F01B 7/00
Machines or engines with two or more pistons reciprocating within same cylinder
Official title: Machines or engines with two or more pistons reciprocating within same cylinder or within essentially coaxial cylinders (in opposite arrangement relative to main shaft F01B1/08)
F01B7/00 (Machines or engines with two or more pistons reciprocating within same cylinder) appears on 417 US grants and 348 published applications in this corpus.
Search patents in F01B- Granted patents
- 417
- Published applications
- 348
- Assignees
- 111
- Inventors
- 435
- Latest grant
- 30 Dec 2025
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 3 | 0 |
| 1977 | 7 | 0 |
| 1978 | 4 | 0 |
| 1979 | 6 | 0 |
| 1980 | 5 | 0 |
| 1981 | 7 | 0 |
| 1982 | 7 | 0 |
| 1983 | 4 | 0 |
| 1984 | 5 | 0 |
| 1985 | 5 | 0 |
| 1986 | 2 | 0 |
| 1987 | 4 | 0 |
| 1988 | 1 | 0 |
| 1989 | 11 | 0 |
| 1990 | 3 | 0 |
| 1991 | 6 | 0 |
| 1992 | 3 | 0 |
| 1993 | 5 | 0 |
| 1994 | 6 | 0 |
| 1995 | 3 | 0 |
| 1996 | 1 | 0 |
| 1997 | 2 | 0 |
| 1998 | 5 | 0 |
| 1999 | 1 | 0 |
| 2000 | 3 | 0 |
| 2001 | 5 | 0 |
| 2002 | 0 | 0 |
| 2003 | 1 | 0 |
| 2004 | 0 | 4 |
| 2005 | 1 | 2 |
| 2006 | 1 | 4 |
| 2007 | 8 | 4 |
| 2008 | 4 | 6 |
| 2009 | 3 | 9 |
| 2010 | 3 | 13 |
| 2011 | 3 | 9 |
| 2012 | 4 | 24 |
| 2013 | 16 | 24 |
| 2014 | 26 | 24 |
| 2015 | 17 | 18 |
| 2016 | 20 | 31 |
| 2017 | 28 | 38 |
| 2018 | 32 | 20 |
| 2019 | 25 | 31 |
| 2020 | 27 | 31 |
| 2021 | 31 | 18 |
| 2022 | 21 | 11 |
| 2023 | 12 | 10 |
| 2024 | 11 | 9 |
| 2025 | 9 | 3 |
| 2026 | 0 | 5 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
- F01B 7/02Machines or engines with two or more pistons reciprocating within same cylinder318
- F01B 7/20Machines or engines with two or more pistons reciprocating within same cylinder43
- F01B 7/16Machines or engines with two or more pistons reciprocating within same cylinder29
- F01B 7/18Machines or engines with two or more pistons reciprocating within same cylinder16
Recent patents
- Piston bearing assembly for an opposed-piston engine30 Dec 2025US 12,510,015 B2General Atomics Aeronautical Systems, Inc.
- Opposed-piston internal combustion engine25 Nov 2025US 12,480,439 B2Umu Devising LLC
- Piston with a biaxial bearing for an opposed-piston engine14 Oct 2025US 12,442,328 B2Achates Power, Inc.
- High-efficiency linear generator23 Sep 2025US 12,421,890 B2Mainspring Energy, Inc.
- Opposed-piston internal combustion engine16 Sep 2025US 12,416,257 B2
- Engine13 Aug 2026US 2026/0235068 A1Ishikawa Energy Research Co., Ltd.
- Piston in piston variable displacement hydraulic device30 Jul 2026US 2026/0218690 A1
- Opposed-piston engine26 Mar 2026US 2026/0085630 A1Kubota Corporation
- Internal combustion engine12 Feb 2026US 2026/0043373 A1
- Internal combustion engine12 Feb 2026US 2026/0043374 A1
Most cited
By later US patents
- Internal combustion engine with compound air compression138US 5,362,219 A1994
- Internal combustion engine83US 6,279,550 B12001
- Opposed-piston, opposed-cylinder engine with collinear cylinders71US 8,763,583 B2EcoMotors, Inc. · 2014
- Cold air super-charged internal combustion engine, working cycle and method69US 6,951,211 B22005
- Variable-cycle reciprocating internal combustion engine64US 4,856,463 A1989