Device for the elimination of dirt from a fiber fleece

Abstract

A card including a main cylinder, a revolving flat as well as a licker-in roller and a doffing roller (also called a doffer roll) also includes a suction device in combination with a separating knife in order to improve the carding result and eliminate dirt in the precarding zone between the licker-in and the revolving flat, in the after carding zone between the revolving flat and the doffer roll as well as in the precarding zone between the doffer roll and the licker-in. A preparatory element has a structured surface arranged opposite to the surface of the main cylinder, in which the teeth are arranged facing the direction of rotation of the main cylinder. This structured surface allows the carding result to be retained and subjects the fleece lying on the main cylinder to a certain vibration so that, in combination with centrifugal force and the separating knife, there is better dirt separation which can be removed through the suction device. The precarding zone between the licker-in and the revolving flat can include a knife which differs from the knife in the after carding and precarding zone, in that it is not an independent element, but rather, is assigned to a card rod. With this arrangement, the carding result should be improved and the elimination of dirt on a card should also be improved. The arrangement can also be applied to all rollers carrying a fleece in which dirt must be eliminated from the fleece.