Pneumatic machine tool

A pneumatic machine tool comprising:

• a handle with one end being a first pivot connecting end, the handle comprising a main flow channel extending to the first pivot connecting end, and a switch assembly provided in the main flow channel, wherein the switch assembly determines whether the main flow channel is in a ventilation state or a stopped ventilation state;
• and
• a tool head, comprising a main body, a tool driving assembly disposed in the main body, and two pivot connecting arms formed on the main body and disposed side by side, wherein the two pivot connecting arms served as a second pivot connecting end of the tool head to be assembled with the first pivot connecting end through a pivot shaft, wherein the main body is formed with a chamber provided for disposal of the tool driving assembly, and at least one secondary flow channel communicating with the chamber and extending to the two pivot connecting arms;
• wherein the pivot shaft comprises a transfer flow channel and two transfer ports communicating with the transfer flow channel, and the main flow channel and the at least one secondary flow channel form a ventilation path through the two transfer ports.