Hercules Engine News

By Staff
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If you don’t know how it’s supposed to be pronounced,
the name ‘Hvid’ is a bit of a mouthful. A Danish name, it
is simply pronounced ‘veed.’ Rasmus Martin Hvid was the man
behind the name, and he held three of the five patents related to
the fuel system used on the Thermoil brand engines and their many

Several years ago someone sent to me a copy of an advertisement
for Penmac engines. The ad was from Melchior, Armstrong &
Dessau, New York, N.Y., the exclusive foreign distributors for the
Penmac engines, and the engine illustrated looked identical to the
6 HP and 8 HP Hercules-built Model U Thermoils.

The illustration at left, showing details of a Hvid engine’s
cylinder head, timing gears and injector, appears to have been used
by various companies that produced the Hvid design of
compression-ignition engines. Since most companies were using
identical mechanical features, it’s presumed they simply opted
to take advantage of an available illustration. It’s believed
this illustration originated with Hercules Gas Engine Co., as it
was the first in the U.S. to produce the Hvid engine design.

Just recently an inquiry came from Wayne Butler in New Zealand
concerning a Penmac engine he has. After several e-mails, it has
been determined Wayne’s Penmac is a 3 HP engine produced by the
Ker & Goodwin Machinery Company Ltd. of Brantford, Ontario
Canada. The tag on Wayne’s engine reads; ‘Petroleum Engine
& Manufacturing Co. of New York.’ If you read carefully,
you can see where the Penmac name came from.

In addition to the three patents held by Hvid, there were two
other patents relative to the fuel system used on the Thermoils and
their look-alikes. Jan Brons and Nanno Timmer of the Netherlands
held the first of these two patents for a ‘Hydrocarbon
Engine.’ It was applied for July 3, 1904 and awarded Oct. 22,
1907. Jan Brons held the second patent, which was applied for on
April 13, 1907 and awarded on May 18, 1909.

On Feb. 2, 1912, Rasmus M. Hvid applied for the first of his
patents for an ‘Oil Injection Device for Oil Engines.’ It
was awarded on April 6, 1915. The patent for ‘Means for
Delivering Oil to Oil Burning Engines’ was filed Aug. 16, 1912
and awarded April 6, 1915. The patent for ‘Hydrocarbon Engine
Governor’ was filed on Dec. 16, 1913 and awarded on Dec. 28,
1915. Interestingly, the Sears catalogs note that the first
Thermoil engines were built by Hercules in October 1915, before
this last patent was issued.

Just recently I received a complementary copy of the book Patent
Brons – One Hundred Years Vaporizing Engines by Jan Vegter of the
Netherlands. It is a rather comprehensive book on Brons, Timmer and
Hvid, their patents and the engines built using those patents. It
includes many illustrations of European-built engines and their
applications as well as those built in the U.S. The illustrations
include English language captions, but most of the text is in

In the U.S. and Canada, there were many brands of look alike
engines that fell under the above-mentioned patents. These include
Thermoil, Hercules, Johnny, Victory, Brantford, Burnoil, Dynoil,
Parmaco, Boos, St. Marys, Cummins, Renfrew, Hoag and probably
others. Besides these ‘look-alikes,’ an Evinrude, several
Cummins and other vertical engines using this type of fuel system
were built. An interesting thing about all of these engines is the
literature that accompanied them, for the text and illustrations
are amazingly similar. From what I can determine, Hercules Gas
Engine Co. of Evansville, Ind., was the first to produce Hvid
engines in this part of the world. It must have been people related
to that company that first wrote the text and supplied the
illustrations for the manuals. Included here are illustrations that
are common to the various manuals.

Glenn Karch is a noted authority on Hercules engines.
Contact him at: 20601 Old State Road, Haubstadt, IN 47639, or
e-mail at: glenn.karch@gte.net

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