Re: Re: Brushless DC servos

Raynor,
Since most of my parts came from cleaning out an
office place, I can say a little here.
Most of my parts have come from copiers,
typwriters and such. I have investegated these
copier motors and drivers myself. Some have some
very good Step motors in them and I have seen
linear type though the rez and power is not known
yet.

The 3 phase BLM's have internal hall effect
sensors for
feedback to the driver and most of the circuits
are designed for constant speed running. I have
noticed 2 mechanical types,
the difference being internal and external rotors.
I have activated them using 3 inputs available on
the controller which are "RUN, Direction, Brake".
The speed is externally controllable, and this
circuit I have not messed with much.
They are amazingly fast and will reverse on a
dime. The internal rotor types have to be held
very tight when testing due to the torque
generated at start and reversing. Right now I see
software being the problem for using the BLM type
for axis use, but I hope to try and develop a mini
spindle use some day..
BTW Olevetti Typewriters have complete hardware
for a small router system using Step Dir software.
There are some Richo collators that have a Vexta
motor and 297/298 ready to hack in the digital
signals, I only have one of these hoping for more
to show up.
Raynor Johnston wrote:

>
> From: "Raynor Johnston" <rhj-rbj@...>
>
> I have a quantity of "D.C. Brushless servo motors ex photocopiers being 30
> vdc 21dca and 39 output watts.

<<snipped some>>

> Raynor Johnston (NZ)

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