F02G 1/0435
The engine being of the free piston type
Official title: {the engine being of the free piston type}
F02G1/0435 (The engine being of the free piston type) appears on 395 US grants and 178 published applications in this corpus.
Search patents in F02G- Granted patents
- 395
- Published applications
- 178
- Assignees
- 135
- Inventors
- 452
- Latest grant
- 24 Mar 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 7 | 0 |
| 1977 | 9 | 0 |
| 1978 | 4 | 0 |
| 1979 | 5 | 0 |
| 1980 | 5 | 0 |
| 1981 | 7 | 0 |
| 1982 | 13 | 0 |
| 1983 | 24 | 0 |
| 1984 | 19 | 0 |
| 1985 | 8 | 0 |
| 1986 | 5 | 0 |
| 1987 | 11 | 0 |
| 1988 | 10 | 0 |
| 1989 | 14 | 0 |
| 1990 | 11 | 0 |
| 1991 | 8 | 0 |
| 1992 | 19 | 0 |
| 1993 | 6 | 0 |
| 1994 | 5 | 0 |
| 1995 | 8 | 0 |
| 1996 | 5 | 0 |
| 1997 | 4 | 0 |
| 1998 | 4 | 0 |
| 1999 | 5 | 0 |
| 2000 | 5 | 0 |
| 2001 | 13 | 1 |
| 2002 | 8 | 4 |
| 2003 | 8 | 10 |
| 2004 | 7 | 12 |
| 2005 | 11 | 10 |
| 2006 | 8 | 2 |
| 2007 | 6 | 5 |
| 2008 | 2 | 12 |
| 2009 | 5 | 7 |
| 2010 | 10 | 9 |
| 2011 | 1 | 10 |
| 2012 | 4 | 3 |
| 2013 | 5 | 8 |
| 2014 | 10 | 6 |
| 2015 | 4 | 5 |
| 2016 | 7 | 9 |
| 2017 | 6 | 1 |
| 2018 | 7 | 12 |
| 2019 | 3 | 7 |
| 2020 | 9 | 14 |
| 2021 | 11 | 4 |
| 2022 | 9 | 10 |
| 2023 | 5 | 7 |
| 2024 | 8 | 5 |
| 2025 | 5 | 3 |
| 2026 | 2 | 2 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Single cylinder internally heated stirling engine24 Mar 2026US 12,584,454 B2
- Thermo-magnetic motor10 Mar 2026US 12,571,357 B1
- Asymmetric gas bearing bushing for thermo-pump21 Oct 2025US 12,448,963 B2KLA Corporation
- Stirling engine with at least four piston assemblies7 Oct 2025US 12,435,681 B2Regensys Ltd
- Free-piston Stirling engine7 Oct 2025US 12,435,911 B2Twinbird Corporation
- Stirling cycle heat pump with actuated regenerator and integrated displacer23 Apr 2026US 2026/0110277 A1Raytheon Company
- Hot-gas free-piston stirling engine with efficient hot air inlet2 Apr 2026US 2026/0092576 A1Exowatt, Inc.
- Single cylinder internally heated stirling engine4 Sep 2025US 2025/0277474 A1
- Stirling cycle machine27 Feb 2025US 2025/0067230 A1DEKA Products Limited Partnership
- Stirling cycle machine23 Jan 2025US 2025/0027461 A1DEKA Products Limited Partnership
Most cited
By later US patents
- Hybrid electric propulsion system164US 5,172,784 A1992
- Pressure swing adsorption for concentration of a gas component102US 4,968,329 A1990
- Apparatus and process for pressure swing adsorption separation100US 4,801,308 A1989
- Fluid bearing with compliant linkage for centering reciprocating bodies84US 5,525,845 ASunPower Corporation · 1996
- Double acting thermodynamically resonant free-piston multicylinder stirling system and method78US 7,134,279 B2Infinia Corporation · 2006