Leonardo dedicated great attention to the design of revolving thrust bearings: mechanisms to reduce or eliminate the effect of wear and tear from friction from moving parts in machines.
This model consists of a circular platform upon which eight spheres are arranged in a ring, interspersed with the same number of concave rolling spools fitting together with them perfectly. The balls are free to turn without bumping into one another, and are held together by the rollers that prevent them from leaving their seating.
These incredibly modern thrust bearings, generally called “ball bearings,” are nowadays widely used in all machines with moving parts.
Technical informations
Type of exhibit
Model
Collection
Material
Carved wood
Measures
Height: 17 cm; Diameter: 6.5 cm.
Storage location
Relationship with the original work
Source: Leonardo da Vinci, Madrid Codex I, f. 20 v
Location
Museo Leonardiano, Counts Guidi's castle, ground floor
Digital archive
Related exhibits
Last update: 11 November 2025, 12:48