hydraulics engineering question
 

I'm doing a story on this antique cane loader and I have a question. There is a "thing" that looks like a hydraulic cylinder about a foot long and 4" in diameter that has hoses going to it but the ram is connected to nothing. The ram moves in and out as the boom on the loader swings side to side. Why is this "thing" in the hydraulic system? What function does it perform? What is it called?

http://forums.pelicanparts.com/uploa...1332941345.jpg

The loader


http://forums.pelicanparts.com/uploa...1332941484.jpg

The "thing"

It's a double acting cylinder. Push/pull type. Hard to say what is controlling from this picture, but with what you say in the description, it is controlling the side to side movement.

Can't be controlling anything not hooked up to anything but I bet it was.

Hillybilly position indicator

Might be an accumulator

That was my exact thought.

Maybe its a damper. A acumulator would be connected in series..... cylinders are parallel devices. How is it connected.

Cushioning of "boom" swing at end of strokes is likely purpose - connections would provide a clue.

I would agree. What else could it be?

But if it was supposed to cushion the swing it would have four hoses instead of two. I'd like to see where those hoses go.

Looks like it's just their to isolate one part of a circuit from another and this is the pressure transfer point. There is probably a piston connected to that shaft you see at the bottom. With the piston there, it could also limit movement. So one side is connected to the pump and the other side is connected to the ram that operates one of the linkages. Pump could lose pressure or blow out, but the ram would stop when the piston tops out.

The owner mentioned something about it being "maybe a damper or something" so that could be. How would it work? Anyone got a schematic of a hydraulic circuit with such a damper in it?
Thank you for all the replies. The brain trust here is amazing.

Cushioning device or in layman terms a damper

If you could show the routing of the hoses that would probably do it.

Leaving town for a few days but when I get back I'll look over the photos I have and see if they give a clue. Thanks.

Dampening can be provided in the valving by using a motor spool instead of a cylinder spool. If that is a dampener with the piston extension out of the bottom? Could it be that that use to be part of a "cylinder action" that is no no longer part of the tractor?

Actually talking to my farmer buddies this is probably the best explanation. Some additional component or function that was deemed nonessential by a previous owner.

Some thought and research has provided this possible explanation:

It is used to actuate simultaneously, with matching flow to both cylinders, with one valve, two cylinders that are plumbed in series. The rod end of the first cylinder pushes out less fluid during the stroke. This volume of this fluid is effectively multiplied by routing it into the fixed dummy cylinder rod end. The non-rod end of the dummy cylinder feeds the second cylinder of the two in series. To reverse direction the rod end of the second cylinder is provided with the hydraulic pressure.