The great breakthrough
In 1996 Kone succeeded in bringing about a revolution with the introduction of the MonoSpace: the first rope lift without machine-room in an absolutely classic technical design.
Despite further development of its basic features the MonoSpace has remained unchanged to this day.
Engineers had long dreamt of a rope lift without machine-room: a lift with a compact drive that made the "engine room” superfluous and thereby simplified the erection of buildings, but which also made lift installation and operation cheaper. Initially, all approaches had failed before Kone succeeded with its great leap forward with the first system without a machine-room, the MonoSpace.
The lift integrated many innovations. The most important was the drive "EcoDisc” that was narrower, more compact and quieter than anything previously seen.
Half as much energy needed
The Finnish Kone developer Harri Hakala came up with the idea of using a slow-running synchronous motor that managed with a maximum of 90 rpm, controlled by a frequency converter, meaning the transmission could be eliminated. The only moving part of the drive was the so-called rotor, which combined brake disc, traction sheave and permanent magnets and as a result all in just one part.
"As a result, Kone provided the concept of a drive that operated highly efficiently,” noted lift planner Hans Jappsen. "As a result, there was less waste heat, whose disposal required less effort and energy. "In fact, the first measurements already performed in 1996 showed the EcoDisc needed almost half as much energy with the same motor power. On top of this, it was much smaller than all other previous aggregates.
"With just 200 mm depth, it was possible to install the drive in the shaft head and on the side of the counterweight between the guide rail and shaft wall,” according to Kone training developer Roland Grunenberg, who supported the installation of the first MonoSpace. This made it possible to dispense with the previously needed machine-room. The lift now only needed one room. This was also the origin of the made-up name MonoSpace, meaning a one-room lift.
Another advantage of the new design was and is its lower noise: since the drive was mounted on rockers and attached directly to the guide rails, very little structure-borne sound is transferred to the shaft and building. "Instead, the static and dynamic forces are diverted directly via the guidance rails into the foundation,” explained Grunenberg.
Looking back reveals how inspired Hakala’s approach was: MonoSpace has remained unchanged to this day while the principle of the EcoDisc - synchronous motor with integrated traction sheave - was transferred to all rope lifts of the company. "Even Kone high speed lifts are moved on the same principle,” revealed training developer Grunenberg.
A lot has also happened in the last 20 years: today the MonoSpace can move up to 5 t nominal load; thanks to regenerative feedback, especially energy-efficient lifts can be realised; shortened shaft heads and pits are possible. In addition, customer can choose between countless options and design versions and determine car sizes down to the last centimetre.
Displacement of hydraulic lifts
The distribution of lifts without machine-rooms began the displacement of hydraulic lifts, which had practically been the standard solution for buildings up to five floors. Although cheap to procure, they were relatively expensive in maintenance due to their high energy consumption and oil changes.
On top of this came the machine-room, which made lift retrofitting effectively impossible and involved definite costs in the case of new construction. "Concrete, screed, electrical systems: in total, this was ten to fifteen thousand euros for a room that investors can now use more profitably for living space or working areas,” noted architect Theodor Tiarks from Burgdorf near Hanover, which above all plans commercial buildings.
Setting standards in technology and design
However, it was not very easy for the new technology to prevail. "A rope lift had to have a machine-room for the inspectors from TÜV and also for building owners,” recalled Kone standards manager Thomas Lipphardt. "There were a lot of prejudices. "The company actually had to obtain a special permit before installation of the first lifts in Germany.
"The control cabinet needed a window that allowed a view of the drive in the event of emergency liberation. This was to enable the technician to see whether the motor was also running,” said Lipphardt and smiled. It is one of the many stories related to a lift system, which to this day has set standards in technology and design.