need help on overrunning clutch!

[IronPony]

Can someone give me a lesson on how the pto overrunning clutches work? I want to hook up two pto's two one main shaft and want to protect either tractor if either one would stop?

Thanks

ironpony

 

[Billpa]

could you shed more light on the subject ,more info is needed.

 

[NEsota]

With an over riding clutch on your PTO output shaft, the input shaft to the implement will be engaged (locked to the PTO) unless the second shaft is trying to turn faster than the PTO shaft. If the second shaft is turning faster than the PTO then the dogs in the clutch are disconnected. If the implement is, like a bush hog and has a flywheel effect, then you need the clutch but if it is one like a sickle mower that has little flywheel effect, then you do not need it. The clutch is a safety device, if it is needed do not leave home without it.

 

[John N Mi]

I also am interested in this subject as the three point rotary tiller that I just bought has one. My booklet says that the clutch can slip if the tiller is jammed. What is not clear is wether the clutch goes next to the tractor or next to the tiller. I think next to the tiller. Is this right?
John

 

[Oldmax]

A overide clutch & a slip clutch are two different "dogs" . An overide clutch keeps an attachment from powering the tractor, such as a brush hog "Used on 8N & tractors without Live power" . Being that the PTO is hooked to trans gears directly with no clutch between PTO & wheels .

A slip clutch is just that , Will slip before damaging something else .

 

[Oldmax]

Sorry I didn't give you answer you wanted just the difference . The overide clutch is built like the starter clutch on a B/S small engine with a pull starter . But has rollers in the place of balls . will let tractor drive implement but not let implement drive tractor.
Just like when you pull starter on small engine
you can start with pull but engine will not turn starter .

 

[Jeff-oh]

oldmax hit it square. I do not think the OCR is the right thing you are thinking of.

If two OCR'd PTOs fed into one drive shaft then only one PTO would be doing the work, the other (slower running PTO) would be over-run and thus not providing any power...

You will never be able to get the both turning at the same speed.

 

[Mike M]

Sounds more like you want a slip clutch on each shaft.

 

[Janicholson]

With respect,I disagree, though at an idle, your construct is good, if the tractor PTOs were within a few RPM of each other this difference would disappear the moment a load was placed on the shaft. Both clutches would be driving and both engines powering with proportional throttle opening according to their governors. It might not be perfectly ballanced, but it would drive well from both. JimN

 

[IronPony]

hi this is for my saw mill. my power unit lacks enough horsepower to saw the bigger logs. the power unit is hooked to the main shaft by roller chain and i can back one of my tractors up to the end of the shaft and hook up to provide the needed horsepower and that's were I was going to put the orc. the powerunit would do most the work and the tractor pick up the slack . hope this helps.

 

[badpenny]

Maybe removing some teeth from the blade would help, fewer teeth = less power to turn

 

[KIP in MX]

Whatever you want to call it, it needs to be a sprag type clutch. We have two engines feeding one main driveshaft thru a combining gearbox to the transmissions on some of our helicopters and each engine has it´s own sprag inside the c-box. If either engine shuts down, the clutch allows the engine shaft to stop, while other engine still powers the main driveshaft.
Now if either of your engines would be overloaded by running the PTO by it´s self, you have another problem to overcome. Isn´t an over running PTO clutch basically the same thing as a sprag?

 

[Janicholson]

YES JimN