Yield measurement: Below is the link to a patent that describes the yield measurement in the forage harvester using torque measurement on the accelerator:

https://worldwide.espacenet.com/patent/search/family/046963387/publication/EP2570020A1?q=EP2570020

Intake auger: Here is the patent for the intake auger of the current Kemper pick-up with these specially shaped coil ends:

https://worldwide.espacenet.com/patent/search/family/037295149/publication/DE102005020462A1?q=DE102005020462

A flap in the drum housing intended to eject a stone that has been drawn in (position 43 on the drawing):

https://worldwide.espacenet.com/patent/search/family/009143077/publication/GB1480302A?q=US3995783