Spur Gears Part 1: Designing a Spur Gear Connection Based on Known Dimensions

These two Skill Builders are independent of each other. They show typical workflows for the design and calculation of spur gears.

Expected completion time for this Skill Builder is 10 to 15 minutes.

Use it with Autodesk® Inventor® 2008.

Download the Dataset

Spur_Gear_data_set.zip (zip - 1047Kb)

Start the Accelerator

1. Right-click on the assembly panel bar and select Design Accelerator.
2. Click the Spur Gears tool .
   The Spur Gears Component Generator opens on the Design tab. In this exercise, we do not perform the calculation, so you can disable the Calculation tab. Click the Enables/disables calculation command  to disable the Calculation tab.
   Note: Design Accelerator generators open in the last valid state a component was inserted to the Autodesk Inventor assembly.
3. Within the Common area of the Design tab, choose the Center Distance option from the Design Guide menu. We will design the center distance of the spur gears connection based on other known parameters.
   
4. Click the More options command  located in the right lower corner of the Design tab for additional options for spur gears.
5. In the Input Type area, select the Number of Teeth option. In this case, you know the selected parameter is the number of teeth.
   
6. On the Size Type group box, select Module. The Module option is selected if you design spur gears with metric units. If you design spur gears with Imperial units, select Diametral Pitch.
   

Enter Parameters

1. Now, we must enter all available parameters into the Common, Gear 1, and Gear 2 group boxes. We will start entering data to the Common group box. Enter 20 degrees in the Pressure Angle field, or use the menu to select the value.
   
2. Set Helix Angle value to 0.
   
3. Set Module value to 2.
   
4. On the Unit Corrections Guide, choose User so you can enter the unit corrections manually.
   
5. Set Total Unit Correction to 0. The Total unit correction is a sum of unit corrections for gear 1 and gear 2.
   
6. When you design spur gearing, you can insert it as a component or feature, or combination of these. Choose the appropriate options using the drop-down menus in the Gear 1 and Gear 2 group boxes.
   Note: The third option, No Model, is also available. Choose No Model if you want to insert a calculation only without a component or feature.
   

Insert Features

1. In this exercise, we will insert two features. Choose Feature from the drop-down menus in the Gear 1 and Gear 2 group boxes.
   
2. Now, let’s enter the correct number of teeth. Our gear design is based on these known parameters. Enter 19 into the Number of Teeth edit field in the Gear 1 area.
   
3. Enter 29 into the Number of Teeth edit field in the Gear 1 area.
   
4. Set both Facewidth values in Gear 1 and Gear 2 to 22.
   
5. Set Unit Correction in Gear 1 to 0.
   

Place the Gear

1. Now, we will specify the placement for Gear 1. In the Gear 1 group box, click the Cylindrical face button .
2. In the Autodesk Inventor graphics window, select the cylindrical face as shown in the following image.
   
3. Click the Start plane command  to specify the start plane within the assembly.
4. In the Autodesk Inventor graphics window, select the start plane as shown in the following image.
   
   Gear 1 is previewed in the specified position.
   
5. Now, let’s specify the position for the second gear. In the Gear 2 group box, click the Cylindrical face button  .
6. In the Autodesk Inventor graphics window, select the cylindrical face to place the second gear as shown in the following image.
   
7. In the Autodesk Inventor graphics window, select the start plane as shown in the following image.
   
   Gear 2 is previewed in the specified position.
   
8. Click Calculate. The preview is updated and the message within the Summary of messages area informs you that the calculation was performed successfully.
   Note: When you use the Center Distance scenario for your spur gears design, your shafts must have the correct center distance. In this case, it is 48 mm. We already have that set in this exercise. If your Center Distance value in the Common area is different than the actual center distance between the shafts, the calculation indicates design failure and it is not possible to insert the spur gearing into the assembly. You must change the distance of shafts in the graphics window. Return to the Spur Gears Generator and repeat the design.
   
9. Click OK. The File Naming dialog opens. In this dialog you can specify the Display name and File name for Design Accelerator components and features. When the Always prompt for filename box is checked, the dialog box opens every time you insert the Design Accelerator component or feature.
10. Click OK to insert the spur gears connection into the assembly.
    
    

    Save the assembly. This is the end of this Skill Builder. In the next Skill Builder, you will design and calculate spur gears for specified parameters (power, speed, and gears ratio). You will learn how to perform the geometry design, check calculation, and material design.