A STAND-ALONE COUNTER FOR A METERED DOSE INHALER

摘要

A dose counter for a metered dose inhaler comprises a button 41 attached to the closed end of a medicament-containing aerosol canister 30 by means of a resilient skirt 42. The button 41 has means for sensing applied pressure and, on its top surface is provided with a count display 43 which indicates the number of doses of medicament which have been delivered. Body portion 41 of the button houses a processing chip which determines whether a predetermined force has been applied to the pressure sensing means. When this force threshold is reached, the chip sends an electrical impulse to the count display 43 to increment it.