How does a platform lift work?

You’d be forgiven for thinking that the mechanism for making a platform lift go up and down would be simple. The truth is actually far from simple. Platform lifts come in three main drive systems, each suited to different specifications, and each having their own individual advantages and disadvantages.

Modern platform lifts are operated using electronic controls which send signals to a central processor unit. This unit initiates the motors or pumps to move the platform between levels.

Hydraulic Drive System

For this system, a lift platform is attached to a hydraulic ram. The ram moves the lift by pushing hydraulic fluid, via a pump from a central reservoir, into the ram. The pressure extends the ram and causes the lift to rise. The flow is reversed to lower the lift.

There are some disadvantages to this system. The pump and reservoir mechanism require extra space, and the hydraulic fluid can sometimes give off an odour in hot weather.

Screw and Nut Drive System

This lift system utilises a steel screw pole which runs the length of the shaft. A motor on the platform drives a nut attached to the screw. When the motor turns the nut in one direction the lift will rise, reversing the turning direction of the motor will cause the lift to descend.

Installing a screw and nut system often requires a supporting wall, especially on longer travel lifts, in order to stabilise the unit. The thread on the screw and drive nut is susceptible to wear and tear so requires routine lubrication – often done by a self-lubricating system.

Encapsulated Chain Drive System

This chain operated system is encased in a highly durable polyurethane plastic casing. This casing guides the chain to ensure slippage is virtually impossible.

A motor and gearbox are fitted to the top of the shaft. The motor turns a driveshaft that attach to the platform. As the driveshaft rotates, the platform is lifted or lowered. The durability of these platform lifts mean a much longer guarantee can be given on the drive system.