Abstract: This invention relates to methods for forming a nonwoven fibrous web on a foraminous forming surface moving at a velocity in excess of about 500 feet per minute. In forming satisfactory uniform webs, the fibers are conveyed to the forming surface in a gaseous stream whereby the relative surface-to-fiber velocity along the moving surface is maintained within a critical ratio relative to the fiber velocity normal to the moving surface.

Abstract: Process is disclosed which is suitable for high speed production of uniform, lightweight webs by air-laydown of textile fibers. A toothed disperser roll doffs the fibers into an air stream of high uniform velocity and low turbulence to form a thin fiber layer from which the fibers are deposited in web form on a moving screen. A curved disperser plate, shrouds a portion of the disperser roll up to the point of fiber doffing. By using a disperser plate with a rough surface, preferably one having lateral grooves, web uniformity is remarkably improved.

Abstract: An apparatus and method for fluid-forming (e.g., air-forming) a fibrous structure, such as a fibrous web, employs a conveying duct through which a stream of fluid-entrained fibers is directed, and a foraminous surface intercepting the downstream end of the duct to collect the fibrous structure on its surface. The improvement resides in establishing an oblique orientation between the foraminous surface and the direction of fiber flow through the duct so that the width of the foraminous surface intercepting the open end of the duct is greater than the width of the downstream end of the duct, as measured between laterally spaced sidewalls in a direction generally normal to the direction of material flow through the duct. In accordance with this invention the width of the fibrous structure deposited on the foraminous surface is greater than the width of the stream of fluid-entrained fibers confined within the conveying duct.

Abstract: A method for forming a fibrous structure from a fibrous feed by: (1) directing the feed into engagement with projections on a rotating fiberizing drum for separating fibers from the feed; (2) directing the separated fibers to a release zone at which they are released from the periphery of the drum for subsequent conveyance to a foraminous forming surface upon which the fibrous structure is formed; and (3) sealing the outer periphery of the drum in a region between the fiber release zone and the region in which the fibrous feed is directed into engagement with the fiberizing drum by directing a gas against the outer periphery of the drum with a force component in a direction opposed to the direction of rotation of the drum and at a static pressure of at least about two atmospheres to provide a gas velocity which is sufficiently high to remove air trapped between the projections of the drum as the drum is being rotated.

Abstract: The invention resides in a method of forming a nonwoven web by employing a forming apparatus which includes a fiberizing roll for separating fibers from a feed mat and entraining them in a gaseous medium, a foraminous forming surface through which the gaseous medium passes and upon which the fibers are condensed to form a fibrous web, and a formation duct between the fiberizing roll and the forming surface for defining a flow path for the gaseous suspension of fibers from the fiberizing roll to the forming surface; the improvement wherein the formation duct includes front and back, substantially planar inner surfaces which may slightly converge in a direction from the fiberizing roll to the forming surface, but preferably diverge at an angle of up to about 41/2 degrees when the forming surface is a curved surface of a cylindrical drum, and up to about 11/2 degrees when the forming surface is a linear surface of a forming belt; the formation duct being inclined to the forming surface to define an incidence ang

Abstract: In this machine, tufts of fibers are delivered from a feed section by an air bridge into a generally vertical chute past a rotary feeder condenser on which the fibers are formed into a mat which is carried onto a feed plate over which the mat is fed by a feed roller into a lickerin rotating at high speed. The lickerin, which is vertically below the condenser, combs fibers from the mat. The fibers are doffed from the lickerin through centrifugal force and by an air stream flowing past the lickerin. The air stream conveys the fibers through a generally vertical duct to an endless belt screen condenser on which they are deposited to form the random fiber web. The air is recirculated past the lickerin to aid in doffing the fibers from the lickerin.