| 摘要 |
The driving mechanism has a tubular housing (10) to be coupled to a control valve (R) and housing an activating cylinder (20) and an activated cylinder (30), cooperating with each other and respectively coupled to a rod (40) of a wheel and to a sealing device (DV) of the control valve (R). The driving mechanism (MA) presents: an inoperative condition, in which the activated cylinder (30) is maintained in a closing position of the control valve (R); a first operative condition, obtained by the manual rotation of the activating cylinder (20) in a first sense and in which the activated cylinder (30) is maintained in a first opening position, until the activating cylinder (20) is manually rotated in an opposite sense, returning the activated cylinder (30) to its closing position; and a second operative condition, obtained by rotation of the activating cylinder (20) in a second sense and in which the activated cylinder (30) reaches a second opening position, from which it is automatically displaced back to its closing position, in a timed manner. |
