Suspension Means: The Great Innovation

“How to gain m2 saving energy and simplify maintenance”

A new era in elevators began a few years ago. With electronics already dominating the direction, stop and priority control system, progress was made in improving the smoothness of the ride and the accuracy of the stop by adding the voltage and frequency converter to the electronic control systems.

Then it was the turn of the traction machine. In this case, the great improvement focused on eliminating the gearbox stage, thus eliminating the mechanical speed reduction system that caused many inconveniences: energy losses in friction and heat, vibrations, noises and oil consumption.

Finally, in these times, the greatest innovation in means of suspension was developed, which led to achieve supremacy in the optimization of safety systems, elevation, control, and now also space.

This element of the elevator is the one that connects the car with the counterweight passing through the machine. These new materials to pull the car are already in use today and have a standard that regulates them, the ASME ANSI A17.6. They are also allowed in Europe and will soon be incorporated in the EN 81 and ISO, as the main means of suspension, displacing the steel cable as an alternative means. These are traction belts and aramid fiber cables.

Aramid fiber is very suitable for equipment that must travel to great heights because it is very light and can also move with small diameter sheaves.

The Invention of the Belts

But the great innovation came with polyurethane-coated traction belts. This means of suspension surpasses everything known as an innovation for the elevator. It is the element that brings together all the previous improvements, to agglutinate in a new elevation system, safer, more comfortable, simple and with great advantages for the constructors.

These belts were invented by Otis a little more than 20 years ago but, due to the expiration of its patent in 2019, there will be a revolution in elevator redesigns without machine room and reduction of hoistway, which will make it the star of the great change in elevator equipment.

The belt allows remote monitoring of the steel cable inside the thermoplastic, with an electronic system located at one of its ends and it constantly evaluates the state of the steel strands, being able to deactivate the equipment at the next stop and inform with an alarm signal its state.

It uses the same construction as the strands of a common steel wire cable but arranged flat. This allows the sheave, complying with the regulation that it must be 40 times the diameter of the wire cable, to be only 86 mm in diameter.

Tests and 20 years of experience in its use indicate that it outperforms cables with the same composition in tensile load and has a much longer lifespan, more than 10,000,000 cycles.

Each cycle is the passage through the traction sheave of the same section of the belt. Therefore, by doing a simple calculation in the use of an elevator in an average residential building, its useful life would exceed 30 years.

The traction belt also made it possible to “gain m² or sq²”. Engineers developed a much smaller, permanent magnet gearless machine that can be placed inside the elevator shaft, which made it possible to design equipment capable of substantially reducing the space for elevators and saving energy, without altering the performance in terms of capacity for people and loads transported.

In addition, the machine rooms were definitively eliminated, allowing to save money and time in their construction or to use them for another purpose. With a good frame or arcade design and using the right elements, elevators will no longer need oil or grease. Is it time for zero-maintenance equipment and safety inspections only?

Finally, these times saw the development of the greatest innovation in means of suspension, which led to achieving supremacy in terms of optimizing safety systems, lifting, control and, now, also space.