Enhanced eductor design
Inventors
Stedman, Benjamin • Kakade, Prashant • Woehler, Darrell • Leonard, John
Assignees
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Publication Number
US-9227030-B2
Publication Date
2016-01-05
Expiration Date
Abstract
The present invention provides for an enhanced eductor element that significantly increases the amount of pressure generated at the siphon tube without significantly increasing the flow resistance through the eductor. The invention further provides for breath-actuated inhalation devices comprising the enhanced eductor element as an actuation mechanism.
Core Innovation
The invention describes an enhanced eductor element for a breath-actuated inhalation device, including a medicament flow path and an eductor element having a generally smooth continuous curvilinear surface forming a hollow bore. The hollow bore extends from an inlet to an outlet, and the conduit includes a constriction zone formed by a reduction in the diameter of a portion of the hollow bore. The constriction zone has a length (L_CZ) along the main axis of the eductor and a radius (R), where the constriction zone diameter is smaller than the inlet diameter and the outlet diameter.
A modification member is disposed upon the conduit inner surface and within the constriction zone. The modification member is a protrusion having a length (L) along the main axis of the eductor and a height (H), and it locally reduces the constriction zone diameter and cross-sectional area. A siphon channel establishes fluid communication between the conduit outer surface and the conduit inner surface, and the channel is adjacent to or surrounded by the modification member.
This arrangement increases the local velocity of the flow of an inspiratory breath to actuate the breath-actuated inhalation device while maintaining that the conduit is not positioned within the medicament flow path. The document further states increased siphon pressure drop and breath-actuation performance, with eductor pressure drop described as similar while siphon pressure drop is substantially higher.
Claims Coverage
The document includes one independent claim. The inventive coverage centers on a breath-actuated inhalation device with three inventive features: an enhanced eductor element geometry, a siphon channel arrangement, and exclusion of the conduit from the medicament flow path.
Enhanced eductor element with smooth curvilinear constriction and protrusion
A breath-actuated inhalation device comprising a medicament flow path and an enhanced eductor element having a conduit with a generally smooth continuous curvilinear inner surface forming a hollow bore from an inlet to an outlet, wherein the conduit includes a constriction zone with a smaller diameter portion. A modification member disposed upon the conduit inner surface in the constriction zone is a protrusion that locally reduces the constriction zone diameter and cross-sectional area.
Siphon channel adjacent to or surrounded by the protrusion for actuation by increased local velocity
An enhanced eductor element further comprising a siphon channel establishing fluid communication between the conduit outer surface and the conduit inner surface, wherein the channel is adjacent to or surrounded by the modification member; wherein the eductor element increases the local velocity of the flow of an inspiratory breath to actuate the breath-actuated inhalation device.
Conduit not positioned within the medicament flow path
The conduit is not positioned within the medicament flow path in the breath-actuated inhalation device.
Overall, the claim coverage is directed to a breath-actuated inhalation device where an enhanced eductor element with a smooth curvilinear constriction zone and a protrusion modification member cooperates with a siphon channel adjacent to or surrounded by the protrusion to increase local inspiratory-breath flow velocity for actuation, with the conduit excluded from the medicament flow path.
Stated Advantages
The eductor element increases the local velocity of the flow of an inspiratory breath to actuate the breath-actuated inhalation device.
Substantially higher siphon pressure drop without significantly increasing overall eductor flow resistance.
Improved triggering consistency.
Reduced device failure rates during quality testing.
Documented Applications
Breath-actuated pressurized metered dose inhalers (BApMDIs), including an example BApMDI configuration with a TEMPO-style actuator as described.
Interested in licensing this patent?