This month we continue reprinting a series that first appeared
in GEM in the March-April 1969 issue. Over the coming months, we
will retrace engine history as presented by Carlton M. Mull. This
segment originally appeared in the May/June 1969 issue of GEM.
In the first installment about the origination of your hobby, it
was stated that man’s imagination led to experiments and
inventions of the internal combustion engine; and how Thomas
Newcomen’s improved steam engine replaced horses to operate the
mine pumps in collieries of England. Also how James Watt further
perfected the open end vertical steam cylinder.
Along in the early part of the nineteenth century, there were
many inventors working on the idea of producing an engine that
would not require a cumbersome boiler. They employed a cylinder and
piston in these experimental engines, but compression and ignition
had not been accomplished. The system that carried over from the
steam engines using atmosphere and vacuum to move the piston in the
cylinder did not work and they could not overcome the difficulty of
scaveing (sic) the combustion area. The mechanical design posed the
greatest problems, as we see many old ideas used in these engines.
Such devices as tried by Huygens in his endeavor to provide
ignition to the power fuel, is an example. He fixed a container on
the underside of the cylinder in which was a combustible material.
This was ignited and he tried to suck this flame into the cylinder
through a port to cause the explosion of the dry fuel. This was an
idea that may have given some later inventors a clue, but it was
never successful.
Chemists had been experimenting with various materials such as
wood, coal and fats to make gas for artificial light. In 1794,
Robert Street endeavored to produce with turpentine, a gas by
evaporating it into an inflammable gas, and combining it with air
on the intake stroke of the piston. This was then ignited by an
external jet flame and was admitted to the combustion space when a
valve was opened by the travel of the piston of his engine. This
engine did show advanced ideas which were fundamental in
design.
It should be mentioned here that an Italian, Alessandro Volta,
in 1776 had demonstrated an electric spark. This was a development
from Franklin’s early discovery of electricity; however, it
required many years of experimenting before electric ignition was
successful.
In 1799, a French engineer, Philippe Lebow, was also
experimenting with coal to make a lighting gas. He had conceived an
idea to use in a cylinder of an engine to drive a piston. His early
description set forth an engine that would have a double acting
piston, and the gas mixture to be fired by an electric spark. He
also suggested in his patent that two pumps for compressing the gas
and a device to create the electric spark be made by running a
generator from the engine shaft. His untimely death undoubtedly
retarded the perfection of the gas engine for many years.
Samuel Brown of England, in 1823, used gas for fuel which was
burned in a cylinder to create a vacuum that drove the piston. His
was a two cylinder engine with piston rods connected to a walking
beam. The cylinders fired alternately, producing power on each
stroke.
Another Englishman, William Barnett, was issued a patent in 1838
for a single cylinder engine with pumps to compress gas and air and
then admitted to the cylinder which was ignited by a gas jet flame
in a hollow portion of the cylinder head. As the ignition flame was
extinguished after each explosion, a second external gas flame lit
the jet through a valve for the next stroke. Barnett’s improved
models of later years provided the fundamental theory for all
future internal combustion engines, as his engines were the first
to compress the fuel in a combustion space in the engine
cylinder.
Upon the merits of Brown’s designs, many patents were
granted in France and England from 1838 to 1860. In this period, we
find such men as Johnson, Dr. Drake, Degraud, Barsanti and
Mattencci. The latter two men built a vertical open cylinder at the
top, with a piston operating a rack and pinion. This design could
have later inspired Dr. N.A. Otto, who also designed a similar
engine.
A Frenchman, J.J.E. Lenoir, in 1862 is credited with the first
successful gas engine to have been used for the generation of
power. Then Otto and Langen of Germany made further progress in
design and the first engine patents were issued in the United
States in 1875.
The interesting details of the design of the Lenoir engine was
the closed cylinder, like a steam engine with a packing gland
around the connecting or piston rod. There was a cross head with a
‘U’ shaped connecting rod to the crank pin bearing. Two
eccentrics, one on each side of the crank pin bearing, were used to
actuate the slide valves in the cylinder intake on one side of the
cylinder and exhaust on the opposite side. Gas was used for fuel,
and mixed with air, then sucked into the combustion chambers at
both ends of the cylinder. These engines fired at both ends of the
cylinder, somewhat on the two stroke principle. Ignition was
derived from a spark coil and hot plugs.
Engines were rated at 6 HP and 20 HP and were built in both
France and England, and a few reached the United States. About 500
were manufactured and some historians mentioned that these engines
were not completely successful, however they met with a wide
application and set a general type, which was followed by gasoline
engine designers for many years.
