- 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 9/40 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for bearing races
Patent holdings for IPC class C21D 9/40
Total number of patents in this class: 544
10-year publication summary
51
|
67
|
45
|
35
|
43
|
24
|
23
|
30
|
32
|
13
|
2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 |
Principal owners for this class
Owner |
All patents
|
This class
|
---|---|---|
NTN Corporation | 5008 |
154 |
Aktiebolaget SKF | 2700 |
42 |
Nippon Steel Corporation | 5649 |
22 |
JTEKT Corporation | 2423 |
20 |
NSK Ltd. | 2719 |
18 |
Schaeffler Technologies AG & Co. KG | 8880 |
17 |
Nippon Steel & Sumitomo Metal Corporation | 1990 |
10 |
Daido Steel Co., Ltd. | 237 |
8 |
Neturen Co., Ltd. | 193 |
8 |
Honda Motor Co., Ltd. | 24537 |
7 |
Toyota Motor Corporation | 28582 |
7 |
Inductoheat, Inc. | 48 |
7 |
JFE Steel Corporation | 6067 |
7 |
Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) | 2865 |
6 |
ThyssenKrupp Rothe Erde GmbH | 66 |
6 |
Robert Bosch GmbH | 40953 |
5 |
Aisin AW Co., Ltd. | 2430 |
5 |
ArcelorMittal | 1887 |
5 |
Rothe Erde GmbH | 19 |
5 |
Schaeffler KG | 960 |
5 |
Other owners | 180 |