Please have a look at:
http://jalopnik.com/the-future-of-the-i ... -369015485
This is fascinating R&D from Koenigsegg: engines without a camshaft. Does anyone know more about it? I am struggling to find detailed technical descriptions of how this works.
Camless engines
- Mr Cholmondeley-Warner
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Re: Camless engines
Crankshaft sensor and some electronics that fire the actuators for the valves, I assume. Infinitely variable valve timing.
Nick
- StressedDave
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Re: Camless engines
Quite some time ago, I worked with Lotus Engineering and they had camless engines on the go. They were using hydraulic actuation with a coupe of Moog servovalves (5k each 21 years ago) operating each valve. Gave the engineers the abiity to test any camshaft profile...
I can't belive that pneumatic valve actuation is the future, certainly compared with variable valve lift and timing cam technology. Just the pressures needed for decent actuation speed and the ability to overlap valves is huge nd you then have the issue with sudden air pressure loss. Even F1 when it had pneumatic valves only used them for clogin rather than opening.
It sounds way more blue sky than it does production ready.
I can't belive that pneumatic valve actuation is the future, certainly compared with variable valve lift and timing cam technology. Just the pressures needed for decent actuation speed and the ability to overlap valves is huge nd you then have the issue with sudden air pressure loss. Even F1 when it had pneumatic valves only used them for clogin rather than opening.
It sounds way more blue sky than it does production ready.
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Re: Camless engines
I remember reading, donkeys years ago, about Renault experimenting with solenoid controlled valves, such that, as others have said, timing could be very variable.
Might the problem be reliability? The traditional system has its faults, related to poor design or parts specification and user ignorance but, mainly, works, for most of the time.
However, all controlled by an ECU, to ensure no "interference"?
Might the problem be reliability? The traditional system has its faults, related to poor design or parts specification and user ignorance but, mainly, works, for most of the time.
However, all controlled by an ECU, to ensure no "interference"?
- ChristianAB
- Posts: 270
- Joined: Mon Sep 28, 2015 9:51 pm
Re: Camless engines
StressedDave wrote:It sounds way more blue sky than it does production ready.
That's the part that has me thinking: Koenigsegg seems to have a car, with a camless engine, and which is doing miles after miles seemingly without issues. Considering that in the past, they have tended to deliver on the technology side, then, what is it that they are doing that the rest of us don't know? Looking at the video, they are big on the use of compressed air, but you still need something else to actuate it. Given the frequencies involved, it seems that they are able to do it in a way that is new.
I just can't figure out what that could be (Plus I am still going through the maths of vibration isolation and inerters from another thread, so can't allocate much time to this).
Frustrating, grrrrr
- ChristianAB
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Re: Camless engines
Ok, so it seems that there is a spring which pushes back the valves when the pressure from the compressed is not applied. So then, what is left is working out how they are able to apply on/off pressure so quickly with that compressed air.
- StressedDave
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Re: Camless engines
As it's an all or nothing thing, that's very easy - very high pressure and standard valves - remember you can trigger the valves early if you know their response time.
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