Patent ID: 7527177

Claim:
A fluid pump ( 100 ; 200 ; 300 ) comprising: a pusher ( 120 ; 220 ; 320 ) comprising: a push wall ( 121 ; 221 ; 321 ) defining a push outside surface ( 1211 ; 2211 ; 3211 ) and an inside surface ( 1212 ; 2212 ; 3212 ); and a peripheral skirt ( 122 ; 222 ; 322 ) which extends from the inside surface of the push wall; a pump chamber ( 1 ) provided with an inlet valve and with an outlet valve; a dispensing orifice ( 125 ; 225 ; 325 ) via which the fluid is dispensed; a main piston ( 136 ; 236 ; 336 ) for causing the volume of the pump chamber to vary; and a differential piston ( 131 , 132 , 133 ; 231 , 232 , 233 ; 331 , 332 , 333 ) that is mounted to move in the pump chamber in response to variation in the pressure in the pump chamber, the differential piston being mounted to move away from the push wall when the pressure increases in the pump chamber; the pusher and the differential piston being mounted to move along an actuating axis (X) which extends substantially perpendicularly to the push wall; and wherein the differential piston is formed integrally with an inlet valve moving member ( 138 ; 238 ; 338 ) which co-operates with an inlet valve seat ( 1161 ; 2161 ; 3161 ); and the inside surface of the skirt forms both a slide cylinder for the differential piston and a swirl system centered on the dispensing orifice, said swirl system being formed as a one-piece integral construction with the skirt of the pusher.