Metering valve for a metered dose inhaler providing consistent delivery
View Patent ↗The present invention relates to a novel design for a metering valve that provides improved consistency of formulation delivery. Generally, the metering valve includes (a) a valve stem that generally defines a longitudinal axis and includes a body portion having a metering surface, wherein the longitudinal axis and a plane tangential to at least a portion of the metering surface define an angle from about 2° to about 90°; and (b) a valve body having an internal chamber defined at least in part by the body wall and includes a metering portion configured to substantially conform to the metering surface of the valve stem.
1. An aerosol metering valve comprising:
(a) a valve stem that generally defines a longitudinal axis and comprises:
(1) a body portion comprising a proximal end, a distal end, and at least one side surface connecting the proximal end and the distal end and comprising a metering surface, and having a sealing surface adjacent to the metering surface and distant from a stem portion of the valve stem, wherein the longitudinal axis and a plane tangential to at least a portion of the metering surface define an angle from about 2° to about 90°, and
(b) a valve body; and
(c) a metering gasket configured to be able to form a transient, substantially fluid-tight face seal between the valve stem and the sealing portion of the valve body, wherein the longitudinal axis and a plane tangential to at least a portion of the sealing surface define an angle from 30° to 80°.
2. An aerosol metering valve according to claim 1 , wherein the longitudinal axis and a plane tangential to at least a portion of the sealing surface define an angle of at least 35°.
3. An aerosol metering valve according to claim 2 , wherein the longitudinal axis and a plane tangential to at least a portion of the sealing surface define an angle of at least 40°.
4. An aerosol metering valve according to claim 1 , wherein the longitudinal axis and a plane tangential to at least a portion of the sealing surface define an angle of at most 75°.
5. An aerosol metering valve according to claim 3 , wherein the longitudinal axis and a plane tangential to at least a portion of the sealing surface define an angle of at most 70°.
6. An aerosol metering valve according to claim 5 , wherein the sides of the sealing surface in its longitudinal cross-section are substantially straight-edged or straight-edged.
7. An aerosol metering valve according to claim 1 , wherein the metering surface comprises no significant portion aligned parallel or nearly parallel to the longitudinal axis.
8. A metered dose dispensing device comprising an aerosol metering valve according to claim 1 .
9. A metered dose dispensing device according to claim 8 , wherein said metered dose dispensing device is a metered dose inhaler.