 Wankel engine
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| Wankel engine in the Ro 80 from 1969 |
Starting in 1960, Felix Wankel's fascinating kinematics promised an end to the piston's pounding back and forth. A rotary piston no longer needs to be decelerated to 0 km/h and then accelerated to 80 km/h. And apart from
the eccentric shaft, there is only one moving part per chamber.
The automotive industry, which was poor in developments at the time, pounced on this invention. Almost all manufacturers took out licenses, built prototypes, and were impressed by the relatively compact design and quiet
operation. Instead of cylinders in which pistons move linearly, the Wankel engine has one or more chambers.
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In these, a triangular piston with slightly outwardly curved sides is mounted on an eccentric part of a shaft, but at the same time is connected to a stationary gear by a gearing. It doesn't simply rotate with the shaft; the
gearing requires it to make a certain backward movement. As a result, it only makes one rotation for every three rotations of its shaft.
The purpose of these revolutions is to draw in the air-fuel mixture through the upper right slot, compress it, and expel it again through the lower right slot after combustion, once every third rotation of the piston, i.e., every full
revolution of the eccentric shaft. For this reason, it is considered a two-stroke rather than a four-stroke engine. An ingenious mechanism in which there are no reversal points for the piston.
Unfortunately, lubricating and sealing the piston in its housing is difficult. However, this problem was solved sufficiently much later by Mazda. NSU had already attempted to address the elongated combustion chamber with
two spark plugs. Proof of the engine's performance was a victory at the 24 Hours of Le Mans. However, the engine was affected by emissions regulations far too early.
The unfavorable exhaust emissions and high fuel consumption are attributed to the extremely unfavorable combustion chamber shape. However, if the engine, also known as the rotary piston engine or the rotary engine,
had undergone as long a development as the reciprocating piston engine, we would probably only know it today. Mazda, too, failed to tackle the fuel consumption and thus environmental problem despite decades of
development.
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| 1991 A rotary engine wins the 24 Hours of Le Mans. |
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