| 摘要 |
<p>Herein proposed are gas safety ball valves (1) in which the opening manoeuvre occurs through a double lifting manoeuvre in the axial direction of the knob (22) for controlling the shutter (7) of the valve (1) and a subsequent rotation of the knob (22) by 90° to open, the closure also possibly occurring directly through simple closure rotation or by previously lifting of the knob (22), wherein during the opening and closing rotation movement the stop projections (32, 33) of the valve (1) slide on sliding segments (37, 38; 37B, 38B) provided in the knob (22) coplanar or flat-like inclined and associated to relative positioning projections (41, 42). A spring (28) i s housed in a chamber between the threaded end (19) of the screw (11) and a chamber (23) of the knob (22) and positioned by means of the same screw (30) fixed in the screw (11).</p> |
