Components:
DC or AC motor
Shaft directly connected to a brake wheel and driving sheave
Hoist ropes placed around the sheave.
Absence of gears = motor must run at relatively same low speed as the driving sheave.
Economy = not practical to build motors to operate at very low speeds.
Gearless is for medium and high speed elevators, 500 fpm and above (fpm = feet per minute)
Motor HP = ranges 20 to 400 hp.
Passenger service = is the typical usage, capacities of 2000 to 4000 lb, up to 10,000 lb has been built.
Below 500 fpm required = geared machines are used, see next post
Maximum car speeds = 2000 fpm currently
Pros = gearless is quieter, more efficient, less maintenance, longer life
Rise = optimum for greater than 250 ft rise and where smooth high speed operation is desired
Intermediate range of rise and speeds (150-250 ft and 400-500 fpm) = geared and gearless become an option
International elevator companies, may need metric conversions
1kg = 2.2 lb
1 m/s = 198.6 fpm
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