A positive pressure needle-free injection precision infusion set upper cover device (100), comprising an upper cover (1) and an elastic sealing component (2), the upper cover (1) being provided with a drug addition tube (11), an infusion tube (12) and an air guide tube (13) in an upwardly protruding manner, the drug addition tube (11) being provided with a needleless injection interface portion (111), an outer end of the needleless injection interface portion (111) being provided with an injector interface (1111) matching a needleless injector (I), the elastic sealing component (2) being provided with a pressure-bearing head (21), a pressure-actuated body (22) and a pressure-bearing base (23), the pressure-bearing head (21) being provided with a sealing portion (211) sealing the injector interface (1111). When an injection is finished and the needleless injector (I) is removed from the injector interface (1111), the shape of the elastic sealing component (2), having been deformed by bearing pressure, elastically returns to the original shape and produces a liquid volume difference relative to when bearing pressure, and the liquid volume difference creates a positive pressure for a liquid to flow towards an injection fluid inner inlet (117).La présente invention concerne un dispositif à couvercle supérieur pour un ensemble de perfusion de précision pour injection sans aiguille par pression positive (100), comprenant un couvercle supérieur (1) et un élément détanchéité élastique (2), le couvercle supérieur (1) étant pourvu dun tube daddition de médicament (11), dun tube de perfusion (12) et dun tube de guidage dair (13) dans une manière faisant saillie vers le haut, le tube daddition de médicament (11) étant pourvu dune partie dinterface dinjection sans aiguille (111), une extrémité extérieure de la partie dinterface dinjection sans aiguille (111) étant munie dune interface dinjecteur (1111) adaptant un injecteur sans aiguille, (I), lélément détanchéité élastique (2)
