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the speed of the motor, to about 20 rpm for a standard ski winding units can be replaced individually. (Doppelmayr
lift. Reducing the motor speed multiplies the torque but also builds direct drive lift installations based on the gearless
ultimately creates mechanical problems with gear reducers. drive concept, although it utilizes a secondary gear reducer.
Gear reducers are anywhere from 5 to 10 percent less The Doppelmayr Direct Drive, or DDD, uses a hermeti-
efficient, consume oil, produce waste oil, and experience cally-sealed water-cooled permanent magnet synchronous
equipment wear that creates a greater risk of mechanical motor. The water cooling eliminates loud fan noise, and
failure. If there is complete failure of the gear box—and the continuous stator windings are encapsulated in special
bearings, gears, and other parts need to be replaced—it can epoxy resin for protection against external influences.)
be not only expensive but time-consuming (it’s not unheard “By eliminating the gear reducer, not only are you getting
of for areas to wait up to a month for replacement parts). rid of a component that is problematic but you’re also losing
This has been an ongoing issue not only with ski lifts less energy because the gear box has a parasitic load, meaning
but also wind turbines and other large industrial applications. it generates heat and noise, both of which result in losses of
The wind turbine industry has engineered a solution that horsepower of up to 5 to 10 percent,” Mauch said.
eliminates opposing forces inherent in combining motors Leitner’s DirectDrive system is coupled directly to the
with primary gear reducers—and Leitner’s DirectDrive bull wheel, meaning there is no energy loss due to noise
borrows from that technology. The system has a low-rpm or heat generated from friction, equating to 100 percent
synchronous motor with an output shaft directly connected torque and greater efficiency of energy use. Direct drive
to the drive sheave. motors are compatible with much higher pole levels. Where
The direct drive mechanism comprises three moving traditional lifts utilize 4- or 6-pole motors, direct drives can
parts—a rotor and two bearings—that move in line with use up to 80-pole motors. When applied to standard 60
the rotational speed of the bull wheel. The rotor is equipped hertz utility power frequency, the result is 20 rpm, thereby
with permanent magnets and the stator (the stationary part eliminating the need for a gear reducer. (Picture in your
of the motor system) has a segmented design, that is, eight mind the blade speed of a wind turbine.)
independent segments with three winding units each. The From an environmental perspective, direct drive systems
require no lubrication oil at all, whereas conventional gear
drive systems can require nearly 100 gallons of oil that has to
be replaced after 6,000 hours of operation (about 4 years)—
All New Premium a cost to the environment and in terms of labor. Direct drive
results in reduced maintenance costs, as much as a $5,000
Digital Signage savings on gear oil plus savings in waste oil handling and
recycling—and an overall more environmentally-friendly lift.
Mark Kramer, lift and electrical maintenance manager at
CPS (Computer Panorama & Copper, says his company’s decision to go with direct drive

Parking Guidance System) was based primarily on the system’s reliability and redundancy
of design.
“There is redundancy in the systems that will allow
iSKI App Service & continued operation even if there is a component failure,”
Kramer said. “It just makes sense for these installations . . .
Interactive Trail Map plus the environmental considerations of a quieter running lift

with no gearbox or gear oil also weighed in on the decision.”

MediaCam 3.0 DIRECT DRIVE, WHERE HAVE YOU BEEN?

(Live Streaming) Direct drive is new to America, but not the world. It’s been

in use for more than two decades. Leitner’s first direct drive
installation was in 1999 for a lift company that serves the
small Italian ski area Gossensass/Colle Isarco. Since then,
the company has built nearly 100 other direct drive lift
installations across the globe.
So why is direct drive only now coming to North America?

44 | NSAA JOURNAL | EARLY WINTER 2018