How to Draw an Induction Coil Symbol with Adobe Illustrator

Induction coils are one of the most frequently used components in electronics. If you are documenting any electronics equipment or system, you may have to draw an induction coil symbol at some point. Here is how to do it.

1) Draw a circle.

2) Pick the Selection Tool (V). Press the Alt button (Windows) and drag the circle to duplicate it.  HINT: Your cursor should transform into a Double Overlapping Arrow.

3) Drag and create 4 similar identical circles. Make sure they are tangent to one another:

4) Select Direct Selection Tool (A). Click on all the circles to display their anchor points. Click on the bottom-right quadrant of a circle to select it.

5) Press Delete to delete the bottom-right quadrant. Repeat the same for all the bottom quadrants until you end up with the following image:

NOTE: click the Direct Selection (A) tool anywhere outside the image in between selecting the quadrants in order not to delete the whole circle by mistake.
6) Select the Pen Tool (P) and add two connecting lines to the ends of the figure and you’ve got your induction symbol:

NOTE: Group the sections (Ctrl + G)  to preserve the integrity of the image.
Another variation is to overlap the circles and then deleting the non-needed segment to create the following induction symbol:

 HINT: When overlapping the circles to create the above symbol, it helps if you select the whole image and then select the DIVIDE option from the Pathfinder tab:

The DIVIDE command breaks apart every single segment in the overlapping circles and makes it much easier to pick and delete individual segments with the Direct Selection (A) tool.
Other variations easily created from the above symbol by using the Pen Tool (P): 
IRON CORE Inductor:
:
FERRITE CORE Inductor:

VARIABLE Inductor: