F04C 29/0021
Systems for the equilibration of forces acting on the pump
Official title: {Systems for the equilibration of forces acting on the pump (interstice adjustment other than by fluid pressure F01C21/102)}
F04C29/0021 (Systems for the equilibration of forces acting on the pump) appears on 555 US grants and 465 published applications in this corpus.
Search patents in F04C- Granted patents
- 555
- Published applications
- 465
- Assignees
- 210
- Inventors
- 1,180
- Latest grant
- 8 Sep 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1979 | 2 | 0 |
| 1980 | 4 | 0 |
| 1981 | 0 | 0 |
| 1982 | 1 | 0 |
| 1983 | 0 | 0 |
| 1984 | 9 | 0 |
| 1985 | 5 | 0 |
| 1986 | 4 | 0 |
| 1987 | 9 | 0 |
| 1988 | 6 | 0 |
| 1989 | 13 | 0 |
| 1990 | 8 | 0 |
| 1991 | 11 | 0 |
| 1992 | 10 | 0 |
| 1993 | 8 | 0 |
| 1994 | 15 | 0 |
| 1995 | 9 | 0 |
| 1996 | 5 | 0 |
| 1997 | 9 | 0 |
| 1998 | 9 | 0 |
| 1999 | 6 | 0 |
| 2000 | 19 | 0 |
| 2001 | 13 | 1 |
| 2002 | 9 | 9 |
| 2003 | 9 | 10 |
| 2004 | 10 | 8 |
| 2005 | 8 | 14 |
| 2006 | 7 | 19 |
| 2007 | 7 | 11 |
| 2008 | 7 | 10 |
| 2009 | 7 | 11 |
| 2010 | 1 | 16 |
| 2011 | 11 | 14 |
| 2012 | 7 | 15 |
| 2013 | 15 | 8 |
| 2014 | 7 | 16 |
| 2015 | 21 | 30 |
| 2016 | 12 | 15 |
| 2017 | 20 | 26 |
| 2018 | 16 | 27 |
| 2019 | 22 | 22 |
| 2020 | 24 | 38 |
| 2021 | 32 | 26 |
| 2022 | 29 | 23 |
| 2023 | 19 | 24 |
| 2024 | 36 | 24 |
| 2025 | 32 | 25 |
| 2026 | 12 | 23 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Vortex compressor8 Sep 2026US 12,729,684 B2Robert Bosch GmbH
- Scroll compressors including ring-shaped counterweight assemblies1 Sep 2026US 12,723,587 B2Copeland Corporation
- Scroll compressor including back pressure communication unit2 Jun 2026US 12,644,454 B2LG Electronics Inc.
- Co-rotating scroll compressor2 Jun 2026US 12,644,455 B2Kabushiki Kaisha Toyota Jidoshokki
- Positive displacement roots blower noise suppression12 May 2026US 12,624,693 B2Ingersoll-Rand Industrial U.S., Inc.
- Scroll compressor30 Jul 2026US 2026/0218704 A1
- Air Compressor30 Jul 2026US 2026/0218705 A1Hitachi Industrial Equipment Systems Co., Ltd.
- Scroll compressor16 Jul 2026US 2026/0201882 A1Hanon Systems
- Scroll compressor16 Jul 2026US 2026/0201884 A1Kabushiki Kaisha Toyota Jidoshokki
- Electric compressor2 Jul 2026US 2026/0185525 A1
Most cited
By later US patents
- Portable ventilator system278US 7,188,621 B2Pulmonetic Systems, Inc. · 2007
- Scroll compressor with a thrust reduction mechanism96US 4,696,630 AKabushiki Kaisha Toshiba · 1987
- Scroll compressor with valved port for each compression chamber91US 4,818,195 AHitachi, Ltd. · 1989
- Mechanical ventilation system utilizing bias valve85US 8,118,024 B2CareFusion 203, Inc. · 2012
- Compressor having refrigerant injection ports70US 5,722,257 ADenso Corporation · 1998