PURPOSE: To prevent fine powder pulverized in a pulverization chamber from being infiltrated into the inside of a bearing for supporting the rotary shaft of a grinding disk in a pulverizing device having a form wherein argon gas and other atmospheric gas are introduced into the pulverization chamber.

CONSTITUTION: This device for pulverizing and classifying powder of active metal is constituted of a housing comprising a pulverization chamber 3, a rotary disk 6 and a stationary disk 7 held therein. The bearing 8 of a horizontal rotary shaft 5 supporting the rotary disk 6 is arranged in the outside of the housing 4. Further a closing cover 9 for introducing atmospheric gas into the pulverization chamber 3 is so provided that a closing state is formed in the connection part of a housing 4 and the bearing 8. The injection port 10 of atmospheric gas is provided in the housing 4 and the closing cover 9, respectively. Thereby the device is constituted so as to introduce atmospheric gas into the pulverization chamber 3 from the inside of the closing cover 9.