Appliance and method for removing noise from a motor characteristic signal in a laundry treating appliance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Laundry treating appliances face challenges in accurately identifying and addressing imbalances during the spin phase due to noise in motor characteristic signals, which traditional time-based filtering methods fail to effectively filter, leading to inaccurate imbalance determination and potential vibrations.
Innovation Solution
The method involves spatial sampling of motor characteristic signals on a per revolution basis, followed by filtering to remove noise, allowing for precise evaluation of imbalances and improved signal accuracy independent of drum speed variations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional time-based filtering methods are used to process motor characteristic signals, then the processing is simple and fast, but the noise removal is ineffective leading to inaccurate imbalance detection
Solution Approach 1:
The patent transforms the signal processing approach from the time domain to the spatial domain by sampling motor characteristic signals at different angular positions around the drum rotation. This dimensional change allows noise removal filters to effectively distinguish between actual imbalance signals and noise, significantly improving imbalance detection accuracy while maintaining manageable system complexity
Solution Approach 2:
The patent changes the sampling parameter from time-based to position-based (angular position around the drum). By sampling signals at specific angular positions rather than continuous time intervals, the system creates a spatial representation of motor characteristics that enables more effective noise filtering and accurate imbalance detection
2Measurement precision
If spatial sampling on per revolution basis is implemented, then noise filtering effectiveness is improved, but the processing complexity increases
Solution Approach 1:
The patent divides the motor characteristic signal into discrete segments corresponding to specific angular positions around the drum rotation. By segmenting the signal spatially rather than processing it as a continuous time signal, the system achieves effective noise filtering through comparison across revolutions while keeping processing complexity manageable through structured data organization
Solution Approach 2:
The patent implements periodic spatial sampling at predetermined angular positions during each drum revolution. This periodic sampling approach creates consistent data patterns that facilitate noise removal through comparison across multiple revolutions, improving signal accuracy while maintaining efficient processing through regular intervals
3Reliability
If noise is not effectively filtered from motor characteristic signals, then the processing remains simple, but imbalance determination becomes inaccurate causing vibrations
Solution Approach 1:
The patent introduces a noise removal filter that operates in the spatial domain as an intermediary processing step between signal acquisition and imbalance determination. This intermediary filter effectively removes noise while preserving actual imbalance signals, significantly improving operation reliability and preventing vibrations without requiring overly complex filtering systems
Data Source
AI summary
An apparatus and method of sensing a motor characteristic signal in a laundry treating appliance having a drum rotated by a motor about a rotational axis, sampling the motor characteristic signal, filtering the motor characteristic signal, and evaluating the filtered motor characteristic signal for the presence of a predetermined condition corresponding to the motor characteristic signal.