Idle Hands revisited

[OkeeDon]

I agree about the mast and winch setup; the out-of-control winch was part of what I was thinking about when asking how it would get back down. Even empty, I imagine the bed would come down pretty fast without some sort of brake arrangement. A simple friction cable brake might be enough.

I was thinking more in line with the idea of using the auto differential as a wind-up device as nuvz suggested; what actually occurred to me was using a transmission and differential mounted in a frame under the dump trailer, with a PTO shaft as the input to the transmission. Run the trans in 1st gear. Assuming a first gear ratio somewhere around 3.74: and a differential ratio of 4.10:1 (typical; the actual ratios wouldn't matter), you'd have an overall gear reduction of about 15:1. Assuming 540 PTO RPM, that would give you about 36 RPM output at the axles and plenty of torque multiplication. Weld the pinion gears so the differential applies power to both axles equally. The actual trailer frame would use it's own axles as rolling gear; the only purpose of the rear axle assembly would be to motivate the dump body.

Then, fabricate some sort of chain drive on the ends of each axle going to some sort of drive mechanism for the dump body, winding it up. You would adjust the actual speed by further gear reduction with sprockets. I didn't get far enough in my ruminations to get more specific. But, the idea is that you'd put the PTO in gear and the dump body would go up.

Then, you'd have to have some some sort of limit device, maybe a slip clutch of some kind, so it wouldn't want to go beyond the operating range. It would have to hold it in the up position while you moved forward to complete the dump. Then, there'd have to be some way to get it back down. My thought was to somehow get the transmission into reverse and "back" it down, maybe with a remote shift mechanism. The real problem lies in how to stop it, how to hold it while shifting into reverse, and how to release it before bringing it down.

Off the top of my head, I could come up with some solutions for all that, but I have a tendency to "Rube Goldberg" things, and before I set off on such a voyage I'd want someone with a more practical mind to come up with a simple, but elegant solution.

All of that just because I happen to have old transmissions and differentials laying around; I even have a 4.10:1 differential with welded pinions out of an old race car.

Hmm. Maybe leave the drum brakes on the axles, bolt the drive sprockets to them, and use the emergency brake cables to hold up the dump body until it is empty, the transmission is shifted to reverse, and it's ready to come back down. Or, let gravity bring it back down, and rig some sort of brake lever to actuate the hydraulic brakes already on the axles. A lever mounted on the tongue that can be reached from the tractor seat; operating a master cylinder at the base, and running regular brake lines to the axle assembly.

Put the PTO in gear, run it up as far as you want then simultaneously set the brake and dump the clutch on the PTO; disengage the PTO, pull forward until it's empty; then slowly release the brake until it safely comes back down. Yep, I love this thinking out loud stuff. Guess I'll put a little more thought into the actual chain drive mechanism to lift the dump body.

As for the title of this thread; I don't have idle hands or an idle mind. My problem is that my mind is always racing, but usually in weird directions... /forums/images/graemlins/crazy.gif

 

[BigEddy]

Gravity!

 

[Taylortractornut]

Baker Maney, and old Euclid 3 yard pans used to be like that, one wheel had a smooth wheel and seperate bearing in it and the other had angle iron cleats that grabbed the soil to drive the lift and dump. You can imagine how stout it was if it could pull a bowls cuttin edge out of the ground with 3 cubic yards of dirt.
I had and old farm book here that me and my cousin used to build things out of, one thing we built that was so usefull was a dump bed. I sat on 2 wheels and had an arch at the front over the hinged bed. Then we narrowed down an axle and differential and put a pto shaft from the tractor to the input on the Diff. We built a spool on one brake drum and just had the other drum for a brake. It hauled about 2.5 yards of dirt when you dumped it you engaged the pto and the side without the spool would free whel then you pulled that sides emergency brake and the spool wound up then you pulled the other lever on the spool and it locked the bed in the air. We moved about 80 yards of dirt with tis trailer over a weekend filling in a hard to reach swimming pool. Now that i know hydraulics the cable way is only a last resort.

 

[OkeeDon]

</font><font color="blue" class="small">( Gravity! )</font>

Maybe I should rephrase my question - how do you get it back down slowly? /forums/images/graemlins/crazy.gif

Taylor - that sounds pretty close to where my demented mind was heading. I was thinking about a welded diff and using both sides to lift. Maybe I'll try it some day, after I get my barn built so I have a place to work...

 

[rockinmywaypa]

I was thinking about a traler I made about 25 years ago to haul grain from the combine. basically an old manure spreader rebuilt to tip instead of using the gathering chain[ which was broke, that's why I got to play with it] and a jack-all in a shoe to keep it from slipping out of place at the front. Hauled a fair bit of grain and dumped it into the auger quite nicely. And with all my projects the price was pretty close to nothing.

 

[Taylortractornut]

Don on the welded differeintial youd have to have a transmission to reverse the spools. My nieghbors dad started thier construction company in the late 40's with a 39 Ford truck and trailer that had the winch hoist dump bed. It only hauled 6 yards and was a single axle trailer. He said at first it was always a good noise and jar when the trailer double blocked and she fell to the frame.

 

[OkeeDon]

Taylor, that's exactly what I was thinking - what occurred to me was that even running through a 4.10:1 differential, 540 PTO RPM would be to fast at about 131 RPM, so coupling the original transmission directly to the diff (no driveshaft), and adapting the PTO shaft the the tranny input shaft, and then running in 1st gear (typically around 3.74:1) would reduce the axle speed to around 35 RPM. This seems pretty manageable to me, without any experimentation, and the gear reduction would increase the load that could be lifted.

The other advantage is that once the load is emptied, the tranny could be put in reverse and back the dup bed back down. Shifting could be done with a long shifter from the tractor seat, or, if you were only using 1st and reverse, maybe a couple of solenoids. If you wanted a faster dump speed, you could shift the tranny to 2nd gear.

Once problem with a cble rig would be how to hold the dump bed up while disengaging the PTO, shifting the tranny to reverse, and engaging the PTO again. It sounds deceptively easy - just use some sort of pin or block or ratchet. Problem is, you usually have to lift a tiny amount to relieve the pressure to unlock it, and once you've set the thing to come back down, you can't lift it again. I've been wondering if there is some sort of long screw jack available in a junk yard that could be used for lifting and lowering, and which would hold the bed in any position when not turning.

For those who think we're nuts, remember the point of this mental (for now) exercise is to come up with something that is essentially free. Sure, hydraulics would be easier, but most of us don't have hydraulic pumps, motors and lines just laying around. I do happen to have some differentials and trannies, and even a couple of front wheel drive transaxles which might work better - more compact, and set up to shift with remote linkage.

 

[Taylortractornut]

Don stop take 2 steps back and think, the axle has 2 brakes and drums, just get a little master cylinder. thats one reason i like to use one wheel one side of an axle because you can brake one side and let it wind up, then lock the winch side and release the brake side. That provides the lift and hold. Around here tricycle front tractors had homebuilt loaders that used that configuration to hoist. Lots of pulp wood loaders worked like that to, even the infammous side loader pulp trucks. They could take a 30 inch oak log 12 feet long and sling them over an 8foot tall log standard. Its un ending at the things car alxes can do. Logging winches, pile drivers, pulp loaders, mower drives, fertilizer spreaders, post hole diggers, horse walkers.

 

[OkeeDon]

You've sold me. Mount two single chamber master cylinders on the front of the trailer with long hand levers to provide the leverage to operate them, one each plumbed to each drum. Engage the PTO. With both brakes off, the power goes to the side without a load and the assembly free wheels. Brake the unloaded side and power transfers to the winch side and the bed lifts. Release the unloaded side and brake the winch side (that's the only tricky part; timing has to be right) and the bed holds. Power transfers back to the unloaded side and it freewheels again. Slowly release the winch side and the bed comes back down at whatever speed you like. Adjust the RPM/torgue multiplication with the size of the winch pulleys and the need for a transmission is eliminated.

OK, you 23 year old genius, teaching a 63 year old new tricks, what do you suggest for essentially free running gear for the trailer frame? Should it be a wide tread, long wheelbase trailer like a hay wagon, or a short wheelbase tandem like the dump trailers used by roofers? I want it to be able to stand by itself while I unhook the tractor in order to use the loader to fill it, with a simple hookup when I'm ready to tow it to my dump spot and back. The short wheelbase tandem with a tongue stand is probably easier to tow, and won't need a steerable front axle.

 

[BigEddy]

How about a worm gear boat winch. Under $100, 3000lb rating, and they dont free-wheel when you let go. Crank it up, crank it down. Use a scissor lift under the body to multiply the 3000 lbs to whatever you need for your load, and mount the winch at the front. No need for diffs, brakes, all that stuff. Sure you gotta crank by hand, but it's not going to be hard.

Someone posted a picture a while ago of a trailer he made with a boat winch on the front. Looked like an oil tank on wheels. I don't recall whose it was, but I'll attach it here for reference. I'm planning on flattering him by copying it, hence my having saved the picture.
Big Eddy