Method and apparatus for forming a fiber nonwoven

Abstract

An aerodynamic nonwoven formation, in which the nonwoven formation occurs in the operating range of a milling roller. The nonwoven formation takes place using a fiber opening unit, a moving screening surface with suction and a milling roller. The nonwoven-forming fibers are removed from the fiber opening roller and form a nonwoven after a flight or slide route. The nonwoven formation takes place in an area that is limited by an angle a against the direction of movement of the screen and by an angle β with the movement of the screen relative to a section from the center of the milling roller to the screening belt.

Claims

1. A method for forming a fiber nonwoven, the method comprising: sucking nonwoven-forming fibers or flakes onto a moving screening surface; operating a milling roller with a fiber-entraining surface in a suction area; and forming the nonwoven in a nonwoven formation area between the screening surface and the milling roller, the nonwoven formation area including an initial area and an end area, the initial area of the nonwoven formation area being defined by a first intersection of a first straight line originating from the center of the milling roller with the screening surface, the first straight line forming, together with a section extending perpendicular from the center of the milling roller to the screening surface, a first angle (α) of 0° to 20° against the direction of movement of the screening surface, and the end area of the nonwoven formation area being defined by a second intersection of a second straight line originating from the center of the milling roller with the screening surface, the second straight line forming with the section a second angle (β) of 0° to 30° in the direction of movement of the screening surface.

2. The method according to claim 1, further comprising feeding nonwoven- forming fibers or flakes onto the moving screening surface from a fiber opening roller; and transporting the nonwoven-forming fibers or flakes with the moving screening surface along a flight or slide route to the suction area located downstream from the fiber opening roller.

3. A device for forming a fiber nonwoven, the device comprising: a moving screening surface onto which nonwoven-forming fibers or flakes are to be sucked; a milling roller with a fiber-entraining surface located at a suction area; and a nonwoven formation area located between the screening surface and the milling roller, the nonwoven formation area being defined by a first intersection of a first straight line originating from the center of the milling roller with the screening surface, the first straight line forming, together with a section extending perpendicular to the screening surface from the center of the milling roller, a first angle (α) of 0°-20° against the direction of movement of the screening surface and by a second intersection of a second straight line originating from the center of the milling roller with the screening surface, the second straight line forming with the section a second angle (β) of 0° to 30° in the direction of movement of the screening surface.

4. The device according to claim 3, further comprising a fiber opening roller configured to feed the nonwoven-forming fibers or flakes onto the moving screening surface.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 shows one embodiment example of the disclosure.

DETAILED DESCRIPTION

(2) The fibers are fed to the system via an opening unit consisting of a feeder and a cylinder.

(3) The fibers also come off from the roller 1) using a knife 2). Troughs 3) prevent premature removal of the fibers from the garnished cylinders.

(4) A screening belt 4) moves from the fiber feed towards the milling roller 5).

(5) A low pressure is generated at a suction box 6), and a nonwoven 7) is formed. The nonwoven is produced below the milling roller 5), i.e. in an area 8) which is defined by angles α) and β) with respect to the section from the center of the milling roller to the screening belt.

(6) The slide or flight route 9) extends between the removal of the fibers/flakes from the cylinder 1) and the nonwoven formation.

(7) The nonwoven formation is thus carried out by means of a fiber opening unit, a moving screening surface 4) with a suction 6) and a milling roller 5), at which the nonwoven-forming fibers are removed from the fiber opening roller 1) and form a nonwoven after a flight or slide route 9), and the nonwoven formation occurs in an area 8) that is limited by an angle α against the direction of movement of the screen and by an angle β with the movement of the screen. On section 9), i.e. from the removal of the fibers/flakes up to approximately the nonwoven formation, the fibers fly or slide individually or in flakes.

(8) In earlier applications, it was assumed that the nonwoven is formed in front of the operating range of the milling roller 5). This causes a rolling of the fibers and results in a non-uniform nonwoven. The formation of the nonwoven in the direct operating range of the milling roller makes the nonwoven more uniform and allows the production of nonwovens having a predetermined MD/CD.

(9) The disclosure comprises the following method and the following device:

(10) 1) A method for forming a fiber nonwoven, in which fibers or flakes are sucked onto a moving screening surface. A milling roller operates in the suction area, and the nonwoven formation occurs in an area between the screening surface and the milling roller. The initial area of the nonwoven formation is to be impinged by a beam from the center of the milling roller onto the screening surface, with the beam having an angle of 0° to 20° with respect to the section from the center onto the screening surface against the direction of movement of the screen. The end area is to be impinged by a beam having an angle of 0° to 30° with respect to the same section in the direction of movement of the screen.

(11) 2) A device for forming a fiber nonwoven, in which fibers or flakes are sucked onto a moving screening surface. A milling roller operates in the suction area, and the nonwoven formation occurs in an area between the screening surface and the milling roller. The suction area is to be impinged by a beam from the center of the milling roller onto the screening surface, with the beam having an angle of 0° to 20° with respect to the section from the center onto the screening surface against the direction of movement of the screen. The end area is to be impinged by a beam having an angle of 0° to 30° with respect to the same section in the direction of movement of the screen.