Internal Geneva Mechanism
AIM : Internal Geneva Mechanism
INTRODUCTION:
The Geneva drive or Maltese cross is a gear mechanism that translates a continuous rotation movement into intermittent rotary motion.
The rotating drive wheel is usually equipped with a pin that reaches into a slot located in the other wheel (driven wheel) that advances it by one step at a time. The drive wheel also has an elevated circular blocking disc that "locks" the rotating driven wheel in position between steps.
An internal Geneva drive is a variant on the design. The axis of the drive wheel of the internal drive can have a bearing only on one side. The angle by which the drive wheel has to rotate to effect one step rotation of the driven wheel is always smaller than 180° in an external Geneva drive and always greater than 180° in an internal one, where the switch time is therefore greater than the time the driven wheel stands still. The external form is the more common, as it can be built smaller and can withstand higher mechanical stresses.
- Create 3D models for driver and driven wheels.
- Perform motion analysis by rotating the driver wheel at 10rpm.
- Obtain the following plots
- Contact force (between driving and the driven wheel) as a function of time.
- Angular Displacement of the driven wheel.
- Compare the contact forces with and without "Precise contact"
- Show image for precise contact selection
- Use 60 Frames per second for 10 rpm and then 120 Frames per second for 20 Rpm
- Once you have completed the previous study, change the rpm to 20
- Make a plot of the driver wheel's angular velocity and discuss the results
- Internal Geneva Mechanism with dimension
First we have make driver and driven wheel separately in solidwork ,and the we have make assembly in solidwork.
After assemble we click on “SOLIDWORK motion” and select on “motion Analysis” to start dynamic
After this we select give RPM to driver wheel,
for contact forces with ( Precise contact )
60 Frames per second for 10 rpm
- Angular displacement
- contact forces without ( Precise contact )
- contact forces with ( Precise contact )
- Angular velocity
120 Frames per second for 20 rpm
- Angular displacement
- contact forces without ( Precise contact )
- contact forces ( Precise contact )
- Angular velocity