PURPOSE: To mix fiber materials and simultaneously cleaning the fiber materials by disposing horizontal parallel rollers and staple opening cylinders.

CONSTITUTION: Two rotary horizontal parallel toothed rollers 2 are in each vertical cell, and a staple opening cylinder 3 is disposed under the rollers 2. A vertical grid 4 is disposed close to the staple opening cylinder 3. A removing device such as a rotary warm screw 6 is disposed in a non-spinnable material collecting chamber 5. One end of a horizontal rectangular cross-section channel under the vertical cell 1 is closed by a closing grid 8. On the opposite end, the channel extends upward with a curved portion 9 through a suction duct 10, and is connected to a comb member 11. A blower 14 is disposed on the grid-disposed side of the channel, and a static negative pressure chamber 13 is disposed behind the comb member 11.