Planetary Gear

Aim: To perform the Motion analysis of the Planetary Gear system.

Description:

Gears: Gears are used to transmit motion from one shaft to another or between a shaft and a slide. This is accomplished by successively engaging teeth.

PLANETARY OR EPICYCLIC GEAR TRAIN

• A gear train having a relative motion of axes is called a planetary or an epicyclic gear train (or simply epicyclic gear or train). In an epicyclic train, the axis of at least one of the gears also moves relative to the frame.
• The epicyclic gear trains are useful for transmitting high velocity ratios with gears of moderate size in a comparatively lesser space. The epicyclic gear trains are used in the back gear of lathe, differential gears of the automobiles, hoists, pulley blocks, wrist watches etc.

Objective:

• With the above input parameters, to run simulations on the following cases,

Sl. No	Input	Output	Fixed
1	Sun Gear	Carrier	Ring Gear
2	Ring Gear	Carrier	Sun Gear
3	Sun Gear	Ring Gear	Carrier

• To plot the angular velocity of the output.

Figure: Flow of the project.

3D CAD models

Carrier

Planetary gear chain

Steps followed:

• 3D models are created using the design library in SolidWorks.
• Different gears are assembled on the basis of the given information.
• 3D model of the carrier is created according to the dimensions of the gears
• A motor is installed at the input with given rpm and the different gears are fixed according to the cases.
• Contacts are established between the gears as per our requirement.
• After running the motion analysis, the required plots are plotted.

CALCULATIONS

• Module for all the gear: 2.5
• Ring gear: Teeth: 46,
• Diameter: 46x2.5 = 115 mm
• Sun gear: Teeth: 14,
• Diameter: 14x2.5 = 35 mm

Planetary gear: (4)

• Diameter of planetary gear: (Radius of ring gear) - (Radius of Sun gear)
• Diameter of planetary gear:`115/2-35/2`
• Diameter of planetary gear: 40 mm
• D = MxT
• T = 16 teeth
• Face width = 10 mm

Results:

CASE 1

Input	Output	Fixed
Sun Gear	Carrier	Ring Gear

Video link: https://drive.google.com/file/d/1FTHdLXYqljBi2k0Bo8fuXrAuJ57I1Vqo/view?usp=sharing

CASE 2

Input	Output	Fixed
Ring Gear	Carrier	Sun Gear

Video link: https://drive.google.com/file/d/1_IbGKr_7Us4FXK01lpI60_cgPCuPyXpH/view?usp=sharing

CASE 3

Input	Output	Fixed
Sun Gear	Ring Gear	Carrier

Video link:

https://drive.google.com/file/d/1-w-p0H_7mZ8qPnnhDeSjUrEcIRGpAsNq/view?usp=sharing

Conclusions:

Case 1: Angular velocity is approximately constant without varying much.

Case 2: Angular velocity is varying at different intervals of time.

Case 3: Angular velocity is varying between 30 to 40 deg/sec.