Suggetions on supplying the power to the rotating parts

Other Hardware Motors, Mechanics, Power and CNC
1

Hi all,

I am thinking of developing a Persistence of Vision Display. Hope you are familiar on that. No worries this article will quickly say you what..

http://people.ece.cornell.edu/land/courses/ece4760/FinalProjects/s2012/jm787_dab355/jm787_dab355/index.html

There are many types of displays that looks like a wheel or cylinder but the basic thing is you need to rotate the lights. And of course you need power to the lights :slight_smile:

So there are several approaches to provide power to the lights. Either you can include a battery in rotary part or you can use a set of "brushes" to supply the power to arduino. If you need to light them continuously the battery option is not feasible.

My question is how do you implement these brushes? I've once used a 3.5mm earphone jack and a socket to implement such requirement (Of course it won't work in this case). And yes I can use a barrel like conductor (I used a outer barrel of AV socket) on motor shaft with a copper brush as one terminal and the shaft of the motor as the other terminal. But doing these things practically is not much easy.

So I would like to hear about easier practical ideas. Is there some component that I can buy (say on ebay) to implement this requirement?

/Chathuranga

2

adafruit sells some slip ring assemblies.

One time I used a good quality metal 1/4" stereo jack and plug assembly for a 3 circuit rotating slip ring.

Lefty

3

I suggest you search ebay for "slip ring".

4

I used some brass tube, the sort you get from hobby shops. I soldered wires on the inside and lead them out of the supporting rod through a slot. Then I arranged phosphor bronze leaf springs to make contact. It worked well.

5

dc42:
I suggest you search ebay for "slip ring".

Surprisingly EBay does not have much listings. I can only see several hits and they are not the slip rings with a bore inside. So using it with a motor is bit more complicated because I need to add a pulley and a belt for the motor.

6

Grumpy_Mike:
I used some brass tube, the sort you get from hobby shops. I soldered wires on the inside and lead them out of the supporting rod through a slot. Then I arranged phosphor bronze leaf springs to make contact. It worked well.

Thanks for info Mike, Can you please shed some light about "phosphor bronze leaf springs"? Is it something that does not lose it's tension after many revolutions?

7

chathuranga:

dc42:
I suggest you search ebay for "slip ring".

Surprisingly EBay does not have much listings. I can only see several hits and they are not the slip rings with a bore inside. So using it with a motor is bit more complicated because I need to add a pulley and a belt for the motor.

Here is an example: http://www.ebay.co.uk/itm/Mini-Capsule-Slip-Ring-6-Wires-2A-22mm-300Rpm-360-Degree-Rotation-/221200967555?pt=UK_BOI_Electrical_Test_Measurement_Equipment_ET&hash=item33809ae783.

What do you mean "with a bore inside"? You didn't mention that in your initial post.