Controlling a Vacuum Extractor for a CNC

Other Hardware Motors, Mechanics, Power and CNC
1

Hi all

I have a CNC machine and an extractor which pulls out dust etc while the CNC is running. With that said sometimes the CNC finishes it's job and stops - know that it won't always return to the same point of origin - noooo - that would be TOO easy! SO when the CNC stops its run it returns to the 0 point set for THAT job and stops. The extractor, however, has no intelligence and continues to run regardless.

I need to find a way that I can have a movement sensor OR some sort of sensor that would turn the extractor off when the CNC has stopped. Typically that would mean all 3 AXIS will stop moving. Is there a way to do this? I have a UNO and a 2560 laying around but i think an UNO would be more than enough.

Any ideas/links etc would be MOST welcome!

Thanks.

2

Would a current sensor allow you to tell by the overall system's draw, whether you're seeing the CNC machine at work as apposed to just the fan?

3

Why not power the extractor when the spindle is running ? this is the way commercial systems work.

// Per.

4

what cnc program you running

5

I am using NCStudio. I know some cards like Mach3 have a pin out that can be used to trigger a relay etc which would be the easy way - VERY easy way. However I don't think NCStudio has that ability.

6

shearder:
I am using NCStudio. I know some cards like Mach3 have a pin out that can be used to trigger a relay etc which would be the easy way - VERY easy way. However I don't think NCStudio has that ability.

Once again i ask: Why not power the extractor when the spindle is powered ?

// Per.

7

You could XOR all the step pulses together and hook that to an interrupt pin. Interrupt
handler resets the time-out value, main loop waits for time-out to happen. Or route the
step pulses to several pins on the same port and use the relevant pin-change interrupt.

8

That would be a very logical thing to do. How would i go about doing that? would it not compromise the workings of the spindle which is controlled by an inverter? I am not sure if it uses PWM etc - whether it is relevant or not is also beyond me however how would i do that as it makes the most sense as the extractor is only required when the spindle is running.

Zapro:

shearder:
I am using NCStudio. I know some cards like Mach3 have a pin out that can be used to trigger a relay etc which would be the easy way - VERY easy way. However I don't think NCStudio has that ability.

Once again i ask: Why not power the extractor when the spindle is powered ?

// Per.

9

What signals the inverter to start the motor ? This signal can activate a relay too, and then control the extractor.

If in doubt, post what kind of inverter drive you have, and what kind of interface you are using on the computer.

// Per.