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Unread 11-08-2010, 14:47
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Al Skierkiewicz Al Skierkiewicz is offline
Broadcast Eng/Chief Robot Inspector
AKA: Big Al WFFA 2005
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Re: Remote operation of motors

Richard,
I believe the specification relates to the non-linear force as the moving part of the solenoid moves through the magnetic field. The maximum force occurs when the armature passes through the 1/8" part of the total stroke. In most cases where you are positioning a mechanism, you would not want the armature to make full travel. Instead position would be controlled by something external like an adjustable mechanical stop. You would then design the system to make use of the max force specification. I think in your case, this will not be an issue. Once the table begins to move, you don't really care if the armature bottoms out or not. If it does, that just adds to the noise. You can turn the pull solenoid upside down and attach a bar. When it pulls in, it will move the bar against the floor thereby raising the table. If you put one in each leg, and adjust them to contact the floor at different lengths, the table will have an other worldly look when it raises. I think you only want the table to move a 1/4" or so. Just enough to shock the audience but not enough to tip the table over. If the table has a nice long tablecloth, then you don't even need to hide/camouflage the solenoids.

"Bear in mind that if you used a CIM motor you would have vibrations in the 90hz range" James you will have to explain that one.
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Good Luck All. Learn something new, everyday!
Al
WB9UVJ
www.wildstang.org
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Storming the Tower since 1996.