Micromechanical Assembly with Oriented Diamond Layers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Recent mechanical watch movements with diamond-coated silicon escapements that are not lubricated suffer from lower regulating power and irreversible degradation of tribological performance, making them unsuitable for industrial manufacturing with acceptable cost and requiring laborious polishing for effective operation.
Innovation Solution
A functional micromechanical assembly with microcrystalline diamond layers having different crystal plane orientations, such as {100} and {111}, at the contact surfaces, reducing frictional energy losses and wear resistance, eliminating interlocking phenomena, and allowing operation without lubrication.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If diamond-coated silicon escapements are used without lubrication, then wear resistance is improved, but regulating power deteriorates and tribological performance degrades irreversibly
Solution Approach 1:
The invention changes the crystallographic orientation parameter of the diamond coating from conventional orientations to specifically oriented crystal planes (such as <100> or <111> directions). This parameter change in crystal structure fundamentally alters the tribological properties, enabling the surface to maintain low friction and high wear resistance without lubrication, thereby resolving the contradiction between wear resistance and regulating power.
Solution Approach 2:
The invention uses diamond coating as a composite material layer on silicon substrate, where the diamond layer provides exceptional hardness and wear resistance, while the controlled crystal orientation ensures optimal friction characteristics. This composite structure combines the advantages of different materials to achieve both high wear resistance and reliable regulating power without lubrication.
2Reliability
If diamond layers are pre-polished before mounting, then tribological performance is improved, but manufacturing complexity and cost increase
Solution Approach 1:
The invention performs the crystal orientation control during the diamond deposition process itself, rather than requiring subsequent polishing operations. By establishing the correct crystallographic orientation <100> or <111> during CVD growth, the optimal tribological performance is achieved directly from manufacturing, eliminating the need for laborious post-polishing steps and reducing manufacturing complexity.
Solution Approach 2:
The invention replaces the mechanical polishing process with a controlled chemical vapor deposition process that directly produces diamond layers with the desired crystal orientation. This substitution of mechanical post-processing with controlled material deposition during manufacturing simplifies the production process while maintaining superior tribological performance.
3Strength
If nanocrystalline diamond layers are used, then wear resistance is improved, but frictional energy losses increase due to interlocking phenomena
Solution Approach 1:
The invention changes the microstructure parameter of the diamond layer by controlling grain size and crystal orientation during deposition. By achieving specific crystal plane orientations (<100> or <111>) and appropriate grain structures, the surface morphology is optimized to minimize interlocking phenomena between contacting surfaces, thereby reducing frictional energy losses while maintaining high wear resistance.
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 assembly achieves tribological performance comparable to or better than state-of-the-art lubricated systems, with reduced wear and frictional energy losses, and eliminates the need for post-processing like polishing, ensuring stable operation of watch components like pallets and escape wheels.
Implementation Method 1
the energy losses due to friction between two contact surfaces of the layers are greatly reduced
Implementation Method 2
The first and second layers of said micromechanical part(s) arranged in such a configuration have greater wear resistance
Data Source
Figure 1~2
Figure 3~4
AI summary
The invention concerns a micromechanical functional assembly (100) comprising at least a first part (10), having a first layer defining a first contact surface intended to come into frictional contact with a second contact surface defined by a second layer, said second layer belonging either to said first part (10) or to at least a second micromechanical part (20) constituting, with said first part(10), said assembly (100), characterised in that the first and second layers each comprise carbon in an amount of at least 50% carbon atoms and in that the orientations of the surface crystal planes of their first and second contact surfaces differ from one another.