Screw compressor, refrigeration system, and method for controlling refrigeration system
US-12297835-B2 · May 13, 2025 · US
Silencers using overlapping frequencies, e.g. Helmholtz resonators
Silencers using overlapping frequencies, e.g. Helmholtz resonators · 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 | F04C29/061 |
| Official title | {Silencers using overlapping frequencies, e.g. Helmholtz resonators} |
| Display label | Silencers using overlapping frequencies, e.g. Helmholtz resonators |
| Total patents | 52 |
Filing trend
Year-over-year patent counts classified under this CPC code.
Filing activity over the last five years is rapidly declining.
| Year | Patents |
|---|---|
| 2015 | 7 |
| 2016 | 5 |
| 2017 | 6 |
| 2018 | 6 |
| 2019 | 4 |
| 2020 | 6 |
| 2021 | 5 |
| 2022 | 5 |
| 2023 | 4 |
| 2024 | 3 |
| 2025 | 1 |
Representative patents
Representative publications under this CPC code from precomputed stats, or recent filings when stats are unavailable.
Compressor
US-12129854-B2 · Oct 29, 2024 · US
Compressor and electronic device using the same
US-12031540-B2 · Jul 9, 2024 · US
Screw compressor configured to compress a process gas and dampen pulsation waves
US-11920596-B2 · Mar 5, 2024 · US
Modular compressor discharge system
US-11732716-B2 · Aug 22, 2023 · US
Screw compressor
US-2023204034-A1 · Jun 29, 2023 · US
Screw compressor, refrigeration system, and method for controlling refrigeration system
US-2023138965-A1 · May 4, 2023 · US
Muffler for a compression mechanism of a rotary compressor
US-11585343-B2 · Feb 21, 2023 · US
Supercharger integral resonator
US-11339708-B2 · May 24, 2022 · US
Dual cylinder rotary compressor with intermediate plate that flows both cylinders to the muffler
US-11326605-B2 · May 10, 2022 · US
Vacuum pump having a silencer
US-2022128055-A1 · Apr 28, 2022 · US
Vacuum pump having a silencer
US-11274668-B2 · Mar 15, 2022 · US
Compressor
US-2022034324-A1 · Feb 3, 2022 · US
Compressor and electronic device using the same
US-2021363994-A1 · Nov 25, 2021 · US
Compressor
US-11136980-B2 · Oct 5, 2021 · US
Modular compressor discharge system
US-2021115926-A1 · Apr 22, 2021 · US
Rotary compressor
US-2021095671-A1 · Apr 1, 2021 · US
Gear pump and gear motor
US-2021079917-A1 · Mar 18, 2021 · US
Supercharger Integral Resonator
US-2020408139-A1 · Dec 31, 2020 · US
Compressor with pulsation attenuation space disposed in injection passage
US-10876532-B2 · Dec 29, 2020 · US
Frequently asked questions
Answers are generated from the same data shown on this page.
- What is CPC F04C29/061?
- CPC F04C29/061 is the Cooperative Patent Classification code for “Silencers using overlapping frequencies, e.g. Helmholtz resonators.”
- How many patents are filed under CPC F04C29/061 (Silencers using overlapping frequencies, e.g. Helmholtz resonators)?
- Our database includes 52 publications tagged with this CPC code.
- Is patent activity under CPC F04C29/061 growing?
- Publication counts under this code: 3 in 2024 vs 1 in 2025 (latest complete years).