Patent ID: 7665923

Claim:
A dispenser for dispensing a substance, comprising: a body defining a variable-volume storage chamber for storing the substance; a dispensing portion connected with the body and defining a compression chamber coupled in fluid communication with the storage chamber for receiving substance therefrom, and an outlet aperture coupled in fluid communication with the compression chamber; a manually-engageable actuator mounted on the dispensing portion and including a manually engageable surface on an external side of the actuator and a compression surface on an internal side of the actuator, wherein the manually engageable surface is manually depressible between first and second positions to actuate the dispenser, and is normally biased in the direction from the second position toward the first position; a one-way valve including an axially-extending valve seat and an axially-extending flexible valve cover seated on the valve seat and defining a normally-closed, axially-extending seam therebetween forming a fluid-tight seal between the valve cover and valve seat, wherein the flexible valve cover is movable relative to the valve seat and the seam is connectable in fluid communication with the outlet aperture to allow the passage of substance through the seam and out of the dispenser; wherein the manually engageable surface is manually depressible between (i) the first position in which the variable-volume storage chamber is in fluid communication with the compression chamber for permitting substance to flow from the variable-volume storage chamber into the compression chamber, and (ii) the second position in which the compression chamber is not in fluid communication with the variable-volume storage chamber and the compression surface extends at least partially into the compression chamber to pressurize the substance within the compression chamber above an opening pressuring of the valve and, in turn, dispense the substance through the normally closed seam of the one-way valve and out of the dispenser; and a substantially annular piston slidably received within the body and forming a substantially fluid-tight seal therebetween, wherein the variable-volume storage chamber is formed between the substantially annular piston and the one-way valve, and the substantially annular piston is movable toward the one-way valve upon dispensing a dosage from the storage chamber to reduce the volume of the storage chamber in an amount approximately equal to the volume of the dose dispensed.