The following is a reprint from The Engineer magazine dated
April 15, 1905. Sent to us by Richard Mock, 159 Dirkson Ave., West
Seneca, New York 14224.
Fig 1. illustrates the simple construction and convenient
arrangement of the Bessemer engine, which is manufactured by the
Bessemer Gas Engine Company, Grove City, Pennsylvania. One of the
more noticeable features of this engine is the absence of
mechanically operated valves. The horizontal shaft seen at the side
of the engine is for operating the igniter only. The engine
operates on the two-cycle principle, thus giving an impulse every
second stroke, or one working stroke during each revolution of the
crank shaft. This frequency of the working strokes gives the engine
a steady motion and adapts it to electric lighting and other
service requiring close speed regulation.
The operation of the engine is as follows: During the backward
stroke of the piston, Fig 2, the mixture of air and gas is drawn
into the front end of the cylinder through the port, A, while at
the same time the previous charge is being compressed in the back
end or combustion chamber, B. As soon as the piston completes the
stroke, the charge is ignited and the piston driven forward by the
burning gases. When the piston reaches the end of the stroke in the
direction of the shaft, the exhaust port, C, is opened, and at
about the same time the gas port, D, at the top of the cylinder is
opened, admitting the fresh charge, which was compressed by the
piston during the working stroke.
The incoming charge enters the cylinder under moderate pressure
and drives the burnt gases before it, thus filling the cylinder
very quickly with the fresh mixture. The piston serves as the gas
valve and exhaust valve, thus rendering it unnecessary to provide
valves for accomplishing the admission and exhaust of the charge.
This reduces the number of working parts to the minimum.
The air and gas are drawn into the front end of the cylinder
through the gas valve, E, located beneath the cylinder, Fig. 3
being an enlarged view of this valve. The air enters through the
large annular opening, F, Fig. 3, while the gas is admitted through
a series of small holes or ports, G. The valve, H, when seated
closes the opening, F, and the small ports, G, both being opened
simultaneously by the valve, which is raised by the suction of the
piston. Air enters the valve body through the air pipe, I, Fig. 2,
which is connected with the interior of the bed to avoid drawing in
dust and dirt.
The governor is located in the gas pipe at the side and on a
level with the top of the cylinder, the speed being regulated by
throttling the gas and thus modifying the force of the explosion to
meet the requirements of the load. The cylinder and back cylinder
head are water jacketed, the front head having no jacket, since it
is subjected to the low temperatures due to the slight compression
of the fresh charge or mixture. This engine is provided with a
piston rod, crosshead and guides the same as a steam engine; in
fact, the construction throughout is in accord with the best
practice in steam and gas engine construction.
The stuffing box in the front head is subjected to only moderate
pressures and temperatures, consequently no trouble is experienced
in maintaining a tight and durable joint. The working parts are
enclosed by a neat hood and crank case which not only prevents dust
and dirt from reaching the vital parts, but renders the engine
self-oiling and adapted to making long continuous runs with the
minimum of attention.
The connecting rod is of the marine type and extra heavy. The
pins also are large and provided with means for obtaining ample
lubrication. The main shaft bearings are provided with chain oilers
which insure copious lubrication at all speeds, and at the same
time pre vent any waste of oil.
The piston is oiled by means of a special automatic sight feed
oiler. The piston is very long, thus providing liberal wearing
surfaces and is provided with four wide packing rings. The engine
is not only very simple, but is un usually massive, being designed
for all kinds of service for which gas engines can be employed.