Ring-shaped This is done by a great number of ring-shaped air jets on the bottom of the craft. 船底装上大量环状喷气嘴以实现这一目的。
The basic mechanism is an air jet supplied by an accurately regulated pressure. 其基本机械结构是一个空气喷嘴，喷嘴压力经过精确调整。
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。
