cam drive efficiency
cam drive efficiency
(OP)
which type of camshaft drive offers the least parasitic loss; belt, chain, or gear?
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RE: cam drive efficiency
RE: cam drive efficiency
So, I'm inclined to bet on on the belt until more info arrives.
But I think the losses in the drive are pretty small compared to the power required to drag cam lobes across surfaces while overcoming hundreds of pounds of spring pressure and inertia.
RE: cam drive efficiency
You mean friction power at the cam-follower interfaces?
RE: cam drive efficiency
Kyle
RE: cam drive efficiency
straight cut gears 99% per pair
chain 98-99% at low speed, much less at high speed
timing belt 90%
The timing belt was being used as the final drive in a solar car, so it may have been running under too high a torque.
Cheers
Greg Locock
RE: cam drive efficiency
Camless Engines
A near future where camshafts don't exist and
performance is revolutionised!
By Dusko Mackoski
http://www.autospeed.co.nz/cms/A_0910/P_2/article....
...
The valvetrain in a typical internal combustion engine comprises several moving components. Some are rotating and
some are moving in a linear manner. Included Included are poppet valves that are operated by rocker arms or
tappets, with valve springs used to return the valves to their seats. In such a system the parasitic power losses are
major - power is wasted in accelerating and decelerating the components of the valvetrain. Friction of the camshaft,
springs, cam belts, etc also robs us of precious power and worsens fuel economy, not to mention contributing to wear
and tear. The power draw on the crankshaft to operate the conventional valve train is 5 to 10 percent of total power output.
...
Now when I try to check the weblink, they want me to pay to read it.
I guess that's not clear and precise - exactly why I didn't post this earlier. I was expecting a clearcut and knowledgable reply with debate about fine intricacies of it all. Posting it now doesn't seem so bad.