Domestic appliance with improved rotary selector switch and method for operating the domestic appliance

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Solution Overview

Problem

Household appliances with rotary selectors lack flexibility in arranging and increasing the number of control and display elements, making the display of information on the control panel less user-friendly.

Innovation Solution

A household appliance with a rotary selector featuring touch-sensitive surfaces that change electrical capacitance upon user interaction, allowing for flexible arrangement and increased display elements, where the touch-sensitive surfaces on the cover and base interact to provide position feedback, enabling intuitive program selection and visual information display through a projection device.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If traditional rotary selectors are used with fixed control and display elements, then the structure is simple and reliable, but the flexibility in arranging and increasing the number of control and display elements is limited

Engineering Contradiction:
Improveflexibility in arranging control and display elementsVSAvoidstructure complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent replaces traditional mechanical control elements (buttons, switches) with a touch-sensitive surface that detects electrical capacitance changes. This allows the rotary selector to have flexible arrangement of control and display elements without additional mechanical complexity, as the touch-sensitive surface can detect user interactions across different positions and orientations.

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

Solution Approach 2:

The rotary selector integrates multiple functions into a single component: it serves as both a rotational control mechanism and a touch-sensitive display interface. The cover surface functions as both a protective element and an interactive touch surface, allowing the same structure to provide both mechanical rotation capability and capacitive touch detection for program selection.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Adaptability or versatility

If more control and display elements are added to the rotary selector, then the functionality and user-friendliness improve, but the device complexity and manufacturing difficulty increase

Engineering Contradiction:
Improvenumber of control and display elementsVSAvoidmanufacturing difficulty
Core Design Contradiction:
Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

The patent changes the detection parameter from mechanical contact to electrical capacitance measurement. By detecting changes in electrical capacitance at different positions on the touch-sensitive surface, the system can identify user interactions without requiring separate mechanical sensors for each control element, simplifying manufacturing while enabling multiple interaction points.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The touch-sensitive surface creates an electrical field that extends through the rotary selector structure, allowing multiple detection points to be established without adding proportional hardware complexity. The capacitive sensing principle allows the same basic sensor structure to detect interactions across the entire surface area.

Inventive Principle:
Principle #26Copying

3Ease of operation

If the rotary selector uses touch-sensitive surfaces with electrical capacitance detection, then the user interaction flexibility improves, but the complexity of signal generation and evaluation increases

Engineering Contradiction:
Improveuser interaction flexibilityVSAvoidsignal generation and evaluation complexity
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The touch-sensitive surface utilizes the user's body (finger) as part of the capacitive sensor system. When a user touches the surface, their body capacitance interacts with the electrical field, automatically generating a detectable signal change without requiring additional activation mechanisms or complex input protocols.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The system provides visual feedback through illuminated display elements that respond to touch interactions. The control unit evaluates capacitance changes and activates corresponding display segments to show selected programs or options, creating an intuitive feedback loop that guides user interaction without requiring complex communication protocols.

Inventive Principle:
Principle #23Feedback

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

Enhances user interaction by allowing flexible placement of control and display elements, improving user-friendliness and enabling recognition of malfunctions, with standardized electronics and modular design for easy replacement and customization.

Implementation Method 1

when touched or approached by a user's body, a change in electrical capacitance can occur

Methodology Applied
Scientific EffectElectrical capacitance change: Capacitance

Data Source

PatentEP3474721B1Domestic appliance with improved rotary selector switch and method for operating the domestic appliance
Publication Date: 2020.06.03 BSH HAUSGERATE GMBH
  • EP3474721B1 patent drawingFigure 1~2
  • EP3474721B1 patent drawingFigure 3~4
  • EP3474721B1 patent drawingFigure 5

AI summary

The invention relates to a domestic appliance with a housing, wtih an operating panel 1, which on an outer surface 2 has a rotary selector switch 4 which can be rotated about an axis of rotation 3 and has a cover surface 5, a lateral surface 6 and a base surface 7, and with a control unit 8, wherein the rotary selector switch 4, on at least part of its lateral surface 6, has a first touch-sensitive surface 9 and, on part of the base surface 7, has a second touch-sensitive surface 10, and wherein the second touch-sensitive surface 10 is located opposite an inner touch-sensitive surface 11 on an inner surface 12 of the operating panel 1 such that the second touch-sensitive surface 10 and the inner touch-sensitive surface 11 can interact with one another. The invention also relates to a method for operating said domestic appliance.