Some basic DC motor kit questions

[Tinker Tantrum]

Hello All,

I am building a basic motor kit for my brother and wanted to teach him about motors along the way. But I'm having trouble answering some of his questions such as:

1. Why must the coil in a motor kit be wound in only one direction?
2. Why does the current have to change direction every 180 degrees in the motor?

Any technical answer or advice on where to get the answer would be most appreciated.

Thanks in advance...

 

[bob]

Check here http://www.google.com/search?source...S493US493&q=Some+basic+DC+motor+kit+questions

 

[G._S._Ohm]

Hello All,

I am building a basic motor kit for my brother and wanted to teach him about motors along the way. But I'm having trouble answering some of his questions such as:

1. Why must the coil in a motor kit be wound in only one direction?
2. Why does the current have to change direction every 180 degrees in the motor?

Any technical answer or advice on where to get the answer would be most appreciated.

Thanks in advance...

It's been a while, but. . .

if you wind the coil in two directions some of the current flow in that coil cancels out

because when you reach 180 deg. with a two segment commutator the rotating force (MMF) reaches zero (?)

Don't take my word for it. Try it.