BX25 FEL Valve Curl Detent
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BXpanded
Silver Member, Approved Advertiser
When you move the control lever to the right to dump the loader bucket, the valve allows the fluid in the rod end of the cylinder to flow to the non-rod end as it is extending instead of returning it to the tank. At the same time, the flow from the hyd pump is directed into that same end. This does 2 things: It prevents or minimizes cavitation for lack of a better term, in the non-rod end that is filling. It also allows the bucket to dump very quickly. This is referred to as a regeneration circuit.
If you push the control lever farther to the right you will find resistance or detent. When you push the lever past that detent, it cuts off the transfer of fluid from one side of the cylinder to the other side. It then behaves as a normal hydraulic circuit with fluid from the pump going to the filling end while the fluid from the rod end returns to the tank. The result is slower movement of the cylinder but more power.
Note: Regen circuits only work when extending a cylinder rod. The cylinder movement is the result of equal pressure on both sides of the cylinder's piston, but the force is created by the unequal piston area because of the cylinder rod. (more area on the non-rod end)
Clear as mud now???
The regen has no real similarity to the float function where both ends of the lift cylinders are essentially open to the tank.
If you push the control lever farther to the right you will find resistance or detent. When you push the lever past that detent, it cuts off the transfer of fluid from one side of the cylinder to the other side. It then behaves as a normal hydraulic circuit with fluid from the pump going to the filling end while the fluid from the rod end returns to the tank. The result is slower movement of the cylinder but more power.
Note: Regen circuits only work when extending a cylinder rod. The cylinder movement is the result of equal pressure on both sides of the cylinder's piston, but the force is created by the unequal piston area because of the cylinder rod. (more area on the non-rod end)
Clear as mud now???
The regen has no real similarity to the float function where both ends of the lift cylinders are essentially open to the tank.
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Clear as mud and THANK YOU.
But here is why the questions. I need to juice up an additional cylinder for a grapple for the FEL bucket. I wanted to use a Simple Valve Multipling valve from Fasse but I am hearing that valve interferes w/ this regen circuit and I "think" I see why. I assume the Valve Multiplier does not allow the fluid to flow in regen mode.
Blast, I really didn't want to run a ton of hoses ot do this...
I am no better off on what to do. Darn I wish I had know this from jump street. I will find a way, it just won't be so elegent and simple.
But here is why the questions. I need to juice up an additional cylinder for a grapple for the FEL bucket. I wanted to use a Simple Valve Multipling valve from Fasse but I am hearing that valve interferes w/ this regen circuit and I "think" I see why. I assume the Valve Multiplier does not allow the fluid to flow in regen mode.
Blast, I really didn't want to run a ton of hoses ot do this...
I am no better off on what to do. Darn I wish I had know this from jump street. I will find a way, it just won't be so elegent and simple.
CHDinCT
Veteran Member
Hmm, not sure why the regen function would work for the dump/curl cylinder on your FEL but not a separate, third function cylinder, they're both cylinders after all so they should act the same, no? Where the regen function is an issue is for hydraulic motors, like those sometimes used to rotate a snowblower chute. A hydraulic motor will have equal force from both "sides" of a regen circuit and won't move correctly. Regen works for a cylinder because the increased area of the non-rod end will always overpower the force on the rod end. For a hydraulic motor, you need to push the stick to the right past the detent to get it to move in the opposite direction from pushing the stick left. Final note is that electric over hydraulic 3rd function valves have been installed on a lot of Kubota's to operate a grapple, for instance.
oldnslo
Super Member
If you push the curl past the detent it will still work, just more of a PITA to operate.
CHDinCT
Veteran Member
Just another thought, but worst case, you could split the boom cylinder circuit for your grapple if the Fasse valve won't work on the dump/curl circuit. Once you have the object clamped in the grapple, switch back to boom operation.
I do not know squat but I was thinking this very thing.
To curl bucket up move lever left.
To Open grapple hit electro switch and move lever left.
To curl bucket down move lever right as normal.
To Close grapple hit electro switch and move lever far right past detent.
(Will anything go haywire while passing thru that zone before detent posistion? Is it something a check valve can fix? )
Gosh, that isn't even a pita to me...ya think I can make this work? I so
want it to be a simple install, easy to maintain kinda deal. Not long hoses
hangin' all over the place.
BXpanded
Silver Member, Approved Advertiser
A CHD said, the Regen will work any cylinder as long as the line going to the non-rod end of Cyl #1 diverts to the non-rod end of Cyl #2. The dump cyl on the bucket is extending as the regen is in play. The grapple cylinder would need to be extending as well. In other words the control to the right would be extending the rod on the grapple cylinder. Keep in mind you will not have a great deal of power until you pass the detent.
