Abstract: A fluid supply line 13 connects the hydraulic fluid supply pump 11 to the hydraulic balancing pipe 9, and this line 13 is fitted with a solenoid valve 15. Position detectors 17, 18 are installed on the auxiliary arm 4 and on the main arm 3 close to the articulation of the counterweight balancing beam 5. If the main arm 4 is detected to be in its pendular position before the counterweight balancing beam 5 is detected to be in its vertical position, the logic controller 16 controls activation of the solenoid valve 15 in order to add hydraulic fluid to the jack 8 in order to bring the balancing beam 5 in vertical position.

Abstract: A fluid supply line 13 connects the hydraulic fluid supply pump 11 to the hydraulic balancing pipe 9, and this line 13 is fitted with a solenoid valve 15. Position detectors 17, 18 are installed on the auxiliary arm 4 and on the main arm 3 close to the articulation of the counterweight balancing beam 5. If the main arm 4 is detected to be in its pendular position before the counterweight balancing beam 5 is detected to be in its vertical positions the logic controller 16 controls activation of the solenoid valve 15 in order to add hydraulic fluid to the jack 8 in order to bring the balancing beam 5 in vertical position.