Know Your Elevator
Series 3
Series 3
Basic Safety in Elevators
In the introduction blog, we spoke on myths or perceptions of fear one may have when travelling in an elevator. Why not have some understanding on the basic safeties included in a typical elevator?
Electromechanical safety comes into action whenever one of the elevator ropes slackens and the elevator exceeds a certain established speed.
Elevator safety gear and overspeed governor are critical components that ensure safe and smooth elevator operation.
Safety Gear
Design
Typically consists of:
- Gears or clutches that engage when the elevator exceeds a certain speed (usually 1.5-2 times normal speed).
- Steel wedges or shoes that clamp onto elevator rails, securing the car.
Operation
- When excessive speed is detected, gears/clutches engage, locking safety gear onto rails.
- The elevator car is brought to a controlled stop, preventing free fall.
Overspeed Governor
Function
Monitors and controls elevator speed, preventing overspeed conditions.
Design
Typically consists of:
- Centrifugal governor: Spins with elevator movement, triggering action at excessive speeds.
- Electrical or mechanical sensors: Monitor speed and send signals to a control system.
Operation
- Governor detects excessive speed (usually 115-125% of rated speed).
- Sends signal to control system, triggering:
- Safety gear engagement.
- Power removal from elevator motor.
- Application of brakes.
Additional Safety Features
Brake systems
Apply mechanical or electrical brakes to stop the elevator car.
Position sensors
Monitor elevator location and speed.
Safety brakes
Engage in emergency situations, holding the elevator car in place.
Buffer springs
Absorb energy in case of elevator over-travel.
