Hydraulic lift with counterweight

摘要

The hydraulic lift has a cabin, a counterweight and a differential cylinder, two adjustable hydraulic machines and an electric motor. The size of the counterweight (22) is such that with the cabin (1) empty, it acts as a brake on the lifting movement of the electric motor (30). For the descending motion, the electric motor drives the hydraulic machines (26,28), which are working as pumps. With the cabin loaded, it drives the pump for the lifting movement of the electric motor and brakes for the descending motion. For (1:1) suspension of the counterweight to the cabin, the weight of the counterweight is equal to the mean of the minimum and maximum loads.