Shaft Rotation Only Driven By Motor

'Only driven by motor' is in my opinion a huge mistake, use a gearbox, it adds very little cost, simple gearboxes with a worm and wheel or just 2 cogs will vastly improve the performance and control.

I'd experiment with dc motor gearboxes, things like door window motors from cars.
For commercial quantities look at companies like Crouzet, Rotalink etc and for huge quantities look to the far east.
Or google for local companies, like I did in this project... (3rd line down gives the name of my motor gearbox supplier)

Del

Is it include a friction ring to prevent sliding / rotation due to unbalanced loading?

As Del said, use a gearbox. You stated that you only need to move slowly - with say a 100:1 gearbox, you'd be able to use a motor with about 100^th of the torque you'd need for direct drive.

If you're not fussy about the speed, you'll probably get away with fwd-off-reverse control (but you may need a brake to maintain position with the motor off^[1]). If speed is important use a servo motor with an encoder (or resolver) for feedback (a much more expensive approach). You may need a brake anyway to stay safe if/when the power fails^[1]. For constant-ish loads, you could probably use a speed controller which uses the motor back EMF for speed control.

Thing to do is write it all down. How fast do you need to go? What is the worst-case load (both total mass and unbalanced load)? What torque do you need to apply to the wheel shaft to cope with that load? How deep are your pockets?

Always remember there's more than one way to skin a catsquirrel .

[1] You won't need a brake if you use a worm drive, as they're (almost) impossible to backdrive.

I found a DC motor which could revise rotation direction for revising the poles, it seems very suitable to this design.

As it need to revise direction very frequently in operation, what kind of switch shall I need?

Is the worm gear also fulfil rotation in both directions and fast reacted?

Ken,

Is this a follow on for the reciprocating machine?

Tell us what your goal is, we'll get heads together and sort it out.

Yes, the full simplified picture is like this

Solenoid system acting as a "drop hammer" to speed up the squeezing process.

As liquid level may be varied, motor is to control the solenoid position.

Is this design principle OK?

Thanks

What provides the down force?
I don't se how a counter-balance system can act as a drop hammer.
Or is the solenoid pulling down somehow?
It doesn't really make sense.
Del

When the solenoid cut off, the slug will drop automatically.

Oh, I think I get it, the solenoid pulls up the slug and then drops it and sort of hammers it through the die.
Does that mean the extruded output material gets pulled back and forth through the die?
Del

One uncertainty is that when the drop hammer (slug) system in contact with viscous fuild, extra friction induced for pulling back.

I thinks it will be similar as a pump principle.

Most time the slug is in a position in contact with fluid.

In reality you need a positive displacement pump connected to the bottom of the tank. The pumps first non-return valve will ensure the fluid is drawn in from the tank, but not forced out again. The second non-return valve allows the fluid to be forced out in to the delivery line but not to be drawn back in again. A DC solenoid coil with spring return could power the pump, but not the AC one you have. The DC solenoid would have to be pretty hefty.

Sorry to have pee'd again.

I think you may be right, but until we get to know what this "highly viscous fluid" is, we're wasting our time.
An auger (your meat grinder) with a dead weight on the feed hopper would work find to my way of thinking.
PS I've knocked 1 off your "off topic" score. It's the best idea so far!

After seeing this why not use a cylinder to put a force on it. If it needs to be pulsed can easy be done.

" ... why not use a cylinder ... " - do you mean pneumatic/hydraulic?

Either would need a lot more than just a motor/gearbox. It would be OK if there was an air supply (or a handy hydraulic pump) already available.

Actually the tank is a strip like rectangular box with row openings. I will put a metal strip inserted into the tank and driven by the solenoid slug.

"- do you mean pneumatic/hydraulic?"

40 pounds is all he has it counter balanced for. So pneumatic. The cost of the motor and gear box will be more then a small compressor to do the job. Most dispensing equipment of viscous fluids I've seen is done with metering gear pumps or pneumatic pumps. Rate of flow of the pneumatic pump depending on the pressure applied.

Air pump or submersible pump are you taking?

Is it applicable in a strip like rectangular tank section?

(I want the pressure to be even everywhere)

The pumps are not submersible. They use a platen that seals to the wall of the container. Pressure from cylinder or cylinders force the medium into the pump. Systems I have here are for hot melt adhesives and sealants.

Whats the viscosity of the medium your trying to dispense? If the medium is not too viscous just the cylinders may do.

Use a cylinder with a platen that will seal to the walls as it goes down. The cylinder can proved a constant force. Which by regulating the pressure on it will change the volume of flow.

'Ees a maka da spagetti.
Del

It would be too expensive to make such pump+fitting

I don't use the pulley system.

Upright electric screw jack + supporting wire + solenoid

The worm drive is bi-directional, and will react as quickly as the motor (it has relatively low inertia).

As for the choice of switch, I suggest you follow Tony's advice - give us the full story, and we'll give you a hand to find the best solution.

You should really do the sums to calculate what torque and speed characteristics you need (or if you know this data for your motor, to calculate the gear ratio and pulley diameter etc.).

You may have a brake drum attached to the motor and an Electromagnetic brake (most of the crain motors are of that type) the EM brake releases when the motor is energised and closes back when the power is cut off.

The gear box is a better concept than VFD or stepper motor where the control system may be more complicated than the equipment.

UD15

Where did EM brakes, VFD or stepper motors enter in to this?

Not sure but it got him a GA

First an escalator is moving stairs. You mean elevator? Most elevators do not use a counter weight. A draw works is used or on short lift hydraulic cylinders. The line is anchored to a fixed point and run through tackle.

How about mounting the solenoid assembly to a satellite dish actuator? Then it won't bounce all around the way it would on this rope-and-pulley system.

Would this arrangement be better than pulley arrangement?

You may have a variable speed motor as drive...

I'm not 100% sure, but I do think that the linear actuator would be better.

As the slug pull up causing a upward shock load, I thinks slacking of string is a good method to relieve such load than rod.

Please select 50 kg Chain Electric Hoist with slow hoisting /lowering speed. It will be cheaper and simple solution. No counter wt. etc. reqd.

Is it easy to find a hoist with a capacity as little as 50Kg (Actually the max design total load / unbalanced load is 25Kg)

Any website?

HI youngken, Are you from U.S? If yes then type Electric Chain Hoist in Google, you will get many in the list. Reputed makes are C&M, Demag, Kone,Morris, etc.You may contact local distributor by searching in yellow pages.

In India you may get at the half the price but servicing, shipping etc. may be problem.

What on earth are you trying to force through the orifice, sounds like cold porridge?

To get a better push from the drop weight, reduce the diameter and increase the height of the storage vessel to give a smaller surface area to push on.
Just another thought turn the solenoid the other way up and use the weight of the yoke and coil as the drop weight. Believe me that solenoid will pick up it's own weight.

I want to see photo's of this in action when its finished!

I'm getting a little bell ringing in the back of my head going back to my days at school.
Would this have anything to do with pottery?