Intermediate card and a web-production process
AssigneeSpinnbau GmbH
InventorsWerner Lasenga, Jurgen Andermann
Life of this patent
Estimating the term…
Abstract
A method and apparatus for producing a web of non-woven fibrous material which is cross-linked in the carding step by means of an intermediate card. There is a main cylinder with two web forming rollers engaging the main cylinder, each taking off one card web. One of the web forming rollers is a random roller for producing a random orientation of the card web. The random roller has associated with it a trough plate with a space between the roller and plate. The space tapers toward the discharge end resulting in stuffing or compression on the web until the web exits to a free non-woven forming zone. Two card webs form a single web, which is taken off the card.
Claims22
Intermediate card for producing a web of fibrous material, comprising
- a main cylinder (1),
- two web-forming rollers (2, 4;
- 2, 6) in engagement with the main cylinder (1), each taking off one card web from the main cylinder (1), wherein at least one of the web-forming rollers (2, 4) in engagement with said main cylinder (1) is a random roller for producing a random orientation of the card web (3, 5) with an associated trough plate (30, 36) forming a centrifugal trough the random roller and its associated trough plate separated by a space, and wherein the space between the random roller and the trough plate tapers toward a discharge end causing a stuffing effect on the web, the trough plate ending in a distance of a predetermined length to form a free nonwoven forming zone, the random roller having an indentation with a front rake forming an acute angle,
- a doffer device (6, 8) downstream of and in engagement with the web-forming rollers (2, 4;
- 2, 6),
- a common roller (6, 10, 12) cross-linking at least two card webs (3, 5) to a single web (9) taken from the main cylinder (1) by the web-forming rollers (2, 4;
- 2, 6), and
- a take-off device (14, 16) for taking off the single web (9) at the end of the card.
Process for producing a nonwoven of fibrous material by means of an intermediate card comprising the steps of:
- carding the fibrous material on a main cylinder (1) in a carding step,
- taking off at least two card webs (3,5) from the main cylinder (1) by means of at least two rollers (2, 4, 2, 6;
- 2, 8) independent of each other in a web-forming stage,
- producing a random orientation of at least one card web (3, 5) between the main cylinder (1) and the at least one doffer device (6, 8) by using at least one web-forming random roller (2, 4) producing a random orientation of the card web (3, 5) and with a centrifugal trough (30, 36) associated with each random roller (2, 4),
- subjecting the card web (3, 5) initially to a stuffing effect by reducing the space between the random roller (2, 4) and the trough plates (30, 36) in a working direction and then the card web being suddenly released from the stuffing pressure in a free nonwoven forming zone immediately before taking over the webs in a doffer stage,
- taking over the card webs (3, 5) in the doffer stage by means of a doffer device (6),
- joining the card webs (3, 5) formed in the web-forming stage by uniting the card webs (3, 5) on a common roller to form a cross-linked card web (9), and
- taking off the card webs (3, 5) after the doffer stage.
Dependencies are inferred from the claim text.