| 摘要 |
PROBLEM TO BE SOLVED: To facilitate the mounting of a needle mounting element, to simply perform injection needle withdrawing operation by as small a force as possible and to safely engage a piston with the needle mounting element while facilitating the mounting of a hub to the needle mounting element. SOLUTION: A stopper part 7 is formed to the inner peripheral part of the insertion hole 4b of the leading end of a syringe and a contact surface 16b is formed in the main body 15a of the needle mounting element 15 attached to the insertion hole 4b so as to freely come into contact with the stopper part 7 in the direction shown by an arrow B and an interference preventing surface 19b is formed in the main body 15a from the contact end surface 16b to the leading end of the main body 15a and an interval L5 is formed between the interference preventing surface 19b and the apex 7c of the stopper part 7. The projection part 22 protruding from the interference preventing surface 19b is formed to the main body 15a and an interval L6 is formed between the projection part 22 and the inner peripheral surface 4c of the insertion hole 4b and a peripheral direction contact surface 7d is formed in the stopper part 7 in a state of block from the revolution and movement in the directions shown by arrows E, F so as to freely come into contact with the projection part 22. |
