D21F 5/04
On two or more drying cylinders
Official title: on two or more drying cylinders
D21F5/04 (On two or more drying cylinders) appears on 446 US grants and 118 published applications in this corpus.
Search patents in D21F- Granted patents
- 446
- Published applications
- 118
- Assignees
- 91
- Inventors
- 501
- Latest grant
- 4 Aug 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 1 | 0 |
| 1977 | 1 | 0 |
| 1978 | 2 | 0 |
| 1979 | 1 | 0 |
| 1980 | 6 | 0 |
| 1981 | 2 | 0 |
| 1982 | 2 | 0 |
| 1983 | 2 | 0 |
| 1984 | 9 | 0 |
| 1985 | 10 | 0 |
| 1986 | 5 | 0 |
| 1987 | 9 | 0 |
| 1988 | 3 | 0 |
| 1989 | 14 | 0 |
| 1990 | 18 | 0 |
| 1991 | 23 | 0 |
| 1992 | 18 | 0 |
| 1993 | 16 | 0 |
| 1994 | 16 | 0 |
| 1995 | 22 | 0 |
| 1996 | 33 | 0 |
| 1997 | 22 | 0 |
| 1998 | 30 | 0 |
| 1999 | 37 | 0 |
| 2000 | 26 | 0 |
| 2001 | 15 | 4 |
| 2002 | 16 | 11 |
| 2003 | 8 | 8 |
| 2004 | 7 | 6 |
| 2005 | 7 | 7 |
| 2006 | 8 | 10 |
| 2007 | 1 | 6 |
| 2008 | 6 | 7 |
| 2009 | 5 | 12 |
| 2010 | 4 | 5 |
| 2011 | 3 | 5 |
| 2012 | 5 | 0 |
| 2013 | 4 | 1 |
| 2014 | 0 | 0 |
| 2015 | 0 | 2 |
| 2016 | 1 | 4 |
| 2017 | 1 | 0 |
| 2018 | 2 | 7 |
| 2019 | 2 | 4 |
| 2020 | 6 | 7 |
| 2021 | 5 | 3 |
| 2022 | 3 | 3 |
| 2023 | 3 | 1 |
| 2024 | 3 | 3 |
| 2025 | 2 | 2 |
| 2026 | 1 | 0 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Fibrous structures4 Aug 2026US 12,698,594 B2The Procter & Gamble Company
- Formation detection system and a process of controlling18 Nov 2025US 12,473,690 B2IBS of America
- Creped fibrous structures15 Jul 2025US 12,359,376 B2The Procter & Gamble Company
- Fibrous structures30 Apr 2024US 11,970,818 B2The Procter & Gamble Company
- Formation detection system and a process of controlling5 Mar 2024US 11,920,299 B2IBS of America
- Cylinder for Drying a Fibrous Web18 Sep 2025US 2025/0290695 A1Andritz Inc.
- Continuous papermaking machines and methods for continuous papermaking20 Mar 2025US 2025/0092602 A1
- Fibrous Structures11 Jul 2024US 2024/0229357 A1The Procter & Gamble Company
- Formation Detection System and a Process of Controlling20 Jun 2024US 2024/0200268 A1IBS of America
- Seal strip temperature monitoring systems and assemblies therefor14 Mar 2024US 2024/0085244 A1Stowe Woodward Licensco, LLC
Most cited
By later US patents
- Device in the drying section of a paper machine63US 4,441,263 AValmet Corporation · 1984
- Paper machine drying section and method for operating same58US 4,202,113 AValmet Corporation · 1980
- High speed paper drying58US 4,359,827 AWeyerhaeuser Company · 1982
- Method and machine for drying a material web with guide rollers58US 5,829,164 AVoith Sulzer Papiermaschinen GmbH · 1998
- Vacuum box for use in high speed papermaking56US 4,359,828 AWeyerhaeuser Company · 1982