[ltpm44]

Have taken possession of a 5 axis machine that has the x,y and z stepper motors on a closed loop system missing. The steppers on the spindle are there. The control box has all the drivers and all the cables. It uses a racket and pinion system. The stepper motors are from oriental motors and that model is discontinued. I have gotten all kinds of advice most want me to replace everything all 5 steppers plus drivers. which is a fair amount of money. My question is can a stepper motor with the same specs. as the original stepper motor work in the system or does it have to be the same manufacture and the same model number on the motor. The info I have gotten so far is that can't work if its not the exact motor. This machine is a 2014 unit so not to old but 6 years could be for technology to pass it by. Any help would be appreciated

[ger21]

If they are closed loop drives, then you need the right motors and encoders.

[joeavaerage]

Hi,

The stepper motors are from oriental motors and that model is discontinued

There is a company Oriental Motors, also called Vexta, that have a long history in making high quality steppers.
In particular they have a strong tradition of making 5 phase steppers although as I recall I do not think they have ever
produced closed loop steppers.

Can you be more specific about the steppers you have, model codes, specs...even pictures?

Craig

[ltpm44]

Craig
The system is an oriental motor system. It uses ASD30AA drivers and ASM98AA-T7.2 These are the three mortors that I am misssing. This is a closed loop system I have the drives and wonder if there is any alternate motors that could be used with the drivers. If another company's motor has the same specs as the oriental motor would it work.

[ger21]

They should, if you have the correct encoders.

[joeavaerage]

Hi,
looking at the published data for that motor I agree with Gerry that if you could fit a 1000 line encoder to a stepper then you might be able to reuse the drives.

The real problem is the gearbox on the motor, the output shaft is not centered, therefore any replacement stepper, irrespective of an encoder, will have to match
the dimensions of the Oriental gearbox.

It suggests to me that you will have to use Oriental motors and gearboxes, even if they don't have an encoder.

Oriental products are good....but expensive. To replace the motors and gearboxes with Oriental ones is likely to be as or more costly than replacing
the drives so that you could use conventional open loop steppers. You'll still have the gearbox dimensions to contend with.

Craig

[ltpm44]

ok if I have the 2 steppers and drivers ASD24A-A and the steppers fDGM130R-ASAA vexta or the spindle for A and B axis then the Drivers ASD30A-A but missing the Steppers ASM98AA-t7.2 VEXTA plus all the power supply and other equipment what would be the best way to fix this to keep it as good or better then it was operating but also as economical as possible. On this closed loop system.

[joeavaerage]

Hi,
my best guess is that you'd have to replace the steppers with current models of Vexta steppers that have that gearbox fitted in order to have them be a
bolt in fit. They would in all probability not have encoders.

Two possibilities:
1) Fit the stepper and gearbox, sans the encoder and replace the drivers with normal open loop drivers.
2) Fit the stepper and gearbox, but with a dual shaft stepper if available, then supply and fit your own 1000 line encoder and attempt to reuse the drives.

Note that I use 5 phase Vexta steppers and their low lash 10:1 planetary gearbox with Vexta drivers, OPEN LOOP, and I have not lost a step for
five years except if I do something stupid. Closed loop steppers do offer some advantages but not really enough to justify the premium paid.
You could therefore have a perfectly good machine but WITHOUT closed loop X and Y axes.

Craig

[joeavaerage]

Hi,
Oriental?Vexta steppers/gearboxes/drivers come up secondhand on Ebay quite frequently.


OR.....
bolt in two 34 size servos and drives and be done with it!