TH3988B - Devices in a powder dosing device by inhalation - Google Patents

Abstract

An inhalation powder dispenser, as previously described, is intended for the inhalation of an air stream containing a pharmacologically active compound in a micronized form. The inhalation powder dispenser consists of an injector unit (2) with an inlet (2a) and a container unit (3) containing a dose-dispensing unit (6) for dispensing the active compound. At least some of the air stream generated by the inhalation is drawn through an air tube (7) in the container unit (3), which extends from the ambient air inlet (8) through the aforementioned dose-dispensing unit (6) to the injector unit (2). In this invention, such a diffraction device, in the form of a helical port (13), etc., is arranged to generate a forceful diffraction for the purpose of dispersing the inhaled powder particles to a particle size distribution of less than 5 µm.

Claims (10)

1. In an inhalation drug delivery device, the air stream generated during inhalation contains a container for the pharmacologically active compound, which has been atomized or micron-sized. A tube passes through the container and has an air inlet, a path for delivering the compound to the tube, an outlet for the outflow of the compound from the incoming air stream through the air inlet (at least partially), and a nozzle with a single nozzle hole connected to the outlet of the tube. The tube and nozzle together form a channel for releasing the compound upon inhalation. Improvements include a deflection path within the channel to forcefully diffract and accelerate the air and compound streams through the channel relative to the channel axis. The deflection path is fixed within the channel along at least one section of the channel between the particle delivery path and the nozzle hole. The deflection path must have a radial boundary toward the channel axis large enough that any radial boundary along the channel axis adjacent to the deflection path is small relative to the radial boundary of the deflection path. Therefore, the diffraction pathway serves to promote the dispersion of the drug powder into particles within the inhalable range by causing collisions between these particles and the diffraction pathway, or between them themselves. 2. Improvements to Claim 1, in which the diffraction trajectory comprises diffraction components that are shaped and positioned to deflect the airflow and compounds in a rotational manner relative to the channel axis. 3. Improvements under claim number 2, which includes axial clearance in the channel adjacent to the deflector trajectory to reduce airflow resistance and compounds. 4. An improvement under claim 3, whereby the ratio of the radial boundary of the open space to the radial boundary of the diffraction trajectory shall not be greater than two. 5. Improvements under claim 2, in which the bending trajectory is shaped to form at least one helical segment along the said section of the channel. 6. Improvements under claim number 5, which are located in the injector nozzle adjacent to the injector hole. 7. Improvements under claim 6, in which a portion of the nozzle that is directly over the stream, relative to the direction of airflow and compounds passing through this channel, has a progressively decreasing cross-sectional area to increase the velocity of the airflow and compounds. 8. Improvements under claim number 5, which is located in the direct passage between the dose release pathway and the outlet of the tubing. 9. Improvements pursuant to claim number 5, whereby the cross-sectional area of the helical section is between 5 sq mm and 50 sq mm and the length of such section is between 5 mm and 50 mm. 10. Improvements under claim 4, which include at least one air inlet leading to a channel between the dose release path and the nozzle to atomize diluted air into the air stream and compound.