E21D 15/55
Of prop heads or feet
Official title: of prop heads {or feet}
E21D15/55 (Of prop heads or feet) appears on 12 US grants and 9 published applications in this corpus.
Search patents in E21D- Granted patents
- 12
- Published applications
- 9
- Assignees
- 12
- Inventors
- 42
- Latest grant
- 19 Jan 2021
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1992 | 1 | 0 |
| 1993 | 0 | 0 |
| 1994 | 2 | 0 |
| 1995 | 0 | 0 |
| 1996 | 0 | 0 |
| 1997 | 1 | 0 |
| 1998 | 0 | 0 |
| 1999 | 0 | 0 |
| 2000 | 0 | 0 |
| 2001 | 0 | 1 |
| 2002 | 1 | 0 |
| 2003 | 0 | 0 |
| 2004 | 0 | 1 |
| 2005 | 1 | 0 |
| 2006 | 0 | 0 |
| 2007 | 0 | 0 |
| 2008 | 0 | 1 |
| 2009 | 0 | 0 |
| 2010 | 0 | 0 |
| 2011 | 1 | 0 |
| 2012 | 0 | 1 |
| 2013 | 0 | 0 |
| 2014 | 0 | 1 |
| 2015 | 0 | 1 |
| 2016 | 1 | 0 |
| 2017 | 0 | 1 |
| 2018 | 2 | 0 |
| 2019 | 0 | 0 |
| 2020 | 1 | 1 |
| 2021 | 1 | 0 |
| 2022 | 0 | 0 |
| 2023 | 0 | 0 |
| 2024 | 0 | 1 |
By publication year. Applications have been published since 2001.
Recent patents
- Base mechanism of single prop capable of being unloaded at reduced pressure19 Jan 2021US 10,895,154 B2China University of Mining and Technology
- Apparatus for protecting roof tray when gob-side entry retaining end support migrates3 Nov 2020US 10,822,949 B1China Mining & Civil New Material Science and Technology Ltd.
- Adapter for a formwork support structure6 Nov 2018US 10,119,282 B2Form 700 Pty Ltd
- Yieldable prop with yieldable insert12 Jun 2018US 9,995,140 B2FCI Holdings Delaware, Inc.
- Prop head bearing device for shield supports4 Oct 2016US 9,458,716 B2Caterpillar Global Mining Europe GmbH
- Improved prop assemblies25 Jul 2024US 2024/0247506 A1R.J. Goldspink Pty Limited
- Base mechanism of single prop capable of being unloaded at reduced pressure24 Sep 2020US 2020/0300088 A1China University of Mining and Technology
- An adapter for a formwork support structure9 Mar 2017US 2017/0067263 A1Form 700 Pty Ltd
- Yieldable Prop with Yieldable Insert28 May 2015US 2015/0147122 A1FCI Holdings Delaware, Inc.
- Prop head bearing device for shield supports25 Sep 2014US 2014/0286713 A1Caterpillar Global Mining Europe GmbH
Most cited
By later US patents
- Mine prop9US 6,910,834 B2Burrell Mining Products, Inc. · 2005
- Mine support having a linearly moveable and/or pivoting end plate8US 8,052,352 B2FCI Holdings Delaware, Inc. · 2011
- Prop preloading apparatus7US 5,149,228 AHL&H Timber Products (Proprietary) Limited · 1992
- Compressible support column7US 6,499,916 B2American Commercial, Incorporated · 2002
- Prop headboard6US 5,658,099 AHL & H Timber Products (Propreitary) Limited · 1997