| July/August 1992

Recently we received a very interesting letter from Mr. J. Vegter, Hoofdweg 107, 9628 CM, Siddeburen, Holland. Mr. Vegter points out that many of the oil engines which use the so-called Hvid fuel system are really misnamed. To paraphrase Mr. Vegter, 'Mr. Jan Brons from Holland is the inventor of this fuel system, and he built engines with this system from 1904 to 1937. Later, Brons built other gas and diesel engines until Waukesha Engine Division took over the [Brons] factory on January 6, 1989.

'Brons received a German patent on his fuel system on April 19, 1904 under No. 167149. An improved system was patented in Germany under No. 190914 of April 2, 1906. The reason Brons got a German patent was that Holland did not have a patent system at that time.

'Jan Brons sold a license to the R. M. Hvid Company on January 1915. Already in 1909, Laurin & Klement A.G. of Austria had acquired manufacturing rights, followed by the sale of Danish rights in 1910 and Norwegian rights in 1912. Brons sold license rights to many other engine manufacturers, including Deutz at Cologne, Germany. The latter sold many Deutz Brons engines between 1907 and 1930. It also appears that Daihatsu Company of Japan acquired subsidiary rights from R.M. Hvid Company in 1922. The Brons factory built many different styles of this oil engine, including a marine model with air starting.'

Mr. Vegter writes that he worked at the Brons factory, and when Waukesha took over, he purchased all the old Brons office material, photos, hand-books, customer books, and a lot of spare parts. He indicates that he may even start a little museum about Brons.

We commend Mr. Vegter for his efforts in preserving much of the Brons material, and for shedding some light on the connection between Brons and the R.M. Hvid Company. We fully agree that perhaps Hvid has received far too much credit regarding the Brons system, since they (Hvid) were merely licensees of the Brons patents. We're not sure on this point, but perhaps there were some other legal issues involved that are now clouded by time.

For those unfamiliar with the Brons or Hvid system, depending on which term you prefer, there were a substantial number of these engines built in the United States. All are of the compression ignition type, and the best known is the Thermoil, built by Hercules and sold by Sears & Roebuck. These engines all have some common features. The so-called injector is really not an injector at all. It consists of a heavy steel block containing a small poppet valve. In most instances, the valve seat has a small hole drilled in its periphery. A long slender needle valve is seated above this tiny hole. It is controlled by the governor, and regulates the amount of fuel that can get through when the poppet valve opens. The fuel is deposited by gravity into a small cup below the poppet valve. It has two or three small holes toward its bottom, and these holes are aimed toward the piston head. On compression, the air temperature rises sufficiently within the cup to detonate the light parts of the fuel. The subsequent chain reaction forcibly drives the remaining fuel from the cup into the heated air and ignition continues.