- All sections
- C - Chemistrymetallurgy
- C21D - Modifying the physical structure of ferrous metalsgeneral devices for heat treatment of ferrous or non-ferrous metals or alloysmaking metal malleable, e.g. by decarburisation or tempering
- C21D 9/40 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articlesFurnaces therefor for ringsHeat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articlesFurnaces therefor for bearing races
Patent holdings for IPC class C21D 9/40
Total number of patents in this class: 536
10-year publication summary
67
|
45
|
35
|
43
|
24
|
23
|
33
|
32
|
25
|
5
|
2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
Principal owners for this class
Owner |
All patents
|
This class
|
---|---|---|
NTN Corporation | 4983 |
156 |
Aktiebolaget SKF | 2937 |
41 |
JTEKT Corporation | 2492 |
21 |
NSK Ltd. | 2770 |
21 |
Nippon Steel Corporation | 6207 |
20 |
Schaeffler Technologies AG & Co. KG | 9818 |
18 |
Nippon Steel & Sumitomo Metal Corporation | 1988 |
10 |
Daido Steel Co., Ltd. | 269 |
8 |
Neturen Co., Ltd. | 198 |
8 |
Inductoheat, Inc. | 49 |
7 |
Honda Motor Co., Ltd. | 25174 |
6 |
Toyota Motor Corporation | 31819 |
6 |
JFE Steel Corporation | 6816 |
6 |
Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) | 2876 |
6 |
ThyssenKrupp Rothe Erde GmbH | 66 |
6 |
Robert Bosch GmbH | 42632 |
5 |
ArcelorMittal | 2272 |
5 |
MAHLE International GmbH | 2761 |
5 |
SMS Elotherm GmbH | 14 |
5 |
TOYOTA JIDOSHA KABUSHIKI KAISHA (also trading as TOYOTA MOTOR CORPORATION) | 12821 |
5 |
Other owners | 171 |