Insertion / retraction mechanisms for drug delivery devices are disclosed. The insertion / retraction mechanism includes a retreat hub, an insertion hub, an insertion / retraction mechanism housing, and a double torsion spring system. The retreat hub includes a first primary rotation stop portion and a second primary rotation stop portion extending radially inward from the inner surface. The insertion hub is located inside the retracting hub and includes a first complementary rotation stop and a second complementary rotation stop extending radially outward from the outer surface. The double torsion spring system selectively engages the first primary rotation stop and the second primary rotation stop with the first complementary rotation stop and the secondary rotation stop, respectively, and further inserts / inserts / Rotate the retracting hub with respect to the insertion / retracting mechanism housing as the retracting mechanism moves between the initial position, the insertion position and the retracting position.薬物送達デバイス用の挿入／後退機構が開示される。挿入／後退機構は、後退ハブと、挿入ハブと、挿入／後退機構ハウジングと、二重ねじりばねシステムと、を含む。後退ハブは、内部表面から径方向内側に延びる第１の一次回転停止部及び第２の一次回転停止部を含む。挿入ハブは後退ハブの内部に配置されており、外部表面から径方向外側に延びる第１の相補形回転停止部及び第２の相補形回転停止部を含む。二重ねじりばねシステムは、第１の一次回転停止部及び第２の一次回転停止部を第１の相補形回転停止部及び二次回転停止部にそれぞれ選択的に係合させ、更に、挿入／後退機構が初期位置と挿入位置と後退位置との間で動く際に後退ハブを挿入／後退機構ハウジングに対して回転させる。
