Fw: Magnetostrictive sensor DRO

-----Original Message-----
From: Uptown Gallery & Frame Shop, LLC <uptown@...>
To: CAD_CAM_EDM_DRO@egroups.com <CAD_CAM_EDM_DRO@egroups.com>
Date: Wednesday, April 12, 2000 5:45 PM
Subject: Magnetostrictive sensor DRO

>Has anyone ever run into one of these?
>
>At my last 'real job', the company made underground storage tank level
>sensors. A stainless steel tube with a special nickel alloy wire

(Ni-Span-C)

>with a unique thermal coefficient of expansion characteristic inside spans
>the distance to be measured. A non-contact annular (toroid or
>doughnut-shaped) magnet is connected to the linear translation mechanism

and

>induces a magnetic stress in the wire corresponding to its position. The
>wire is 'twanged' like a tuning fork and an echo or reflection is induced

by

>the magnet's position.
>
>By measuring the time delay, the position of the magnet can be determined.
>It's not a DIY device, but I was told it's origin was the CNC machining
>industry. They can be immersed in liquids including gasoline...I don't
>recall the accuracy...seems 0.0005" was what they were talking about, but
>that's measuring the depth of liquid in a 10-15-20 feet tall tank, so in
>that situation it's more than adequate.
>
>Magnetek in the Royal Oak (Detroit suburb) area in Michigan seemed to be

the

>big foot in the industry, if anyone wants to pursue it.
>
>Murray
>
>