F04B 39/0011
Liquid pistons
Official title: {liquid pistons}
F04B39/0011 (Liquid pistons) appears on 45 US grants and 54 published applications in this corpus.
Search patents in F04B- Granted patents
- 45
- Published applications
- 54
- Assignees
- 43
- Inventors
- 108
- Latest grant
- 21 Jul 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 1 | 0 |
| 1977 | 2 | 0 |
| 1978 | 1 | 0 |
| 1979 | 0 | 0 |
| 1980 | 1 | 0 |
| 1981 | 0 | 0 |
| 1982 | 1 | 0 |
| 1983 | 0 | 0 |
| 1984 | 0 | 0 |
| 1985 | 0 | 0 |
| 1986 | 0 | 0 |
| 1987 | 0 | 0 |
| 1988 | 1 | 0 |
| 1989 | 0 | 0 |
| 1990 | 0 | 0 |
| 1991 | 1 | 0 |
| 1992 | 1 | 0 |
| 1993 | 0 | 0 |
| 1994 | 0 | 0 |
| 1995 | 0 | 0 |
| 1996 | 0 | 0 |
| 1997 | 0 | 0 |
| 1998 | 2 | 0 |
| 1999 | 0 | 0 |
| 2000 | 0 | 0 |
| 2001 | 1 | 0 |
| 2002 | 0 | 0 |
| 2003 | 0 | 0 |
| 2004 | 0 | 0 |
| 2005 | 0 | 1 |
| 2006 | 0 | 1 |
| 2007 | 0 | 0 |
| 2008 | 0 | 2 |
| 2009 | 1 | 0 |
| 2010 | 1 | 1 |
| 2011 | 1 | 1 |
| 2012 | 0 | 2 |
| 2013 | 0 | 4 |
| 2014 | 0 | 2 |
| 2015 | 3 | 2 |
| 2016 | 3 | 5 |
| 2017 | 1 | 3 |
| 2018 | 3 | 3 |
| 2019 | 1 | 4 |
| 2020 | 5 | 1 |
| 2021 | 2 | 6 |
| 2022 | 0 | 3 |
| 2023 | 4 | 2 |
| 2024 | 2 | 3 |
| 2025 | 1 | 5 |
| 2026 | 5 | 3 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Compression of hydrogen gas with vapor control21 Jul 2026US 12,687,158 B1
- Compression of indifferent gases with vapor control21 Jul 2026US 12,687,159 B1
- Magnetic fluid micropump21 Apr 2026US 12,607,176 B2Qinghai Institute of Technology
- Method and apparatus to compress hydrogen gas with vapor control24 Mar 2026US 12,584,471 B1
- Mechanical liquid piston slow expansion compressor13 Jan 2026US 12,523,210 B2
- Hydrogen store having a liquid piston10 Sep 2026US 2026/0266279 A1Maximator GmbH
- Near-isothermal gas compressor and/or /expander system30 Jul 2026US 2026/0218693 A1University of Virginia Patent Foundation
- Device for energy conversion7 May 2026US 2026/0125993 A1Segula Engineering
- Magnetic fluid micropump25 Dec 2025US 2025/0389262 A1Qinghai Institute of Technology
- Pistonless apparatus and system for gas compression and the method for compression of a gas18 Dec 2025US 2025/0382977 A1Gas Technologies LLC
Most cited
By later US patents
- Gas compressor95US 5,771,693 ANational Power PLC · 1998
- Fluid piston compressor17US 5,073,090 A1991
- Hermetic refrigeration compressor16US 5,733,108 AWhite Consolidated Industries, Inc. · 1998
- Refrigerant gas compressor construction15US 5,106,278 ABristol Compressors, Inc. · 1992
- Apparatus for compressing a gas14US 4,750,409 A1988