1. Field of the Invention
The present invention relates to a nebulizer for a fluid having a preferably insertable container containing the fluid, which is closed off, in particular sealed, in the delivered state.
2. Description of Related Art
The starting point for the present invention is a nebulizer in the form of an inhaler sold under the trademark RESPIMAT®, which is illustrated in its basic structure in International Patent Application Publication WO 91/14468 A1 (corresponding U.S. Pat. Nos. 5,497,944 and 5,662,271) and in a specific embodiment in FIGS. 6a, 6b of International Patent Application Publication WO 97/12687 A1 (corresponding U.S. Pat. Nos. 6,726,124 and 6,918,547) and in FIGS. 1 and 2 of the accompanying drawings of this application. The nebulizer has, as a reservoir for fluid which is to be atomized, an insertable rigid container with an inner bag containing the fluid and a pressure generator with a drive spring for delivering and atomizing the fluid.
To supplement the disclosure of the present application reference is made to the complete disclosure of both WO 91/14468 A1 and WO 97/12687 A1 and their U.S. patent counterparts indicated above. Generally, the disclosure contained therein preferably relates to a nebulizer with a spring pressure of 5 to 200 Pa, preferably 10 to 100 MPa on the fluid, with a volume of fluid delivered per stroke of 10 to 50 μl, preferably 10 to 20 μl, most preferably about 15 μl. The fluid is converted into an aerosol, the droplets of which have an aerodynamic diameter of up to 20 μm, preferably 3 to 10 μm. Furthermore, the disclosure contained therein preferably relates to a nebulizer of cylindrical shape of about 9 cm to about 15 cm and about 2 cm to about 5 cm wide and with a jet spray angle of 20° to 160°, preferably 80° to 100°. These values also apply to the nebulizer according to the teaching of the present invention as particularly preferred values.
Before being used for the first time, the nebulizer is opened by undoing a lower housing part and the sealed container is inserted in the nebulizer. The container is opened by a delivery tube which is inserted into the inner bag as the container is put in. Then, the lower housing part is pushed on again.
By rotating the lower housing part of the nebulizer, the drive spring can be put under tension and fluid can be sucked into a compression chamber of the pressure generator. As it is tensioned, the container is moved into the lower housing part in a single movement within the nebulizer, and when tensioned for the first time, it is pierced through its base by a piercing element in the lower housing part to allow air in or out. After manual operation of a locking element, the fluid in the pressure chamber is put under pressure by the drive spring and is delivered through a nozzle into a mouthpiece as an aerosol, without the use of propellant gas.
After opening the nebulizer, the empty container can be replaced by a full one and the nebulizer can then be used again.