File this one under over-engineered.
Bayerische Motoren Werke, better known as BMW, has come up with some eyebrow-raising concepts and engine ideas before. But this one is certainly far out. Bimmer has reportedly filed a patent for a hybrid system that features two separate-but-equal petrol powered two-cylinder engines, PLUS an electric motor. Those crazy Germans, always making things so… complicated.
The idea behind this patent is that BMW thinks it can get away with a single two-cylinder engine and an electric engine most of the time. But, should you need more power, the secondary engine kicks in. It is sort of like Chrysler’s cylinder deactivation technology, but instead of shutting off fuel to several cylinders, the system shuts down an entire engine. An electric motor presumably provides power at low speeds, with the two banger(s) taking over at highway speeds.
This “split-engine” system seems needlessly complicated to me, but I can see one potentially huge boon to this system. If BMW alternates which engines gets used, I imagine it would spread out the mileage, and thus the wear and tear on the engines, doubling the lifespan and service intervals of both motors. Of course it also means you have two engines to check out should something go wrong. Sounds… expensive. Still, BMW has a lot of experience with two-cylinder engines thanks to their rather extensive motorcycle division.
Keep your eyes peeled for a tri-engine BMW concept in the future, and view the full patent here.
Source: BimmerFile
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About Christopher DeMorro
Check out U.S. Patent No.7,080,6222 B1 issued in July, 2006. The idea of two engines connected in tandem via a clutch has been the main subject of study and research be Belloso Motor Company of Salisbury, MD. Both engines are fueled and run for acceleration, then only one engine is operated for cruising, resulting in fast acceleration and economical cruising. For more details, check out bellosomotors.com. G. Belloso, inventor.