E21F
Safety devices, transport, filling-up, rescue, ventilation, or draining in or of mines
Official title: Safety devices, transport, filling-up, rescue, ventilation, or draining in or of mines or tunnels
E21F (Safety devices, transport, filling-up, rescue, ventilation, or draining in or of mines) appears on 1,550 US grants and 1,207 published applications in this corpus.
Search patents in E21F- Granted patents
- 1,550
- Published applications
- 1,207
- Assignees
- 862
- Inventors
- 3,685
- Latest grant
- 22 Sep 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 39 | 0 |
| 1977 | 37 | 0 |
| 1978 | 50 | 0 |
| 1979 | 43 | 0 |
| 1980 | 27 | 0 |
| 1981 | 52 | 0 |
| 1982 | 38 | 0 |
| 1983 | 30 | 0 |
| 1984 | 38 | 0 |
| 1985 | 27 | 0 |
| 1986 | 17 | 0 |
| 1987 | 21 | 0 |
| 1988 | 17 | 0 |
| 1989 | 19 | 0 |
| 1990 | 14 | 0 |
| 1991 | 12 | 0 |
| 1992 | 20 | 0 |
| 1993 | 16 | 0 |
| 1994 | 7 | 0 |
| 1995 | 15 | 0 |
| 1996 | 9 | 0 |
| 1997 | 6 | 0 |
| 1998 | 14 | 0 |
| 1999 | 19 | 0 |
| 2000 | 11 | 0 |
| 2001 | 22 | 5 |
| 2002 | 28 | 17 |
| 2003 | 20 | 17 |
| 2004 | 18 | 28 |
| 2005 | 12 | 17 |
| 2006 | 6 | 10 |
| 2007 | 11 | 25 |
| 2008 | 10 | 35 |
| 2009 | 8 | 20 |
| 2010 | 19 | 30 |
| 2011 | 17 | 38 |
| 2012 | 23 | 51 |
| 2013 | 40 | 64 |
| 2014 | 49 | 72 |
| 2015 | 48 | 66 |
| 2016 | 50 | 73 |
| 2017 | 76 | 94 |
| 2018 | 64 | 61 |
| 2019 | 79 | 61 |
| 2020 | 59 | 76 |
| 2021 | 57 | 74 |
| 2022 | 43 | 55 |
| 2023 | 46 | 48 |
| 2024 | 74 | 69 |
| 2025 | 43 | 52 |
| 2026 | 30 | 49 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Main groups
Granted patents with any code in the group
- E21F 17/00Methods or devices for use in mines or tunnels, not covered elsewhere500
- E21F 13/00Transport specially adapted to underground conditions476
- E21F 1/00Ventilation of mines or tunnels171
- E21F 5/00Means or methods for preventing, binding, depositing, or removing dust159
- E21F 15/00Methods or devices for placing filling-up materials in underground workings147
- E21F 7/00Methods or devices for drawing- off gases with or without subsequent use123
- E21F 11/00Rescue devices or other safety devices63
- E21F 16/00Drainage34
All 10 main groupsShow fewer
Recent patents
- Method for coal seam gas seepage displacement, seepage water locking and dust reduction22 Sep 2026US 12,742,389 B2Hunan University of Science and Technology
- Autonomous mining vehicle control1 Sep 2026US 12,723,511 B2Sandvik Mining and Construction Oy
- Mining system with a flexible conveyor system1 Sep 2026US 12,723,512 B2Underground Extraction Technologies Pty LTD
- Towing arrangement of a battery-powered mining machine and a battery-powered mining machine25 Aug 2026US 12,715,254 B2Sandvik Mining and Construction Oy
- System and method for controlling roof support18 Aug 2026US 12,709,982 B2Joy Global Underground Mining LLC
- Steep-angle thermoplastic elastomer belts and belts made from a combination of a rubber and thermoplastic elastomers with thermoplastic abrasive and impact resistant chevron cleats for mining and heavy industrial applications1 Oct 2026US 2026/0296792 A1ContiTech Deutschland GmbH
- Method and system for predicting blasting vibration inside surrounding rocks in deep buried tunnels1 Oct 2026US 2026/0298084 A1Northeastern University
- Gas extraction method and system based on non-solidifying sealing material1 Oct 2026US 2026/0298089 A1Taiyuan University of Technology
- Monorail installation device1 Oct 2026US 2026/0298090 A1Sandvik Mining and Construction Oy
- Energy-saving and environment-friendly intelligent thermal insulation air chamber for tunnels in cold regions and setting method thereof10 Sep 2026US 2026/0266180 A1Southwest Jiaotong University
Most cited
By later US patents
- Upgrading and mining of coal308US 6,969,123 B2Shell Oil Company · 2005
- Coal gasification method288US 4,243,101 A1981
- Personnel monitoring and locating system218US 4,495,496 AJohnson Engineering Corporation · 1985
- Minimizing subsidence effects during production of coal in situ145US 4,463,807 AIn Situ Technology, Inc. · 1984
- Minimizing subsidence effects during production of coal in situ144US 4,448,252 AIn Situ Technology, Inc. · 1984