A dry powder inhaler includes a housing, a dosing cartridge, and a spacer. Within the housing are a source of pressurized gas, a pressure gauge, a metered valve controlled by a trigger, a safety valve, and an electrostatic charger also controlled by the trigger. The dosing cartridge contains individual...http://www.google.es/patents/US5875776?utm_source=gb-gplus-sharePatente US5875776 - Dry powder inhaler
