Equipment elevator level platform

[macatc123]

Hi, I have a project of designing an elevator type structure to lift a 40lb payload about 6 inches. Due to space constraints, I would like to use a sleeve style adjustable air spring (see link below) in the middle to provide the lifting force, and have 4x 1" shafts (one at each corner of the platform) and linear bearings to guide the platform. The goal is to have the platform lift relatively level, and not bind up. Does anyone have experience in a similar design? I know there are many ways of doing this but I am trying to minimize cost. Do you believe this idea will work? I appreciate the feedback. Thanks

The platform is about 35"x35" and .25" thick

Mac

http://www.mcmaster.com/#pneumatic-lifts/=hd5x5k

 

[Jboggs]

If you are planning on using linear bearings to prevent binding and you can't space them out along a common shaft, you are asking for trouble. They provide lateral guidance only and are generally not very good at resisting a twisting moment. That is one of the most common mistakes in their use. I would examine some type of scissor mechanism. That way no one corner would move without the other corners moving with it.

Do you have any space at all available above or below your envelope of operation? If so, you can incorporate some better guides.

 

[tygerdawg]

Sounds like you are designing a Danly die set, of sorts.
The trick is to get sufficient L/D of the bearings to alleviate any binding. Also, 0.25" thick is likely to flex (causing misalignment & binding) so you may consider adding stiffeners.

TygerDawg
Blue Technik LLC
Virtuoso Robotics Engineering

http://www.bluetechnik.com

 

[macatc123]

Thank guys, yes it is similar to a Danly die set. Here is a picture of the concept. The top plate will be lifting the payload and the four shafts with linear bearings on the underside will guide the plate. This is the linear bearing I would like to use.

So, all I want is level movement without binding. I increased the plate thickness to 5/8"

Mac