As beans fall into bins, photoelectric cells detect duds, signaling for them to be rejected individually with a puff from an air nozzle.

• 方式是在豆子落入容器的过程中，利用光电管挑出其中的坏豆子，然后送讯号给空气喷嘴对准一吹，将坏豆子个别剔除。