F15B 2211/61
Secondary circuits
F15B2211/61 (Secondary circuits) appears on 333 US grants and 350 published applications in this corpus.
Search patents in F15B- Granted patents
- 333
- Published applications
- 350
- Assignees
- 176
- Inventors
- 688
- Latest grant
- 6 Oct 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 3 | 0 |
| 1977 | 5 | 0 |
| 1978 | 1 | 0 |
| 1979 | 1 | 0 |
| 1980 | 2 | 0 |
| 1981 | 0 | 0 |
| 1982 | 4 | 0 |
| 1983 | 0 | 0 |
| 1984 | 0 | 0 |
| 1985 | 1 | 0 |
| 1986 | 0 | 0 |
| 1987 | 0 | 0 |
| 1988 | 1 | 0 |
| 1989 | 2 | 0 |
| 1990 | 1 | 0 |
| 1991 | 4 | 0 |
| 1992 | 1 | 0 |
| 1993 | 0 | 0 |
| 1994 | 1 | 0 |
| 1995 | 2 | 0 |
| 1996 | 2 | 0 |
| 1997 | 2 | 0 |
| 1998 | 3 | 0 |
| 1999 | 1 | 0 |
| 2000 | 6 | 0 |
| 2001 | 3 | 0 |
| 2002 | 3 | 3 |
| 2003 | 3 | 7 |
| 2004 | 6 | 5 |
| 2005 | 5 | 6 |
| 2006 | 4 | 9 |
| 2007 | 8 | 7 |
| 2008 | 6 | 9 |
| 2009 | 7 | 14 |
| 2010 | 9 | 6 |
| 2011 | 6 | 5 |
| 2012 | 2 | 10 |
| 2013 | 7 | 29 |
| 2014 | 21 | 28 |
| 2015 | 16 | 26 |
| 2016 | 10 | 20 |
| 2017 | 24 | 20 |
| 2018 | 20 | 17 |
| 2019 | 21 | 17 |
| 2020 | 22 | 15 |
| 2021 | 22 | 13 |
| 2022 | 10 | 31 |
| 2023 | 17 | 13 |
| 2024 | 15 | 8 |
| 2025 | 11 | 20 |
| 2026 | 12 | 12 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Control method based on a four-chamber hydraulic cylinder6 Oct 2026US 12,753,780 B2Taiyuan University of Technology
- Hydraulic system with cooling circuit and machine tool8 Sep 2026US 12,729,701 B2HAWE Hydraulik SE
- Temperature regulation system for vehicle hydraulic system25 Aug 2026US 12,716,434 B2Oshkosh Corporation
- Hydraulic machine swing system with anti-drift9 Jun 2026US 12,650,003 B2Caterpillar Inc.
- Energy storage and reutilization for a single-rod electro-hydrostatic actuator9 Jun 2026US 12,650,138 B2University of Manitoba
- Fluid pressure circuit3 Sep 2026US 2026/0258821 A1Eagle Industry Co., Ltd.
- Transport vehicle20 Aug 2026US 2026/0241846 A1Hitachi Construction Machinery Co., Ltd.
- Mobile machine with improved electric powered actuator system6 Aug 2026US 2026/0226710 A1Moog Inc.
- Integrated Electrohydraulic Actuator30 Jul 2026US 2026/0218734 A1Parker-Hannifin Corporation
- Construction machine9 Jul 2026US 2026/0193869 A1Hitachi Construction Machinery Co., Ltd.
Most cited
By later US patents
- Shovel64US 6,789,335 B1Kobelco Construction Machinery Co., Ltd. · 2004
- Hydraulic drive and steering systems for a vehicle48US 5,427,195 AInt. Silvatech Ltd. · 1995
- Device for cooling components by means of hydraulic fluid from a hydraulic circuit43US 6,672,056 B2Linde Aktiengesellschaft · 2004
- Apparatus for recovering pressure oil returned from actuators39US 6,151,894 AKomatsu Ltd. · 2000
- Safety device for hydraulic closed circuit38US 5,048,294 AHitachi Construction Machinery Co., Ltd. · 1991