Tightening Your Designs with the Belt Generator (Avatech Tricks Tutorial)

30 Apr, 2009 By: Anthony Dull

This easy-to-use tool in Autodesk Inventor is sure to become one of your favorites as you complete your digital prototype.

Editor's note: This tutorial courtesy of Avatech Solutions.

Design Accelerators are found within an Assembly file on the Panel Bar.

Autodesk provides many Design Accelerators within Inventor such as, Bolted Connection, Shaft, O-Ring, and Spring to name just a few. Today, I want to focus on just one, the Belt Generator. Anyone who has manually created a belt assembly and all of its components and constrained them together will truly appreciate how valuable this generator is. As with any other feature or task in Inventor, at any time you can go back and modify/update your belt design very easily. That functionality is always just a right-click away.

The Design Accelerators are found within an Assembly file (.iam) on the Panel Bar -- click the down arrow and select Design Accelerator. All three Belt Generators act in the same way, so for this tutorial we're going to work with the Synchronous Belt option.

Picks and Clicks

The Inventor dialog box typically works from the top-left to the bottom-right. So within the Belt section first choose the type of belt that you want to use.

First choose the type of belt that you want to use.

On a side note, if your company uses different belt sizes then the ones provided, you will need to create a custom belt.xml file and import that file. Then select the surface or work plane that will act as your belt's midplane.

Next, within the Pulleys section, add the required number of pulleys by selecting Click to add pulley. Then, as necessary, change the type of pulley by selecting the down arrow next to each pulley. You can further define your pulley's properties by clicking the button with the "Three Dots" next to the drop down arrow. The button with the "Red X" will delete the pulley. The options for how the pulley is going to be represented are Component, Existing, and Virtual. You should also define how the pulley is going to be positioned, whether it is going to be fixed, sliding, and so on. Lastly, we need to specify where in the assembly our belt is going to reside by using the Select Geometry button to locate the pulleys.

Specify where in the assembly the belt is going to reside.

The Calculations tab allows you to further refine your design by specifying loads and properties. As you enter the required inputs, periodically click the Calculate button at the bottom of the tab. This will verify that your design is within or out of design compliance. If your geometry and or options within the dialog turn red, this indicates that your design is out of design compliance and requires further modifications. Make sure you always select Calculate after making changes to validate your revised design.

Select Calculate after making changes to validate your revised design.

Drive Me constraints.

Driving the Belt Assembly
Finally, with the belt fully defined and placed in the assembly it is time to make it move. In the browser, right click on the newly created belt assembly and check Flexible. The pulleys will now be able to spin in conjunction with one another. Add an angle constraint from one of the pulleys to a fixed plane or surface then, drive the constraint to have the pulleys spin a set number of times. Do not forget to rename your driven constraint to Drive Me so, when you go back to drive it again in the future, the constraint is easily recognizable.

One thing to point out here is that this will not work if you have your belt displayed as Detailed. At this time, the belt must be either displayed as Solid or Sketch for the pulleys to spin. Utilize other Design Accelerators and part features to finish off your design.

Display belts as Solid or Sketch for the pulleys to spin.

The Belt Generators is just one of the many productivity enhancements that Autodesk provides. This easy-to-use tool is sure to become one of your favorites as you complete your digital prototype.