Geared traction elevators typically serve mid-rise buildings with speeds normally found between 200 to 500 feet per minute. The geared machine is designed such that the drive sheave is connected to the motor through a gear train. Power from the motor is transmitted to the drive sheave through reduction gears. The geared elevator machine is more prone to wear and tear than the gearless elevators. The machines have a bronze spiral worm gear connected to the hoist motor which drives a bronze ring gear. These gears mesh at very tight clearances.
Maintenance is critical to maintain these tolerances and if bearings fail or wear, so do the gears. This wear causes heat, pitting, rumbling, friction and undesirable noise. Often times this gear wear results in the machine speed having to be reduced to avoid more damage. When considering a modernization, replacement of geared machines is rather common. Newer and/or more reliable models can be refurbished to like-new operation. Many of the older, early designs however do not warrant retaining, as their components are out of date designs and/or have become obsolete. When considering a modernization, we will assess the condition of your machines and make recommendations for refurbishment or replacement, as needed.
Geared winding drum elevators are no longer installed for public passenger use elevators and typically serve mid-rise buildings with speeds between 50 and 150 feet per minute. The geared winding drum elevator machine is designed such that the car and counterweight pulley drums are connected to the motor through a gear train. Power from the motor is transmitted to the winding drums through reduction gears.
The geared winding drum elevator machine is more prone to wear and tear than the gearless elevators. The machines have a bronze worm gear connected to the hoist motor which drives a bronze ring gear. These gears mesh at very tight tolerances. Maintenance is critical to maintain these tolerances and if bearings fail or wear, so do the gears. This wear causes heat, pitting, rumbling, friction and undesirable noise. Often times this gear wear results in the machine speed having to be reduced to avoid more damage.
When considering a traction elevator modernization, replacement of geared winding drum machines is very common. Often these machines are removed and new geared or gearless traction machines are installed. When this is done, a great deal of other building structural work is required. The geared winding drum machine is an outdated design and rarely warrants retention. When considering a modernization, we will assess the condition of your machines and make recommendations for refurbishment or replacement as required.