Flush Valve Code Disc Sensing for Calibration-Free Plate Position

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional flush valve position detection in vacuum toilets is inaccurate, requires calibration, and is not robust enough for harsh environments, leading to operational issues and potential damage.

Innovation Solution

A flush valve with a rotating component featuring gradated markings and a code reader for precise position detection, eliminating the need for calibration and enhancing reliability in harsh conditions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If potentiometers are used to detect plate position, then position detection capability is provided, but manufacturing complexity increases due to required calibration and tuning

Engineering Contradiction:
Improveplate position detection accuracyVSAvoidassembly calibration complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces the mechanical potentiometer-based position detection system with an optical code reading system. A code disc with radially extending transmissive and opaque segments is positioned on the motor shaft, and a code reader detects the code pattern to determine plate position. This substitution eliminates the need for mechanical calibration and tuning while providing accurate position detection throughout the plate's range of motion.

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

2Ease of manufacture

If conventional switches are used for position monitoring, then basic open/closed position detection is achieved, but measurement precision is insufficient for intermediate positions

Engineering Contradiction:
Improvesimplicity of position monitoringVSAvoidintermediate position detection accuracy
Core Design Contradiction:
Ease of manufactureVSMeasurement precision

Solution Approach 1:

The code disc is segmented into multiple radially extending transmissive and opaque segments arranged in a specific code pattern. This segmentation allows the code reader to detect not only the open and closed positions but also multiple intermediate positions of the plate, providing continuous position information throughout the range of motion without requiring complex mechanical switches for each position.

Inventive Principle:
Principle #1Segmentation

3Reliability

If accurate position detection is implemented, then operational reliability improves, but device complexity and cost increase

Engineering Contradiction:
Improvevalve operation reliabilityVSAvoidposition detection system complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent uses a code disc that creates an optical code pattern representing the plate position. The code reader optically reads this pattern to determine position, replacing complex mechanical position sensing mechanisms with a simple optical copying and recognition system. This approach provides reliable position detection while keeping the system simple and cost-effective.

Inventive Principle:
Principle #26Copying

4Measurement precision

If potentiometers are used for position detection, then position feedback is provided, but the system becomes sensitive to environmental contaminants and vibration

Engineering Contradiction:
Improveposition feedback accuracyVSAvoidsensitivity to contaminants and vibration
Core Design Contradiction:
Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The patent replaces the mechanical potentiometer system with an optical code reading system. The code disc with its pattern of transmissive and opaque segments and the optical code reader create a non-contact measurement system that is immune to mechanical wear, electrical interference from contaminants, and vibration, while maintaining accurate position feedback throughout the harsh vacuum toilet environment.

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

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 solution provides accurate, reliable, and calibration-free position detection of the flush valve plate, ensuring proper operation and durability in vacuum toilet environments.

Implementation Method 1

a code reader, fixed relative to the valve housing, and positioned to read the code as it passes the code reader on rotation of the valve plate

Methodology Applied
Scientific EffectOptical detection: Light

Data Source

PatentEP4484661A1Flush valve position detection
Publication Date: 2025.01.01 BE AEROSPACE INC
  • EP4484661A1 patent drawingFigure 1~2
  • EP4484661A1 patent drawingFigure 3A~3C
  • EP4484661A1 patent drawingFigure 4A~4D

AI summary

A flush valve comprising: a valve housing (10) defining a port (20); and a valve plate (30) arranged to rotate in a plane, relative to the port, such as to vary a degree of coverage of the port by the valve plate depending on the rotational position of the plate; the flush valve further comprising: a component (62) that rotates with the valve plate; a code (70, 70', 70") formed of gradated markings provided on the component, the gradated markings formed such that a characteristic of the code varies across the component in the rotation direction; and a code reader (75), fixed relative to the valve housing, and positioned to read the code as it passes the code reader on rotation of the valve plate.