One way rotation into oscillating rotation, how can I do this?

[Jarfi]

I know very little about mechanical systems, but what kind of small simple gear system can do this;

I have a motor, it turns one way, I guess it would turn a spiral bevel, but it only goes into one direction since the motor turns continuously in one direction, what mechanical solution allows me to turn this one way spin into another spiral bevel or any gear whatsovere that turns back an fourth? oscillating from turning clock wise and then anti clockwise, with a frequency depending on the motor speed, and range in degrees(how much it turns clock and anti clockwise from starting point)

What is a method to do this? the smaller/simpler the better.

 

[Baluncore]

The chosen method would depend on the angle you want the output to oscillate through. Is that angle more than 120°?
Windscreen wipers use a worm driving a wheel, the wheel has a crank that drives the wiper arm.

How many motor turns per full oscillation cycle of the output?

 

[Jarfi]

The chosen method would depend on the angle you want the output to oscillate through. Is that angle more than 120°?
Windscreen wipers use a worm driving a wheel, the wheel has a crank that drives the wiper arm.

How many motor turns per full oscillation cycle of the output?

I think the angles domain would be around [-45;45], can be a smaller angle and I probably won't need a much larger angle.

I googled some cranks and it seems like there are several solutions, a crank seems like the simplest most obvious one.

 

[DrBwts]

A 4 bar linkage would be the easiest method