The invention discloses a safety prefilled injector. The safety prefilled injector includes an injector main body, a needle and a core bar. The injector main body includes a needle coupling part and a core bar coupling part arranged at two edges. A space is formed in the injector main body and filled with a predetermined dosage of injection solution. The needle includes an injection needle and a plug. The injection needle includes a hole and couples with the plug. The plug is closely attached to the space in the injector main body and adjacent to the needle coupling part so that one edge of the injection needle extends out to the needle coupling part. The core bar includes a head and a tail and closely couples to the space in the injector main space through the head. A force can be applied to tail to push the head moving forward. The head includes a protection film plug. A pulling part is arranged in the head and insulated from the injection solution with the protection film plug. The head can be pushed so that the injection needle breaking the protection film plug. The plug is inserted into the head so that the pulling part couples with the plug. The core bar and is pulled back so that the injection needle is extracted inside the injector main body so that the used injection needle is not exposed outside the safety prefilled injector.本發明揭露一種安全式預充注射器,主要包括:一注射器本體、一針頭及一芯桿。注射器本體具有相對於兩端之一注射針結合部及一芯桿結合部,注射器本體內部形成有一容置空間並填充有一預定劑量之注射劑液。針頭包括一注射針及一膠塞,注射針具有一針孔且穿置結合於膠塞,且膠塞恰緊密結合於該注射器本體之容置空間中鄰近注射針結合部處,使注射針一端由注射器本體之注射針結合部穿出。芯桿具有一頭部及一尾部,係經由其頭部緊迫結合於注射器本體之容置空間內,並可由芯桿之尾部施力使芯桿之頭部推進。頭部裝設有一保護膜膠塞且其內部裝設有一回拉部,回拉部係受到保護膜膠塞隔絕以避免與注射劑液接觸。當芯桿之頭部推進到底使針頭之注射針穿破頭部之保護膜膠塞並進入其內部,同時使針頭之膠塞塞入頭部內使回拉部咬合於針頭之膠塞,再將芯桿連同咬合之針頭往回拉使針頭之注射針縮入注射器本體內部,避免使用完的針頭之注射針暴露在外肇生危險性。100...安全式預充注射器1...注射器本體11...注射針結合部12...芯桿結合部13...容置空間2...針頭21...注射針211...針孔22...膠塞3...芯桿31...頭部311...保護膜膠塞32...尾部33a...回拉嵌片331...嵌腳34...折點4...護套L...注射劑液
