Patent ID: 8733089

Claim:
A fluid-dynamic circuit comprising: (a) a source of a pressurized fluid; (b) distributor valve means arranged for distributing said pressurized fluid to transport lines; (c) a feeding line of said pressurized fluid arranged between said source and said distributor valve means; (d) at least a main user apparatus which is movably actuated by actuating means which comprise a slider slidingly and sealingly fitted in a sliding seat of a containing element which is divided by the slider into a first chamber and a second chamber reciprocally opposed and both having variable volumes; and (e) at least a second and a third transport lines of said pressurized fluid interposed between said distributing valve means and said first chamber and second chamber respectively, wherein between said valve means and at least one of said second and third transport lines a first derived transport line is arranged along which quick discharge means normally closed and having an actuatable opening by actuating means are mounted, and wherein said quick discharging means comprise a second slide valve having two working positions and three access ports, a first port being connected to said first derived transport line, a second port being connected to a quick discharge, a third port being connected to one of said second and third transport lines, said slide valve being maintained in a position in which said second port is maintained normally closed by contrast elastic means.