Re: [CAD_CAM_EDM_DRO] Servo Motors....?

baccus61 wrote:

> Hi Gang,
> I am enquiring about a couple of motors I have pulled out of
> Risograph high speed printers.
> These are gear motors with the following specs.
>
> DC 24 volt
> 5 Amps
> 150 Revs
> 43 Kg/cm
> 1:24 Ratio
> serial# = 3022G-24F-9K24F
> Tokushu Denso, Japan.
> Forgetting about the revs, torque etc I would like to know if they
> would be suitable for a servo driven router, minus the gearbox of
> course. They have a rotory encoder on the rear with 120 slots and a
> 3 wire connection to the pickup (red,white,black), they have brushes
> on the armature and are about 3" dia and about 4" long over the motor
> body excluding the gearbox and two wire connections (Red,Blue).
>
> What type of driver would be suitable for these if they are in fact
> useful and if the encoders don't have enough resolution then could
> the motors be geared down with tooth belts to reach a useful
> resolution.

24 V x 5 A = 120 W. if that is continuous rating, it might be adequate.
If that is the peak rating, they are too small for any use like this. The
armature RPM is 3600, not bad. You might be able to get a bit more
power out of them at higher RPM. You really need to determine the safe
peak current before going much further. If you exceed that, even for
an instant, it demagnetizes the permanent magnets and seriously degrades
the motor. The "encoder" you mention is a tachometer, only. With 3 wires, it
has power, ground, and only one signal. You need two sensors in quadrature
to determine direction, the basic requirement for a position encoder.
Motor torque will be 43 Kg/Cm / 24 = 1.79 Kg/Cm, which isn't too exciting.

Gecko drives or analog servo amps can be used to drive it.

Jon