Internal Geneva Mechanism
Internal Geneva Mechanism
Aim:
To study the motion analysis of Internal Geneva Mechanism by creating 3D models of driver and driven wheels of the internal geneva mechanism.
Objective:
- To determine the contact force between driver and driven wheel.
- Compare the contact force plot with and without precise contact.
- To determine the angular velocity of driver wheel.
- To determine the angular displacement of driven wheel.
Theory:
- In this mechanism, the drive wheel and driven wheel are connected internally, hence it is known as Internal Geneva Mechanism.
- In this mechanism the step rotation magnitude (angle) will be high compared to External Geneva Mechanism.
- We can change the frequency of the intermittent rotary motion by varying the number of slots in the driven wheel.
Modelling and Assembly of the driver and driven wheel
- Driver wheel
- Driven wheel
- Assembly of Internal Geneva Mechanism
- Assembly Drawing of Internal Geneva Mechanism in solidworks
https://drive.google.com/file/d/1lTzYr6eLGGmeDgOMRQqCQualQjGfw63V/view?usp=sharing
- Results
- For 10 RPM
- Contact force between driver and driven wheel (without precision contact)
- Contact force with precision of 60 frames per second @10 rpm
- Angular Displacement of driven wheel @ 10 rpm
- Angular velocity of driver wheel @ 10 rpm
- For 20 RPM
- Contact force between driver and driven wheel (without precision contact) @20 rpm
- Contact force with precision of 120 frames per second @20 rpm
- Angular Displacement of driven wheel @ 20 rpm
- Angular velocity of driver wheel @ 20 rpm
- Motion Analysis of Internal Geneva Mechanism
- Conclusion
- The 'precise contact' gives the more accurate result compared to motion without precise contact as we see that curves the plots with precise contact becomes less fluctuating and smooth.
- From the graph of contact force between driver and driven wheel,we can conclude that if we increase the rotation of the driver wheel contact force at the entry also increases and then decreases.
- The angular displacement plot shows that the displacement occurs between -180 to 180 degree.
- If we increase the frames per second(FPS) then it does not effect on the angular velocity of wheels but slightly changes the graph.
- Angular velocity of the driver wheel increases with increases in time and then decreases @10 RPM as shown in plot.
- Angular velocity of the driver wheel increases and constant for some time then dreases as shown in plot.