Device for grinding coffee beans

A device for grinding coffee beans comprising:

• a housing assembly having a housing, a supporting member, and an outer grinding member, wherein the supporting member and the outer grinding member are arranged in the housing;
• a shaft assembly having a shaft and an inner grinding member, wherein the inner grinding member, comprising a ferromagnetic material, is arranged on the shaft, the shaft penetrates through the supporting member, there is a grinding gap between the inner grinding member and the outer grinding member, rotation of the shaft rotates the inner grinding member relative to the outer grinding member to grind coffee beans in the grinding gap;
• a fixing member fixing the supporting member and the shaft;
• and
• a brush assembly having a brush base and at least one brush member thereon, and the brush base is provided with at least one magnet, wherein when the brush base is fixed to a bottom of the inner grinding member through the at least one magnet, rotation of the shaft assembly rotates the brush base to brush away coffee powder remaining in the grinding gap.