Mechanical Question - Gears

yes! and the other way too

I might add...

Or, no worm at all, and just and the bottom of the hole.

I was going there if you did not.

If the frictional forces are very low and the worm gear very lightly loaded, then I would say yes. Otherwise no.

I would say the opposite, nearly. The frictional force needed to drive a worm (gear) using a non-toothed wheel should be quite high indeed, such as dry metal with dry rubber. I would not count on your temporary solution to your problem to hold up very long at all. If the output torque required is high, you will most likely cut the rubber wheel on the worm before you turn it.

?

O The wheel to drive your worm.

Here is a set of spares too; ? O Heavy duty types.

1- Who mentioned a NON TOOTHED gear ?

2- Even in this case the helix angle is the MOST important factor. A non toothed gear transmits power via friction and thus friction should lead to a torque > resistant torque.

3- The gear turns around an axis NORMAL to the worm axis. If the helix has a too low ratio pitch/diameter the tangential component (with respect to the worm axis) is small and the wheel will wear without turning the worm.

4- In previous discussions friction was understood as flank sliding friction between helix and wheel teeth. This seams not to be very well understood by some participants.

The OP directly stated can a wheel drive a worm. Nothing in that statement implies the wheel is toothed or is a gear. In fact, nothing is stated about the nature or relative angle of the wheel to the worm. If the wheel is a solid brass rim (for example), attempting to drive a worm with the two axes of rotational perpendicular, I would have to say that it is very unlikely to produce rotational motion on the worm (output) shaft unless wheel to worm pressure is enormous, no lubrication is present, and there is virtually no or extremely low load on the output.

Mainly there will be a lot of heat generated, considerable noise, and maybe if the worm is a harder material than the wheel, the wheel will cut its own teeth on the worm and begin to drive it at some point in the progress of wearing out.

Please don't shout.

Yes, if the ratio is low enough. (Around 20:1 or less, iirc, but it depends on lubrication.) For this reason, worm gears are not considered as braking devices on lifting applications.

Don't know of any....not a very efficient set-up...

I think you're right. How couldn't it?

NO. THE WORM DRIVES THE WHEEL.

It depends on the helix angle. If it is small i.e the ratio pitch/diameter low it functions as an irreversible drive friction is in right range.

If the ratio pitch/diameter is high and the angle accordingly and friction is low then it can work as a reversible drive although with a bad efficiency.

As example the gears with not parallel shafts, it is the same kind of drive.

Last time I had a worm drive (Radicon) run back it was quite spectacular.

First time I've ever seen a part of a gearbox inside the motor, the rotor was sat on the floor behind the stator.

The OP seems to have left. We don't yet know whether the possibility of back-driving a worm gear is desirable or undesirable to his/her situation.

Yep, think about a water wheel and an old mill press.

Yeah, Massey, especially if there are worms in the water! The water wheel was, I think the prime mover, whereas the final output was a 90 degree drive using a toothed wheel, and something resembling a worm gear.

Yes it can.

It all depends on the co-efficient of friction for the material being used and the lead angle on the worm.

The most common place to see this in action is in the differential of some vehicles. Stutz, Peugeot 404, Audi are some of them. The advantages is they are quiet, strong and, depending on if the worm is at the bottom or top of the wheel you can have additional ground clearance as in the Hummer or if it is at the bottom of the wheel you can have a flatter floor pan and therefore more room in the vehicle. The down side is they are expensive compared to a crown and pinion bevel gear.

The wheel has to be able to drive the worm every time you go down a hill or you would have a lock up situation.

BAB

It is totally possible to drive a worm gear with a wheel, provided the wheel in question has geared teeth to drive the worm gear. However, a plain wheel will provide little or no traction to the worm drive and any loading on the worm gear will create slippage and reduced drive on the worm gear driven component.

However, if you have the wheel with teeth mating to the worm gear, then Yes, the wheel will drive the worm gear, not efficiently, and the worm should have very little loading. i.e. a bicycle wheel speedometer, (Older types were driven by a geared plastic/nylon wheel, to a plastic/nylon worm gear that drove a flexible drive shaft attached to a needle).

Perhaps defining your question and adding details would obtain a good and correct answer to your impending predicament.

I give you a GA for that, also add that I agree this would not be an efficient drive mechanism (unless perhaps it were the other way around with the worm driving the gear).

It appears the OP left the building after his dog ate the worm.

No.

Worm can drive wheel but surely wheel cannot drive worm.