| 摘要 |
PURPOSE:To obtain an optimum ball rotary state over a wide number-of-rotation range by preventing the slippage of balls, by arranging projections each having a triangular shape crossing at a right angle to each other in a rotary direction to the inner wall of a bottomed cylindrical vessel-shaped rotary ball mill at an almost equal interval. CONSTITUTION:Balls 3 each formed by covering an iron ball with a resin in order to prevent the mixing of impurities, a ceramics powder to be ground and a dispersing medium are charged in a ball mill which is, in turn, rotated. In this case, the balls are prevented from slipping along the inner wall surface of the ball mill as is conventional by the action of projections having a semicircular or triangular cross-section arranged to the inner wall surface of the ball mill and optimum rotary motion (cascade phenomenon) wherein the balls slip down in avalanche is held over a wide number-of-rotation range. Further, the projections may be arranged in a zigzag pattern. Said ball mill has high utility value, especially, as an apparatus for producing a ceramic powder for electronic parts. |
