Machines and Mechanisms Designed by Leonardo

In this image, Leonardo has drawn a serrated wheel (called a ritenáculo) that acts as a safety mechanism in a system for hoisting weights. The locking system consists of a catch that fits into the teeth of the wheel in such a way that, when horizontal, the catch is held in place by its own weight.

This intriguing machine uses consecutive strikes by three wedge-shaped hammers to lift weights. Leonardo studied the length of the constituent parts to ensure that the machine worked continuously and at a steady pace.

This device is for unfolding octagonal covers. Turning the handle makes the shaft turn. This moves the ring, along with the articulated arms and spokes that support the cover.

Here, Leonardo uses a piece of wood (a wedge), shaped into a very sharp dihedral angle, to fit one object to another, making it impossible to separate them. He advises using it for the legs of a stool.  

Leonardo invented several systems that used levers and cogwheels to transmit power and motion. This system enables versatile transmission in watches, machine tools, and vehicles. 

This diagram shows two bevel gears that interlock to transmit power and change the direction of movement by 90 degrees, reducing the speed of the output rotation. It works by turning a handle. It could be applied to vehicles, where movement needs to be transmitted and the speed of rotation reduced.