Can anyone suggest what sort of motor this is?

[Ian ParkinParticipant @ianparkin39383]

[Ian ParkinParticipant @ianparkin39383]

I have a need for a motor like this one

its dc 50v

it needs to fit in a smallish space hence its build (like a pancake)

[Ady1Participant @ady1]

Fan motor?

Apparently small computer fans are brushless for reliability

[Ian ParkinParticipant @ianparkin39383]

Sorry for got to say its about 7 inches diameter and the alloy bit is about 3.5 inches long

its a fairly powerful motor but i have no specs at all

its fused by a 15 amp so I’m guessing it draws about 8-10 in use so 500 watts or so

[BazyleParticipant @bazyle]

3 phase so probably designed for soft start. Variable speed fan application perhaps.

[Ian PParticipant @ianp]

Posted by Bazyle on 28/07/2023 12:44:55:

3 phase so probably designed for soft start. Variable speed fan application perhaps.

3 Phase, where did that come from?

Looks like a high torque DC motor, possibly a stacked printed armature as it has face commutator?

Ian P

[Ian ParkinParticipant @ianparkin39383]

Ian p

have you seen one of these before? What would it be called?

Ian p

[Ian PParticipant @ianp]

Ian

Put 'pancake motor' into Google images and see if you can identify yours

Ian P

[Hairy PeteParticipant @hairypete39644]

I would call it a pancake motor. Like this:

https://www.printedmotorworks.com/brushed-pancake-motors/

Or closer still, like this:

https://www.electronic-circuits-diagrams.com/store/LONGFORD-KOLLMORGEN-12CD-003-PANCAKE-DISC-SERVO-MOTOR-NNB-_155234707000.html

"12CD-003" seems to be thee part number.

[peak4Participant @peak4]

I've had a brief look, but can't find anything immediately similar.
4 pole DC high torque is a starting point, but I guess you need to look at the speed as well, unless you can tell from the driving circuitry whether it's a normal 4 pole, or some sort of a servo/stepper motor..
There might be similar stuff, but not the same, on AliExpress, though the CE marking and RoHs do look in the correct format for EU rather than China Export.

What's it from and what's the problem with it?

Maybe fully re-assemble it, take a few photos and try HERE, which will search Google, Bing & Yandex
https://smallseotools.com/reverse-image-search/

You might not find one the same, but if it puts you on the right page…………

edit, looks like Pete and I were typing at the same time; shame about the price though.

Bill

 

Edited By peak4 on 28/07/2023 13:28:15

[BazyleParticipant @bazyle]

3-phase. My mistake. I saw 3 brushes but now I look again there are 4.

[Ian ParkinParticipant @ianparkin39383]

Hairy pete

it is off a longford

[Ian ParkinParticipant @ianparkin39383]

That’s the type but surely there must be a cheaper replacement

[Ian ParkinParticipant @ianparkin39383]

From the site hairy Pete linked to this is what i need

Unique Features of Brushed Pancake Motors

Brushed pancake motors, or printed motors and Scheibenläufermotoren as they are known in Germany, have a number of unique features that make them stand out from other electric motors:

Size
The motor is much smaller and thinner than normal iron-core motors

Rapid acceleration and deceleration
The armature is very thin giving low-inertia and exceptional torque ratios. The result is extreme acceleration with a typical pancake motor able to accelerate from 0 to 3000 rpm in only 60 degrees of rotation. To achieve rapid acceleration and deceleration printed motors can handle a peak current of up to 10 times the continuous rating which would be impossible for iron-core motors without demagnetising

Zero-cogging
Printed armature motors are the only electric motor variant in the world with no torque ripple. A conventional motor has a tendency to prefer certain positions where the magnetic alignment is best. This is called cogging and creates torque disturbances. The flat armature motor is ironless and is thus intrinsically non-cogging. This gives perfectly smooth rotation at any speed with no ripple effect. Click here for a graph that explains this

Long brush life
Because brushed pancake motors have no iron core there is minimal inductance. The result is no arcing, because there is no stored energy in the armature to be dissipated during commutation. In an iron-core motor a lot of energy is stored in the magnetic field of each coil. When this field collapses, the energy tends to be discharged by arcing to the brushes and this wears them out. Depending on the application, the brushes in our printed motors tend to last as long as the bearings.

Reliable at high speed
Brushed pancake Motors do not suffer from arcing as thus can perform reliably at very high speeds

Instant torque delivery
Another benefit of minimal inductance is that the current flows into the armature extremely quickly (in less than one millisecond). This delivers instant torque

Flat torque curve
The ironless disc motor has a perfectly flat torque curve up to very high speeds whereas iron-core motors tend to fade at high speeds. Thus a small pancake motor may be sufficient where you would have to select a much larger iron-core motor to achieve the same torque at high speed

Easy to cool

[Ian ParkinParticipant @ianparkin39383]

from the machine maker its £2500

[Robert Atkinson 2Participant @robertatkinson2]

What's wrong with it?

[Ian ParkinParticipant @ianparkin39383]

Well it was blowing the fuse (15 amp) resistance between the leads was only 1 ohm on removing the brushes a strong smell of burnt windings..

i may strip it down next week just for a look but I don’t think these types can be rewound/repaired economically

in this machine it has to start for a preset time (sheets delivered) usually about 1 second then stop for perhaps 2 seconds then restart and do that for 12 hours a day…perhaps a better way would have been a induction motor running continuously via a clutch and brake

Edited By Ian Parkin on 28/07/2023 18:44:39

[peak4Participant @peak4]

I'm sure you've looked on the web, but did you spot these folk
https://www.pmwdynamics.com/pancake-servo-motor-repair/

Good Luck
bill

[Ian ParkinParticipant @ianparkin39383]

Bill

the customer needs it running asap so its up to them

they have 12 of these motors so it may be well to see how much a rebuild is

ian

[Author]

Posts