The Indianapolis times. [volume] (Indianapolis [Ind.]) 1922-1965, 1933-09-22
-DietZ on Science
ELEVATORS IN
RADIO CITY SET
SPEED RECORD
Cars travelling 1900 Feet
Per Minute Fastest
in World.
BY DAVID DIETZ
SeripDs-Howard Science Editor

Rockefeller Center, New York City,
can boast the fastest passenger ele-
vators in the world, according 70
Harold c. Hichock Of the Westing-
house Electric Elevator Company.
TWenty-fOur Of the seventy-five ele-
vators in the main building operate
at a speed Of 200 feet a minute.
During performance tests. some of
the cars were operated at a speed Of
100 feet per minute and city in
spectors have approved the opera
ton Of one Of the cars at 400 feet
per minute.
The elevators, which are Of the
misunderstanding type. travel dis
tances ranging from ACT feet in the
case OF those with the shortest hauls
to no feet for those with the
longest.
Inese latter cars. making stops
only at the first and top floor, can
complete a round trip in ninety-five
seconds. During that time, the ele-
Vator Is In motion about So per cent
O. the time and running at full speed
about 40 per cent of the time.
Six Gables Required
The building IS seventy floors
high. Each of the eight elevators
which rise to the top of the build
ings requires six cables of high
strength steel 1,600 feet in length.
Each cable is 11-16ths of an inch in
diameter. Each car has a rated ca
pacity Of $500 pounds while the
total suspended load amounts to
$500 pounds.
The cars are able TO accelerate or
slow up at the rate Of about
eight feet per second. This means
that to attain a speed of 1900 feet
per minute the car must travel past
six floors. Similarly, it takes the
distance Of six floors to bring the
car from full speed to a stop.
It is obvious therefore that such
high speed elevators are suitable
only for express runs in very tall
buildings. A distance equal to
twelve floors is consumed in bring
ing the elevator from a start to full
speed and from that speed back to
a stop again.
Nonstop Zone Set Up.
In the Rockefeller Center build
ing the high-speed express elevators
pass through a none-stop zone of
fifty-two floors.
The operation Of these high-speed
elevators is virtually automatic. The
attendant has nothing to do once
the car is in motion. He has but
two mechanical functions to per-
form. He operates a toggle switch
which closes the hatch and car
doors.
These doors are power-operated.
Then he pushes a button which de-
termineS the floor at which the ele-
vator is to stop. All the rest is
automatic. As soon as the doors
close. the elevator starts in motion.
attainS its full speed, begins TO slow
up IN due time, and comes to a stop
at the determined floor. When the
car has stopped. the doors auto
matically fly open.
Ray Made Safety Device
A unique safety device upon these
elevators makes it impossible for
the attendant to close the doors
when any one is still in the opening.
This device, known as the "Safe-T-
Ray employs two beams of light.
spaced three feet apart in the open
ing Of the doors. The beams are
focused upon photo-electric cells
at the opposite side.
When a person is in the doorway.
he interrupts the beam of light and
1t fails to reach the photo-electric
cell The cell is connected to relay
apparatus so that the failure of the
light to reach the cell causes an in
terruption in an electric current and
opens a switch making it impossible
10 clOSe tho doors