- 2066 Jestha (old course) · 2.5 marks
Short note: Lifts and escalators
Short answer
Lift: mechanical car in shaft for vertical transport, speeds 0.5-2.5 m/s, essential in high-rise. Escalator: moving stair with inclination 30 deg, capacity 4000-9000 persons/hour, used in malls/airports.
Write a short note on lifts and escalators.
Lifts
A lift (elevator) is a mechanical device which carries persons or goods between floors in a vertical shaft by a car moving on guide rails. Main parts: lift car, hoistway (shaft), guide rails, counterweight, wire ropes, traction machine and motor in the machine room (or machine-room-less), control panel, safety gear and buffers, landing doors and a pit. Types include passenger, goods, hospital (bed) and service lifts, with speeds of about 0.5-2.5 m/s depending on the building height. Lifts are essential in high-rise buildings and for disabled persons.
Escalators
An escalator is a moving stair: a continuous chain of steps driven by an electric motor, which carries a large number of people between floors at 0.5-0.65 m/s.
- Inclination 30 degrees (35 degrees max), step width 600, 800 or 1000 mm, capacity 4000-9000 persons/hour.
- Parts: truss, steps, step chain, handrail, comb plate, drive motor, balustrade and safety switches.
- Used in shopping malls, airports, railway stations and metro stations where heavy traffic moves continuously. It occupies more floor area than a lift and needs an emergency stair in addition.
| Point | Lift | Escalator |
|---|---|---|
| Movement | Vertical, in a shaft | Inclined moving steps |
| Capacity | 6-20 persons per trip | 4000-9000 persons/hour |
| Waiting | Waiting time | Continuous, no waiting |
| Space | Small shaft | Large floor opening |
| Suitable for | High-rise buildings, disabled persons | Malls, stations, airports |
✓ Answer checked by Claude Opus 5.5 (high effort)