Tappet pump, mainly for cosmetic products

A tappet pump comprising a pump body in which a dosage chamber is defined, which communicates with a suction duct by means of a check valve, characterised in that it includes a piston which slides inside the said body to form a moving part of the said chamber, a tappet fitted with a central rod forming a valve, where the said rod is axially mobile inside an axial channel arranged inside the said piston and opening out into the said chamber;

• in that the said rod has one free end arranged in order to block the said channel in the proximity of its communication hole with the said chamber;
• in that the said piston and the said tappet are coupled unidirectionally by interdependent limit stops;
• in that an elastic implement exerts its force on the said tappet and on the said piston by means of the said unidirectional link, in a direction that tends to increase the volume of the said dosage chamber;
• in that the said tappet includes an activation limit stop on one end of the said piston, which is farthest from the latter when the said piston is in its normal position, arranged in such a way that the said piston can only be activated by the said tappet when the said free end of the said central rod is outside the said channel;
• in that the said elastic implement is a coil spring installed between and in contact with the said pump body and the said tappet;
• and in that said coil spring is disposed outside said dosage chamber.