E21D 21/0026
Anchoring-bolts for roof, floor in galleries or longwall working, or shaft-lining protection
Official title: {characterised by constructional features of the bolts}
E21D21/0026 (Anchoring-bolts for roof, floor in galleries or longwall working, or shaft-lining protection) appears on 452 US grants and 352 published applications in this corpus.
Search patents in E21D- Granted patents
- 452
- Published applications
- 352
- Assignees
- 238
- Inventors
- 759
- Latest grant
- 18 Aug 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 3 | 0 |
| 1977 | 5 | 0 |
| 1978 | 5 | 0 |
| 1979 | 4 | 0 |
| 1980 | 5 | 0 |
| 1981 | 11 | 0 |
| 1982 | 15 | 0 |
| 1983 | 5 | 0 |
| 1984 | 10 | 0 |
| 1985 | 8 | 0 |
| 1986 | 8 | 0 |
| 1987 | 18 | 0 |
| 1988 | 5 | 0 |
| 1989 | 6 | 0 |
| 1990 | 7 | 0 |
| 1991 | 8 | 0 |
| 1992 | 3 | 0 |
| 1993 | 6 | 0 |
| 1994 | 8 | 0 |
| 1995 | 10 | 0 |
| 1996 | 9 | 0 |
| 1997 | 9 | 0 |
| 1998 | 15 | 0 |
| 1999 | 7 | 0 |
| 2000 | 7 | 0 |
| 2001 | 7 | 6 |
| 2002 | 9 | 5 |
| 2003 | 9 | 7 |
| 2004 | 6 | 14 |
| 2005 | 6 | 11 |
| 2006 | 14 | 12 |
| 2007 | 2 | 19 |
| 2008 | 10 | 15 |
| 2009 | 5 | 17 |
| 2010 | 6 | 16 |
| 2011 | 13 | 20 |
| 2012 | 11 | 21 |
| 2013 | 9 | 13 |
| 2014 | 19 | 12 |
| 2015 | 8 | 17 |
| 2016 | 8 | 9 |
| 2017 | 8 | 9 |
| 2018 | 9 | 19 |
| 2019 | 17 | 14 |
| 2020 | 15 | 23 |
| 2021 | 13 | 17 |
| 2022 | 15 | 8 |
| 2023 | 7 | 13 |
| 2024 | 12 | 17 |
| 2025 | 7 | 8 |
| 2026 | 10 | 10 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
- E21D 21/006Anchoring-bolts made of cables or wires122
- E21D 21/0033Having a jacket or outer tube119
- E21D 21/004Bolts held in the borehole by friction all along their length, without84
- E21D 21/0053Anchoring-bolts in the form of lost drilling rods66
- E21D 21/0046Formed by a plurality of elements arranged longitudinally50
- E21D 21/0073Anchoring-bolts having an inflatable sleeve26
- E21D 21/0066Anchoring-bolts formed by a bundle of radially arranged rigid elements13
Recent patents
- Drilling and bolting tool18 Aug 2026US 12,709,981 B2Joy Global Underground Mining LLC
- Deformable anchor cable28 Jul 2026US 12,692,791 B2Fuzhou University
- Tunnel constraint anchor cable and method for improving stability of initial support structure14 Jul 2026US 12,680,451 B2Chang An University
- Active control method and device for large deformation of deep thin-bedded surrounding rock9 Jun 2026US 12,650,076 B2Huaneng Lancang River Hydropower Inc.
- Rock bolt28 Apr 2026US 12,612,861 B2Sandvik Mining and Construction Australia (Production/Supply) Pty Ltd
- Dynamic rock bolt assembly8 Oct 2026US 2026/0309029 A1Geomechanical Services and Innovations Inc.
- Rock bolt17 Sep 2026US 2026/0275866 A1Sandvik Mining and Construction Australia (Production/Supply) Pty Ltd
- Drill Head Injection System for a Self-Drilling Rock Bolt Assembly10 Sep 2026US 2026/0266179 A1Oka Rock Bolt Technologies Pty Limited
- Rock bolt13 Aug 2026US 2026/0235029 A1Sandvik Mining and Construction Australia (Production/Supply) Pty Ltd
- Geothermal-based self-compensating expansion shell rock bolt13 Aug 2026US 2026/0235030 A1China University of Geosciences (Wuhan)
Most cited
By later US patents
- Method of rock bolting and rock bolt122US 4,511,289 AAtlas Copco Aktiebolag · 1985
- Method and installation apparatus for rock bolting121US 4,423,986 AAtlas Copco Aktiebolag · 1984
- Method of rock bolting and tube-formed expansion bolt114US 4,634,317 AAtlas Copco Aktiebolag · 1987
- Rock bolt system and method of rock bolting108US 5,335,736 ACommonwealth Scientific and Industrial Research Organisation · 1994
- Anchored cable sling system90US 5,584,608 A1996