EP0839544A2 — Inhalers

USPTO Abstract

The invention relates to inhaler products, such as medicaments, and particularly to an inhaler for transferring to a patient a metered dose of medicament contained in a pressurised dispensing container. The inhaler comprises a housing for receiving a pressurised dispensing container of medicament and a mouthpiece for insertion into the mouth of a user of the inhaler. An outlet in the housing communicates with the mouthpiece via a duct ending in an outlet. At least one air inlet is provided for allowing air into the inhaler, the air inlet(s) being positioned downstream relative to the duct outlet. A restricted airflow passage is provided between the air inlet(s) and a location adjacent to the outlet of the duct. The inhaler further comprises vortex generating means in the restricted airflow passage, such that, in use, when a user inhales through the mouthpiece, a swirling airflow is created from the inlet(s) to the mouthpiece along the passage towards the duct outlet, such that the airflow has a component directed in reverse to the airflow from the duct outlet of the mouthpiece.