The San Francisco call., 1897-12-19

frames of bronze and antique brass of
beautiful design. The cages, which are
finished in harmony with the sur
roundings, ascend and descend the
shaft with surprising quickness, yet
without the slightest danger to the
passenger or causing the sensation of
nausea which so frequently accom-
panies a ride in oId-styIe elevators.
The lifts in use in the Spreckels build
ing are known as the Crane New Plum
ger Hydraulic Elevator, and We're
built by the Crane Elevator Company
Of Chicago.
When the important question of ele-
vators was under consideration by the
architects of the building the prime
factor of absolute safety and the
greatest speed were regarded as being
Indispensable. The records of the best
known elevators now in use in tall
buildings throughout the country We're
inquired into, the result being that the
Crane New Plunger Hydraulic was Sc
lected as combining all the qualities
which it was desired to obtain. Ne
gotiations were at once entered into
with the Crane Elevator Company, and
the result was contract for the con-
Struction Of the elevators. Now, that
the elevators are in daily use, expert
ence has proved that the judgment dis
played in the selection of this admir-
able lifting appliance was not defective
A description of the principles by
which the Crane elevators are oper-
ated may prove interesting to Call
readers. 1t need hardly be said that
in the modern tall building, the ele-
VatOr has become a much more i'm
portant element than formerly, and
that the best procurable machine is q
necessity. While the standard ma
chimes answered the purpose for build
ings of ordinary height, they were
found to be very defective when ap-
piled to very tall buildings. The first
objection was that the standard ma
chimes required an unusually large
space up through the building. Sec
ondly, the sheaves had to be multiplied
so many more times that the efficiency
of the machine was largely reduced,
and consequently q much greater
amount Of power was required to ac-
complish the same results. After Civ
ing the subject of elevators for tall
buildings considerable attention, the
Crane Elevator Company finally con-
ceived the new plunger type of ele-
vator, which is now recognized by ex-
perts as the best in the world Al
though the machine was originally
gotten up especially for tall buildings,
st has corresponding advantages for all
structures.
The novelty of this elevator consists
in using the power to lift the weight
instead of the load, which weight in
turn lifts the load, the weight being
the plunger. Its simplicity of con-
struction is its chiefest claim. It takes
the minimum amount of cables, having
but one set of cables, and that only
the length of the height of the build
ing, whereas the old vertical elevator
has one set on the machine about twice
the length of the height of the build
ing. The plunger is made of steel, and
should last fifty years. By the con-
struction of the machine, the ordinary
amount of air allowed to get into the
machine escapes without causing
trouble. In many other elevators this
is a source of considerable annoya nee.
from the fact that it is a common
! thing for some machines to make dan
| gerous plunges.
The efficiency of the Crane New
| Plunger Hydraulic Elevator was de-
| mOnstrated recently by tests made in
| the American Tract Society Building,
| New York In the original test, the
| elevator lifted 3,S42 pounds at the rate
| of 286 feet per minute, and 1,500 pounds
| at the rate of GA feet per minute. Sub
| sequently, when it was in good work
ing order, it lifted 5000 pounds at 423
| feet per minute. 1t descended with
| the car empty at the rate of 400 feet
! per minute. Yet, travelling at this as
| tonishing rate of speed, the elevator
was under perfect control, making
| quick and perfect stops in either di-
| rection.
The elevators in the Spreckels build
ing are provided with a speed regulat-
| ing device. which renders accidents
| well-nigh impossible. This regulator is
applied to the operating valves by
which they are closed progressively as
| the pressure is increased, thereby very
nearly equalizing the speed in ascend
ing and descending. The use of this
automatic device has proved to be the
| important feature desired to overcome
a serious defect of all hydraulic ele-
vators, namely, the variation of speed
at different loads.
The automatic stops of the Crane
elevator to bring the car at rest near
the upper and lower limits of it's move
ment, Independent of the hand gear
have been proved by test to operate
| with entire satisfaction. The car is
| lifted by a plunger counterpoise NOV
ing at half the speed of the car in g
| hydraulic cylinder, the bottom of which
is especially constructed as a dash-pot
which the plunger enters as the cal
nears the top of its movement and alb
sOlutely prevents overrunning Of the
car and the consequent striking of the
buffers at such upper limit. In al
high-grade hydraulic elevators it i:
necessary to regulate the speed by
hand when descending with a heavy
| load to prevent striking the lower buf,
fers, unless the automatic stop be 81
set as to lose much time in making the
landing. With the Crane elevator the
lower automatic stop is so efficient thai
it is impossible to strike the lower buf-
fers when the elevators are adjusted
| TO r-11T a+ ta xry,+ ~