Subtopic: Functional requirements, principles of working, construction and operation of manual, animal, tractor and renewable energy operated equipment for tillage, sowing, planting, fertilizer application, inter-cultivation, spraying, mowing, chaff cutting, harvesting and threshing
Question Statement:
In a combine harvester, the tangential threshing cylinder primarily separates grain from earheads by:
Options:
(A) Impact and rubbing action between the high-speed cylinder rasp bars and stationary concave grate
(B) Aerodynamic suction fans
(C) Centrifugal cyclone separation
(D) Optical sensor sorting
Answer Key:
A
Step-by-Step Solution & Explanation
Rasp bars impact seed heads, rubbing them across the concave grate where $70-90\%$ of grains are threshed and separated.