F03C
Positive-displacement engines driven by liquids
Official title: POSITIVE-DISPLACEMENT ENGINES DRIVEN BY LIQUIDS (positive- displacement engines for liquids and elastic fluids F01; positive- displacement machines for liquids F04; fluid-pressure actuators F15B; fluid gearing F16H)
F03C (Positive-displacement engines driven by liquids) appears on 991 US grants and 803 published applications in this corpus.
Search patents in F03C- Granted patents
- 991
- Published applications
- 803
- Assignees
- 394
- Inventors
- 1,566
- Latest grant
- 29 Sep 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 37 | 0 |
| 1977 | 29 | 0 |
| 1978 | 27 | 0 |
| 1979 | 7 | 0 |
| 1980 | 18 | 0 |
| 1981 | 8 | 0 |
| 1982 | 8 | 0 |
| 1983 | 11 | 0 |
| 1984 | 10 | 0 |
| 1985 | 12 | 0 |
| 1986 | 9 | 0 |
| 1987 | 10 | 0 |
| 1988 | 12 | 0 |
| 1989 | 4 | 0 |
| 1990 | 4 | 0 |
| 1991 | 9 | 0 |
| 1992 | 8 | 0 |
| 1993 | 13 | 0 |
| 1994 | 3 | 0 |
| 1995 | 9 | 0 |
| 1996 | 9 | 0 |
| 1997 | 14 | 0 |
| 1998 | 18 | 0 |
| 1999 | 13 | 0 |
| 2000 | 13 | 0 |
| 2001 | 15 | 4 |
| 2002 | 19 | 9 |
| 2003 | 11 | 15 |
| 2004 | 13 | 16 |
| 2005 | 11 | 19 |
| 2006 | 10 | 19 |
| 2007 | 14 | 20 |
| 2008 | 8 | 25 |
| 2009 | 9 | 20 |
| 2010 | 11 | 14 |
| 2011 | 8 | 22 |
| 2012 | 23 | 24 |
| 2013 | 24 | 39 |
| 2014 | 24 | 46 |
| 2015 | 29 | 59 |
| 2016 | 34 | 48 |
| 2017 | 43 | 57 |
| 2018 | 37 | 51 |
| 2019 | 60 | 56 |
| 2020 | 59 | 53 |
| 2021 | 51 | 47 |
| 2022 | 37 | 33 |
| 2023 | 48 | 34 |
| 2024 | 28 | 30 |
| 2025 | 32 | 24 |
| 2026 | 18 | 19 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Main groups
Granted patents with any code in the group
Recent patents
- Fluid-pressure rotary actuator for clamping systems29 Sep 2026US 12,746,641 B2Rapid Design Solutions, LLC
- Hydraulic axial piston machine25 Aug 2026US 12,716,356 B2Danfoss A/S
- Axial piston machine with neutral valve integrated in the pot-like housing part11 Aug 2026US 12,704,108 B2Robert Bosch GmbH
- Slipper component with ceramic surface11 Aug 2026US 12,704,117 B2Ocean Pacific Technologies
- Rubber compound reinforced with alternative fibers23 Jun 2026US 12,661,856 B2Abaco Drilling Technologies LLC
- Hydraulic motor8 Oct 2026US 2026/0309121 A1Worldpower AS
- Improved pressure adapter for hydraulic system8 Oct 2026US 2026/0309122 A1Poclain Hydraulics Industrie
- Volumetric variable displacement machine8 Oct 2026US 2026/0309147 A1
- Hydrostatic Rotary Machine Having Pins That Engage Grooves of a Cam Ring24 Sep 2026US 2026/0286928 A1Robert Bosch GmbH
- Improved axial piston hydraulic machine6 Aug 2026US 2026/0226888 A1
Most cited
By later US patents
- Proportioning pump with pneumatic distributor64US 4,047,850 ACommissariat A L' Energie Atomique · 1977
- Tandem hydraulic motor59US 5,207,060 ASauer Inc. · 1993
- Hydraulic engine powered by introduction and removal of heat from a working fluid57US 5,899,067 A1999
- Electrochemical actuator and method of making same51US 5,671,905 A1997
- Adaptive fluid motor control51US 5,794,442 A1998