This ventilator is designed with two bellows, one to deliver oxygen and the other to remove carbon dioxide from a patient. When one bellow is removing carbon dioxide from a patient the other bellow is filling with oxygen. When the first bellow is expelling the carbon dioxide the other bellow is sending oxygen to the patient.
It is designed to operate continuously with an adjustable number of cycles and an adjustable amount of air exchanged with each cycle.
This ventilator is designed to be built by a person who has a woodworking shop and has access to a welder. Most materials may be found on hand, can be obtained from hardware or lumber yards, and other local stores.