The aim of this paper is to present a design activity conducted for developing a new device for automatic breathing applications for developing countries using, to generate the necessary airflow, an Ambu (Auxiliary Manual Breathing Unit), a self-expanding bag for manual ventilation, used for support respiratory activity. The idea is to create a mechanism to automate the device, through the use of open-source components and/or in any case easily available, and make it usable for intensive care applications for sedated patients or to support ventilatory activity in patients in cardiac arrest. The requirements of the device are essentially two: high reliability guaranteed by the automatic and/or mechanical transmission and adjustment mechanism of the airflow and the characteristic breathing times, all made accessible at a low cost.