Toyota embroidery machine - retrofit

thank you for your feedback.

indeed,

- it's a 0-5K ohm single turn potentiometer.
- on the 2 X and Y axes there are
- there is no limit switch.
-Since it's a single turn, I assume (not tried) that 1 turn = the distance the axis moves.

Thanks for the procedure, I was going to ask if it was possible to homing with a potentiometer.

Which reasoning do you think is best?

     - when homing, the motor runs until the potentionemetre is read at 1 ohm, then it looks for the incremental encoder index?

     - No homing, the encoder reads the potentiometer value directly?



I have a question about the needle motor control.

I have this electronic component, I suppose it's an encoder because of the markings next to the wires. A (Phase A) Z(Pulse) G(Ground) V(VCC) B ( Phase B )
Can you confirm this?

 

 

If yes, I suppose that I control the speed of the motor for embroidery and the position for changing the head (I have 5 heads).

However, I don't have a reference for this one. What test would allow me to know the number of pulses for this encoder?

For homing I would meassure how much the resistor value changes for one motor revolution. After that one can think of solutions. That said. It would be a good step to identify the ratios of the axis.

For the needle encoder. Plug it to a mesa card (first test with bench power supply and oscilloscope) and turn 10 revolutions....

To be honest. I think I would ad a lever and a switch for homing (plus index). But it depends. Maybe you want to have it as original as possible?

Would a compartor with some sort of reference changer circuit that changes triggering voltage based on motor dir work?

When motor dir is positive, it sends a positive limit signal when it spin too far.

When motor DIR is negative, it sends a HOME signal when the axis reaches the HOME location.

(comparator + NAND?)

Will post schematic.

Might be cool to make a switch circuit for homing with potentiometers tho, just sayin'.

i'm sorry i'm back so late, i was in the middle of cleaning the machine.
i think i'll keep the potentiometers, because i've never coded a homing with an encoder so this will allow me to improve, and if i never manage to, it's easy to dismantle so i could insert home switches.

 

I'm trying to identify each component to find out how this embroidery machine works.

I have two rotary solenoids that operate elements in the bobbin.

I presume that this lever locks the bobbin. Is this correct?

 

For this component, I'm not sure. At first glance, I have the impression that it cuts the thread, but I have a rotary solenoid on the upper arm.
The way it works, when the rotary solenoid is active, it engages the system and the component moves back and forth when the needle is up and stays in the position shown in the photo when the needle goes down and up.