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View Full Version : Looking for some MechEng help...



shobley
06-05-2009, 01:51 PM
I'm trying to design a table that has a monitor 'embedded' flat in the center (a la old video game tables) but can be raised and tilted like a conventional monitor.

The tilting part I can imagine, I'm struggling to envision a "tilt and lift" arrangement.
Eventually I want to power this thing from some old 12v wiper motors I have.

Any resources out there for this kind of engineering?

Steve

darkback2
06-05-2009, 01:58 PM
I would consider a double hinge design...so you have a linear actuator that pushes against the plate that the monitor is fixed to. Once it tilts up to a certain angle, the first hinge locks, and the entire plate slides up on some sort of scissored lift.

You could also use two actuators. One for angle, the other for lift...though you might have to lock out the lift actuator until the tilt actuator reaches a certain level.

Quantum
06-05-2009, 02:50 PM
If all you want to do is change it from flat to straight up your really only need to tilt it. Throw a hinge that connects the bottom of the monitor to the table. Push up on the unhinged end. The bigger the plate that the monitor is mounted to the higher it will come off the table.

This wouldd work on a LCD monitor only.

nagmier
06-05-2009, 09:48 PM
This ought to turn out to be a pretty neat project, I would be concerned about what you are going to use for the surface of the table/screen protector, My concern would be assuming plexi or one of its buddies would scratch pretty easily.

Quantum
06-06-2009, 02:22 AM
glass

nagmier
06-06-2009, 09:42 AM
Wonderful assumption Quantum... seeing as he never states it I wonder where you get the confidence to just state it out right.

Glass would change the dynamic quite a bit. Glass is VERY heavy and not easily "machined" or bent to mans will

How big is the table "face" your talking about shobley?

shobley
06-09-2009, 11:53 AM
OK, thanks for all the responses.

I've been away pondering this and I think that you are correct, I don't need a "lift" just a tilt that pulls the monitor away from viewing obstructions.

I'm currently thinking about employing a worm gear to move a "dolly" on a track. This dolly would have a pivoting arm connecting it to the mount plate on the back of the monitor.

Moving the dolly along the track would (hopefully) pivot the arm and raise up the monitor.

Something like this:

http://www.stephenhobley.com/table.gif

Looking at it now though it I can imagine that the leverage is wrong, and this would subject the support arm to unnecessary stress.

I recently picked up a nice 26" monitor that has a flush glass front, with a VESA mount on the back.

The table top is going to be made from wood and sit in a steel frame borrowed from the existing coffee table.

I would not encourage people to put things on the monitor, and might make a cover to rest on top of the table when not in use.

Initially this started life as "just another MAME table", but the more I thought about it, the more I wanted to make something unique.

shobley
06-09-2009, 01:11 PM
Someone just brought to my attention that this is the same mechanism used in crank house windows.

Yay! Maybe I can buy some replacement parts for a window and adapt it...

Adrenalynn
06-09-2009, 01:18 PM
I suspect that's a great idea. If you go to the more commercial windows, they'll handle more weight, and some are geared up higher.