Toroidal Return Button Mechanism With Variable Preload

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Solution Overview

Problem

Existing manual control devices are complex, costly, and inefficient, with high manufacturing complexity and costs, lacking modularity and ease of adjustment.

Innovation Solution

A manual control device with a return mechanism comprising a toric element made of elastic material, using receiving elements to impose inflections and variable prestress, allowing simple assembly and efficient operation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a mechanical spring is used as the return mechanism, then the control button can return to its inactive position, but the design and manufacturing complexity increases significantly

Engineering Contradiction:
Improvereturn mechanism functionalityVSAvoiddesign and manufacturing complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent extracts the return mechanism function from complex mechanical spring assemblies and implements it through a simplified toric element integrated into the base structure. The toric element's natural elasticity provides the return force without requiring separate spring components, mounting brackets, or complex adjustment mechanisms.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The toric element serves its own function as both the return mechanism and the structural support element. Its elastic deformation and recovery provide the return force automatically based on its material properties and geometric configuration, eliminating the need for external adjustment or complex mechanical linkages.

Inventive Principle:
Principle #25Self-service

2Reliability

If traditional mechanical spring return mechanisms are used, then the control button returns to inactive position, but the manufacturing cost becomes very high

Engineering Contradiction:
Improvereturn mechanism functionalityVSAvoidmanufacturing cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent merges the return mechanism function with the base structure itself. The toric element is integrated into the base's geometry, combining structural support and return force generation into a single manufactured component. This reduces part count, assembly steps, and overall manufacturing cost while maintaining reliable return functionality.

Inventive Principle:
Principle #5Merging (Combining)

3Reliability

If mechanical springs are used for the return mechanism, then the control button can be returned to inactive position, but the device lacks modularity and ease of adjustment

Engineering Contradiction:
Improvereturn mechanism functionalityVSAvoidmodularity and ease of adjustment
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent enables adjustment of the return mechanism characteristics by changing the toric element's geometric parameters (such as curvature radius, thickness, or inflection point location) or material properties. These parameter changes allow customization of the return force and control button behavior without requiring different mechanical spring assemblies or complex adjustment mechanisms.

Inventive Principle:
Principle #35Parameter changes

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

The device is robust, economical, and easily adjustable, with a return mechanism that ensures stable inactive positions through elastic inflections, providing efficient and durable operation.

Implementation Method 1

the return mechanism comprises a toric element formed from an elastic material, the manual control device comprises receiving elements belonging to the control button and/or the base, the receiving elements making it possible to receive the toric element and to ensure its retention relative to the control button and the base, the receiving elements being arranged so as to locally impose on the toric element at least one inflection generating a variable prestress along the circumference of the toric element

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP4388569B1Manual control device with a toroidal element for returning the control button
Publication Date: 2025.08.06 SOMFY ACTIVITES SA
  • EP4388569B1 patent drawingFigure 1~2
  • EP4388569B1 patent drawingFigure 3~4
  • EP4388569B1 patent drawingFigure 5~6

AI summary

The invention relates to a manual control device (10) which includes a base (11) and a control button (12) defining at least one bearing zone (13a, 13b) allowing manual application of a bearing force to move the bearing zone from a stable inoperative position to an unstable operative position. A return mechanism with a toroidal element (18) made of an elastic material biases the control button (12) in a manner that tends to return the bearing zone (13a, 13b) to the stable inoperative position. Receiving elements (19) make it possible to receive the toroidal element (18) and to hold it in place with respect to the control button (12) and the base (11). The receiving elements (19) are arranged to locally impose at least one inflection (20, 20A, 20B) generating a variable preload along the circumference of the toroidal element (18) on the toroidal element (18).