Dishwasher Additive Sensor Timing to Reduce Movement Interference

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Users face difficulties in accurately determining the level or volume of wash additives in dishwasher reservoirs, as previous attempts with sensors have been unsatisfactory due to issues like residue and inaccurate readings caused by opening and closing the door.

Innovation Solution

A method and apparatus for a dishwasher that includes a door with an additive sensor to measure the wash additive volume after maintaining the door in an open position for a preset period, ensuring accurate detection by minimizing interference from additive movement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Difficulty of detecting and measuring

If a sensor is installed to automatically detect the amount of wash additive, then measurement capability is improved, but measurement precision deteriorates due to door opening-closing causing additive movement and residue

Engineering Contradiction:

Improveadditive volume detectionVSAvoidadditive volume measurement accuracy

Core Design Contradiction:

Difficulty of detecting and measuringVSMeasurement precision

Solution Approach 1:

The system performs preliminary actions by detecting door open/closed state and waiting for a predetermined period before initiating the additive volume measurement. This ensures the additive has settled and the door is stable, eliminating movement artifacts and residue interference that would otherwise degrade measurement precision.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system continuously monitors door state and uses this feedback to determine the appropriate timing for measurement. By detecting when the door transitions to a closed state and maintaining that state for the required duration, the system ensures measurement conditions are optimal before the sensor takes readings.

Inventive Principle:

Principle #23Feedback

2Ease of operation

If the door is opened frequently for loading/unloading, then ease of operation is improved, but measurement precision deteriorates due to additive movement within the reservoir

Engineering Contradiction:

Improvedoor accessibilityVSAvoidadditive volume measurement accuracy

Core Design Contradiction:

Ease of operationVSMeasurement precision

Solution Approach 1:

The system waits for a predetermined period after the door closes before performing measurement. This preliminary waiting period allows any additive movement caused by door opening to complete and settle, ensuring the additive is in a stable state for accurate measurement without restricting user access frequency.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system performs measurements periodically based on door state transitions rather than continuously. By triggering measurements only after the door has been closed for a predetermined period, the system achieves accurate readings while allowing frequent door operations for loading and unloading.

Inventive Principle:

Principle #19Periodic action

Data Source

PatentUS11344176B2Dishwasher appliances and methods for determining wash additive levels

Publication Date: 2022.05.31 HAIER US APPLIANCE SOLUTIONS INC

AI summary

A method of operating a dishwasher appliance, as provided herein, may include detecting a door of the dishwasher appliance in an open position and determining the door is maintained in the open position for a preset minimum continuous period. The method may further include detecting the door in a closed position following the preset minimum continuous period. The method may still further include measuring an additive volume of a wash additive in an additive compartment on the door while the door is in the closed position following the preset minimum continuous period.