Thread: choosing proximity sensors?
Hybrid View
-
29-03-2019 #1
Hello all.
I'm in the process of choosing proximity and homing switches. I have noticed that there are different sensing distance switches from 1 to 4 mm are there any benefits in choosing switches with a 1mm sensing distance (are they going to be more accurate for homing?) Any other information gratefuly accepted ie npn or pnp.
Cheers Andrew
-
29-03-2019 #2
Hi waldo,
I spend only €13,- on 5 units... m8 6-36 vdc 2mm sensing distance.
Aliexpress
lj8a3-2-z/bx npn
Just a single meter of wire on the sensor.
I use a sloped metal surface of about 20 deg for sensing.
I am very impressed by the accuracy.
homing is spot on on a cheap 0.01 mm tdi every time.
They switch to negative / ground on contact.Almost no resistance compared to grond.
In the off position they have about 10k series resistor in the switching wire
Had to do some tinkerring with resistors to interface with the cheap 5 axis Bob i have.
Not sure what your budget is for them or what controller electronics you have.
Grtz Bert.
Verstuurd vanaf mijn SM-A320FL met Tapatalk
Last edited by driftspin; 29-03-2019 at 06:46 PM.
-
The Following User Says Thank You to driftspin For This Useful Post:
-
30-03-2019 #3
With proximity sensors you could use two switches in series, one sensing axis position directly and the second sensing a cam on the rotating screw - instant multiplication of homing resolution ;-)
You think that's too expensive? You're not a Model Engineer are you? :D
-
30-03-2019 #4
-
31-03-2019 #5
I'll be using it on my Chester mill conversion, I've decided to get my new VMC up and running first and make the rest of the parts for the conversion with the big CNC.
You think that's too expensive? You're not a Model Engineer are you? :D
-
31-03-2019 #6
-
31-03-2019 #7
Anything with a high point that a proximity switch can sense at a repeatable point in the homing direction will do, you could use a single bladed chopper too, anything which sticks out significantly more at one point in it's rotation will do.
Mount the cam near one end of the screw and mount the proximity switch so that it is triggered by the cam.
Simples! ;-)
Here's a pic I found, imagine a gear with just one tooth.
You think that's too expensive? You're not a Model Engineer are you? :D
-
The Following 2 Users Say Thank You to magicniner For This Useful Post:
-
01-04-2019 #8
-
01-04-2019 #9
Thread Information
Users Browsing this Thread
There are currently 1 users browsing this thread. (0 members and 1 guests)
Similar Threads
-
Help with setting up proximity sensors and Mach 3
By Wooddesign in forum Gantry/Router Machines & BuildingReplies: 0Last Post: 10-03-2019, 09:27 PM -
Homing with proximity sensors
By routerdriver in forum General ElectronicsReplies: 4Last Post: 19-12-2017, 06:32 PM -
Help with proximity sensors
By D-man in forum General ElectronicsReplies: 18Last Post: 14-04-2016, 11:36 PM -
FOR SALE: Inductive proximity sensors
By Web Goblin in forum Items For SaleReplies: 0Last Post: 26-01-2016, 06:05 PM -
FOR SALE: Proximity sensors
By Web Goblin in forum Items For SaleReplies: 5Last Post: 13-09-2014, 08:02 AM
Bookmarks