Position signals

[Hood]

It needed the word "reflective" in the search term! 5mm range.

Will take a look at that and see if my brain understands it

In the meantime I also found this but not really sure if it could be used for what I want as data sheets confuse me more than enlighten
https://uk.rs-online.com/web/p/slotted-optical-switches/1742530/

 

[ajlelectronics]

Description of use here:

https://www.adafruit.com/product/2349

Nicely compact, robust and easy to interface. Slot in the housing makes it dead easy to mount physically.

 

[Hood]

If the belt snaps the switch does not move. It has positive detents so will still signal the position it's at.

Yes, that is true, could well be a contender.

 

[Hood]

Description of use here:

https://www.adafruit.com/product/2349

Ahhhhhh so basically it is like a slotted opto except it does it all from the end, yes I could see that working well if the dimensions are ok

 

[Seadog]

Yes, that is true, could well be a contender.

One drawback, operational life. Only 10,000 operations

 

[ajlelectronics]

Ahhhhhh so basically it is like a slotted opto except it does it all from the end, yes I could see that working well if the dimensions are ok

Yes, exactly the same as a slotted opto switch, but you don't need a probe attached to the turret. A white dot will do the job and there is nothing to get caught up and broken. You already know about opto switches, so should be a doddle for you.

 

[Hood]

One drawback, operational life. Only 10,000 operations

Sounds a lot but really in the scheme of things it is not.

 

[Hood]

Yes, exactly the same as a slotted opto switch, but you don't need a probe attached to the turret. A white dot will do the job and there is nothing to get caught up and broken. You already know about opto switches, so should be a doddle for you.

Ah now that last bit is not quite true, it should be that I have used optos, I certainly don't know a lot about them

 

[Hood]

@ajlelectronics
Do you have a link to where they can be had?
Looked visa the part number and get all sorts of weird hits.

On RS I am only finding this kind so far, which are far too big. I actualy have some of them already and never really knew what they were as they were just in a box of usefull stuff I acquired

 

[Hood]

Just searched the box but sadly only these kinds, at least I know what they are now

 

[ajlelectronics]

https://cpc.farnell.com/optek-techn...6Eg_f7_KEomNkMbk0JAJi53iEs3ANi_8aAgfYEALw_wcB

 

[Hood]

https://cpc.farnell.com/optek-techn...6Eg_f7_KEomNkMbk0JAJi53iEs3ANi_8aAgfYEALw_wcB

Thanks

 

[Fazerruss]

Look for a "photo interupter" widely used in photocopiers, laser printers. Used with a simple disk that has cut outs rotating through it. This gives a change in state either + or - depending on the polarity.

 

[Hood]

Look for a "photo interupter" widely used in photocopiers, laser printers. Used with a simple disk that has cut outs rotating through it. This gives a change in state either + or - depending on the polarity.

Oh man you have just caused me some work, I have an old HP laser printer here that I was going to be throwing out, looks like I will have to break out the surgical tools, or BFH as I usually call it to see if there is anything inside it.

 

[Hood]

Looks like a photo interrupter is very similar to a slotted opto, the reflective one linked by @ajlelectronics will suit me better I think.

Found a load of these things in a bag of junk and they seem to be light sensors of some sort, certainly the resistance changes greatly with the amount of light they receive but I have no info on them and even if I did it would likely be a lot more hassle to get them doing what I want, especially when the reflective sensors are so cheap.

 

[Seadog]

They're photocells. They could be used but probably not worth the fiddling about.

 

[ajlelectronics]

That is a CDS photoresistor. Resistance varies with the amount of light falling on it.

 

[Hood]

Just looking at the model I did when designing the turret and I think I can probably fit the reflective sensors inside the housing and make up a disc from black delrin with white inserts and fit that to the main sliding coupling. That would mean everything is enclosed and it is reading from the final stage of the drive so no broken belts or couplings would interfere with the readings. Pic below of the cutaway of where they should fit.
Best bit is it is only 4 cap screws and the whole housing/gearbox/motor etc comes off so access is easy

 

[eSCHEn]

That looks like a good old ORP12 sans plastic case. Blast from the past there!

 

[Hood]

That looks like a good old ORP12 sans plastic case. Blast from the past there!

Want some? could pretend you are back in the good old days