The Washington times., 1918-10-12

which is known as a shackle. The
spring leaves are fastened together
usually by means OF bolt. located
at the center of the spring.
The action OF the spring makes
necessary a certain amount of fieNi-
bility in its attachment When the
weight OF the car presses down on
the spring. the latter flattens out
and its ends are pushed out beyond
their position when at rest. To-
enable the spring to make this
eIonEation, the shackles are used.
All this creates a delicate prob
lem in spring design. The requi-
site iexibiIity OF the spring must
be determined to a nicely. II the
spring has too much rebound, the
body of the car will be flung vio-
lentIy into the air, and indeed this
was a frequent happening in the
early days Of spring design. before
the proper limits OF flexibility had
been determined. On the other
hand there must be enough re-
bound to cushion the superstruc-
ture against the shocks of road
travel. ExperieQce. however. has
taught our designers to lengthen
the spring and improve its quality
by the use of alloy steels. so that
Ia nice mean OF fleNibility and
strength has been reached. The
spring Of today has fiexibility
enough TO make the car comfort
able and yet is strong enough to
bear its burden without breaking.
1t is to be noticed that the latest
tendencies in spring design make
the part long and fiat, instead OF
deeply concave, as used to be the
case. This new construction dis
c6urages rebound without losing
the necessary fieNibility. Practical
" every type OF spring in use to-
day is giving excellent results.
Semi-elIiptics, when properly de-
signed for the load they must
carry, are strong and flexible.
Three-quarter elliptics have a bit
more 1exibility and a somewhat
greater rebound factor, while full
elliptics have a strong tendency
to rebound. The cantilever type
has achieved some little popularity
in the past year or two, with its
great strength and absence OF re-
bound, but lacking something in
fiexibility.
1t scarcely needs telling that
springs require some sort Of at
tention to help them continue to
fulfill their appointed functions.
The most important attention
called for is the fabrication of the
shackle belts on the ends OF the
springs. This Is provided for by
a grease cup on each location, and
these should be religiously turned
down every day.
The shackles are in motion all
the time and without due lubrica-
ton rapid wear will take place.
Water is very likely to work its
way between the leaves OF the
spring and cause rusting, which IL
fatal to spring efficiency. II is
a good plan to meet this danger by
employing one OF the spring oilers,
of which there are a number on the
market, TO keep the leaf surfaces
covered with oil. The commonest
way OF handling the matter Is to
ply the leaves apart once a season
or so and grease them thoroughly.
Clips are used for holding the
spring to the axle. and these clips
must be frightened every once in
a while. In the case OF a new
car. the spring clips ought to be
frightened up after the first hun
dred or so miles OF running. II
this precaution is not taken the
clip may sag. permitting the
spring to bump against the axle
and cause a fracture. In many
types of construction the place
where the spring rests oscillates,
and when so, IL is important to
give adequate fabrication. A grease
cup is used for this purpose, and
it should be turned down every
day.