Can anyone ID this engine component?
 

It's part of a common governor system fitted to many planes that have the
prop pitch set by a system using oil pressure to move a piston in the prop
hub.

What is that large disk for?
It looks like it is attached to the manual speed control shaft.
http://www.b3tards.com/u/57a418c694b...roppitch22.jpg

Looks to me like it's simply a wheel to adjust the governor with, notice how there is a pin on the bottom to lock it in place (and the corresponding holes in the wheel).

After actually reading the article I realize the above statement is entirely wrong and I shall now STFU

But it's attached to the mechanism the pilot uses to change the prop pitch.
Why would you want to lock that in place?

Would it be a maintenance thing or would it be locked in flight?

Check out this site:

http://www.enginehistory.org/Propell...ors/hydgov.htm

Depending on the mechanism, you probably have to lock it in place?

yes, that is where my image is from, but it doesn't explain the purpose of the large disk.

Possibly the "pin" is actually a spring loaded ball detent, which would act like a friction to hold the selected position

Ahhh! Now that makes sense.
That would suggest that planes with this system would, in effect, have a
limited number of prop pitch settings (as many as holes on the disk).

If it's a governor for a constant speed unit you don't directly set the prop pitch through any setting. What your actually setting is the RPM. The CSU sets the prop pitch to what ever it needs to maintain the RPM at a given throttle setting if it can (any where between coarse and fine).

It's hard to see but if you look at the cut away diagram on the link, the disk is attached to the "speed control shaft" (No 1 on the diagram, but then again my eyes are dim and weak with old age)

(quote)
That would suggest that planes with this system would, in effect, have a
limited number of prop pitch settings (as many as holes on the disk).



It appear's that the setting was in increment value of five (5)

The holes are more likely to be for attaching and adjusting the linkage, the fact that there's so many of them is to adjust movement set by the throttle.

The position of this set the props rpm limit and the governor controls the overspeed/underspeed condition of the propeller.

The holes are not related to the pitch angles


"The propeller governor maintains a constant engine speed by controlling propeller pitch. Engine speed is selected by a cockpit control connected to the governor speed control shaft."


EDit

Shoshi Tiger had explained it well enough.

It's not likely that the holes are for a linkage point because of the interference of the so called "pin' area (its clearly butted against the disk), there would be no clearence for the linkage mechanical attachment if the disk is designed to rotate 360 degrees. We are all just guessing here, but I think a ball detent is the most likely explanation.:)

definitely not

this is what I mean by the holes are used for installing linkages

http://www.vincesrocket.com/2003-06-30/prop5.JPG

[quote=KG26_Alpha;123649]definitely not

this is what I mean by the holes are used for installing linkages




If you follow the shaft that's attached to the disk, you will notice a cut gear on that shaft...that tells me that the disk is designed to rotate 360:)

[QUOTE=SlipBall;123652]no it cant turn 360

the shaft only moves up and down about a 1/4 turn to apply tension to the spring.

Anyway thats irrelevant to the point of the disks purpose which is to attach cable components for rpm position.

[quote=KG26_Alpha;123655]


OK then, thank's

would it be a Flyweight, by any chance?


it spins and creates the forces necessary to determine underspeed or overspeed.... like a flywheel operated torsion wrench. (instead of levering the torsion wrench on a bolt head for example, to the specified torque as in your car's engine head bolts, the torsion levering is performed by RPM... kinetic energy, with the holes used to balance the wheel itself)

at least that's what the cut away engineering drawing (plus blurb) from the earlier link, looks to be ?

No

you sure?


http://www.enginehistory.org/Propell...HydPropGov.jpg






also... http://www.thaitechnics.com/propelle...control_2.html


http://www.thaitechnics.com/propelle...rspeed_gov.jpg


don'tcha just hate naming conventions, o lack of?

Yes