# TUTORIAL: Disc Coil Spring using Curve from Equation in Pro/ENGINEER

**TUTORIAL: Disc Coil Spring using Curve from Equation in Pro/ENGINEER**

*Version: Pro/E 2001, Wildfire, Wildfire2.0, Wildfire3.0, wildfire4.0*

Datum Curve from Equation tool is to be used when you want to create a disc coil spring / planar spring in Pro/ENGINEER. We are going to create a datum curve from equation as the trajectory and then apply a sweep thru the spiral curve.

1. Create a new Solid Part file. From the tools icon, click the create datum curve icon .

2. In the pops-up menu manager, choose From Equation and Done to proceed.

3. The Curve: From Equation dialog box appears and you are requested to select a coordinate system (CSYS). Select a Csys from the display.

4. You will need to define the Csys Type. For this tutorial, choose Cylindrical in the menu manager and proceed to the next step.

5. Next, a Notepad window appears for you to input the Equation. You can write any mathematical equation to model the desire curve. For a spiral curve sit on a planar, the following equation is being use

R = 50 + t * (120)

Theta = t * 360 * 5

Z = 0

6. You can substitute the values accordingly to design your own disc coil spring. The figure below may help you to understand the equation better.

7. When you are done, click OK on the Curve: From Equation dialog box to confirm. The spiral curve should appear in your display by now.

After all, you can use the sweep feature to complete the disc coil spring.

You can download the completed Disc Coil Spring by clicking here.