KR930700286A - Method and apparatus for improved double wire forming - Google Patents

Abstract

Disclosed is an improvement to twin wire forming wherein an open support structure in the form of an opened or grilled breast roll or a slotted forming shoe supports at least a portion of the outer wire in the forming throat. In such manner, the gap between the open support structure and the forming cylinder can be narrowed such that the gap is less than or equal to the thickness of the jet of stock injected between the wire to form the web. The jet of stock so injected impinges on both the forming cylinder and the open support structure and immediate drainage is provided through the outer wire without substantially varying the tension or radius of the outer wire thereby generally improving uniformity and, in particular, improving basis weight uniformity of the web produced.

Description

Method and apparatus for improved double wire forming

Since this is an open matter, no full text was included.

1 is a basic schematic diagram of a forming roll / breast roll configuration which is a typical prior art for a double wire forming machine.

2 is a basic schematic view of the forming roll / open breast roll of the present invention.

3 is a partial cross-sectional view of one open breast roll showing its contoured surface.

Claims (20)

A method of producing a web from a jet of stock injected with a forming draw between an outer and an inner forming wire moving around a peripheral portion of a forming cylinder, the method comprising: supplying an open support structure to the outer wire, the forming cylinder and the And wherein the jet of the stock is directed to impinge on both support structures. A method of producing a web from a jet of stock injected with a forming draw between an outer and an inner forming wire moving around a peripheral portion of a forming cylinder, the method comprising: supplying the wire opening support structure and supplying the open support structure and the forming Positioning the open support structure such that a gap between cylinders is less than or equal to the jet thickness of the stock and directing the jet of the stock to impinge both the forming cylinder and the open support structure. Web production method. A method of producing a web from a jet of stock injected with a forming draw between an outer and an inner forming wire moving around a peripheral portion of a forming cylinder, the method comprising: simultaneously producing both the inner and outer forming wires of the forming drop. A method of impacting the jet of the stock and supplying an open support structure to the outer wire over at least a portion of the forming draw to enable immediate drainage through the outer wire. A method of producing a web from a jet of stock injected into a forming draw between an outer and an inner forming wire moving around a peripheral portion of a forming cylinder, the method comprising: opening support structure to the outer draw on at least a portion of the forming draw Supplies a gap, sets a gap between the open support structure and the forming cylinder that is less than or equal to the jet thickness of the stock, impinges on the external wire where the external wire is supported by the open support structure, and simultaneously Orienting the jet of the stock so as to impinge on the forming cylinder. The method of claim 1 wherein the open support structure is a breathtrol having a plurality of circumferential grooves therein. The method of claim 1 wherein the open support structure is an open breast roll. The method of claim 1, wherein the open support structure is a cylindrical breaststroke having a plurality of orifices on the cylindrical surface. The method of claim 1 wherein the open support structure is a molded shoe having a wire contact surface, the wire contact surface having a plurality of channels therein. The method of claim 1, wherein about one third of the jet thickness of the stock impinges on the open support structure. The method of claim 1, wherein the open support structure is pivotally mounted such that an angle between the inner and outer forming wires of the forming draw is deformed. Rotatable forming cylinders, inner and outer annular forming wires, means for supporting them so that the inner and outer annular forming wires form a forming drop and then gather in a line to move together on the surface portion of the forming cylinder and the web A web forming apparatus consisting of a headbox means for injecting a jet of stock into the forming draw between the forming wires, the web forming apparatus comprising: an open support structure for supporting the outer wire over at least a portion of the forming draw, the jet of stock Wherein the narrowed gap between the forming cylinder and the open structure is improved such that the forming cylinder and the open support structure generally collide with both of the forming cylinder. 12. The web forming apparatus of claim 11, wherein the open support structure is an open breast roll. The web forming apparatus according to claim 11, wherein the open support structure is a breast roll having a plurality of annular grooves therein. 12. The web forming apparatus of claim 11, wherein the open support structure is a cylindrical breast roll having a plurality of orifices on its cylindrical surface. 12. The web forming apparatus according to claim 11, wherein the open support structure is a molded shoe having a wire contact surface, the wire contact surface having a plurality of channels therein. Rotatable forming cylinders, inner and outer annular forming wires, means for supporting the wires so that they are gathered in a line to move together over the surface portion of the forming cylinder after forming forming molds and the wires forming webs A web forming apparatus comprising a head box means for injecting a jet of a stock into said forming draw between said open forming structure supporting said outer wire on at least a portion of said forming draw, said jetting cylinder and said jet thickness of said stock A web forming apparatus comprising an improved gap between said open support structures that is narrower. 12. The web forming apparatus according to claim 11, wherein the open support structure is pivotally mounted such that an angle between the inner and outer forming wires of the forming drop can be modified. 17. The web forming apparatus according to claim 16, wherein the open support structure is pivotally mounted so that an angle between the inner and outer forming wires of the forming drop can be changed. 3. The web forming apparatus according to claim 2, wherein the open support structure is pivotally mounted such that an angle between the inner and outer forming wires of the forming draft is deformed. 5. The web forming apparatus according to claim 4, wherein the open support structure is pivotally mounted such that an angle between the inner and outer forming wires of the forming draft is deformed. ※ Note: The disclosure is based on the initial application.