Clutch mounting?

[mx_tifoso]

Of the current teams which ones have engine or gearbox mounted clutches?

I figure this is one of the areas in which cars can actually [greatly?] differ nowadays so it's kind of interesting.

I've googled for this but no luck, does anyone have current images showing the setups?

[riff_raff]

There was some justification at one time for gearbox mounted clutches, since a clutch failure would not necessitate an engine change. Don't know if this is still true though.

Here's an installation drawing from AP for their 4-1/2 inch carbon clutch:

http://www.apracing.com/drawings/cp8153cd.pdf

riff_raff

[mx_tifoso]

There was some justification at one time for gearbox mounted clutches, since a clutch failure would not necessitate an engine change. Don't know if this is still true though.

...

Probably even more so now with the penalties and the 8 engine limit. And changing a gearbox is a more rational choice; lesser penalties and easier/quicker to do.

[747heavy]

What has a clutch failure and change to do with the engine/gearbox change penality?
You don´t need to change the engine/gearbox if you have a clutch problem.

You just need to split the engine from the gearbox to change the clutch, so it does not really matter where do you mount it - in this respect.

AFAIK there is no penality for changing the clutch - yet.

IMO - the AP drawing does not show a current F1 clutch.
Current F1 clutches are smaller in diameter, and are pull type clutches, rather then push type as shown in the drawing.

Not sure what is the latest trend this year, but it was common to mount the clutch to the crankshaft/engine.

[747heavy]

@mx_tifosi

If you have a look in the latest RCE magazine, the story about the Cosworth engine, so see the clutch mounted to the engine.

[autogyro]

Who needs a clutch?

[flynfrog]

Who needs a clutch?

the same idiots that think you need a gearbox

Gears are 19th century tech welcome to the electric age.

hub motors with variable timing and reconfigurable coil arrangement is where its at.

[Edis]

To mount the clutch on the gearbox offers a few advantages. The shaft play on the gearbox input shaft is typically less than that of the crankshaft, which allow better release control of the clutch. The environment close to the gearbox also tends to be a bit better than on the engine.

Electrical transmissions have been around for a long time and they have some big drawbacks as a 70-80% efficiency compared to 85-95% for the gearbox, and a significant weight handicap.

The electric motor is by the way also 19th century technology, of course, only a moron would care about such silly claims. If a technology works well it doesn't matter when it was invented or introduced.

[autogyro]

Eh what is this 'electric transmission' you mention Edis?
What has this got to do with the need for a clutch in F1?
Dry plate clutching an ic engine to a gearbox input shaft is very very crude.
Often the wheels spin up uncontrolably or the engine stalls.
Hardly modern efficiency is it.
The cone clutch on the 1908 Panhard et Levasser I am helping to rebuild is more efficient for the purpose. Very little slip or chances of engine stall amd over 100 years old. Twin cam engine as well.

[747heavy]

not from this year, but shows clutch location

[DaveKillens]

One important consideration is to pass as little torque as possible through the clutch. The more torque you have to deal with, the larger and beefier the clutch has to be.

And the torque is at it's lowest value coming off the crankshaft, before it goes through gearing that multiplies torque.

[autogyro]

One important consideration is to pass as little torque as possible through the clutch. The more torque you have to deal with, the larger and beefier the clutch has to be.

And the torque is at it's lowest value coming off the crankshaft, before it goes through gearing that multiplies torque.

The only reason for the clutch on an F1 car is to establish vehicle inertia,

[riff_raff]

Dave Killens,

F1 friction clutches are basically shaft speed synchronization devices. This means that their function is to transmit power between two shafts (the crank and trans input) turning at different speeds by slipping, until the two shaft speeds are equalized. At that point it simply becomes a fixed coupling.

The excess power produced during the slippage is rejected as heat. This power term is simply the transmitted torque times the relative speed difference divided by a power constant. Friction clutches are designed by thermal capacity, and not so much by an ability to transmit torque. If torque transmission was the only concern, then a single clutch plate could be made to work by increasing the clamping force. The reason multiple plates are used is to provide enough thermal mass to prevent the temperature rise in the plates during slippage from exceeding safe levels for the CRC plate materials. The reason small diameter plates are used is to minimize the polar inertia of the clutch pack and to keep the engine CL as low as rules permit.

The AP drawing I linked is for a 115mm (4.5 inch) dia clutch, which is quite small. I believe current rules require an engine crank CL at least 58mm above the reference plane (ie. the underwing OML). So a 115mm dia (57.5mm radius) clutch pack would seem appropriate.

Also, the current rules allow a clutch change regardless of whether it's engine or crank mounted. As long as the shaft it's mounted on is turning at crank speeds.

Regards,
riff_raff

[mx_tifoso]

I don't know how you do it but you're explanations are great Riff_raff. Although one may sometimes have a basic grasp of how a car works in general, posts like the one above certainly help to get a clearer picture, at least in my case. And in conjunction with the rest of the posts I understand this much much better. Thanks to all.


Please continue though...

[Edis]

Eh what is this 'electric transmission' you mention Edis?
What has this got to do with the need for a clutch in F1?
Dry plate clutching an ic engine to a gearbox input shaft is very very crude.
Often the wheels spin up uncontrolably or the engine stalls.
Hardly modern efficiency is it.
The cone clutch on the 1908 Panhard et Levasser I am helping to rebuild is more efficient for the purpose. Very little slip or chances of engine stall amd over 100 years old. Twin cam engine as well.

Electric tranmissions are found in some ships (with pod propellers for instance), diesel electric locomotives and similar applications. Simply a transmission that consist of a engine mounted generator and a traction motor.

A friction clutch is 100% efficient once it is fully engaged where it spends most of the time, which is not the case with most other options. To control the engagement of the clutch isn't that difficult either, if you put it under electro-hydraulic control with a few sensors you can have perfect engagement every time without have to suffer from a powerloss when the clutch is engaged.

Of course, a cone clutch is just a type of friction clutch.

Dave Killens,

F1 friction clutches are basically shaft speed synchronization devices. This means that their function is to transmit power between two shafts (the crank and trans input) turning at different speeds by slipping, until the two shaft speeds are equalized. At that point it simply becomes a fixed coupling.

The excess power produced during the slippage is rejected as heat. This power term is simply the transmitted torque times the relative speed difference divided by a power constant. Friction clutches are designed by thermal capacity, and not so much by an ability to transmit torque. If torque transmission was the only concern, then a single clutch plate could be made to work by increasing the clamping force. The reason multiple plates are used is to provide enough thermal mass to prevent the temperature rise in the plates during slippage from exceeding safe levels for the CRC plate materials. The reason small diameter plates are used is to minimize the polar inertia of the clutch pack and to keep the engine CL as low as rules permit.

The AP drawing I linked is for a 115mm (4.5 inch) dia clutch, which is quite small. I believe current rules require an engine crank CL at least 58mm above the reference plane (ie. the underwing OML). So a 115mm dia (57.5mm radius) clutch pack would seem appropriate.

Also, the current rules allow a clutch change regardless of whether it's engine or crank mounted. As long as the shaft it's mounted on is turning at crank speeds.

Regards,
riff_raff

A clutch have to be designed both for the torque it has to transmit and the heat it absorb during slippage. For any torque capacity, a multiplate clutch will offer a lower inertia compared to a single plate clutch of the same capacity. This does of course also apply to the thermal mass.