PROBLEM TO BE SOLVED: To provide an injection instrument operated stably and making a holder detachable from a syringe.SOLUTION: The injection instrument includes: a syringe 2, which includes an outer cylinder 21 having a cylindrical outer cylindrical main body part 21a and a mouth part 21b provided to the leading end of the outer cylindrical main body part so as to communicate with the outer cylindrical main body part, a gasket 23 sliding through the outer cylinder, and a plunger 24 connected to the gasket and introduced into and led out of the outer cylinder from the rear opening of the outer cylinder a finger resting flange 25 provided as an integrated or separate body with respect to the outer cylindrical main body part in the vicinity of the rear end part of the outer cylindrical main body part, a holder 3 having an inner diameter inserting the outer cylinder in a lumen and mounted in the outer cylinder and having spiral projection 31a formed to the inner surface of the part arranged to the periphery of the mouth part and a locking structure holding a state that the holder 3 is mounted in the outer cylinder and releasing the holding of the holder.COPYRIGHT: (C)2008,JPO&INPIT【課題】安定した操作が行え、ホルダーを注射器から着脱可能とする注射装置を提供する。【解決手段】筒状の外筒本体部21aと、外筒本体部と連通するように外筒本体部の先端に設けられた口部21bとを有する外筒21と、外筒内を摺動可能とするガスケット23と、ガスケットに連結されて外筒の後端開口から外筒内外に入出可能なプランジャー24とを含む注射器2と、外筒本体部の後端部の近傍において外筒本体部と一体または別体として設けられた指掛用フランジ25と、外筒を内腔内に挿入可能とする内径を有し、外筒に装着され、口部の周囲に配置された部分の内面に螺旋突状31aが形成されたホルダー3と、外筒にホルダーが装着された状態を保持可能とし、およびその保持を解除可能とする係止構造とを含むことを特徴とする注射装置。【選択図】図2
