E21C 27/20
Mineral freed by means not involving slitting
E21C27/20 (Mineral freed by means not involving slitting) appears on 475 US grants and 294 published applications in this corpus.
Search patents in E21C- Granted patents
- 475
- Published applications
- 294
- Assignees
- 174
- Inventors
- 718
- Latest grant
- 25 Aug 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 15 | 0 |
| 1977 | 23 | 0 |
| 1978 | 22 | 0 |
| 1979 | 13 | 0 |
| 1980 | 21 | 0 |
| 1981 | 15 | 0 |
| 1982 | 11 | 0 |
| 1983 | 11 | 0 |
| 1984 | 12 | 0 |
| 1985 | 9 | 0 |
| 1986 | 4 | 0 |
| 1987 | 11 | 0 |
| 1988 | 8 | 0 |
| 1989 | 7 | 0 |
| 1990 | 3 | 0 |
| 1991 | 2 | 0 |
| 1992 | 8 | 0 |
| 1993 | 7 | 0 |
| 1994 | 4 | 0 |
| 1995 | 2 | 0 |
| 1996 | 4 | 0 |
| 1997 | 6 | 0 |
| 1998 | 8 | 0 |
| 1999 | 8 | 0 |
| 2000 | 3 | 0 |
| 2001 | 9 | 1 |
| 2002 | 1 | 3 |
| 2003 | 3 | 1 |
| 2004 | 2 | 5 |
| 2005 | 2 | 7 |
| 2006 | 3 | 4 |
| 2007 | 4 | 10 |
| 2008 | 7 | 7 |
| 2009 | 4 | 6 |
| 2010 | 8 | 17 |
| 2011 | 7 | 11 |
| 2012 | 7 | 15 |
| 2013 | 10 | 17 |
| 2014 | 18 | 28 |
| 2015 | 24 | 27 |
| 2016 | 16 | 19 |
| 2017 | 15 | 31 |
| 2018 | 15 | 27 |
| 2019 | 25 | 8 |
| 2020 | 20 | 14 |
| 2021 | 8 | 11 |
| 2022 | 8 | 5 |
| 2023 | 8 | 7 |
| 2024 | 7 | 4 |
| 2025 | 3 | 5 |
| 2026 | 4 | 4 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
- E21C 27/24By milling means acting on the full working face , i.e. the240
- E21C 27/32By adjustable or non-adjustable planing means with or without loading arrangements102
- E21C 27/22By rotary drills with breaking-down means65
- E21C 27/30By jaws, buckets or scoops that scoop-out the mineral37
- E21C 27/28By percussive drills with breaking-down means26
- E21C 27/46By percussed planing means4
- E21C 27/26By closely adjacent cutter chains acting on the full working face1
Recent patents
- High power laser tunneling mining and construction equipment and methods of use25 Aug 2026US 12,715,063 B2Foro Energy, Inc.
- Mining vehicle for cobalt-rich crust from the seabed11 Aug 2026US 12,704,066 B2Qingdao University of Science and Technology
- Device for milling in particular rock and other materials2 Jun 2026US 12,644,383 B2CONTEC—Maschinenbau—& Entwicklungstechnik GmbH
- Tunnel tunneling system3 Mar 2026US 12,565,837 B2Ccteg Taiyuan Research Institute
- Cutting apparatus4 Nov 2025US 12,460,545 B2Sandvik Mining and Construction Oy
- Underground mining system and method30 Jul 2026US 2026/0218612 A1
- Method for controlling automatic operation of mining electric shovel considering sudden load variations during excavations2 Jul 2026US 2026/0185445 A1China University of Mining and Technology
- Integrated rapid excavation equipment for rock roadways and method thereof28 May 2026US 2026/0146533 A1China University of Mining and Technology
- Method and material removal system14 May 2026US 2026/0132715 A1Rockfeel GmbH
- Roadheader and cutter head therefor9 Oct 2025US 2025/0314172 A1Sandvik Mining and Construction Oy
Most cited
By later US patents
- Apparatus and method for continuous mining45US 5,112,111 AAddington Resources, Inc. · 1992
- Rolling assembly and pick assembly mounted on a trencher44US 7,681,338 B22010
- Mining machine with driven disc cutters44US 7,934,776 B2Joy MM Delaware, Inc. · 2011
- Method and apparatus for a rotating cutting drum or arm mounted with paired opposite circular polarity antennas and resonant microstrip patch transceiver for measuring coal, trona and potash layers forward, side and around a continuous mining machine43US 5,769,503 AStolar, Inc. · 1998
- Remote controlled high wall coal mining system41US 4,323,280 ACoalex, Inc. · 1982