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Free Fall Dangers

Residential elevators currently offer two basic drive systems, hydraulic or gear driven.  Both systems utilize technology that is over 50 years old, and they are still being installed primarily on the basis of their inexpensive cost of manufacture.  A downfall of both of these systems is that they offer a potential risk of free fall.

Hydraulic Drive Systems

• Although hydraulic systems have some freefall protections engineered into their design, they have no ability to stop in the event of complete packing failure resulting in a free fall.  They have no speed monitoring system to activate any safeties or brakes.  (A packing is found at the top of the hydraulic jack and maintains the pressure in the system.)

Gear Box Driven Systems
(Please be advised that all systems, including counterweight traction and machine room-less elevators have the following skeletons in their closets.)

• Free fall in the event of a motor brake failure.  Although gear box driven systems have some freefall protection engineered into their design, they have no ability to sop in the event of a brake failure.  This stems from the fact that they have no speed monitoring system to activate any safeties or brakes.  The motor brake is also found on the high speed shaft of the drive, and make this type of system highly dependant on the electronic control to prevent failure.  Due to this design, these systems become more prone to free fall as the equipment ages.
• Free fall in the event of a gearbox failure.  Due to lack of ability to monitor the speed of descent if a catastrophic gearbox failure occurs, the elevator will free fall.

The Elevator Company has addressed these serious problems and added a level of safety never before seen in residential elevator free fall protection.

Revolution Solution Free Fall Danger Protection

• In the Revolution system, a packing failure is impossible.  No oils or hydraulics are used in this system.

• The Revolution's motor brake is positioned on a low speed shaft, effectively eliminating wear adn offering simpler electronic control.

• In the Revolution system, a catastrophic gearbox failure is impossible.  It does not use a gearbox.  Rather, a permanent magnet AC gearless motor is the heart of it's silent technology.

• The Elevator Company has incorporated a devise usually only seen on commercial elevators - a speed monitoring governor.  this system monitors the actual speed of teh elevator system, and if it travels more than 12% higher than it's programmed speed, it will instantaneously set the brakes.  This sytem uses centrifugal force and is not dependent on the electronic programming.