
Charles
Yale Knight born in Salem Indiana in 1868 was a journalist and
a printer working for the Minneapolis Tribune. He then moved
to Chicago and founded the magazine Dairy Produce in 1894. In
1901 he bought the 15th 'Waterless Knox' but found the air cooled
engine very noisy. A couple of years later he bought a 'Searchmont'
auto very cheaply, after the collapse of the company, but found
it prone to valve spring breakages. These two events led Knight
to start a quest for a silent engine without the problem of
poppet valve and their associated problems. Recalling his youth
he remembered repairing the slide valve mechanism on his father's
steam driven saw mill. Financed by a Chicago merchant named
Lyman Bernard Kilbourne, he began experiments with slide valve
engines. By 1904 he had devised an engine in which the piston
was surrounded by double concentric sleeves, whose rise and
fall was controlled by a subsidiary crankshaft. Slots cut in
the walls of these sleeves coincided with the inlet and exhaust
ports in the cylinder walls. The top of the cylinder walls and
the top of the cylinder was sealed by a separate cylinder head,
which without the need to accommodate poppet valves could have
an uninterrupted hemispherical combustion chamber, with the
spark plug at its apex- a near ideal configuration. Since all
moving parts slid on a film of lubricant and there were no impact
members, as in a conventional engine, this resulted in great
mechanical silence. Knight's double sleeve valve engine was
finished in October 1904, it was a 2523cc four cylinder unit
which was installed in a Panhard type car - actually his 'Searchmont'
At the time the American car industry was selling all the cars
they could manufacture and so Knight could not interest them
in taking up the rights to his engine, as this would involve
them in the cost of introducing a new engine. Although 38 cars
were built during 1907 using chassis supplied by Garford ( also
responsible for the first - petrol driven Studebakers) there
were comments from the general public who when they saw them
said, 'they rolled along the streets quiet and smooth like rubber
balls'. Mr Manville chairman of the Daimler board heard about
the 'Silent Knight' and was very interested, at the time they
were feeling very threatened by Napier who had high kudos in
the Daimler luxury market, so it was that Daimler developed
the Silent Knight. They used this engine in their vehicles for
many years, production finally ceased due to the engines' heavier
weight and habit of producing a trail of smoke! Of course the
further development of the poppet valve engine which had become
more reliable and quieter aided its demise. |
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