Cylindrical gears are the most common type of manufactured gear. They are typically usedfor low and medium speeds because at high speeds, if they are not rectified, or corrected,they produce a variable noise.
These gears are called internal gears because the cut takes place on the inside part of a ringor a wheel. Their main characteristic is that the gaps between their teeth correspond tothose on an external cut. They are used mainly in planetary groups.
This type of gear allows the transmission of movement between axes that are separated.The mechanism consists of a closed chain whose links lubricate the fixed sprockets to theaxes of the conducting and conducted mechanisms.