The present invention provides a safety device for injection needle, which is fitted onto the needle of a syringe, and the needle comprises a needle base and a needle body. The safety device for injection needle comprises a telescopic barrel unit, a first joining part and a second joining part. The barrel unit comprises a connecting end and a deformable end which may be deformed by an external force to be opened and closed, and has two opposite portions. The first joining part and the second joining part are respectively configured at the two opposite portions of the deformable end, which may be detachably fitted to keep the deformable end portion closed or define an opening. The needle body may be fitted and covered within the barrel unit while the barrel unit is extended, and may be passed through the opening of the deformable end while the barrel unit is retracted. Thus, the present invention may provide a safety device for injection needle, which needs not to be detached and reduces the stabbing risk.一種注射針頭之安全裝置,用於套覆一針筒的針頭,該針頭包含一針座及一針體,該注射針頭之安全裝置包含一可伸縮的套筒單元、一第一結合件及一第二結合件。該套筒單元包括一連接端部以及一可受外力變形而啟閉且具有二相對部位的可變形端部。該第一結合件及該第二結合件分別設置於該可變形端部的二相對部位,可分離地相配合而使該可變形端部維持封閉或定義出一開口。該套筒單元展開時可使該針體被套覆於該套筒單元中,而收縮時可使該針體穿過該可變形端部的開口。藉此可提供一種免拆卸、可減少針扎危險的注射針頭之安全裝置。2...針頭21...針座22...針體3...套筒單元31...基座筒311...連接端部312...環形定位槽313...導引槽32...中間筒321...定位端部322...定位針孔323...環形定位槽324...第二卡槽325...第二卡條326...定位環327...導引件328...導引槽33...終端筒331...可變形端部331a、331b...兩相對部位332...開口333...定位環334...導引件4...第一結合件41...第一卡槽5...第二結合件51...第一卡條
