Stripped F1 Gearbox

[autogyro]

Starting with 100% torque in one gear and then transferring to 100% torque in another, does the torque from the 'combined' gears (sum) remain 100% during the transition.

A difficult answer.....

Prior to the shift the torque being applied to the first gear is equal to engine torque (assuming clutch capacity is greater) times the ratio at the output. During contact the torque seen at the new gear increases from zero to the sum of the engine torque times the ratio of the new gear but in addition there is a positive torque spike seen as the result of synchronisation of the engine inertia.

In reality what you will see is an increase in output torque during the time of torque transfer but yes in its raw form 100% of the torque present on the input side will be continuously delivered during the transition.

No.
All you are describing is the same mechanical and hydraulic effects as have been present since the first layshaft constant and non constant mesh gearboxs in the 19th century.
The only difference is that in the early ones the gears are heavier and the oil thicker, so the 'inertia' of the disengageing gear continues to drive up to and beyond the disengage point, so you do not need the'zero shift' package.
If you undrtake a 'crash' shift with one of these old boxes you can match the gearshift speed of one of your all singing all dancing modern gearboxes with little trouble.
Sure it will jerk the vehicle and probably damage components but it 'works'.

[jenkF1]

I thought everyone runs dual-clutch boxes for the last few years?

As far as I'm aware dual-clutch transmissions are banned.

I do know there is an alternate system similar to dual clutch in principle but mechanically different

Can you describe the alternate system?

Hi cogs, sorry for the late reply. As mentioned dual clutches are not banned, but after reading the below scarbs explains that seamless shift F1 boxes don't have dual clutch but a different system to provide a 'seamless' shift with two selectors...

viewtopic.php?f=4&t=8914

The other system that it is similar to, im sorry I can only recall Evo magazine writing an article on a road car system with two selectors, mentioning the tech as similar to what we are seeing in F1. If I can I will fish it out!

[hardingfv32]

Regarding these current F1 gearboxes:

Do the engagement cogs on the slider and gear have a back rake to prevent a sliding out of gear phenomena?

Brian

[strad]

the phasing of one gear onto the next is aided by the usual throttle\ignition break

As I said.

[hardingfv32]

[quote="jenkF1" but after reading the below scarbs explains that seamless shift F1 boxes don't have dual clutch but a different system to provide a 'seamless' shift with two selectors...

Scarbs explanation is unsatisfactory. A 'throttle\ignition break' is not seamless. There is a period of less than 100% torque if you are using a 'throttle\ignition break'. A double clutch system can be seamless.

My reasoning: The cogs in the slider and gear teeth require a back-cut angle to keep the system from sliding out of gear. The back-cut angle causes an interlocking effect. If you do not use this back-cut angle then you have to hold the slider in position which would cause drag. Also, trying to break this interlock without reducing torque wears out the back-cut angles.

Brian

[strad]

As I understand it, A totally seamless shift tranny would be illegal.

[bhall]

You are correct, sir.

[hardingfv32]

As I understand it, A totally seamless shift tranny would be illegal.

All I can find is a prohibition on CVT transmissions. There is nothing else I believe. Can you quote a section?

Brian

[strad]

I'm off to work but there is a certain Ms requirement I think.

[bhall]

I just saw that much of the relevant section within the regulations is new this year, so it may very well no longer be an issue. I know there was provision in the past that had the effect of eliminating CVT, and I think it was a requirement for a specific, but very minimal, period of time between gearshifts where powered acceleration was prohibited.

[jenkF1]

I do recall in 2002/2003 Martin Brundle claiming that the Ferrari gearbox has two clutches.I would be interested in the specific article of the regs banning them.

I find gearboxes quite a complicated thing to get my dumb ass head around, and only really understand the basics and the basics of dual clutch and dog-cut gears. But I found some interesting info from the Redbull Haynes manual (which is awesome by the way )

"the selector mechanism itself is very similar in operation to that used in a motorcycle gearbox, with selector forks acting on each of the gears on the output shaft, to lock the appropriate gear to the shaft to engage the required gear.

All gears on the output shaft are in a constant mesh with the gears on the input shaft and any gear that is not engaged simply rotates freely on the shaft"

From what I am gathering from this, if this indeed the system in the 2010 redbull which the book depicts then its much more conventional than I imagined (with the next gear rotating freely/idling on the shaft rather than being spinning at the correct rpm as per dual clutch). So I am slighly confused on what changed when we heard hype about 'seamless shift' and for example, in 2009 I beleive when Force India finally develeoped seamless technology to catch up with everyone else.

[Richard]

So I am slighly confused on what changed when we heard hype about 'seamless shift' and for example, in 2009 I beleive when Force India finally develeoped seamless technology to catch up with everyone else.

I think the point is that the shift is not actually seamless, but the interruption in power during the transition of torque from one gear to the next is near negligible.

[autogyro]

So I am slighly confused on what changed when we heard hype about 'seamless shift' and for example, in 2009 I beleive when Force India finally develeoped seamless technology to catch up with everyone else.

I think the point is that the shift is not actually seamless, but the interruption in power during the transition of torque from one gear to the next is near negligible.

Correct Richard.
Also the gears not engaged do not just freewheel, they are driven round creating a large amount of oil windage.
All the hype about 'seemless' shifting is just that marketing hype.
All current stepped gearboxes have a 'reduction' in torque transfer during gearshifting.
Mechanical, hydraulic, pneumatic and electrical systems in use today that operate between the gears and shafts, do speed up the gear change they do not remove it|
For that you need my ESERU electric shift energy recovery unit.
If it were not for the current technicaly restrictive regulations all F1 cars would use it.

[jenkF1]

So I am slighly confused on what changed when we heard hype about 'seamless shift' and for example, in 2009 I beleive when Force India finally develeoped seamless technology to catch up with everyone else.

I think the point is that the shift is not actually seamless, but the interruption in power during the transition of torque from one gear to the next is near negligible.

whats the improvement over the old system though?

[strad]

Which old system?