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CPC Subgroup
F23R 3/42

characterised by the arrangement or form of the flame tubes or combustion chambers

Full Title

Continuous combustion chambers using liquid or gaseous fuel > characterised by the arrangement or form of the flame tubes or combustion chambers

Filing statistics

CPC F23R 3/42 belongs to the parent subclass F23R, which recorded 18,438 patent applications worldwide between 2013 and 2023. Annual filings declined from 2,081 in 2013 to 1,384 in 2023 (-33%), peaking at 2,105 applications in 2014. The most active applicants in class F23 are GE (GENERAL ELECTRIC COMPANY) (2,581 applications), UNITED TECHNOLOGIES CORPORATION (UTC) (1,180 applications) and SIEMENS (1,157 applications).

Source: EPO PATSTAT, worldwide filings

9 direct subcodes

Child Classifications

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  • F23R 3/44 Combustion chambers comprising a tubular flame tube within a tubular casing (reverse-flow combustion chambers F23R3/54)
  • F23R 3/50 Combustion chambers comprising an annular flame tube within an annular casing (toroidal combustion chambers F23R3/52)
  • F23R 3/52 Toroidal combustion chambers
  • F23R 3/54 Reverse-flow combustion chambers
  • F23R 3/56 Combustion chambers having rotary flame tubes
  • F23R 3/58 Cyclone or vortex type combustion chambers
  • F23R 3/60 Support structures; Attaching or mounting means

Top Applicants

Top 10 applicants by patent filingsfor class F23, 2013–2023, worldwide · Source: EPO PATSTAT

  1. GE (GENERAL ELECTRIC COMPANY) US 2,581
  2. UNITED TECHNOLOGIES CORPORATION (UTC) US 1,180
  3. SIEMENS DE 1,157
  4. GE (GENERAL ELECTRIC COMPANY) 994
  5. XIAN THERMAL POWER RESEARCH INSTITUTE COMPANY 769
  6. MITSUBISHI HEAVY INDUSTRIES JP 701
  7. MITSUBISHI HITACHI POWER SYSTEMS JP 695
  8. RAYTHEON TECHNOLOGIES CORPORATION US 587
  9. NINGBO FOTILE KITCHENWARE COMPANY 543
  10. GENERAL ELECTRIC TECHNOLOGY CH 490