| 摘要 |
The present invention relates to a precompression pump for spraying a liquid, comprising a first inner compression chamber (35) arranged inside a pump body between a valve (21) for closing an orifice (20) for drawing off the liquid in a reservoir bottle, and an orifice (16) for expelling the drawn-off liquid towards a spraying head (11); this chamber being of a volume which can vary by virtue of the fact that it is limited by a working piston (31) carried by a member which can move axially in the said pump body, characterised in that it comprises a second intermediate chamber (37) between the said first chamber (35) and the said expulsion orifice (16), and a precompression system comprising a needle piston (24) mounted inside the said moveable member but outside the said first chamber (35), and elastic means for stressing the said needle piston (24) towards a position blocking the expulsion orifice (16) from which the said needle piston (24) is freed when the liquid is pressurised in the said intermediate chamber (37), and in that the said second chamber (37) has communicating channels arranged longitudinally and distributed annularly in the said moveable member and opening out laterally around the said needle piston (24) in the vicinity of the said expulsion orifice (16). <IMAGE> |
