US Patent 8474448 Metered dose inhaler

The present invention provides an improved metered dose inhaler utilizing the property of the aerosol canister. The metered dose inhaler includes: a housing body (2); an aerosol canister (3) including a canister body (3a), a valve stem (3b), and a spring urging the valve stem, wherein the valve stem (3b) is held at a fixed position inside the housing body (2), and wherein the canister body (3a) is supported inside the housing body (2) to be depressible against a spring force of the spring; a dose counter (10) including display members (12) and (13) rotatably supported inside the housing body (2), and a control lever (14) swingably supported inside the housing body (2) to rotate the display member (13); and a control cap (20) including a junction member rotatably joined to the control lever (14), and a cap portion (20b) which sheaths the canister body (3a) from a bottom side of the canister body (3a), wherein the control cap (20) causes the control lever (14) to swing.