- All sections
- C - Chemistry; metallurgy
- C21D - Modifying the physical structure of ferrous metals; general devices for heat treatment of ferrous or non-ferrous metals or alloys; making metal malleable, e.g. by decarburisation or tempering
- C21D 9/32 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for gear wheels, worm wheels, or the like
Patent holdings for IPC class C21D 9/32
Total number of patents in this class: 341
10-year publication summary
|
31
|
28
|
30
|
30
|
26
|
26
|
14
|
23
|
11
|
5
|
| 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 |
Principal owners for this class
| Owner |
All patents
|
This class
|
|---|---|---|
| Nippon Steel Corporation | 5649 |
39 |
| Nippon Steel & Sumitomo Metal Corporation | 1990 |
22 |
| Aisin AW Co., Ltd. | 2430 |
20 |
| JFE Steel Corporation | 6067 |
17 |
| Honda Motor Co., Ltd. | 24537 |
13 |
| Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) | 2865 |
11 |
| Dowa Thermotech Co., Ltd. | 41 |
10 |
| PARKER NETSUSHORI KOGYO Co., Ltd. | 33 |
6 |
| ZF Friedrichshafen AG | 6820 |
5 |
| NTN Corporation | 5008 |
5 |
| Komatsu Ltd. | 4265 |
5 |
| Daido Steel Co., Ltd. | 237 |
5 |
| Toyota Motor Corporation | 28582 |
4 |
| The Boeing Company | 19843 |
4 |
| Koyo Thermo Systems Co., Ltd. | 33 |
4 |
| SANYO Special Steel Co., Ltd. | 201 |
4 |
| Sikorsky Aircraft Corporation | 1150 |
4 |
| The Timken Company | 392 |
4 |
| ZF Wind Power Antwerpen N.V. | 165 |
4 |
| Sumitomo Electric Industries, Ltd. | 14131 |
3 |
| Other owners | 152 |