| 摘要 |
<p>The device (2) has a control ring (25) movably mounted around tubular portions (9, 15) between a first position and a second position, in which the control ring allows a locking unit (24) to move toward an unlocked position. A control button (42a) is mounted on the ring. The control button is moved with respect the control ring between a third position, in which the control button cooperates with the tubular portion to immobilize the control ring in the first position, and a fourth position, in which the control button allows the control ring to move toward the second position.</p> |
