Robert Bosch (2)

We must now mention two Bosch-employees, Bosch's master Zähringer and the, still apprentice, Gottlob Honold. The former improved the Bosch-magnet ignition thus, that the moving parts were made distinctly lighter. One spoke of the low-voltage magneto ignition for higher RPMs. Even the first invention from 1898 caused the company to grow distinctly, the second, from 1902, which was the high-voltage ignition by Honold, finally turned them into a large-scale enterprise.

Until 1900 there were still vehicles with the glow-pipe ignition. The uncontrolled ignition was found in the Daimler and Maybach engines, which were intended for motor-vehicles. There must have been an endless number of tests, before all the engine parameters were met and before the, from the outside fired platinum glow-pipe, reliably ignited the fuel-air mixture in the combustion chamber. Too often in the testing phase and also later on, was the ignition too early, resulting in the single-cylinder firing in reverse when crank-starting.

The compression must be calculated thus, that a suitable mixture, given into the glow-pipe and ignited at exactly TDC. This in fact, substantially increased the possible RPMs, compared with the coal-gas four-stroke engine once invented by Otto, which first made this engine, after the conversion to petrol, suitable for motor vehicles. One can assume three or four times higher RPMs (600/min., later 800/min.), which meant a much lower cubic capacity and thus, distinctly less weight. Indeed, since then the problems of wet spark-plugs have been known.

No, this type of ignition couldn't hold it's own for any length of time, even though Daimler believed in it and seemed to want to stick with it. The lantern-oil flame was not weather resistant, nor could it be exactly regulated and sometimes, led to all sorts of fire-risks. Daimler himself, three years before his death, did in fact admit, that an electric ignition was a better solution for the petrol driven motor cars. Carl Benz placed his bets, right from the beginning, on the buzzer ignition, this however would only permit lower RPMs (300/min.) and was beset with all the replacement problems of the disposable batteries.

At that time, the electrics were considered by the, still very few motorists, to be very complicated. Only the, still very young Bosch company appeared to be able to offer more reliable solutions. After the founding of the small company in 1887, they started producing one-off magneto ignitors for the stationary engines of the Deutz Gas-Engine company. In the beginning, it was simply the refining of the break-away low-voltage ignition used by Otto. Over a period of many years they had to make do with only very few orders.

Don't get the idea that motor vehicles were the center of Bosch's interests. On the contrary, later, when the company got really big, the one-sided dependence on this field scared him. Indeed, a number of factors played a role, Stuttgart was simply a very favourable location, they were able to carry out orders reliably and, in this combination not to be taken for granted, the sometimes obstinate desire of the founder, to find the best possible, future-orientated solution.

The motorcycle engine, with it's incredible 1600 RPMs brought the first boost. Instead of the armature (with windings), one of Bosch's employees constucted a pendulum casing, which could keep up with the high RPMs, this was a low-voltage magneto ignition with an altered break-off mechanism. Indeed,it was still heavy and required extensive intervention in the combustion chamber. It was however, a solid construction and thus, the reputation of the Bosch ingnition spread among the motorists of the day. 06/12