Geared traction elevators use a worm and worm gear type reduction unit to allow precise control of position. Which option best describes this component?

Geared traction elevators use a worm and worm gear type reduction unit to allow precise control of position. Which option best describes this component?

• A. Belt Driven System
• B. Worm and Worm Gear Type Reduction Unit
• C. Gearless Drive
• D. Hydraulic Ram

Answer: (B)

The key idea is that this reduction unit uses a worm and worm gear to multiply torque and control speed in a compact, precise way. A worm gear provides a high reduction ratio in a relatively small space, which lets the motor run at a convenient speed while delivering the low-speed, high-torque motion needed to move the elevator car smoothly. Importantly, the worm gear often offers self-locking behavior, meaning the load helps hold the car in place and resists back-driving when the motor isn’t actively powered. This makes precise positioning and stable stopping much easier, which is essential for geared traction systems. Other drive concepts—belt-driven systems, gearless drives, or hydraulic rams—don’t describe this specific reduction unit used for precise control in geared traction elevators.

The key idea is that this reduction unit uses a worm and worm gear to multiply torque and control speed in a compact, precise way. A worm gear provides a high reduction ratio in a relatively small space, which lets the motor run at a convenient speed while delivering the low-speed, high-torque motion needed to move the elevator car smoothly. Importantly, the worm gear often offers self-locking behavior, meaning the load helps hold the car in place and resists back-driving when the motor isn’t actively powered. This makes precise positioning and stable stopping much easier, which is essential for geared traction systems. Other drive concepts—belt-driven systems, gearless drives, or hydraulic rams—don’t describe this specific reduction unit used for precise control in geared traction elevators.