The utility model relates to a needle-free medicine adding device, which is used for solving the problem that the elastic sealing plug conventionally used for the needle-free medicine adding device has a poor rebound effect after being compressed. The elastic sealing plug system comprises: a stop disc having a first surface and a second surface opposite to each other； a first end of a valve stem is connected to the first surface, and the connecting portion forms a first bending portion And a deformed body, the first end of the deformed body is connected to the second surface, the second end of the deformed body is connected to a guide post, the deformed body has a weakened portion of thin material, and a thick and thin joint portion of the material is formed A second bending portion, the elastic sealing plug is accommodated in a cavity tube combined with a base and an outer cover, the first surface of the stopper disc abuts the shoulder portion of the outer cover, and the guide post It is placed in the guide hole, and the abutting portion abuts on the top surface of the inner wall of the base.一種免針加藥裝置，用以解決習知用於免針加藥裝置之彈性密封塞受壓後回彈效果不佳的問題。該彈性密封塞係包含：一擋止盤，具有相對的一第一面及一第二面；一閥柱之第一端連接於該第一面，該連接部位係形成一第一折彎部；及一變形體，該變形體的第一端連接該第二面，該變形體的第二端連接一導柱，該變形體具有一材料較薄的弱化部，及該材料厚薄接合部位形成一第二折彎部，該彈性密封塞容置於由一底座與一外蓋結合之一腔筒中，該擋止盤的該第一面抵接於該外蓋的該肩部，該導柱置於該導孔，且該抵接部抵接於該底座的內壁頂面。
