Disengaged Flywheel and shaft under normal operation

[Francis]

We would like to know if there is any clutch mechanism available wherein the clutch is in the disengaged position under normal operation, that is the flywheel is not connected to the output shaft in normal operation. The engagement of the flywheel and the shaft must be done only when a lever is applied. Any mechanism is welcome and it is preferable that the system is completely mechanical.
Thank you in advance.

[Francis]

We would like to know if there is any clutch mechanism available wherein the clutch is in the disengaged position under normal operation, that is the flywheel is not connected to the output shaft in normal operation. The engagement of the flywheel and the shaft must be done only when a lever is applied. Any mechanism is welcome and it is preferable that the system is completely mechanical.
Thank you in advance.

[Jan_Dressler]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Francis:
We would like to know if there is any clutch mechanism available wherein the clutch is in the disengaged position under normal operation, that is the flywheel is not connected to the output shaft in normal operation. </div></BLOCKQUOTE>
Yes.


Maybe it would be quite interesting to know:
- For what engine (or generally what purpose)?
- What speed?
- Torque?
- Why?

[Francis]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">HS Karlsruhe </div></BLOCKQUOTE>
This is for a KERS unit which transfers a torque of 7.8N-m from a flywheel to the wheels. The power is 847W. The clutch needs to engage the flywheel and the wheels only at time of charging and discharging the KERS unit.

[AxelRipper]

Sounds like you should be able to come up with some sort of electrically servo actuated clutch setup. You're probably not going to find what you need off the shelf. It may be possible to get some sort of generic drive clutch off of something and control it electrically as to when to lock up for charging, with a button for discharge.

Just an idea, but thats why us engineers get paid the mediocre bucks!

[Drew Price]

I agree with AxelRipper - trying to get an all-mechanical system to work like that would probably end up being much more time consuming and more complex than a simple analog electrically controlled system, though you'd need an actuator capable of actuating the clutch control.

~850W is not much power, is this for like an RC car or small go-kart or something?

[Adambomb]

Indeed...if you don't mind us asking, what is this for? It sounds interesting, but obviously not legal for FSAE, not big enough for something bigger than FSAE, and too complicated for most cars smaller than FSAE that come to mind. http://fsae.com/groupee_common/emoticons/icon_wink.gif

[kcapitano]

I dont think you need to go the electronic route. Just purchase a standard clutch and put a big spring under the actuating mechanism (so it's like you're always pulling the clutch in). Then just push, or pull, on the lever to engage the clutch when you want it.
But if you do want to go the electronic route might I suggest an electro-pneumatic system?

[AxelRipper]

As I'm thinking about this, it may be possible to charge this using some sort of weighted system to get it to a target speed (see governors on older gas and steam engines)and then have a lever which can engage it.

Or possibly using a CVT to spin it up (look at GoPeds or other small transport devices for small CVT's) so it would only put power into the flywheel rather than vice versa, and then just have a pressure plate on another plate that when actuated would rub on the flywheel to transfer the power back to the axle.

There I go really thinking something out... But then again, it is an interesting proposal.

[Francis]

Thank you guys for some really good ideas.

This is for a Mechanical Kinetic Energy Recovery System(KERS) unit which recovers energy during braking for a motorcycle of about 120kgs. Its a project we are working on.

[Mumpitz]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">ic Energy Recovery System(KERS) unit which recovers energy du </div></BLOCKQUOTE>

Ball ramp clutch, shat tons of clamping force with little input force.