Layered structure of a flat, dimensionally stable building panel and a self-supporting air duct made of the layered structure
US-2026070300-A1 · Mar 12, 2026 · US
Multilayer duct
Multilayer duct · 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 | F24F13/0281 |
| Official title | {Multilayer duct} |
| Display label | Multilayer duct |
| Total patents | 26 |
Filing trend
Year-over-year patent counts classified under this CPC code.
Filing activity over the last five years is rapidly growing.
| Year | Patents |
|---|---|
| 2015 | 2 |
| 2017 | 3 |
| 2018 | 2 |
| 2019 | 3 |
| 2020 | 4 |
| 2021 | 1 |
| 2022 | 1 |
| 2023 | 4 |
| 2024 | 1 |
| 2025 | 4 |
| 2026 | 1 |
Representative patents
Representative publications under this CPC code from precomputed stats, or recent filings when stats are unavailable.
Self-muffling acoustic duct assembly for noise attenuation in a vehicle and method of using the same
US-2025251167-A1 · Aug 7, 2025 · US
Fire-rated ventilation duct and a method of manufacturing and/or installing such ventilation duct in a fire-rated ventilation duct structure penetration arrangement
US-2025189164-A1 · Jun 12, 2025 · US
Apparatus having a protective envelope, use thereof, and method for operating a room region
US-12320546-B2 · Jun 3, 2025 · US
Sound absorbing duct for environmental control system
US-12222128-B2 · Feb 11, 2025 · US
Air intake and exhaust assembly and packaged air conditioner
US-12007140-B2 · Jun 11, 2024 · US
Sound absorbing duct for environmental control system
US-2023358433-A1 · Nov 9, 2023 · US
Sound absorbing duct for environmental control system
US-11739973-B2 · Aug 29, 2023 · US
Collapsible coaxial flex duct
US-2023243549-A1 · Aug 3, 2023 · US
Apparatus having a protective envelope, use thereof, and method for operating a room region
US-2023093603-A1 · Mar 23, 2023 · US
Air intake and exhaust assembly and packaged air conditioner
US-2022307723-A1 · Sep 29, 2022 · US
3D printed continuous fiber reinforced part
US-11117362-B2 · Sep 14, 2021 · US
Composite duct with reinforcement
US-10823449-B2 · Nov 3, 2020 · US
Cover channel, cover frame, insulating panel, air handling unit and method for manufacturing a cover channel
US-10775072-B2 · Sep 15, 2020 · US
Laminar jackets for flexible ducts of hvac systems
US-2020256503-A1 · Aug 13, 2020 · US
Sound absorbing duct for environmental control system
US-2020056803-A1 · Feb 20, 2020 · US
Composite duct with reinforcement
US-2019376717-A1 · Dec 12, 2019 · US
Sound-damping air conduction part
US-10458675-B2 · Oct 29, 2019 · US
Cover channel, cover frame, insulating panel, air handling unit and method for manufacturing a cover channel
US-2019063781-A1 · Feb 28, 2019 · US
3d printed continuous fiber reinforced part
US-2018356118-A1 · Dec 13, 2018 · US
Frequently asked questions
Answers are generated from the same data shown on this page.
- What is CPC F24F13/0281?
- CPC F24F13/0281 is the Cooperative Patent Classification code for “Multilayer duct.”
- How many patents are filed under CPC F24F13/0281 (Multilayer duct)?
- Our database includes 26 publications tagged with this CPC code.
- Is patent activity under CPC F24F13/0281 growing?
- Publication counts under this code: 1 in 2024 vs 4 in 2025 (latest complete years).