Rotary machine and turbocharger
US-2025347295-A1 · Nov 13, 2025 · US
rotating diffusers
rotating diffusers · Cooperative Patent Classification (CPC)
Engines, pumps, lighting, heating, and mechanical systems.
Related technology areas
Mapped technology topics for this CPC code.
| Metric | Value |
|---|---|
| CPC code | F04D29/442 |
| Official title | {rotating diffusers} |
| Display label | rotating diffusers |
| Total patents | 61 |
Filing trend
Year-over-year patent counts classified under this CPC code.
Filing activity over the last five years is declining.
| Year | Patents |
|---|---|
| 2015 | 4 |
| 2016 | 4 |
| 2017 | 2 |
| 2018 | 6 |
| 2019 | 7 |
| 2020 | 7 |
| 2021 | 4 |
| 2022 | 13 |
| 2023 | 9 |
| 2024 | 2 |
| 2025 | 3 |
Representative patents
Representative publications under this CPC code from precomputed stats, or recent filings when stats are unavailable.
System and method for operation of variable geometry diffuser as check valve
US-12339047-B2 · Jun 24, 2025 · US
Axially nested compressors
US-12129859-B1 · Oct 29, 2024 · US
Variable geometry shrouded compressor/blower rotor design
US-11971050-B2 · Apr 30, 2024 · US
Variable geometry shrouded compressor/blower rotor design
US-2023417256-A1 · Dec 28, 2023 · US
Blowing device and combustion device including same
US-11795966-B2 · Oct 24, 2023 · US
Electric motor assembly for reducing air flow loss
US-11770043-B2 · Sep 26, 2023 · US
Straddled vehicle
US-11692558-B2 · Jul 4, 2023 · US
System and method for operation of variable geometry diffuser as check valve
US-2023147950-A1 · May 11, 2023 · US
Centrifugal compressor
US-2023079172-A1 · Mar 16, 2023 · US
Centrifugal compressor with recirculation structure
US-11603847-B2 · Mar 14, 2023 · US
Vaneless supersonic diffuser for compressor
US-11592034-B2 · Feb 28, 2023 · US
Mixed-flow compressor configuration for a refrigeration system
US-11585347-B2 · Feb 21, 2023 · US
Mixed-flow compressor with counter-rotating diffuser
US-11499569-B2 · Nov 15, 2022 · US
Fan and electromechanical apparatus
US-11486414-B2 · Nov 1, 2022 · US
Fluidic actuator for airfoil
US-11414177-B2 · Aug 16, 2022 · US
Straddled vehicle
US-2022205454-A1 · Jun 30, 2022 · US
Diffuser system and centrifugal compressor comprising the same
US-2022186744-A1 · Jun 16, 2022 · US
Rotating diffuser in centrifugal compressor
US-11346366-B2 · May 31, 2022 · US
Centrifugal compressor with recirculation structure
US-2022154721-A1 · May 19, 2022 · US
Frequently asked questions
Answers are generated from the same data shown on this page.
- What is CPC F04D29/442?
- CPC F04D29/442 is the Cooperative Patent Classification code for “rotating diffusers.”
- How many patents are filed under CPC F04D29/442 (rotating diffusers)?
- Our database includes 61 publications tagged with this CPC code.
- Is patent activity under CPC F04D29/442 growing?
- Publication counts under this code: 2 in 2024 vs 3 in 2025 (latest complete years).