Mechanical Part Decoration With Conformal Masking and Electroforming

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing decoration methods for mechanical parts, such as watch dials, face issues with burrs on decorative elements and material leakage, leading to scrapped parts and inadequate anchoring of decorative elements.

Innovation Solution

A method where a masking layer is directly formed on the mechanical part, with a first bonding layer promoting adhesion and a second bonding layer enhancing anchoring, using electroforming and filling with conductive materials to create precise, firmly anchored decorative elements.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a mask is placed on the surface of the mechanical part to be decorated, then the decorative elements can be made and fixed to the mechanical part in the same step, but the mask may not be in intimate contact with the surface, causing filling material to leak onto the surface

Engineering Contradiction:
Improvedecoration process efficiencyVSAvoidprecision of decorative elements
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The patent replaces the mechanical mask system with a photoresin-based photolithography system. Instead of physically placing and pressing a mask onto the surface, the photoresin is deposited as a liquid or aerosol that conformally coats the surface, then cured to form the mask pattern. This eliminates the contact issues inherent in mechanical masks while maintaining precise definition of decorative elements.

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

Solution Approach 2:

The photoresin mask forms a flexible, conformal thin film that adapts to the surface topology of the mechanical part. This flexible film ensures intimate contact with complex surfaces without requiring rigid mechanical pressure, preventing material leakage while allowing precise patterning of decorative elements.

Inventive Principle:
Principle #30Flexible shells and thin films

2Device complexity

If a mask is used to form decorative elements, then the process is simpler, but burrs are created on the decorative elements that require additional finishing operations

Engineering Contradiction:
Improveprocess complexityVSAvoidease of finishing operations
Core Design Contradiction:
Device complexityVSEase of manufacture

Solution Approach 1:

The patent changes the material parameters of the mask from rigid (mechanical mask) to soft/conformal (photoresin). This parameter change allows the mask to flex and adapt to surface irregularities during the filling process, preventing burr formation on the decorative elements while maintaining process simplicity.

Inventive Principle:
Principle #35Parameter changes

3Manufacturing precision

If decorative elements are made separately and then fixed to the mechanical part, then the elements can be precisely manufactured, but additional fixing steps are required

Engineering Contradiction:
Improveprecision of decorative elementsVSAvoiddecoration process efficiency
Core Design Contradiction:
Manufacturing precisionVSProductivity

Solution Approach 1:

The patent merges the mask formation and decorative element creation into a single integrated process. The photoresin mask is formed, then the cavity is filled with decorative material directly through the mask opening, combining what would otherwise be separate operations into one efficient workflow that maintains precision while improving productivity.

Inventive Principle:
Principle #5Merging (Combining)

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 method ensures intimate contact between the masking layer and the part, preventing material leakage, achieving precise decorative elements with improved adhesion and anchoring, simplifying finishing operations and reducing scrap rates.

Implementation Method 1

a photoresin mask is formed by photolithography

Methodology Applied
Scientific EffectPhotopolymerisation: Photopolymerisation

Implementation Method 2

filling the volume delimited by the masking layer and the surface to be decorated of the mechanical part by means of a filling material in which it is desired to produce the decorative elements

Methodology Applied
Scientific EffectElectrodeposition: Electrodeposition

Data Source

PatentEP3839659B1Method for decorating a mechanical part
Publication Date: 2024.04.03 RUBATTEL & WEYERMANN
  • EP3839659B1 patent drawingFigure 1~4
  • EP3839659B1 patent drawingFigure 5~7
  • EP3839659B1 patent drawingFigure 8~11

AI summary

The invention relates to a method for decorating at least one surface to be decorated (4) of a mechanical part comprising the following steps: - to obtain the mechanical part to be decorated on which at least one decorative element (2a, 2b) is to be made according to a determined thickness and contour; - to deposit on the surface to be decorated (4) of the mechanical part a masking layer (6) having a thickness at least equal to the thickness of the decorative element (2a, 2b) to be made; - to provide in the masking layer (6) at least one opening (14a, 14b) which coincides with the location on the surface to be decorated (4) of the mechanical part where the decorative element (2a, 2b) is to be made, the cavity (14a, 14b) having a contour which corresponds to the contour of the decorative element (2a, 2b) to be made and defining a volume with the surface to be decorated of the mechanical part;- deposit a bonding layer (28) made of an electrically conductive material over the masking layer (6) and on the surface to be decorated (4), in the places where the cavities (14a, 14b) are provided, to promote the adhesion of the decorative elements (2a, 2b); - fill the volume delimited by the masking layer (6) and the surface to be decorated (4) of the mechanical part with a filler material in which the decorative elements (2a, 2b) are to be made, and - remove the masking layer (6).