Question on overrunning clutch coupler use on a rotary tiller

[North Idaho Wolfman]

For example, an operator depresses or feathers the clutch while making a slow turn with a cutter, so that's the "disengaging of the PTO" stated above. The cutter continues to spin at a certain rpm, and now the operator completes the turn and lets the clutch out so that's the "engaging" of the PTO. But the output rotational speed of the PTO (slower) doesn't match the rotational speed of the input shaft to the cutter gearbox (faster), so without an ORC, a ratcheting kind for example, the cutter would deliver a shock to the PTO output shaft, due to the mismatch in rotational velocity.

Sorry again but no.

Let make sure we are talking apple to apples and kiwi to kiwis.

Clarity: Overrunning clutch and a one way clutch are the same thing.

Yes, Your clutch pack reduces shock loads via it's design.

The one way clutches job is not to reduce or eliminate shock loads.
In fact most one way clutch failure is from shock loads.
It's job is to not allow a spinning PTO driven mass to push the transmissions and thus the drive wheels.

In the scenario you present:

Without a one way clutch:
Pushing in the clutch to make a turn, would leave you still traveling at whatever speed you pushed the clutch in at, the tractor would be pushed around the turn without slowing until the mower slowed down (been there done that not fun).
And No the brakes would do you know good, it would be like they are non existent.
It's like having cruise locked on!

With a one way clutch:
The tractor can slow with the mower still spinning at whatever speed it was at when the clutch was disengaged and yet not push the drive portion of the transmission.
thus allowing you to slow the tractor turn then reengage the clutch.
Now this is critical to the shock load, if the engine is still at the 540 (output) rpm and you reengage the clutch and connect to the now 500ish pto speed you SLAM the one way clutch causing a huge shock load.
In order to not have that shock happen you would have to make sure you have slowed the engine to lower rpm then the implement then very slowly raise the RPM till the one way clutch reengaged.
Not an easy or simple task to accomplish.

Clear as mud?

 

[North Idaho Wolfman]

All of this has come about because a member keeps going on and on about his ORC on his Land Pride cutter and yet he lists his tractor as an M7060. So why the heck is he lauding the ORC when his tractor doesn't need it?

Yes you are 100% right a M7060 has no need for an overrunning clutch.

 

[mcmxi]

Sorry again but no.

Let make sure we are talking apple to apples and kiwi to kiwis.

Clarity: Overrunning clutch and a one way clutch are the same thing.

Yes, Your clutch pack reduces shock loads via it's design.

The one way clutches job is not to reduce or eliminate shock loads.
In fact most one way clutch failure is from shock loads.
It's job is to not allow a spinning PTO driven mass to push the transmissions and thus the drive wheels.

In the scenario you present:

Without a one way clutch:
Pushing in the clutch to make a turn, would leave you still traveling at whatever speed you pushed the clutch in at, the tractor would be pushed around the turn without slowing until the mower slowed down (been there done that not fun).
And No the brakes would do you know good, it would be like they are non existent.
It's like having cruise locked on!

With a one way clutch:
The tractor can slow with the mower still spinning at whatever speed it was at when the clutch was disengaged and yet not push the drive portion of the transmission.
thus allowing you to slow the tractor turn then reengage the clutch.
Now this is critical to the shock load, if the engine is still at the 540 (output) rpm and you reengage the clutch and connect to the now 500ish pto speed you SLAM the one way clutch causing a huge shock load.
In order to not have that shock happen you would have to make sure you have slowed the engine to lower rpm then the implement then very slowly raise the RPM till the one way clutch reengaged.
Not an easy or simple task to accomplish.

Clear as mud?

Yep, clear as mud. An overrun clutch allows the tractor to transmit a torque to the implement, but prevents the implement from transmitting a torque to the tractor. If that's not right then I quit!

 

[Tx Jim]

An ORC will not protect tractor or tiller from damage due to obstructions and is not needed with a tiller.

Nothing wrong with shear pin protection if proper shear pin is used.

ORC was designed to allow a high speed implement such as rotary mower to not back feed through tractor pto/trans causing tractor forward speed to continue when clutch pedal is depressed on tractor with transmission driven pto. IMHO when pto is turn off after operation tiller tines will stop rotating in touching the soil eliminating any benefits of an ORC if installed.

 

[North Idaho Wolfman]

Yep, clear as mud. An overrun clutch allows the tractor to transmit a torque to the implement, but prevents the implement from transmitting a torque to the tractor. If that's not right then I quit!

BINGO!
We'll call that a win!

 

[Russell King]

And I have learned how the PTO gets power on newer tractors!

Thanks for the information and diagrams

 

[johndeerebones]

Shear Bolts are cheap and they work, slip clutches MUST be slipped and adjusted. A seized slip clutch won't slip. Crescent wrenches and extra bolts live in my toolbox on the tractor as my brush cutter uses them. If they're cared for, slip clutches are fine. Shear bolts are simple. Add-on over running clutches make me think 8ns, old Power-masters, etc.