The invention discloses a device for cleaning profile fibers of negative-pressure seed cotton. The device for cleaning the profile fibers comprises a shell. The interior of the shell is divided into a separating area and a profile
fiber collecting area; a feeding port and a discharging hole are connected at the separating area, and an
impurity discharging hole is connected at the profile
fiber collecting area; wind stopping devices are arranged at the discharging hole and the
impurity discharging hole respectively, and an opening and
casting roll is arranged at the feeding port; a long-hole dust cage is arranged at the communicating position of the separating area and the profile
fiber collecting area, an air hose communicated with the end part of the shell is arranged outside the shell, and a draught fan is connected at the air hose end; and a baffle plate which is approximately tangent to the long-hole dust cage is arranged in the shell, and an
impurity brushing device is arranged in the profile fiber collecting area close to the long-hole dust cage. The long-hole dust cage is arranged in the shell of the profile fiber cleaning device, therefore, small profile fibers in the seed cotton can be winnowed by strong negative-pressure wind, the light and small profile fibers are absorbed into a rotary drum and discharged out through an exhausting
pipe, a local strong wind area is formed on the surface of the long-hole dust cage through the impurity brushing device when in
air separation, and large profile fibers absorbed on the surface of the long-hole dust cage are blown away and collected and discharged through the special separating area so as to prevent the profile fibers from being mixed in cotton secondarily.