F04B 1/2021
Characterised by the contact area between cylinder barrel and valve plate
Official title: characterised by the contact area between cylinder barrel and valve plate
F04B1/2021 (Characterised by the contact area between cylinder barrel and valve plate) appears on 116 US grants and 99 published applications in this corpus.
Search patents in F04B- Granted patents
- 116
- Published applications
- 99
- Assignees
- 69
- Inventors
- 258
- Latest grant
- 25 Aug 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 1 | 0 |
| 1977 | 1 | 0 |
| 1978 | 0 | 0 |
| 1979 | 1 | 0 |
| 1980 | 0 | 0 |
| 1981 | 0 | 0 |
| 1982 | 0 | 0 |
| 1983 | 0 | 0 |
| 1984 | 2 | 0 |
| 1985 | 1 | 0 |
| 1986 | 0 | 0 |
| 1987 | 0 | 0 |
| 1988 | 3 | 0 |
| 1989 | 0 | 0 |
| 1990 | 2 | 0 |
| 1991 | 0 | 0 |
| 1992 | 3 | 0 |
| 1993 | 2 | 0 |
| 1994 | 0 | 0 |
| 1995 | 0 | 0 |
| 1996 | 4 | 0 |
| 1997 | 4 | 0 |
| 1998 | 3 | 0 |
| 1999 | 1 | 0 |
| 2000 | 1 | 0 |
| 2001 | 0 | 0 |
| 2002 | 4 | 3 |
| 2003 | 2 | 1 |
| 2004 | 0 | 4 |
| 2005 | 5 | 2 |
| 2006 | 1 | 2 |
| 2007 | 0 | 4 |
| 2008 | 2 | 4 |
| 2009 | 1 | 4 |
| 2010 | 3 | 2 |
| 2011 | 1 | 2 |
| 2012 | 3 | 1 |
| 2013 | 1 | 3 |
| 2014 | 2 | 5 |
| 2015 | 3 | 5 |
| 2016 | 3 | 8 |
| 2017 | 3 | 5 |
| 2018 | 6 | 2 |
| 2019 | 9 | 5 |
| 2020 | 5 | 3 |
| 2021 | 6 | 6 |
| 2022 | 1 | 6 |
| 2023 | 6 | 7 |
| 2024 | 7 | 5 |
| 2025 | 6 | 6 |
| 2026 | 7 | 4 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Hydraulic axial piston machine25 Aug 2026US 12,716,356 B2Danfoss A/S
- Axial piston pumps25 Aug 2026US 12,716,404 B2Zhong Moyuan Technology (Shanghai) Co., Ltd.
- Slipper component with ceramic surface11 Aug 2026US 12,704,117 B2Ocean Pacific Technologies
- Inline piston pump11 Aug 2026US 12,704,118 B2Eaton Intelligent Power Limited
- Integrated electro-hydraulic unit14 Apr 2026US 12,601,332 B2Robert Bosch GmbH
- Slipper component with ceramic surface30 Jul 2026US 2026/0218689 A1Ocean Pacific Technologies
- Axial piston device12 Mar 2026US 2026/0071606 A1Kubota Corporation
- Axial piston pumps12 Mar 2026US 2026/0071620 A1Zhong Moyuan Technology (Shanghai) Co., Ltd.
- Control plate for a hydraulic machine29 Jan 2026US 2026/0028970 A1
- Piston assembly for hydraulic pump13 Nov 2025US 2025/0347276 A1Goodrich Actuation Systems Limited
Most cited
By later US patents
- Hydraulic pump of the axial piston type43US 4,007,663 AMitsubishi Kogyo Kabushiki Kaisha · 1977
- Cylinder block positive hold-down for cold start-up32US 5,247,794 ASundstrand Corporation · 1993
- Hydraulic transmission device21US 4,771,676 AToshiba Kikai Kabushiki Kaisha · 1988
- Swash plate type axial piston pump21US 5,809,863 AMitsubishi Denki Kabushiki Kaisha · 1998
- Hydraulic motor or pump with constant clamping force between rotor and port plate18US 4,934,251 AAllied-Signal Inc. · 1990