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3-Dimentional-Cam Design: "Tomorrow’s Engine"
Targets Global Environmental Concerns
Advanced Suzuki Motorcycle Technology
Shows Promise for Optimal Use of Resources |
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Suzuki believes that the 3-dimentional-cam engine could be "tomorrow’s engine", a promising technology to make optimal use of non-renewable global resources, while reducing CO2 emissions in the near future. The 3D-cam engine is designed to obtain about 20% enhancement of fuel efficiency and up to 6% more torque output throughout the rev range (by Suzuki in-house measurements) with minimal modification to existing engines. Since the only changes required are above the valves, less expensive conventional engine production technology can be used. Altogether, the 3D-cam engine offers an exceptional combination of advantages : lightweight, compact construction with high-revving design and lower production costs than most engines intended to improve environmental performance.
The engine uses innovative cams to continuously vary engine characteristics – from that of the Miller cycle (with high fuel efficiency at low loading) to the Otto cycle (producing powerful output under high loading) – while delivering both optimum fuel efficiency and power-output characteristics throughout the rev band. Because the throttle valve can be
eliminated, pumping losses can also be greatly reduced.
The cams are shaped with a continuous, 3-dimentional set of properties – valve lift, acting angle and timing – optimized for a variety of running conditions. Spherical roller tappets act on the cams and electronically controlled axle actuators slide the cams along the axles to vary power output continuously from idling to maximum output.
In the low-output, low-rpm range required for most travel on public roads, the valve lift and acting angle are kept small and valve-closing timing quick for a Miller-cycle operation (compression stroke shorter than expansion stroke) offering better fuel efficiency. In the high-output, high-rpm range, the valve lift and acting angle are both larger than those for
similar-sized conventional engines, substantially increasing the power. And since the 3-dimentional-cam also varies the timing in addition to the valve lift and acting angle, there is no
need for a variable-valve-timing mechanism.
In sum, it’s possible that Suzuki technological innovation has created "Tomorrow’s Engine". |
