F1technical.net

Thanks Scarbs, nice pic!

Do you know wich car is it? Does it has an horizontal 3rd shock/spring? Are the pedals missing there?

Interesting. Looks almost as if you could convert that to pull suspension.

scarbs wrote:

cool man!

Interesting, first time i'm getting this kind of shot.

ringo wrote:
cool man!

Interesting, first time i'm getting this kind of shot.

You should check gurneyflap

not many cars with low mounted steering rack around in F1...

Brawn 2009,Renault 2010,Mclaren 2010...

RacingManiac wrote:Trying my best here with the pics...

Thank you!

I was putting too much emphasis on the link between the left and right sides, totally missing what happens when the third spring pivot can move to allow single wheel bump.

I had always assumed that the vertical post had to be the ARB - but trying the work it through from the pics, I convinced myself it couldn't work.

Now I can see.

Thanks again.

So the helper spring on the third spring is quite likely to be there to allow a little movement of the pivot post in single wheel bump before the third spring engages.

Belatti wrote:Thanks Scarbs, nice pic!

Do you know wich car is it? Does it has an horizontal 3rd shock/spring? Are the pedals missing there?

I googled the picture, which was quicker than going through my archive of photos. Its a 2002 Renault and pretty typical of a front ARB installation, aside from Ferrari and the Brunner designed Minardis, that use a ingenious blade type ARB. Its lacking a heave damper, you can see the links on the rockers where it would fit.

At the rear most teams run a simple "U" shaped ARB, i.e. two levers on a torsion bar, the "T" type you see on the Renault only suits the old format of vertical torsion bars and lay flat dampers. As most teams now run ~horizontal torsion bars, with the ARB seperate from the heave damper. Interestignly soem teams have created an intermeidate linkage between the rockers and the ARB, I assume to alter the effective roll rate or add rising rate, McLarens one is pretty typical of this type and is also found on the FI.

speedsense wrote:The top one, closest to the t-bar, appears to be a helper spring. Helper springs keep the sprung unit from rattling loose during extension, and are quite light in spring rate by comparison. This is likely a dual sprung unit, not a triple. IMHO

Perhaps. However, it would be a surprise if there isn't a bump rubber in the stack.

The issue (for me) is that the rate change(s) will happen suddenly (apart from the bump rubber). Sudden changes in rate wouldn't inspire driver confidence if they happened during a manoeuvre. No doubt, and with no road inputs, that could be avoided by careful "tuning", as RH suggested. In reality, however? Unlikely, I think.

Why not marry a single spring with a long(er) bump rubber, "tuned" with packers? Removes any requirement for a "helper", would probably reduce weight and would make rate changes smoothly progressive....

I dont think that would work to keep the ride height acceptable with the DF changes with speed Dave.
As usual aero rules OK.

autogyro wrote:I dont think that would work to keep the ride height acceptable with the DF changes with speed Dave.
As usual aero rules OK.

Mmm. I think you have it, auto. "Aerostatics" rules OK. Does work for LMP, GP2 & (some) F1 teams, however.

DaveW wrote:

speedsense wrote:The top one, closest to the t-bar, appears to be a helper spring. Helper springs keep the sprung unit from rattling loose during extension, and are quite light in spring rate by comparison. This is likely a dual sprung unit, not a triple. IMHO

Perhaps. However, it would be a surprise if there isn't a bump rubber in the stack.

The issue (for me) is that the rate change(s) will happen suddenly (apart from the bump rubber). Sudden changes in rate wouldn't inspire driver confidence if they happened during a manoeuvre. No doubt, and with no road inputs, that could be avoided by careful "tuning", as RH suggested. In reality, however? Unlikely, I think.

Why not marry a single spring with a long(er) bump rubber, "tuned" with packers? Removes any requirement for a "helper", would probably reduce weight and would make rate changes smoothly progressive....

why not throw away the steel spring altogether and just have a bump rubber with zero gap but a very low initial rate and progression ? got 800g of weight removed from the car instantly..

That would suit the aero guys if the cars drove on glass but one bump and they would go airbourne.

marcush. wrote:why not throw away the steel spring altogether and just have a bump rubber with zero gap but a very low initial rate and progression ? got 800g of weight removed from the car instantly..

Curiously, I've seen that solution. It's a question of load capacity, I guess, & the proportion of the load carried by the corner springs. For example, it probably wouldn't work with no corner springs (I've seen that solution, too).

marcush. wrote: why not throw away the steel spring altogether and just have a bump rubber with zero gap but a very low initial rate and progression ? got 800g of weight removed from the car instantly..

Something like that has been used previously - a stack of, effectively, dished washers used as a very stiff bump stop that also worked as a third spring. Not as ultimately compliant as a coil spring though.

I guess the issue is that the cars have a very large weight change in the course of a race compared to the refuelling days.