HURCO Air, Oil &E-stop

**Jonss** · 05-19-2022, 05:42 AM

Hello guys

Im new to this forum but I feel this will be a very huge help.
I work for a watch component supplier. We work with a lot of old, yet great machine, and a lot of old and weird/outdated machines.

My job is to retrofit these machines.
This is quite problematic when we start to modify old machines with suppliers that do no exist anymore or old CNCs.

Anyway, our subject here is an old Hurco VM1.
It works good, a few modification were made to use it for grinding sapphires.
However, there is one thing I dont understand. Maybe there is a reason but I honestly can't find the logic behind it:

- If you stop the machine via emergency stop/power outage, all the axis stop in place. No issue.

- If you have a failure of the air pressure (air compressor stops), or of oil pressure (never happenend), the machine would stop. And then, that's where it gets weird, after a few seconds, the Z (vertical axis) goes back up.
In my opinion it's plain stupid. If the tools are working at this moment, we break everything (happened last week).

I checked the electrical drawings and I can just get the airpressure sensor and place it on the EmergencyStop circuit. Same for Oil.

(2nd weird thing is the Machine homing. Instead of going to X=0 Y=0 and Z=0, the machine goes to X=0, Z=0 and Y=355.6 (it calculate the 0 according to this maximum position). Pretty messy)

Do any of you have an idea of why would they build the machine like that?

Thanks
Jonas