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Electronics => Electronics => Topic started by: anh_risn on May 17, 2011, 08:44:41 PM

Title: Disc slotted rotary encoder
Post by: anh_risn on May 17, 2011, 08:44:41 PM

Hi there,

Can anyone tell me where I can get disc slotted rotary encoder? I just searched on the net but still didn't find yet.
I just need to buy this slotted disc rotary encoder, and put it together with the phototransistor to read motor data.

Also, I am planning to put rotary encoder, I found from Hengstler RI58-D encoder
http://www.hengstler.com/gfx/file/shop/encoder/encoder_iiih_ri_58-d_en.pdf (http://www.hengstler.com/gfx/file/shop/encoder/encoder_iiih_ri_58-d_en.pdf)
Can I use as a wheel position sensor? The wheel rotate slowly but I need accurate data.
Also, the encoder has several type output, RS-422 and push-pull, it also has channel A, B, N.
What it's mean? Can anyone please help me?

Thanks,

Title: Re: Disc slotted rotary encoder
Post by: kl22 on May 18, 2011, 03:34:57 AM

Not sure but maybe this is the product you are looking for:

http://www.robotshop.com/ca/cytron-simple-rotary-encoder-kit.html (http://www.robotshop.com/ca/cytron-simple-rotary-encoder-kit.html) (Canadian)
http://www.robotshop.com/cytron-simple-rotary-encoder-kit.html (http://www.robotshop.com/cytron-simple-rotary-encoder-kit.html)

Title: Re: Disc slotted rotary encoder
Post by: waltr on May 18, 2011, 07:22:26 AM

Older PC Mice used a slotted disc and photo-interrupter. You may be able to salvage the parts for your needs.

Title: Re: Disc slotted rotary encoder
Post by: blackbeard on May 19, 2011, 04:11:07 AM

Quote from: waltr on May 18, 2011, 07:22:26 AM

Older PC Mice used a slotted disc and photo-interrupter. You may be able to salvage the parts for your needs.

the problem with that is that he would need to do allot of modification to make sure that he can attach the wheel to his drive system. a hot glue gun is recommended! if the speed is relatively fast i might recommend that a free method might be to use a hard drive motor. they make very good encoders as i have tested but only at higher speeds

Using Hard Drive Motor to Make Pretty LEDs Blink (aka rotory encoder with an op amp) (http://www.youtube.com/watch?v=ajmDEWDWzzM#ws)

Title: Re: Disc slotted rotary encoder
Post by: Soeren on May 20, 2011, 05:46:51 PM

Hi,

Quote from: anh_risn on May 17, 2011, 08:44:41 PM

Can anyone tell me where I can get disc slotted rotary encoder? I just searched on the net but still didn't find yet.

There is a number of encoder printing programs (and at least one.eps file for the sam purpose) floating around the net.
If you print one of these and glue it to a thin piece of aluminum plate, you can cut it out yourself.

You might be able to position the IR TX/RX well enough to use a coarse gear wheel as well.

If you take a stepper motor or a synchronous (mains) motor apart you should find a "comb wheel" that can be used either with IR or with a Hall sensor.

How many segments/holes do you need?