South Bend news-times. (South Bend, Ind.) 1913-1938, 1919-09-14

But the piston is not free like the
cannot ball: il is tied to a crank on
a shaft, which is a free fit on its
bearings, so IL turns readily by
means Of a connecting rod. When
the piston moves outward. there
fore. it turns the crank. which turns
the 1ywheel on the shaft, and we
get mechanical motion even as we
did from the body muscles. When
the piston has moved as far out as
the crank will permit. the exhaust
valve is opened and as the piston
comes up again under the urging Of
the momentum stored in the fly
wheel the gases are forced out
Draws In New Supply.
Then we open the inlet valve
again, and as the piston comes down.
still under the urging of the fly
wheel, il creates a suction behind it
and draws in a new supply of food
or fuel. Once again the piston
comes up. both valves being closed
and this fuel is compressed. When
IL reaches the top. the com bustion
or rapid chemical action is started
by an electric spark and the cycle
of operations is repeated. You viii
see that 10 takes four strokes of tho
pistOn-two down and two up-to
accomplish the desired result and
we call a motor operating on this
principle a four-stroke cycle motor.
The down strokes are inlet or in
duction. during which the inlet
valve is open. and the power strokes.
l. al
closed. The no strokes are COM
pressions when both valves are
closed and exhaust during which the
exhaust valve is open. To complete
the cycle ii takes two revolutions
Of the crank-shaft, and il will be
seen that each valve opens only
once in this time. To make them
work automatically. therefore. we
place a shaft below them and on
that shaft we place a wheel with
hill on IT," called wheel.
Every time the hill on the cam
comes around. it hits the lower end
OF the valve stem, pushing the valve
up and opening IT, Since we want it
10 do this only once in two revolt
tions. we naturally gear the cam
shaft so Il will rotate only once TO
two revolutions of the crankshaft
Considering crankshaft angular
movement, which amounts TO 100
degrees or two revolutions in the
cycle the exhaust valve opens $40
degrees. or a circle and a half after
the inlet valve opens. Since angular
distances on the camshaft are half
what they are on the crank shaft.
we viii place the little hills on the
tam-shafts 27O degrees. or 3-4 OF
cycle apart.
Oil Takes Place OF Blood.
Next in Importance to the alimen-
re can place any one bodily func-
ton ahead OF the others legitimate
ly-is the blood circulatory system
Here we have a fluid the compost
tion Of which is OF the utmost i'm
portance. circulated TO each and
every part OF the body where wear
occurs. by means Of a pump-the
heart The circuit is continuous. TAX
ing ~ such vital organs as the lungs.
where the blood is brought into con-
tact with pure air and purified: the
kidneys. where il is filtered 70 re-
move certain impurities. and return
ing TO the heart for recirculation.
Its function. broadly. is TO check
wear and remove particles OF mat
ter which tend 70 give rise 10 deter
ioration.
The oil takes the place OF the
blood in the internal combustion en-
gine, and it is every bit as important
40 the correct functioning Of the mo-
tor as is the blood 10 the body. Its
function Is 10 eliminate friction and
wear and remove particles OF mat