bubble jet printer teardown & reverse engineering salvaged components - Page 1
Forum section: electronics / projects

author: jonovid
author_rank: Super Contributor
timestamp: May 25, 2017, 02:59:16 pm
content: interesting to find many bubble jet printers do not use expensive components like stepper motors.but use what looks like cheap DC motors (have just two wires)and an odd0.1mm step 6 pin incremental optical type encodersmade by avago part no on the body is N156313.this type of incremental photo detector array reads the plastic optical shuttle tape or plastic discwith its 0.1mm stripes pattern as the is not a absolute encoder the bubble jet printer cpu must reset the shuttle bylooking for a dot on the plastic optical shuttle tape end.its that "cluck" noise when the printer is booted up. to reset the position of the shuttle unit and print headsI am seeking to know the outputs of the Incremental Pulse but I have no schematic diagrams to help with the pin outs.my first question iswhat is the pin out for the N156313 encoder. can not find a PDF for this.I like use this type of 0.1mm encoders in my hobby projects. as DC motors are cheaper then stepper motors.it is the 0.1mm Incremental step and the Incremental Pulse pin output need to know.i have tested one unit and made a video-Anyone else salvaged this component, or used this cheap type of 6 pin incremental optical encoder?do you have a output driver circuit for it? datasheet?this not the same component. the two images are not the same body or part type as the Canon printerhttps://www.broadcom.com/products/motion-control-encoders/incremental-encoders-code-wheelsthe printer switch mode power supply is a sealed unit that outputs 23 volt DC at 600mabut most of the cheap DC motors run at just 6 volts. so this must be all phase width modulation.

author: james_s
author_rank: Super Contributor
timestamp: May 25, 2017, 06:54:36 pm
content: That looks like an ordinary quadrature encoder. This set up is very common, a DC motor with an encoder forms a servomotor which is both faster and cheaper than a stepper.You could probably drive it with this:http://elm-chan.org/works/smc/report_e.html

author: jonovid
author_rank: Super Contributor
timestamp: May 26, 2017, 01:39:59 am
content: Quotethanks for the link.so its a quadrature encoderI do value a second opinion on this.my goal is to build a 3 axis gantry system from used /salvaged components& maybe control it with an arduino as a microscope gimbal / or video camera mount gimbal project.my next test will be trying to tap in to a still working printer if I fine one dumped in the street, to get the voltags off the encodersbeforei do a full teardown in it.

author: james_s
author_rank: Super Contributor
timestamp: May 26, 2017, 02:31:01 am
content: They will be ordinary 5V or 3.3V logic, you should be able to work out how to wire one up without needing to measure one in the printer. They are nothing more than a pair of IR LEDs and phototransistors. The LEDs can be run in series with a resistor, forward drop is probably around 1.2V per LED.

author: tombi
author_rank: Regular Contributor
timestamp: May 26, 2017, 04:16:45 am
content: Could checkout this guy's blog as he seems to have done it. He is just using an arduino plus a motor driver to control it.https://youtu.be/XIUrnR8bLAI?t=1469Pretty amused at how well his metal cutout encoders work (earlier in the video).Tom

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: May 26, 2017, 08:12:13 am
content: Quote from: jonovid on May 25, 2017, 02:59:16 pmNot necessarily - at startup it could just run the head until it hits the endstop. The absolute position of print on the page within a few tenths of a mm doesn't matter.

author: james_s
author_rank: Super Contributor
timestamp: May 26, 2017, 05:10:30 pm
content: The printers I've taken apart have had a separate end of stroke sensor, usually an opto interrupter type with a little flag attached to the print head. The motor encoder is just a plain quadrature encoder.

author: janoc
author_rank: Super Contributor
timestamp: May 26, 2017, 07:42:45 pm
content: It is a quadrature encoder, indeed. The pinout will have two pins for the LED(s) and most often two signal outputs and a ground. Sometimes the LEDs share ground with the outputs, sometimes it does not, you will need to poke it with an ohmmeter to be sure.There is most likely also a linear version of it in that printer - a transparent strip with these lines on it read by a photosensor on the printer head carriage. It is a very common setup. I have also seen the head having the DC motor/linear encoder servo system but the paper drive motor being a stepper. However, that is a rare configuration.I have made these to work using the encoder mode of STM32F30x timers - you do want hardware support for reading these, doing it by polling or interrupts is going to make you miss ticks If you want to drive the carriage, a simple PID will get you going, I had mine achieve repeatable positioning within an encoder tick or two from the setpoint with only some "by eye" PID tuning. It is a fun learning exercise in motor control.If you google for "inkjet" and PID control, you will find a lot of projects explaining how to drive these things.

author: jonovid
author_rank: Super Contributor
timestamp: July 01, 2017, 05:18:52 pm
content: Quote from: james_s on May 26, 2017, 02:31:01 amQuote from: james_s on May 25, 2017, 06:54:36 pmfinally got the printer quadrature codewheel documentation. here it is.Small Optical Encoder Modules Digital Output from AVAGOpdfthe optical sensors from old printers and scanners that are NOT 4 pin Photo Interrupters but are 4 or 6 pin 0.1mm optical quadrature encoders.that you find inside many printers and scanners. you will need the 0.1mm slotted codewheel or codestrip from the old printer.this it it schematics by AVAGO , this link shud work as PDF as this is hard to find. this may be of help to others. hacking printers for projects.https://drive.google.com/file/d/0BwZTKiltzKYzTkkzd3pTcmFmVnc/view?usp=sharing

author: SeanB
author_rank: Super Contributor
timestamp: July 01, 2017, 08:03:16 pm
content: The DC motors are typically run of of a 24VDC supply, though they are run with some PWM through a full bridge to get more precise control. You can run them at lower voltage, but they will have reduced torque. 24VDC because the print head will use the 24V supply to run the microheaters in the print head, used to eject the drops used to print on the paper. you inkjet power supply will thus be a SMPS that delivers either 24-36VDC direct with a 5V converter on the board ( for those with a separate in cord power brick) or will have an integrated power supply, that produces a switched 24-36VDC supply and an always on 5V supply to drive the printer.