FIELD: device for locking rods of hydraulic jacks. SUBSTANCE: proposed device includes working rod extension chamber and rod retraction chamber, return valve with spring mounted in liquid supply loop; proposed device consists of separate hydraulic unit through which working fluid is fed to chamber. Besides that, device is additionally provided with safety return valve with spring separated from primary valve by sluice chamber; each valve is received by one of end holes used for supply of fluid to one of chambers of hydraulic jack; valves are fitted in way of flow of working fluid to chamber; proposed device is also provided with units for separate closing of safety valve relative to closing of primary valve and unit for control of opening of safety valve. EFFECT: enhanced reliability. 21 cl, 6 dwg
