E21D 15/60
Devices for withdrawing props or chocks
E21D15/60 (Devices for withdrawing props or chocks) appears on 5 US grants and 5 published applications in this corpus.
Search patents in E21D- Granted patents
- 5
- Published applications
- 5
- Assignees
- 2
- Inventors
- 41
- Latest grant
- 21 Apr 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 2017 | 0 | 1 |
| 2018 | 1 | 0 |
| 2019 | 1 | 1 |
| 2020 | 1 | 2 |
| 2021 | 1 | 0 |
| 2022 | 0 | 0 |
| 2023 | 0 | 0 |
| 2024 | 0 | 1 |
| 2025 | 0 | 0 |
| 2026 | 1 | 0 |
By publication year. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Static crushing directional anchor withdrawal method at end of large-mining-height working face21 Apr 2026US 12,607,121 B2Huating Coal Group Co., Ltd.
- Base mechanism of single prop capable of being unloaded at reduced pressure19 Jan 2021US 10,895,154 B2China University of Mining and Technology
- Mechanical constant-resistance single prop continuous prop lifting pre-tightening device and method24 Nov 2020US 10,844,717 B2China University of Mining and Technology
- Process method for withdrawing and recovering mechanical constant-resistance single prop16 Jul 2019US 10,352,167 B2China University of Mining and Technology
- Method for removing hydraulic support for solid filling coal mining31 Jul 2018US 10,036,252 B2China University of Mining and Technology
- Static crushing directional anchor withdrawal method at end of large-mining-height working face7 Mar 2024US 2024/0076985 A1Huating Coal Group Co., Ltd.
- Base mechanism of single prop capable of being unloaded at reduced pressure24 Sep 2020US 2020/0300088 A1China University of Mining and Technology
- Mechanical constant-resistance single prop continuous prop lifting pre-tightening device and method30 Jul 2020US 2020/0240269 A1China University of Mining and Technology
- Process method for withdrawing and recovering mechanical constant-resistance single prop21 Mar 2019US 2019/0085691 A1China University of Mining and Technology
- Method for removing hydraulic support for solid filling coal mining18 May 2017US 2017/0138194 A1China University of Mining and Technology
Most cited
By later US patents