Freelander 1 HCU - Hippo Coupling Unit (TM)

Freelaner said:

through the viscous fluid and the greater surface area of the vcu unit.

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I'm thinking it would be the same size.
You still need vanes for the hardening fluid to cling to.

If not, um - you could get out and blow it every couple of miles?

I dunno - I'm sure there's a way

Freelaner said:

An EMF would generate a great deal of heat.

how would you dissapate it?

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Given the 2 options I'd rather keep me hellfire missiles and stick with ma vcu.

bukko said:

I'm thinking it would be the same size.
You still need vanes for the hardening fluid to cling to.

If not, um - you could get out and blow it every couple of miles?

I dunno - I'm sure there's a way

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the only way i've found is to get my standard unit re-conditioned with the latest in fluid technology. they wouldn't tell me what they used but it was "new and improved"

my vcu gave up after 80k and took my entire drivetrain with it

it is certainly worth a try, but I have a sneaky suspicion it will not handle the torque.

Hippo said:

Given the 2 options I'd rather keep me hellfire missiles and stick with ma vcu.

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me too

plus, given the nature of electricity and magnetism, it could inadvertantly trigger an implosion of space time too

bukko said:

Sorry to bump, but this thread is far too interesting to let die.

Just a thought I had (so probably bad) but what if the two halves of the HCU contained overlapping coils, so that rotation at different speeds turns them into their own electromagnet? The fluid contained at the centre of the unit would be surrounded by the EMF, so should be in the ideal position for the effect to occur.

Would obviously need loads of PITO testing but you could vary the number of coils until you got to the ideal solution.

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Interesting idea. The magnetism would have to be massive to get anywhere near 1 to 1 ratio to have permanent 4x4.

Electromagnetic clutch - Wikipedia, the free encyclopedia

it appears electro-electro clutches are vary rare except for low torque requirements - the usual scenario is electro-mechanical - see link

Yup I just read up more on MR fluid.

The disadvantages are low shear strength, thickening over time and high cost.
Even if it works, it may not be any different to a conventional VCU anyway!

don't get me wrong it's a nice idea and i'm quite sure one that Land Rover engineers will have looked into, but cost effectiveness, effectiveness and practicality rule.

Well I'm still looking at a clutch type idea, using 2 ABS sensors (which as we all know never go wrong! )

All interesting stuff, good reading and a great idea. It all seems to be getting complicated tho. I think the vcu is actually a good idea but we are having problems simply because we arent changing them in time. Constant workload by the vcu because of pick n mix tyres and such like must surely limit the life of them. The vcu is a simple and effective system, its just a shame it doesnt last forever without needing replacement. Theres definetly advantages in keeping things simple. If I had to choose anything other a vcu it would be a lockable centre diff. New vcu beinv fitted tomorrow, looking forward to it

WLJayne said:

I VOLUNTEER!

Seriously Hippo that's a fooking stonking idea. I'd be well up for seeing if we can make that work, maybe talk to Bell about getting different fluid in there. But it can't be hard to rig up a eletcro magnetic coil, maybe mounted to the VCU damper. GENIUS!!

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BEWARE your posts have a way of biting you on the bum

Well, it might be ultimately pointless, but so is mountain climbing.
And this is a bit safer.

Instead of trying to redesign the VCU, why not look into changing the diff or IRD gearing to match so we have 50:50 drive all the time instead of fake FWD bias? Surely this will stop the VCU eating itself anyway??? Or am I missing something?

Spacemonkey... said:

Instead of trying to redesign the VCU, why not look into changing the diff or IRD gearing to match so we have 50:50 drive all the time instead of fake FWD bias? Surely this will stop the VCU eating itself anyway??? Or am I missing something?

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Would the vcu itself take the strain on 50/50? Not sure.

Spacemonkey... said:

Instead of trying to redesign the VCU, why not look into changing the diff or IRD gearing to match so we have 50:50 drive all the time instead of fake FWD bias? Surely this will stop the VCU eating itself anyway??? Or am I missing something?

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You are missing something

The FWD priority protects the IRD.
If it were 50:50 drive, IRD wind-up would be worse!
The best thing would be to have a completely disconnected rear drive, until the front sped fast enough to need assistance from the rear.

I think...

bukko said:

You are missing something

The FWD priority protects the IRD.
If it were 50:50 drive, IRD wind-up would be worse!
The best thing would be to have a completely disconnected rear drive, until the front sped fast enough to need assistance from the rear.

I think...

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how do you work that out , its not 50 /50 but equal speed ,with the differential in driven speeds as are ie slightly different v/c has to slip all the time somewhat equal sped of drive would mean v/c worked less as with rrc and p38

bukko said:

You are missing something

The FWD priority protects the IRD.
If it were 50:50 drive, IRD wind-up would be worse!
The best thing would be to have a completely disconnected rear drive, until the front sped fast enough to need assistance from the rear.

I think...

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or better differentials perhaps, that actually protect the drivetrain form things like mismatching tyres, irregular tyre wear etc.......

Spacemonkey... said:

Instead of trying to redesign the VCU, why not look into changing the diff or IRD gearing to match so we have 50:50 drive all the time instead of fake FWD bias? Surely this will stop the VCU eating itself anyway??? Or am I missing something?

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Did you mean keeping or losing the vcu? Surely having the vcu protects you from wind up regardless of gear ratios. My previous post regarding strain on the vcu was thinking along the lines of you asking more of the rear wheels ( too much too soon) once the front wheels start to spin, instead of just a helping hand. On 50/50 , with a vcu it would probably need to be a much bulkier vcu? Or is it just getting late?:boom:

musky81 said:

Did you mean keeping or losing the vcu? Surely having the vcu protects you from wind up regardless of gear ratios. My previous post regarding strain on the vcu was thinking along the lines of you asking more of the rear wheels ( too much too soon) once the front wheels start to spin, instead of just a helping hand. On 50/50 , with a vcu it would probably need to be a much bulkier vcu? Or is it just getting late?:boom:

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getting late