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Mazda patents show rotary engine for range-extended EV

Two years ago, Mazda introduced a fascinating range-extended electric car called the Mazda2 RE Range-Extender. It took an electric Mazda2, and dropped in an itty-bitty 330cc rotary engine. It wasn't the rotary-powered sports car we had hoped for, but it seemed like a unique way to keep the quirky engine alive and kicking. But not long after the car's reveal, it seemed to disappear. Now the basic idea has resurfaced with a few modern updates in a couple of US patents. The first patent is pretty straightforward and describes a range-extended EV similar to the BMW i3. At the front is an electric motor driving the front wheels. At the back is an internal combustion engine that powers an electric generator. In the middle is a lithium-ion battery for storing and delivering electricity. It's the same set-up as that Mazda2. The second patent is for an engine start-and-stop system, but specifically for rotary engines. The system is designed to shut off a rotary engine when not needed, much as modern piston engines do. It also stops the rotor in a position that closes the intake port to ensure no fuel or exhaust emissions slip out through the intake tract. This is necessary since there are no valves in a rotary, and air and exhaust come through ports that are "opened" and "closed" by the rotor itself. The patent also describes the possibility of firing a spark plug after the fuel has been cut to eliminate any leftover fuel emissions. This system would theoretically improve a rotary engine's fuel economy and emissions significantly, which would be a boon as those are two of the rotary's major weaknesses. The rotary-engine patent also includes the same range-extended powertrain drawing as the first patent. It's there as a description of a possible application. And in such an application, where the rotary wouldn't have to run all the time, the system could take advantage of the rotary's inherent strengths. Weight can be kept low thanks to the engine's small dimensions, which should help in keeping the car sprightly and efficient. Rotaries are renowned for smoothness, too, so it shouldn't need too much refining and sound deadening, the latter of which adds more weight. The small size would also help with packaging, leaving more space for people, cargo, or possibly batteries. And since it has been patented, the company may be looking to bring the system to market.

Will the Mazda2 be offered as a PHEV with a rotary engine range extender?

Every few months, it seems a rumor crops up about plans from Mazda to revive the rotary engine. Last November, its CEO said the only way another one could happen is if the project was profitable, and then a month later the automaker showed off the Mazda2 RE Range Extender with a 330cc Wankel engine mounted in the rear. Now, Australian auto site Motoring reports that the PHEV may actually make production in the next-gen Mazda2 sometime after it's initial launch.
Martin Benders, managing director of Mazda in Australia, spoke to Motoring about the company's future with hybrids and basically reiterated what the CEO said last year. The Japanese automaker only plans to offer electrified powertrains in places where they can sell in sufficient numbers to be profitable, like Japan.
Mazda has been playing with the rotary range-extender idea for years. In the RE prototype, the engine was exclusively used to charge the lithium-ion batteries when they were running low, and a 100-horsepower electric motor provided all of the propulsion. It gave the little hatch an estimated range of about 250 miles. The company reportedly took inspiration from its Skyactiv engines to make the Wankel have lower friction and a lighter weight.

Mazda3 successor due in dealers this fall

Following exciting new models like the 2013 CX-5 and 2014 Mazda6, Mazda is getting ready to introduce the next generation of its high-volume compact, the Mazda3. After talking to several of Mazda's dealers, Automotive News is reporting that the automaker is planning to introduce its new compact this fall, which is earlier than what was originally reported.
Aside from what we've seen in recent spy shots and what appeared to be a full-scale design mockup back in October, there is little information about the third-generation 3, but we can see that the car will get plenty of cues from Mazda's stylish Kodo design language, and we expect even more technologies from the company's SkyActiv efficiency program to come to bear. AN says that Mazda is hoping to top 300,000 sales this year in the US, and the sooner Mazda can replace the current aging 3, the better chances it has at reaching that goal.