Oscillating axle for a lifting device, lifting device comprising such an axle and control method

Abstract

This oscillating axle (3) for a lifting device (1) comprises an axle bridge (5) at the ends of which are mounted two ground connection members (7), an oscillation axis (X3), a left jack (9) and a right jack (11), each jack (9, 11) having a rod (90, 110) in contact with the bridge (5) and a body (92, 112) fixed on a fixed part (13) of a chassis (2) of the lifting device (1), the body (92, 112) forming a chamber (94, 114) in which the rod (90, 110) moves. The axle comprises a hydraulic circuit (15) interconnecting the chambers (92, 112) of the left (9) and right (11) jacks, in which a fluid is present at a given pressure, making it possible to press the rods (90, 110) of the left jack (9) and of the right jack (11) against the bridge (5), and at least one solenoid valve (150, 152) on a branch (15A) of the hydraulic circuit (15) connected to the chamber (94) of the left jack (9), and at least one solenoid valve (154, 156) on a branch (15B) of the hydraulic circuit (15) connected to the chamber (114) of the right jack (11), wherein each of these solenoid valves (150, 152, 154, 156) may be positioned in an open position, in which fluid may flow freely, and a closed position, in which the fluid is trapped in the chamber (94, 114) of the corresponding jack (9, 11). Each of the chambers (94, 114) of the left jack (9) and of the right jack (11) has a pressure sensor (23, 25) designed to measure the pressure of the fluid in each of the chambers (94, 114). Control means (21) are provided to detect a pressure in one of the chambers (94, 114) that is greater than a first threshold, and/or a differential between the pressures in each of the chambers (94, 114) that is greater than a second threshold, so as to detect the blocking of a solenoid valve (150, 152, 154, 156) in the closed position, and to initiate a safety procedure.

Dependencies are inferred from the claim text.