F23N 3/04
Regulating air supply or draught: by operation of single valves or dampers
Official title: by operation of single valves or dampers by temperature sensitive elements
F23N3/04 (Regulating air supply or draught: by operation of single valves or dampers) appears on 112 US grants and 63 published applications in this corpus.
Search patents in F23N- Granted patents
- 112
- Published applications
- 63
- Assignees
- 67
- Inventors
- 172
- Latest grant
- 31 Mar 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 1 | 0 |
| 1977 | 4 | 0 |
| 1978 | 4 | 0 |
| 1979 | 6 | 0 |
| 1980 | 6 | 0 |
| 1981 | 8 | 0 |
| 1982 | 3 | 0 |
| 1983 | 7 | 0 |
| 1984 | 6 | 0 |
| 1985 | 5 | 0 |
| 1986 | 2 | 0 |
| 1987 | 1 | 0 |
| 1988 | 1 | 0 |
| 1989 | 2 | 0 |
| 1990 | 1 | 0 |
| 1991 | 1 | 0 |
| 1992 | 0 | 0 |
| 1993 | 1 | 0 |
| 1994 | 2 | 0 |
| 1995 | 2 | 0 |
| 1996 | 1 | 0 |
| 1997 | 1 | 0 |
| 1998 | 0 | 0 |
| 1999 | 0 | 0 |
| 2000 | 2 | 0 |
| 2001 | 0 | 0 |
| 2002 | 0 | 0 |
| 2003 | 2 | 2 |
| 2004 | 2 | 3 |
| 2005 | 0 | 1 |
| 2006 | 0 | 1 |
| 2007 | 0 | 1 |
| 2008 | 1 | 2 |
| 2009 | 0 | 2 |
| 2010 | 2 | 3 |
| 2011 | 1 | 5 |
| 2012 | 0 | 4 |
| 2013 | 0 | 2 |
| 2014 | 2 | 2 |
| 2015 | 2 | 3 |
| 2016 | 2 | 3 |
| 2017 | 3 | 6 |
| 2018 | 2 | 5 |
| 2019 | 7 | 4 |
| 2020 | 4 | 3 |
| 2021 | 4 | 3 |
| 2022 | 2 | 2 |
| 2023 | 2 | 2 |
| 2024 | 2 | 2 |
| 2025 | 3 | 1 |
| 2026 | 2 | 1 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Electronic closed-loop control device for fireplaces comprising a lower combustion system31 Mar 2026US 12,590,703 B2Maxitrol Company
- Gas heater17 Feb 2026US 12,553,620 B2Shinerich Industrial Ltd.
- Downward mobile gasification boiler for surface gas phase combustion and pyrolysis of biomass briquette11 Nov 2025US 12,467,620 B2Heilongjiang Zhongtan Jiahe Biomass Technology Research and Development Co.
- Apparatus for controlling an air inlet valve for a solid fuel burner2 Sep 2025US 12,405,008 B2Otter Controls Limited
- Frequency modulation auxiliary method and device for thermal power plant based on dual electric energy converter20 May 2025US 12,305,540 B1Yantai Power Plant of Huaneng Shandong Power Generation Co., Ltd.
- Electronic closed-loop control device for fireplaces comprising a lower combustion system23 Jul 2026US 2026/0210553 A1Maxitrol Company
- Combustion system with automated control of primary and secondary airflows2 Jan 2025US 2025/0003587 A1
- Electronic closed-loop control device for fireplaces comprising a lower combustion system5 Sep 2024US 2024/0295324 A1Maxitrol Company
- Gas heater8 Aug 2024US 2024/0263805 A1Shinerich Industrial Ltd.
- Downward mobile gasification boiler for surface gas phase combustion and pyrolysis of biomass briquette15 Jun 2023US 2023/0184424 A1Heilongjiang Zhongtan Jiahe Biomass Te Chnology Research and Development Co.
Most cited
By later US patents
- Furnace control using induced draft blower, exhaust gas flow rate sensing and density compensation55US 4,340,355 AHoneywell Inc. · 1982
- Vent control arrangement for combustion apparatus53US 4,284,235 A1981
- Shape memory actuator36US 4,979,672 AJohnson Service Company · 1990
- Automatic boiler damper31US 4,046,318 A1977
- Shape memory actuator smart connector30US 5,071,064 AJohnson Service Company · 1991