Forward/Reverse with a Single Belt

I hope this clears things up....

Thanks for the info,but I cannot see how the belting is routed.

I have considered:

A one-way ball bearing setup,and two pulleys.

A set of pulleys,one driven from the outside of the belt,one driven from the inside of the belt,on a double-sided v-belt. ($)

An electric clutch.($$)

An electric clutch/brake.($$$)

Even a drive from the camshaft of the motor,which turns backwards from the engine,although at half speed.(Camshaft is direct gear driven on motor,no chain).

I am still looking for the simplest,cheapest method.

Of course,there is always the Fred Flintstone Drive,but my feet are not tough enough for that on gravel road.

It seems a simple idler gear setup would work...the one belt will take some fancy gearing I think....

https://en.wikipedia.org/wiki/Idler-wheel

http://www.wheatfarm.com/actractor/

The Continental or Rio engines had a camshaft PTO. Also high nickel chrome block.

The Lawn boy Loafer had a disc on the engine shaft and linkage to move the disc from one side of a rubber tired wheel to the other for forward/reverse and into and away from center for speed control.

This is just a guess. Maybe you had more than one driven pulley and clutches to engage one or the other, with one having an extra gear to reverse rotation.

I do not see how the direction of single belt rotation can change unless there is a gear and/or multiple shaft transmission between the engine and the tines.

With only one drive belt from the engine to the tine assembly I would think the direction of operation is limited to following engine rotation direction.

I have had several tillers over the years and all of the reversible units have had a simple two-way transmission (gear or belt) on them between the engine and tine assembly.

I am very interested to see how a change of direction can be accomplished using only one drive belt.

Maybe the engine mount rotated to twist the belt? No, wait.....never mind.

A Troy Built transmission!

It looks to me as though the direction would stay the same when the belt moves to the other side of the pulley. In the diagram the top of the belt is moving, say, left to right. When you move the idler, the belt contacts the other side of the pulley but the bottom part of the belt is moving right to left. The rotation of the driven pulley is unchanged.

You are correct.

Thanks for pointing out my error.

I have to go back and think about this a little more.

The pulley would have to switch between the inside of the belt to the outside of the belt to get reverse direction.

In your diagram, if the belt ran back over the top of the driven pulley instead of underneath, you could use 2 pulleys to lift one side of the belt or the other off of the driven. Or, you could do the same but have 2 driven pulleys on the same shaft with clutches to determine which one drove the shaft.

Nope. This will not change the direction as the belt engages the same pulley traveling in the same direction.

I have to assume you are talking about the connection between the wheel (sailboat type) and the actual tiller. How did you switch from one direction to the other?

The large amount of cast iron should have been a clue that he is talking about a rototiller (for tilling earth), not a boat tiller.

There is not one type of "connection between the boats wheel" and they are not just for sailboats, and the rudder. On sailboats the most common methods are: cable and chain; hydraulic; rack and pinion connected thru a shielded flex cable; and sometimes, but not many recently, a length of nylon or Dacron rope.

To reverse the cable and chain cross the cable before attaching it to the rudder post. For the hydraulic position the cylinder from the other side of the rudder post. For rack and pinion simply mount the rudder rack on the other side of the pinion on the rudder shaft. For the rope, put a cross in it. Or do as I prefer, get rid of the wheel and go back to what the Norse did---> put a tiller on the boat!

No belts on the steering rigging of a boat!

Good Luck, Old Salt

How about a steam locomotive drive mechanism as a model, which can turn the wheels in either direction, depending on the start point....

If I could figure out how to draw a picture to this site, I could show you how to make it work with one belt, one drive pulley, one moveable idler pulley, and a pair of output pulleys geared, chained, or belted together.

The movable idler pulley would allow the belt to run against either the output pulley inside the belt loop, or against the output pulley outside the belt loop. But because the two output pulleys are geared or chained to run as a pair, the direction of the output pulleys would change direction depending on weather the output pulleys were driven by the belt directly, or by the other output pulley and the gear or chain. Only one of the output pulleys would have to be connected to do work.

Can you grasp my thoughts on this?

Simply draw your sketch in paint or some other graphic program, and save the file as a jpg in your picture file, then click on the green camera icon and select the file...

Thanks. I'll give it a try.

oops

Simple. Two input pulleys straddled the upper portion of the drive belt, and the output of the pulleys ran to a planetary gear whose center/sun gear was the drive shaft. The planetary gear arrangement was rigidly mounted, and by shifting the position of the idler pulley up or down only one of the input pulleys would contact the drive belt. Basically which surface of the belt (inner/outer) that is contacted determines the direction of motion.

Let's assume that the motor is on the right and the top of the belt runs from right to left (CCW) to the idler at the left. If the top/outer side of the belt contacts the upper output pulley then it moves the top planetary gear CW which in turn moves the sun/output gear CCW. If the bottom/inner side of the belt contacts the lower output pulley then the lower planetary gear rotates CCW which in turn moves the sun/output gear CW. There's even a neutral position where neither output pulley contacts the belt.

I'll leave it to the mechanical engineers to figure out the best way to move the belt up and down; it could be by moving the leftmost idler pulley up/down, moving the caged output pulleys and planetary gear combination up/down, or using opposing idler pulleys to push the drive belt up/down.

GA! Yes you have identified the basic Troy-Bilt and other tiller drive systems however this clearly illustrates the required gear assembly in addition to the single drive belt.

troy built does this by moving the engine up and down. When up the belt is under tension, when down the pulley is run by direct connection to the outside of the pulley.

Hello I consulted google with the same question as you, because I wanted reverse in a antique inboard 5hp boat motor with belt drive. I also had a tiller with said reverse system many years ago but couldnt remember how it worked. After reading and searching i found this...