B43L 21/00
Blackboard or slate cleaning devices
B43L21/00 (Blackboard or slate cleaning devices) appears on 95 US grants and 62 published applications in this corpus.
Search patents in B43L- Granted patents
- 95
- Published applications
- 62
- Assignees
- 40
- Inventors
- 163
- Latest grant
- 15 Jul 2025
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 1 | 0 |
| 1977 | 0 | 0 |
| 1978 | 3 | 0 |
| 1979 | 0 | 0 |
| 1980 | 1 | 0 |
| 1981 | 0 | 0 |
| 1982 | 0 | 0 |
| 1983 | 3 | 0 |
| 1984 | 1 | 0 |
| 1985 | 2 | 0 |
| 1986 | 1 | 0 |
| 1987 | 1 | 0 |
| 1988 | 1 | 0 |
| 1989 | 0 | 0 |
| 1990 | 2 | 0 |
| 1991 | 1 | 0 |
| 1992 | 3 | 0 |
| 1993 | 1 | 0 |
| 1994 | 3 | 0 |
| 1995 | 3 | 0 |
| 1996 | 1 | 0 |
| 1997 | 3 | 0 |
| 1998 | 1 | 0 |
| 1999 | 9 | 0 |
| 2000 | 4 | 0 |
| 2001 | 3 | 1 |
| 2002 | 3 | 2 |
| 2003 | 2 | 4 |
| 2004 | 1 | 4 |
| 2005 | 5 | 4 |
| 2006 | 1 | 6 |
| 2007 | 3 | 6 |
| 2008 | 1 | 5 |
| 2009 | 1 | 5 |
| 2010 | 1 | 1 |
| 2011 | 9 | 2 |
| 2012 | 1 | 0 |
| 2013 | 1 | 1 |
| 2014 | 1 | 1 |
| 2015 | 1 | 3 |
| 2016 | 2 | 1 |
| 2017 | 1 | 2 |
| 2018 | 1 | 2 |
| 2019 | 2 | 2 |
| 2020 | 0 | 4 |
| 2021 | 1 | 1 |
| 2022 | 4 | 3 |
| 2023 | 1 | 1 |
| 2024 | 3 | 1 |
| 2025 | 1 | 0 |
By publication year. Applications have been published since 2001.
Subgroups
Granted patents
Recent patents
- Utility holder for a metal whiteboard15 Jul 2025US 12,358,318 B2Polyvision, Naamloze Vennootschap
- Portable dry erase board with carrying case30 Jul 2024US 12,049,100 B1
- Blackboard eraser cleaner9 Apr 2024US 11,951,765 B1Zhejiang University
- Automated whiteboard cleaning system30 Jan 2024US 11,887,361 B1King Faisal University
- System for coupling magnets to articles22 Aug 2023US 11,731,449 B2Amazing Magnets, LLC
- Blackboard eraser cleaner2 May 2024US 2024/0140131 A1Zhejiang University
- Reusable chalkboard kit18 May 2023US 2023/0150295 A1
- Utility holder for a metal whiteboard22 Sep 2022US 2022/0297470 A1Polyvision, Naamloze Vennootschap
- Writing implement holding eraser28 Jul 2022US 2022/0234381 A1
- Bigop learn and play, templates printed on each side of the dry erase board for learn and practice addition, subtraction and multiplication17 Mar 2022US 2022/0080768 A1Bigop Learn and Play LLC
Most cited
By later US patents