Seal for an inhalation device

Abstract

The invention relates to the field of inhalation devices for liquids. In particular, the invention relates to an improved seal construction for an inhalation device having a nebulizing nozzle and a piston which moves relative to a pumping chamber in order to generate pumping pressure and to an inhalation device comprising such seal.An inhalation device for medically active liquids (F) for generation of an aerosol comprises a housing (), an impingement-type nozzle () for generating the nebulised aerosol by collision of at least two liquid jets, the nozzle () being firmly affixed to the user-facing side of the housing () such as to be immobile relative to the housing (), inside the housing () the inhalation device comprises a reservoir () for storing a liquid (F),a pumping device with a pumping chamber () for generation of a pressure inside said pumping chamber (), wherein the pumping chamber () is fluidically connected with the reservoir (), a riser pipe () which can be received with at least one reservoir-facing, interior end (A) in said pumping chamber (), and said nozzle () which is connected liquid-tight to an exterior end (B) of the riser pipe (), wherein the interiorvolume of the pumping chamber () is changeable by means of relative motion of the pumping chamber to the riser pipe () or vice versa. A gap () can be present between an outside of said riser pipe () and an inside of said pumping chamber (), and a seal () bridging said gap () in order to minimize pressure loss when a pressure is generated inside said pumping chamber ().Said seal () can be fixed to said outside of said riser pipe (), and be moveable with respect to said inside of said pumping chamber ().