|
|
So, I thought i was alot smart than I really am. Trying to figure out a complex hoist design for a log splitter log lift table. I think it will need something like a 2 part system similar to dump body hoist. I just cant wrap my brain around how that would work. Specs:top of table is 48" from the groundbeam is 13" total heightstand off from beam needs to be 2"I am trying to make the table stand 90 degrees vertical for the travel position and still be able to rotate down to about 30 degrees-ish. i want the cylinder to be mounted underneath of the beam. Attached are some sketches. Please point me in the right direction.
Reply:If you only use the hydraulics to lift the table to horizontal (or a little higher) it will be much easier to do. Then pull one pin and stand the table up for transport allowing the cylinder to hang freely from the lift table.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:
Originally Posted by MinnesotaDave
If you only use the hydraulics to lift the table to horizontal (or a little higher) it will be much easier to do. Then pull one pin and stand the table up for transport allowing the cylinder to hang freely from the lift table.
Reply:Look at backhoe bucket linkages - they use a hydraulic cylinder to rotate close to 180 degrees.XMT 350 MPA Dynasty 280DXSuitcase 8RC / OptimaSpoolmatic 30AThermco Ar / C02 mixerAssorted O/A gear
Reply:
Originally Posted by lakedrum03
~ I am trying to make the table stand 90 degrees vertical for the travel position and still be able to rotate down to about 30 degrees-ish. i want the cylinder to be mounted underneath of the beam. Attached are some sketches. Please point me in the right direction.
Reply:With Plan B the cylinder could either "ride" with and beneath the lift table, or pierce the beam, either way, but be located mostly horizontal and perpendicular to the web when the table is approximately midway through travel. Can any sense be made of that description? Advantage with Plan B is that the cylinder "foot mount" used with Plan A could be eliminated.Plan C could have the cylinder parallel to the web, and actuating the lift via scissors link.If the geometry was just right, then the rod could rotate within the barrel as the lift traveled through its arc.Although I'm not so sure that rolling the rod is good for common AG cylinders.Plan C adds parts and complexity, but tucks the cylinder in and anchors it via the beam that's already there and doing nothing else.Last edited by denrep; 01-20-2017 at 04:40 PM.
Reply:cement pump trucks have some interesting linkages to rotate through at least 180 degreesDo not argue with an idiot. He will drag you down to his level and beat you with experience.
Reply:This is why I experimented with cardboard and thumbtacks before I commit to hard stuff. I did a complex folding mechanism one time and on accident I put the pins and cardboard links in the wrong place. Turns out to be the exact thing I wanted, and wouldn't have figured it out any other way, even with the CAD tools I use now.
Reply:The only problem I see is that unless you have a really wide wheel base it might flip over. Today everyone is building them with a very narrow wheel base so they can store them better. Sincerely, William McCormickIf I wasn't so.....crazy, I wouldn't try to act normal, and you would be afraid.
Reply:Lost my reply. That isn't going to work directly. Even if you got the angles right, you would need a telescoping cylinder. If you are willing to compromise on either the storage angle or the pinning/unpinning it gets easier.My name's not Jim....
Reply:Something like this may work, but you'll have to figure out the exact pin locations and cylinder stroke.
Attached Images
My name's not Jim....
Reply:Now I'm just adding to my post count.
Here's another option. How about storing/transporting with the table vertical, but down instead of up and have it fold in half for ground clearance. Then the cylinder mounting becomes pretty simple.My name's not Jim....
Reply:
Originally Posted by William McCormick
The only problem I see is that unless you have a really wide wheel base it might flip over. Today everyone is building them with a very narrow wheel base so they can store them better. Sincerely, William McCormick
Reply:
Originally Posted by Boostinjdm
Now I'm just adding to my post count.
Here's another option. How about storing/transporting with the table vertical, but down instead of up and have it fold in half for ground clearance. Then the cylinder mounting becomes pretty simple.
Reply:
Originally Posted by Boostinjdm
That isn't going to work directly.
Reply:
Originally Posted by denrep
Why not?
Reply:
Originally Posted by Boostinjdm
Stroke vs. body length vs. leverage vs. angle of rotation. It may be possible, but would be real finicky to layout.
Reply:This might make for a cool modification to existing log splitters or new ones.The table would be supported by perhaps two 1 1/4" round bar, arms, Sticking out maybe 16 inches, that the table would pivot on. You could put the table below the arms and have it hang on the arms too. That might be better. But I just wanted to share the basic design. Sincerely, William McCormickIf I wasn't so.....crazy, I wouldn't try to act normal, and you would be afraid.
Reply:The shaft the arms pivot on go right through to the other side of the main I-beam. On the other side you would just create two small arms and link them together. But they would be in sink with the arms on the lifting side. This way it would get it past that dead center on the lifting side. Sincerely, William McCormickIf I wasn't so.....crazy, I wouldn't try to act normal, and you would be afraid.
Reply:
Originally Posted by William McCormick
The shaft the arms pivot on go right through to the other side of the main I-beam. On the other side you would just create two small arms and link them together. But they would be in sink with the arms on the lifting side. This way it would get it past that dead center on the lifting side. Sincerely, William McCormick
Reply:
Originally Posted by lakedrum03
William - that is very cool. Although i worry about the amount of torque that would be needed to raise that table. It would likely kick the pump down into the lower gear, decimating the return time. but i guess that wouldn't really matter if it was raising the work piece.
Reply:
Originally Posted by lakedrum03
William - that is very cool. Although i worry about the amount of torque that would be needed to raise that table. It would likely kick the pump down into the lower gear, decimating the return time. but i guess that wouldn't really matter if it was raising the work piece.
Reply:
Originally Posted by lakedrum03
William - that is very cool. Although i worry about the amount of torque that would be needed to raise that table. It would likely kick the pump down into the lower gear, decimating the return time. but i guess that wouldn't really matter if it was raising the work piece.
Reply:How bout a simple electric winch with pulleys.68' redface64' redface78' blackfaceSquarewave 200Trailblazer 302Miller 12vsMillermatic 211Maxstar 150325 Xtreme Victor cut master 52Betenbender shear& brakeScotchman iron workerWellsaw
Reply:With 3-1/2" piston mine would kick into slow pump mode only when a very twisted crotch of something very tough. We no longer have Elm, that was the toughest! Based on pressure it was pushing about 12 tons in slow, perhaps six in high.The 150 lb block of wood you lift would be insignificant in comparison. The moving parts so close to the operator concern me, but then I think "This is a wood splitter, of course it has dangerous parts.Here, all the homebuilt hoists use a mechanism similar to an engine crane.You won't use it most of the time. Try to avoid it being in your way when not in use.WillieAn optimist is usually wrong, and when the unexpected happens is unprepared. A pessimist is usually right, when wrong, is delighted, and well prepared.His name's not Jim.Lincoln Power Mig 210MP MIGLincoln Power Mig 350MP - MIG and Push-PullLincoln TIG 300-300Lincoln Hobby-Weld 110v Thanks JLAMESCK TIG TORCH, gas diffuser, pyrex cupThermal Dynamics Cutmaster 101My brain |
|
发表于 2021-9-1 23:16:26