E21D 15/52
Extensible units located above or below standard props
Official title: Extensible units located above or below standard props (for allowing step-by-step movement of cap E21D23/06; setting props or chocks E21D15/58)
E21D15/52 (Extensible units located above or below standard props) appears on 2 US grants and 6 published applications in this corpus.
Search patents in E21D- Granted patents
- 2
- Published applications
- 6
- Assignees
- 2
- Inventors
- 13
- Latest grant
- 8 Feb 2022
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 2006 | 0 | 1 |
| 2007 | 0 | 0 |
| 2008 | 0 | 1 |
| 2009 | 0 | 0 |
| 2010 | 0 | 0 |
| 2011 | 1 | 0 |
| 2012 | 0 | 1 |
| 2013 | 0 | 0 |
| 2014 | 0 | 0 |
| 2015 | 0 | 1 |
| 2016 | 0 | 0 |
| 2017 | 0 | 1 |
| 2018 | 0 | 0 |
| 2019 | 0 | 0 |
| 2020 | 0 | 0 |
| 2021 | 0 | 1 |
| 2022 | 1 | 0 |
By publication year.
Subgroups
Granted patents
Recent patents
- Adjustable Lattice Girder27 May 2021US 2021/0156251 A1FCI Holdings Delaware, Inc.
- Telescopic mine roof support11 May 2017US 2017/0130580 A1
- Telescopic mine roof support2 Jul 2015US 2015/0184512 A1Burrell Mining Products, Inc.
- Mine Support Having a Linearly Moveable and/or Pivoting End Plate2 Feb 2012US 2012/0027529 A1FCI Holdings Delaware, Inc.
- Mine support having a linearly moveable and/or pivoting end plate2 Oct 2008US 2008/0240868 A1FCI Holdings Delaware, Inc.
Most cited
By later US patents