F15B 2211/3111
The pump port being closed in the centre position
Official title: the pump port being closed in the centre position, e.g. so-called closed centre
F15B2211/3111 (The pump port being closed in the centre position) appears on 463 US grants and 283 published applications in this corpus.
Search patents in F15B- Granted patents
- 463
- Published applications
- 283
- Assignees
- 187
- Inventors
- 773
- Latest grant
- 6 Oct 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 11 | 0 |
| 1977 | 5 | 0 |
| 1978 | 5 | 0 |
| 1979 | 10 | 0 |
| 1980 | 4 | 0 |
| 1981 | 4 | 0 |
| 1982 | 5 | 0 |
| 1983 | 2 | 0 |
| 1984 | 1 | 0 |
| 1985 | 6 | 0 |
| 1986 | 7 | 0 |
| 1987 | 6 | 0 |
| 1988 | 3 | 0 |
| 1989 | 5 | 0 |
| 1990 | 6 | 0 |
| 1991 | 10 | 0 |
| 1992 | 8 | 0 |
| 1993 | 15 | 0 |
| 1994 | 12 | 0 |
| 1995 | 10 | 0 |
| 1996 | 9 | 0 |
| 1997 | 5 | 0 |
| 1998 | 14 | 0 |
| 1999 | 9 | 0 |
| 2000 | 10 | 0 |
| 2001 | 21 | 1 |
| 2002 | 21 | 12 |
| 2003 | 13 | 24 |
| 2004 | 15 | 19 |
| 2005 | 21 | 18 |
| 2006 | 9 | 13 |
| 2007 | 11 | 18 |
| 2008 | 12 | 15 |
| 2009 | 10 | 10 |
| 2010 | 13 | 9 |
| 2011 | 10 | 12 |
| 2012 | 6 | 10 |
| 2013 | 8 | 9 |
| 2014 | 8 | 4 |
| 2015 | 5 | 8 |
| 2016 | 4 | 7 |
| 2017 | 8 | 6 |
| 2018 | 8 | 9 |
| 2019 | 6 | 8 |
| 2020 | 11 | 14 |
| 2021 | 14 | 7 |
| 2022 | 9 | 8 |
| 2023 | 7 | 13 |
| 2024 | 8 | 15 |
| 2025 | 16 | 9 |
| 2026 | 7 | 5 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
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