50 88lbs Plasma TV mount on Stand - Free Body Diagram

[plasmatv]

50" 88lbs Plasma TV mount on Stand - Free Body Diagram

Hi,

I am building a customized stand for my palsma tv. I already have the base, made of 2" square iron tubes. I am about to design the mount for the screws, but I was wondering what forces should I consider for this.

The base is in an "H" shape with a center pole rising about 4 feet tall (the whole structure of the stand is welded). The TV will be mounted with screws in two horizontal square tubes. These two horizontal tubes will be welded to the center pole, so the forces will be acting downward to the middle of the "H" base. The base has four wheels for easy displacement. The wheels have breaks.

What forces or torques should I consider to avoid the tv to tilt forward or brake loose from the screws because of the tv's own weight or creep? I took this in college a long time ago, so I'm familiar with the terms, but I can't remember the process to analyze this.

Thank you!

PS: Sorry for the quality of the sketch! :P

 

[nvn]

plasmatv: You say the base is made of 2 inch square tubes, but your diagram says 1 x 2 inch rectangular tubes (and does not designate the cross section orientation for each member). You give no wall thickness of the tubes. You give no dimensions in your diagram, and no detailed views showing how the welded connections are made. You say the tubes are iron. Are they really iron? Or are they regular mild steel tubes, which are more common? Do you have a material specification for the material of your tubes? You do not give the horizontal offset dimensions from the TV center of gravity to your tubes. You only state the mast height (presumably from tip to tip), but you do not give the location of the welded connections. You give no locations nor details of the bolted connections, nor the bolt size and material grade. How is the connection of the mast to the H reinforced? Does this connection have triangular stiffener (gusset) plates? Do the upper horizontal tubes (or any other joints) have gusset plates? Can you provide the above information and dimensioned diagrams or dimensioned sketches?