STEP 1: Add a closed sketch-chain (sketch-loop) to represent the Path of the Belt

a)Edit the Base-Part

b)Part-Editor: Add a sketch-loop with more than two Arcs

c)Part-Editor: You MUST add a dimension to each Arc. The exact radius of the Arc is not important.

The Belt will be Driven by a Driving-Pulley, which will be a Rocker

d)Part-Editor: Add a Line - its start-Point is merged or coincident with the center-point of an Arc.

e)Close the Part-Editor

STEP 2: Add Motion-Path FB  

Select the sketch-loop that represents the path of the belt.

The Motion-Point shows at the start-Point of the sketch-element you select in the sketch-loop.

STEP 3: Add a Rotating-Part for each Pulley.

Add one rotating-Part with its Pin-Joint at the centre of each Pulley.

The length of each Part is not important.

STEP 9: Add a Motion-Dimension FB to the Part you wish to be the Driving-Pulley.

A maximum of one kinematically-defined Part can be a Driving-Pulley.

Add menu > Mechanism sub-menu > Add Pulley

Machine-elements toolbar > Add Pulley

The Add Pulley dialog starts in the Command-Manager.

Do Add Pulley to the kinematically-defined Part first.

Click, in the graphic-area, from top to bottom.

1.The Pin-Joint

2.The Motion-Path FB

The Part-Editor opens with sketch-path to which you add the Motion-Path FB

3.The radius Dimension of the Arc

The Part-Editor closes

4.The Part joined with a Pin-Joint at the center of the Arc.

5.Click  in the Command-Manager.

The Pulley should now be in the model.

Do Add Pulley × five(5) to add a total of five Pulleys.

Notes: Default colors of the Pulleys:

Driving-Pulleys are Lilac

Driven-Pulley are Magenta

Edit the Number-of-Teeth on a Pulley.

1.Open the Pulley dialog-box

Double-click a Pulley in the graphic-area

- or -

See How to open a dialog-box

In the Pulley dialog-box

2.Edit the Number-of-Teeth

Repeat 1 and 2 for each Pulley.

3.Edit the Motion-Dimension FB to 0º .

When the Driving-Pulley is at 0º, the other Pulleys will also be at 0º.

Belts have an integer number-of-teeth. Also, belt manufacturers have preferred lengths of belts. We use the Motion-Path dialog-box to enter a Target Path Length

The Target Belt Length tool moves a Pulley, or a controlling-dimension, to edit the length of the belt.

Thus, we need a dimension in the sketch-path that will change the length of the belt. We will edit the length of the Belt to a length that is exactly divisible by Tooth-Pitch to give an integer number of teeth on the Belt.

In the design to the left, we will make the Tensioning Pulley the pulley at the top the sketch-path.

Therefore, we will select this dimension highlighted in RED. (102.2)

This dimension is called the Controlling Dimension.

The Motion-Path dialog-box will change the Controlling-Dimension as we edit the Target Path Length

STEP 1: Edit the Motion Path FB to edit the Length of the Belt.

1.Double-click the Motion-Path FB  to open its dialog-box dialog box (or see How to open a dialog-box)

2.Motion-Path dialog-box > Length Control tab > Control-Length of Path  > Belt Tooth Pitch =10 (mm)

You will see the Actual Path Length is not equal to Tooth-Pitch × Integer Number-of-teeth

3.Click the Controlling Dimension box

The Part-Editor opens to edit the Part in which the belt is defined by the sketch-path.

4.Click the dimension you want to use to change the length Belt - see above

The Part-Editor closes

The dimension value shows in the Controlling Dimension box

The default Target Path Length = Actual Path Length

The Maximum and Minimum Dimension Values are Soft-Limits to the Controlling-Dimension.

You can edit the Maximum and Minimum Values if you need to edit the Controlling Dimension by more.

6.Edit the Target Path Length SLOWLY with the Spin-Box tool to increase or decrease the Actual Belt Length.

If the Actual Path Length does not change, you probably to Increase the Control-Dimension Min

Then edit Target Path Length again.

If needed, you can select a different dimension to adjust.

1.Click the Clear Controlling Dimension button, immediately below Path Length using Dimension