It was at the suggestion of Mr. H. C. Wiles of Waukesha Motors Company, C.F.R. engine manufacturers, that a suitable instrumentation be adapted to the standard diesel fuel test engine which would eliminate the inherent disadvantage of the indicating mechanisms but give similar results in the way of rating fuels, and yet be simple in operation, rugged, reliable, as well as inexpensive.
The electronic instrumentation developed is used in conjunction with the standard C.F.R. Diesel Fuel testing unit in which a quartz window has been placed in the combustion chamber, a schematic diagram of the instrumentation used, including the apparatus used in the standard method is shown in figure 5. A double-pole, double-throw, switch is included in order that either the electronic or the standard instrumentation may be used. Comparative ratings are thus easily obtained.
The electronic injection indicator consists of a light source, a shutter attached to the injection nozzle, and a phototube whose output is amplified and used to actuate the conventional neon light in the engine flywheel. As the injection nozzle opens, it causes a larger shutter opening thus permitting more light to fall on the phototube. This sudden increase in light causes the neon bulb to flash, indicating that injection has begun.
Copyright 1947
Engine Research Center
University of Wisconsin-Madison