# how to make/coil a motor for linear motion?

well i want to use emf in such a that instead of producing torque as in most of the motors i will produce linear movement of coil.

i know how to change rotatory motion in linear with gears so don't ask me to use gears

a diagram or link to a instructable would be nice

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3 years ago
The motion of a speaker coil is linear.  In a speaker, I and B are at right angles to one another, and the motion of the speaker cone is at right angles to both I and B.

I found a picture of this here:
http://www.physics.sjsu.edu/becker/physics51/mag_field.htm

There's a  whole plethora of pictures on that page.  The speaker coil arrangement is Figure 27.28, so you'll have to scroll down a bit for it.

That page also has some other arrangements of magnets and wires that might be of interest to you.  The "Linear Motor" of Figure 27.63, or the "Electromagnetic Pump of  Figure 27.75, might be what you are looking for.

Also if you are sort of looking for ideas you can identify by picture, a Google Image search works well for this, e.g.
I mean I have seen that picture of the "Linear Motor" before in textbooks, and I was trying to find another version of it to show you, hence the Google Image search.  But there were some other pictures that looked interesting too, so you might take a look at that, and see if any of those are what you are looking for.
3 years ago
AKA "Voice Coil Actuator" - there is an EXTREMELY detailed Instructable on the design and construction of a VCA.
3 years ago
3 years ago
That's the one ;-)
UtkarshT51 year ago

Were you able to get this done? I'd highly appreciate if you could share some details on this.

iceng3 years ago
Use two or more coils
Glue flat magnets N-S-N-S- in a line
Switch some current sequentially in the coils
Observe resulting linear motion due to EMF.

A
3 years ago
Some examples of linear motors are the latest roller coaster emf accelerator using coils
The watt-meter which induces an eddy current in an Al plate and attracts or repels it,
You only need to have a plate that is a straight track to run a train on.

After all EMF means Electro Magnetic Force
ie electric current in a wire makes a magnetic field that exerts a force on its surroundings
As any compass will be able to discern for you.

Engineers have been using coil generated EMF in clever ways to make ( Mag-Lev ) trains for time before you exited.
These are machines without gears that move in a linear direction using
EMF generated by coils of wire.
3 years ago
I met the man who invented linear induction motors, the great Professor Eric Laithwaite, gone these last 16 years.
3 years ago
A good man, pilot and Engineer, ahead of his time,
following a passionat interest in non-rotary electric machines
But, we are still only diddling with personal electrical propulsion.

BTW I meant existed not exited in above blurb....
3 years ago
I'd swear Laithwaite could see magnetic fields.
3 years ago
I had a very good friend, Jack Greenwell a smoker now passed, who could see flux :-)

An example of his genius is what I still use today to clean out a stator
for rewinding.   Disassemble a rotary  induction motor and place only the
stator shell in a wood fireplace overnight.  The next day a diagonal cutter,
a simple pair of needle nose pliers easily pulls the windings varnish topsticks and
slot insulation with only a brush to clean the well annealed laminations.
Ready for a better set of windings.

rickharris3 years ago
It would help a lot if you told us what your trying to do with it.
Kiteman3 years ago
Make a solenoid, and have a loose iron rod partly inside - switch on the current, and it will pull the rod further into the coil.
Atul009 (author)  Kiteman3 years ago
thats a coil gun and i. wont be able to move it backward maybe i can by replace iron with magnet but leave that
i want to utilize electromotiveforce
not attraction force
3 years ago
It's a doorbell as well.

If you want it to push, you have a non-magnetic rod on the end: as the iron core is pulled in, the non-magnetic part is pushed out.
3 years ago
A coil gun is merely a type of solenoid.
3 years ago
2 coils and a longer iron rod, alternating voltage between coils using a 555 timer?
Josehf Murchison3 years ago
Google or search “Coil Gun” and you will get hundreds of web pages.

The theory is simple, the ferrous projectile follows the magnetic field through the center of the coil.

Magnetic field in blue arrows positive in red arrow negative black arrow indicating current flow.
steveastrouk3 years ago
Like a solenoid ?