Tutorial 1 - How to create an adaptive spring

Tiêu đề: Tutorial 1 - How to create an adaptive spring 22/10/2010, 16:18

If you create and use springs in your assemblies, have you ever wanted to show them compressing and expanding in an animation? Although it may not be at the top of a user’s list of things to learn, it can make for quite an impressive animation,especially now when rendering the output using the Inventor Studio tool available in AIS 10. This tutorial covers one example of the steps required to create and use the adaptive spring.

Step 1

Create a new Part file.
Working within Sketch1, draw a [ shape as shown, making sure that the top and bottom lines are parallel to each other and the other vertical.
Also apply an equal constraint to the top and bottom line. (See Screenshot)
This shape represents the spring radius and height, the top and bottom line represent the centre to radius position for the start of the spring.

Step 2

Now apply 2 dimensions, one for the vertical height, the second representing the radius of the spring.
By highlighting the vertical dimension, make it a driven value by now clicking this icon.
This will allow the value to ‘adapt’ the spring height.
The sketch should now look similar to the following. (See Screenshot)

Step 3

To define the top and bottom of the spring,you’ll need to place a workplane, on to 1st and last line sketch line. To do this, exit Sketch1: using the workplane tool , select the 1st line of the sketch, then by expanding the Origin folder in the browser, select the XZ Plane (assuming the sketch has been drawn in the same orientation as shown). The angle being prompted next should be 0 degrees. (See Screenshot)

Step 4

Now repeat the same process for the 2nd horizontal sketch line, you should now have a workplane based on the top and bottom of you sketch.

Step 5

Place a new Sketch on the initially created workplane, using the Project Geometry tool, project through the end of the sketched line using this projected point, draw a circle at the desired coil cross section diameter, applying a diameter dimension as required. (See Screenshot)

Now finish the sketch.

Step 6

IMPORTANT You must not forget to do this,otherwise the spring will not be able to adapt.

Now make both Sketch1 and Sketch2 adaptive. Simply right mouse click on each sketch and apply the adaptive option.

Step 7

Everything is now in place to create the adaptive spring.

Using the Coil command, the coil cross section will automatically be selected, next defi ne the axis of the spring, this will be the vertical line. (See Screenshot)

The next thing before completing the Coil command, is to specify the Coil Size.

Select the Revolution and Height option in the drop down, the number of revolutions can be anything, as long as it won’t make the coil clash on itself.

Next the height needs to link itself the reference dimension, as specified in Sketch1, this is as simple as when inside the Height type in, just click on the dimension on the screen. (See Screenshot)

Step 8

You’ll now see that you have an adaptive Coil.

To allow easy constraining in an assembly, make Sketch1 visible.

If you want to Flatten the ends of the spring you can at this point either extrude a cut of just use the Split command based on the workplanes at each end of the spring.

Step 9

Save to component, and place into the respective assembly.

Using the visible sketch in the spring, constrain to the centre of the relevant axis.(See Screenshot)

Step 10

Make the spring component adaptive in the assembly.

Now placing a Flush constraint from Workplane1 to the mating face and a Mate constraint from Workplane2 to the other mating face, the spring will adapt to suit the gap.

Finally if you were now to drive the constraint that controls the offset between the 2 components the spring was constrained to (making sure Drive Adaptivity is turned on), the spring will compress and expand accordingly.