F27B
Furnaces, kilns, ovens or retorts in general
Official title: Furnaces, kilns, ovens or retorts in general; open sintering or like apparatus
F27B (Furnaces, kilns, ovens or retorts in general) appears on 7,450 US grants and 5,549 published applications in this corpus.
Search patents in F27B- Granted patents
- 7,450
- Published applications
- 5,549
- Assignees
- 3,395
- Inventors
- 14,633
- Latest grant
- 6 Oct 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 133 | 0 |
| 1977 | 136 | 0 |
| 1978 | 113 | 0 |
| 1979 | 81 | 0 |
| 1980 | 139 | 0 |
| 1981 | 157 | 0 |
| 1982 | 142 | 0 |
| 1983 | 153 | 0 |
| 1984 | 169 | 0 |
| 1985 | 170 | 0 |
| 1986 | 141 | 0 |
| 1987 | 125 | 0 |
| 1988 | 129 | 0 |
| 1989 | 144 | 0 |
| 1990 | 131 | 0 |
| 1991 | 133 | 0 |
| 1992 | 120 | 0 |
| 1993 | 132 | 0 |
| 1994 | 143 | 0 |
| 1995 | 127 | 0 |
| 1996 | 119 | 0 |
| 1997 | 106 | 0 |
| 1998 | 163 | 0 |
| 1999 | 178 | 0 |
| 2000 | 143 | 0 |
| 2001 | 148 | 47 |
| 2002 | 142 | 99 |
| 2003 | 131 | 118 |
| 2004 | 130 | 169 |
| 2005 | 82 | 125 |
| 2006 | 89 | 158 |
| 2007 | 66 | 165 |
| 2008 | 92 | 220 |
| 2009 | 93 | 194 |
| 2010 | 132 | 221 |
| 2011 | 137 | 229 |
| 2012 | 164 | 281 |
| 2013 | 169 | 274 |
| 2014 | 175 | 258 |
| 2015 | 194 | 289 |
| 2016 | 205 | 291 |
| 2017 | 240 | 209 |
| 2018 | 196 | 237 |
| 2019 | 205 | 202 |
| 2020 | 198 | 219 |
| 2021 | 159 | 246 |
| 2022 | 162 | 246 |
| 2023 | 192 | 280 |
| 2024 | 194 | 284 |
| 2025 | 199 | 278 |
| 2026 | 129 | 210 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Main groups
Granted patents with any code in the group
- F27B 9/00Furnaces through which the charge is moved mechanically1,745
- F27B 3/00Hearth-type furnaces1,404
- F27B 17/00Furnaces of a kind not covered by any of groups f27b1/00 -1,215
- F27B 7/00Rotary-drum furnaces, i.e. horizontal or slightly inclined1,187
- F27B 14/00Crucible or pot furnaces712
- F27B 1/00Shaft or like vertical or substantially vertical furnaces704
- F27B 5/00Muffle furnaces526
- F27B 15/00Fluidised-bed furnaces407
Recent patents
- Object orientation adjusting device6 Oct 2026US 12,753,020 B2NGK Insulators, Ltd.
- Method for manufacturing direct reduced iron and DRI manufacturing equipment6 Oct 2026US 12,753,452 B2ArcelorMittal
- Induction coils as non-contact temperature boosters and flow boosters for ferrous and non-ferrous materials in a furnace6 Oct 2026US 12,753,973 B2Inductotherm Corp.
- Dental furnace and method for operating a dental furnace29 Sep 2026US 12,747,914 B2Vita Zahnfabrik H. Rauter GmbH & Co.KG
- Heat treatment system22 Sep 2026US 12,742,596 B2NGK Insulators, Ltd.
- Sintering devices, sintering assemblies, and associated methods8 Oct 2026US 2026/0307146 A1Battelle Energy Alliance, LLC
- Multiple hearth furnace for placing a solid and a gas in contact8 Oct 2026US 2026/0309411 A1Avril
- Parallel-flow regenerative shaft kiln and method for burning carbonate rock8 Oct 2026US 2026/0309418 A1Maerz Ofenbau AG
- Climate-friendly puzzolana production8 Oct 2026US 2026/0309419 A1thyssenkrupp AG
- Direct-fired kiln using recycled flue gas8 Oct 2026US 2026/0309420 A1ExxonMobil Technology and Engineering Company
Most cited
By later US patents
- Movable core fast cool-down furnace577US 4,753,192 ABTU Engineering Corporation · 1988
- Thermal process station with heated lid553US 6,884,066 B2FSI International, Inc. · 2005
- Susceptor heater shim529US 9,202,727 B2ASM IP Holding B. V. · 2015
- Temperature control system for a thermal reactor499US 6,441,350 B1Brooks Automation, Inc. · 2002
- Substrate heat treatment apparatus491US 7,432,476 B2Dainippon Screen Mfg.Co., Ltd. · 2008