HYDRAULIC DRIVE OF SELF-PROPELLED BOOM CRANE Russian patent published in 1997 - IPC

FIELD: materials handling machinery. SUBSTANCE: hydraulic drive of self-propelled boom crane has main pumps 1 and 17 connected to hydraulic motors 7 and 22 and hydraulic cylinders 8 and 21 of crane mechanisms through hydraulically controlled spool valve hydraulic distributors 6 and 20. Hydraulic drive has valve unit 31 with hydraulic accumulator 32 connected at one side with pressure hydraulic line 12 of control units 13 and 14 and connected to pressure hydraulic lines 3 and 19 of main pumps 1 and 17 at other side. It has also emergency pump 25 with hand drive, hydraulic valves, valves, filter and hydraulic lines. Novelty is that two pressure valves 4 and 5 are installed on pressure hydraulic line 3 of main pump 1 in parallel to each other. Hydraulic control line 11 of valve 5 is connected with pressure hydraulic line of control units 13 and 14 and its spring space is connected with drain hydraulic line 15. Pressure hydraulic line 26 of emergency pump 25 is connected with pressure hydraulic line 12 of control units 13 and 14 through check valve 27 and valve 30. EFFECT: enhanced reliability of operation. 2 cl, 1 dwg