Is the motor used to move the cartridge a stepper?

[PraveenAlexis]

neo, i dissembled a printer and i found two steppers and a normal dc motor (a big one and its not a BLDC) but that normal dc motor was there to move the printer cartridge, i thought that the motor used to move the cartridge is a stepper. still i didnt get the point about motor types

how can i find a motor type?? for example stepper motors and BLDC motors

[Neo]

Hello Praveen,

I think You have identified it correctly. There are printers that comes with a DC motor to move the cartridge. However you might have already noticed a thin plastic strip with 1000s of tiny black lines? This is called an encoder. By using a photo-transistor, the distance travelled is measured using this method. Since the measurement is read back in this way, this is referred as a servo system.

Have a look at following images.
Linear encoder:

Encoder_strip.jpg (77.29 KiB) Viewed 11070 times

1 - Encoder strip (semi-transparent gray strip)
2 - Carrier belt (black and brown toothed belt)

Rotary Encoder:

Rotary_Encoder.jpg (18.63 KiB) Viewed 11070 times

In printers, the signal from these encoders are read by using a small circuit as below.

encoder_circuit.jpg (31.02 KiB) Viewed 11070 times

Finally a video which tells everything
[media]http://www.youtube.com/watch?v=LQFQ-sCsJWc[/media]

[PraveenAlexis]

Thanks neo