dual vertical acme screw / single motor

[skyfish]

I'm trying to work out a plan to raise a window with a screw. I am not too familiar with the nomenclature. I have searched through the archives and not found anything similar.

There are a lot of windows, so I am trying to keep the total components to a minimum. Actuators are too expensive and cabling is to messy. I was thinking a right-angle gearbox with two outputs would connect to the input of another single output gearbox whose output is the screw. The window is approx 40 lbs and the screw will have to be 7-8 feet long. I have crunched some of the numbers (torque, etc). The window will be held in a track with rollers.

Is the dual output gearbox unnecessary (dual shaft motor)? I liked the modularity of the gearbox if the motor fails.

Any comments on workability of solution or alternatives would be welcome.

skyfish

[vger]

Some time back I took a large tredmill apart. The incline adjust mechanism was a motor coupled to a right angle worm drive with double output shafts. Those 2 shafts were linked to a pair of boxes that created linear motion of some large acme thread rod. Inside the box was another worm and wheel with acme threaded hole in the middle of the worm wheel.

Perhaps a mechanism similar to the actuator on an adjustable bed would work for you... longer of cousre.

Steve

[ger21]

Chain and sprockets? Or belts and pulleys?

[vger]

Neither. All direct linked via lovejoy couplings. Of course you would need a linking shaft to span the width of the window.

Steve