E21D 23/04
Structural features of the supporting construction
Official title: Structural features of the supporting construction, e.g. linking members between adjacent frames or sets of props; Means for counteracting lateral sliding on inclined floor (E21D23/14 takes precedence)
E21D23/04 (Structural features of the supporting construction) appears on 215 US grants and 49 published applications in this corpus.
Search patents in E21D- Granted patents
- 215
- Published applications
- 49
- Assignees
- 90
- Inventors
- 386
- Latest grant
- 28 Jul 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 13 | 0 |
| 1977 | 15 | 0 |
| 1978 | 22 | 0 |
| 1979 | 5 | 0 |
| 1980 | 13 | 0 |
| 1981 | 12 | 0 |
| 1982 | 10 | 0 |
| 1983 | 11 | 0 |
| 1984 | 13 | 0 |
| 1985 | 11 | 0 |
| 1986 | 8 | 0 |
| 1987 | 2 | 0 |
| 1988 | 8 | 0 |
| 1989 | 5 | 0 |
| 1990 | 4 | 0 |
| 1991 | 3 | 0 |
| 1992 | 3 | 0 |
| 1993 | 3 | 0 |
| 1994 | 0 | 0 |
| 1995 | 1 | 0 |
| 1996 | 1 | 0 |
| 1997 | 2 | 0 |
| 1998 | 1 | 0 |
| 1999 | 1 | 0 |
| 2000 | 0 | 0 |
| 2001 | 0 | 0 |
| 2002 | 0 | 1 |
| 2003 | 0 | 1 |
| 2004 | 1 | 2 |
| 2005 | 1 | 0 |
| 2006 | 1 | 1 |
| 2007 | 2 | 1 |
| 2008 | 0 | 0 |
| 2009 | 1 | 0 |
| 2010 | 0 | 0 |
| 2011 | 0 | 2 |
| 2012 | 1 | 3 |
| 2013 | 1 | 1 |
| 2014 | 1 | 1 |
| 2015 | 2 | 1 |
| 2016 | 3 | 3 |
| 2017 | 2 | 7 |
| 2018 | 4 | 5 |
| 2019 | 6 | 3 |
| 2020 | 5 | 4 |
| 2021 | 4 | 3 |
| 2022 | 2 | 0 |
| 2023 | 1 | 5 |
| 2024 | 4 | 2 |
| 2025 | 4 | 3 |
| 2026 | 2 | 0 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
- E21D 23/06Special mine caps or special tops of pit-props for permitting step-by-step movement72
- E21D 23/0427Shield operating devices32
- E21D 23/0409Aligning or guiding means for the supports or for the constitutive parts18
- E21D 23/0436Means for inclining the base member of the support17
- E21D 23/0481Supports specially adapted for use in combination with the placing of filling-up17
- E21D 23/0454Trailing plates14
- E21D 23/0418Positioning devices and stabilizing means for the props9
- E21D 23/0472Supports specially adapted for people walking or transporting material6
Recent patents
- Tunneling system28 Jul 2026US 12,692,790 B2Ccteg Taiyuan Research Institute
- Asymmetric hydraulic supports for pseudo inclined mining in steeply dipping seam13 Jan 2026US 12,523,151 B2XI'AN UNIVERSITY OF SCIENCE AND TECHNOLOGY Xi'an, China
- Coal-based solid waste transport and filling integrated machine mining system and method11 Nov 2025US 12,467,362 B2Anhui University of Science and Technology
- External fluid bar for fluid driven cylinder4 Nov 2025US 12,460,546 B1
- Hydraulic support with quick response function for coal wall spalling8 Jul 2025US 12,352,169 B2Shandong University of Science and Technology
- Roof Support Unit for a Mining Machine22 May 2025US 2025/0163807 A1Caterpillar Inc.
- Asymmetric hydraulic supports for pseudo inclined mining in steeply dipping seam10 Apr 2025US 2025/0116192 A1Xi'an University of Science and Technology
- Ventilation method for high gas working face based on alternating intake and air return in mine gallery2 Jan 2025US 2025/0003337 A1Taiyuan University of Technology
- Tunneling System25 Jul 2024US 2024/0247551 A1Ccteg Taiyuan Research Institute
- Hydraulic Support with Quick Response Function for Coal Wall Spalling25 Jan 2024US 2024/0026788 A1Shandong University of Science and Technology
Most cited
By later US patents
- Mine roof support assembly20US 4,217,067 AGewerkschaft Eisenhutte Westfalia · 1980
- Mining method and apparatus15US 4,102,550 APeabody Coal Company · 1978
- Mine roof support14US 4,010,618 ADowty Mining Equipment Limited · 1977
- Method and apparatus for supporting the roof of an underground mine working14US 4,099,785 A1978
- Prop head bearing14US 7,201,541 B2DBT GmbH · 2007