Calling Engineers and milwrights...question!!

[Supafly]

Question is how do we wrap the steel cable on the drive drum without the cable winding left and right. We want the enter and leave points fixed.

Im stuck....can you guys help a brotha out?..


The only thing I can come up with is to enter from the left of drive drum, half wrap to a angled pulley and another half wrap back onto the right side of drum.

Is there a better method?...thanks!

[Nechako87]

draw it out

[sdubfid]

What diameter is the cable? What weight is being lifted? I can see an issue if it is stationary on the left and wrapped on the right side there would be a huge bend in the cable there.

Can you make an extended fairlead in the center? It would still wrap left and right but the entry and exit would be the same.

[Supafly]

The diameter of the stainless cable is 3/16".
Its for a shuttle running horizontal with 150lbs across (acel/decel) 25ft in 4 secs.
15.9 revolutions with a 6" drive drum.

I hope im not confusing you guys...haha but appreciate your help

[Nechako87]

is your drive drum grooved

[sdubfid]

Ohh, so this isn't a typical hoisting style winch being used for pulling only.

What if you just put a guide on the enter and leave points and let the middle take care of itself with the tension?

Is the cable riding directly on the drum surface?

[Supafly]

Originally Posted by Nechako87

is your drive drum grooved

Yes the entry and exits are grooved.

Originally Posted by sdubfid

Ohh, so this isn't a typical hoisting style winch being used for pulling only.

What if you just put a guide on the enter and leave points and let the middle take care of itself with the tension?

Is the cable riding directly on the drum surface?

Yes the cable will be riding directly on the drum surface. There cannot be any slippage between the cable and the drum due to the drum having a rotary encoder hooked up to a computer to monitor the distance of the travelling shuttle. The shuttle is attached to the moving cable.

The shuttle is 10ft long. There are two cables moving the shuttle. If one of those cables was to slip, the shuttle would bind. We would also not know the true position of the shuttle; which is critical. There are a total of 30 shuttles.

We would like to use chain, but due to the volume it would cost huge huge bux.hahaha

Whooo...my head is gonna explode. If we get a solution, i'll spot you guys at the bar.

[Nechako87]

if your drive drum is grooved then how can the wire go across the drum like that? wouldn't you wire be riding ontop of the grooves?

[Supafly]

Originally Posted by Nechako87

if your drive drum is grooved then how can the wire go across the drum like that? wouldn't you wire be riding ontop of the grooves?

To get enough friction, there is multiple wraps. This causes the spool left and right. How do you get enough friction so the cable does not slip on the drum? and the distance travel becomes an exact quantity.....

[sdubfid]

I'm trying to picture this in my head.

So you have a shuttle in the middle and a winch on either side that move the shuttle from side to side? There will be 1 cable per side and 1 encoder per side?

So 2 winches, 2 cables and 2 encoders? Are the winchs powered by servos?

[Supafly]

Originally Posted by sdubfid

I'm trying to picture this in my head.

So you have a shuttle in the middle and a winch on either side that move the shuttle from side to side? There will be 1 cable per side and 1 encoder per side?

So 2 winches, 2 cables and 2 encoders? Are the winchs powered by servos?

There is one 10ft long shaft with 2 winch drums on it. 2 cables and 1 encoder.
The winches are driven by gearbox and vfd. (variable frequency drives)

[sdubfid]

Does the whole system look like this?