On Sat, 23 Feb 2002 21:43:14 -0600, michael brown wrote:
>
>I got them from a surplus store here in houston.  They seem to
>have come from some type of medical machine.  There is a nifty
>assembly attached that with about 15 or 20 little "fingers" in=
 a
>line.  When the motor turns, the "fingers" move up and down in=
 a
>moving sine wave type pattern.
>They were used as a pump in some type of dialysis or bypass
>machine.
>

I have designed a few of these medical devices -- what you have
is a linear peristaltic pump mechanism from an infusion pump.

A flexible silicone tubing set is fixed in the mechanism and (as=

you described) the "fingers" move up and down. As they move, a
segment of fluid is continuosly trapped and squeezed out of the
tube quite precisely. The rate of delivery is set by how fast the=

microcontroller drives the fingers up and down.

Matt Pobursky
Maximum Performance Systems

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