How Do Drive Systems for Lifts Work?

7 May 2016

We have been installing innovative access solutions since 1994, but a question we’re often asked is, ‘How do they work?’ There are a few different platform lift systems that are in common use in the UK, including the hydraulic drive and encapsulated chain drive system, but the Aritco 7000 and Aritco 9000 that we install here at Gartec are both screw and nut drive systems.

 

SCREW AND NUT DRIVE SYSTEM

The screw and nut drive system works by using a steel threaded bar / screw pole running the full vertical length of the lift shaft. Attached to a motor on the lift platform is a drive nut, and this motor turns the nut. Depending on the direction of rotation the lift will then either go up or down the threaded bar.

We will often require there to be a supporting wall or L-Bracket securing point for the installation, especially for lifts designed to travel further, to stabilise the unit.

These units also require routine lubrication of the thread, however the Aritco platform lifts incorporate a self-lubricating system, reducing the amount of maintenance you’ll need to carry out.

 

HYDRAULIC DRIVE SYSTEMS

In these systems, the platform is attached to a hydraulic ram. To move the lift up and down, hydraulic fluid is pushed into or removed from the ram via a pump from a central reservoir, causing it to extend or contract as necessary.

The drawback of hydraulic drive systems is that the pump and reservoir takes up a huge amount of space, often beneath the lift, meaning where space is at a premium the hydraulic drive system might not be appropriate.

They are also quite noisy in comparison to Screw and Nut Drive systems, and the cables generally need replacing every 5 or so years due to stretching.

In hot weather, the hydraulic fluid can also sometimes give off an odour, and will need to be drained and cleaned/changed at points.

 

ENCAPSULATED CHAIN DRIVE SYSTEM

This system operates via a chain that is encased in a polyurethane plastic casing. The chain is often counterweighted and, due to using chains rather than cables, the ‘stretch’ effect is reduced, so chains last around 20 years.

At the top of the shaft is a motor and gearbox and these work together to turn the driveshaft the chain is attached to, lifting or lowering the lift as necessary.

The chain drive and hydraulic systems use cables and chains to support passengers and the car, and have been made famous by the classic ‘drop’ that is associated with failure in lifts.