Printing press
Between 1400 and 1550 there is an extraordinary development of printing with movable types invented by J.
Gutenberge in Magonza in 1450: Venice, Rome, Florence and Milan become the first and most prestigious European
centers. Leonardo immediately notices this revolutionary technique for the opportunity of planning innovations
it offers along with the rising textile technology.
The printing press he projects, presents an attempt at automatizing the working phases: The press is worked by the lever on the right which, when turned, pushes down on the press by means of a large screw.
At the same time, the large cogwheel at the top turns a pulley, which pulls the plate holding the paper under the press. In a single movement, the press loads the sheet of paper and prints the page
Crane of Filippo Brunelleschi
The young apprentice Leonardo is assiduously present at the building site where they are completing the dome of Santa Maria del Fiore in Florence. projected by F. Brunelleschi (32 metres high, and with a diameter of 55 metres). In his notebooks he puts down several “photos” of the building machines at the site; among these there are some cranes and he, as usual, projects remarkable improvements.
The model represents a crane that rotates at the base, with a hoist for the lifting of the weight and an upper slide driven by a screw to move, horizontally, the materials on the work surface. A complement of an electric engine would make this crane really similar to the ones used today.
Chain drive
In two papers of the Codices, Leonardo studies for the first time the motion transmission by means of a chain: these
projects, with their graphic precision, belong to his personal research to find mechanisms for the transformation and transmission of motion between mechanic parts. The systems used at the time were limited to the use of cams, to gears with wooden stakes, to ropes and belts. The construction of a chain with iron links and respective crown wheels required machines that had not been invented yet.
Only at the end of the XVIII century the chain transmission will be used to a bicycle, the modern bicycle.
Winch hammer
Among Leonardo’s projects there is this original attempt to make a hammer winch work. Turned by two cranks, the cylinder on the left raises and drops three triphammers one after the other.
The slanting surface of the wedge under each hammer bears down on the pegs of the larger cylinder, making it turn. The central wheel works also as ratchet in order to preclude the inversion of motion (Leonardo called it servant).
The effectiveness of such a device is dubious, but it enables us to better appreciate the Maestro’s “mind”: the solution of a problem does not necessarily imply a single solution.
