| US 5,972,168 C1 (6748th) | ||
| TWIN WIRE FORMER | ||
| Dieter Egelhof, Heidenheim, Germany; Klaus Henseler, Heidenheim, Germany; Werner Kade, Neenah, Wis.; Albrecht Meinecke, Heidenheim, Germany; Wilhelm Wanke, Heidenheim, Germany; Hans-Jurgen Wulz, Heidenheim, Germany; Rudolf Buck, deceased, late of Heidenheim, Germany, and by Elsie Buck, legal representative, Heidenheim, Germany, assignors to Voith Paper GmbH & Co. KG, Heidenheim, Germany | ||
| Reexamination Request No. 90/008,821, Aug. 24, 2007. | ||
| Reexamination Certificate for Patent 5,972,168, issued Oct. 26, 1999, Appl. No. 161,138, Sep. 25, 1998. | ||
| Continuation of application No. 09/023,435, filed on Feb. 13, 1998, now Pat. No. 5,853,544, which is a continuation of application No. 08/556,769, filed on Nov. 2, 1995, now Pat. No. 5,718,805, which is a continuation of application No. 08/286,948, filed on Aug. 8, 1994, now Pat. No. 5,500,091, which is a continuation of application No. 08/055,918, filed on Apr. 29, 1993, now Pat. No. 5,389,206, which is a continuation of application No. 07/773,965, filed as application No. P/EP1990/001313, filed on Aug. 9, 1990, now abandoned. | ||
| Claims priority, application Germany, Aug. 22, 1989, P3927597 | ||
| Int. Cl. D21F 1/00 (2006.01) | ||
| U.S. Cl. 162—203 |
| AS A RESULT OF REEXAMINATION, IT HAS BEEN DETERMINED THAT: |
| The patentability of claims 1-8 is confirmed. |
| 1. A method for the production of a paper web from a fiber suspension in a twin wire former comprising: causing first and second web forming wire belts to travel along a path together to form a twin wire zone of the twin wire former, with the web between the wire belts as the wire belts travel along the path through the twin wire zone, each wire belt forming an endless loop;
feeding the wire belts across a single forming roll at the start of the path through the twin wire zone;
supporting the wire belts such as to form a wedge shaped entrance slot into the twin wire zone;
supplying a fiber suspension from a headbox directly to the wedge shaped entrance slot of the twin wire zone;
draining water from the fiber suspension by means of the forming roll in order to start the forming of the web from the fiber suspension;
feeding the wire belts with the fiber suspension and the web being generated therebetween downstream of the forming roll between a plurality of first drainage strips, which are positioned within the loop of the first wire belt for contacting the first wire belt, and a plurality of second drainage strips, which are positioned within the loop of the second wire belt for contacting the second wire belt, the first strips being shifted in position along the path of the wire belts with respect to the second strips so that the first and second strips are offset and in a non-opposing relationship;
resiliently supporting the first drainage strips against the first wire belt that the strips contact;
rigidly supporting the second drainage strips against the second wire belt;
feeding the wire belts with the web therebetween down- stream of said drainage strips across a stationary drain- age element and then across a suction roll in the twin wire zone such that as the wire belts travel over the stationary drainage element and over said suction roll, water is drained through the wire belt in contact with said stationary drainage element and with said suction roll; and
maintaining the twin wire zone apart from said single forming roll and said suction roll free of rolls which would deflect the twin wire zone.
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