| 摘要 |
PROBLEM TO BE SOLVED: To allow two members to be easily coupled and scarcely drawn after coupling by forming a protrusion on an inner surface of a coupling part of a barrel on a circumference, forming a releasing space in the protrusion, and forming a groove to be engaged with the protrusion at the coupling part with a barrel of the other member. SOLUTION: Surfaces formed on both ends of a circumferential groove 12 of a chuck 4 are surfaces 12a, 12b in a direction perpendicular to an axis of a barrel 1, and protrusions 10 of a lead tank 2 are brought into surface contact with the surfaces 12a, 12b. That is, surfaces of both the ends of the protrusions 10 of the tank 2 are perpendicular to the axis of the barrel 1. Thus, the surfaces perpendicular to one another are brought into contact with one another to be scarcely drawn (disassembled) after the coupling. Further, conical parts 12 gradually radially reduced toward a rear side are continuously formed at two positions rear of the groove 12 of the chuck 4 to be easily coupled. |
