HYDRAULIC SYSTEM OF TAMPING UNIT OF SLEEPER TAMPING MACHINE Russian patent published in 1994 - IPC

FIELD: drives of vibration machines. SUBSTANCE: hydraulic system of tamping unit has permanent pressure source, hydraulic cylinders of pressing-decompressing 4, 5 and 2, 3 correspondingly of external and internal tie tampers, liquid pressure cylinder-converter 9, liquid flux hydraulic distributors 6-8, valves: reduction 14, safety 15, back 10-13; restrictor 16 provided with back valve. Safety valve 15 is disposed in drain duct of hydraulic distributor 6. Back valve 13 is located in the line which connects this hydraulic distributor with rod cavities of hydraulic cylinders 2, 3. Rod cavities of hydraulic cylinders 2, 3 are connected with pressure line 1 through back valve 12. Back valve 10 is built in cylinder-converter 9, which disconnects rod-free cavity of cylinder-converter and rod cavities of hydraulic cylinders 5 and 4, which are connected with rod cavity of the cylinder-converter through restrictor provided with back valve. Restrictor prevents motion of liquid which is displaced from cylinder-converter. Back valve 10 is open under force by piston of cylinder-converter 9 at the end of pass when tie tampers are pressed. EFFECT: improved reliability; improved safety. 2 dwg