It's Friday: videos of variable transmission, cylinder deactivation, power grid
There are many green, automotive concepts - like variable transmission, cylinder deactivation and plugging into the power grid - that you might have heard about but have never seen. Want to see those concepts in action and not in a computer animation? Above is a video showing how a variable transmission system works. Think of the simple mechanics you can find on a ten-speed bike. Below the fold are two more videos including one of how power grid lines, so important they cannot be taken down, must be repaired by helicopter. Also below the fold is video of what actually happens in a cylinder, that tube with the piston and spark plug. Enjoy!
[Source: YouTube, Google Video]
Reader Comments (Page 1 of 1)
daeil 7:17PM (11/16/2007)
Wow... i was amazed by the powergrid guy...
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Joseph 12:39PM (11/17/2007)
Really good videos.
The CVT shown on top though, looks really flimsy. I hope they work better than they look! Really neat video of what goes on in a cylinder and of the powerline/bird guy.
But..why did you talk about cylinder deactivation if none of the videos were about it.
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Lascelles Linton 8:34PM (11/16/2007)
Joseph, I really just wanted to show everyone cool videos (it's Friday) but keep a theme of green transport concepts because this is AutoblogGreen after all :D I could have gotten into cylinder deactivation more.
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Chris M 10:52PM (11/16/2007)
The CVT shown is just one of many types of CVT, and that particular type is not used for cars. There is a different "cone and belt" system used for some vehicles, using 2 pairs of cones as a set of pullys for a V belt made of steel links.
The CVT used by Toyota, Ford and Nissan hybrids uses a single planetary gearset and two motor/generators, the variation is achieved by varying the speeds and torques and direction of motor/generator one.
The GM/Allison "dual mode" hybrid system also uses two motor generators, and two planetary gearsets along with several clutches. It acts as a variable speed transmission at slower speeds, and like a standard 4 speed transmission at higher speeds.
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rgseidl 8:17AM (11/18/2007)
A more modern version of the dual-cone CVT uses a steel ring and traction oil instead of runners and a belt. The oil actually solidifies momentarily under the high pressures at the contact point - the metal parts do not touch! The system is simple and quite efficient but with only one contact point per cone, maximum torque is quite limited. It should therefore only be considered for small vehicles.
The link below is to a very nice 140MB computer animation of the KRG from Germany transmission specialist GIF. However, the design has been implemented and used successfully in European Formula Student racing.
http://www.ecurie-aix.rwth-aachen.de/downloads/krganimation.mpg
Instead of cones, you can also use toroids (donut shapes) to achieve variable transmission ratios. The transmitting elements are usually multiple disks or spheres. With more contact points, these designs can transmit greater torque in a given package using similar traction oils. One initial application is bicycles, another the upcoming KERS hybrid system for F1. The hard (i.e. expensive) part is getting each transmitting element to actually handle something close to its intended share of the load.
http://www.youtube.com/watch?v=Smijjy832X0&feature=related
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