Bye bye camshafts

[Maximumwarp]

On the one hand, this could be such an awesome technology. On the other hand, there is so much that could go wrong and be very expensive to fix.

http://www.roadandtrack.com/new-car...wild-freevalve-engine-runs-without-camshafts/

 

[p m]

On the one hand, this could be such an awesome technology. On the other hand, there is so much that could go wrong and be very expensive to fix.

http://www.roadandtrack.com/new-car...wild-freevalve-engine-runs-without-camshafts/

BMW experimented with magnetic valve drive - it could and would work, but would either require some good magnets or a lot of current to keep the valves open. It was simpler than Koenigsegg's design - and, design-dependent, the coils can be made easily field-swappable.

 

[Maximumwarp]

These are pneumatic. I didn't watch the video with sound, so maybe they said in there, but I wonder where the air supply is coming from. I suppose it wouldn't be terribly complicated to have a reservoir run by a separate pump somewhere. One of the goals appears to be freeing the crankshaft up from spinning other components, so I would guess its an electrically driven compressor.

 

[ERover82]

I wonder if more is gained by complete control over valve timing than reducing mechanical power loss.

 

[p m]

I wonder if more is gained by complete control over valve timing than reducing mechanical power loss.

Most definitely. You can have a silky-idling engine with flat torque curve almost up to redline.

 

[jymmiejamz]

I think Koenigsegg is the most interesting car company out there. I love all of the innovation.

From what I remember from a video about it a few years ago, they say it is 30% more power, 30% better fuel economy, and a 30% reduction in the size of the motor.

 

[discostew]

I wonder if more is gained by complete control over valve timing than reducing mechanical power loss.

Yes but reducing power loss is great too.

 

[discostew]

These are pneumatic. I didn't watch the video with sound, so maybe they said in there, but I wonder where the air supply is coming from. I suppose it wouldn't be terribly complicated to have a reservoir run by a separate pump somewhere. One of the goals appears to be freeing the crankshaft up from spinning other components, so I would guess its an electrically driven compressor.

I wonder if the advantage to being compressed air is the fact that at higher RPM the air would escape faster than oil. But it does seem like you already have oil under pressure so why pneumatic? I think that's cool as hell. I'm sure that kind of technology will be on a lot of stuff before to long. It makes perfect sense to me, eliminate moving parts is the name of the game. Lots of moving parts gone with that engine.

 

[Blue]

interesting....

 

[p m]

I wonder if the advantage to being compressed air is the fact that at higher RPM the air would escape faster than oil. But it does seem like you already have oil under pressure so why pneumatic? I think that's cool as hell. I'm sure that kind of technology will be on a lot of stuff before to long. It makes perfect sense to me, eliminate moving parts is the name of the game. Lots of moving parts gone with that engine.

My guess is that you don't want to tap regular lubrication circuit for valve control - I can imagine a lot of pressure fluctuations.
Wonder how they deal with the noise pneumatic actuators cause.

 

[Levi]

This was posted in a Saab forum a few years ago. It is a good video showing how it works and their test bed 9-5.

https://www.youtube.com/watch?v=Bch5B23_pu0&feature=share