| 摘要 |
A balance mechanism incorporates the housing (2) of an aerosol delivery device which accepts and supports a cylindrical medicament cartridge (3). An unstable balance mechanism produces a definitive toggling action between mechanical states at the specified depletion level at which reliable dosage metering is no longer assured. In one embodiment, a fulcrum structure (1) is formed in one side of an inhaler housing (2) that causes the housing and the cartridge (3) to pivot or rotate about an axis to indicate the depletion of the useful mass of the contents of the cartridge. In this embodiment, the rotation of the housing (2) and cylindrical container (3) is about the pivot axis located at the apex of the fulcrum (1) formed in the housing when the housing is supported on a hoizontal surface. The mechanism can also utilize the known mass of an associated mouthpiece cover (4) or other bias weight to modify the balance criterion so as to assess whether the vessel contains a minimum reserve quantity of medicament above and beyond the reliable dosage metering level. A stable balance mechanism may additionally or alternatively be incorporated in the housing of the inhaler for assessing the continuous state of depletion of the aerosol vessel ranging from completely full to completely empty. The stable balance mechanism incorporates a pivoting needle (47) that indicates an analog estimate of the depeletion level. |
