Planetary Gear
Aim: Multibody Dynamic study of Planetary Gears/Epicyclic Gear Trains with the carrier.
Task :
Use the following inputs for designing the Planetary Gear
- Ring Gear
- Module = 2.5 (You must use the metric system in design modeller)
- Number of teeth = 46
- Sun Gear
- Number of teeth = 14
- Input Speed of the Gear = 200 rpm.
- Number of planet gears = 4
With the above input parameters, you are going to run a simulation on the following cases,
| S.No | Input | Output | Fixed |
| 1 | Sun Gear | Carrier | Ring Gear |
| 2 | Ring Gear | Carrier | Sun Gear |
| 3 | Sun Gear | Ring Gear | Carrier |
Parts Required/Components:
1 sun gear
4 planetary gears
1 ring gear
1 carrier
Calculations:
|
Gear |
Module |
Pitch Circle Diameter |
Total no. of teeth |
|
Sun |
2.5 |
X1 |
14 |
|
Planet |
2.5 |
X2 |
X4 |
|
Ring |
2.5 |
X3 |
46 |
we need to calculate X1, X2, X3, X4.
`d= m*t` ( where d= Pitch Circle Diameter , m=module, t=No. of teeth)`
|
Type of gear |
Pitch Diameter |
Module |
No. of teeth |
|
Sun Gear |
35 mm |
2.5 |
14 |
|
Ring Gear |
115 mm |
2.5 |
46 |
|
Planetary Gear |
40 mm |
2.5 |
16 |
Modelling :
To import gears: Go to Design library > Toolbox - ANSI metric > Power transmission > gears > Ring Gear/ Spur Gear.
Carrier Geometry:
Assembling the Parts Together:
Basically, we need two parts in such a way that all parts can rotate and the planet gears can Slide along a plane.
In order to do that we have to fix the DOF (Degrees of Freedom) which are not needed, there are in total 6 Types of Degrees of Freedom –
- 3 Translation Motion (Along X, Y and Z-Axis)
- 3 Rotary Motion (Along X, Y and Z-Axis)
Now as we require only one DOF i.e. Rotation along Y-Axis (Considering that the Sketch is Done on Top Plane) so we need every other DOF to be Fixed. So, for that, we have used Mates (Co-Incident and Distance, Concentric)
Motion Analysis:
Case – 1
Input = 200 RPM
Input Part = Sun Gear
Fixed Part = Ring Gear
Output: Carrier shaft
Animation:
Result:
Angular Velocity Variation with Time in Case 1.
Case 2:
Input = 200 RPM
Input Part = Ring Gear
Fixed Part = Sun Gear
Output: Carrier shaft
Animation:
Result:
Angular Velocity Variation with Time in Case 2.
Case 3:
Input = 200 RPM
Input Part = Sun Gear
Fixed Part = Carrier shaft
Output: Ring Gear
Animation:
Result:
Angular Velocity Variation with Time in Case 3
.
Solidworks File Link:
https://drive.google.com/drive/folders/1B1topapnHicdyRGJOFNPdfI7kCaLp6W-?usp=sharing