Membrane PCB Control Interface for Tolerance-Stable Appliance Operation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing control devices for household appliances often require multiple components and struggle to maintain manufacturing tolerances, leading to increased complexity and costs.

Innovation Solution

The operating device features a membrane and circuit board arrangement with a plunger that forms an electrically conductive connection, allowing for a reduced number of components and improved tolerance compliance, enabling standardized and modular design for various operating concepts.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If multiple layered components are used in mechanically designed control devices, then function control is achieved, but maintaining specified tolerances during manufacturing becomes problematic

Engineering Contradiction:
Improvefunction controlVSAvoidtolerance maintenance
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The patent merges the membrane with the circuit board by directly attaching electrical contacts to the circuit board, eliminating the need for separate layered components and reducing tolerance accumulation in the assembly process

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The circuit board serves multiple functions: it acts as both the structural support and the electrical circuit carrier, while also providing mounting positions for electrical contacts, thereby reducing the number of separate components and simplifying the assembly process

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

2Adaptability or versatility

If customized panels, electrical circuits, and mounting devices are used for each operating concept, then specific assembly variants are required, but device complexity and manufacturing costs increase

Engineering Contradiction:
Improveoperating concept customizationVSAvoidassembly variant complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The circuit board is designed as a universal component that can accommodate different operating concepts (buttons, rotary selectors, jog dials) through standardized mounting positions and electrical contact arrangements, eliminating the need for customized panels and mounting devices for each operating concept

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

Solution Approach 2:

The control device is segmented into independent functional elements (operating elements, electrical contacts, circuit board) that can be independently designed and assembled, allowing different operating concepts to be implemented by simply changing the operating elements while keeping the base structure standardized

Inventive Principle:
Principle #1Segmentation

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

This solution reduces the number of necessary components, simplifies the mechanical interface, and optimizes tactile behavior, while also providing cost-effective and versatile design options for household appliances.

Implementation Method 1

The membrane is preferably elastic or flexible, so that the plunger can locally deform the membrane and press it against the circuit board

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

The plunger is preferably arranged in the operating unit, tensioned by a spring, and protrudes from the operating unit facing the diaphragm arrangement

Methodology Applied
Scientific EffectSpring force: Spring

Data Source

PatentEP3736674B1Operating device for operating household appliances
Publication Date: 2025.06.11 BSH HAUSGERATE GMBH
  • EP3736674B1 patent drawingFigure 1~2
  • EP3736674B1 patent drawingFigure 3~4
  • EP3736674B1 patent drawingFigure 5~6

AI summary

The invention relates to an operating device (1) for functionally controlling a domestic appliance (2), and the operating device (1) is provided with at least one operating unit (4) having at least one plunger (8, 9) and at least one membrane arrangement (12) having a membrane (14) which is electrically conductive at least on one side and an electrically conductive printed circuit board (16), wherein the printed circuit board extends parallel to the membrane (14) and is spaced apart from the membrane (14), the membrane (14) can be pressed against the printed circuit board (16) by at least oneplunger (8, 9) of the actuating unit (4) in order to create at least one electrically conductive connection (18, 19), and a measurable resistance or resistance change adjustment function of the electrically conductive connection (18, 19) can be set. The invention also relates to a household appliance (2) and to a method for producing an operating device (1).