Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Shaft encoder

Status
Not open for further replies.

justin_t

New Member
Hi

Im looking into an application where a shaft is rotating in a lathe (slowly) and i want to design a controller that will allow the required number of revs to be entered and the controller stops the lathe when they have been completed.

I can do the controller side easily enough but i havent much expereince with shaft encoders. What should i be looking for?

If i have 6 inputs on my controller say, should i be looking for an encoder that produces a 4 or 5 or 6 bit grey code/binary word that i can use in my controller? to compare?

My original simple idea was to have a point on the lathe chuck that a sensor looks for and pulses the controller eac time it passes but this means the lathe has to start with the point under the sensor at the start of the cycle.

Im hoping that with an encoder i can check the parallel input word at start up and increment a counter each time the same code is encountered (each full revolution) meaning the counter can start when any point on the shaft is encountered.

Any ideas? am i making sense?

justn_t
 
hi,
Do you want to count only complete rotations of the lathe chuck.?

If you want to count partial rotations, what resolution do you want.?
 
i only want to count full rotations. but i dint want to have to worry about where i start so if i had say 32 or 64 states (5 or 6 bit) id be happy enough.
Its for twisting steel bars so there is a bit of give in the application.
 
i only want to count full rotations. but i dint want to have to worry about where i start so if i had say 32 or 64 states (5 or 6 bit) id be happy enough.
Its for twisting steel bars so there is a bit of give in the application.

hi justin,
Is it possible to attach a banded/striped strip around the periphery of the lathe shaft.?
If yes it would be easy locate a photodetector to count the white/dark bands passing the detector.
Say 36 bands on the strip,resolution 10deg.

ie: 36 counts/rotatation.
 
Last edited:
Hi justin,

you might use an incremental encoder. They are manufactured with different numbers of pulses per revolution.

Connect to the rear end of the main spindle and you're done.

They require just two input port pins of an MCU.

Check out ALPS for details

Boncuk
 
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top