Variable Pitch Conical Spring Pro/ENGINEER Wildfire 2.0

CREATE A SPRING USING HELICAL SWEEP Create a Protrusion using Helical Sweep options.. From Insert pull down menu, select Helical Sweep -> Protrusion Done Pick FRONT datum plane as the

ME-430 INTRODUCTION TO COMPUTER AIDED DESIGN

Variable Pitch Conical Spring

Pro/ENGINEER Wildfire 2.0

Dr Herli Surjanhata START CREATING A NEW PART

Create a part named con_spring and begin with three default datum planes It is not

necessary to change the Units since inches is the Pro/ENGINEER default units

CREATE A SPRING USING HELICAL SWEEP

Create a Protrusion using Helical Sweep options

Click the

Create new object icon

From Insert pull down menu, select

Helical Sweep -> Protrusion

Done

Pick FRONT datum plane as the sketching plane, and TOP as the Top reference Select Top

and Right as Specify Refs planes

Begin with sketching a vertical centerline along RIGHT using the icon

Select icon to sketch an inclined line as shown below

Click to dimension the sketch as shown below Make sure the bottom point of the inclined line has diametrical dimension with respect to the center line

Click icon to modify the dimensions

Note that start point of the line is on TOP/DTM2, and inclined to the left Re-dimension and modify the dimension of the profile as shown above

To obtain diametrical dimension 7.5”, do the following:

Left-click end point of line at the bottom -> left-click center line -> Left-click end point of line at the bottom again -> middle-click to accept the position of the dimension

Click this icon to continue

Enter [1] for the pitch

Sketch a circle with diameter 0.5 centered on the centerlines

Click the icon to continue

Preview the defined elements and choose OK from the dialog box to com-plete the helical sweep feature

The finished part in standard orientation view should appear

as shown below

Click the icon to save the spring

OK

Right click the helical sweep protrusion in the model tree, then select Edit

Pick the trajectory inclined line

Right click, and select Edit

Pick PITCH1.00 and change the value of the pitch to [1.5]

Select the to Regenerate to see the effect

MODIFY THE SPRING – VARIABLE PITCH

To change the pitch at specific locations along the sweep, right click the Protrusion in the model tree, and select Edit Definition

Pick the Attributes first, then press and hold Ctrl-key, pick Swp Profile and Pitch elements followed

by click Define

Choose Variable and Done from the ATTRIBUTES

menu

Now Modify -> Done from the SECTIONS menu Select Sketch from SECTION menu Click Sketch

from SKETCHER

Use the Point icon to add three sketcher points as shown in Figure Dimension the points as shown

Click the icon to continue

When you are done with the section enter

[0.75] as the pitch at the start and end of the profile

A PITCH GRAPH will appear in a sub-window

Pick the three points in the main window, select the lower point first, and the system will prompt for the pitch at each added point and move up to the next point until all points are added Pitch at those points as shown below The graph will automatically update

Choose Done from the GRAPH

menu and OK from the dialog box

CREATE A REVOLVED PROTRUSION AT THE BOTTOM PART OF SPRING

Click the Revolve Tool icon

Select this surface

as Sketch Plane

Click the Revolve

Tool icon

Pick the white are of Reference option to activate it

For the Reference of Sketch Orientation, pick the TOP datum plane

Pick the Sketch button

Pick TOP and RIGHT datum planes as references

Click the Close button

Pick the Create an entity from an edge icon Select Single option

Pick the top and bottom edges of wire Draw a centerline as axis of revolution

Click the icon to continue

Change the revolved angle to be 180 and click the button to finish

CREATE A REVOLVED PROTRUSION AT THE TOP PART OF SPRING

Repeat the same procedure as shown above for 180° revolved protrusion, here below is some useful information

Use edge of the wire for the section to be revolved

Draw a centerline as axis of revolution

Select this surface

as Sketch Plane

Note that A_2 is the axis created during revolved protrusion at the bottom part of the spring

Click the icon to continue

Change the revolved angle to be 180 and click the button to finish

CREATE A CUT FOR GROUND SPRING

Click the Extrude Tool icon

Pick the FRONT datum plane, and select the

Sketch button

Click the Extrude Tool icon

Draw a rectangle as shown

on the figure, and make sure the height dimension is 10 inches

Click the icon to continue

Click the Remove Material icon

Click the Change material direction icon

Select the Extrude on both sides icon, and enter the depth 10 inches

Click the button to complete the both sides cut

The resulted spring is shown below