Abstract: An efficient, highly porous fabric filter medium capable of filtering air at temperatures up to about 500.degree. F. (260.degree. C.) has been provided. The filter medium is made from a polyimide fiber and is especially well suited for use in combination with a rotating drum filtering machine, thereby providing high temperature air filtration at a lower initial equipment and installation cost, and with subsequent lower operating and maintenance costs than have been previously possible.

Abstract: Apparatus to remove dust, fibers, lint or other undesirable particles from air. Air ladened with dust, lint or other undesirable matter is drawn into a filtering housing to contact the surface of a rotatable screen-covered drum. The air passes through the drum while the particles remain on the drum surface. The air passes from a higher pressure area exterior of the drum into a lower pressure area within the center of the drum and is conveyed away. The particles are retained on the exterior surface of the drum which is covered by the fine mesh screen. The particles, which form a bat, are then separated from the rotating drum surface by being moved into contact with a smooth compressor roll cooperating with a flighted doffing to lift away the bat from the drum and drop it to a collection zone.A supplemental doffing roll with rigid flights is rotated parallel to the axes of the compression roll and flighted doffing roll in such manner as to interfere with the rotation of urethane flights of the doffing roll.

Abstract: Air filtering apparatus with electric controls for varying the speed of filtering as a function of the contamination within the air being filtered. Pressure sensing devices are provided at the input and output ends of the filtering apparatus. The sensing devices are coupled with the electrical controls to either speed up or to slow down the filter cleaning mechanisms when appropriate.

Abstract: Wrapping sheets are propelled across the opposed platens of a baling press. After compression, the press box is removed from the bale, and thereafter wrapper folding members move along the bale walls to fold the freed edge portions of the wrapping sheets thereagainst. Finally, while the folds are held, securing bands are applied about the bale which is then released and removed.