摘要 |
An inhaler for medical aerosols includes a flow sensor (32) in the form of a piston which is movable against a spring bias (35) in response to inhalation. Movement of the piston unseats a valve member (30) thus triggering the release of a pressurised dose through a nozzle (67). A uniform impedance to the flow of air is provided throughout the movement of the piston to avoid any discontinuity in the flow. The apparatus is particularly suited for inhalers used in the treatment of asthma. <IMAGE> |