D21D 5/023
Stationary screen-drums
Official title: {Stationary screen-drums}
D21D5/023 (Stationary screen-drums) appears on 229 US grants and 83 published applications in this corpus.
Search patents in D21D- Granted patents
- 229
- Published applications
- 83
- Assignees
- 91
- Inventors
- 237
- Latest grant
- 30 Dec 2025
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 5 | 0 |
| 1977 | 3 | 0 |
| 1978 | 6 | 0 |
| 1979 | 4 | 0 |
| 1980 | 7 | 0 |
| 1981 | 7 | 0 |
| 1982 | 5 | 0 |
| 1983 | 5 | 0 |
| 1984 | 4 | 0 |
| 1985 | 1 | 0 |
| 1986 | 4 | 0 |
| 1987 | 8 | 0 |
| 1988 | 5 | 0 |
| 1989 | 3 | 0 |
| 1990 | 8 | 0 |
| 1991 | 14 | 0 |
| 1992 | 10 | 0 |
| 1993 | 9 | 0 |
| 1994 | 8 | 0 |
| 1995 | 6 | 0 |
| 1996 | 9 | 0 |
| 1997 | 8 | 0 |
| 1998 | 3 | 0 |
| 1999 | 5 | 0 |
| 2000 | 12 | 0 |
| 2001 | 7 | 5 |
| 2002 | 4 | 2 |
| 2003 | 10 | 4 |
| 2004 | 4 | 11 |
| 2005 | 3 | 5 |
| 2006 | 1 | 7 |
| 2007 | 3 | 7 |
| 2008 | 1 | 3 |
| 2009 | 2 | 3 |
| 2010 | 2 | 4 |
| 2011 | 2 | 1 |
| 2012 | 3 | 3 |
| 2013 | 2 | 3 |
| 2014 | 4 | 2 |
| 2015 | 2 | 3 |
| 2016 | 1 | 1 |
| 2017 | 1 | 1 |
| 2018 | 2 | 3 |
| 2019 | 1 | 4 |
| 2020 | 4 | 3 |
| 2021 | 2 | 0 |
| 2022 | 1 | 1 |
| 2023 | 0 | 2 |
| 2024 | 4 | 3 |
| 2025 | 4 | 0 |
| 2026 | 0 | 2 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Pulp screening machine30 Dec 2025US 12,509,824 B2ANDRITZ (China) Ltd.
- Paper pulp pressure screen16 Dec 2025US 12,497,735 B1
- Rotor with forward-swept struts for pressure screen cylinders14 Oct 2025US 12,440,870 B2Kadant Black Clawson LLC
- Multistage screen sorting device4 Mar 2025US 12,239,997 B2Voith Patent GmbH
- Pressure screen for a fiber web product process with removable cover29 Oct 2024US 12,129,599 B2Valmet Technologies Oy
- Screen, in particular pressure screen2 Apr 2026US 2026/0091329 A1Andritz Fiedler GmbH
- Rotor with forward-swept struts for pressure screen cylinders15 Jan 2026US 2026/0014591 A1Kadant Black Clawson LLC
- Rotor with forward-swept struts for pressure screen cylinders31 Oct 2024US 2024/0359215 A1Kadant Black Clawson LLC
- Multistage screen sorting device29 Feb 2024US 2024/0066527 A1Voith Patent GmbH
- Pressure Screen for a Fiber Web Product Process with Removable Cover29 Feb 2024US 2024/0068162 A1Valmet Technologies Oy
Most cited
By later US patents
- Integrated paper pulp and process machinery having integrated drive and control and methods of use thereof85US 6,617,720 B1Kadant Black Clawson LLC · 2003
- Method for screening pulp47US 5,601,690 AGauld Equipment Company · 1997
- Method and apparatus for treating fiber suspension36US 5,000,842 AA. Ahlstrom Corporation · 1991
- Apparatus for the purification of paper pulp26US 4,200,537 AE et M Lamort · 1980
- Apparatus for screening paper fiber stock23US 4,276,159 AThe Black Clawson Company · 1981