Lift Idea Using an Electric Winch

[tc-cad]

Hello All

I have an idea and would like to get a discussion started. I like the design of the Scissor type lifts on the market. The mechanics of the lifts seem to be a pretty simple and similar design. The expensive part of the lifts to me seems to be the Hydraulic pump and cylinders and related hose/tubing. What if a design was done using the same basic principle but for power you could use an Electric Winch. A winch can be purchase at almost any weight capacity you can think of. I have seen pricing for winches any where from $300 -$600. In a production garage I can see where this would be a very slow lift operation but in a residential garage I think home owners can live with a little longer time frame to lift their vehicle.

Of course people will say that the cable can snap. True, however some lifts already use cables in their design.

I know some lifts use aircraft cable tied into a hydraulic cylinder for power.
Can any lift owners chip in and tell us what size (diameter) the cable is for their various style lifts they may have that use aircraft cable?

Another idea I have is to use the winch to drive a worm gear to raise and lower the scissor type lift. But now you are incurring the cost of a worm gear, possible but could be costly. The worm gear would act as a saftey lock at any level, which is a good feature.

Thanks
I hope to get a lot of discussion on this topic?
Any engineers out there interested in teaming up to build such a project?

TC-CAD

 

[spy604]

The advantage to hydraulic scissor lifts, is that they can be valved in such a way that prevents the lift from collapsing even if a hydraulic line blows out. Post lifts have a locking mechanism. A cable driven scissor lift wouldnt have any means of safety protection should the cable fail.

Now the worm gear/lead screw would. Many lead screws are self-locking, meaning that they cant be back-driven.

Edit: engineer here

 

[brownbagg]

i think you need to forget what you are thinking, even a china made cheapy lift is better than what your thinking

 

[spy604]

what might work would be a gear rack and pinion, instead of a lead screw. The motor/reducer could be attached to the lower moving axle of the scissor. A lock-out mechanism could be attached from the axle to the lower frame.

I would call that marginally safer than the cable idea, but you still wouldn't catch me underneath it. Either way, the hydraulics are the safest, and aren't really that much more expensive.

 

[kbs2244]

It has been done in the past.

The described safety problems drove them off the market.

 

[Stee6043]

I've got a "cable operated" 4 post lift with the single hydraulic cylinder. I'd guess the cable is 1/2" diameter, maybe a touch bigger. There are catches every 4".

I wouldn't put anything I care about on or near a lift that doesn't have some kind of safety stop design in - this is for sure.

 

[PittsS1]

Hello All
A winch can be purchase at almost any weight capacity you can think of. I have seen pricing for winches any where from $300 -$600.

Any engineers out there interested in teaming up to build such a project?

TC-CAD

You may be able to get into a hydraulic version cheaper than you think... check surplus center:

https://www.surpluscenter.com/sort.asp?catname=hydraulic&keyword=HPPA

Valving is quite simple in these lifts. I'm a mechanical/hydraulics engineer, but have WAY too many projects already...

 

[rsanter]

The cost of the lift is not in the hydraulics. Hydraulics are relatively cheap for the power they provide.
The cost is on the design, engineering, and the liability. You are in the typical place that many of us mechanical types are. We look at something and say why is that so much, I could put one together for half that cost.
That may be true but I bet you couldn't do the engineering, design, building and then cover the liability in order to sell them.

For you alone at home as a one off. Buy a surpluss or used one or directly copy someone else's design for your own use

Bob

 

[tc-cad]

Guys thanks for all the input. I can see the benefits of the Hydraulic design. Thannks Pitts1 for the great pricing of hydraulic units also.

I think its back to the drawing board..........again.

TC-Cad

 

[Maexle]

i am an engineer, and there is nothing wrong with your idea, cable can take a lot of tension force. As long as you think carefully about some built in safety features it'll be alright for home use. Catches (like ratcheting brackets or something) could do the job easily. The only Achilles heel with this idea would be to re-direct the direction of the cable. The winch at the floor, a pulley at the top of the lift poles and here we go. Another thing to consider is, how do you lift all 4 / 2 sides absolutely equal. If one side is just a 1/4 " higher, most of the force is right there, so you have to come up with a central cable which spreads out to the poles, but this means more pulleys to redirect the force, this again means tension spots, this again means a lot of force at these specific points, this again means $$$ to get a sturdy, ridgid and safe design.

Safety stops can be done in many ways, ratchet like, conical, excenter, spreaders....etc....think about elevators, all cables (BUT again, they use straight directions (pulleys to redirect)).

The cable is not the problem, but the pulleys, axles, bushings, etc...etc....

Perhaps it's time to think outside of the box, why not doing it like lots of people in Germany do it (low garage sealings...etc...) cut open the concrete in your garage, digg a pit in your floor, good foundation, concrete walls and cover it with hardwood. A 2 ft wide and an almost garage long pit with stairs down and you can drive your car above it and work nicely. When it's not needed, cover it up with the wooden planks and no stumbling over the lift.

 

[rslaback]

why not doing it like lots of people in Germany do it (low garage sealings...etc...) cut open the concrete in your garage, digg a pit in your floor, good foundation, concrete walls and cover it with hardwood.

Homeowner's insurance.