Need Hand Cranked Gear Box

Can a manual boat winch be converted to do as you wish?

As I consider, there must be something out there that already works without converting, but I can't think of one either.

[edit] "...a manual chain hoist type of thing, but there is nothing like that, that I can attach a shaft to..." Hmmmm, this sounds like the operating principle of a manual coiling service door.

A boat winch came to mind as well, but the way they are put together, generally it doesn't really have a thru-shaft. Do you know, are they strong enough for a 1600 lb vertical lift? Like I said, a chain hoist would be great, but again, can't attach a shaft to it.

Yes, like a service door. At least visually. But those actually involve a long tortion bar within a tube. So I can't put pulleys on it because the rotating part is not exposed.

"... But those actually involve a long tortion bar within a tube." Negative, rolling service doors work on a jackshaft.

Bingo! Look for "jackshaft chain hoist".

What would you know about doors?

Oh yeah... never mind.

Well... I contacted a company named Lift Master that does overhead industrial bay doors, and discussed the whole issue with them. That's who explained to me about the torsion bar thing I mentioned. And he could think of no other solution.

It seems that "jackshaft chain hoist" is slightly different, at first glance. And is actually what I was picturing in my mind. Hopefully it is different. https://www.garagedoorstuff.com/product/garage-door-chain-hoist-jr-jackshaft/

could possibly be what I seek. I'll have to give them a call.

At this point, definitely a GA though!

The garagedoorstuff link shows a lightweight version of what I am suggesting.

Yeah, people like LiftMaster make stuff for sectional doors... upward acting doors that are in sections (usually about 2 foot tall) and store open in more or less the same fashion as when they are closed (e.g. a residential garage door). A rolling service door is so called because it rolls around a shaft to store when open (the jackshaft).

Cornell Iron Works, Cookson, McKeon... these are the guys to contact that I am aware of. Every door is made to order, they shouldn't have any real trouble making what you need. These guys all work through dealers, so a trip to the yellow pages for a local guy might get better results.

That's a good education on lift doors. Thank you. Evidently, a "rolling service door" is what I was picturing when I had the idea. LiftMaster should have made me aware of that. I described my project to them same as I did here.

I started with Cornell Iron Works website. It looks very much like what I was looking for. Will be giving them a call this morning.

Good one. Thanx.

You're welcome my friend. Glad I was able to offer the idea.

Let me know if you need more info.

I'm having a hard time picturing what you're doing, but if I'm close, you may want to introduce some hydraulics. This can be manually operated:

http://www.toreuse.com/hydraulic-workshop-press-motor-or-hand-operated-hsp-110m-1500/

Here's another:

http://www.esskay-group.com/Hydraulic.html

This has potential. I may keep it as back up plan E. I'm already on plan C.

Hi,

What about these? Powerjacks they are screw jacks that can be connected with shafts to lift in unison.

Best of luck,

John

Right. I already went the powerjack route. All types of jacks. But there really isn't enough room under the slabs. there are other components in the way. The only jack that would fold flat enough was a scissor jack, and without complicated gearing and modifications, those can't be hooked together to lift in unison.

Pretty much, the only option is a lift from the top.

The reason for this whole thing is for maintenance. Lifted once every six months. And it is an after thought. It should have been designed into the original design of the machine. The designer had a different lift method in mind, but it turned out to be impractical. So we must be adaptive and find a fix to this problem. The winch idea is what was deemed best... if I can find the parts.

The only jack that would fold flat enough is a scissor? Ever hear of a Porta-Power? Put a rigid frame of another inch under those section plates, use two lines-lifts off of the same tube. 4"? No problems.

What about modifying an old 4 speed pickup transmission with a granny gear? You would have to devise some type of ratchet and pawl so it doesn't get away from you.

That is the right kind of mechanism, but I'm not an expert in designing a ratchet and pawl, to the extent where I'd want someone to put their arms under 1600 lbs supported by that ratchet. Not in the couple days that I have available to me. Hoping for an OEM item.

Worm gear reducers are widely available in various sizes, mounting options and ratios, and with various input and output shaft arrangements. The top right one in the picture below should be about right. It has a hollow output shaft and keyed solid input shaft. Maybe adapt a crank to the input shaft? You wouldn't have to worry about back-driving with most gear ratios.

You're right. There is no difference between a manual reducer and a powered reducer except the crank handle. This may be it. For 1600 lb, maybe like a 30:1 ratio. On a 1.5" dia shaft, that seems like it would work pretty well. Easy enough to mount on a trolley.

Anyone see any issues with this?

If not, looks like Doorman and bigg have both been a big help. Thank you.

Just another thought...

If you were able to use counterweights, you would be able to get by with a very lightweight cranking mechanism.

Good idea. Except at the midpoint of shaft. Might do this.

Realize that I'm late, but this may be another idea. You may need an intermediate gear→

Helical gears
Top: parallel configuration
Bottom: crossed configuration

Chain hoist. Just cut the lifting chain. Loop it to itself to make a belt and run it to one of theses. http://rpscoinc.com/chain-sheaves/.

I'm sure one of these can be machined to fit the shaft.

Big worms, big sprockets, big chains; the red "bushing" like thing is a ball carriage (you'll need 8).

We lift 12,000 pounds like this everyday; ask Perfecto, a material handling machinery manufacturer, for the punch presses stock rolls.

Okay, just ran the worm gear reducer idea through. That was the best idea. But after spec'ing out the ratios and configuration, "the man" doesn't want to spend the $1600 on the one I need.

So that one is out. Lots of good ideas here. I'll be running through them one at a time. Thanx folks.

If the company doesn't have the money for that, the elevator should be simply put on hold 'till the budget heals; instead of having to improvise a maybe not so safe solution.

But if "the man" just thinks 1600 dollars is too much to spend on any part of the machine, well, things are much worse...

What happened, did your company issue a quotation on advance, before carefully considering the design ? and now you're tight on cash ?.

It's not just $1600; that is the price for the gear box only.

The machine is built and is due for delivery. The feature that was designed to raise the platforms does not work as was hoped. We are adapting by finding an alternate method.

The project was handled properly. Sometimes new custom built designs don't work on the first try. That's the nature of the business.

The custom machinery business is so much fun!

Have you exhausted all potential sources for the worm gearbox? Did you try Rhino or other imports? The worm gear adds the added feature of not back driving at higher ratios, which is good for safety of your personnel and gear.

Have you considered mounting 2-4 chain hoists to your frame and driving them together with a jack shaft? We lift big plates with a crane and spreader and 4 chains safely pretty regularly. When not in use, store the rigging out of the way.

I believe the gear box your looking for is called a torque arm, shaft mount reducer.

Most come with taper bore for a shaft adapter.

Thank you ozzb, I'll look into this type of reducer.

I do not know what country your from so knowing the agency that over sees safety is a guessing game. But, I see a hole lot of issues with raising a plate as you have stated. Are there persons going to be working under and around this equipment while suspended? If so you have now opened the other can of worms.

I would not venture to offer any suggestions for this issue other then to suggest finding a good qualified engineering firm to work with you so all bases are covered. Then you might speak to your insurance carrier before proceeding.

We are a good qualified engineering firm; not a bunch of guys working out of a garage.

I'm asking for creative ideas about a design challenge, from anyone interested in offering clever suggestions to help out. That's what we do here... Not asking for legal warnings and lectures. If you have reservations about offering ideas, feel free to not participate. Thank you.

OK, so you want cheap. Around the turn of the last century there was the problem of pulling up tree stumps from the ground. So what was devised was a frame like you envisioned, the 2" or so turning shaft had a HUGE wheel attached to one end, like 10 feet in diameter. Then a team of horses pulled the rope or chain wrapped around the big wheel. Substitute a cheap wire winch for the horses. For safety,throw a pair of railroad ties under the slab ends. If the ties get compressed go for 2 at each end. If you need a big wheel at each end of the torque shaft, ok go with two winches.

This may be an extreme Keep It Simple Stupid, maybe too stupid....

Do you need a gear box at all?

If you make the axle 1" diameter and the crank handle 16" long then you only need to apply 50 lb force to the handle to lift the 1600 lb slab.

Just ensure that the slab has safety blocks placed under it to ensure that it doesn't fall while working under it.

How about some air bags?

Thank you. Actually, that's been considered. The space that we have available below the slabs doesn't lend itself to that because of its size and shape, and other components in the way. Jacks and actuators were also considered.

I've described what my frame looks like, but those were just the relevant components to this discussion. There is a whole lot more to the machine. The envelope within the frame is pretty full. But we do have room above, that's why I'm looking at a winch type assembly now.

Don't forget to add a ratcheting BRAKE!

Yeah, that's partly similar to what USBPORT sketched out for me yesterday, except for center drive.

I just sketched a design like what you described. It makes sense. I might go with this.

sorry USBPORT, I missed your post; just added a GA for it

You could do this with a hand-cranked boat winch and some pulleys. From the main cable on the winch, make a crow's-foot of four extension cables, each running over pulleys to suit the geometry of your assembly.

Thanks for the feedback.