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Need help with rotating electrical connection!

Hey guys,

 

I'm doing a project and would appreciate some help. I essentially have a DC motor controlling a blade from the center. On the blade is a sensor that I need to wire to the main circuit that is below the DC motor. The problem is when the blade rotates the wires will obviously tangle.

I know slip rings may work but I hear they are generally expensive and very noisy. I have read on some things like using audio jacks with maybe some coaxial cable. The sensor has 4 connecting wires, and whatever the rotating mechanism is, won't be able to be placed at the center because that's where the motor is, or am I wrong?

 I'd really appreciate if anyone could help me. Thanks :)

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if you can find an coaxial audio jack with four contacts, you can run the signal wires up and over the motor, connecting from the top.

How would I go about this?

Do I connect the 4 wires to where the male part would be and then run that down to the main circuit where a fixed female jack would be? I'm just trying to visualize this.

Also do you know how many wires are inside a coaxial audio cable? If theres less than 4 would it be possible to use 2 of these cables?

Thanks for the help!

IMG_4813.JPG?imgmax=512 Frits pulled it off here. With video!

what speed is the blade doing? (Revolutions per min)

It's actually not going to be spinning much, i only want it so if it needs to spin it can, without having to worry about wires. Essentially, I don't see the speed ever going past about 10-20 RPM.

You could try ball bearings like this guy:

 

http://www.maybevideodoes.de/howto/slipring.html

 

 I haven't tried it myself but it looks promising.

 

There is a swivel connector that you connect to your phone handset to stop the cable from winding up. They are cheap, and and have four connections I believe. Should work well for low rpm applications.