Re: Adhesives that can be "switched" on/off repeatedly?

From: tadchem (tadchemNOSPAM_at_comcast.net)
Date: 12/31/04 

Date: Fri, 31 Dec 2004 06:38:06 -0500

"Scott Smith" <scottseansmith2_NO_SPAM@NO-SPAM.hotmail.com> wrote in message
news:VR7Bd.55714$gd.13465@twister.socal.rr.com...
> This is probably a stupid question...
>
> I'm wondering whether there is some material or device that can be
> "switched" between having adhesive properties, and not behaving like an
> adhesive at all.
>
> The switching mechanism could be anything, but it needs to be fast,
> repeatable, and ideally it wouldn't consume resources (i.e., no using a
roll
> of Scotch tape). A material that became sticky when an electric current
was
> applied would be ideal.

Velcro?

How about a pair of magnets? One permanent and one with an electric oil -
energizing the electromagnet to oppose the polarity of the permanent magnet
would cause the two to repel each other enough to separate them, and then
you turn the power off. They would adhere on contact with the power off:

perm, electromagnet
magnet

N<--->S :------: not energized = adhering

N<--->S S<---->N energized = repelling

Depends on the intended application...and what you mean by 'switching'...

Tom Davidson
Richmond, VA

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