Patent ID: 7497359

Claim:
A buffered dosing device for a material, comprising: a main chamber formed within a body, the main chamber comprising an annular volume sized to hold more than one dose of the material, wherein the body defines an interior passage through an interior of the annular volume of the main chamber; a dosing chamber sized to hold one dose of the material, in fluidic communication with the main chamber; a shuttle comprising an uppermost portion located within the interior passage of the body and a lower portion located within the dosing chamber, wherein the shuttle is adapted for movement between: (i) a first position in which the material can flow between the main chamber and the dosing chamber; (ii) a second position in which the shuttle is depressed and seals the dosing chamber from the main chamber, and permits the material to exit the dosing chamber; (iii) a third position intermediate the first and second positions, in which no material can flow between the main chamber and the dosing chamber, and no material can escape from the dosing chamber; and a locking mechanism that prevents the shuttle from being moved from the first position to the second position until the locking mechanism is released.