The Richmond palladium and sun-telegram. [volume] (Richmond, Ind.) 1907-1939, 1919-05-17

volving switch. The drum H is made
of an insulating material inserted in
which is the metal segment X having
binding post for connecting wire
to 1t. II now, instead of running
the wire D direct from the coil to the
battery. it be first fastened to this
segment, and a wire be run from the
rotor to the battery, as shown by the
dotted line, no current can flow
through the coil. except when the ro-
tor (which is made to revolve by the
engine). is in contact with the seq
ment. Thus there viii be a series of
sparks only when the rotor and the
segment are in contact.
By fastening the rotor on it's shaft
in such position that it will come
in contact with the hegment at the
moment the piston of the engine has
just completed its compression stroke
the spark will be timed to come at the
correct time.
Instead of running a wire from the
rotor to the battery, the current is al
lowed to travel through the metal of
/ the engine. or ground" In the Ford
cars the cam shaft is carried through
the front of the engine and the rotor
| is fastened to its end Thus the cur
rent will return through this cam
shaft, then its bearing and so through
| the rest of the engine to point where
wire from the battery or magnetic is
fastened to 1t, so as to collect the
current.
The secondary current also returns
through the ground from the spark
plugs. so that there must be a wire
from the coil to the engine to collect
this returning secondary current The
/ manufacturer, however, desiring to
simplify the wiring as much as posi-
bic uses the primary wire running
| from the coil to the timer for this pur-
| poss- To do this the primary and
secondary are connected as shown.
Please note that the connecting of
i the primary and secondary is done
! OILY to save wire. By tracing the
two circuits you will see that even
though connected the primary cannot
run through the secondary circuit,
nor the secondary through the pri-
mary, accepting along the wire from
i the timer to the coil AS the secon-
/ dairy current comes after the primary
is interrupted, the two will not flow
at the same time, and, moreover, when
secondary is flowing the interrupter
points are open, while the primary has
not high enough voltage TO jump
across the spark plug points.
The Condenser
| The moment the interrupter points
open, thus stopping the flow of the
current, the voltage at the points will
build up SO high as to jump across the
space between them. AS it jumps
across a spark will come which will
be SO hot as to soon burn out the
points. Thus we must have some de-
vice to prevent this. For this pur-
pose what is known as a condenser
is used.
Let us see why the voltage is built
up. If We had a long coil of pipe
through which water was flowing at
2 slight pressure, and if at the lar
end We tried to stop the flow of the
water by closing up the opening, we
would find that we would require
quite little effort far more than the
pressure under which the water is
flowing, to stop it. Why? Because
when we stop the water, that at the
opening has the great amount OF
water in back of 1t which must also De
stopped. Now it takes a resistance o,
pressure to step anything which has
! weight from moving. and as the water
at the opening must stop the foot OIL
water just back of it and also the fool
of water in back of that and SO on
YOU can see how the pressure on tbs
water at the opening will become very
great. If we tried to close the open
ing with a piece of cardboard, the
pressure might build up so high as e
burst through this cardboard even
Ixl -. - -,
the flow of the water when at rest
If we were to use technical expires
sion we would say that the pressur.