Re: [CAD_CAM_EDM_DRO] Philips Washing Machine Motors

James Owens wrote:

> Hi All,
>
> I have some motors liberated from Philips washing machines. I intend using
> these as servo's, along with Gecko drivers and 400 line encoders, on my
> Bridgeport type milling machine. The plates are as follows:-
>
> 22 V 200
> 5 A 1.8
> 75 W 200
> 800 RPM 10500
> 85 rating 15 %
>
> These are DC voltages.
>
> As I understand it they will run from 22volts to 200volts @ 85% duty, which
> can be improved to 100% if I fit cooling.
>
> The Gecko Drivers are rated at 80volts max and I have been warned not to
> exceed this.
>
> My question is if I use these motors will the Gecko's do the job or am I
> looking for smaller motors.

You can't (at least I don't think you can). I'm pretty sure these are
either brushless DC or AC induction motors. The Gecko drives are designed
for brush DC motors. There are special retrofit brushless DC motors that
have a special controller so they can be attached to servo amps for brush
motors, but they are quite exotic and rare.

Anyway, if I'm off base and these ARE brush motors, I think they are
somewhat wrong for the application. Since you get only 75 W (roughly
1/10 Hp) at the low speed, you will need to gear down a bit. But, since you
need 200 V to get full speed out of the motor, you will have to live with
about
4000 RPM, and you'll only get about 1/4 Hp peak (making some guesses).

I'd try them with a DC power supply and see what sort of torque/speed you
get at intermediate speeds, and decide what belt ratio to try. Something
around 4:1 might be the best match. I should note that I'm using 1/8 Hp
(continuous) rated motors, and going to 1/2 Hp or so peak, and these would
leave most CNC machinists complaining about low acceleration and rapid
traverse speeds. It's enough for me, though.

Jon