Camshaftless Engine - Koenigsegg

[tok-tokkie]

Here is a video of an engine that has no camshaft. Valves are opened pneumatically & closed by air spring. Revs up to 20 000 rpm.
Sulzer have been doing camless exhaust valves on huge marine engines but this is suitable for small high speed IC engines & more compact than a conventional OHC engine.

http://www.youtube.com/watch?v=Bch5B23_pu0

[autogyro]

Mr Koenigsegg is obviously a dedicated engineer of the highest calibre.

Many people have looked at this idea, we did back in the 80s.
It was a logical direction to take from our work with automatic gearbox development and the control hydraulics.
There were a number of potential problems.
In earlier decades of course the computer control systems were not available for reliable operation.
Simple electric switching was insufficient.
Over all reliability was not sufficient for a production application as most failures resulted in catastrophic engine damage.
The need for an air compressor and/or oil pressure system added complexity volume and weight.
At that time the systems under test were no smaller than the cam system itself.
Starting the engine using stored air pressure and or stored oil pressure was unreliable.
We tested using a sprung resevoir in the engine oil circuit.
It proved very difficult to control valve seat contact sufficiently to reduce seat and valve wear to an acceptable minimum.
This also resulted in a very noisy valve to seat contact, which coupled to the air hammer noise was considered unacceptable.

The video on work in progress at Koenigsegg looks promising however and I would love to test that Saab fitted with the system.

[Richard]

Presumably there is a compressor to get the pneumatic system charged on start up, then the engine fires.

Bear in mind Koenigsegg is a low volume production company so they can adopt a craft approach to making these devices. I can imagine scaling up for mass production will be a different matter.

[autogyro]

Presumably there is a compressor to get the pneumatic system charged on start up, then the engine fires.

Bear in mind Koenigsegg is a low volume production company so they can adopt a craft approach to making these devices. I can imagine scaling up for mass production will be a different matter.

I like the approach taken by the company to involve everyone in development.
Reminds me of the old days.
Today most car companies and even F1 employ people with highly focused disciplines.
Like a degree in basket weaving to make the seat covers.
You dont get innovation from that.

[ninno_]

Question is how people will take aproach to it and define it as usable thing in future car industry. I think it will define combustion engines in some way and in what we will see....

[autogyro]

I am not sure the future will be hydropneumatic valve operation.
With the inevitability of hybrid and EVs, I see a huge area of development in electromagnetics.
I was impressed with the transmission set up work undertaken by the Koenigsegg test driver on each car.
It was a shame the work was being undertaken on an old fashioned layshaft stepped ratio gearbox.
Much like the newly released Ferrari this will result in a complex and energy wasting powertrain if Koenigsegg develop the inevitable hybrid models based on it.
Good performance figures with the extra electric power available for acceleration but impossible future emission regulations to overcome if a large IC engine is retained.
Unlike Ferrari Koenigsegg do not have Fiat production to fiddle the emission figures for them.
Unless that is they can get a camless valve system working and a far better powertrain.
What better future hypercar hybrid than one that uses an intigrated powertrain using electromagnetics for operation and control, including valve actuation and transmission operation.
With hybrid batteries, there would be the electrical storage on board to achieve this in a much more compact and lighter package than current hybrid hypercars.
I think Koenigsegg is capable of achieving such a concept where as the bigger companies do not have the inventiveness available from their top heavy production set ups.

[countersteer]

Simple electric switching was insufficient.
...

It proved very difficult to control valve seat contact sufficiently to reduce seat and valve wear to an acceptable minimum.
This also resulted in a very noisy valve to seat contact, which coupled to the air hammer noise was considered unacceptable.

Is the issue how to bring the valve to a stop... smoothly... at peak lift and, more importantly, when it seats?

Back in my school days, I put some thought into the concept and couldn't figure how you were to control the valve if a pneumatic or hydraulic circuit was providing a constant force. F=MA The valve continues to accelerate throughout its travel and is at peak speed when it seats or reaches peak lift. Bang..

Any idea how Koenigsegg managed it?

[autogyro]

Is the issue how to bring the valve to a stop... smoothly... at peak lift and, more importantly, when it seats?

Back in my school days, I put some thought into the concept and couldn't figure how you were to control the valve if a pneumatic or hydraulic circuit was providing a constant force. F=MA The valve continues to accelerate throughout its travel and is at peak speed when it seats or reaches peak lift. Bang..

Any idea how Koenigsegg managed it.

I dont know if Koenigsegg have fully achieved it.
They give 60,000 miles for their Saab test vehicle but I have never seen or heard it running.

A conventional cam and valve has carefuly designed valve acceleration in one simple curve that is dictated by the cam lobe profile.
Designing a 'free' valve operating system produces a complex range of valve accelerations in its projected operational envelope.
It is then difficult to ensure good valve sealing and acceptable impact forces during valve closing.
At the time of my involvment, I came to the conclusion that I would rather follow a different valving system for four stroke and two stroke engines.
I looked at 'sleeve' valve aero engines from late and post WW2 that used this type of valving.
I was hoping to achieve a variable sleeve valve design that would reproduce the breathing variations of a 'free' poppet valve design like the Koenigsegg.
With todays electronics controlling the sleeves and perhaps operating them electromagneticaly, I am certain this could be achieved.
Again I think a small compact company like Koenigsegg could build such an engine, where as large companies would avoid the production costs and headaches.
When I looked at this idea, the electronics were not available to develop it and I was diverted into a study of potential changes in the basic mechanical layout of IC engines.
Interesting directions are possible from a number of engines.
The Deltic and the Commer two stroke civil engines and the RR Crecy, Napier Sabre and Bristol sleeve valve aero engines.
Take a look.
However my main field is transmission development so I have not followed the engine side as far as I have with electromagnetic transmission systems.

[autogyro]

I believe the take up of hybrid technology for hypercars will open the gates so to speak on the development of electronic and electromagnetic developments in vehicle motive power.
The need to carry electrical storage for hybrid use will allow the use of electromagnetic energy for systems like poppet valve actuation and transmission operation.
It will be a huge area of development in which I would like a much better involvement.
The hydro pneumatic valve system that Koenigsegg are looking into will help with the development of production capable electromagnetic system in a hybrid car.

[woohoo]

Alfa Romeo uses camshaft less intake valves in the MultiAir engines now.
The exhaust valves are still mechanical camshafts however.

[Holm86]

Alfa Romeo uses camshaft less intake valves in the MultiAir engines now.
The exhaust valves are still mechanical camshafts however.

They are not camshaftless no. They are still connected mechanically to the camshaft. There are just som hydraulics allowing them to change the lift seamlessly.

[Chengine]

Their valve actuator technology is exactly what I need for air-injection valve in Chen engine.
The Chen engine uses high pressure compressed air to purge out residual waste gas near TDC. I have been looking for such a fast actuator to drive the valve. Now I have found it. Does any one know if I can purchase one from Koenigsegg?

I have a discussion tread on this forum, "Chen Engine, a more efficient and cleaner engine"

Regards,

Chengine