Patent ID: 7735692

Claim:
A pump dispenser that is connectable to a bottle and is manually operated to pump liquid from the bottle, the pump dispenser comprising: a pump plunger having a tubular length with a center axis that defines mutually perpendicular axial and radial directions relative to the pump dispenser, the pump plunger having a discharge passage that extends axially through the pump plunger; a piston on the pump plunger; a housing receiving the pump plunger for reciprocating movements of the pump plunger between a first charge position and a second discharge position of the pump plunger relative to the housing; an annular ring projecting radially outwardly from the housing; a circular trough formed in a top surface of the annular ring; a vent hole in communication with the circular trough and an interior volume of the bottle; a closure on the housing, the closure being positioned on the housing to close an opening on the bottle that receives the housing when connecting the pump dispenser to the bottle; a cylindrical pump chamber wall extending axially from the closure and extending around the piston, the pump chamber wall defining a pump chamber with an interior volume containing the piston, the pump chamber wall having radially opposite exterior and interior surfaces and the piston engaging in sliding sealing engagement with the pump chamber wall interior surface; a cylindrical exterior wall extending axially from the closure over the pump chamber wall exterior surface and extending around the pump chamber wall exterior surface, the exterior wall defining a cylindrical empty space radially between the pump chamber wall and the exterior wall; and, a vent passage extending through the closure and axially between the pump chamber wall and the exterior wall and in communication with the circular trough.