Internal Geneva Mechanism

Internal Geneva mechanism

Aim: To create a CAD model using solidworks of Internal Geneva mechanism and perform motion analysis on it to obtain Contact force and Angular displacement.

Internal Geneva mechanism:

Geneva internal mechanism is a mechanical mechanism that converts a continuous rotating motion into a sequence of intermediate motion. (i.e.) it converts one fell rotation of the driving wheel into (1/4) rotation of the driven wheel.

The mechanism consists of two circular disks, one is a driving wheel which consist of small rod projection at its span and the mechanism consist another driven wheel which contains + shaped slot on it in which the projection of the driving wheel moves.

Drive wheel

Driving Wheel

Complete Assembly

When ever the projection of the driving wheel movers over the slot in driven wheel it moves.

Objective of the project:

• To create a CAD model of Internal Geneva mechanism using soldworks.
• To perform a Motion analysis over the Geneva model with motor of 10 and 20 RPM.
• To obtain contact force between the driver projection and the slot wall.
• To obtain Angular displacement of the elements of the components.
• The motion analysis is done with and without precise motion analysis at 60 frames for 10rpm and 120 frames for 20 rpm.
• The plots of contact force for precise and without precise are compared for 10 as well as 20rpm.

Body of contact:

Motor at 10Rpm with 60fps

Contact foreces

These graph shows the contact force experience between the driving wheel projection and the driven wheel.

For this graph we can say that the force experienced is high when the projection hits the start of the slot were the force reaches up to 12000 N and are same in both with and without precise motion analysis.

Angular displacement

These graph shows the Angular displacement of driving wheel projection and the driven wheel.

The motion of both the plates are same which shows the same angular displacement.

Comparison of Contact force with and without precise

It shows that there is no difference in the contact force with and without precise.

Motor at 20rpm and 120fps

Contact force

These graph shows the contact force experience between the driving wheel projection and the driven wheel.

From the graph we can see that the Contact force with precise hits a maximum force of more than 21000N were as the contact force without precise experience a highest of less than 20000N.

Angular Displacement

These graph shows the Angular displacement of driving wheel projection and the driven wheel.

Compassion of 20 rpm contact force with and without precise

From the compassion graph we can clearly see that the contact force with and without precise has some variation with each other.

The force of contact of precise contact occurs early than the contact without precise motion analysis.

Motion analysis video link :https://youtu.be/okRhcgh2JUU

Conclusion: The motion analysis of Internal Geneva mechanism is done and it shows that the force of contacts varies with and without precise contact.