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Scientific American · May 31st, 1919
· pp. 567.
The deep subway station at Park Place, New York,
showing the escalator system as it will appear when
completed.
The Seventh Avenue subway coming down the west side of
the New York city turns east at Park Place passing under the Post
Office and on to William, where it turns downtown again and eventually
runs under the East River to Brooklyn. In its course across town, it
must run under two existing subways, namely, the Brooklyn Rapid
Transit Subway which runs under Broadway at this point and the old
Interborough Subway which passes under Park Row. This makes it
necessary for the subway at Park Place to descend to a very low level,
and as a consequence passengers who use the Park Place station have a
long climb from the station platform to the street. The actual
vertical distance is 38.5 feet. In other words it is a three-story
climb, a breathless undertaking for many persons.
When the station was planned, provision was made for a
pair of escalators to carry passengers to and from the station
platform. The wells for these escalators were made wide enough to use
the largest type of double-width escalator which would accommodate
three persons abreast on each step. It was thought advisable, however,
to use narrower escalators than these, so that four of them could be
installed. The purpose of this was to provide greater flexibility of
operation; for each could be driven separately and a design was chosen
which would permit of reversing the escalators so that, if desirable,
the majority of them could be operated to carry passengers upward in
the morning rush hours and downward in the evening rush hours or
likewise adapted to handling crowds on special occasions.
There are two well-known types of escalator in common
use, one known as the step type and the other the cleat type. In the
step type, the steps are arranged to run out on the same plane at the
top and bottom of the escalator so as to form platforms for exit from
and entrance to the escalator. The passengers step upon these
platforms from the side and in leaving the escalator there is a
diagonal shunt which would naturally guide a passenger to the side of
the platform. With this type of escalator it is not advisable to have
the passenger step off the end of the moving platform, owing to the
danger of tripping.
Where the cleat type of escalator is installed, entrance
to and exit from the escalator is made directly at the ends. The
traveling cleats which form the steps of the escalator run between a
comb plate which lifts the passenger's feet off the moving cleats, if
for any reason he should not step off the escalator at the exit
point. Owing to the comparatively narrow platforms of the Park Place
station, it was considered inadvisable to have the ordinary step
escalator with side shunt at the exit point, and so a compromise was
effected in the design of an escalator which is of the step type and
yet combines the cleat form of exit and entrance. This is something
decidedly new in escalators. One of these escalators is now being
installed at the Park Place subway, and its operation will be watched
with great interest. If the escalator proves successful, and there is
every reason to believe that it will, other escalators of the same
type will be installed. The steps are 18 inches wide and 16 inches
deep, with 8-inch risers. The surface of the step is formed with deep
cleats running parallel to the direction of the escalator and, as in
the ordinary escalator, the steps run out on a common plane at the top
and bottom to form the entrance and exit platforms, and at these
points there are comb plates with the teeth of the combs projecting
between the cleats of the steps, so that they will automatically lift
the passenger's feet off the step upon the fixed platform.
The escalator which is now being installed and may be in
service by the time this article is published, has a capacity of 3,600
passengers per hour, and it rises at an angle of 30 degrees, running
at the rate of 90 feet per minute. Long experience has proved that a
higher rate than this is apt to cause injury to careless
passengers. While the steps are only 18 inches wide, the space between
handrails is 24 inches wide, so that there is ample room for a single
passenger, but not more than one person can occupy a step at a single
time. Each step is really a platform on which a passenger can stand,
and this is the reason that it is so much deeper than the ordinary
fixed stairway step. A 22-horse power electric motor is used to
operate the escalator, which it does through a worm gear. An electric
brake is automatically put in service when the motor stops running and
is released by the turning on of the motor. The escalator rises 28
feet from the station platform to the mezzanine floor.
At present, traffic conditions at the Park Place subway
station are such that a single escalator will more than accommodate
all the passengers traveling in a single direction. Two escalators
will be ample for all the traffic for many years to come, but looking
into the future, provision has been made for four escalators, and our
artist in the accompanying engraving has given us a picture of the
appearance of this station when the complete equipment is
installed. The fixed stairways, which provide the only means of
ingress and egress at present, are shown in phantom in the engraving.
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