E21F 1/14
Air partitions
Official title: Air partitions; Air locks ({E21F1/003 takes precedence}; dams E21F17/103; air locks for foundations E02D)
E21F1/14 (Air partitions) appears on 58 US grants and 38 published applications in this corpus.
Search patents in E21F- Granted patents
- 58
- Published applications
- 38
- Assignees
- 32
- Inventors
- 86
- Latest grant
- 28 Oct 2025
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1979 | 3 | 0 |
| 1980 | 0 | 0 |
| 1981 | 1 | 0 |
| 1982 | 0 | 0 |
| 1983 | 1 | 0 |
| 1984 | 1 | 0 |
| 1985 | 3 | 0 |
| 1986 | 2 | 0 |
| 1987 | 1 | 0 |
| 1988 | 1 | 0 |
| 1989 | 0 | 0 |
| 1990 | 1 | 0 |
| 1991 | 0 | 0 |
| 1992 | 1 | 0 |
| 1993 | 0 | 0 |
| 1994 | 1 | 0 |
| 1995 | 3 | 0 |
| 1996 | 0 | 0 |
| 1997 | 1 | 0 |
| 1998 | 0 | 0 |
| 1999 | 1 | 0 |
| 2000 | 3 | 0 |
| 2001 | 2 | 0 |
| 2002 | 6 | 2 |
| 2003 | 1 | 3 |
| 2004 | 2 | 1 |
| 2005 | 0 | 0 |
| 2006 | 0 | 2 |
| 2007 | 2 | 3 |
| 2008 | 0 | 0 |
| 2009 | 0 | 1 |
| 2010 | 0 | 1 |
| 2011 | 0 | 0 |
| 2012 | 0 | 1 |
| 2013 | 1 | 0 |
| 2014 | 1 | 7 |
| 2015 | 3 | 3 |
| 2016 | 3 | 3 |
| 2017 | 2 | 1 |
| 2018 | 2 | 3 |
| 2019 | 2 | 1 |
| 2020 | 2 | 1 |
| 2021 | 1 | 1 |
| 2022 | 1 | 1 |
| 2023 | 1 | 2 |
| 2024 | 1 | 0 |
| 2025 | 1 | 1 |
By publication year. Applications have been published since 2001.
Subgroups
Granted patents
Recent patents
- System and method for sealing and pressurizing enclosed facilities via prefabricated modules, plugs, doors, and inserts28 Oct 2025US 12,455,092 B2
- Mining method without coal pillars with roof-cutting and roadway retaining17 Dec 2024US 12,168,931 B2China University of Mining and Technology, Beijing
- Split air cabin ventilation system for construction of tunnel inclined shaft and ventilation method using same13 Jun 2023US 11,674,392 B2Chang An University
- Sealing system5 Apr 2022US 11,293,285 B2The Secretary of State for Defence
- Blowing curtain face ventilation system for extended cut mining using passive regulator26 Jan 2021US 10,900,357 B2University of Kentucky Research Foundation
- Miner automated hardware installation system and automated brattice installer5 Jun 2025US 2025/0179917 A1The Mosaic Company
- Mining Method Without Coal Pillars With Roof-Cutting And Roadway Retaining17 Aug 2023US 2023/0258083 A1China University of Mining and Technology, Beijing
- System and method for sealing and pressurizing enclosed facilities via prefabricated modules, plugs, doors, and inserts.22 Jun 2023US 2023/0194118 A1
- Expandable mine stopping panel3 Mar 2022US 2022/0065109 A1
- Split air cabin ventilation system for construction of tunnel inclined shaft and ventilation method using same8 Jul 2021US 2021/0207481 A1Chang An University
Most cited
By later US patents
- Portable ventilation safety device48US 4,770,086 A1988
- Method and apparatus for supporting ventilation curtains in coal mines39US 5,308,280 ACurtain Buddy Corp. · 1994
- Mine ventilation structure24US 5,466,187 AJack Kennedy Metal Products & Buildings, Inc. · 1995
- Mine door power drive system22US 6,425,820 B1Jack Kennedy Metal Products & Buildings, Inc. · 2002
- Mine stopping21US 4,547,094 A1985