Patent ID: 8556131

Claim:
A fluid dispenser comprising: a fluid reservoir of variable working volume, in which the reservoir fluid is protected from the air, a wall of the reservoir is an actuator wall that is axially movable down and up between a rest position and a depressed position, the movement of the wall causing the pressure in the reservoir to vary, the wall being situated at an end of the dispenser; and a dispenser orifice via which the fluid is dispensed, the orifice being provided with an outlet valve; the actuator wall is in direct contact with the fluid in the reservoir; and the reservoir forms a slide cylinder in which there is engaged a follower piston that is configured to slide in a leaktight manner in the cylinder, wherein the actuator wall and the follower piston move along a common axis X, and the follower piston remains static with respect to the cylinder during dispensing and moves with respect to the cylinder when the pressure on the actuator wall is released, wherein the orifice is situated at an end of the dispenser other than the end at which the actuator wall is situated, and wherein the follower piston forms a connection duct that puts the reservoir into communication with the dispenser orifice.