E21D 20/028
Devices or accesories for injecting a grouting liquid in a bore-hole
Official title: {Devices or accesories for injecting a grouting liquid in a bore-hole (E21D20/003 takes precedence; improving soil or rock by injections E21D9/001)}
E21D20/028 (Devices or accesories for injecting a grouting liquid in a bore-hole) appears on 81 US grants and 85 published applications in this corpus.
Search patents in E21D- Granted patents
- 81
- Published applications
- 85
- Assignees
- 63
- Inventors
- 196
- Latest grant
- 9 Jun 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 1 | 0 |
| 1977 | 0 | 0 |
| 1978 | 1 | 0 |
| 1979 | 0 | 0 |
| 1980 | 1 | 0 |
| 1981 | 0 | 0 |
| 1982 | 1 | 0 |
| 1983 | 0 | 0 |
| 1984 | 0 | 0 |
| 1985 | 0 | 0 |
| 1986 | 1 | 0 |
| 1987 | 4 | 0 |
| 1988 | 2 | 0 |
| 1989 | 0 | 0 |
| 1990 | 1 | 0 |
| 1991 | 0 | 0 |
| 1992 | 1 | 0 |
| 1993 | 0 | 0 |
| 1994 | 1 | 0 |
| 1995 | 0 | 0 |
| 1996 | 1 | 0 |
| 1997 | 0 | 0 |
| 1998 | 0 | 0 |
| 1999 | 1 | 0 |
| 2000 | 0 | 0 |
| 2001 | 1 | 0 |
| 2002 | 4 | 2 |
| 2003 | 0 | 1 |
| 2004 | 2 | 0 |
| 2005 | 0 | 1 |
| 2006 | 0 | 2 |
| 2007 | 1 | 4 |
| 2008 | 1 | 2 |
| 2009 | 2 | 4 |
| 2010 | 2 | 1 |
| 2011 | 1 | 5 |
| 2012 | 0 | 9 |
| 2013 | 1 | 3 |
| 2014 | 6 | 3 |
| 2015 | 5 | 4 |
| 2016 | 4 | 3 |
| 2017 | 0 | 4 |
| 2018 | 4 | 4 |
| 2019 | 6 | 6 |
| 2020 | 5 | 5 |
| 2021 | 3 | 5 |
| 2022 | 5 | 3 |
| 2023 | 3 | 4 |
| 2024 | 3 | 5 |
| 2025 | 4 | 3 |
| 2026 | 2 | 2 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Active control method and device for large deformation of deep thin-bedded surrounding rock9 Jun 2026US 12,650,076 B2Huaneng Lancang River Hydropower Inc.
- Drill head injection system for a self-drilling rock bolt assembly10 Mar 2026US 12,571,309 B2Oka Rock Bolt Technologies Pty Limited
- Injection driver assembly for hollow bar bolt installation14 Oct 2025US 12,442,299 B2Cementation USA Inc.
- Zonal bolt-grouting support device and method for cataclastic rock mass large deformation of high-stress tunnel2 Sep 2025US 12,404,772 B2Huaneng Lancang River Hydropower Inc.
- Hollow rod shear connector having static mixing system and method for setting a hollow rod shear connector in a rock layer5 Aug 2025US 12,378,885 B2Jmbg GmbH + Co KG
- Drill Head Injection System for a Self-Drilling Rock Bolt Assembly10 Sep 2026US 2026/0266179 A1Oka Rock Bolt Technologies Pty Limited
- Sealing device for positioning points in holes of process grouting28 May 2026US 2026/0146535 A1Anhui University of Science and Technology
- Bulk resin injection system27 Feb 2025US 2025/0067178 A1
- Grout plug with gasket for pocket former20 Feb 2025US 2025/0059890 A1
- Injection driver assembly for hollow bar bolt installation30 Jan 2025US 2025/0034997 A1Cementation USA Inc.
Most cited
By later US patents
- Automatic roof bolting system for mines43US 4,229,124 AJoy Manufacturing Company · 1980
- Resin nozzle positioner27US 6,447,210 B1Oldenburg Cannon, Inc. · 2002
- Clog-free inorganic grout emplacement gun16US 4,116,368 AThe United States of America as represented by the Secretary of the Interior · 1978
- Tubular anchor16US 6,457,910 B1Hilti Aktiengesellschaft · 2002
- Method and apparatus for insertion of rock bolts14US 6,793,445 B12004