Cleaning Device Fluid Tank Empty Detection Using Motor EMF Signals

Solution Overview

Problem

Conventional cleaning devices, such as wet and dry vacuums, fail to notify users when the fluid container becomes empty, leading to degraded user experience due to the inability to supply fluid for cleaning operations.

Innovation Solution

A system utilizing a fluid pump and controller to determine fluid tank emptiness by analyzing electromotive force (EMF) generated by the motor, providing user notifications when the tank is empty, without the need for additional sensors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional cleaning devices are used without additional sensors, then device complexity is reduced and manufacturing cost is lower, but the ability to detect fluid tank emptiness is lost and user experience deteriorates

Engineering Contradiction:

Improvefluid tank empty detectionVSAvoiddevice complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The motor serves dual functions: pumping fluid and generating EMF signals for tank level detection. The system uses its own operational characteristics (EMF generation during pumping) to detect fluid availability, eliminating the need for external sensors or additional detection mechanisms.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent replaces mechanical or optical sensor-based detection systems with an electrical field-based detection method. By measuring the EMF generated by the motor during operation, the system detects fluid tank status without physical contact or additional mechanical components.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Measurement precision

If additional sensors are added to detect fluid tank emptiness, then detection reliability is improved, but device complexity and manufacturing cost increase

Engineering Contradiction:

Improvetank emptiness detection accuracyVSAvoiddevice complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The motor serves dual functions: pumping fluid and generating EMF signals for tank level detection. The system uses its own operational characteristics (EMF generation during pumping) to detect fluid availability, eliminating the need for external sensors or additional detection mechanisms.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent replaces mechanical or optical sensor-based detection systems with an electrical field-based detection method. By measuring the EMF generated by the motor during operation, the system detects fluid tank status without physical contact or additional mechanical components.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Ease of operation

If the fluid container is made opaque or disposed within another component, then device aesthetics and integration are improved, but user ability to visually check fill level is lost

Engineering Contradiction:

Improveuser notification capabilityVSAvoidvisual fill level information

Core Design Contradiction:

Ease of operationVSLoss of information

Solution Approach 1:

The system provides active feedback to the user about fluid tank status. The controller monitors EMF signals and generates notifications (visual, audible, or haptic) to inform users when the tank is empty, replacing passive visual inspection with active electronic feedback mechanisms.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The patent replaces mechanical or optical sensor-based detection systems with an electrical field-based detection method. By measuring the EMF generated by the motor during operation, the system detects fluid tank status without physical contact or additional mechanical components.

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

Ensures fluid availability by alerting users when the tank is empty, enhancing user experience and maintaining device functionality without adding costly sensors.

Implementation Method 1

The fluid pump includes a motor configured to drive the pumping of the fluid of and to generate an electromotive force (EMF)

Methodology Applied

Scientific EffectElectromotive force (EMF) generation: Electromagnetic Induction

Data Source

PatentUS20260007288A1Cleaning device with fluid tank empty detection

Publication Date: 2026.01.08 SHARKNINJA OPERATING LLC

AI summary

Various cleaning devices with fluid tank empty detection and methods related thereto are provided. In general, a cleaning device can be configured to determine whether a fluid container is empty using an electromotive force (EMF) at a fluid pump configured to pump fluid from the fluid container. When the fluid container becomes empty, fluid cannot be supplied from the cleaning device to a surface until more fluid is added to the fluid container. Thus, by determining whether the fluid container is empty, a user of the cleaning device may be made aware when the fluid container becomes empty and needs refilling (or replacement).