Machine component
US-2021032737-A1 · Feb 4, 2021 · US
for plain shafts
for plain shafts · Cooperative Patent Classification (CPC)
Chemical and metallurgical processes, compounds, and materials.
Related technology areas
Mapped technology topics for this CPC code.
| Metric | Value |
|---|---|
| CPC code | C21D9/28 |
| Official title | for plain shafts |
| Display label | for plain shafts |
| Total patents | 110 |
Filing trend
Year-over-year patent counts classified under this CPC code.
Filing activity over the last five years is stable.
| Year | Patents |
|---|---|
| 2015 | 7 |
| 2016 | 11 |
| 2017 | 9 |
| 2018 | 10 |
| 2019 | 12 |
| 2020 | 9 |
| 2021 | 11 |
| 2022 | 12 |
| 2023 | 4 |
| 2024 | 10 |
| 2025 | 13 |
| 2026 | 2 |
Representative patents
Representative publications under this CPC code from precomputed stats, or recent filings when stats are unavailable.
Methods of modifying material properties of workpieces using high-pressure-torsion apparatuses
US-10907226-B2 · Feb 2, 2021 · US
Heat treatment method of rod-shape workpiece
US-10844447-B2 · Nov 24, 2020 · US
Drive shaft and method for producing drive shaft
US-2020307312-A1 · Oct 1, 2020 · US
Method for preventing cracking along the surface at the inner hole of a hollow shaft during horizontal water quenching
US-2020283865-A1 · Sep 10, 2020 · US
High-pressure-torsion apparatuses and methods of modifying material properties of workpieces using such apparatuses
US-2020199699-A1 · Jun 25, 2020 · US
High-pressure-torsion apparatuses and methods of modifying material properties of workpieces using such apparatuses
US-2020199701-A1 · Jun 25, 2020 · US
High-pressure-torsion apparatuses and methods of modifying material properties of workpieces using such apparatuses
US-2020199700-A1 · Jun 25, 2020 · US
Carburized shaft part
US-2020182286-A1 · Jun 11, 2020 · US
Steel, carburized steel component, and method for manufacturing carburized steel component
US-10597765-B2 · Mar 24, 2020 · US
Method for manufacturing shaft body
US-10590508-B2 · Mar 17, 2020 · US
Carburized component
US-10428414-B2 · Oct 1, 2019 · US
Systems and methods for improving backward flow forming of shafts
US-2019291167-A1 · Sep 26, 2019 · US
Tooling for stress relieving a turbine wheel and shaft
US-10422016-B2 · Sep 24, 2019 · US
Steel for cold forging and manufacturing method thereof
US-2019264305-A1 · Aug 29, 2019 · US
Rail vehicle axle
US-10392683-B2 · Aug 27, 2019 · US
Heat treatment method of rod-shape workpiece
US-2019241986-A1 · Aug 8, 2019 · US
Laser heat-treated shaft and method of making the same
US-2019218634-A1 · Jul 18, 2019 · US
Method for manufacturing a spherical-cap-shaped recess in a drive shaft, drive shaft comprising the recess, and hydrostatic axial piston machine comprising the drive shaft
US-10302072-B2 · May 28, 2019 · US
Method of treating a steel
US-2019112680-A1 · Apr 18, 2019 · US
Frequently asked questions
Answers are generated from the same data shown on this page.
- What is CPC C21D9/28?
- CPC C21D9/28 is the Cooperative Patent Classification code for “for plain shafts.”
- How many patents are filed under CPC C21D9/28 (for plain shafts)?
- Our database includes 110 publications tagged with this CPC code.
- Is patent activity under CPC C21D9/28 growing?
- Publication counts under this code: 10 in 2024 vs 13 in 2025 (latest complete years).