F23K FEEDING FUEL TO COMBUSTION APPARATUS
Introduced: September 1968
Classification Context
- Section:
- MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- Class:
- COMBUSTION APPARATUS; COMBUSTION PROCESSES
- Subclass:
- FEEDING FUEL TO COMBUSTION APPARATUS
Description
F23K covers fuel supply systems and mechanisms for delivering solid, liquid, or gaseous fuels into combustion chambers of furnaces, boilers, engines, and similar equipment. This subclass includes fuel feeding devices such as injectors, burners, stokers, and fuel metering systems, as well as related control and regulation mechanisms for managing fuel flow rates and distribution. The classification excludes fuel preparation and treatment processes (covered under F23D) and focuses specifically on the mechanical and functional aspects of fuel introduction into the combustion zone.
Filing statistics
IPC subclass F23K recorded 17,228 patent applications worldwide between 2013 and 2023. Annual filings grew from 1,169 in 2013 to 1,709 in 2023 (+46%), peaking at 2,026 applications in 2020. The most active applicants in class F23 are GE (GENERAL ELECTRIC COMPANY) (2,124 applications), XIAN THERMAL POWER RESEARCH INSTITUTE COMPANY (1,369 applications) and NINGBO FOTILE KITCHENWARE COMPANY (1,363 applications).
Source: EPO PATSTAT, worldwide filings
In class comparison
F23K ranks 7th of 12 subclasses with filings in F23, with 17,228 applications between 2013 and 2023, 5.7% of the class. Annual filings grew 46% from 2013 to 2023, below the class as a whole (+76%).
| Rank | Subclass | Title | Applications | Share |
|---|---|---|---|---|
| 1 | F23J, Removal or Treatment of Combustion Products or Combustion Residues; Flues | Removal or Treatment of Combustion Products or Combustion Residues; Flues | 62,845 | 20.9% |
| 2 | F23G, Cremation Furnaces; Consuming Waste or Low Grade Fuels by Combustion | Cremation Furnaces; Consuming Waste or Low Grade Fuels by Combustion | 62,605 | 20.8% |
| 3 | F23D, Burners | Burners | 48,008 | 15.9% |
| 4 | F23L, Supplying Air or Non-Combustible Liquids or Gases to Combustion Apparatus in General; Valves or Dampers Specially Adapted for Controlling Air Supply or Draught in Combustion Apparatus; Inducing Draught in Combustion Apparatus; Tops for Chimneys or Ventilating Shafts; Terminals for Flues | Supplying Air or Non-Combustible Liquids or Gases to Combustion Apparatus in General; Valves or Dampers Specially Adapted for Controlling Air Supply or Draught in Combustion Apparatus; Inducing Draught in Combustion Apparatus; Tops for Chimneys or Ventilating Shafts; Terminals for Flues | 24,279 | 8.1% |
| 5 | F23C, Methods or Apparatus for Combustion Using Fluid Fuel or Solid Fuel Suspended in Air | Methods or Apparatus for Combustion Using Fluid Fuel or Solid Fuel Suspended in Air | 19,304 | 6.4% |
| 6 | F23R, Generating Combustion Products of High Pressure or High Velocity, e.g. Gas-Turbine Combustion Chambers | Generating Combustion Products of High Pressure or High Velocity, e.g. Gas-Turbine Combustion Chambers | 17,458 | 5.8% |
| 7 | F23K | Feeding Fuel to Combustion Apparatus | 17,228 | 5.7% |
| 8 | F23N, Regulating or Controlling Combustion | Regulating or Controlling Combustion | 15,400 | 5.1% |
| 9 | F23Q, Ignition; Extinguishing Devices | Ignition; Extinguishing Devices | 12,442 | 4.1% |
| 10 | F23B, Methods or Apparatus for Combustion Using Only Solid Fuel | Methods or Apparatus for Combustion Using Only Solid Fuel | 9,943 | 3.3% |
Source: EPO PATSTAT, worldwide filings
Related Keywords
3 direct subcodes
Child Classifications
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Top Applicants
Top 10 applicants by patent filingsfor class F23, 2013–2023, worldwide · Source: EPO PATSTAT
- GE (GENERAL ELECTRIC COMPANY) US 2,124
- XIAN THERMAL POWER RESEARCH INSTITUTE COMPANY 1,369
- NINGBO FOTILE KITCHENWARE COMPANY 1,363
- SIEMENS DE 997
- UNITED TECHNOLOGIES CORPORATION (UTC) US 937
- GE (GENERAL ELECTRIC COMPANY) 898
- VATTI 815
- CHINESE ACADEMY OF SCIENCES 719
- RINNAI COMPANY 708
- MITSUBISHI HITACHI POWER SYSTEMS 670