Other

Minnesota Mining and Manufacturing Company

Riker Laboratories Inc.

Msp Corporation

Nicholas C Miller

Peter D Hodson

Virgil Alan Marple

Andrew M Bryant

A measuring system and process for measuring the size distribution of particles in an aerosol with a time-varying flow utilizing a measuring instrument that utilizes a time-invariant flow rate is provided. The process includes employing a vacuum source to establish a constant flow through the measuring instrument. The vacuum generated by the vacuum source is used to draw an aerosol stream through an inlet incorporating a second stream of relatively particle free gas. The first and/or the second stream may be adjusted so that at any instant of time, the sum of the two streams is a constant value equal to the flow rate through the measuring instrument.

Apparatus and process for aerosol size measurement at varying gas flow rates

A metered dose dispensing valve is described that is particularly suitable for dispensing metered volumes of a pressurised aerosol formulation. The valve comprises a chamber, and a valve stem extending into the chamber and movable relative to the chamber between non-dispensing and dispensing positions. The valve stem has a configuration and the chamber has an internal configuration such that a metered volume is defined therebetween and such that during movement between its non-dispensing and dispensing positions the valve stem sequentially: (i) allows free flow of aerosol formulation into the chamber, (ii) defines a closed metered volume for pressurised aerosol formulation between the external surface of the valve stem and internal surface of the chamber, and (iii) moves with the closed metered volume within the chamber without decreasing the volume of the closed metered volume until the metered volume communicates with an outlet passage thereby allowing dispensing of the metered volume of pressurised aerosol formulation.

Free flow aerosol valves

The present invention relates to a low particle loss cascade impactor with particle collection in externally removable cups for determining the size distribution of particles delivered form an aerosol atomizer. A plurality of downwardly facing cavities formed in the body are arranged from a first end to a second end of the body in a generally zig-zag pattern. Each cavity has a generally cylindrical inner wall surface defining an opening facing in a second direction and a surface facing in a first direction. An entrance passage extends from the outer surface of the body at the first end to a center region of a first cavity. The impaction stage is positioned such that a center line of the impaction stage intersects a center bisecting plane passing through the body at an included angle between about 10.degree. to 80.degree.. The body has a plurality of cavity passages which extend between adjacent cavities from the inner wall of one cavity adjacent the outlet opening of that cavity to a central region of the adjacent cavity. Nozzles are formed in the entrance passage and in each cavity passage. Part of the collection and impaction surfaces are provided adjacent to each cavity for the collection of particles. An airflow generator connected to the cavity next adjacent the second end of the body causes air to flow into the body at the entrance passage and flow through the plurality of cavities via the cavity passages.

Low particle loss cascade impactor

An apparatus for administering a nebulized substance to a subject comprising a nebulizer and a valve assembly which permits continuous and constant flow of pressured gas through the nebulizer even when the apparatus is not being used to administer the substance to a subject. This steady state operation of the nebulizer provides for administration of a controlled dose of the substance. A method for administering a controlled dose to a subject is also described.

Growing community of inventors

White Bear Lake, MN, United States of America

Nicholas C Miller