Swiss lever escapement mechanism

3D Model

The animation shows the working principle of a mechanical watch. It consists of the following elements: balance wheel, hairspring, pallet fork and escape wheel.

The tricky job is to integrate the deformation of the hairspring. I started from a 3D model of the mechanism and extracted each part in STL format. As for the spring, I performed FEA simulations (1st eigenfrequency) and exported the results as VRML files (.wrl). Here, the challenge is to extract the meshes while keeping the same number of vertices on each deformed shape. In Blender, shape keys were used to animate the spring.

• CAD (STEP file): Simplified model of watch movement ETA 6497-1 by Steen Winther

• Softwares: SolidWorks simulation, Blender

You may also enjoy the vintage movie “How a watch works” (Hamilton Watches Co., 1949) that explains the principle of mechanical watches with the help of a giant in line movement.