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Self-Reversing Electric Servo Motor? Answered

Is there a circuit that can change the rotation direction of an electric motor that's cheaply and easily?

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lupinesoul (author)2008-07-25

Pretty much, I want an automatic air pump for my airgun, so I need to make something strong enough to pump a bike pump. If I can pull it off, I'll be able to just hold a button while I reload and it will do the pumping for me.

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bad-bradley (author)lupinesoul2008-10-18

just put a disk on the servo head then attach the pump the the edge of the disk

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lupinesoul (author)bad-bradley2008-11-13

I know, but that would take up too much space... UNLESS! Unless I utilize that disk sticking out of the gun to run a chainsaw bayonet!

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NachoMahma (author)2008-10-18

. Some motors will change direction if you swap the power leads. Others require the windings to be reconfigured. Some can't be changed. If the rotation can be reversed, a DPDT relay will usually handle the job.

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lupinesoul (author)NachoMahma2008-11-13

I know, but I mean instantly, by itself. I got an answer, but thanks anyway! :D

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zachninme (author)2008-10-18

This is exactly what the H-bridge is for!

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zachninme (author)zachninme2008-10-18

You can buy the chips for about $2, or you can make them out of 4 transistors.

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guyfrom7up (author)zachninme2008-10-18

but be careful of inductive kickback

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zachninme (author)guyfrom7up2008-10-18

True. So 4 transistors and 4 diodes...

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