- All sections
- E - Fixed constructions
- E21D - Shaftstunnelsgallerieslarge underground chambers
- E21D 19/02 - Provisional protective covers for working space for use in longwall working
Patent holdings for IPC class E21D 19/02
Total number of patents in this class: 7
10-year publication summary
|
0
|
0
|
3
|
0
|
0
|
1
|
1
|
0
|
1
|
0
|
| 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
Principal owners for this class
| Owner |
All patents
|
This class
|
|---|---|---|
| Nordic Minesteel Technologies Inc. | 36 |
2 |
| Anhui University of Science and Technology | 188 |
1 |
| China University of Mining and Technology | 1266 |
1 |
| China University of Mining and Technology, Beijing | 95 |
1 |
| Swanson Industries, Inc. | 11 |
1 |
| Manchao He | 4 |
1 |
| Other owners | 0 |