gas is, in combination with ambient air, supplied to the combustion cylinders

Methodology Applied
Scientific EffectThermal heating: Heating

Data Source

PatentEP4015806B1A method of determining an operational status of an EGR valve
Publication Date: 2024.11.20 VOLVO TRUCK CORP
  • EP4015806B1 patent drawingFigure 1
  • EP4015806B1 patent drawingFigure 2~4
  • EP4015806B1 patent drawingFigure 5

AI summary

The present disclosure relates to a method of determining an operational status of an exhaust gas recirculation (EGR) valve of an internal combustion engine (ICE) arrangement, the EGR valve being configured to control a flow of combusted exhaust gas from an exhaust manifold to an inlet manifold of the ICE arrangement, the method comprising controlling the EGR valve to transition from a closed position; obtaining a signal indicative of a variation of temperature level of the gas present in the inlet manifold at a duration between a first point in time and a second point in time when the EGR valve assumes the open position; determining, based on the signal indicative of the variation of the temperature level, a velocity value indicative of a maximum increase in change of temperature level during the time period between the first point in time and the second point in time; comparing the velocity value with a predetermined threshold; and determining that the EGR valve is operational when the velocity value is higher than the predetermined threshold.