Needleless syringe comprising an optimized injector-receptacle

A needleless syringe, comprising:

• a body having a downstream end;
• a cylindrical reservoir having opposite ends and housed by the body;
• a movable upstream stopper;
• and
• a movable downstream stopper closing the opposite ends of the cylindrical reservoir and entrapping an active principle, the movable downstream stopper comprising:
• a receptacle disposed at the downstream end of the body, the receptacle having an upstream face and at least two peripheral injection ducts each having inlets, said receptacle bearing via its upstream face against the reservoir, the receptacle further having a blind central bore;
• a driving means for moving the upstream stopper, the downstream stopper, and the active principle,
• wherein a free height of the blind central bore allows the inlets to the peripheral ducts to be uncovered when the downstream stopper is brought into contact with a closed end of the bore of said receptacle through the operation of the driving means, and
• wherein, on the upstream face of the receptacle, each inlet comprises a spot face positioned on the respective injection duct and is connected to a radial channel opening into the blind central bore, and the upstream face of the receptacle comprising a multilobed seal substantially parallel to the edge of the bore and substantially surrounding the inlets to the injection ducts.