Fluid product dispenser

1. An assembly method for assembling a dispenser, wherein the dispenser comprises:

a reservoir containing fluid and air, the reservoir forming an assembly opening;

a fluid dispenser cannula in communication with the reservoir, the dispenser cannula forming a dispenser end; and

an actuator member engaged in the assembly opening, for supplying the dispenser cannula with fluid coming from the reservoir;

wherein the actuator member comprises a deformable membrane that defines an outside face forming a pusher, and an inside face that is in contact with the air of the reservoir, when the dispenser cannula is in contact with the fluid of the reservoir;

wherein the actuator member includes an assembly sleeve that is inserted in sealed manner in the assembly opening of the reservoir;

wherein the assembly sleeve performs one sealed axial stroke in the assembly opening of the reservoir in order to reach its final sealed assembled position, the sealed axial stroke defining a stroke volume Vc; and

wherein the deformable membrane is movable between a rest position and a fully depressed position so as to define, between these two positions, an actuation volume Va that is greater than, or preferably substantially equal to, the stroke volume Vc of the assembly sleeve;

the method comprising the following steps:

a) filling the reservoir with fluid via its assembly opening in the absence of the actuator member;

b) engaging the actuator member in the assembly opening of the reservoir, the deformable membrane being held in its fully depressed position when the assembly sleeve comes into sealed contact with the assembly opening of the reservoir; and

c) while the assembly sleeve is in sealed contact with the assembly opening of the reservoir, releasing the deformable membrane, which thus returns into its rest position.

2. The assembly method according to claim 1 , wherein the dispenser comprises a protective cap that is provided with closure means for closing the dispenser end of the dispenser cannula in sealed manner.

3. The assembly method according to claim 2 , wherein the reservoir and the dispenser cannula are made in the form of a single-piece body that is advantageously made of a transparent material.

4. The assembly method according to claim 1 , comprising the following successive steps:

b1) deforming the deformable membrane into its fully depressed position;

b2) engaging the actuator member in the assembly opening of the reservoir until the assembly sleeve comes into sealed contact with the assembly opening of the reservoir;

c1) releasing the deformable membrane so that it returns into its rest position;

c2) moving the actuator member in the assembly opening of the reservoir, so as to cause the assembly sleeve to slide in sealed manner in the assembly opening until it reaches its final sealed assembled position.

5. The assembly method according to claim 1 , comprising the following successive steps:

b1) deforming the deformable membrane into its fully depressed position;

b2) engaging the actuator member in the assembly opening of the reservoir until the assembly sleeve comes into sealed contact with the assembly opening of the reservoir;

c12) progressively releasing the deformable membrane so that it returns into its rest position as the assembly sleeve slides in sealed manner in the assembly opening, the rest position and the final sealed assembled position advantageously being reached substantially simultaneously.

6. The assembly method according to claim 5 , wherein the axial force necessary to deform the deformable membrane from its rest position into its final sealed assembled position is less than the friction forces between the assembly sleeve and the assembly opening during sealed sliding for reaching the final sealed assembled position.

7. The assembly method according to claim 1 , wherein the dispenser end of the dispenser cannula is closed in sealed manner.

8. The assembly method according to claim 1 , wherein the dispenser is a dropper dispenser.

9. The assembly method according to claim 1 , wherein the dispenser end is configured to form a drop of fluid that separates from the dispenser end by gravity.