F02B 23/08
Internal-combustion piston engines: other engines characterised by special shape or construction of
Official title: with positive ignition
F02B23/08 (Internal-combustion piston engines: other engines characterised by special shape or construction of) appears on 1,429 US grants and 1,039 published applications in this corpus.
Search patents in F02B- Granted patents
- 1,429
- Published applications
- 1,039
- Assignees
- 332
- Inventors
- 2,275
- Latest grant
- 12 May 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 4 | 0 |
| 1977 | 5 | 0 |
| 1978 | 14 | 0 |
| 1979 | 7 | 0 |
| 1980 | 10 | 0 |
| 1981 | 13 | 0 |
| 1982 | 16 | 0 |
| 1983 | 8 | 0 |
| 1984 | 12 | 0 |
| 1985 | 18 | 0 |
| 1986 | 5 | 0 |
| 1987 | 14 | 0 |
| 1988 | 25 | 0 |
| 1989 | 8 | 0 |
| 1990 | 16 | 0 |
| 1991 | 11 | 0 |
| 1992 | 15 | 0 |
| 1993 | 23 | 0 |
| 1994 | 17 | 0 |
| 1995 | 10 | 0 |
| 1996 | 12 | 0 |
| 1997 | 18 | 0 |
| 1998 | 40 | 0 |
| 1999 | 50 | 0 |
| 2000 | 62 | 0 |
| 2001 | 52 | 18 |
| 2002 | 59 | 67 |
| 2003 | 71 | 50 |
| 2004 | 54 | 59 |
| 2005 | 52 | 45 |
| 2006 | 46 | 53 |
| 2007 | 43 | 54 |
| 2008 | 53 | 50 |
| 2009 | 24 | 67 |
| 2010 | 48 | 35 |
| 2011 | 30 | 32 |
| 2012 | 31 | 35 |
| 2013 | 33 | 30 |
| 2014 | 23 | 42 |
| 2015 | 30 | 49 |
| 2016 | 35 | 53 |
| 2017 | 44 | 42 |
| 2018 | 42 | 39 |
| 2019 | 39 | 57 |
| 2020 | 55 | 46 |
| 2021 | 46 | 38 |
| 2022 | 35 | 17 |
| 2023 | 19 | 20 |
| 2024 | 19 | 18 |
| 2025 | 9 | 15 |
| 2026 | 4 | 8 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Stratified nitrogen enriched air (NEA) strategies and methods to reduce NOx emissions from engines12 May 2026US 12,624,654 B2Saudi Arabian Oil Company
- Spray guided stratification for fueling a passive pre-chamber3 Mar 2026US 12,565,849 B2Saudi Arabian Oil Company
- Engine having hotspot fuel igniter and piston and methodology using same3 Mar 2026US 12,565,865 B2Caterpillar Inc.
- Internal combustion engine system10 Feb 2026US 12,546,263 B2Volvo Truck Corporation
- Internal combustion engine system30 Dec 2025US 12,510,035 B2Volvo Truck Corporation
- Engine13 Aug 2026US 2026/0235068 A1Ishikawa Energy Research Co., Ltd.
- Engine and operating strategy augmenting tumble flow to increase fuel-air mixing30 Jul 2026US 2026/0218671 A1Caterpillar Inc.
- Wall-guided spark assistance for cold operations in gasoline compression ignition engines16 Jul 2026US 2026/0201828 A1Aramco Services Company
- Gaseous fuel combustion system and method utilizing a piston reentrant feature for hastened fuel-air mixing16 Jul 2026US 2026/0201829 A1Caterpillar Inc.
- Gaseous fuel engine system and method utilizing scalloped piston for hastened fuel-air mixing2 Jul 2026US 2026/0185496 A1Caterpillar Inc.
Most cited
By later US patents
- System and method for engine starting160US 7,159,568 B1Ford Global Technologies, LLC · 2007
- Optimized fuel management system for direct injection ethanol enhancement of gasoline engines129US 7,225,787 B2Massachusetts Institute of Technology · 2007
- Plasma jet ignition engine and method122US 4,203,393 AFord Motor Company · 1980
- Compression autoignition gasoline engine114US 6,336,436 B12002
- In-cylinder direct-injection spark-ignition engine98US 6,138,639 ANissan Motor Co., Ltd. · 2000