.gif)
Dumbwaiter (elevator)
Encyclopedia
Dumbwaiters are small freight elevator
s (or lift
s) intended to carry objects rather than people. Dumbwaiters found within modern structures, including both commercial and private buildings, are often connected between two floors. When they are located in restaurants or in private homes, the lifts generally terminate in a kitchen.
Thomas Jefferson
used one of the world's first dumbwaiters in his mountain home at Monticello, Virginia, to limit the number of servants around the table to one, so that his guests could enjoy more of the view. He is credited by some as its inventor.
A simple dumbwaiter is a movable frame in a shaft, dropped by a rope on a pulley, guided by rails; most dumbwaiters have a shaft, car, and capacity smaller than those of passenger elevators, usually 100 to 1000 lbs. Before electric motors were added in the 1920s, dumbwaiters were controlled manually by ropes on pulleys.
Early 20th-century codes sometimes required fireproof dumbwaiter walls and self-closing fireproof doors and mention features such as buttons to control movement between floors and locks on doors preventing them from opening unless the car is stopped at that floor.
A legal complaint about a Manhattan restaurant's dumbwaiter in 1915, which also mentions that food orders are shouted up and down the shaft, describes its operation and limitations as follows:
More recent dumbwaiters can be more sophisticated, using electric motors, automatic control systems, and custom freight containers of other kinds of elevators. Recently constructed book lift
s in libraries and mail or other freight transports in office towers may be larger than many dumbwaiters in public restaurants and private homes, supporting loads as heavy as 1000 pounds.
codes and, therefore, have features similar to those of passenger elevators. The construction, operation and usage of dumbwaiters varies widely according to country.
Elevator
An elevator is a type of vertical transport equipment that efficiently moves people or goods between floors of a building, vessel or other structures...
s (or lift
Elevator
An elevator is a type of vertical transport equipment that efficiently moves people or goods between floors of a building, vessel or other structures...
s) intended to carry objects rather than people. Dumbwaiters found within modern structures, including both commercial and private buildings, are often connected between two floors. When they are located in restaurants or in private homes, the lifts generally terminate in a kitchen.
Thomas Jefferson
Thomas Jefferson
Thomas Jefferson was the principal author of the United States Declaration of Independence and the Statute of Virginia for Religious Freedom , the third President of the United States and founder of the University of Virginia...
used one of the world's first dumbwaiters in his mountain home at Monticello, Virginia, to limit the number of servants around the table to one, so that his guests could enjoy more of the view. He is credited by some as its inventor.
Description
Early 20th-century codes sometimes required fireproof dumbwaiter walls and self-closing fireproof doors and mention features such as buttons to control movement between floors and locks on doors preventing them from opening unless the car is stopped at that floor.
A legal complaint about a Manhattan restaurant's dumbwaiter in 1915, which also mentions that food orders are shouted up and down the shaft, describes its operation and limitations as follows:
[There is] ... great play between the car of the dumb-waiter and the guides on which it runs, with the result that the running of the car is accompanied by a loud noise. The rope which operates the car of the dumb-waiter runs in a wheel with a very shallow groove, so that the rope is liable to and does at times slip off. ... The car has no shock absorbers at the top, so that when it strikes the top of the shaft or wheel there is a loud report. ... [T]he ropes of the dumb-waiter strike such wall at frequent intervals with a loud report. ... [T]he dumb-waiter is often negligently operated, by running it faster than necessary, and by letting it go down with a sudden fall.
More recent dumbwaiters can be more sophisticated, using electric motors, automatic control systems, and custom freight containers of other kinds of elevators. Recently constructed book lift
Elevator
An elevator is a type of vertical transport equipment that efficiently moves people or goods between floors of a building, vessel or other structures...
s in libraries and mail or other freight transports in office towers may be larger than many dumbwaiters in public restaurants and private homes, supporting loads as heavy as 1000 pounds.
Regulations governing construction and operation
Building codes have regulated the construction and operation of dumbwaiters in parts of North America since the 19th century. Modern dumbwaiters in the United States and Canada must comply with American Society of Mechanical Engineers (ASME)American Society of Mechanical Engineers
The American Society of Mechanical Engineers is a professional body, specifically an engineering society, focused on mechanical engineering....
codes and, therefore, have features similar to those of passenger elevators. The construction, operation and usage of dumbwaiters varies widely according to country.