In rural areas, there is a farm tool called Fengpo, which is like a fan. When you shake it with your hand, you can blow away the impurities in the grain.

Manual valley blower, referred to as valley blower, also known as valley blower, valley elevator, windmill, fan car, fan car. This is a traditional wooden farm tool, which is used to remove impurities, shriveled grains, straw scraps and so on from the seeds of crops such as rice. It consists of a container, an air outlet, a hand fan and an air outlet.

Fan car, that is, fan car, is an agricultural tool invented by the working people in ancient China, which is used to remove glume, gray chaff and shriveled grains from grains. It is a machine that can generate wind (or airflow), also called "fan", "grain elevator", fan car or lift car. Invented in the Han Dynasty, it was propelled by human power and used to clean grain.

In the 2nd century BC, China people invented the rotary grain-raising fan. Van is the most mechanized farm tool in rural areas before the popularization of modern agricultural machinery. The fan is essentially a manual blower, and its function is to separate the grains and impurities of the crushed cereal crops and make the grains pure.